Rivista Della ASSOCIAZIONE GEORISORSE E AMBIENTE 152 Editoriale

ISSN 1121-9041

152

SICUREZZA ED EFFICIENZA NEL MONDO DELLE GALLERIE.

Sicurezza e performance sono le priorità di BASF per il mondo delle costruzioni in sotterraneo. Questo richiede un supporto ingegneristico specializzato, l’applicazione del know-how e una chimica di ultima generazione. BASF può soddisfare le vostre esigenze con la linea Master Builders Solutions. Che stiate cercando un supporto per il consolidamento di un terreno, per rendere più efficiente la vostra TBM o una soluzione a problemi di impermeabilizzazione, la nostra esperienza di leader globale nel calcestruzzo proiettato, nelle tecnologie per l’iniezione e per lo scavo meccanizzato e nelle tecnologie delle membrane a spruzzo vi assisterà nel processo di realizzazione della vostra opera in sotterraneo in modo sicuro e attraverso un’ottimizzazione tecnico-economica. - settembre-dicembre 2017

Per maggiori informazioni visita il sito www.ugc.basf.com GEAM 152 v. in Legge 27/02/2004 n. 46 Art. 1, Comma 1) - CN/BO in Legge 27/02/2004 n. 46 Art. 1, Comma 1) - CN/BO GEAM - Anno LIV n. 3 settembre-dicembre 2017 Quadrimestrale Poste Italiane S.p.A. Sped. in Abb. Postale DL 353/2003 (con v. Pàtron Editore s.r.l. - Via Badini, 12 - Quarto Inferiore 40057 Granarolo dell’Emilia (Bo) - Via Pàtron Editore s.r.l. Pàtron Editore BASF Construction Chemicals Italia Spa - Via Vicinale delle Corti, 21 - I - 31100 Treviso (TV) - T +39 0422 304251 - F +39 0422 429485 - [email protected] - www.basf-cc.it Rivista della ASSOCIAZIONE GEORISORSE E AMBIENTE 152 Editoriale

Italy’s long entrepreneurial history, its technological and scientific excellence along with its pioneering nature in the exploration and development of the petroleum sector have always been at the forefront of research and operations on land and even more at sea; an activity in which innovation plays a fundamental role in guaranteeing the highest safety standards. The 60-year-old commitment that has driven the Italian industry, academia and research institutions to playing a leading role in the sector has not dwindled. On the contrary, credit goes to the Directorate General for Safety of Mining and Energy Activities – National Mining Office for Hydrocarbons and Georesources (DGS UNMIG) to have built on this long tradition and to have stepped up its efforts to coordinate research and technological development towards the new energy policies of the country in fulfillment of the strategic objectives identified in the document on National Energy Strategy (SEN). Along this line, Legislative Decree 145/2015 which implements European Directive 2013/13 / EU on safety issues has been seen by the DGS UNMIG as yet another opportunity to jointly value the knowledge and expertise of the Armed Forces, Research Institutions and Universities. This motivated the creation of the “Network for Offshore Safety”, which was framed as a highly specialized and dynamic scientific reality that develops application results to improve the safety of mining and energy activities at sea, managed and monitored by DGS UNMIG. This special issue dedicated to the “Network for Offshore Safety” published on the Geoengineering Environment and Mining (GEAM) Journal under the patronage and with the contribution of DGS UNMIG, is one of the many actions undertaken by DGS UNMIG for the dissemination of the activities and research results of all the Network’s partners. On that note, it seemed appropriate to gather the individual research under the strategic vision of DGS UNMIG; to this end, the common thread of the Network is emphasized by the issue index which aims at taking the reader through every single contribution without losing focus on the common goal of offshore safety. Last but not least, given its rich and highly qualified national organization nature in line with current European models of research management and by tackling issues of great economic, social and environmental interest, the Network attempts to clarify misinformation through technical-scientific knowledge and by doing so it hopes to encourage constructive discussions on many of the controversies surrounding the topic of safety related to hydrocarbon production offshore. Francesca Verga Paolo Dabove

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 1 Direzione e redazione Associazione Georisorse e Ambiente c/o DIATI – Dip. Ingegneria dell’Ambiente, del Territorio, SOMMARIO e delle Infrastrutture - Politecnico di Torino, Corso Duca degli Abruzzi, 24 – 10129 Torino Tel.: 011 0907681 – Fax: 011 0907689 GEAM – Geoingegneria Ambientale e Mineraria e-mail: [email protected] – www.geam.org Editor in chief Rivista dell’Associazione Georisorse e Ambiente Daniele Peila Anno LIV, n. 3, dicembre 2017 (152) Editors Daniele Martinelli e Paolo Dabove Comitato di Redazione Gian Andrea Blengini - Politecnico di Torino; C. Di Simone, A. Di GreGorio, Marta Bottero - Politecnico di Torino; Claudia 7 51 G. AGATe, r. GuAnDAlini, F. moiA Chiappino - SET s.r.l., Torino; Paolo Dabove F. TerlizzeSe - Politecnico di Torino; Marina De Maio - Po- litecnico di Torino; Cristina Gabriela Oñate Dialogue and transparency for Numerical approach to simulate Salazar - Politecnico di Torino; Carmine Toda- maximum safety: preliminary the sea oil dispersion related to ro - Politecnico di Torino; Laura Turconi - CNR analysis of communication a hypothetical accident - IRPI di Torino. strategy by DGS UNMIG Gestione editoriale affidata a: Pàtron Editore – Via Badini, 12 – 40057 Quarto 58 A. CArPiGnAno, T. CorTi, Inferiore – Granarolo dell’Emilia – Bologna P. Dei, A. FAlCone, G. TruCCo A.C. uGGenTi, r. GerBoni Tel. 051 767003 - Fax 051 768252 11 Modelling of a supersonic Singoli fascicoli: € 39,00 Italia – € 49,00 Estero PDF articoli: € 14,00. The role of the Navy under the accidental release in Oil&Gas Per ordinare: off-shore safety network offshore: characterisation of a www.patroneditore.com source box [email protected] Modalità di pagamento: 17 m.S. mAzzAreSe Versamento anticipato adottando una delle seguenti 65 C. DoGlioni soluzioni: • c.c.p. n. 000016141400 intestato a Pàtron editore – The Italian Coast Guard for the via Badini 12 – Quarto Inferiore – 40057 Granarolo offshore safety Different types of induced dell’Emilia – Bologna – Italia seismicity • bonifico bancario a CARISBO – Agenzia 68 – Via m. Simeone, A. BASCo, A. CriSCuolo, Pertini 8 – Quarto Inferiore – 40057 Granarolo 24 P. SAlATino dell’Emilia – Bologna – Italia – BIC IBSPIT2B; F. CiCCone, e. Priolo, G. TeoFilo, IBAN IT 03 M206385 36850 07400000782T 69 i. AnTonCeCChi, r. lAnAri • carta di credito o carta prepagata a mezzo PAYPAL Green House Gas Emissions from www.paypal.it specificando l’indirizzo oil and natural gas production Seismic monitoring of e-mail: [email protected] underground activities for energy nel modulo di compilazione per l’invio della conferma di pagamento all’Editore. C. mArTinA, S. BonviCini, production: survey of the existing Per ricevere la rivista in abbonamento contattare: 30 v . CozzAni facilities with reference to the Associazione Georisorse e Ambiente Italian monitoring guidelines Tel. 011/0907681 – [email protected] A methodology for the assessment of environmental risk induced by I fascicoli cartacei, se non pervenuti, possono essere G. SolAro, m. mAnzo, m. BonAno, richiesti all’Editore. offshore oil spills Tel. 051/767003 – [email protected] r. CASTAlDo, F. CASu, C. De luCA, 73 v . De novelliS, m. mAnunTA, Pubblicità m. rovere, e. CAmPiAni, e. leiDi, [email protected] S. PePe, P. TizzAni, i. zinno, r. lAnAri 35 A. merCorellA Grafica e impaginazione Ground deformation analysis Exegi Snc - Bologna Natural hydrocarbon seepage in through spaceborne SAR Stampa the Italian offshore interferometry and geophysical Tipografia LI.PE. Litografia Persicetana - modelling San Giovanni in Persiceto, Bologna, febbraio 2018 Riconosciuta dal C.N.R. quale rivista nazionale del m. CoCuzzA, l. SCAlTriTo, settore Geo-Minerario, viene pubblicata sotto gli au- 41 S. Ferrero, S.l. mArASSo, D. n. Cenni, S. GAnDolFi, P. mACini, spici del CONSIGLIO NAZIONALE DELLE RICERCHE Perrone, C.F. Pirri 81 l. Poluzzi, l. TAvASCi Anagrafe Naz. Ricerche 518915NF – ISSN 1121 - 9041 Autorizzazione del Tribunale di Torino, n. 1682 del Innovative technologies for Unconventional methods for 20-11-1964 offshore platforms safety and offshore subsidence monitoring environmental monitoring

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2 Dicembre 2017 Comitato Scientifico GEAM SOMMARIO Scientific Committee Presidente/Chairman Vanni Badino – Politecnico di Torino C. BeneTAToS, G. CoDeGone, D. Di BuCCi, i. AnTonCeCChi, 85 C. DeAnGeli, G. GiAni, A. GoTTA, F. CiCCone, G. TeoFilo, F. TerlizzeSe, George Anagnostou ETH – Swiss Federal Institute F. mArzAno, v. roCCA, F. verGA A. ArGnAni, m. liGi, m. rovere, of Technology, Zurich (Switzerland) Guidelines for the study 125 r. BASili, m. ColTelli, S. loriTo, André Assis Brasilia University (Brazil) of subsidence triggered by B. Borzi, F. GermAGnoli, Guido Badino Università di Torino hydrocarbon production m. Di luDoviCo, G.P. liGnolA, Monica Barbero Politecnico di Torino A. ProTA Giovanni Pietro Beretta Università di Milano The SPOT project (potentially Paolo Berry 97 P. mACini, m. FerrAri, G. PiSConTi triggerable offshore seismicity Nuh Bilgin Istanbul Technical University (Turkey) and tsunamis): a first appraisal Lorenzo Brino TELT, Torino Monitoring of drilling operations of the possible impact of oil and gas platforms on the seismic and Marilena Cardu Politecnico di Torino in the Italian offshore by means of Bernardino Chiaia Politecnico di Torino virtual “black boxes” tsunami risks along the Italian coasts Marina Clerico Politecnico di Torino Raffaello Cossu Università di Padova S. GrAnDi, D. AirolDi, r. CiAnellA, C. BrAmBillA, Masantonio Cravero i. AnTonCeCChi, S. CAmPoreAle, F. CAPPelleTTi, v. CozzAni, Riccardo Crivellari Rappresentante Ordine Ingegneri A. DAnelli, W. DA riz, 132 101 A. CrivellAri, P. mACini, S. mArAn, della Provincia di Torino m. De niGriS, P. GirArDi, A. TuGnoli, A. SArACino, F. TerlizzeSe Valerio De Biagi Politecnico di Torino v. mArTinoTTi, n. SAnToCChi Key performance indicators Domenico De Luca Università di Torino Planning for a safe and and multicriteria approach for Marina De Maio Politecnico di Torino sustainable decommissioning of measuring safety of offshore offshore hydrocarbon platforms: Oil&Gas facilities Anna Maria Ferrero Università di Torino complexity and decision Mauro Fornaro support systems. Preliminary Le rubriche di GEAM Massimo Guarascio Università di Roma “Sapienza” considerations Pietro Jarre Global studio TCA Tips on Occupational Vincent Labiouse Ecole Polytechnique Federal de Lausanne (Switzerland) i. AnTonCeCChi, S. CAmPoreAle, 138 Safety and Health – OS&H 109 W. DA riz, S. GrAnDi, v. mArTinoTTi, m. PATruCCo, l. mAiDA, P. FArGione Annalisa Lantermo ASL TO1 n. SAnToCChi Jakob Likar Lubiana University (Slovenia) Productive state of the Oil&Gas 143 DIATI News Andrea Lingua Politecnico di Torino platforms: a classification proposal Stefano Lo Russo Politecnico di Torino for the mining statistical review Ingegneria del petrolio e mineraria Francesco Luda di Cortemiglia al Politecnico di Torino Fabio Luino IRPI - RUOS - Torino CNR Paul G. Marinos National Technical University of l. Serri, D. BerTAni, F. ColuCCi, Atti dell’Associazione Athens (Greece) 114 S. GuASTellA, e. lemBo 145 Luisa Teresa Maida Politecnico di Torino Use of renewable energy in Daniele Martinelli Politecnico di Torino offshore Oil&Gas platform f or Mario Patrucco Politecnico di Torino power supply optimisation Sebastiano Pelizza Politecnico di Torino Mario Pinzari Università Roma 3 120 S. CAmPoreAle, i. AnTonCeCChi, Enrico Pira Università di Torino A.S. BoneTTi, F. CeruTi Marina Pirulli Politecnico di Torino LNG loading/downloading Raymond Sterling (USA) and circular economy: the Bartolomeo Vigna Politecnico di Torino opportunities related to the Mariachiara Zanetti Politecnico di Torino new legislation and the reuse of Shu Lin Xu Geodata S.p.A. – Torino Oil&Gas platforms In copertina: Piattaforma Barbara T2, ubicata nel mare Adriatico e operata da Eni, per la compressione del gas naturale. Struttura reticolare a 4 gambe, unita in unica struttura con le piattaforme Barbara C e Barbara T. Foto: DGS UNMIG

Dicembre 2017 3 editoriale mise

Editoriale MISE

La cultura storica imprenditoriale del Paese, la presenza di eccellenze tecnologiche e scientifiche ed il carattere pione- ristico del settore upstream hanno da sempre contribuito a configurare le operazioni di ricerca e coltivazione di idrocarburi a mare come attività in cui l’innovazione gioca un ruolo fondamentale, garantendo altissimi standard di sicurezza. Volgendo uno sguardo alla storia che ha portato il settore idrocarburi ad avere un ruolo fondamentale nello sviluppo tecnologico del Paese, ci si accorge che già prima degli anni ’60, in atti parlamentari, l’ENI ebbe «il vanto di essere stato il primo operatore in Europa ad eseguire ricerche del genere. […] Le perforazioni […] ebbero inizio il 26 marzo 1959 con il pozzo Gela Mare 21 eseguito con impianto montato sulla piattaforma mobile Scarabeo», di tecnologia italiana. Nello stesso periodo, per quanto riguarda l’esplorazione e la produzione del gas naturale, l’Italia occupava il quarto posto dopo Stati Uniti, Venezuela e Canada, grazie ai giacimenti della Val Padana che producevano 3,6 miliardi di metri cubi di metano all’anno. In questo contesto è utile rilevare che il consumo energetico pro-capite era molto basso pur mostrando una forte potenzialità di incremento della domanda a seguito della diffusione di massa degli elettrodome- stici e delle autovetture che pian piano si stavano imponendo sul mercato. Con lo stesso spirito di 60 anni fa, che ha portato l’industria italiana a svolgere un ruolo da protagonista nel settore, la Direzione Generale per la Sicurezza – Ufficio Nazionale Minerario per gli Idrocarburi e le Georisorse (DGS UNMIG del Ministero dello Sviluppo Economico) sta orientando gli sforzi, la ricerca e lo sviluppo tecnologico nella direzione delle nuove politiche energetiche del Paese in adempimento agli obiettivi strategici individuati dal documento di Strategia Energetica Nazionale (SEN) e coerentemente con le proprie competenze nel campo della sicurezza e del controllo delle operazioni. Infatti, fin dalla nascita dell’UNMIG nel lontano 1957, una sezione del Bollettino Ufficiale degli idrocarburi era dedicata alla ricerca. Nel rispetto di questa tradizione e nell’impulso di rilancio dell’attenzione normativa al tema “sicurezza” con De- creto Legislativo 145/2015 che ha recepito la Direttiva europea 2013/13/EU, si inquadra il “Network per la sicurezza offshore”: una realtà scientifica altamente specializzata e dinamica che si occupa di sviluppare risultati applicativi per il miglioramento della sicurezza delle attività minerarie ed energetiche a mare. Si tratta di un sistema formato da Forze Armate e importanti Enti di Ricerca ed Università, gestito e monitorato dalla DGS UNMIG che ad oggi ha articolato un programma di attività sviluppato su sei linee di progetto: – definizione di un Indicatore di sicurezza delle attività offshore; – miglioramento della conoscenza e del monitoraggio delle attività anche attraverso l’innovazione tecnologica; – definizione di procedure e best practices nel settore della sicurezza delle attività minerarie ed energetiche; – gar anzia del dialogo e della trasparenza sul territorio attraverso l’applicazione di strumenti di comunicazione con- divisi; – studio della sismicità potenzialmente innescabile offshore e tsunami – Progetto SPOT; – definizione di un programma sicuro e sostenibile di dismissione degli impianti e/o multiuso delle piattaforme – Pro- getto “Safe and Sustainable Decommissioning”. Le attività del “Network” così ripartite si configurano nell’ambito di un progetto più ampio della DGS UNMIG volto a supportare scientificamente le attività istituzionali ed amministrative indagando temi all’avanguardia per il settore. In questo processo si riconosce una efficace evoluzione della conoscenza alimentata dalle costanti interazioni tra una moltitudine di esperti quali tecnici, ricercatori e professori. Già dopo i primi due anni queste sinergie iniziano a fornire prodotti tangibili e concreti: creazione di banche dati, realizzazione di software specialistici, analisi del rischio e molto altro ancora. Così da 4 collaborazioni avviate nel 2014 siamo passati a 15 collaborazioni nel 2017. Questa monografia dedicata al “Network per la sicurezza offshore”, pubblicata dalla rivista di Geoingegneria Ambien- tale sotto il patrocinio e con il contributo della DGS UNMIG, fa parte delle numerose azioni intraprese dalla stessa DGS UNMIG per la diffusione e l’informazione sui risultati delle attività. In questo numero speciale ci è sembrato quindi quanto mai opportuno mettere in luce e diffondere le singole ricerche unendole nella visione complessiva della Direzione. A questo scopo l’ordine seguito nella redazione dell’indice intende fornire al lettore il fil rouge della gestione del Network mettendo in risalto prima di tutto la necessità di migliorare il dialogo e la trasparenza sul territorio e con gli stakeholders attraverso una strategia di comunicazione condivisa basata sull’utilizzo di strumenti di divulgazione che adoperino un linguaggio semplificato (cfr. Di Simone et al.). Nel

4 Dicembre 2017 editoriale mise raggiungimento di questo obiettivo l’impegno degli enti di ricerca è fondamentale ed è per questo che la Direzione si impegna a presentare all’esterno tutte le conoscenze, gli studi e le applicazioni previste dai progetti consentendone, anche attraverso il web, l’accesso agli utenti che vogliono essere maggiormente informati sui temi di competenza della Direzione ed in particolare su quelli relativi ai diversi progetti (ad esempio anche tramite la realizzazione di un Rappor- to annuale e l’elaborazione di rapporti periodici). Anche la proposta di realizzazione di un indice per la sicurezza delle attività offshore affonda le sue ragioni nell’ado- zione di uno strumento che consenta a tutti, anche ai non esperti, una lettura chiara dello stato di salute degli impianti a mare. Infatti, la Direzione ha dato avvio al “Progetto Indicatori” per monitorare l’evoluzione negli anni dello stato di sicurezza delle operazioni di coltivazione di idrocarburi che si svolgono nei mari nazionali e darne efficace rappresentazione ad un pubblico più ampio, rispetto a quello dei soli addetti ai lavori. Il progetto mira a definire un set di indicatori prestazionali (Key Performance Indicators – KPI), in grado di descrivere in modo esaustivo gli aspetti salienti della sicurezza dell’upstream offshore, e a condensare ulteriormente le informazioni dei differenti KPI in un unico indicatore di sintesi (Composite Indicator – CI ) che coniughi rigore nella formulazione e semplicità nella lettura. In questo numero viene presentato un contributo (Cianella et al.) riguardante un primo prototipo del progetto, definito su 3 KPI ma attualmente oggetto di una successiva espansione, orientato a costituire il nucleo di base degli indicatori dai quali – a regime – sarà calcolato l’indicatore composito nazionale di sicurezza. Grazie alle caratteristiche di modularità della procedura messa a punto per la costruzione dell’indicatore composito, esso è già predisposto per recepire opportunamente i risultati delle differenti collaborazioni scientifiche del Network. Non è quindi casuale la scelta di inserire l’articolo sul “Progetto Indicatori” nella parte finale di questo volume, veden- do in esso un potenziale strumento di summa delle diverse azioni intraprese dalla Direzione in tema di sicurezza. La sicurezza è ovviamente un risultato che di anno in anno la Direzione ha sempre perseguito attraverso i suoi uffici pe- riferici (Sezioni UNMIG) e il Laboratorio Chimico Mineralogico, predisponendo ispezioni e controlli sull’integrità delle infrastrutture e sulla sicurezza delle persone: ad esempio, Dei et al. presentano a questo proposito le attività di collaborazione con la Marina Militare. Poiché però la sicurezza delle attività minerarie oggi richiede anche azioni per la prevenzione e mitigazione dei rischi, per i quali è necessario disporre di conoscenze scientifiche adeguate e di strumenti con prestazioni idonee all’ottemperamento delle prescrizioni ormai sempre più restrittive, il gruppo di ricerca del Network sul tema monitoraggio sta predisponendo studi necessari a migliorare la conoscenza di molti fenomeni ad oggi ancora poco conosciuti quali la sismicità indotta (Doglioni et al.), la subsidenza (Benetatos et al., Cenni et al. e Solaro et al.), la dispersione di inquinanti naturali (e.g. Rovere et al.) o, in relazione alle attività effettuate, la verifica delle infrastrutture e la messa a punto della tecnologia necessaria a prevenire eventuali effetti indesiderati (Agate et al., Bonvicini et al., Pirri et al.). In questo numero saranno presentati anche studi di ricerca applicata alla gestione dei monitoraggi quali, ad esempio, il censimento delle reti di monitoraggio (Ciccone et al.). Questo genere di ricerche è soprattutto finalizzato all’approfondimento di tematiche scientifiche complesse per l’applicazione dei monitoraggi previsti dagli “Indirizzi e Linee Guida (ILG) per il monitoraggio della sismicità, delle deformazioni del suolo e delle pressioni di poro” pubblicati dal Ministero dello Sviluppo Economico nel 2014, ad oggi le migliori pratiche italiane nel settore. Analogamente alla stesura degli ILG, lo sviluppo di pratiche e procedure per disciplinare tematiche di alto contenuto scientifico-tecnico è ormai un obiettivo che anche le Amministrazioni si devono porre, seppur con i pochi mezzi a disposizione. Un importante contributo deve arrivare necessariamente dalla comunità scientifica. In questi due anni la Direzione è riuscita a stendere un testo di proposta, attualmente al vaglio del Comitato Offshore, di “Linee Guida tecniche per la redazione della Relazione Grandi Rischi” così come previsto dalla Direttiva offshore (2013/30/UE), recentemente recepita in Italia attraverso il D. Lgs 145/2015. Con un lavoro coordinato fra la Direzione e il Politecnico di Torino si è predisposto uno strumento che si rivolge agli operatori, ai quali fornisce una indicazione dei contenuti minimi della Relazione sui Grandi Rischi legati all’attività di ricerca e coltivazione mineraria offshore, ma anche all’Autorità Competente per la valutazione delle analisi proposte dall’operatore. Peraltro la collaborazione con enti sul tema delle best practices abbraccia molti altri campi che riguardano anche l’utilizzo di strumenti black box per la registrazione in continuo dei parametri di perforazione (Macini et al.) e le migliori pratiche per la modellazione di sversamenti di gas a mare (Bonvicini et al.) o per la modellazione CFD per il rilascio supersonico accidentale in ambito Oil&Gas (Carpignano et al.). Gli studi del Network sono poi dedicati anche al tema delle dismissioni degli impianti a mare. Con riferimento a questo tema di ricerca il programma della DGS UNMIG è caratterizzato da una forte interdisciplinarità. L’attività è articolata in vari progetti che spaziano dagli aspetti tecnologici, ambientali, giuridici e socio-economici al fine di contribuire alla definizione di dismissioni e smantellamenti sostenibili o di supportare la valutazione per il riutilizzo degli impianti ad altri scopi. I contributi raccolti in questo numero rappresentano il quadro di lavoro dei vari gruppi di ricerca, con alcuni preliminari approfondimenti i cui risultati presentano caratteri distintivi anche nel quadro internazionale. Il primo articolo si concentra sulla definizione di una metodologia per l’analisi tipologica delle piattaforme al fine della trasparenza dell’Amministrazione nella comunicazione dei piani di dismissione (Antoncecchi et al.); il secondo contributo si focalizza invece sugli aspetti dell’analisi dell’applicazione della Multi Criteria Analysis per il supporto alla decisione tra opzioni d’uso alternative delle piattaforme e avvio alla dismissione degli impianti (Grandi et al.). Proprio il tema degli usi

Dicembre 2017 5 editoriale mise alternativi è tra quelli che hanno stimolato l’attività di ricerca giuridica e socio-economica sul tema del riciclo-riuso e della circular economy anche nel settore dell’energia. Una delle opzioni che appaiono più percorribili dal punto di vista economico e dell’assetto normativo è proprio quello dell’uso delle piattaforme per il carico e scarico del GNL come combustibile alternativo delle navi (Camporeale et al.). Sempre di grandissima attualità è, infine, la necessità di un approfondimento scientifico sulla sismicità potenzialmente innescata dalle attività antropiche, tema di frontiera dal punto di vista scientifico sia in Italia che all’estero. La Direzione, recependo le raccomandazioni della Commissione Grandi Rischi, ha avviato su questo argomento nelle aree offshore un percorso di studio, avvalendosi anche del supporto tecnico del Dipartimento della Protezione Civile. I primi studi scientifici intrapresi sono organizzati in un progetto dal nome “Sismicità Potenzialmente innescabile Offshore e Tsunami” (progetto SPOT), condotto da CNR-ISMAR, INGV, EUCENTRE e ReLUIS (Di Bucci et al.). L’obiettivo del progetto, in questa prima fase, riguarda la caratterizzazione della sismicità naturale connessa all’eventuale presenza di sorgenti sismogeniche in prossimità di aree che ospitano attività antropiche in mare. Verrà analizzata l’effettiva esistenza di tali sorgenti e modellati i potenziali scenari di impatto sulla costa dovuti a una loro attivazione, includendo anche i maremoti eventualmente indotti. Questo primo screening è propedeutico a futuri approfondimenti, che vedranno il coinvolgimento degli operatori al fine di tenere conto anche dei dati di produzione in caso la modellazione combinata dei terremoti e degli tsunami naturali indicasse un impatto rilevante lungo le coste.

Concludendo, il Network è una realtà nazionale ricca e altamente qualificata, in linea con i più attuali modelli europei di gestione della ricerca, che si affaccia su tematiche di grande interesse economico, sociale e ambientale cercando di dipanare attraverso la conoscenza tecnico – scientifica il groviglio di informazioni spesso poco documentate che creano tensione sul nostro territorio a svantaggio di tutti.

Il Direttore Generale DGS – UNMIG Franco Terlizzese Il coordinatore tecnico-scientifico Ilaria Antoncecchi I responsabili dei progetti Roberto Cianella Ilaria Antoncecchi Marcello Strada Chiara Di Simone Silvia Grandi Il referente del Dipartimento della Protezione Civile Daniela Di Bucci

6 Dicembre 2017 ambiente

C. Di Simone* Dialogue and transparency A. Di Gregorio** for maximum safety: F. Terlizzese* * Ministry of Economic Development, Directorate General for Safety of Mining preliminary analysis of and Energy Activities – National Mining Office for Hydrocarbon and Georesources communication strategy by ** University of Milan – Bicocca DGS UNMIG 1. Introduction In recent years, the debate on the safety of activities related to energy production, mainly in respect to the issue of environmental impact and that of the consent of citizens and administrations of the In recent years, the debate on the territories involved, has been followed by national and local media. safety of activities related to energy The Directorate General for Safety of Mining and Energy Activities (DGS UNMIG) Ministry of Eco- production, mainly from an envi- nomic Development, therefore, felt the need to initiate channels of communication of its activity for ronmental point of view, has been maximum safety, based on dialogue with all stakeholders, and the commitment to total transparency. very lively and followed by the me- To this end, CRIET – University of Milan Bicocca, in its role as partner of the DGS UNMIG, has dia, both at national and local levels, carried out a preliminary analysis aimed at launching a communication program by the Directorate- in the territories affected by energy General on subjects of its strict competence. activities that do not have the con- The analysis focused on the reference context in which the activities of the DGS UNMIG, both natio- sent of the citizens and local admini- nally and internationally, are included, with particular reference to the criticality of territorial resistan- strations. ce; the role of the web and its influence in territorial debates; on the references that characterize The Directorate General for Safe- the nature of the debate in Italy; on the elements of a strategic approach related to communication. Preliminary analysis by CRIET has identified a number of strategic approaches closely related to ty of Mining and Energy Activities the field of communication such as: the need to anticipate and foresee dissent, seeking as much as (DGS UNMIG) – Ministry of Eco- possible to interact with stakeholders involved; the importance of the credibility and authority of the nomic Development has therefore people who carry out the actions and supply the information; the need for transparency and clarity warned of the need to launch a com- in sharing information; the promotion of greater collaboration and dialogue between the central and munication path of its activity for local administrations, to overcome, or rather to prevent, territorial conflicts in a structured way. maximum safety based on dialogue with all stakeholders and with the Dialogo e trasparenza per la massima sicurezza: analisi preliminare per un percorso commitment to transparency. di comunicazione della DGS UNMIG. Negli ultimi anni il dibattito sulla sicurezza delle attività This article presents the outcome energetiche, principalmente relativamente al tema dell’impatto ambientale e a quello del consenso of a preliminary analysis that CRIET di cittadini e amministrazioni dei territori coinvolti, ha interessato molto i media nazionali e locali. – University of Milan Bicocca, in its La Direzione generale per la sicurezza anche ambientale delle attività minerarie ed energetiche presso il Ministero dello Sviluppo Economico (DGS UNMIG) ha quindi avvertito la necessità di role as partner of the DGS UNMIG, avviare un percorso di comunicazione della propria attività per la massima sicurezza improntato al has implemented in order to allow dialogo con tutti gli stakeholders e con l’impegno della massima trasparenza. the launch of a communication pro- Per rispondere a questa esigenza, il CRIET (Centro di Ricerca Interuniversitario in Economia del gram by the DGS UNMIG on the Territorio) – Università di Milano Bicocca, nel suo ruolo di partner della DGS UNMIG, ha realizzato topics of its competence. un’analisi preliminare finalizzata all’avvio di un programma di comunicazione da parte della Dire- The preliminary analysis of the zione Generale sui temi di sua stretta competenza. development of the action plan fo- L’analisi si è focalizzata sul contesto di riferimento nel quale si inseriscono le attività della DGS cuses on the reference context in UNMIG, sia a livello nazionale che a livello internazionale, con particolare riferimento alle criticità which the activities of the DGS relative alle resistenze territoriali; sul ruolo del web e della sua influenza nei dibattiti territoriali; sui UNMIG are integrated, both natio- riferimenti che caratterizzano la natura del dibattito in Italia; sugli elementi di approccio strategico nally and internationally, with par- legati all’ambito della comunicazione. ticular reference to the criticality of L’analisi preliminare svolta dal CRIET – Bicocca ha consentito di individuare una serie di elementi di approccio strategico strettamente legati all’ambito della comunicazione, quali: la necessità di territorial resistance; the role of the anticipare e prevedere il dissenso, cercando il più possibile di interagire con i portatori di interesse web and its influence in territorial sul territorio coinvolto; l’importanza della credibilità e dell’autorevolezza dei soggetti che realizzano debates; the references that cha- le azioni e veicolano le informazioni; l’esigenza di trasparenza e chiarezza nella condivisione delle racterize the nature of the debate in informazioni; la promozione di maggiore collaborazione e dialogo tra l’amministrazione centrale e Italy; on the elements of a strategic quelle locali, per superare, o meglio per prevenire, in maniera strutturata le conflittualità territoriali. approach related to communication.

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 7-10 7 environment

2. The context of reference bons to the production of energy and does not allow the synthesis of from biogas or biomass, and so on. a Center-Suburban decision, even DGS UNMIG’s project for com- Very often the episodes of conten- when unpopular. munication on safety issues is part tion arise from a lack of communi- of a general context in which bu- cation and the absence of a proper reaucratic chaos and competing participatory process of the commu- legislation between the State and nities affected by a new project. So- 3. The role of the web and the Regions generate, in many ca- metimes, the exploitation by some its influence in the debate ses, tensions and conflicts in a way people who, based on the factual it would require serious planning and specific knowledge of the public The analysis carried out focused and analysis. The case of the six re- and the members of the Public Ad- on the role of the web and its in- ferendums against hydrocarbons ex- ministration, disseminate incorrect fluence in the debate, given that, on ploration, research and extraction or partial information for personal the one hand, opposition and pro- activities presented by ten Regions consent. tests are increasingly organized on on September 30, 2015 is an emble- The main causes of territorial the web, on the other, that the Pu- matic example. conflict were represented by: blic Administration, both national There is also a lack of incisiveness – poor communication and lack of and local, often lack the right skills in the messages transmitted by na- a structured participatory process; to use the new media properly. tional and local Institutions, which – late and unreliable involvement Indicative, in this sense, was the should instead focus much more on of social actors, often in response deepening of the case NO DRIL- the enhancement of their role of to media stress and cost-effective LING, a phenomenon that was born reference and safeguard the popu- cost-cutting studies; locally and then diffused through lation. Ineffective communication, – propensity to see greater envi- the web nationwide. In particular, it in fact, leads to a mistrust that can ronmental risks than real ones. was noted that the element that cau- lead to a more or less instrumental The common denominator of sed the dispute to spread – also found opposition, and in many cases block conflict is, however, the perception by the analysis of traditional me- or delay any hypothesis of infrastruc- by the communities of how taxes are dia – was a great deal of caution by ture or industrial projects. invested and of which specific fun- both oil companies and institutions, The analysis showed that Insti- ctional needs of the works are ad- which, fearing exploitation, pre- tutions struggle to communicate dressed, without taking due account ferred not to expose. The described and interact with each other and of the sensibilities and expectations attitude can be considered as one of with other stakeholders, with the of the population and of certain eco- the causes of the loss of credibility result that often the perception of nomic sectors (e.g. tourism, agricul- towards citizens who no longer have the work prevails over the technical ture, etc.). scientific, political, institutional content: thus the communication The numerous episodes that reference points, approaching en- about projects is crystallized and have been observed over time have vironmental issues with widespread defined not by those who supported highlighted how the relationship mistrust. them (as it should be), but by those between the State and the Regions The analysis concludes that the who are opposed, not so often with has a considerable weight in cri- web represents a great opportunity technical, economic, environmental tical situations. Aside from some for institutions and stakeholders as reasons entirely but many times wi- enlightening cases, in fact, it was well as an exceptional expression of thout foundation or rationality. found that the Local Public Admi- information democracy, but at the In recent years there has been nistration – in their political and same time there are numerous risks exponential growth of more or less administrative components – often due to the rapid and uncontrolled spontaneous protests by citizens do not know the possible participa- vein of any fake news (often mani- and organizations against sensitive tory pathways to inform and invol- pulated on purpose, sometimes con- infrastructure projects. In general, ve citizens and stakeholders on new veyed in good faith). For example, there have been situations of gene- projects on their territory. There was reference is made to the ability to ralized and widespread disputes that a frequent lack of decision-making share content from non-controlled have affected the diversification of capacity on the part of local autho- sources on social networks (Facebo- the various initiatives, leveraging rities that, in the face of important ok, Twitter, etc.). It has been obser- excitement: from new highways to and often contested or debated choi- ved that, in fact, with a clever viral geothermal power plants, from wind ces, “decide not to decide”. In this propagation scheme, it is possible power plants to waste-to-energy way, the local institution renounces to reach tens of thousands of users plants, from research on hydrocar- its role as a guide to the territory in very short time with unfounded

8 Dicembre 2017 ambiente news releases or information packa- in the direction of greater adherence Specifically, the following ele- ges. to the current commitment of Italy ments emerged from the analysis The analysis also revealed that to energy transition. that were the main reference points the logic of overcoming competen- An additional element that ma- for changing the priorities of the ince may sometimes descend from the kes the communication field criti- ternational context: phenomenon of the spread of fake cal is linked to the credibility of the – Paris Climate Change Agree- news: the social evolution of the web subjects involved in the debate. It is ment, defined at the end of 2015 and the concomitant growing di- of utmost importance that informa- in COP21 (21st Conference of the strust towards the scientific commu- tion comes from a proven source of Parties), which have strengthe- nity is in fact leading to a dangerous proven reliability and independen- ned the orientation towards re- overvaluation of agent information ce. newable energy sources; COP22 or influencers who express themsel- Equally important is the point of November 2016 examined the ves on the most disparate themes of attention that requires scientific, implementation of the Paris Pact; and who in reality would not have technical and economic demands – Sustainable Development Goals the title to represent a source. that come from the territory. In fact, (SDGs), defined in 2015 and ex- information must be calibrated on piring 2030; responses to perceived needs as re- – the strategic lines outlined by the levant to the territory, and not just European Union, which aims to 4. References to the debate to those that the proposing subject guide the international transition on the hydrocarbon sector considers significant because they towards a cleaner and more effi- in Italy value the project. In this sense it has cient energy system. been noted that it is essential to bu- These innovations have been wi- ild a communication strategy by ope- dely addressed and commented by The analysis of the debate in Italy ning up the comparison, especially the Italian media, precisely because on exploration and production of to groups (small) homogeneous of they have recently introduced the hydrocarbons has allowed to identify subjects (some Municipalities, some need for a major revision of the Na- some of its main elements, which are Regions) so that they can ask que- tional Energy Strategy but also of the presented below. stions and get direct and personal re- company’s policies on energy supply Certainly, in a difficult and un- sponses, establishing a constructive and environmental sustainability. certain macroeconomic context, trust relationship. such as the Italian one, the energy With reference to all the ele- system and the supply chain model ments that characterize the debate, of raw materials become the neu- it emerged that information should 6. The intervention strategy ralgic point for the recovery of the be understood as the relationship competitiveness of the more gene- that builds trust, and not just as the Preliminary analysis has made it ral economic system. Consequently, passage of content from one subject possible to identify a number of stra- the primary challenges are related to to another. tegic approach elements closely re- price efficiency as a result of the fact lated to the area of communication, that energy prices for businesses and which are summarized below: households in Italy are higher than – Need to anticipate and foresee those of other European countri- 5. The international disagreement, seeking as much as es; to the security of energy supply, context possible to interact with stakehol- which is not optimal at peak times, ders in the area involved: public especially for gas, and creates high The international context is cha- administrations, by virtue of their dependence on fossil fuel imports; racterized by the need to manage institutional role; individual citi- the existence of small business ope- the energy transition towards a low- zens, who tend to be involved in rators in financial and economic carbon economy and the prevalence decision-making; local and natio- difficulties. However, in the media of global warming strategies. Italy’s nal environmental associations; debate, the strategic approach from strategic guidelines are consistent trade unions; the political strata a national perspective is scarcely with international guidelines, in that oppose the decisions of the present, given that the contents of particular with the prospect of de- incumbent administration, deve- the National Energy Strategy are carbonization and transition to re- loping a public debate sometimes still little known, despite the ex- newable sources, leading to further of considerable controversy. Ex- pectation, strongly supported by the public discernment on the need for pecting the dynamics in the field Government in office, of its revision mining development. with a proactive and preventive

Dicembre 2017 9 environment

communication strategy, as well only useful to create a contrary if not open, a confrontation with as reactive, becomes a determi- position. Citizens often end up the Regions and other local repre- ning factor. looking for information on their sentative bodies that can to deter- – Authenticity – Another critical own, and the data they have is mine more critically the criticali- element is the credibility and au- often from unofficial channels ties, tones, and the most effective thority of the actors who carry out (which become the source of in- ways in defining the strategy. the actions and deliver the infor- formation). These evidences have enabled mation. It is of utmost importan- – Greater Collaboration at Central DGS UNMIG to clarify the direc- ce that information comes from a and Local Levels – The participa- tions to follow to give substance to proven source of proven reliabili- tory process aims to represent, as its choice of innovation in the com- ty and independence. far as possible, the positions, the munication approach on issues rela- – Transparency – Information sha- general interests and the parti- ted to the safety of energy activities, ring is often difficult and content cular needs of strategy and terri- including through the involvement is very often readable by trouble torial protection as comprehen- of all partner organizations in its seekers. This means that content sively and explicitly as possible. Directorate-General , from which can be “distorted” and interpre- To overcome, or rather to prevent a fundamental contribution to the tation is not functional to real- territorial conflict in a structured transparency of the results of rese- ly understanding the issues, but way, it is important to maintain, arch is expected.

10 Dicembre 2017 ambiente

P. Dei* The role of the Navy under A. Falcone** the off-shore safety network G. Trucco*** * Stato Maggiore Marina – Ufficio Attività Duali e Collaborazioni As part of the collaboration with the Ministry of Economic Development (MISE), Directorate-Gen- Esterne ** Comando delle Forze di Contromisure eral for Safety of mining and energy activities – National Mining Office for Hydrocarbons and Mine – Capo Ufficio Studi e Supporto Georesources (DGS-UNMIG), the Italian Navy in its current role effectively contributes to the holistic *** Raggruppamento Subacquei ed management of maritime-related issues on offshore safety. Incursori – Capo Nucleo Pubblica As a result of the growing relevance of and strong interest in offshore safety in Europe and world- Informazione wide, the DGS-UNMIG felt the need to start a series of collaborations with Universities, Research Centers and Public Bodies was essential. To this end, the agreement between the Navy and the DGS-UNMIG has ratified the tasks the Navy has always carried out, which are closely related to civil life with focus on the maritime environment and has been aimed at improving scientific knowledge to monitor offshore operations. Thus, the following paper describes the nature of the navy and its structive role that the Italian Navy role in the safety network of the aforementioned operations by describing the tasks and activities it has in contributing to a more inte- has engaged in since its agreement with DGS-UNMIG. grated and systemic management of Keywords: Italian Navy (ITN), MISE / DGS-UNMIG, dual use, offshore safety, environment. the precious resources that the maritime environment offers. Il ruolo della marina militare nell’ambito del network per la sicurezza offshore. Moreover, maritime vocation in Nell’ambito delle collaborazioni del Ministero dello Sviluppo Economico (MISE), Direzione Generale our nation is a resource for the fu- per la Sicurezza anche ambientale delle attività minerarie ed energetiche Ufficio Nazionale Mine- ture; this is the century of the blue rario per gli Idrocarburi e le Georisorse (DGS-UNMIG), la MM ha messo a disposizione le proprie economy. The European Union also capacità e competenze fattivamente contribuendo alla gestione olistica di una dimensione cruciale speaks of blue growth as a key fac- come quella marittima, da cui dipendono fortemente la nostra crescita e prosperità. tor for a country’s sustainable deve- A valle della crescente rilevanza e del forte interesse nel panorama europeo e globale, in merito alla lopment. The marine and maritime questione della sicurezza ambientale delle attività offshore, la DGS-UNMIG ha ritenuto strategico avviare, a partire dal 2014, una serie di collaborazioni con Università, Enti di ricerca e Corpi dello sectors are crucial for the country Stato. and its sustainable growth. L’accordo tra la MM ed il MISE / DGS-UNMIG ha sancito ciò che la Marina Militare compie da The sectors are fundamental to sempre grazie ai compiti di istituto che, per loro natura, sono strettamente connessi anche al mondo global economy, since 90% of trade civile, con particolare riferimento al complesso ed articolato contesto dell’ambiente marittimo. happens by sea and in the last decade, Le collaborazioni finora avviate hanno portato a risultati positivi nell’ambito dei controlli e nel mi- 75% of the countries have increased glioramento delle conoscenze in campo scientifico per il monitoraggio dell’ambiente marino e delle their maritime capacity and increa- operazioni offshore. sed the size of the merchant fleets as Parole Chiave: Marina Militare, MISE / DGS-UNMIG, attività duali, sicurezza offshor, ambiente. well as investing in port and offshore infrastructures. The sea, which is a common good of humanity, is the- 1. Introduction Over the years, the Italian Navy refore vital for Italy, for Europe and has constantly tried to meet the new for the world, and the Italian Navy The Italian Navy – along with needs of defense and security in ma- (ITN) has the primary function of the Italian Army, the Italian Air ritime terms while gradually consoli- guaranteeing security, free trade and Force and the Carabinieri Corps – is dating its international role. free use. Our country today is vital- a component of the Italian Armed The Italian Navy is engaged not ly dependent on the maritime sector Forces. Acting upon the sea and only above and under the sea but in terms of: supply of raw materials, from the sea, the Italian Navy con- also in the sky and on land, to provi- energy resources, export of products tinuously ensures the necessary re- de its ability to operate in a multidi- to international markets, exploita- adiness, both in the proper defense mensional and multidisciplinary en- tion of marine resources, and econo- roles and in carrying out other tasks vironment: its approach is based on mic use of the coasts. within inter-institutional coopera- well-known principles of inter-force Several researchers and analysts tion frameworks, including Italy’s integration, inter-institutional coo- have described current times as that contribution to international com- peration, multinational interopera- of the “blue century” and the “blue munity efforts for global stability and bility and interagency collaboration economy”, the concepts that under- for the safe and secure operations of with a “Dual Use” philosophy. pin the European Commission’s stra- offshore activities. In this “Dual Use” lays the con- tegy developed on so-called “blue

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 11-16 11 environment growth” as a key factor for a sustaina- within the provisions of Art. 115, ly called Smart (Service-oriented ble development of the region. Surveillance at sea, of Legislative infrastructure for MARitime Traf- The Navy provides protection of Decree no. 66/2010 (Code of Mili- fic tracking) MISE; maritime traffic routes, chokepoints tary Order): “The Navy carries out – Maritime Surveillance, aimed and ports of access to the ports, na- … surveillance for the prevention at creating a “maritime picture”, tional production system and natio- of pollution of marine waters by oil built at the CINCNAV facilities nal maritime transport. and other harmful substances into which collects all the informa- The collaboration between the the marine environment and the in- tion and data made available by ITN and the Ministry of Economic vestigation of offenses relating to the the various civil and military au- Development (MISE), Directorate- Law”. thorities involved in maritime General for Safety of mining and This co-operation represents a activities. This, with the final aim energy activities – National Mining perfect match between the dual use to highlight the activities of all Office for Hydrocarbons and Geore- capabilities of Navy assets and the research units operating in Italian sources (DGS-UNMIG) is a concrete institutional requirements of the waters (in the three years many tool for monitoring and controlling: General Directorate, optimizing in controls have been carried out, up facilities and areas of possible exploi- fact, the use of resources by reducing to 106 hydro-oceanographic rese- tation of the subsoil, safety and envi- duplication of material, assets and arch ships in 2016); ronmental protection, as well as the capabilities. At the same time it al- – patrol of the marine areas open to inspection of underwater structures lows to increase the safety of offshore prospection, exploration and pro- for offshore activities. activities in terms of preventive ac- duction of hydrocarbons with air As part of the collaboration with tions within a security contest, as- and naval assets, in order to pre- the DGS-UNMIG for the safe and suring environmental protection in vent and detect unauthorized re- secure operation of offshore activi- the areas affected by offshore activi- search or encroachments by ripa- ties, the ITN made its expertise avai- ties, the protection of state interests rian States, verifying the presence lable to: with actions of control to prevent of hydrocarbon pollution and – ensure monitoring and control possible unauthorized activities and/ their possible correlation with of offshore platforms and marine or trespassing by other States. offshore activities. These activi- areas of possible exploitation, in In order to ensure a smooth and ties are undertaken with targeted order to avoid and detect unau- continuous coordination and fitting missions or in conjunction with thorized activities both with oc- action for the development of the re- other missions of ITN vessels casional patrolling of maritime quired work, the ITN maintains the operating in these areas. While areas, with electronic surveillan- contingent availability and presence contributing to the compilation ce of the same zones through the of its staff c/o the DGS-UNMIG. of the maritime picture, these ac- centralized information flow va- tivities ensure: lued at the Commander in Chief – localization, identification and of the Fleet (CINCNAV) facili- monitoring of research units; ties; 2. Activity and Results – verification of compliance of the – perform inspections to facilities, safety zones established around systems and underwater structures There have been numerous acti- offshore installations with the through the Italian Navy Naval vities carried out over the last three Maritime Authority ordinances; assets equipped with the necessa- years under the Agreement of colla- – supervision of the correct functio- ry gear; boration: ning and compliance of signals for – ensure the surveillance and con- – enhancement of the ITN radar sea professionals on offshore faci- trol of these maritime areas and coastal network with electro-op- lities and installations; offshore facilities for security and tical systems, in areas where the – monitoring of possible hydrocar- safety purposes and environmen- ITN capacity for discovery is re- bon pollution, its extent and po- tal protection; duced and the offshore platform tential spilling from offshore faci- – hydro-oceanographic surveys and concentration is higher (i.e. nor- lities or from related activities. related activities for the construc- thern part of the Adriatic Sea); Over the years there has been a tion of suitable scale maps for – creation and implementation of progressive and significant increa- precise and detailed definition of a system for remote monitoring se in hours of patrol carried out as mining areas concessions; of the vessels carrying out explo- shown in Table 1. – professional development of staff ration activities in the Italian sea No significant assets or unautho- involved in the above activities. situation, through Smart Fenix, rized intrusions or pollution into off- Some of the service activities fall second version of a system initial- limits areas were detected. In addi-

12 Dicembre 2017 ambiente

Tab. 1. Navy patrol hours. rations using divers or ROV down to Ore di pattugliamento navale. a 1.500-meter depth. Task carried Year Patrol hours along the year Average hours of monthly patrols out by the helm divers of the Ope- 2014 114h 10m 28h 33m rative Divers Group (GOS), a special branch of the Divers and SEALs 2015 4077h 37m 331h 45m Grouping “Teseo Tesei” (COMSU- 2016 4738h 11m 394h 51m BIN). 2017 (August) 2225h31m 278h10m The GOS Divers perform the following tasks: – Damaged Submarine Castaways tion to: – monitoring of sea lines of the oil recovery. Using the ARS Anteo, – the issuing of a new series of special fields of Rospo Mare extended the Deep Diving Activity Sup- charts for mining purposes by the to the FPSO “Alba Marina” and port Ship belonging to COMSU- Italian Navy Hydrographic Office Vega offshore platform performed BIN can aid the crew of a subma- (http://iim.shopfactory.com/). by Mine Hunters ITS Viareggio rine which can no longer surface, – exchange of information inclu- and ITS Rimini: thanks to the high number of gear ding the limits of territorial wa- – visual inspection by remotely on board. Including the Mini- ters baselines and climatological operated vehicle ROV with video Submarine SRV 300 (able to and oceanographic information and/or photos of contacts; help 12 castaway per time), the by the Italian Navy Hydrographic – control of the sea line between McCann Rescue Bell, The Atmo- Office; the FSO (Floating Storage Offlo- spheric Diving System Suit, The – bottom survey using side scan so- ading) Leonis, storage vessel sup- Hyperbaric Facilities Built-In Sy- nar for about 80 km2 of areas exe- porting the Vega A platform, and stem for deep diving and the team cuted by ITS Aretusa in the Strait the platform itself; ROV’s. of Sicily; – or visual inspection by ROV (vi- – Disposal of any explosive device – support offshore activities inspec- deo and/or photos) of mud volca- found in maritime environment, tion of the Annamaria offshore noes. such as sea, rivers, lakes or floo- platform, thanks to the use of ITS ded places. But also on the surface Procida; such as on board ships or docks – water sampling from the purging and harbor, both ordnance or pipe of Brenda, Basil and Clara 3. The Operative Divers improvised. These activities are NW platforms by the Operative Group daily conducted by the member Divers Group of the Italian Navy of the EOD/IEDD Diving Te- Seals and Divers Command, Vari- The ITN is the only Italian ams (S.D.A.I) widespread in the gnano – La Spezia, and the rescue Armed Force with a Special De- country. In the only 2016 12.400 and divers vessel, ITS Anteo; partment able to perform diving ope- Explosive Ordnances and Devices

Fig. 1. GOS diver outboards from diving Chamber. Palombari del GOS in uscita dalla campana subacquea.

Dicembre 2017 13 environment

Fig. 2. GOS divers preparing to dive. Palombari del GOS in fase di preparazione all’immersione.

were found and disposed and from ples to check if there are leaks in the of the waters from the pipeline January to August of 2017 the pipelines are always available. that the DGS-UNMIG National number of those is 10.946 yet. Energy Resources Office reque- – Manifold Diving Operation, such sted, using the “Interspiro DP1” as any activities using the gear 3.2. Agreement fulfillment Surface Supplied Apparatus. abovementioned and for those – GOS actions for the DGS- tasks that make the GOS Divers UNMIG able to conduct surveys and re- coveries for the Archeological Due to the agreement and thanks 4. Italian Navy National Agencies, the Civil Pro- to the gear, the GOS conducted ope- Hydrographic Office tection Agency and, recently, for, rations on several offshore platforms the Ministry for the Economic in the Adriatic Sea. Development. The following actions were per- The Italian Navy Hydrographic formed using the proper apparatus: Office (IIM) is in charge of all the – Inspection of two ENI oil plat- official nautical documentation pu- 3.1. The propaedeutic forms, BASIL and BRENDA, blished in Italy. activities for the agreement 13 nm outside Pesaro. The GOS In order to produce updated and implementation Divers performed two dives of 30 accurate charts, IIM performs regular minutes from 9 to 19 meters to get surveys of the Italian coasts and seas As a result of surveys some offsho- samples of any fluid spilled from the – over 550,000 square kilometers of re oil platforms were chosen for the pipeline used for hydrocarbon pro- sea waters and more than 7,800 kilo- divers to perform their tasks diving duction activities. The operation meters of coastline – to collect data or by using their ROVs. To this end, was performed rapidly: the samples for nautical publications and charts, the MISE gave its support by pro- were given to the DGS-UNMIG both paper and electronic. These viding a dinghy, a Surface Support National Energy Resources Office. products, together with nautical in- Diving Apparatus to perform diving – CLARA NW Platform inspec- formation data diffused nationally until a 60 meters depth in polluted tion, 24 nm outside Ancona in and internationally, represent the waters, a “Sirio” ROV, for diving the Adriatic Sea, performed by official documentation required for until 300 meters and a manipulator ARS Anteo during its 2016 yearly the safety of navigation by national set for the “Perseo” ROV (alrea- campaign, the survey of a 12” sea and international standards. dy owned by the GOS), to perform line used to transport the gas were IIM has always played an acti- 1500-meter depth survey. performed July 5 using the ROV ve role in the study and in the pro- This fully deployable gear gave Sirio. The activity took place after tection of the sea, from a scientific, the Government the possibility to ENI provided the structure plans technological and environmental survey and test offshore facilities to avoid problems with the umbi- point of view, through projects carri- with the peculiar high safety stan- lical during the dives. The divers ed out with universities and research dard of the COMSUBIN Divers. also performed a 22-meter depth centers in Italy and abroad. Furthermore images and water sam- dive in order to get some samples Training is crucial for IIM, which

14 Dicembre 2017 ambiente

Both catamarans, they were de- and means. These means comprise signed to be used for hydro-ocea- Hydrographic Units and Experience nographic surveys in harbors, in Vessels, which complement the ca- shallow waters and at high sea. The pabilities of the Mine Countermea- main features of the Ninfe-class sure Units, by adding the special fe- units are high-maneuverability and atures provided by supplied sensors, accurate position keeping, guaran- which grant the highest precision teed by dynamic positioning (DP). standards, necessary to collect the A DP system automatically main- information support needed by Na- tains a vessel’s position and heading, val Hydrographic Institute for the which is essential during oceano- production of national nautical car- graphic surveys and depth sounding. tography. Fig. 3. The headquarters of the Navy The Aretusa and Galatea are further MARICODRAG, thanks to the Hydrographic Institute in Forte San Gior- gio (GE). equipped with a modern platform large portfolio of sensors and featu- La sede dell’Istituto idrografico della Marina automation system for the remote res granted by 10 Mine Counterme- in Forte San Giorgio (GE). control of the equipment on board asures Units, 3 Hydrographic Units, and with motor boats for surveys in 2 Marine Research Units, 2 last organizes specialization courses open shallow waters. generation Experience Vessels and to military and civilian students, in Autonomous Underwater Vehicles collaboration with the University (AUV), is capable to operate up to of Genoa. All courses by IIM are in 3000 meters conducting underwa- compliance with the relevant natio- 5. Mine Countermeasure ter research and investigation. In nal and international standards. and Hydro-oceanographic addition, the presence at the he- Forces Command adquarters of the Command of an Operational Center, called the Mine 4.1. The survey operation Warfare Data Center, dedicated to The task of countering the threat the collection of underwater infor- The Italian Navy Hydrographic posed by modern naval mines and of mation allows maintaining an up-to- Office operates three survey vessels – researching and clearing historical date maritime sea ground picture. Magnaghi, Aretusa and Galatea and explosive ordnances is carried out Thanks to these potentials, MA- a smaller specialized team. by the Mine Countermeasures and RICODRAG has a unique knowled- Magnaghi, the flagship, is the lar- Hydro-oceanographic Forces Com- ge of the sea, from the surface to the gest among the “white ships”, so cal- mand (MARICODRAG), with bottom, both nationally and inter- led because of their color, typical of the use of dedicated Naval Units nationally. The proof is that many those ITN units in charge of auxiliary services, such as search and training. Delivered to the ITN in 1975, the Magnaghi has been in service for 30 years. Equipped with state-of-the-art and regularly upgraded, the vessel is still used for hydro-oceanographic surveys, seafloor research, data collection and water column monitoring – also in research projects involving universities, National Research Centers, Ministry of the Environment and Ministry of Eco- nomic Development. The Magnaghi carries three fully equipped survey motor boats, ensuring simultaneous operation in more than one area. The other two Ninfe-class vessels – Aretusa and Galatea – were com- Fig. 4. The Navy’s hydro-oceanographic ships. missioned in 2002. Le Navi idro-oceanografiche della Marina Militare.

Dicembre 2017 15 environment

Fig. 5. Diving ROV operations. Operazioni per la messa a mare del veicolo subacqueo ROV. foreign Navies, National and Inter- line and the FSO ALBAMARI- lian Navy and the Ministry of Eco- national Organizations periodically NA Unit on the offshore ROSPO nomic Development has determined call on the capabilities of this “pole extraction field and the sea line what sailors; with their knowledge of excellence” to train their units or connecting PLEM (Pipe Line End and expertise perform daily at the take advantage of the expertise of Manifold) to ROSPO MARE B service of the community and the MARICODRAG platform; institutions. – Use of Hydro-Oceanographic Unit for Multi-beam Echo sounder 5.1. Main activities (MBES) mapping of an area within the VEGA Extraction Field. Lista degli acronimi Following the agreement, MA- RICODRAG supported the DGS- MM – Marina Militare UNMIG for the conduct of inspec- MISE – Ministero dello Sviluppo Eco- tions to check off-shore platforms 6. Conclusions nomico and related sea lines: DGS-UNMIG – Direzione Generale – use of Mine Countermeasures Cooperation between the MISE per la Sicurezza anche ambientale Units for the conduct of Sonar DGS-UNMIG and ITN is essential delle attività minerarie ed energe- searches and ROV investigations, to the effectiveness and impact of tiche Ufficio Nazionale Minerario with acquisition of video-photo- the action of the State in marine en- per gli Idrocarburi e le Georisorse graphic material of contacts of in- vironments. CINCNAV – Comando in Capo del- terest, reported by DGS-UNMIG Optimization of available rela Squadra Navale close to VEGA offshore field, par- sources, employing the most quali- CaSMM – Capo di Stato Maggiore ticularly near the VEGA platform fied and fine structures of the ITN in della Marina Militare ALFA and the connecting pipe- their specific expertise is beneficial FA – Forza Armata lines between that platform and to society. GOS – Palombari del Gruppo Ope- the FSO LEONIS, as well as the This methodology of work, which rativo Subacquei inspection of some mud volcano- was endorsed by the Italian Navy for COMSUBIN – Raggruppamento Su- es located near these pipelines; many years, saw the CINCNAV’s bacquei ed Incursori – the use of Mine Countermeasures ships, GOS/COMSUBIN’s divers, SDAI – Sminamento Difesa Anti Units for the conduct of Sonar IIM’s Hydrographers, MARICO- mezzi Insidiosi searches and ROV investigations DRAG’s navies and sailors used in ROV – Remotely Operated Vehicle with the acquisition of video- many complex activities within the IIM – Istituto Idrografico della Marina photographic material of the link framework of their tasks. MARICODRAG – Comando delle infrastructure between the sea The agreement between the Ita- Forze di Contromisure Mine

16 Dicembre 2017 ambiente

The Italian Coast Guard for M.S. Mazzarese* * Comando Generale del Corpo delle the offshore safety Capitanerie di porto – Ufficiale di collegamento

The prospection, exploration and production of hydrocarbons at sea, in many aspects and effects, affect most of the Italian Coast Guard functions, in particular the protection of the marine environ- 1. The Italian Coast Guard ment and coastal areas, maritime safety, maritime police and ship traffic control, making it a faithful synthesis and enhancing the role of the Maritime Authority. and the partnership with This is a sector in which the Italian coast Guard and the current DGS-UNMIG have always worked DGS-UNMIG together, with an integrated approach to the management of marine areas of economic and production interest that has translated into synergies of exercise in daily operations. Mining activities at sea, in their The long-standing functional relationships between the Maritime Authorities and the UNMIG Sec- various implications, engage the Ita- tions have finally found further sanction and implementation at a central level with the Memoran- dum of Understanding of 16 September 2014, to achieve a combined and shared management of lian Coast Guard in the main powers offshore realities, harmonizing the procedures and linking the actions of their own competence to and under the exclusive responsibi- ultimately ensure the full safety, even environmental, of plant operations. lity for environmental, maritime sa- Within the framework of the offshore security network woven by DGS-UNMIG, in addition to its fety and navigation, maritime police know-how, the Italian Coast Guard has made available its territorial structure, divided into 295 mar- and traffic control. itime offices distributed along the national coasts and its equipment (aircraft and vessels) of utmost Under the auspices of the Mini- readiness and effectiveness, together with highly specialized personnel and availability. stry of Infrastructures and Transport The resources used for the environmental monitoring of mining areas at sea are aircrafts and ves- and its main institutional tasks, the sels (with discovery, location, classifications, identification and tracking capability), the Divers Unit (to Italian Coast Guard operates under inspections of wellheads, underwater pipelines and supporting structures of the platforms) and the a functional dependence on the Mi- LAM – Mobile Environmental Laboratory (for sea water sampling and analysis). nistry of Environment and the Mini- The activities carried out, in accordance with appropriate guidelines for intensifying the surveillance stry of Agriculture, Food and Forest- of the marine areas affected by offshore platforms and structured on the optimization of resources, have so far been fully satisfied with the aim of preventing possible pollution and offences, emblem- ry. These Ministries use the structure atically expressed by the small number of detected violations, all due to accidental overruns in and professional skills of the Italian security zones. Coast Guard as their own technical The challenge for the future is to focus on a growing diffusion of interventions and the specialization articulation for the related profiles of operational arrangements, by developing fine forms of collaboration to confirm shared and rein- of marine protection, fisheries and forced institutional trust. environmental protection, in terms Keywords: Italian Coast Guard, MISE / DGS-UNMIG, offshore safety, environment, maritime. of prevention, intervention and coordination for pollution control. La Guardia Costiera per la sicurezza offshore. Le attività di prospezione, ricerca e coltiva- Its 295 maritime offices along the zione degli idrocarburi in mare, nei suoi molteplici aspetti ed effetti, interessano gran parte delle fun- coastline, the availability of air and zioni del Corpo delle Capitanerie di porto – Guardia Costiera, quali la tutela dell’ambiente marino e naval assets with immediate opera- costiero, la sicurezza della navigazione e del trasporto marittimo, la polizia marittima ed il controllo del traffico navale, costituendone fedele sintesi e valorizzandone il ruolo dell’Autorità marittima. tional readiness and the specialized Trattasi di un settore in cui il Corpo e l’attuale DGS-UNMIG hanno da sempre lavorato congiunta- staff of proven versatility make it a mente, con un approccio integrato alla gestione delle aree marine di interesse economico e produt- widespread, flexible and streamli- tivo che si è tradotto in sinergie di esercizio nella quotidiana operatività. ned organization that is constantly Le relazioni funzionali da tempo intrattenute localmente tra le Autorità marittime e gli UNMIG oriented to user needs. hanno trovato, da ultimo, ulteriore sanzione ed implementazione a livello centrale con la stipula These features enabled, within il 16 settembre 2014 del Protocollo d’intesa, attraverso cui realizzare una gestione combinata e the partnership with DGS-UNMIG condivisa delle realtà offshore, armonizzandone le procedure e raccordandone le azioni di rispet- under the Memorandum of Under- tiva competenza, al fine ultimo di garantire la piena sicurezza, anche ambientale, delle operazioni standing signed on 16 September d’impianto. 2014, to promote and support useful Nell’ambito del network della sicurezza offshore intessuto dalla DGS-UNMIG, il Corpo ha messo a and effective cooperation between disposizione, oltre al proprio know-how, la sua struttura territoriale articolata in 295 uffici marittimi the territorial units (respectively, distribuiti lungo le coste nazionali e le sue dotazioni strumentali dall’impiego operativo di assoluta prontezza ed efficacia, unitamente a personale di alta specializzazione e reperibilità. UNMIG Sections and local Coast Le risorse impiegate per il monitoraggio ambientale delle zone minerarie a mare vanno dai mezzi Guard Offices) for optimizing and aerei e navali (dotati di sistemi di scoperta a lungo raggio, localizzazione, classificazione, identifica- simplifying the competence activi- zione e tracciamento di inquinamenti di idrocarburi e di altre sostanze oleose in mare) ai Nuclei Su- ties aimed at increasing the protec- bacquei (per le ispezioni visive alle teste di pozzo, alle condotte sottomarine e alle strutture portanti tion of primary goods involved as:

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 17-23 17 environment degli impianti) ed alla componente specialistica LAM – Laboratorio Ambientale Mobile (per attività resources (human and material) in di campionamento ed analisi). support of DGS-UNMIG to achieve Le attività condotte, secondo apposite linee guide finalizzate ad intensificare la vigilanza delle aree marine d’impianto e strutturate sull’ottimizzazione delle risorse, hanno sinora raccolto pieno soddi- this joint plan. sfazione soprattutto ai fini di prevenire possibili inquinamenti ed illeciti, emblematicamente espresso dall’esiguo numero di contestazioni elevate e tutte riconducibili a sconfinamenti accidentali nelle zone di sicurezza. La sfida per il futuro è di puntare verso una sempre maggiore diffusione degli interventi e specia- 2. Activities lizzazione degli assetti operativi, sviluppando affinate forme di collaborazione a conferma di una fiducia istituzionale condivisa quanto rafforzata. As a result of the partnership be- Parole chiave: Guardia Costiera, MISE / DGS-UNMIG, sicurezza offshore, ambiente, marittimo. gun under the Memorandum of Un- derstanding of 2014, in recent years the Coast Guard has played an im- protecting the safety of industrial rine accidents”) and the Decree of portant supervision and monitoring operations, health, navigation and the Ministry of Environment No role of marine areas where offshore maritime transport, environment 34 dated 29 January 2013 (“Opera- platforms are present through the and coastal communities. tional plan for emergency response use of air and naval assets, according The primary aim is to prevent to protect the sea and coastal areas to an operational program and the possible accidents, but also to en- from accidental oil pollution and following criteria: sure an immediate and qualified re- other harmful substances”); – concentration of offshore plat- sponse to any emergency in order – the identification and/or revision forms to counter, mitigate and eliminate of the so called “Safety zones” – distance from the coast harmful effects. around the platforms – establi- – analysis of traffic flows in the area Particularly important for this shed by specific ordinance of the – analysis of the anthropogenic im- purpose is: Maritime Authority – together pact of the affected areas – the supervision and control of of- with the verification of com- The operational commitment, fshore installations, through joint pliance with the relevant safety especially towards the prevention, inspections and visits of their re- requirements for navigation and assured the coverage of the entire spective interests; monitoring of exploration and national offshore area, while achie- – the emergency planning of instal- research vessels, including the ving a higher rate of control along lations is consistent with S.A.R. use of the VTMIS system (Vessel the Ionian and Adriatic coasts whe- (Search and Rescue) local plans Traffic Monitoring and Informa- re there is a considerable concentra- and the local pollution plans tion System) for maritime traffic tion of offshore platforms. drafted by the responsible Mari- carried out and managed by the time Authorities; in this way the Coast Guard Headquarters as the intervention procedures and the National Competent Authority; counter and mitigation actions to – the exchange of information safeguarding human life and envi- between the two administrations ronmental safety are optimized; including the involvement of – the exchange of information concession companies staff that between the UNMIG and the Co- manage the offshore platforms as ast Guard Headquarters, in order well as the other institutional enti- to perform the operational and ties concerned, in various respects, tactical direction of the aircraft in the mining activities security, used in the antipollution activi- including environmental, thus ties in case of accidental spills of delineating jointly operating pro- hydrocarbons and other harmful cedures related to the type of in- substances; these activities must tervention and supported by more follow the normative provisions and more innovative instrumenta- of Law No 979 dated 31 Decem- tion; ber 1982, in the Prime Ministe- – the support of staff training to in- rial Decree dated 4 November crease the technical knowledge, 2010 (“National emergency pre- generally aimed at preventing fire Fig. 1. Operations Center: maritime traffic paredness plan for the protec- and accidents. control. tion from oil pollution and other The Italian Coast Guard has Centrale operativa: controllo del traffico ma- harmful substances caused by ma- made available its experience and rittimo.

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In 2015, a total of 1131 hours of to improve the flow of information ra able to hook up a small target patrolling was carried out for offsho- in case of anomalies found during (2.3 x 2.3 meters) at a distance of re safety: in particular 861 hours of naval patrol. 5 miles (with a 2 miles recogni- naval patrol for 7439 miles traveled tion and 1.5 miles identification) and 270 hours of air patrol. and to locate polluting wastewa- During naval missions, particular ter with filming to accentuate the attention was given to the monito- 3. Resources thermal differences. ring of maritime traffic, the verifica- Thanks to a gyro-stabilized plat- tion of maritime signaling systems The Coast Guard exerts – through form with 360° rotation for con- and the compliance with the orders its Operations Center, the periphe- tinuous flotation, EOST provides issued by the relevant Maritime Au- ral commands and the specialized re- extremely stable images even in the thorities for the purpose of safety na- sources (naval and air assets, Divers presence of high turn rates and with vigation in particular the applicable Unit and Environmental Laboratory the pushing optic to maximum focal interdiction measures in the safety Mobile) the services related to the lengths. zones over a distance of 500 meters actions for fighting marine pollu- The Side Looking Airborne Ra- around the platforms – with the aid tion. This system is integrated by a dar (SLAR), however, is a primary of optical recognition methods, AIS satellite surveillance service, as part radar sensor active for the long- (Automatic Identification System) of a specific collaboration with the range detection of hydrocarbon and and radio (via VHF queries). European Maritime Safety Agency other oily substances at sea up to 80 All aerial surveys were conducted (EMSA). miles (40 miles for each side of the with the use of remote sensing of en- aircraft) in feature function, ensu- vironmental systems (vision infrared ring good performance in any mete- and SLAR) for a prompt identifica- 3.1. Aircrafts orological condition. During over- tion of any, even minimal, spillage. flow, the sea surface is radiated at a Coast Guard staff, in the exercise For the environmental moni- distance of 20 or 40 miles from the of its judicial police duties, detected toring of areas affected by offshore waves emitted by the two antennas and notified offenders of a few in- installations, significant use was placed on the sides of the fuselage; fringements for encroachment in made of the ATR 42 MP (Maritime since the presence of oily substances the safety zones; the low number of Patrol), a twin-engine turboprop for (hydrocarbons) result in a reduction detected violations (a total of 18 in wide and medium-range maritime in the wave crests, a different respon- 2015) is the positive result of the pa- patrols and with discovery, location, se (return echo) will occur in the af- trol by air and naval means, making classification, identification and tra- fected parts of the spills that will be it an effective deterrent to the com- cking capability. displayed on the on-board monitor. mission of any offence. The aircraft is characterized by The cross-check between the SLAR In the activities, performed under a Maritime Patrol Mission System positive response, the IR camera the agreement signed between DGS (MPMS) which, through three and the visual inspection made by UNMIG and the Coast Guard, there MOC (Multi-Function Operating the crew allows to discriminate the is also the observation of the systems Consoles) managed by flight ope- presence of hydrocarbons from other for the detection and management rators, allows images displayed by natural phenomena (false echoes), of any anomalies and the inspection high-resolution monitors relayed by such as currents or “Wind jumps”. of sea-lines and submerged structu- search sensors. The aircraft also has an ATM EN- res. In particular, the EOST (Electro HANCED multiband spectroscopy Significant boost was given in the Optical Surveillance and Tracking) able to capture digital images of the course of 2016 to the joint inspec- sensor enables detecting and reco- sea surface in spectral bands ranging tions carried out by Coast Guard gnizing – even at night – pollution from invisible to thermal infrared personnel and UNMIG staff, with and craft through the following de- light. Specific software is used to particular attention paid to offsho- vices: process, theme maps of fundamental re platforms where gas is produced, – High resolution ATV (Acquisi- macro-descriptor parameters of sea where sea water samples were taken tion TV) color camera; health such as suspended solids, or- by the Divers Unit and the support – LRTV (Long Range TV) long- ganic matter, chlorophyll, and tem- of the new offshore patrol boats CP range video camera, able to di- perature distribution are made. 328. stinguish marks (20 cm in size) on Lastly, the Daedalus 1268 ATM Finally, there is a project betwe- the sides of ships at a distance of Enhanced Multispectral Passive en the Operations Center, DGS- 1.5 miles; Sensor allows to carry out, by its 12 UNMIG and the UNMIG Sections – High resolution infrared IR came- channels divided into 11 spectral

Dicembre 2017 19 environment bands (of visible and infrared elec- images to be sent to the STAI (the stations that provide radio coverage tromagnetic radiation), surveys of national remote sensing service) at of the entire coastal profile exten- various environmental parameters the Italian Coast Guard Headquar- ding deeply to the entire SAR area useful to elaborate a general pictu- ters for processing and interpreta- (Search and Rescue) of Italian com- re on the marine and coastal ecosy- tion. petence. The information obtained stems status. Through this remote is centralized and integrated with sensing system, a thematic carto- those from the MARES (Mediter- graphy of narrow marine areas is pro- 3.2. Vessels ranean AIS Regional Exchange Sy- duced providing indications on the stem) system, LRIT (Long Range In- distribution of a particular sought The Coast Guard has currently formation and Tracking), NAVTEX substance such as hydrocarbons; and nearly 600 vessels (including naval and Naval Reporting (mandatory in thanks to the properties of each ma- units and minor assets) located in the Adriatic) ADRIREP; the same terial to reflect electromagnetic ra- 113 national ports. information made available to other diation in the light of the incident The naval component is consi- State Administrations through ap- light, offering its own spectral form stently employed in patrol opera- propriate machine-machine interfa- that is captured by the Daedalus tions, mainly through offshore ves- ces. 1268 apparatus. sels with large autonomy Class 200 Among the naval vessels invol- EOST, SLAR and Daedalus 1268 located in ports near offshore plants ved in the surveillance and control sensors are managed by the Airbor- (Ravenna, Ancona, Pescara, Bari, activities, a special mention must ne Tactical Observation and Sur- Reggio Calabria, Palermo and Cata- be made of the CP 328 propulsion veillance (ATOS) system, a highly nia). unit, normally dedicated to rese- technological platform that provides In particular, as part of the AIS arch and rescue aid that has been a complete and immediate interac- system, a complex national net- suitably equipped with a mobile lation between multiple sensors and work created by the Coast Guard boratory for analysis on water and subsystems. The data obtained are Headquarters as a National Compe- air components related to the in- available to the operator in real time tent Authority – was used to control troduction of aqueous effluents and on the multifunction display and marine traffic, to receive ship-to-air gas emissions into the atmosphere. can be recorded and processed into information, articulated on 63 base Rugged and self-supporting, with

Fig. 2. ATR 42 MP & SLAR. ATR 42 MP e SLAR.

20 Dicembre 2017 ambiente a capacity to operate in bargain of about 6.500 miles, these units are ry role and level, allows the Italian marine weather conditions, it has able to carry out their missions of Coast Guard to have independent recently been equipped with a Se- antipollution with oil recovery ca- capabilities (based upon concrete re- aGuardian EOSS-7a Surveillance pacity (500 cubic meters), supplied sults) to fulfill, in a multifunctional Sensor System, characterized by with 250 meters of high sea floating dimension, its own judicial police high technological content with barriers and skimmer, ability of deck tasks, the protection of the marine daytime and mid-range night vision landing and refueling for helicopters environment, the fishery resources capabilities. In addition, the unit AB 412/AW 139 and abilities to use and underwater archaeological as- has a dedicated crane for landing Divers Unit. sets, plus the latest interventions in the functional instrumentation to case of flood events and the mission determine the chemical/physical of safeguarding human life at sea in parameters and the sampling of the 3.3. Divers Unit the context of emergency migrants water column. through the rescue swimmer compo- For its features and for its exclu- Divers, who undergo a specific nent. sive operational use, it is another four-year training program, make up The specific use for offshore safety instrument that assures an even gre- other highly specialized resources. is achieved by visual inspections of ater environmental safety of marine There are five units located throu- wellheads, underwater pipelines and research and facilities. ghout the country, specifically in supporting structures of the plants Particular vessels dedicated to an- San Benedetto del Tronto, Naples, in order to verify their integrity and tipollution activities and protection Messina, Cagliari and Genoa. to ensure that no alterations can be of the marine environment are the Since the establishment of the made to correct their functionality. patrol boats Class Dattilo: with their 1st Divers Unit as an Experimen- The diving operations are con- large size dimensions (94 meters), tal Department in 1995 and its full ducted with the aid of self-contained full load displacement (of about operation and formal recognition in breathing apparatus to a depth of 3.600 tons, equal to a large Corvet- 1996, the underwater component, 40 meters, in addition to the ROV te or a light Frigate), an autonomy with its current 57 operators for eve- (Remotely operated underwater

Fig. 3.Patrol boats class 200 & class 300. Motovedette d’altura veloce classe 200 e classe 300.

Fig. 4. Antipollution exercise. Esercitazione antinquinamento.

Dicembre 2017 21 environment vehicle) capable of maneuvering Decree 152/2006 and as an enhance- ry located at the maritime office of several hundred meters below the ment of the operational capacities, Rome (Fiumicino) to support mo- sea surface and recording the images the Italian Coast Guard has been nitoring activities in environmental with depth data, cardinal orienta- equipped with the LAM (Mobile prevention and the fight against en- tion and temperature data, as well as Environmental Laboratory) with vironmental crimes. searching for distant and not visible biologists and lab technicians. objects by sonar. Coordinated by the Italian Co- In order to implement the exi- ast Guard Headquarters and upon sting inter-institutional framework, a request of the local maritime offices 4. Conclusions series of joint inspections were carri- (which support the investigative ac- ed out with DGS-UNMIG technical tivity), LAM staff intervenes on site The collaboration started – for staff sampling water at gas extraction to carry out sampling and analysis of shared activities and purposes – with platforms (in particular, downstream the reported environmental critica- the Memorandum of Understanding of the treatment plant with activa- lity. During missions, special vehi- and specifically aimed at the safety, ted carbon filter and the base of the cles, equipped for chemical-physical including the environmental safe- dead casing for drainage of the layer and microbiological analysis in ac- ty, of the research and exploitation waters) for the subsequent analysis cordance with current procedures, plants at sea, has so far delivered by the laboratories of the Directo- are used so as to provide an imme- good results, leading to intensifica- rate General and the verification of diate response in emergency situation of controls and a greater aware- compliance with the law. tions. ness of the offshore industry. Given the recognized effective- The already substantial number ness of this component as a tool to of aeronautical patrol hours asso- 3.4. Mobile Environmental counter marine and coastal pollu- ciated with the small number of de- Laboratory tion, there is a project with DGS- tected infringements demonstrates UNMIG that involves the acquisi- how ensuring a constant presence In order to carry out its institutio- tion of a dedicated land mobile lab. in the areas of interest is effective nal tasks in the field of environmen- Recently, the Corps also has an in itself, first of all for the sake of tal protection under Legislative Environmental Analysis Laborato- deterrence.

Fig. 5. Underwater operation to platform. Operazioni subacquee alle piattaforme.

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Fig. 6. LAM: sea water sampling and analysis. LAM: campionamento ed analisi di acque marine.

Operational use must tend to increasingly optimize the resources and specialization of the facilities, both in terms of means and personnel, looking at offshore security in a prevention perspective, coupled with the certainty of providing any more valid and fast response emergency intervention. In order to ensure the safeguarding of common goods such as the health of the environment, human health and safety of maritime transport, a decisive role has been at- tributed to the sharing of mature professionalism and the baggage of experience which is, in itself, an instrument of an increase in the safety gradient of the offshore mining acti- Fig. 7. Emergency demonstration: POLLEX 2017 Exercise on board the Garibaldi C vities of our seas. platform. The existing agreement, in parti- Esercitazione marittima complessa antinquinamento: POLLEX 2017 Operazioni presso la cular, is in line with the most current piattaforma Garibaldi C. governmental guidelines to counter duplication and redundancy, stre- mentary functions and putting the Future projects can only be found amline and simplify the processes of support activities as a tangible sign in this goad to action, in the per- the Public Administration, realizing of mutual institutional trust reinfor- spective of even greater efficiency in the mutual enhancement of comple- ced over time. the name of offshore security.

Dicembre 2017 23 ambiente

M. Simeone* Green House Gas Emissions A. Basco** A. Criscuolo** from oil and natural gas P. Salatino* production * Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Napoli, Italy ** Amra Scarl, Analisi e Monitoraggio The No Risk No Energy (NRNE) project, supported by the Italian Ministry of Economic Develop- del Rischio Ambientale, Napoli, Italy ment – Directorate General for Safety, intends to develop a quantitative methodology to assess environmental, economic and social impacts deriving from the exploitation of energy resources by taking into account geographical and social peculiarities of the exploitation site. In this paper, we specify the models used to estimate greenhouse gas emissions from oil and gas operations and we present their application to fictitious fields approximating real Italian oil and gas fields. order to support our leaders in the We identified OPGEE as the ideal model to estimate greenhouse gas emissions from oil operations complex choice between competi- and we implemented a model based on NETL libraries to estimate emissions from natural gas tive alternatives, the models applied production. Model boundaries are Well to Refinery Gate for oil and Well to Tank for natural gas. within the NRNE project must take Sensitivity to selected input parameters is also presented. into account the geographical and Keywords: emissions, greenhouse gas, oil, gas, OPGEE. social conditions of the specific sites where the energy exploitation facili- Valutazione delle emissioni di gas serra derivanti dalla produzione di petrolio e gas ties will be located. naturale. Il progetto NO RISK NO ENERGY è finanziato dal Ministero dello Sviluppo Economico, In this paper, we describe the mo- Direzione Generale per la Sicurezza anche ambientale delle attività minerarie ed energetiche, ed ha come obiettivo la messa a punto di una metodologia quantitativa per la valutazione degli impatti dels identified to quantify the green- ambientali, economici e sociali connessi con varie filiere energetiche nelle diverse aree geografiche house gas emissions deriving from oil italiane. In questo lavoro si presentano le metodiche individuate per la valutazione delle emissioni di and gas production, which represent gas serra derivanti dalla produzione di petrolio e gas naturale. I modelli selezionati contengono i det- a starting point towards the final tagli al livello di processo e permettono la contestualizzazione dei risultati alle specifiche tecnologie goal of the NRNE project. utilizzate e alle specifiche caratteristiche dei giacimenti considerati. Greenhouse gas (GHG) emis- Per la produzione di petrolio si è scelto di utilizzare l’OPGEE – Oil Production Greenhouse gas sions deriving from production, Emissions Estimator – che include le emissioni relative a tutte le operazioni della filiera del petrolio, processing, and transport of crude dalla esplorazione, alla produzione, fino al trasporto del greggio prima della raffinazione (approccio petroleum vary significantly with Well to Refinery Gate). production practices and crude oil Per la produzione di gas naturale è stato, invece, realizzato un modello a partire dalle librerie pubbli- quality, as well as with the location cate dal National Energy Technology Laboratory (NETL). Tale modello permette l’analisi dettagliata of the production site. Similarly, al- delle emissioni delle fasi che vanno dalla perforazione fino allo stoccaggio prima dell’utilizzo finale (approccio Well to Tank). though natural gas is a cleaner bur- I modelli sono stati applicati a campi fittizi con caratteristiche che approssimano quelle dei giaci- ning and more flexible fuel than oil, menti italiani. its primary component, methane, is I risultati presentati riguardano le emissioni per ciascuna fase del processo e l’analisi di sensitività a powerful greenhouse gas — 8 to dei risultati alle variabili di input più significative. 72 times as potent as carbon dioxi- Parole chiave: gas serra, petrolio, gas naturale, emissioni, OPGEE. de (CO2) (Forster et al., 2007), and emissions of methane during the extraction, transmission, and delivery of natural gas contributes significan- 1. Introduction without any risk for people, animals tly to total greenhouse gas emissions and the environment because the of the process. Methane losses as Maintaining and hopefully im- exploitation of any energy source well as other emissions depend on proving our life standards requires has both positive and negative im- the source of natural gas, on the ge- stable and abundant energy sup- pacts. This is the guiding principle ographic location of the formation ply. Energy can be produced form a of the project No Risk No Energy and, of course, on the technology variety of primary sources, such as (NRNE), whose goal is to develop adopted to extract the gas. petroleum, natural gas, photovol- a quantitative tool to calculate the There are several mathematical taic, wind, biomass and geothermal. environmental, economic and social models available in the literature to Unfortunately, it is not possible to impacts deriving from the exploita- estimate the emission of oil and gas imagine ways of producing energy tion of different energy sources. In production (Vafi .K., and Brandt

24 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 ambiente

AR. 2014) differing in scope and in versity (El-Houjeiri et al. 2012, 2013, values to compute emissions even if the level of detail. Starting with the 2015a, and 2015b). It calculates the input data are incomplete. The in- most broad, they can all be classified energy use and emissions from cru- put data are classified in categories, in four main categories: (1) general de oil production using engineering as it follows: LCA models utilizing sector-specific fundamentals of petroleum produc- – Production methods, such as economic input output modeling to tion and processing and allows to downhole pump, water reinjec- compute emissions due to producing flexibly estimate emissions from a tion, gas reinjection, water floo- a good or service (e.g. EIO-LCA mo- variety of oil production emissions ding, gas lifting, gas flooding, and del); (2) general LCA models using sources by using Microsoft Excel. steam flooding. The selection of a process-based approach to model OPGEE estimates emissions from the production method depends activities in all economic sectors sta- the well-to-refinery-entrance gate on the difficulty in pumping up of ting form data bases of environmen- (WTR boundary), thus including the oil. tal fluxes from production of goods emissions from all production opera- – Field properties, such as field age, and services (e.g. GEMIS, EcoIn- tions required to produce and tran- field depth, oil production volu- vent, Gabi); (3) transportation fuel sport crude oil to the refinery gate. me, number of producing wells, cycle LCA models, often called Well The process is broken down in the well diameter, productivity index to Wheel (e.g. GREET, GHGenius, following stages: (i) Exploration, i.e. and average reservoir pressure. JRC WTW); (4) crude-oil and gas actions to search and characterize – Fluid properties, such as API gra- specific engineering-based models, the petroleum field. (ii) Drilling and vity of crude oil, which characte- which perform detailed calculations development, i.e. field development rize the crude oil as “heavy” or of the petroleum and gas production and construction. (iii) Production “light” and composition of produ- process and leverage existing LCA and extraction, i.e. operations requi- ced associated gas. tools (such as the GREET model) red to lift fluids from the subsurface – Production practices, which in- to perform life cycle computations and to inject fluids into the subsurfa- clude gas-to-oil ratio (GOR), (e.g. Jacob Consultancy, OPGEE and ce. OPGEE includes downhole pum- water-to-oil ratio (WOR), water- NETL libraries). These models, by ps (e.g., sucker-rod pumps) as well as injection ratio, gas lifting injec- reaching process-level detail, are able the injection energy requirements of tion ratio, gas flooding injection to provide site-specific results and water flooding, gas flooding, and ste- ratio, steam to-oil ratio (SOR), are, therefore, the ideal candidates am flooding. (iv) Surface processing, fraction of required electricity ge- for the scope of the NRNE project. i.e. handling of crude oil, water, and nerated on site, fraction of remai- For their transparency, diffusion associated gas. This includes water− ning gas reinjected, fraction of and free availability we selected oil separation, gas−oil separation, water produced reinjected, frac- OPGEE to describe greenhouse gas crude stabilization, gas processing, tion of steam generation via co- emissions deriving from crude oil and water treatment. (v) Maintenan- generation and volume fraction production and the libraries provided ce, i.e. venting and fugitive emissions of diluent. The information about by NETL to describe the emissions associated with maintenance (e.g., the production practices correlate deriving from natural gas production. compressor blowdowns, well worko- with these of the production me- The models have been applied vers and cleanups). (vi) Waste di- thods and have significant role in to a small set of fictitious fields as sposal, i.e. emissions associated with the resulting emissions. an approximation of real Italian oil waste disposal. (vii) Crude transport, – Processing practices, such as the and natural gas fields. Results report i.e. transport of crude oil from the use of heater/treaters, stabilizer emission breakdown throughout the production site to the refinery gate. columns and gas processing units process and sensitivity analysis to The functional unit of OPGEE is (AGR, dehydrator and deme- the most relevant input parameters. 1 MJ of crude petroleum delivered thanizer), the ratio of gas flared to the refinery entrance. Emissions to oil produced, and the ratio of are represented as gCO2 equivalent gas vented to oil produced. Ac- per MJ of crude at the refinery gate. cording to the quality of produ- 2. Methods This functional unit is held constant ced oil mixture, certain treating throughout the model and the ener- processes are applied for further 2.1. OPGEE gy content of crude oil at the refinery treatment of gas, oil and water in- gate is calculated based on API gra- cluded in the oil mixture. The Oil Production Greenhouse vity. – Land use impacts, which include gas Emissions Estimator (OPGEE) is Although a significant number of ecosystem carbon richness and re- an engineering-based, open-source input data is required to describe the lative disturbance intensity. This model developed at Stanford Uni- process, OPGEE uses “smart” default parameter relates to the additio-

Dicembre 2017 25 environment

nal emissions of the wider oil field tor and a PM factor. In this paper, seen, the user will have to inclu- due to the disturbance of land du- we refer only to Greenhouse Gas de: the composition of natural gas ring the drilling and production (GHG) emissions, represented as processed, which corresponds to processes. gCO2 equivalent per MJ of Natural the composition of the natural gas – Crude oil transport, which deter- Gas delivered to the end user, thus transported, the efficiency of the mine transport modes and distan- following a Well to Tank approach. amine regeneration plant, the type ces. Crude oil transport covers the The model implemented breaks of dehydration plant, the type of tracks (marine or by road) from down the process in the following compressor used. the oil well to the European refi- stages: i) drilling and wells comple- – Transport data: The user is asked neries gates. tion, ii) extraction, ii) surface pro- to include: the type of transport, All required inputs to OPGEE cesses and iv) transportation. choosing between pipeline and are assigned default values that can The interaction with the user methane tanker, the distance tra- be kept as they are, or changed to occurs through three worksheets, as veled, the payload. The choice of match or changed to match the cha- described below: the type of transport is carried out racteristics of a given oil field or oil Input worksheet: In this section, only when the field is offshore, be- quality. If only a limited amount of the user introduces the parameters cause for on-shore field, transport information is available for a given to characterize the field. This work is always considered in pipelines. facility, most input values will re- sheet, in turn, is divided in five sec- Emissions analysis worksheet: main equal to defaults. Otherwise, tions, as it follows: The emission analysis section is if detailed field-level data are availa- – Field data: In this section, the where the emission calculations are ble, a more accurate emissions esti- user introduces the details of the performed. Emissions compute ven- mate can be generated. field, such as: name of the field, ting emissions, flaring emissions and For some processes and sub-pro- expected lifetime, type of field emissions from combustion of the cesses, defaults rely on correlations (onshore or offshore), average fuel required for operations and to and relationships with other para- depth of wells, total number of run the auxiliaries. The process is meters. For example, the amount perforated wells, number of pro- broken down in stages, as it follows: of water produced with oil (water- duction wells, type of extraction – Drilling and completion of wells: oil ratio or WOR) affects the ener- (i.e. whether or not it is an asso- In this stage, emissions are gene- gy consumed in lifting, handling, ciated extraction of gas and oil), rated by the use of the drilling and separating fluids. If WOR is production volumes and composi- rig, and by venting episodes oc- unknown, OPGEE includes a stati- tion of natural gas extracted. curring during drilling and well stical relationship for water produc- – Drill and well completion data: completion. These emissions are tion as a function of reservoir age. This section includes information limited to a very small period of about the technologies used in the time compared to the average life drilling and completion phase, of the field. 2.2. Model developed from such as: drilling method, drilling – Extraction: In this stage, the NETL libraries direction (vertical or horizontal) emissions are derived from flaring, efficiency of the drilling rig. i.e. by the gas sent to and burned To model emissions form Natu- – Extraction data: This section in- into the torch, and from venting, ral gas production, we developed cludes information on the natural generated by ordinary extraction a tool in Excel starting from the li- gas extraction phase. In particu- operations but also by liquid unlo- braries published by National Ener- lar, the user is required to enter ading and workover episodes. gy Technology Laboratory (NETL). the daily average amount of gas – Processing: In this stage, emissions The libraries analyze the emissions delivered to the torch and the fre- are generated by surface processes of the different stages of the Natu- quency of workover episodes (in- and by the use of compressors. ral Gas production process, inclu- vasive maintenance episodes). Specifically, there are emissions ding gas transport to large end users. – Surface processes data: This sec- from venting and emissions gene- Emission inventories published by tion includes information on sur- rated by the use of natural gas to NETL refer to the 2010 average na- face processes such as dehydration, power the various plants. tural gas production in US and were softening and compression. The – Transport: Emissions from this scaled down to the Italian Natural first two treatments are not always phase are related to the diffe- Gas production. The libraries allow provided since the extracted na- rent modes of transport and are calculation of a Greenhouse gas fac- tural gas may be anhydrous and / emissions of venting and emis- tor (GHG factor), an Acidification or free from sulfuric acid. In the sions from fuel combustion. The factor, a Photochemical oxidant fac- event that all treatments are fore- modes of transport considered in

26 Dicembre 2017 ambiente

this model are two: pipeline and 3. Results Tab. 1. Key parameters for each field. methane carriers (LNG carrier). Parametri di input per ogni campo. Transportation from offshore 3.1. Greenhouse Emissions Field API Field WOR fields is always considered throu- from Oil production gravity depth [ft] [bbl water/bbl oil] gh methane carriers. Results worksheet. In this section, For running OPGEE and explo- 1 18.6 7,000 4 the user reads the results obtained ring the model sensitivity to selected 2 15.5 19,000 30 from the analysis. A flow chart re- input parameters, we defined four ports details of the analyzed field and fictional fields. Two of these (Field 1 3 19 1,500 2 the percentages of the processed, and Field 2) are an approximation of 4 30 4,000 10 transported and delivered gas. real Italian oil fields, whereas Field The results are organized in an- 3 and Field 4 are characterized by nual emissions and total emissions values of the key parameters that hi- rage value of API gravity and field related to the life expectancy of the ghlight the emissions variation and depth typical of many Italian pro- field. help in model sensitivity analysis. duction sites. Field 2 has a much On the basis of total emissions, The set of selected input key para- higher field depth and WOR. Field the following emission indices are meters is the following (El-Houjeiri 3 is characterized by low value of calculated: – Greenhouse gas factor et al. 2013; EC 2015): API Gravity, field depth and WOR, while Field 4 (GHG factor); – Acidification fac- Field depth, and Water to Oil Ratio has a high value of API gravity and tor; – Photochemical oxidant factor; (WOR). Values are reported in table a mid/high value of WOR. We used – PM factor. These indicators are ex- 1 for each Field. Productivity and OPGEE default values for all other pressed in g equivalent of pollutants expected life time is kept equal to input parameters. relative to MJ of extracted natural 1500 bbl/d and 35 years, respectively Figure 1.a reports the emission gas. In this paper, we report on Gre- for all Fields. breakdown in process stages. Fugi- enhouse gas emissions only. Field 1 is characterized by an ave- tive emissions for all process stages

Fig. 1. GHG emissions for the 4 fictional oil fields and sensitivity to selected input parameters. . Fig. 1. Emissioni GHG per i 4 campi tipo e analisi di sensitività delle emissioni per parametri selezionati.

Dicembre 2017 27 environment are summed together and reported of Field 3 and Field 4 by ~ 78% and 3.2 Greenhouse emissions form as a separate contribution labeled as ~ 75%, respectively. Natural Gas production ‘VFF’ emissions. Total GHG emis- Figure 1.c reports the effect of sions vary from 8.4 gCO2eq/MJ of API gravity in the range 10 to 30. For running the Excel model ba- Field 1 to 25.8 gCO2eq/MJ of Field 2. Data do not show a significant in- sed on the NETL libraries, we defi- Emissions from flaring, venting and crease for any Field, with the largest ned two fictional fields (Field 5 and fugitive emissions (VFF) represent increase for Field 2 (~1.4%). This 6), which are an approximation of the most important source of GHG result shows that API gravity has a real Italian natural gas fields. The emissions for all the Fields, with the moderate influence on GHG emis- set of selected input key parameters exception of Field 2, for which the sions. is the following: Expected field life, high field depth and the high WOR Figure 1.d reports the effect of Field depth, Number of Wells, Na- cause high emissions of the produc- field depth in the range 1,000 to tural Gas Daily production volume. tion stage. 19,000 ft. For all Fields, increasing Values are reported in Table 2 for Figure 1.b reports the effect of filed depth increases GHG emissions each Field. WOR on total GHG emissions. by 20-30% Field 5 is characterized by a large Field 2, characterized by high values In conclusion, among the consi- depth and one productive well, whi- of WOR and field depth, shows the dered parameters, GHG emissions le Field 6 has a lower depth and five largest increase, i.e. GHG emission mostly depend on WOR and field productive wells. increase by ~ 86% when WOR in- depth, the latter being more relevant Figure 2.a reports the emission creases from 2 to 20. For the same when combined with high values of breakdown in process stages, as de- WOR increase, GHG emissions of WOR. Differently, GHG emissions scribed in the Emissions analysis Field 1 increase by ~ 79%, the ones depend only weakly on API. worksheet.

Fig. 2. GHG emissions for the 2 fictional gas fields and sensitivity to selected input parameters. Emissioni GHG per i 2 campi tipo e analisi di sensitività delle emissioni per parametri selezionati.

28 Dicembre 2017 ambiente

Tab. 2. Key parameters for each field. 4. Conclusions Emissions from Conventional Oil Parametri di input per ogni campo. Production Using an Engineering Field Expected Depth n. Natural Process-level detail models were Based LCA Model. In LCA XII, life [yr] [ft] wells gas volume selected and applied to calculate American Center for Life Cycle [ft3/d] greenhouse gas emissions from oil Assessment; Tacoma Washington, Field 5 10 1000 1 100,000 and natural gas production, respec- September 25−27, 2012. tively in a Well to Refinery Gate El-Houjeiri, H.M., Vafi, K., Duffy, J., Field 6 10 500 5 5.000.000 and Well to Tank prospective. Fic- McNally, S., Brandt, A.R., 2015a. titious fields were defined as an -ap OPGEE v1.1 DRAFT E. Excel spre- Most of emissions relate to the proximation of real Italian produc- adsheet model 2013. https://pan- processing stage, in particular to the tion fields. gea.stanford. edu/researchgroups/ operations of dehydration and com- Most of the emissions from oil eao/ accessed on 01/07/2017. pression and to the transport phase production relate to flaring, ven- El-Houjeiri, H.M., Vafi, K., Duffy, J., through pipeline, where energy is ting and fugitive emissions and to McNally, S., Brandt, A.R., 2015b. required to run the compressors. the production and processing pha- Oil Production Greenhouse Gas Emissions related to drilling and ses. Sensitivity analysis showed that Emissions Estimator OPGEE v1.1 completion of wells and spontaneous Field depth and Water to Oil Ration DRAFT E, User Guide and Techni- extraction are quite low. greatly affect greenhouse gas emis- cal Documentation, Department The GHG intensity of field A is sions. of Energy Resources Engineering, slightly higher because of the higher Most of the emissions from gas Stanford University: Stanford, CA. emissions due to drilling and well production relate to the surface pro- European Commission DG Energy, completion in a deeper well (1000 ft). cesses, in particular to the operations 2015. Study on actual GHG Data Fig. 2.b reports the effect of Field of dehydration and compression and For Diesel, Petrol, Kerosene And expected life GHG emissions. Incre- to the transport phase through pipe- Natural Gas asing expected life GHG emissions line, where energy is required to run Forster, P., Ramaswamy, V., Artaxo, P., decrease for both fields. Sensitivity the compressors. Emissions related Berntsen, T., Betts, R., Fahey, D.W., is larger for Field 5 than for Field 6. to drilling and completion of wells Dorland, R.V., 2007. Changes in The reason is related to the diffe- and spontaneous extraction are qui- Atmospheric Constituents and rent productivity of the fields, which te low. in Radiative Forcing. Cambridge, is much higher for Field 6 than for United Kingdom and New York, Field 5. NY, USA. Field 2.c reports the effect of Field U.S. Department of Energy, National depth, in the range 500 to 10,000 ft. References Energy Technology Laboratory, It is worth to remember that, in Fi- 2014. “Life Cycle Analysis of Natu- gure 2.c, at each depth, Field 5 con- El-Houjeiri, H.M., Brandt, A.R., Duffy, ral Gas Extraction and Power Ge- sists of a single well with that speci- J.E., 2013. Open-source LCA tool neration,” DOE/NETL-2014/1646, fic depth, while Field 6 consists of 5 for estimating greenhouse gas May 29. wells, whose combined depth sums emissions from crude oil produc- Vafi, K., and Brandt, A.R., 2014. Repro- up to the specific depth considered. tion using field characteristics. En- ducibility of LCA Models of Cru- Figure 2.c shows that GHG emissions viron. Sci. Technol. 2013, 47. de Oil Production Environmental of Field 5 increase significantly more El-Houjeiri, H., Brandt, A.R., 2012. Science & Technology 48, 12978- than the ones of Field 6. The reason is Exploring the Variation of GHG 12985. that Gas production of Field 5 is very low as compared to the one of Field 6, therefore, emissions due to drilling and Extraction impact on GHG (which is emission per MJ) more for Field 5 that for Field 6. Field 2.d reports the effect of natural gas daily volume. For low gas volume Field 6 has higher emissions than Field 5 because of slightly hi- Acknowledgement gher emissions in the drilling and Financial support by Ministero dello Sviluppo Economico, Direzione Generale extraction phase for the production per la Sicurezza anche ambientale delle attività minerarie ed energetiche is grate- of 5 wells rather than 1. fully acknowledged.

Dicembre 2017 29 ambiente

C. Martina* A methodology for the S. Bonvicini* assessment of environmental V. Cozzani* * Università di Bologna, DICAM, risk induced by offshore oil Dipartimento di Ingegneria Civile, Chimica, Ambientale e dei Materiali, spills Bologna

In the present study a methodology for the evaluation of the environmental risk induced by accidental oil spills occurring from offshore installations was developed, addressing in particular the impact oil weathering phenomena, governed of spills on the sea and on the coastlines. The necessity of developing a risk assessment methodology by oil properties, spill features and for the environment derives from the poor attention reserved to this target by traditional procedures, environmental conditions. (ITOPF, which have addressed until now exclusively humans. Thanks to a recent increased environmental 2011a). By now, the scientific re- consciousness of institutions, industry and people, the new environmental policies more and more search has developed sophisticated require the protection of the environment. In fact, Directive 2013/30/EU on the safety of offshore mathematical models, implemented oil and gas operations has introduced more strict requirements for the protection of both the wor- into specific software tools, that allow kers and the environment, that are the targets which could be involved and seriously damaged by to forecast the trajectory and the fate incidents occurring on offshore installations. The methodology developed for the assessment of the risk for the sea water and the coasts produces specific quantitative risk indexes, based on credible of the spilled oil (Spaulding, 2017). spill events, wind and sea conditions and may support the implementation of remediation strategies. These models depend upon the oil Keywords: environmental risk, oil spills, offshore installations, sea pollution, Directive 2013/30/EU. properties, the spill features, the evolution over time of wind and sea con- Metodologia per il calcolo del rischio ambientale dato da sversamenti accidentali di ditions in the spill area and the appli- olio in mare. Nel presente lavoro si illustra una metodologia per il calcolo del rischio di contami- cation of remediation strategies. Oil nazione ambientale causato da sversamenti accidentali di olio da installazioni in mare, con partico- spill simulations can be implemented lare attenzione all’impatto di tali sversamenti sul mare e sulle coste. La necessità di delineare una either “in real-time” or “a priori”. metodologia per la valutazione del rischio per il bersaglio “ambiente” nasce dalla scarsa attenzione The first case is useful for carrying out verso tale bersaglio da parte delle tradizionali procedure di calcolo del rischio, che finora sono state emergency response immediately af- indirizzate quasi esclusivamente al bersaglio “uomo”. Grazie ad un recente aumento di sensibilità ter the occurrence of a spill (ISPRA nei confronti dell’ambiente da parte delle istituzioni, dell’industria e della collettività, le nuove politiche ambientali richiedono con sempre maggior forza la protezione dell’ambiente. A tal proposito, and MATTM, 2014), while the lat- la Direttiva 2013/30/EU sulla sicurezza delle operazioni in mare nel settore degli idrocarburi intro- ter is useful to estimate environmen- duce prescrizioni specifiche per la prevenzione e la protezione sia dei lavoratori che dell’ambiente, tal risk caused by a specific offshore ovvero dei bersagli che potrebbero entrambi essere coinvolti e gravemente danneggiati da eventi installation, such as an offshore oil incidentali che si verifichino a carico delle installazioni in mare e delle operazioni connesse con tali platform, both to verify if risk is ac- impianti. La metodologia messa a punto per la stima del rischio di contaminazione del mare e delle ceptable and to produce a set of sce- coste produce degli indici di rischio quantitativi, appositamente definitivi, sulla base di plausibili rila- narios to allow in advance emergency sci accidentali di olio, delle condizioni meteo-marine ed eventualmente della messa in atto di misure response planning (ITOPF, 2011b; di intervento d’emergenza. Nel presente lavoro la metodologia è descritta in dettaglio ed applicata, IPIECA-IOGP, 2013), as also requi- a titolo esemplificativo, ad alcuni casi di studio. red by Directive 2013/30/EU (Direc- Parole chiave: rischio ambientale, rilasci di olio, installazioni in mare, contaminazione ambientale, tive 2013/30/EU). Direttiva 2013/30/EU. Directive 2013/30/EU introduces the obligation to perform an environmental risk analysis in the context 1. Introduction oil spills caused by offshore installa- of major accident risk assessment, in tions. The risk refers to the impact of order to verify if risk is acceptable Risk analysis methodologies the oil on both the sea and the coast, and to produce a consistent base of usually allow the evaluation of quan- in absence and in presence of inter- risk indexes for planning emergency titative risk indexes assuming hu- vention strategies for minimizing the response. In this context, the aim mans as the only target. The objec- impact of the spill. of the study carried out is the deve- tive of the research presented in this A mixture of liquid hydrocarbons lopment of a new methodology for paper is the development of a quan- released at sea tends to modify due to the assessment of environmental risk. titative methodology to evaluate the several simultaneous physico-chemi- The paper has the following struc- risk of environmental pollution of cal processes, collectively known as ture: after this introduction, section

30 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 ambiente

2 contains the definition of specific to negligible concentrations, wi- In order to explain how the proce- environmental risk indexes and the thout any significant damage. Dissol- dure works, in the following section explanation of the steps of the me- ved oil strictly depends on dispersed its application to some case-studies thodology, while section 3 contains oil. Therefore, the physical quanti- is described and discussed in detail. the detailed description of its appli- ties that can be used to express the cation to case-studies. Finally, section effects of an oil spill are: 4 contains some conclusive remarks. – the quantity of oil in the slick; – the quantity of oil dispersed in the 3. Case-studies water column; – the quantity of beached oil. In the case-studies, three ficti- 2. The methodology By reference to these physical ef- tious offshore installations were con- fects, three risk indexes for the ma- sidered, sited in correspondence of The methodology developed for rine environment can be defined, existing Italian oil exploitation rigs the assessment of environmental represented by the F/MassOilSlick, and characterized with realistic data. risk of offshore operations takes into the F/MassDispersedOil and the F/ account Article 2 of the Directive MassBeachedOil curves drawn in the 2013/30/EU, where “risk” is defined Cartesian plain. In these curves F 3.1. Description of the risk as “the combination of the probability of is the cumulated frequency of acci- sources an event and the consequences of that dental oil spills occurring on the of- event”. In order to calculate quan- fshore installation under exam cau- Three fictitious FPSO (Floating, titative risk indexes for the marine sing quantities of oil in the slick, in Production, Storage and Offloading) environment, it is thus necessary to the water column and on the beach units where considered: first estimate the likelihood and the equal or greater, respectively, than 1. unit SARA in the Adriatic Sea; consequences of oil spills and then MassOilSlick, MassDispersedOil and 2. unit ROSA in the Adriatic Sea; to combine them into specific risk MassBeachedOil. These risk indexes 3. unit VERA in the Strict of Sicily. indexes. are clearly similar to the F/N curves All units were supposed to produ- that are traditionally used to express ce an oil with 18.7 °API. The sites social risk for humans, where F re- considered for the FPSO units are 2.1. Risk indexes for the marine presents the cumulated frequency of shown in Figure 1. environment accidents causing at least N fatalities.

Oil behaves as a Light Non 3.2. Description of the marine Aqueous Phase Liquids (LNAPL), 2.2. Steps of the procedure environment since it is insoluble in water and has a density lower than water. As a con- As a consequence of the strict The marine environment in the sequence, in case of on-surface spills, analogy of the environmental risk area of the installations has to be it immediately forms a separate li- curves with societal risk plots, the characterized with the environmen- quid phase – an oil slick – floating procedures for their estimation are on water. The main physical effects fully comparable. In particular, the of a LNAPL spillage at sea are: 1) methodology for environmental risk spreading and advection of the oil assessments consists of the following slick; 2) natural dispersion of small steps: oil droplets from the lower surface of 1. description of the risk sources; the slick into the water column; 3) 2. description of the marine envi- evaporation of the volatile fractions ronment around each risk source; of the oil from the upper surface of 3. identification ofspill events and the slick; 4) dissolution of the solu- estimation of their frequencies for ble fractions of oil into the water co- each risk source; lumn, mainly from the oil droplets; 4. estimation of the physical effects 5) oil beaching, when the slick rea- of spill scenarios; ches the coastline. 5. combination of the physical ef- In order to define the envi- fects and the occurrence frequen- ronmental risk indexes, evaporated cies of all spill scenarios, in order oil is not considered, because it ra- to obtain the environmental risk Fig. 1. Location of the case studies. pidly disperses into the atmosphere indexes. Ubicazione dei casi di studio.

Dicembre 2017 31 environment tal parameters which determine the the MAJOR category was characte- 3.4. Estimation of the physical trajectory and the fate of the spil- rized by the mass values of oil spilled effects of spill scenarios led oil. These parameters are repre- during 4 major accidents belonging sented mainly by wind and current to this category, occurred between In order to evaluate the transport fields. Suitable data were downlo- 1992 and 2015 on the United King- and weathering processes of the oil aded from the Copernicus Marine dom Continental Shelf and reported spill, the OSCAR – Oil Spill Con- Environment Monitoring Service in a the HSE offshore spills databa- tingency And Response tool of the (Marine Copernicus, 2016), which se (HSE, 2016b). Though the HSE MEMW – Marine Environmen- provides 2D 6-hours-averaged wind databank reports different durations tal Modelling Workbench packa- data and 3D 24-hours-averaged cur- for each spill, this input was taken ge developed by SINTEF was used rent data; data referring to the year equal to 1 day for all categories, ha- (SINTEF, 2016). The OSCAR tool 2015 were considered. ving verified its limited influence was run in the stochastic modali- on the results. The same database ty, which means that the same spill was analyzed in order to find out was simulated in 24 different sea 3.3. Identification of the spill the occurrence probabilities of the and wind conditions during the year events and estimation of their MAJOR and SIGNIFICANT spills, 2015, assuming each spill as starting frequencies which were calculated considering on the 1st and 15th of each month. the numbers of spills belonging to Thus, being Pcond k = 24/365 the oc- The methodology is able to each category recorded in the data- currence probability of a set of sea handle both sub- and on-surface bank (HSE 2016b). Table 1 reports and wind conditions, the occurrence spills of oil, as well as spills of other the characterization of the oil spills frequency of spill category i in condi- liquids which are generally present based on the above mentioned cri- tions k is given by equation (2): in offshore units, for instance mari- teria. f = f · P (2) ne diesel. For the sake of simplicity, In order to estimate the occurren- spill i, cond k spill i cond k only spills of oil on the sea surface ce frequency fspill i of each spill cate- The results of the mass balance were taken into account for the con- gory i, it is necessary to apply equa- of the spill – the so-called oil bud- sidered case-studies. tion (1): get – vary with time, as obvious; for The identification of the spills f = f · P (1) the purpose of evaluating the envi- was carried out based on the British spill i spill spill i ronmental risk indexes, results in Health and Safety Executive crite- where fspill is the yearly spill fre- terms of MassOilSlick, MassDisper- ria, which divide spills in the fol- quency of an offshore installation sedOil and MassBeachedOil at 5 days lowing categories (HSE, 2016a): and Pspill i is the occurrence probabi- after the spill were obtained for each MAJOR: spilled mass > 9000 kg; lity of the ith spill category. The ye- spill category i in all sea and wind SIGNIFICANT: spilled mass in the arly spill frequency fspill was assumed conditions k. In fact, the time win- range 60 kg ÷ 9000 kg; equal to 0,05 events/year/offshore dow during which implement reme- MINOR: spilled mass < 60 kg. unit, which is an approximate va- diation strategies is usually short: it For estimating the environmental lue of the occurrence frequency of starts at the beginning of the spill risk, the MINOR category was ne- SIGNIFICANT and MAJOR spills and ends within a few days. For this glected, in accordance to Regulation derived from the HSE offshore spill reason, in order to estimate the in- n. 1112/2014 (Reg. 1112/2014). The database (HSE, 2016b) and the ye- fluence of emergency response on SIGNIFICANT category was assig- arly average number of operating the spill, the time of 5 days is sui- ned a spilled mass of 5000 kg, while units. table.

Tab. 1. Characterization of oil spills for an offshore unit based on the HSE offshore spill database. Caratterizzazione dei rilasci di olio per un’installazione offshore secondo i criteri HSE. Category ID Ranges of spilled mass Number of spills Values of mass used in calculations Occurrence probabilities i kg Nspill,i kg Pspill,i 1 60 ÷ 9000 123 5000 0,968 2 1 17000 0,008 3 1 25000 0,008 > 9000 4 1 32000 0,008 5 1 80500 0,008

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risk to the water column, which is itself greater than the risk to the coastline. However, because of the difference in the sea and wind conditions of the 3 units, the risk they cause to the same environmental compartment is different: for instance, unit ROSA produces a risk Fig. 2. Environmental risk indexes for unit ROSA: a) risk curves; b) expected yearly to the sea surface which is greater quantities of released oil. (nearly double, in terms of expected Indici di rischio ambientale per l’unità ROSA: a) curve di rischio; b) masse annue di olio oil mass), than the risk caused to attese. the sea surface by unit VERA. Unit VERA causes no risk to the coast- 3.5. Combination of the is analogous to the PLL – Potential line – the oil spilled by unit VERA physical effects and the Life Loss derived from F/N curves, never reaches the strand – while occurrence frequencies into the which represents the yearly ex- unit SARA causes to the coastline risk indexes pected number of fatalities. Looking a risk that is greater of about a fac- at Figure 2b, where the quantities tor of 10 than the risk to the beach By combining in the same way of oil expected on the sea surface, of unit ROSA. As a last result, the adopted for obtaining F/N curves the water column and the beach influence on risk of emergency re- (Ball and Floyd, 1998) the occur- are plotted, it is confirmed that the sponse is shown in Figure 4. rence frequencies and the results of mass of oil expected on the coastli- The intervention strategies that the oil budget for each spill i in all ne is much lower that the oil disper- may be adopted to contrast an oil conditions k, the environmental risk sed in the water column, which is spill are oil containment and me- indexes are obtained. Some results itself lower than the oil in the slick. chanical recovery, application of for the 3 case-studies are presented Figure 3 compares the environmen- dispersants in order to stimulate the in the following. tal risk – represented by curves and dispersion of oil from the slick into Figure 2a shows the risk curves yearly expected masses – of the 3 the water column, protection of the for the unit ROSA. It can be im- case-studies. shorelines. For the sake of simplicity, mediately observed that the curves Looking at Figure 3, it can be only containment and recovery were are different, putting in evidence a noted that for all units the risk to assumed for the case-studies, consi- different damage effect on the diffe- the sea surface is greater than the dering the use of a 250 m long boom, rent environmental compartments, i.e the sea surface, the water column and the coastline. The F/ MassBeachedOil plot not only shows that for the unit ROSA the quantity of beached oil is generally lower than the mass of oil on the sea surface and in the water column, but also highlights – having a lower frequency than the other two curves – that beaching does not occur in all spill situations, that is, there are combinations of spill categories and sea and wind conditions for which the oil does not reach the coastline within 5 days. From each risk curve it is possible to obtain another risk index, estimating the area beneath Fig. 3. Environmental risk indexes for the case-studies: a) F/MassOilSlick curves; b) F/ the plot, in strict analogy with the MassDispersedOil curves; c) F/MassBeachedOil curves; d) expected yearly quantities of representation of societal risk (Ball oil in the environmental compartments. and Floyd, 1998): the mass of oil ye- Indici di rischio ambientale per i casi di studio: a) curve F/MassOilSlick; b) curve F/MassDi- arly expected in each environmen- spersedOil; c) curve F/MassBeachedOil; d) masse annue di olio attese nei comparti am- tal compartment is obtained, which bientali.

Dicembre 2017 33 environment

bientali e valutazione delle tipologie d’intervento”, Istituto Superiore per la Protezione e la Ricerca Am- bientale e Ministero dell’Ambien- te e della Tutela del Territorio e del Mare, Roma. ITOPF, 2011a, Fate of marine oil spills, Technical Information Paper n. 2, International Tankers Owner Pol- lution Federation, London. ITOPF, 2011b. Contingency planning for marine oil spills, Technical Informa- tion Paper n. 16, International Tan- kers Owner Pollution Federation, London. Reg. 1112/2014. Regulation n. 1112/2014 of European Commis- sion of 13 October 2014: A com- Fig. 4. Influence of mechanical recovery on the environmental risk indexes for unit mon format for sharing of informa- ROSA. tion on major hazard indicators by Influenza del recupero meccanico sugli indici di rischio ambientale per l’unità ROSA. the operators and owners of offsho- References re installations and a common for- a skimmer with a rate of 50 m3/h and mat for the publication of the infor- an offshore storage capacity or reco- Ball, D.J.and Floyd, P.J., 1998. Societal mation on major hazard indicators 3 vered oil of 200 m . Looking at Fi- Risks, Report commissioned by by the Member States. gure 4, it can be immediately noted 1032 HSE, London. Spaulding, M., 2017. State of the art re- that mechanical recovery reduces Directive 2013/30/EU, Directive view and future directions in oil spill the risk for all environmental com- 2013/30/EU of the European Par- modeling, Marine Pollution Bullet- partments; in particular, it nearly liament and of the Council of 12 tin, 115(1-2), pp. 7-19. halves the yearly expected oil mass June 2013: Safety of offshore oil and HSE, 2016a. https://www.hse. in the slick. gas operations and amending Di- gov.uk/hcr3/help/help_pu- rective 2004/35/EC. blic.asp#Severity, accessed on IPIECA-IOGP, 2013. Oil spill risk as- 23/10/2016. sessment and response planning for HSE, 2016b. http://www.hse. 4. Conclusion offshore installations, International gov.uk/offshore/statistics/ Association of Oil and Gas Produ- hsr1992%E2%80%932014.xlsx, A methodology for the estima- cers – Global oil and gas industry accessed on 3/10/2016. tion of environmental risk caused association for environmental and Marine Copernicus, 2016. http://ma- by accidental oil spills from offshore social issues, London. rine.copernicus.eu, accessed on installations was developed and ap- ISPRA and MATTM, 2014. Quaderno 15/12/2016. plied to some case studies, highligh- delle emergenze ambientali in mare SINTEF, 2016. https://www.sintef.no/ ting its potentiality in fulfilling the n.01 “Sversamento di idrocarburi in en/software/oscar/, accessed on requirements of Directive 2013/30/ mare: stima delle conseguenze am- 12/12/2016. EU. In the near future, the procedure will be extended to integrate the possibility to include subsea spills in addition to on-surface spills and to consider the influence of the application of dispersants in addition to mechanical recovery. Acknowledgement The study was carried out in the framework of the Research Project “Network for Offshore Safety”, funded by the Italian Ministry of Economic Development, Directorate-General for Safety of Mining and Energy activities, National Mining Office for Hydrocarbons and Georesources (DGS-UNMIG).

34 Dicembre 2017 ambiente

M. Rovere* Natural hydrocarbon seepage E. Campiani* E. Leidi* in the Italian offshore A. Mercorella*

* Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche Italy hosts the largest petroleum systems in southern Europe and is the third EU country for oil (CNR-ISMAR), Bologna reserves after Norway and UK and fifth for gas reserves (as 2015). Of the 167 fields currently in production, about 60 are located in the Italian offshore and specifically in the Adriatic and Ionian region (Adriatic Sea, Ionian Sea, Strait of Sicily), which corresponds to the “marine zones” A, B, D, F and G of the Italian continental shelf, open for hydrocarbon exploration and exploitation under the governance of the Ministry of Economic Development. Italy is third for offshore gas, 1. Introduction sixth for oil production (as 2012) among EU countries. Petroleum systems in the Italian seas can be grouped into: biogenic gas in the terrigenous Plio-Quaternary wedges (northern and central 1.1. Hydrocarbons in the Adriatic, Panda field); thermogenic gas in the terrigenous Tertiary foredeep systems (Luna field); oil marine realm and thermogenic gas in the Mesozoic carbonates (southern Adriatic, Rospo, Gela, Vega fields). In addition to these deep reservoirs, the Italian seas are characterized by the presence of significant Hydrocarbons are organic com- hydrocarbons in the shallow sediments, which sometimes seep to the seabed and the water col- pounds that contain only carbon and umn. This study aims to produce the definitive map of the natural emissions of hydrocarbons at the hydrogen atoms. In nature, hydro- seabed and in the water column in the Italian seas, by analysing high resolution seismic reflection carbons, both as gaseous (methane data obtained using high frequency systems, bathymetric and reflectivity data of the sea-bottom C1, ethane C2, propane C3, butane and the water column acquired with the ultimate generation of multi-beam systems, owned by C4) and liquid phases (benzene, he- CNR-ISMAR. Where no CNR-ISMAR data are available, information from literature will be used. The objectives are: morphological classification (volcanoes and mud diapirs, pockmarks); detection xane, octane etc, all represented by of flares in the water column; geochemical characterization, when achievable, between biogenic the symbol C5+), are mainly found and thermogenic gas; link to deep sources, such as diapirs and faults; a better understanding of the in the porosity of the rocks that make causal relationship with slope instability and soft-sediment deformation (geohazard), especially in up the upper continental crust and the vicinity of Oil&Gas plants. are the product of chemical-physi- Keywords: biogenic gas, gas plume, Adriatic and Ionian region, pockmark, water column reflectivity. cal processes that may persist for thousands and / or millions of years. Emissioni naturali di idrocarburi nei mari italiani. L’Italia possiede i più grandi sistemi pe- Hydrocarbons having lower molecu- troliferi dell’Europa meridionale ed è terzo paese per riserve di petrolio in EU dopo Norvegia e UK lar weight are found in the gaseous e quinto per riserve di gas (2015). Dei 167 campi attualmente in produzione su tutto il territorio state, those with higher molecular nazionale, circa 60 si trovano nei mari italiani e nello specifico nella regione Adriatico e Ionica (Mar weight are liquid or waxy solids. Adriatico, Mar Ionio, Stretto di Sicilia), che corrisponde alle “zone marine” A, B, D, F e G della piatta- Marine environments are ideal for forma continentale italiana, aperte alla ricerca e coltivazione di idrocarburi in mare, su conferimento the formation of hydrocarbons, be- dei titoli minerari da parte del Ministero dello sviluppo economico. Per quanto riguarda la produzione offshore in EU, l’Italia è terza per gas, sesta per petrolio (2012). I sistemi petroliferi nei mari cause organic matter (e.g. plankton italiani si possono raggruppare in: gas biogenico nei cunei terrigeni di avanfossa Plio-Quaternaria and phytoplankton, terrestrial and (Adriatico settentrionale e centrale, campo Panda); gas termogenico nei sistemi terrigeni terziari marine vegetation) falls out in lar- di avanfossa traslati in catena (campo Luna); petrolio e gas termogenici nei carbonati mesozoici ge quantity on the sea bottom and (Adriatico meridionale, campi Rospo, Gela, Vega). Oltre a questi giacimenti profondi, che sono ogget- rapidly undergoes anaerobic degra- to di sfruttamento, i mari italiani si caratterizzano per la presenza di significative quantità di idro- dation for the anoxic conditions. In carburi nei sedimenti superficiali, che talvolta fuoriescono dal fondo mare e risalgono nella colonna addition, also high and fast sedimen- d’acqua. Questo studio si propone la mappatura completa delle emissioni naturali di idrocarburi a tation rates, typical of certain marine fondo mare ed in colonna d’acqua, non sfruttate ai fini energetici, attraverso l’analisi di dati sismici a depositional environments, favour riflessione ad alta risoluzione ottenuti con sistemi ad alta frequenza, dati batimetrici e di riflettività rapid burial and decomposition of del fondo e della colonna d’acqua acquisiti con ecoscandagli multifascio di ultima generazione, organic matter, due to increasing posseduti da CNR-ISMAR. Laddove non sono presenti dati CNR-ISMAR, sono utilizzate tutte le in- temperature with depth. Methane formazioni disponibili in letteratura. Gli obiettivi sono: la classificazione su base morfologica (vulcani is by far the most common gas in e diapiri di fango, pockmark); l’individuazione di emissioni in colonna d’acqua; la distinzione, laddove possibile su base geochimica, tra gas biogenico e termogenico; la connessione con sorgenti profonde, the sedimentary rocks of the Earth’s strutture diapiriche e faglie; la migliore comprensione della relazione con fenomeni di instabilità di crust and deep marine sediments are scarpata e deformazioni superficiali dei sedimenti (geohazard), in prossimità degli impianti di sfrut- the largest reservoir of methane, mo- tamento degli idrocarburi. stly in their hydrate form (104 Gt of Parole chiave: gas biogenico, gas plume, regione Adriatico-Ionica, pockmark, riflettività della co- C, Kvenvolden, 1988). Some esti- lonna d’acqua. mates indicate that various sources

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 35-40 35 environment of methane annually inflow into the ted gas (which will not be discussed of repeated phases of subaerial expo- oceans 0.02 Gt of C, although most here because these structures are sure and drowning, especially since is thought to sink in the carbonate unlikely present in the Italian seas, the Last Glacial Maximum (LGM). precipitation-related process (Bo- based on the gas-hydrate stability Fluid seepage is due to several factors etius and Wenzhöfer, 2013). The zone predictability models). and often is linked to the deep reser- hydrocarbon generation can be ei- When the flow is sufficiently voirs in the area. The Ionian Sea is ther a microbic or a thermic process. high, methane can escape the sea- bordered by the Apulian and Malta In microbial processes (biogenic bed and form gas plumes in the wa- Escarpments that formed by rifting gas), organic matter is decomposed, ter column. These can be detected in the Mesozoic or Permo-Trias essentially generating pure methane, as density anomalies by marine ge- (250 Ma), as passive margins of the through a sequence of chemical reac- ophysical instruments. Up to 10 to Tethys ocean. Nature and age of the tions mediated by specialized bacte- 15 years ago, only the echo sounder, crust are still debated between oce- rial communities living in anoxic used to measure the depth of the anic and thinned continental but, sediments. It is generally accepted water column beneath a ship, and currently most of the crust has been that this occurs at < 50 °C (Stolper the side scan sonar, which is a deep- consumed in a NW-directed subduc- et al., 2014) and ubiquitously in ma- towed sonar-system that measures tion underneath the Calabrian Arc. rine environments, < 1 km from the the intensity of acoustic reflections, The SE-ward advance of the Cala- seabed (Whiticar et al., 1986). Ther- were available for this purpose (Paull brian-Peloritan block drove shorte- mic processes (primary thermogenic et al., 1995). Today, these plumes ning and thrusting in the Tertiary gas), on the other hand, are based can be measured and displayed in thick cover of sediments leading to on the thermic decomposition of 3D thanks to modern multibeam sy- the build up of a large accretionary the organic matter (cracking of the stems (Chadwick et al., 2014). This wedge. Compressive faulting here is kerogene), normally at temperatures acquisition technique allows to de- responsible for the majority of the exceeding 150-160 °C. Secondary termine the exact position and size fluid escape structures, mainly mud thermogenic gas formation, from of the gas plume in water and, when volcanoes, but also normal faults al- oil cracking, occurs at < 150-160 °C coupled with acquisition of hydrolo- low seepage of fluids towards the se- (Stolper et al., 2014). Biogenic gas is gical data, can quantify the upward abed. The Adriatic Sea initially for- not necessarily linked to a petroleum flux or dissolution of gas (Schneider med as a passive margin during the system, but may migrate in strati- von Deimling et al., 2011). rifting of the Pangea Supercontinent graphic or structural traps where is about 270-250 Ma, but today, within rapidly buried. Biogenic gas can ac- the convergence/collision between cumulate in large quantities and in 1.2 Geological setting Africa and Europe broader geodyna- fact represents about 20% of global mic context, represents the forede- natural gas resources (Rice and Clay- The study area encompasses dif- ep and foreland of the Apennines pool, 1981). Although empirical me- ferent geodynamic contexts sur- and Dinarides mountain belts. It is thods have been developed to clas- rounding Italy mainland and can overlain by continental crust and is sify biogenic and thermogenic gas, be arbitrarily subdivided into: the a relatively shallow sea (average 50 based on the geochemistry of C and Strait of Sicily, the Ionian Sea and m in the North, max 1200 m in the H stable isotopes (Whiticar, 1999), the Adriatic Sea (Fig. 1). The nor- South). In the northern Adriatic there are uncertainties, especially thern Strait of Sicily represents the Sea, the last glacial-eustatic cycles, given that gases can have multiple foredeep and foreland of the Magh- which led several times to subaerial sources and that hydrocarbon gas rebian mountain chain, it is a shal- exposure and erosion, favoured the venting at the seafloor or seeping in low (average 130-m-deep) platform formation of biogenic gas in the fi- the shallow subsurface may have ex- paved by thinned continental crust, ner and richer organic matter layers, perienced post-generation bacterial contains ancient Mesozoic deep car- intertwined with sands, which beca- oxidation during upward migration bonate platforms, relatively deep me large reservoirs now exploited for (Coleman et al., 1981). NW-SE oriented troughs (> 1000 hydrocarbon production (Fig. 1). Hydrocarbons tend to migrate to m) opened as grabens during the late shallower sedimentary horizons and Miocene transtension tectonics and eventually to “pierce” the seabed, Plio-Pleistocene rifting, was mostly giving rise to peculiar seafloor fea- exposed during the Messinian sali- 2. Materials and methods tures. These can be categorized in: nity crisis (5.9-5.3 Ma, million years pockmarks (Hovland et al., 1984), ago) and volcanism has been very For the scope of the project, we mud volcanoes (Mazzini and Etio- active starting 1 Ma. The present- have used a large database of geo- pe, 2017), pingoes formed by hydra- day seafloor morphology is the result physical and geological data which

36 Dicembre 2017 ambiente

Fig. 1. Mappa batimetrica (risoluzione orizzontale 230 m) e schema tettonico semplificato dell’area di studio che mostra i fronti principali delle catene, il cuneo di accrezione dell’Arco Calabro, il livello del mare durante l’ultimo massimo glaciale (LGM, linea nera tratteggiata) e le piattaforme di sfruttamento degli idrocarburi nei mari italiani. Sono mostrati, inoltre, i dati sismici e di ecoscanda- glio multifascio in possesso a CNR-ISMAR ed utilizzati per questo studio. Bathymetric map (spatial resolution 230 m) and schematic tectonic sketch of the study area showing the major thrust fronts, the Ca- labrian accretionary wedge, the sea level during the Last Glacial Maximum (dashed line), and the offshore plants for the hydrocarbon exploitation in the Italian seas. The Seismic and Multi Beam Echo Sounder data sets, owned by CNR-ISMAR, are also shown. have been acquired by CNR-ISMAR swath bathymetry, hundreds of sedi- HIPS & SIPS; water column reflec- during a long time span (1991-2016). ment cores (Fig. 1). Where our data tivity data have been post-processed This dataset consists of: 130 x 103 km are sparse, we have used literature using FMMidwater (QPS software), of single channel very high and high information by georeferencing data designed to show water column data resolution seismic profiles of diffe- sources and maps, using the software with their exact position in space rent technologies (Compressed Hi- ESRI ArcGIS. Bathymetric and sea- and time, preserving relevant in- gh-Intensity Radiated Pulse CHIRP; floor reflectivity data have been post- formation as time-based navigation sparker); 25 x 103 km2 of multibeam processed using the suite CARIS and attitude. Water column featu-

Dicembre 2017 37 environment

Fig. 2. Esempio di plume di metano visualizzato nella colonna d’acqua, attraverso il sistema multibeam Kongsberg EM 710, in Adria- tico centrale, 60 km al largo di Ancona, non lontano dai campi di estrazione di gas “Bonaccia”. Profondità dell’acqua 80 m. A lato un’immagine di un profilo CHIRP che passa sopra il plume ed intercetta le continue emissioni. Methane plume in the water column, acquired by means of the Kongsberg EM 710 multibeam system, central Adriatic Sea, 60 km off shore Ancona, not far from the Bonaccia field. Water depth 80 m. Aside, sub-bottom seismic CHIRP profile over the plumes, which images different plumes in time. res have been imported as clouds of maximum flooding surface (mfs), only once by Etiope et al. (2014). In points into the 3D Fledermaus sof- formed when marine sediments rea- the southern Adriatic Sea, a large tware (version 7.3). Each point com- ched their most landward position deep reservoir of thermogenic gas it posing the 3D flare is georeferenced (i.e. the sea reached its present seal is known to be present around the and each colour may represent its level position), around 5,500 years Aquila field, but there is no eviden- height in the water column, amplitu- ago. The HST is capped by a sequence of upward connection along the de or number of beams (Fig. 2). ce boundary and lies below meters- continental slope, even because a thick prograding clinoforms. 4081 large, 40-m-thick, landslide seals km2 of gas, which thickness is less the deeper deposits. On the contra- assessable because of the depth, are ry, there are peculiar structures, less 3. Preliminary results trapped in the Transgressive Systems than 10-m-tall, emplaced in sandy Tract (TST in Fig. 3), which com- sediments, on the continental shelf Mapping of gas and gas-permea- prises the deposits that accumulated that have conical shapes and small ted sediment can be subdivided in from the onset of the last coastal ma- crater-like structures on top. In the different groups in the Adriatic and rine transgression until the time of northern Ionian Sea there are large Ionian region (Fig. 3). In the nor- maximum transgression of the coast (up to 200 m in diameter) pockmar- thern and central Adriatic, there (19,000-6,000 years ago). These la- ks, on main structural trends, which is widespread presence of past and yers are not substantially connected are most probably connected, along active methane seeps that favou- to the seafloor by seepage. Pockmar- normal faults, with fluids buried in red the precipitation of methane- ks, 50-70 m in diameter, are present the Miocene sedimentary succes- imprinted authigenic carbonates on in the Mid Adriatic Deep where flu- sion (> 1.5 km in the sub-seabed). the seafloor, these seeps may be or ids escape from deeper underlining On top of the accretionary wedge not be connected to deeper rooted units, probably because here the gas- present in the Ionian Sea, there is fault systems. In the central Adria- permeated layers have been unroo- a large province of mud volcanoes, tic, there is a 3336 km2 layer of gas, fed by mass wasting processes. The well documented in literature that averagely 25-m-thick, trapped in the only known oil seepage is located probably hosts more edifices than High Stand Systems Tract (HST in in the central Adriatic, about 1-2 those discovered up to date. In the Fig. 3), that constitutes the upper km offshore the village of Fontespi- Strait of Sicily, there is an area, close systems tract of the stratigraphic na in the Marche region, at a water to the Vega field and between Sicily sequence, and lies directly on the depth of 10 m, which was sampled and Malta, where small height (5 m)

38 Dicembre 2017 ambiente

tion multibeam systems, which are now capable of imaging in detail both the morphology of the seafloor and the water column. These can be coupled with high vertical resolution sub-bottom seismic data to understand the connecting path of the plumbing system. When the plumbing system is located deeper, as for the case of the gas trapped in the Miocene sedimentary succession and connected along faults to the seafloor, multichannel seismic data are needed to locate the source of the gas. To understand the actual composition of the gas, between thermogenic or biogenic origin, direct geochemical analysis over the hydrocarbon fluids is needed. This is also important in terms of assessment of the potential for exploitation. This study is the first effort ever to compile a general map and catalogue of the natural hydrocarbon seepage in the Italian offshore. There is still lack of data especially on the continental shelves, where high resolution data are necessary, but come at higher costs in terms of ship-time, because shallower the water depth narrower is the width of the insonified seafloor, resulting in small survey coverage compared to deep waters. Furthermore, more efforts should be paid especially in the geophysical and geochemical monitoring of seepage located close to the coasts, where they may Fig. 3. Mappa preliminare di tutte le emissioni ed emanazioni naturali di idrocarburi a interfere with tourism and leisure fondo mare e nella colonna d’acqua nella regione Adriatico e Ionica. activities, and being of concern for Preliminary map of natural hydrocarbon seepage in the Adriatic and Ionian region. public health. For example, episo- dically, along a stretch of coast near 200-m-diameter circular features are in several places and also here are as- Civitanova Marche, central Adria- interpreted as mud volcanoes, some sociated with authigenic carbonate tic Sea, bathers complain about of them present water column plu- precipitation. episodes of oil spills in the water mes in the sub-bottom seismic data. (http://www.cronachemaceratesi. Furthermore, ridge-like remnant it/2014/08/12/acqua-inquinata- structures of the LGM host small e-cattivi-odori-tra-fontespina-e- conical muddy structures on top. At 4. Conclusions porto-potenza/561112/;http://www. the toe of the continental slope, in cronachemaceratesi.it/2013/06/24/ the vicinity of the Gela and Panda For quickly achieving a comple- chiazze-e-gasolio-in-mare-deci- fields, where several mass-transport te mapping of fluid escapes in the ne-di-segnalazioni-alla-capitane- deposits have been emplaced during marine domain, the very first step ria/342690/). The cause is often the Late Quaternary (< 1 Ma), few is the geophysical investigation by searched in a ship’s or a nearby of- 250-m-large pockmarks are scattered means of high frequency/resolu- fshore plant’s spill, but, most proba-

Dicembre 2017 39 environment bly, these liquid hydrocarbons come and Scotian Shelf. Sedimentology eps. Geochemistry, Geophysics, from a natural source present very 31. pp. 471-80. Geosystems 8, Q06004. close to the beach (1 km offshore). Kvenvolden, K.A., 1988. Methane Stolper, D., Lawson, M., Davis, C.L., The seep emits ethane and propa- hydrate – A major reservoir of car- Ferreira, Santos Neto, E.V, Ellis, ne, which are photochemical pollu- bon in the shallow geosphere? Che- G.S., Lewan, M.D., Martini, M., Tang, tants, in the water, while the sedi- mical Geology 71, pp. 41-51. Y., Schoell, M., Sessions, a L., Eiler, ments around the seep are naturally Mazzini, A., Etiope, G., 2017. Mud vol- J.M., 2014. Gas formation. Forma- enriched with benzene and non-vo- canism: An updated review. Earth- tion temperatures of thermogenic latile aliphatic hydrocarbons. We Science Reviews 168. pp. 81-112. and biogenic methane. Science 344, propose the implementation of a Paull, C.K., III, W.U., Borowski, W.S., pp. 1500-1503. geophysical and geochemical moni- Spiess, F.N., 1995. Methane-rich Whiticar, M.J., 1999. Carbon and toring programme, with periodical plumes on the Carolina continental hydrogen isotope systematics of sampling of water and sediments rise: Associations with gas hydrates. bacterial formation and oxidation of near the seep, which may contri- Geology 23, pp. 89-92. methane. Chemical Geology 161, bute to the designing of a predicti- Rice, D.D., Claypool, G:E., 1981. Gene- pp. 291-314. ve model and a warning system for ration, Accumulation, and Resource Whiticar, M.J., Faber, E., Schoell, M., the benefit of local population and Potential of Biogenic Gas. AAPG 1986. Biogenic methane forma- tourists. This programme would be Bulletin, 65, 1, pp.5-25. tion in marine and freshwater envi- valuable both for societal challenges Schneider von Deimling, J., Brockhoff, ronments: CO2 reduction vs. acetate and for the better understanding of J., Greinert, J., 2007. Flare imaging fermentation-Isotope evidence. Ge- the natural phenomenon of hydro- with multibeam systems: Data pro- ochimica Cosmochimica Acta 50, carbon seepage, which is overlooked cessing for bubble detection at se- pp. 693-709. in our seas.

References

Boetius, A., Wenzhöfer, F., 2013. Sea- floor oxygen consumption fuelled by methane from cold seeps. Nat. Ge- osci. 6. Pp. 725-734. Chadwick Jr., W.W., Merle, S.G., N.J. Buck, J.W. Lavelle, J.A. Resing, V. Fer- rini, 2014. Imaging of CO2 bubble plumes above an erupting submarine volcano, NW Rota-1, Mariana Arc. Geochemistry, Geophysics, Geosystems 15, pp. 4325-4342. Coleman, D.D., Risatti, J.B., Schoell, M., 1981. Fractionation of carbon and hydrogen isotopes by methane oxidizing bacteria. Geochim. Cosmo- chim. Acta 45, pp. 1033-1037. Etiope, G., Panieri, G., Fattorini, D., Regoli, F., Vannoli, P., Italiano, F., Lo- Acknowledgments critani, M., Carmisciano, C., 2014. A thermogenic hydrocarbon seep in This study has been funded by the Italian Ministry of Economic Development, Directorate General for Safety – National Mining Office for Hydrocarbons and shallow Adriatic Sea (Italy): Gas origin, Georesources (DGS UNMIG) under the umbrella of the Offshore safety network, sediment contamination and benthic which is in force since 2014, and was established with bilateral agreements between foraminifera. Marine and Petroleum the Ministry and Research Centres, Governmental Bodies and Universities in or- Geology 57, pp. 283-293. der to increase the safety, also in terms of environmental protection, of offshore Hovland, M., Judd, A.G., King L.H., plants operations. The current Agreement between DGS UNMIG and CNR-IS- 1984. Characteristic features of MAR /2017-2018) is coordinated by Dr. Marzia Rovere and includes the activities pockmarks on the North Sea Floor presented in this contribution and those which fall in the SPOT project.

40 Dicembre 2017 ambiente

M. Cocuzza*,** Innovative technologies for L. Scaltrito* S. Ferrero* offshore platforms safety and S.L. Marasso*,** D. Perrone*** environmental monitoring C.F. Pirri*,***

* SEADOG – Dipartimento di Scienza Applicata e Tecnologia (DISAT) – Poli- The Oil&Gas industry features peculiar characteristics and criticalities in terms of risk assessment tecnico di Torino and management, both for the environment and for human health. The offshore framework, due to ** IMEM-CNR, Parma its unique logistics, compactness and density of installations, is a further specificity for which various *** Center for Sustainable Futures@ recommended practices and standards, constantly evolving and with significant differences depend- PoliTo, Istituto Italiano di Tecnologia, ing on the geographical scenario, are currently in use. Torino Starting from an accurate analysis of such standards and the state of the art of environmental monitoring and fire&gas alert systems, the SEADOG (Safety & Environmental Analysis Division for Oil&Gas) research center of Politecnico di Torino is developing a new generation of sensing platforms characterized by limited dimensions, optimization of energy requirements and reduced implementation costs, with the aim of improving risks control protocols by distributed plant monitoring la et al., 2014). The main task is to and the detection of chemicals that are accidentally dispersed in the sea. improve the risk control protocols through distributed offshore plant In this regard an innovative solid state sensor for H2S detection, fabricated by MEMS and micro-hotplate technology and integrating nanostructured material, and a spectrophotometric monitoring monitoring and the detection of platform for the detection of heavy metal ions in offshore installations neighboring waters will be chemicals that may be accidentally described in detail. dispersed at sea. Keywords: offshore Oil&Gas, MEMS, H2S, heavy metal ions, spectrophotometric detection. In compliance with the current legislation, with no claim to replace Tecnologie innovative per la sicurezza e il monitoraggio ambientale in ambito of- the analytical protocols practiced by fshore. L’industria Oil&Gas presenta peculiari caratteristiche e criticità in tema di valutazione e ge- certified laboratories, but with the stione del rischio, sia ambientale che per la salute umana. Il contesto offshore, in virtù della propria aim to integrate and complement particolare logistica e della compattezza e densità delle installazioni, costituisce un’ulteriore specifi- cità per la quale esistono diverse norme, standard e pratiche raccomandate, in continua evoluzione them with respect to their current li- e con sensibili differenze in funzione dello scenario geografico. mits, the development of a family of A partire da un’attenta analisi di tali normative e dello stato dell’arte dei sistemi di monitoraggio sensory platforms to be used for the ambientale e fire&gas, il Polo di Ricerca SEADOG (Safety & Environmental Analysis Division for systematic analysis of water quality Oil&Gas) del Politecnico di Torino sta svolgendo attività di sviluppo di piattaforme sensoristiche di around offshore oil platforms is cur- nuova generazione caratterizzate da limitate dimensioni, ottimizzazione dell’autonomia energetica rently on the way. The results of the e costi di implementazione ridotti, con l’obbiettivo del miglioramento dei protocolli per il controllo development of analytical systems dei rischi mediante il monitoraggio distribuito sugli impianti e per la rilevazione di sostanze chimiche based on microfluidic devices for accidentalmente disperse in mare. the detection of potential pollutants Nel presente lavoro verranno in particolare descritti gli sviluppi relativi un sensore a stato solido per accidentally released will be shown. la rivelazione di H2S, realizzato mediante tecnologia micro hotplate e integrante materiale attivo The use of such a family of devices nanostrutturato, e una piattaforma di monitoraggio delle acque limitrofe alle installazioni offshore will allow for a significant impro- per la rilevazione degli ioni metallici pesanti mediante tecnica spettrofotometrica. Parole chiave: offshore Oil&Gas, MEMS, H S, ioni metallici pesanti, rivelazione spettrofotometrica. vement in terms of process control 2 continuity, with obvious implications in particular on the quality and safety aspects of the marine en- 1. Introduction generation sensors-based monito- vironment adjacent to oil platforms. ring systems, relying on innovative As in the case of environmental The SEADOG Research Center micro and nano-scale, but robust monitoring, the results of the acti- at Politecnico di Torino is involved technologies already available at vity related to the development of in research and development acti- the Research Center (Cocuzza et al., a solid-state H2S monitoring sensor vities on safety and environmental 2012; Balma et al., 2011; Tommasi et will be reported. It is provided with monitoring for offshore hydrocar- al., 2014; Ramella et al., 2015a; Ra- innovative features compared to the bon exploration and cultivation fa- mella et al., 2015b; Bocchini et al., existing ones and it was designed cilities. Current research involves 2017; Chiolerio et al., 2013; Stassi et through the convergence of several the study and development of new al., 2012; Stassi et al., 2013; Vento- advanced technologies: (i) nano-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 41-50 41 environment technologies, for the growth of acti- undermine the detection of target maximum acceptable peak for 10 ve material sensitive to the presence gas (e.g. because of cross sensitivity minutes over the ACC for a 8 hour of target gases even at very low con- or poor specificity of the detector). shift. NIOSH (National Institute for centrations and based on semicon- The offshore environment is also Occupational Safety and Health) ducting metal oxide nanostructures characterized by a complex mix has set the IDLH concentration (Huang and Choi, 2007; Huang and of open and closed areas, low and (Immediately Dangerous to Life or Wan, 2009; Calestani et al., 2010; high level areas, extreme dangers Health) at 100 ppm (HSE, 2009). Leccardi et al., 2012) and (ii) Mi- of potentially releasable or poten- The American Petroleum Institute cro Electro Mechanical Systems tially hazardous gases, presence of (API) has fixed 10 ppm TWA (Time (MEMS) technology (Bogue, 2013; potential traps or gas storage bags, Weighted Average) and 15 ppm Tommasi et al., 2014; Marasso et al., variety of operating conditions and STEL (Short-Term Exposure Limit) 2016; Balma et al., 2011; Cocuzza et environmental factors that can af- plus the use of individual workers’ al., 2008) for the construction of the fect the reliability of gas detection means of protection (API, 1995). suspended microstructure (micro- systems. The UK’s HSE (Health and Safety membrane or micro hotplate), based H2S detection is strategically im- Executive) has also set its 8-hr TWA on an electrically and thermally in- portant for many application scena- and STEL limits to 5 and 10 ppm re- sulating material on which the abo- rios in Oil&Gas industry. Particular spectively (HSE, 2009; HSE, 2011). ve mentioned sensing material and attention is given to its intrinsic The Norwegian standard NORSOK the electronic devices for its control danger. H2S is a colorless gas, cha- S-001 (NORSOK, 2008) is recom- are integrated. racterized by a pungent odor, similar mending to set the alarm limits for to that of rotten eggs. Even at very the H2S sensing devices between 1 low concentrations it is still extre- and 20 ppm. ACGIH (American mely toxic and able to attack and Conference of Governmental In- 2. Micro hotplate sensor for inhibit the smell. In addition, un- dustrial Hygienists) recommends a H2S detection der appropriate conditions of air or TWA of 1 ppm and a STEL of 5 ppm oxygen mixing it may be explosive (ACGIH, 2012). 2.1 Offshore platform H2S (range of flammability 4.3-45.5%). In addition to health risks, the detection It dissolves in liquids and can there- structural effects of exposure of ma- fore be found in any container, tank terials and plants to H2S should also In the offshore framework, ha- or medium for liquids transport such be considered. Many materials may zardous (inflammable and/or toxic) as oil, water, fuels or emulsions. It exhibit sudden structural cracks ge- gases are naturally present and their can be found in different working nerated by a characteristic sulfide accidental release contributes signi- environments, mainly but not exclu- stress-cracking (SSC) phenomenon, ficantly to risk assessment. One of sively, those of the oil industry (refi- which, moreover, worsens with the the key points of a plan for the pre- neries, oil wells, …) and is naturally strength and tensile stress exerted. vention and reduction of risks for present along with the natural gas of The damage and wear of some com- staff and equipment is the adoption the wells. ponents in the production and proof appropriate alarm systems, such It has a wide-spectrum toxicity cessing of natural gas, if used in the as those based on flammable and effect, although the nervous system SSC regime, could cause uncontrol- toxic gas sensors. These allow to un- and cellular respiration are the first led release of H2S in the atmosphere. dertake remedies and precautionary systems to be attacked under expo- Such embrittlement is often not vi- actions to be adopted as part of a sure. H2S is toxic in the 500-1000 sually perceptible and can also evol- comprehensive, automated and in- ppm concentration range, but deve very quickly. tegrated control and security system ath is not instantaneous. However of an industrial complex. at concentrations above 1000 ppm 2.2 Semiconductive H S sensing Offshore installations have diffe- H2S is rapidly lethal (HSE, 2009; 2 rent and challenging gas detection HSE, 2011). 800 ppm is the lethal requirements, often requiring spe- concentration generally accepted for The operation of a solid-state cific solutions: e.g., some structures 50% of the population for 5 minutes sensor is based on the conducti- require gas detectors able to identify of exposure (LC50 (Lethal Concen- vity variation of a semiconductor the target’s presence at the lowest tration 50%)). element (usually a metallic oxide possible concentration (in ppm or OSHA (Occupational Safety & such as SnO2, ZnO, TiO2, WO3, % LEL (Lower Explosion Limit)), Health Administration) fixed the …) induced by adsorption of some while other services/structures may Acceptable Ceiling Concentration gases (reducing such as combusti- be exposed to gas mixtures that can (ACC) in 20 ppm and 50 ppm the ble gases or oxidants such as NO2)

42 Dicembre 2017 ambiente in contact with the porous surface 100 and 500 °C) and hence of a con- (through the sensitive film or wor- of the semiconductor electrically stant supply of energy quantifiable king temperature, for instance), thus heated at a predetermined tempe- between several hundred mW up to allowing the creation of detection rature (threshold temperature). The about 1 W. matrices that, again, may favor se- temperature of the sensitive ele- lectivity. ment (depending on the type of gas The developed H2S sensor in to be detected, sensor fabrication 2.3 Micro hotplate H2S sensor micro hotplate technology is based technology and sensitive material on a silicon microchip containing structure) is a major parameter for In order to mitigate some of the a thin (1 μm) suspended silicon both sensitivity and selectivity. The above reported limits, a micro and nitride membrane. The membrane temperature control is secured by a nano-scale manufacturing process multi-layered sandwich structure built-in heater (a thick or thin film has been developed to provide so- (buried micro hotplate) integrate all depending on the manufacturing lid state sensors based on structures the active elements (a meandering technology) integrated into the known as “micro hotplate” (Huang Ta/Pt thin film heater and tempera- sensor and a temperature monito- and Wan, 2009; Calestani et al., ture sensor and the active sensing ring system and electronic feedback 2010; Leccardi et al., 2012; Marasso material) separated each other by to keep it constant around the set et al., 2016; Tommasi et al., 2017) nanometric layers of insulating ma- point. This type of sensors can me- (Fig. 1). This term identifies a sen- terial (silicon oxide) (Tommasi et asure the concentration of different sor realized by sophisticated silicon al., 2017). The Ta/Pt resistor was de- hydrocarbons, carbon monoxide micromachining technologies (Bulk signed in order to optimize the tem- (CO), ozone (O3), H2S, volatile Micromachining or Surface Micro- perature distribution and used both organic compounds (VOCs, such as machining) that enable the active for heating the membrane and get- ethanol) and oxidizing gases such as elements of the sensor (active film of ting a temperature readout through NO2. semiconductor metal oxide, heater the calibration of the corresponding Among the main advantages of and temperature sensor) to be inte- temperature coefficient of resistance this type of sensor it is possible to grated on a suspended insulating mi- (TCR). In our case, a Ta adhesion list: (i) detection versatility (they cromembrane made of silicon oxide layer was selected since it has been are able to measure the concen- or silicon nitride. proven to perform better than the tration of different hazardous ga- The main advantages resulting usual Ti. Indeed, it shows similar ses); (ii) longest operating life time from the adoption of this techno- adhesion properties but moreover it among the available technologies logy are: (i) the reduction of the also plays an important role as a dif- on the market (life expectancy of thermal capacity of the system and fusion barrier when working at high the order of 10-12 years); (iii) robust the optimization of the thermal in- temperature to prevent unwanted and tolerant sensors under extreme sulation to the silicon substrate, re- alloy generation between Ti and Pt. environmental conditions and cor- sulting in a significant reduction in Sensitive material consists of ZnO rosive atmospheres; (iv) since ope- the energy needs to heat the sensor nanostructures (tetrapods, TPs). rating by integrated heating, they to the temperature set point (tens ZnO-TPs are nanostructures formed are relatively insensitive to ambient of mW) and faster response; (ii) the by four nanowires with a common temperature changes (can operate possibility of employing nanostruc- core and respectively oriented as the up to ambient temperatures of 90 tured (film) materials, increasing axes of a tetrahedron. Their overall °C); (v) high ambient tolerance is the active surface/inert volume ratio size, however, is generally in the also extended to relative humidity and increasing the sensitivity of the micron-scale range. ZnO TPs were conditions (ranging from 5 to 95% sensor (sensitivity below ppm); (iii) synthesized in a tubular furnace by provided not under condensation the possibility to implement rapid combining thermal evaporation and conditions). heating and cooling cycles enables controlled oxidation. A metallic Solid-state sensors, however, are the detection at variable tempera- Zn foil was used as source material, also characterized by some weaknes- ture conditions (even several detec- without any catalyst or precursor ses such as low selectivity (in parti- tion steps at different temperatures to reduce unwanted contamina- cular with respect to H2S), high cross in one second), thus modulating the tions (Calestani et al., 2010). The sensitivity to different hydrocarbons, sensitivity of the sensor to different TPs were deposited by using a top- VOCs, chlorinated gases, NOx and gases and allowing therefore to build down approach: the TPs were fir- generally high energy consumption. detection matrices that favor selec- stly dispersed in a isopropyl alcohol Indeed such types of sensors need tivity; (iv) the ability to make micro suspension and then precipitated heating of the active element at re- hot-plate arrays in which each sen- by centrifuging at 3500 rpm for 10 latively high temperatures (between sor is differentiated from the others min in order to obtain a homoge-

Dicembre 2017 43 environment

Fig. 1. From left to right: buried micro hotplate layout, silicon die and final packaged device. Da sinistra verso destra: layout della micro hotplate con struttura sepolta, chip in silicio e dispositivo finale integrato nel suo package. neous dispersion and a packed layer on the suspended membrane. The nanostructures were deposited in a limited area between the interdigi- tated sensing electrodes by aligning a clamped polydimethylsiloxane (PDMS) physical mask with a central square window. The sensor characterization demonstrates excellent sensitivity to H2S, with a maximum response around 300 °C and a Limit of De- tection (LOD) of 500 ppb (Fig. 2), which can be further improved. Like all sensors based on the same physi- Fig. 2. Sensor response values versus ethanol, carbon monoxide, methane and hydro- cal principle, there is some sensitivi- gen sulphide concentration (H2S) in air (T = 300 °C; RH = 30%). ty to other types of gas (further mea- Risposta del sensore rispetto a diverse concentrazioni in aria di etanolo, monossido di car- surements were made with exposure bonio, metano e solfuro di idrogeno (H2S) (T = 300 °C, umidità relativa = 30%). to carbon monoxide, ethanol and methane), but with a much lower le- 3. Evolved sensing platform tification, if present in the sample. vel of response than at the same con- for the offshore sites sea This kind of approach cannot be centration of H2S, with an increase exploited to implement strategies for of the sensor selectivity compared water environmental prevention of environmental disa- to the state of the art. The fact that monitoring sters and therefore, since the public different gaseous species show a dif- opinion and several international re- ferent response dependence versus 3.1 Current approach for gulations require greater attention to temperature is very important when offshore platform sea water the environment care, it is necessary the responses from sensors with dif- monitoring to evolve current monitoring systems ferent heating conditions have to be into one that can alert in real time an compared to improve the sensor se- Checking the quality of sea wa- intervention team, so to avoid pollu- lectivity and gas recognition among ter in the neighborhood of offshore tion, often irreversible, of the water. possible interfering species. oil production sites takes place every The exploitation of reservoirs, In addition, the maximum con- six months or yearly. Periodic mo- whether they are oil or gas, invol- tinuous power consumption of the nitoring is performed by collecting ves the production of waste, inclu- sensor is less than 150 mW, saving in-situ water samples that are then ding the Produced Formation Water nearly an order of magnitude com- analyzed in specialized laboratories, (PFW). PFW is the most relevant pared to commercial solutions that primarily using chromatographic or type of effluent in the production are not based on micro and nano- spectroscopic techniques for the or- phase of hydrocarbons on offshore technology approaches. ganic/inorganic contaminant iden- installations, both for the generated

44 Dicembre 2017 ambiente volumes and for the level of pollutants potentially present. Down- stream the purification treatment, the production of water for the sea discharge appears as a heterogeneous mixture, constituted by an aqueous phase with the residual solid material in suspension. The aqueous phase contains inorganic (salts, metals Fig. 3. Block diagram of the integrated environmental monitoring platform. and radioisotopes) and organic (mo- Schema a blocchi della piattaforma di monitoraggio ambientale integrata. no-compounds, polycyclic aromatic, aliphatic hydrocarbons, …) chemi- platform according to specific requi- be the frequency for sampling and cal species. rements: a first module is dedicated data acquisition, that impacts on the The proposed solution to signi- to the collection of the seawater reagent volumes and the drainage ficantly improve the operational sample (module I), the second to the tank to be integrated. No ultimate scenario and overcome the above selective separation/pre-treatment requirement has been fixed yet on mentioned current limits in terms of of the target analyte to be detected this particularly critical aspect, sin- offshore environmental monitoring (module II), a third module dedi- ce the involved project stakeholders is that of a sensing platform capable cated to the analyte measurement are still pursuing an optimal compro- of sampling at least daily (or more (module III) and a final module for mise as a function of the final real frequently as a function of the asso- the storage of the waste and/or the test scenario. A realistic estimation ciated risk analysis) the waters near storage of a “fresh” sample in case of the real sample will be of the order a site of interest, activating an ON/ of exceeding the expected warning of 100 µl. OFF procedure about the presen- thresholds (module IV) (Fig. 3). De- Since the sensing platform will be ce or absence of contaminants and pending on the specific analyte con- employed in a situation where remo- eventually preparing the collected sidered, the microfluidic subsystem te monitoring is required, it has been samples for a more accurate, quanti- will be customized to separate and/ supplied with a data transmission tative and lawful analysis in case of or pre-concentrate and/or pretreat system as Ethernet / WiFi / GSM so activated alarm. The design of the the analyte, preparing it for the next that the sampled data and the ope- platform takes advantage of micro- analytical phase based on spectro- rating state of the sensing platform fluidic (Lab-On-Chip) technologies photometric detection. The plat- (failure, alarm, maintenance re- (Wu and Gu, 2011; Gupta et al., form must also perform an automatic quest, exhaustion of reagents, filling 2016; Jang et al., 2011; Marasso et al., cleaning step of the measuring cells of waste, etc.) can be collected, ma- 2008; Potrich et al., 2014; Marasso et after each measuring cycle. nipulated and stored. al., 2014; Chen et al., 2012) for the A remarkable parameter to di- Figure 4 shows the platform as- management of the fluids and the in- mension the sensing platform will sembly, with the main subsystems situ analysis of marine sample. This approach will involve a dramatic reduction of the sample and reagents volumes, a prolonged monitoring and a greater time and space coverage around offshore platforms without a noticeable loss of performance in terms of sensitivity.

3.2 Design of the evolved sensing platform for heavy metals detection

To ensure greater versatility, the sensing platform was conceived as 4 main independent modules (each Fig. 4. Design of the AUV-ready payload hosting the sensing platform. separately powered and controlled), Schema del payload predisposto all’installazione su AUV ospitante la piattaforma di moni- but integrated so as to customize the toraggio ambientale.

Dicembre 2017 45 environment labeled, inside a sailing payload rea- sions and losses in the twenty years regard, Trabucco et al. (2008) studied dy to be connected to a commercial following the adoption of measures the accumulation of heavy metals in Autonomous Underwater Vehicle for this purpose. Priority Substances mussels located near a gas platform (AUV). under Review (PSR), which may, if installed in the Central Adriatic. further investigation justifies it, be Transplanted organisms possess hi- proposed as PHS. The third category gher concentrations of cadmium and 3.3 Heavy metal ions detection is that of Priority Substances (PS), zinc than the organisms maintained case study which must be subject to progressive in the control areas. reduction of emissions and losses in The heavy metal ions monitoring Notwithstanding the concept the environment. The Priority List platform under development is ba- of modularity and versatility of the contains 33 substances. Among the- sed on an absorption spectrophoto- monitoring platform and the possi- se, two heavy metals appear among metry detection technique in the ul- bility of replacement/extension of the PHS (cadmium, mercury and tra-violet (UV) and visible regions, modules dedicated to the detection their compounds), one among the with the help, for the latter, of a of other contaminants in later con- PSR (lead and its compounds) and complex type separation method for figurations, the current development one among PS (nickel and its com- each analyte. The several detection of the sensing platform has been fo- pounds). In 2013, a new Directive, subsystems (optical source, detector, cused on a heavy metal ions demon- 2013/39/EC (EU, 2013), amended optics) are adaptable and reconfi- strator (zinc, chromium, nickel, cop- the Directive 2000/60/EC as regards gurable to optimize the detection per, cadmium, mercury, arsenic…). priority substances in the field of wa- of specific analytes or sets of them. Heavy metals accumulate throu- ter policy. Newly identified substan- The tool also has the same versati- gh the food chain and can pose a ces were added, including the setting lity as regards the mechanical, flu- threat to the species at the top of it, of environmental quality standards id and data exploitation aspects of including man. The major issue is (EQS). the sample, namely the volume of that, moving from a trophic level to The potential environmental risk samples to be analyzed, the sam- the next, the amount of accumula- represented by PFWs should be ad- pling system and the management ted toxic substance increases more ded to the one introduced by the use of raw data acquired. These latter and more. In this way the predatory of sludge and drilling fluids. Water- can be stored on-board or real-time organisms at the top of the large food based perforating sludge is not simply transmitted via Ethernet / WiFi / chains (tons, sharks, dolphins and made up of “biodegradable” material GSM communication to a deloca- ultimately man) are also the most but is mainly composed of bento- lized central server with dedicated exposed to the risk of serious intoxi- nite clay, barium sulphate, calcium software, where data analysis can be cation. This phenomenon is called carbonate, hematite. Some of these performed later. The entire system is bioaccumulation or biomagnifica- substances are toxic to marine life, managed by a dedicated microcon- tion. especially when mixed with gaseous troller control unit that can execute The European Water Policy Stra- and fluid waste during well drilling, the operating sequence, capture the tegy has undergone a process of pro- or as a result of chemical reactions measurement data, perform a multi- found restructuring and the Water that normally develop during dril- variate analysis, and send the result Framework Directive 2000/60/EC ling. According to the EPA (Envi- remotely. (EU, 2000) has become the opera- romental Protection Agency) of the As regards the spectrophotome- tional instrument to fix the targets United States of America, in perfo- tric approach, it measures the ab- for future water protection. The rating fluids very often there is the sorbance of a light beam that crosses Water Framework Directive has pro- presence of heavy metals and other an optical path with a fixed volume duced a list of “priority substances hazardous substances such as mercu- where the analyte to be detected selected among those posing a signi- ry (mixed species to barite), arsenic, containing solution is present. It is ficant risk for or through the aquatic vanadium, lead, zinc, aluminum, therefore necessary to provide mi- environment” (Priority List). This chromium and BTEX (benzene, to- crofluidic chambers consisting of list is based on toxicity, persistence, luene, ethylbenzene and xylene). capillaries in which the liquid to be bioaccumulation potential and risk In addition, underground drilling is analyzed is inserted and whose extre- to human health. Within the prio- almost always accompanied by the mities are exposed to optic windows rity list there are three categories of production of water mixed to mi- for the optical probe and the detec- substances. Priority Hazardous Sub- neral oils containing further pollution of the optical signal transmitted stances (PHS) are considered those tants, including barium, beryllium, by the sample, depending on the for which there must be a gradual cadmium, chromium, copper, iron, length of the optical path; Beer’s law cancellation of discharges, emis- lead, nickel, silver and zinc. In this (1) provides a correlation of the op-

46 Dicembre 2017 ambiente tical signal with the concentration per concentration in aqueous solu- minates the interference of other of the species to be detected: tions can be carried out by adding metals. The reading is performed at complexes such as oxalidihydrazide a wavelength of 650 nm with a de- A = ελ · l · M (1) (CONHNH2)2 and acetaldehyde tection range between 0.02 and 2.0 where A = absorbance; ελ = molar (CH3CHO) at pH 9.3 to provide a mg/L. extinction; l = geometrical path; highly stable intense violet complex Multivariate analysis allows the M = molar concentration. whose absorbance is measured at 540 analysis of complex matrices where The detection of heavy metal nm. This method can be applied to there is a strong variability of input ions by spectrophotometry involves natural waters (including marine if data (Ghasemi et al., 2003). In this the detection of single elements or concentration levels permit) and case, the PCA (Principal Compo- composites, also called single track, waste waters in the concentration nent Analysis) was used to deter- or the simultaneous detection of range between 0.05 and 0.50 mg/L. mine the number of components multiple elements or composites A method for determining nickel that describe the water matrix. PCA using multivariate analysis. Particu- is the reaction between nickel ions plans to create new variables, called larly heavy metal ions such as chro- and dimethylglyoxime (C4H8N2O2). principle components (PCs), which mium, copper, nickel and zinc have The reaction is carried out in the describe most of the variability of been analyzed. presence of an oxidizing agent to data. This allows the samples to be Chromium in its hexavalent form obtain a soluble chelated red-wine described with a considerably redu- is more eco-toxicological than the or brown (depending on the condi- ced amount of variables compared to trivalent. The spectrophotometric tions of formation) complex. Am- those initially present. The first PC detection method is based on the monium citrate provides metal ion is the direction that describes most color development resulting from complexation in ammoniacal alka- of the data variability. The second the reaction between hexavalent line (pH 11-12) conditions. The PC, and the following, must be or- chromium and diphenylcarbazide photometric reading is carried out thogonal to the former and describe (C12H13N4O) and the mechanism of at a wavelength of 470 nm and the the maximum amount of remaining this reaction consists in a reduction normally detectable range is betwe- variability. Once directions of PCs of Cr VI to Cr III and at the same en 0.05 and 5.0 mg/L. are known, we can express the va- time oxidation of diphenylcarbazi- As for Zinc, one of the most com- lues of absorbance of each sample as de to diphenylcarbazone, resulting monly used procedures involves the a sum of the original data multiplied in formation of a colorful red-violet use of Zincon® (monosodium salt of by a coefficient describing the PCs. complex. Cr VI is determined by ab- 2-[α-(2-hydroxy-5-sulfophenylazo) These new values are known as “sco- sorbance measurements allowing the benzylidene]-hydrazine)-benzate) res” and each sample (in this case determination of only hexavalent organic complexing agent. This pro- any unknown sample analyte with chromium directly in the aqueous cedure is based on the formation of the corresponding absorbance spec- sample, in the concentration range the blue Zn/Zincon® complex in trum) has a “score” for each PC (the between 0.05 and 1 mg/L (ppm). buffered environment at pH 9. The same as it has a value for each varia- The determination of the cop- addition of sodium thiosulphate eli- ble, in our case wavelength, in the

Fig. 5. Absorption spectra of samples with different.Cr VI concentrations normalized with respect to a reference sample (left) and correlation between relative intensity measurements at 371 nm and Cr VI concentration (right). Spettri di assorbimento di campioni a diverse concentrazioni di Cr VI normalizzati rispetto ad un campione di riferimento (sinistra) e correlazione fra misure di intensità relativa a 371 nm e concentrazione di Cr VI (destra).

Dicembre 2017 47 environment original data). Multivariate analysis the feasibility of a spectrophotome- micro-hotplate technology and in- requires a fairly high number of sam- tric approach based sensory platform tegrating nanostructured active ma- ples to be analyzed. Once the num- for the simultaneous determination terial, and a monitoring platform for ber of PCs needed to describe the of copper, zinc and nickel in sea wa- offshore facilities neighboring water spectrum of water matrices and the ter surrounding offshore plants. It for heavy metal ions detection by ion metal content of each sample is obviously a demonstrator of such spectrophotometric technique. is known, it is possible to apply the feasibility, so the extension of the H2S sensors provided with relati- partial least squares (PLS) regression detection technique to other heavy vely large ZnO nanostructures, like method to try to model the system so metal ions (Hg and Cd in particu- ZnO-TPs, on a micro-hotplate were as to predict the ion metal content lar) and other dangerous substan- fabricated by combining MEMS on the basis of UV-visible spectra ces (benzene, toluene and aliphatic technology and an innovative in- (Ghasemi et al., 2003). hydrocarbons in particular) is cur- tegration process based on centri- The employed protocol invol- rently under development. fugation of nanostructures suspen- ves the use of a Zincon® solution, sions. The designed micro hotplate a characteristic zinc complexing produced the correct nanostructure agent, which also forms complexes heating, was proven to be robust with copper, cobalt and nickel. The 4. Conclusions enough for the dedicated task and absorption spectra of Zincon, Zn- to have stable electrical performan- Zincon, Cu-Zincon and Ni-Zincon The SEADOG Research Center ce in time. The porous active film complexes appear very different, but is engaged in research and deve- made of ZnO-TPs showed excellent the presence of overlapping areas lopment activities for the adoption adhesion and very good sensing pro- does not permit the determination of new safety-oriented and envi- perties with low concentrations of of the concentration of the different ronmental monitoring technologies H2S. The produced sensors have gre- metals based on the absorbance va- for offshore hydrocarbon explora- at performances, at least comparable lue at a single wavelength. Multi- tion and cultivation facilities. A spe- (in some cases better) with those of variate analysis methods were then cific section of the Center deals with previously reported sensor protot- used to obtain an analytical method the experimental development of ypes and commercial devices. Mo- for zinc, copper and nickel analysis. environmental monitoring systems reover, all the described procedures Figure 6 shows the observed data and new generation fire&gas sen- can be easily scaled to a large-scale (actual concentration) compared to sors. The main objective is to impro- wafer level production in order to the values obtained from the model ve the risk control protocols through fabricate hundreds of sensors at one (predicted concentration). It can be distributed plant monitoring and the time. observed that there is a good agre- detection of chemicals that may be Furthermore, a spectrophotome- ement between experimental data accidentally dispersed at sea. tric detection of heavy metal ions and data obtained with the mo- In particular, two case studies are implemented on a microfluidic plat- del (the maximum deviation is 0.2 being finalized: a solid-state sen- form has been developed. Such in- ppm). This result allows establishing sor for H2S detection, made using novation will allow the possibility

Fig. 6. Correlation between predicted (from the model) and actual concentration of Zn (left) and Cu (right). Correlazione fra la concentrazione prevista dal modello e quella misurata su campioni reali a diverse concentrazioni di Zn (sinistra) e rame (destra).

48 Dicembre 2017 ambiente of extending the analysis method Sensor Review, Vol. 33 (4), pp. licy, Official Journal of the Europe- and its implementation on AUVs 300-304. an Union, L 226/1, 24/8/2013, pp. or delocalized in different envi- Calestani, D., Zha, M., Mosca, R., Zap- 0001-0017. ronmental monitoring application pettini, A., Carotta, M.C., Di Natale, Ghasemi, J., Ahmadia, Sh., Torkestani, frameworks. Thanks to its modular M.C. and Zanotti, L., 2010. Growth K., 2003. Simultaneous determina- structure, the monitoring platform of ZnO tetrapods for nanostructure- tion of copper, nickel, cobalt and zinc will be customizable with respect to based gas sensors, Sensors and Ac- using zincon as a metallochromic specific analytes and expandable for tuators B: Chemical, Vol. 144 (2), indicator with partial least squares, multi-parametric sensing. Benefits pp. 472-478. 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Acknowledgements This paper would not have been possible without the sponsorship of the Mini- stry of Economic Development’s Directorate General for Safety – National Mining Office for Hydrocarbons and Georesources. In particular, authors would like to express their gratitude to the people who have supported this work along all the stages of its realization.

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G. Agate* Numerical approach R. Guandalini* to simulate the sea oil F. Moia* * Ricerca sul Sistema Energetico – dispersion related to a RSE S.p.A., Milan, Italy hypothetical accident scenarios by following the evolution of the phenomena involved both This study describes the use of the methodology developed to evaluate the dynamics related to the in time and space and carrying out dispersion of hydrocarbons in the sea and the related environmental impact. Different hypothetical design checks by evaluating the ef- spill scenarios due to platform or floating vessel accidents has been analyzed, in particular a serious fectiveness of suggested prevention accident event (strong intensity for a short time) has been considered. The applied 3D numerical or recovery actions, also considering model was able to consider the complexity of the sea system involved in the dispersion process (e.g. meteorology, marine and morphological conditions) highlighting the ability to reproduce the spread the local meteorological, marine of hydrocarbons in the sea and demonstrating that the model is capable of supporting verification and morphological conditions. The requirements, in terms of environmental safety, of oil exploitation projects. software used, based on the integra- Keywords: 3D fluid-dynamic model; oil spill; hydrocarbons; off-shore platform; Oil&Gas platforms. ted HyperSuite simulation system (Guandalini, Agate, 2017b), takes Approccio numerico per simulare la dispersione di idrocarburi in mare dovuta a un into account various parameters ipotetico incidente. Lo studio descrive l’utilizzo della metodologia sviluppata per la valutazione such as the current field of the sea delle dinamiche legate alla dispersione degli idrocarburi in mare e al conseguente impatto ambien- and its turbulence, the wind acting tale. Sono stati analizzati diversi scenari ipotetici di sversamento aventi come fonte di emissione on the surface of the sea, the sali- piattaforme o serbatoi galleggianti, in particolare è stato considerato un evento di incidente grave nity and temperature, local coastal di forte intensità e breve durata. Il modello numerico 3D applicato è stato in grado di tenere conto morphology, bathymetry of the sea della complessità del sistema marino coinvolto nel processo di dispersione (meteorologia, condizioni and the tide. The fluid dynamic mo- marine e morfologiche) evidenziando la capacità di riprodurre la diffusione di idrocarburi in mare e dimostrando che il modello è in grado di supportare le esigenze di verifica nell’ambito della sicurez- del is based on a 3D Eulerian finite za ambientale dei progetti di produzione petrolifera. element type where the accuracy is Parole chiave: modelli fluidodinamici 3D; sversamento petrolio in mare; idrocarburi; piattaforme guaranteed by a very detailed spatial off-shore; piattaforme Oil&Gas. mesh. It solves RANS equations for uncompressible fluids considering the sea water and solving coupled flow and transport processes of the 1. Introduction 1.1. General aspects oil, in transient conditions. The 3D numeric model has been applied to In the frame of a big research In this study, a 3D numerical ap- hypothetical oil spill scenarios whe- project, funded by MISE DGS- proach for the analysis of oil disper- re release sources are due to platform UNIMIG (the Italian Ministry of sion in the sea was used in order to incidents or floating ships (FPSOs). Economic Development, Directo- simulate with a high level of accu- The assumed scenario is located in rate General for Safety – National racy the dynamic behavior of the the North of the Adriatic Sea of- Mining Office for Hydrocarbons oil plume and its displacement in fshore (Italy) and the first step was and Georesources), concerning the the environment (Guandalini, Aga- in a preliminary numerical simula- safety of offshore plants according te, 2017a). To carry out this type of tion of unperturbed fluid dynamic to the Italian Legislative Decree analysis, characterized by a high de- sea conditions at its starting date; n.83 (June, 26 2012) (MISE, 2014), gree of complexity and which can the second step was the oil plume RSE has carried out a specific rese- consider different scenarios both by displacement simulation during the arch activity on the use of 3D nu- type of accident and by intensity of considered emission period. merical approach for the analysis of spillage and with phenomena oc- The results allowed to evaluate oil dispersion in the sea, in order to curring over several days, the only the relevance of the effects of all the simulate with a high level of accu- approach currently usable, both in environmental parameters such as racy the dynamic behavior of the terms of response time and in terms wind, sea current and tide, highligh- oil plume and its displacement in of cost, is the numerical simulation. ting the ability of the methodology the environment. In fact, it allows detailed analysis of to support the safety requirements

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 51-57 51 environment for offshore exploitation, provided average distance travelled by flu- – the analysis of the results, also by that a dynamic characterization of id lumps involved in the turbulent means of graphic 3D advanced the environmental parameters are mixing process, and evaluating the tools. available with a sufficient detail. It is mass exchange on the base of the It is very important to have de- important to note that the scenario Schmidt number (Welty, 1969) and tailed information about spatial and considered in this study is only a de- the heat exchange on the base of time environmental data and to pro- monstration case and that the values the Prandtl (Kays, 2005) number. perly refine the computational grid, used for the emission phase are based In order to account for the effect in order to obtain results with a high on theoretical hypotheses since in of buoyancy on turbulent flows, the level of accuracy. the past no real accident occurred in Monin-Obukhov or the Keyps rela- In the frame of this study, the de- the Adriatic Sea. tionship is used in case of stable or scribed numerical methodology has unstable stratification respectively been applied to the area located in (Monin, Obukhov, 1954). As re- the North Adriatic Sea and a hypo- gards the stress calculation on the thetical oil spill point located at a di- 2. Short description of bottom or walls, a slip or no-slip stance of about 60 km from the coast mathematical model condition can be considered. As near the sea surface has been consi- regards the numerical solution tech- dered as illustrated in Figure 1 (left). The module HYPER3D inclu- nique, the Navier-Stokes equations ded in HyperSuite software system coupled with the free surface equa- is a 3D fluid dynamic simulator ba- tion are solved for each time step 3.1. The data collection sed on finite element method able applying the fractional step method. to estimate motion and scalar fields More precisely, the horizontal velo- The collection of the envi- starting from assigned initial and city, free surface elevation and scalar ronmental and morphological data boundary conditions, taking also equations are solved using a one- include the meteorological and ma- into account for wind effects, ther- step implicit approach for the time rine data that show high variability mal exchange with the atmosphere, discretization, while the convecti- in space and time. It is essential to and tide. The mathematical model is ve terms are treated with an origi- consider these data exactly referred based on a 3D hexahedral finite ele- nal upwind technique based on the to the starting date and simulated ment mesh, automatically created spatial shift of the shape functions. period of the scenario. The typo- from the bathymetry, and it is able to Finally, the pressure and continuity logy of data that must be collected describe complex domains including equations are solved by a trapezoidal concern the morphology of the co- solid structures, irregular coastline integration along the z axis in corre- ast, the bathymetry of the seabed, and steep seabed, solving a system of spondence of each node of the finite the sea temperature, salinity and equations that includes (Guandali- element mesh. current field (both in intensity and ni, Agate, 2017a): direction), the tide level and the – the Reynolds Averaged Navier- wind field (both in intensity and di- Stokes equations for uncompres- rection). sible fluids with the hydrostatic 3.The 3D fluid dynamic As regards the morphology of approximation (Batchelor, 2000); model the coast in the area considered, – the free surface equation; that also defines the boundary of – the temperature field equation, In order to properly apply the 3D the domain, the WebGIS Tritone accounting also for temperature numerical methodology for the stu- (RSE Tritone [1]) has been used ex- stratification effects; dy of oil spill scenario, the following tracting the information about the – the salinity field equation ac- steps must be done: seabed, coast line and possible solid counting for the salt solubility; – the collection of topological, we- structures present in the area. While – the pollutant equation that consi- ather and sea data; about the bathymetry data, the in- ders the mass transport, the solu- – the creation of the computational formation drawn from WebGIS Tri- bility term and the loss of volatile grid; tone has been integrated with data fraction but not the chemical re- – the numerical simulation of the available on the European Marine actions. natural unperturbed conditions; Observation and Data network site The model includes also the state – the definition of the oil spill sce- (EMODnet [2]), characterized by equations for fluid density, diffusivi- narios; a grid size of about 230 m (1/8 arc ty and turbulent viscosity. The tur- – the execution of the transient minute). The Figure 1 (right) shows bulence is taken into account using simulations starting from the un- the resulting bathymetry as visuali- the mixing length approach, i.e. the perturbed condition; zed in the GIS environment.

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Fig. 1. Scenario #1. Area considered in the fluid dynamic model (source Google) (left). European Marine Observation and Data Network (EMODnet). Bathymetry data for the seabed reproduction (right). Scenario #1. Area considerata con il modello fluidodinamico (fonte Google) (sinistra). European Marine Observation and Data Network (EMODnet). Dati batimetrici estratti per la ricostruzione del fondale marino (destra).

The information about sea tem- the assigned time period, on a spatial information available from stations perature, sea salinity and sea current square grid of 6-7 km (1/16°) and for of the Italian National Tide Gauge field, has been extracted from the 14 vertical layers for a total depth of Network RMN [4] has been consi- CMEMS database [3] that provides about 66 m. In Figure 2 an example dered (Figure 3 (left)), but, as they information having the variability of temperature, salinity and current are referred to a specific geographic both in space and time necessary fields monthly averaged on summer location and their number is not suf- to the analyses. In fact the data are is shown. ficient to cover the area of interest, available, for the whole site and for As regards the wind field, public the meteorological model RAMS

Fig. 2. Marine current (left), Salinity (middle), temperature (right) maps in September 2014 (source CMEMS). Mappe di corrente marina (sinistra), Salinità (centro), temperatura (destra) in Settembre 2014 (fonte CMEMS).

Fig. 3. Ancona Station. Average summer wind rose (left). Sea tide evolution in September 2014 (right). Stazione di Ancona. Rosa dei venti media estiva (sinistra). Andamento della marea nel Settembre 2014 (destra).

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Fig. 4. 3D computational grid and bathymetry depth: top view (left) and bottom view (right). Griglia di calcolo 3D e mappa delle profondità: vista dall’alto (sinistra) e vista dal basso (destra).

– Regional Atmospheric Modeling during a summer season for the An- reproduced by a module included in System (Pielke et al., 1992) based on cona station closest to the boundary the software itself starting from the a global model (Integrated Forecast of the domain is shown in Figure 3 bathymetry data collected. The free System) has been used. It is able to (right). surface is discretized in the first lay- generate a wind field hourly on a grid er of the mesh as the mean sea level size of 5×5 km up to an elevation of at initial time of the simulation, wi- 10 m; an example of a wind field ge- 3.2. The 3D grid generation thout considering the air above. The nerated by RAMS is shown in Figure tidal effects are taken into account 5 (left). The next step to complete the varying the height of the first lay- Finally the sea level evolution in model is to generate the computa- er of the mesh. The final grid with time due to the tide information, tional grid taking into account the a total of about 180000 elements that can affect the surface motion morphology and the bathymetry in- and 200000 computational nodes field and consequently the plume di- formation collected in the previous has been generated. Some grid re- splacement, are available from RMN step. At first the boundaries and the finements have been done in order [4], provided by a set of 59 harmonic extension of the domain must be to describe with high accuracy the components that can be directly ac- defined, than the 3D grid is created morphology and the bathymetry in quired by the fluid dynamic simula- using hexahedral finite elements the domain, without observing si- tor. An example of tide level in time and considering the bottom surface gnificant differences on the results.

Fig. 5. Natural unperturbed conditions: Wind field from RAMS (left); sea current field on surface (center); sea current field near the platform (right). Stato naturale imperturbato. Campo di vento da RAMS (sinistra); campo di moto in superficie (centro); particolare del campo di moto intorno alla piattaforma (destra).

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To complete the model, the lateral face and near the sea bottom; sequence shows that the oil plu- surface boundary of the domain, – emission duration, flow rate and me extension spreads according to the coastline, the free surface and characteristics of the oil spilled; the main direction of the wind and the bottom surface together with – weather and sea conditions varia- the sea current circulation detected the source of emission have been ble in space and time, applied as for the reference period (Septem- labelled in order to associate the constraints on the boundaries. ber 15-25, 2015). Since the surface proper boundary conditions during In particular, in this study is de- emission is strongly dependent on the simulations. The Figure 4 shows scribed only one oil spill scenario the action of wind and surface sea the 3D computational grid and the that considers summer conditions current, the consideration of a wind depth of the sea. and the emission for a short period and current fields extremely detailed located near the surface. The mari- in time and space, as foreseen by the ne gas oil considered has density of first step of the methodology, allows 3.3. The natural unperturbed 860 kg/m3 and kinematic viscosity to follow the oil displacement beha- condition of 6*10-6 m2/s. The total simulated vior with a high level of accuracy. period is of 10 days, beginning the Starting from one day after the end Before the simulation of the 15/09/2015 at 11:00 hours, with of emission, the diffusion, not more oil spill scenario, it is necessary to the emission event occurring on fed by the source, carries out to a di- obtain the real unperturbed dyna- 16/09/2015 at 11:00 hours. The si- lution of the oil in the sea water. The mic status of the sea at the begin- mulated transient includes an initial figures show the three-dimensional ning of the simulation. In order to simulation interval of 1 day before shape of the oil plume due to the get this condition, starting from a the start of emission and in this pe- motion field action that occurs in no motion guess condition, a pseu- riod the environmental forcing para- the first instants and the successive do transient simulation has been meters as the tide level, the sea cur- dilution. performed, applying the boundary rent conditions and the wind field constraints and the wind field at the are variable with proper time laws. initial time of the scenario and ke- This approach allows having at the 3.6. The methodology features eping them unchanged until a state time of initial oil release a simulated in the frame of oil spill studies of thermodynamic equilibrium is dynamic system as close as possible reached. The result of this simula- to the real sea status at the date and The analysis of the results obtai- tion represents the initial condi- time assumed for the oil spill event. ned by the developed methodology tions for the oil spill scenario simu- The scenario considers an accident shows that it is able to describe oil lation at t = 0s. An example of the event with 1 hour emission of mari- spill scenarios with a good degree of wind field in a summer period ap- ne gas oil and spill source near the accuracy. There are other software, plied, the surface equilibrium mo- surface with a flow rate of 391 m3/h. often based on a Lagrangian appro- tion field and a detail of the surface At the end of the emission period, ach (Atle, 2017, Aamo, et al., 1995, equilibrium motion field near the the simulation continues until the Berry, et al., 2009, MITgcm), that emission source are shown in Figu- 10th day in order to account for the are commonly used in the frame of re 5. The simulation in this phase diffusion processes due to the effect the oil spill studies by the stakehol- required a computational time of of the motion field depending on ders with the aim of optimizing the 48 hours on a computer with single the environmental conditions. The mitigation of the event consequen- CPU and 8 GB of RAM. numerical simulation required a ces. The developed methodology is computational time of 15 days on a a synergistic tool able to investigate computer with single CPU and 8 GB those aspects that cannot be exploi- 3.4. The oil spill scenario of memory. ted by a different approach with the same degree of accuracy, as those A number of different scenarios due to small isles, dynamic stratifica- of oil emission have been conside- 3.5. Results analysis tion and coastal structures together red starting from the natural ther- with the consideration of the three- modynamic equilibrium state pre- The oil plume displacement at sea dimensional approach coupled flow viously evaluated and taking into surface during the simulated period and oil transport. For this reason, account the following aspects: is summarized at significant times a number of simulations, together – type of event: loss event (long pe- in Figure 6 together with the corre- with this study, that consider diffe- riod) and accident event (short sponding surface sea current fields, rent spill conditions are in progress period); considering time sequences at 24, in cooperation with the stakeholders – emission source location: on sur- 40, 52, 88, 130 and 146 hours. The themselves.

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Fig. 6. Time sequences after 1, 12, 24, 36, 48 and 72 hours after the end of emission: 3D Oil plume displacement and sea current field on surface. Sequenza temporale dopo 1, 12, 24, 36, 48 e 72 ore dalla fine dell’emissione. Configurazione 3D della macchia di olio e campo di moto in superficie.

4. Conclusions the absolute necessity of collecting small scale and the diffusion effects at the corresponding information with large scale, also providing indications The result analysis of the scena- high level of accuracy, both in space about the evolution of possible emis- rio considered, in terms of oil spill and time. sion of crude oil or marine gas oil. simulation, has shown at first that From the methodology point of during the emission period, the vor- view, the used simulation approach ticity, due to the current and wind has been able to support the safety fields and the buoyancy depending requirements of offshore oil exploi- References on the oil density, affect the oil con- tation projects in terms of envi- centration in the surface layer and ronmental impacts, provided that an Aamo, O.M., Reed, M., Downing, K., the amount of entrapment in the accurate characterization of the site 1995. Oil spill contingency and re- water column. Besides this, it has and the real conditions of the event sponse (OSCAR) model system: been found that the displacement emission together with an accurate sensitivity studies, 1995 Oil Spill is strongly affected also by the local and complete environmental data Conference. American Petroleum 3D current circulation. In any case, collection, are satisfied. Institute, pp. 429-438. the results have pointed out the re- Finally, it is important to notice Atle, K., 2017. OSCAR – Oil Spill Con- levance of the effects due to the en- that the methodology used allows tingency and Response, SINTEF, vironmental parameters as wind, sea to have a model that is able to take https://www.sintef.no/en/softwa- current and tide, putting in evidence into account both the local effects at re/oscar/

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Batchelor, G.K. 2000. An Introduction Welty, J.R., Wicks, C.E., Wilson, R.E. and Data Network, http://www. to Fluid Dynamics. New York: Cam- 1969. Fundamentals of momen- emodnet.eu/ bridge University Press. ISBN 978- tum, heat, and mass transfer John [3] Copernicus: marine environment 0-521-66396-0. Wiley & Sons, Inc. ISBN-13 978- monitoring service providing pro- Berry, A., Dabrowsky, T., Lyons, K., 0470128688 ducts and services for all marine 2009. The oil spill model OIL- applications – http://marine.co- TRANS and its application to the pernicus.eu/ Celtic Sea, DOI: 10.1016/j.mar- Websites accessed on date [4] ISPRA. Italian National Institute polbul.2012.07.036 August, 16 2017 for Environmental Protection and Guandalini, R., Agate, G., 2017a. Studio Research – Italian national tide degli effetti ambientali e della dina- [1] Tritone. http://map.rse-web.it/tri- gauge network (Rete Mareogra- mica di dispersione di inquinanti in tone/map.phtml fica Nazionale – RMN), http:// mare. Censimento sugli incidenti con [2] European Marine Observation www.idromare.it/reti_rmn.php sversamento di idrocarburi e modellazione numerica di scenari incidentali. Rapporto preliminare – Prot. RSE 17002732 (20 March 2017) in Italian Guandalini, R., Agate, G., 2017b. HyperSuite – Integrated System for Pollution and Environmental Fluid Dynamics. Hyper3D: 3D Simulator for Pollution and Environmental Flu- id Dynamic Analyses Release 6.0.7 Work note 022/2 RSE S.p.A. (In- ternal document) Kays, W., Crawford, M., Weigand, B. 2005. Convective Heat and Mass Transfer, Fourth Edition. McGraw- Hill. ISBN 978-0-07-246876-2. Ministry of Economic Development. Directorate General for Safety – National Mining Office for Hydro- carbons and Georesources 2014. Executive Act in implementation of the Agreement of Cooperation between MISE-DGRME and RSE year 2014 – Prot. RSE 15000356 (20 November 2014) in Italian MITgcm – Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Monin, A.S., Obukhov, A.M., 1954. Ba- sic laws of turbulent mixing in the surface layer of the atmosphere. Tr. Akad. Nauk. SSSR Geophiz. Inst. 24 (151): 163-187. Pielke, R.A., Cotton, W.R., Walko, R.L., Tremback, C.J., Lyons, W.A., Gras- so, L.D., Nicholls, M.E., Moran, M.D., Wesley, D.A., Lee, T.J., Copeland, J.H., 1992. A Comprehensive Meteo- Acknowledgement rological Modeling System – RAMS. Financial support from the Italian Ministry of Economic Development Meteorology and Atmospheric DGS-UNMIG under the project “safety of offshore plants” is gratefully acknowl- Physics, 49. 69-91. edged

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A. Carpignano* Modelling of a supersonic T. Corti* accidental release in Oil&Gas A.C. Uggenti* R. Gerboni* offshore: characterisation of * Politecnico di Torino DENERG, a source box Torino, Italy

The Oil&Gas offshore installations context is characterised by limited and congested spaces and, through probabilistic analyses) and because of this reason, consequences assessment, which plays a fundamental role in the definition the damages of the potential hazar- of safety barriers, poses complex modelling challenges. dous scenario (evaluated by both qua- During the early stages of the platform design, mono-dimensional or semi-empirical models are mostly litative and quantitative methods). used in industrial applications because of their simple and rapid implementation; nonetheless, they do In the Oil&Gas (O&G) sector, not gather the peculiar geometry of spaces and their lack of accuracy often brings to risk overestima- the necessity of continuously ensu- tion, hence materials and economical wastes. Besides, the safety solutions adopted in the conventional ring the operators safety and the en- industrial installations, such as the increase of distances among critical equipment, are not viable in vironment safeguard, notwithstan- the offshore context. Computational Fluid Dynamics (CFD) models can accurately simulate accidents evolutions but require a computational effort incompatible with the early design phase time schedule. ding activities that are hazardous due This work proposes a hybrid solution targeted to be a compromise between the empirical and the to the constant presence of pressuri- CFD models, splitting the accident evolution in two parts, of which the first one is replaced by a zed, flammable and toxic substances, “source box” suitably chosen while the second one is CFD modelled in order to reduce the compu- makes the field of consequences eva- tational time while maintaining a good accuracy. luation of crucial importance since The purpose of this work is the description of the source box and its characterization through the the very preliminary design of plants. main variables involved in the release phenomenon and their value ranges. Offshore platforms, although va- A case study is also presented to validate the representativeness of the chosen model. Keywords: CFD, supersonic releases, dispersion, source box, offshore platforms, risk analysis. rious in size and deployment, have common structural features. They Modellazione CFD di un rilascio supersonico accidentale in ambito Oil&Gas off- are composed of decks, hosting dif- shore: caratterizzazione di una source box. Il contesto delle installazioni Oil&Gas offshore ferent equipment dedicated to the è caratterizzato da spazi limitati e congestionati e, anche per questa ragione, l’analisi delle con- steps of the hydrocarbon extraction seguenze, che gioca un ruolo fondamentale per la definizione delle barriere di sicurezza, propone process and premises for personnel sfide modellistiche complesse. accommodation, and they are sepa- Durante le prime fasi della progettazione delle piattaforme, così come in molti altri ambiti industriali, vengono applicati modelli semi-empirici o modelli monodimensionali, anche grazie alla loro rated via floors which can be grated semplicità e rapidità di implementazione; tuttavia, questi modelli non gestiscono bene la geometria or laminated. This difference, of degli spazi e la loro scarsa accuratezza spesso porta a sovrastime dei rischi e, quindi, a sprechi di course, greatly influences the disper- materiale ed economici. Inoltre, le soluzioni per garantire la sicurezza adottate in ambiti industriali sion behaviour in case of a release. convenzionali, come l’aumento delle distanze fra apparecchiature critiche, non sono applicabili in The most frequent equipment that ambito offshore. I modelli CFD (Computational Fluid Dynamics) possono, invece, simulare accurata- constitute the internal structure of mente l’evoluzione degli incidenti e la geometria del contesto, ma richiedono un impegno computa- each deck are vessels dedicated to zionale incompatibile con i tempi delle prime fasi di progetto. separation, compression and other Questo lavoro propone una soluzione ibrida che individua un compromesso fra i modelli empirici e CFD, dividendo il fenomeno dei rilasci accidentali in due parti, delle quali la prima è sostituita da una steps of the process and pipelines: “source box” accuratamente scelta dall’analista, mentre la seconda parte viene modellata in CFD. both kinds of components can ope- Ciò consente di ridurre molto l’onere computazionale, pur mantenendo una accuratezza accettabile. rate under pressure that can reach Lo scopo di questo lavoro è fornire una descrizione della source box e una sua caratterizzazione up to 100bar values. The area of attraverso le variabili più importanti nell’evoluzione del fenomeno di rilascio e i relativi range di valori. each deck can be of some hundreds Viene, inoltre, presentato un caso studio per validare la bontà del modello scelto. of square meters, and the height of Parole chiave: CFD, rilasci supersonici, dispersione, source box, piattaforme offshore, analisi di each floor usually ranges between 3 rischio. and 6 meters, which clarifies how congested offshore O&G installa- 1. Introduction construction and management of a tions are. With their complex ge- system and defining the improve- ometry and their customisation to Risk analysis aims at identifying ments and the barriers necessary to specific production objectives and the critical issues of a system, esti- prevent and/or mitigate those con- peculiarities, it is difficult to take mating the damages resulting from sequences. The risk is defined as a advantages from risk and consequen- accidents that may occur during the function of the frequency (evaluated ces analyses performed for other in-

58 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 ambiente stallations. However, in general, the first one is replaced by a “source box” the SST k-ω performs better than possible accidents that can origina- suitably chosen while the second k-ε models in jet impingement site on a platform, and for which a one is CFD modelled in order to re- mulations. Also other authors (Kim consequence analysis is preliminary duce the computational time while et al., 2006) (Chougule et al., 2011) required, are ruptures in any of the maintaining a good accuracy. The supported the use of SST k-ω. pressurised components: these can aim of this work is the description of LES are space averaged NS equa- provoke an immediate formation of the source box characterization. tion with Favre approximation. LES a supersonic under-expanded jet and To fulfil the objectives of the models divide the dominion into the probable jet interaction with work, the release of flammable sub- grid and sub-grid regions with a fil- some of internal platform items. stances (e.g. natural gas) from a hi- ter function that separates flow lar- The main O&G consequences gh-pressure storage has been selected ger eddies (which will be resolved assessment methodologies are based as case study among the reference because anisotropic) and smaller on semi-empirical or CFD models, accidents for an O&G rig. eddies (which will be only model- each one with its advantages and led, because isotropic) of the flow. drawbacks. Nowadays, the empiri- The model is simple but shows some cal models are the most used in the issues in complex turbulent flows si- market (Zio and Pedroni, 2012), 2. Methodology mulation, it is not valid near walls mainly because of their simple and and presents a high computational rapid implementation due to the 2.1. CFD models cost. geometry and physical phenomena DES combines the favourable approximations; unfortunately, it Several CFD models exist and aspects of RANS (efficiency and can result in consequences overe- may be deemed suitable for the simu- accurate calculation at boundary stimation, and therefore in overpro- lations required by the present study. layers) and LES (accuracy in highly tected structures and waste of mate- They are divided into three classes: separated flows) (Spalart and Schur, rials and money. On the other hand, Reynolds Averaged Navier Stokes 1997), thus a temporal and spatial CFD models (Davis et al., 2013) are (RANS), Large Eddy Simulation decomposition. The model is effi- capable to take into account com- (LES) and Detached Eddy Simula- cient and accurate but it needs high plex geometries and phenomena tion (DES). computational resources and it is neglected by the parametric models, Among them, RANS models are still under development. but their computational cost cannot based on the idea that every instan- The peculiarities of these models allow an extensive CFD analysis taneous flow parameter of the Na- and their suitability for the appli- utilization in the platform risk as- vier Stokes (NS) equations can be cation to the offshore context have sessment during the design and decomposed into a time averaged been discussed in a previous work construction phases; therefore, only part and a turbulent fluctuating part, (Impalà, 2016). From the outcomes few scenarios are typically analysed, if the flow is statistically stationary. of the study, for this work, the SST or, anyway, less scenarios than tho- For example, the velocity can be ex- k-ω model was chosen as best fit for se that can be selected using the pressed as in (1): the simulation requirements of the Quantitative Risk Analysis (QRA). u(x, t) = U (x) + u (x, t) (1) phenomenon inside the source box. The CFD simulations may indeed ′ take so long that results become The most common RANS clas- available when the key design choi- ses are the two equation models k-ε 2.2. The source box concept ces are already made. Consequently, and k-ω, which integrate the NS CFD sees its role reduced to a final equation with the kinetic energy The hybrid model (Uggenti et al., verification. Nowadays its impor- transport equation k, the turbulent 2016) considers separately the rele- tance is growing thanks to its major dissipation ε or the specific turbu- ase and the dispersion phase, howe- capability and effectiveness and the lent dissipation ω. The k-ε model ver only the latter is simulated with steady increase of computing power. well represents the round jet and CFD at the time of the consequences This work proposes a deve- the free stream region, as shown in assessment. The first phase, instead, lopment of the hybrid solution pro- Testa et al. (2013), meanwhile the is considered to evolve within the posed at Politecnico di Torino and k-ω well represents the jet impin- source box (Fig. 1) and as such, it is presented by Uggenti et al. (2016) gement. Menter (1993) proposed studied again with CFD: the results targeted to be a compromise betwe- the SST k-ω model which switches in terms of concentrations and velo- en the empirical and the CFD mo- between the k-ε and k-ω according cities are, then, calculated with the dels: this solution splits the accident to free stream or near wall regions. model and defined for the points that evolution in two parts, of which the Yin et al. (2013) demonstrated that lay on the source box surface. The va-

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2.4. Variables and their ranges

In order to describe the phenomenon inside the source box, it is necessary to identify the most influencing variables. The set of source boxes that compose the catalogue is defined according to the values of the most influencing variables. Four variables have been identified to classify the source boxes: release Fig. 1. The source box concept for the simulation of the supersonic release phase. pressure, dimension ratio, rupture Il concetto di source box per la simulazione della fase supersonica di rilascio. diameter and jet direction. The release pressure is probably lues of concentration and velocity of which means that it hosts the space the most important factor due to its the flux on the surface of the source within which the velocity of the jet influence on jet characteristics and box are calculated according to the decreases from the supersonic state domain dimensions. The pressure at input conditions, such as the release to a value that is comparable to the which a flow exits from the rupture pressure and the geometry. Solving wind speed. determines also the fact it is subsonic the whole problem with one single It is possible to define this space or supersonic and the limit is repre- CFD model would pose considerable according to the Stephens hypothe- sented by the critical conditions, as convergence problems as the veloci- sis (Stephens, 2002): the author has defined in (3): ties involved in two main phases (su- shown that after a length equal to 10 personic release and dispersion) have XMach, the expansion phase is closed. 1 p0 C 2 S different orders of magnitude. XMach is the distance between the D T The idea is to create a sort of ca- source and the point where the first pcrit E 1U talogue of source boxes, which the Mach disk appears and it depends analyst can browse to choose the from the storage pressure and from where pcrit is the critical pressure, most suitable one according to the the release diameter: p0 is the ambient pressure and γ is environmental and accidental cha- the specific heat ratio of the relea- racteristics of the case study, without Pstorage sed substance. The release pressure Xd 40 645. (2) the need to re-do the CFD analysis Mach release P influences the release speed in the of the release phase. ambient case of a subsonic jet and it deter- The source box is a ready-for-use mines the critical conditions of a tool of which all the main characteri- The source box dimension cal- supersonic jet; furthermore, when stics are known: the domain, the mo- culated in this way allows to ensure the jet is choked, the release pressu- delling and the mathematics of the that the transition from the super- re determines the substance density phenomenon, the variables which sonic state to the subsonic one of a and, therefore, the mass flow rate. influence the phenomenon within free jet happens within the box: this The source box dimensions are the source box and their ranges. is even more true for the case studies ten times XMach, which is directly Previous studies (Guasco, 2015), that pertain to the O&G rigs, whe- proportional to the square root of (Pederiva, 2015) demonstrated the re jets usually encounter obstacles the release pressure. With this do- possibility to represent the release during their evolution. These real main assumption, when the release phase into a source box and each case jets are slowed down within the pressure increases, the source box author analysed a different jet im- dominion of the source box defined dimensions increase too. An issue pingement against an obstacle. The for the free jet and the transition of related to the release pressure is its present work is specifically dedicated speed is clear. range: on a platform, pressure in to the source box definition and cha- In (Uggenti et al., 2016) this pipes or other containers can be up racterisation. hypothesis has been tested compa- to 100 bar. In this study, a pressure ring calculated results obtained from step of 5 bar is assumed reliable for a CFD simulation in a 10 XMach do- the source box analysis: the pressu- 2.3. The source box model minion with experimental data avai- re values analysed in this work will lable in (Novembre et al., 2006) for be multiple of 5 in the range 5-100 The source box has dimensions a natural gas release. The two data- bar. that allow to host the release phase, sets were in good accordance. There are mainly two geometri-

60 Dicembre 2017 ambiente cal parameters in the source box ratio A between jet and obstacle as: spersion pattern with respect to the setting: the dimension of the obsta- horizontal release. In the source box cle and the distance between obsta- d model presented in this work, the A = jet cle and source. If these parameters cyl d upward, downward and horizontal are taken into account separately, cylinder directions are addressed. the possible combinations are too in the case of the cylinder (4) many and this would not only in- 2.5. Resulting source box crease the difficulty during the djet A = catalogue dimension source boxes description, but, abo- plate L ve all, it would hamper the source plate box choice, which the analyst will in the case of the flat plate. (5) The source box characterisation, do for the case under study. In or- as defined in the previous para- der to ease the proper source box se- The dimensions of the obsta- graphs, leads to an important result lection, it is possible to classify the cle are referred to the face area, that is the evaluation of the catalo- obstacle size and its distance from which, for a plate is its area, but for gue dimension. Having defined the the source with a consideration on a cylinder it is the surface projected range of variability or the type of the impinging jet phenomenon. on the plane normal to the centre- values that each characterising para- It is possible to imagine to have a line. These dimensions represent meter of the source box can assume, jet release with constant characte- the surface that the jet “sees” at the it is possible, in the end, to calculate ristics and its impingement on a impingement. In the case the size of the number of their possible combi- variable size obstacle in front of it. the jet is smaller than the obstacle, nations that is the number of pos- When the jet size, definable with its A tends to zero and the obstacle is sible source boxes the analyst may diameter djet, is bigger than the ob- like an infinite plate on which the choose among when facing a real stacle size, definable as the diameter flow stops. In the case the size of the life offshore platform consequences dcylinder for a cylinder or the width jet is comparable to the obstacle, A analysis. Lplate for a plate, the jet overtakes is equal to 1. In the case the size of In details, Table 1 recaps the ran- the obstacle with only some turbu- the jet is bigger than the obstacle, ges and values of each parameter: lences due to the impingement. In A tends to infinite and the obstacle 20 values are chosen for the release the opposite case, when the jet finds influences the jet like a needle in a pressure, 3 values for the rupture dia- an obstacle with a dimension that is river flow. Classifying the geometry meter, 3 values for jet direction and 3 bigger than djet, the impingement of the source box in this way is an values for dimension ratio. With this blocks the stream which will not approximation as there is a series of categorization, a total of 540 source move anymore along the axis, but infinite possibilities, but this method boxes for each obstacle are identified towards a normal direction. When allows simplifying the approach of and should be analysed. These com- the dimensions are comparable, the the source boxes study in a reliable binations should be foreseen for the impinging jet can have different way as the extreme possibilities are two selected types of obstacle. behaviours, which depend also on considered. The viability of this model has the type of obstacle. In the case of The size of the rupture for risk been tested choosing a set of ten a cylinder, the flow can lose mo- analysis is standardized (OGP, 2010). source boxes for which the dimen- mentum but continues around the For this study, only the smallest va- sional factor A, rupture diameter cylinder body due to the Coanda lues are considered, chosen among and jet direction where defined and a effect for which streamlines of a su- the most probable: 5mm, 30 mm range of ten values of pressure where personic flow move along a curved and 100mm. From its definition, the considered. Besides, the ten source surface without detachment. Shock source box dimensions are directly boxes where analysed for both kinds waves are not observed in this case proportional to the rupture size. of obstacles (leading to a total of 20 because of low Mach numbers (less The jet direction can be upward, source boxes analysed). than 2) reached by the flow. In the downward, horizontal or one of the case of a flat plate, the decrease of infinite diagonal directions betwe- momentum is higher due to a bigger en the horizontal and the vertical opposing face area and flow stream- positions. Even if the horizontal di- 2. Case study lines do not continue on the same rection is the most studied, the ver- direction of the centreline. tical direction should be taken into The case study is based on the In order to move from phenome- account, too: the released substance release of CH4 from a rupture in a nological observations to values, it can move toward the upper or the pressure pipeline or vessel. Figure 2 is possible to define the dimensions lower deck and have a different di- shows the source box for the case of

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Tab. 1. Source box parameters and their ranges of variability. 11n Parametri caratterizzanti della source box e possibili valori che questi possono assumere. O dA B iiA (6) A A i1 Parameter Range or values Pressure 5-100, step 5 bar = 20 values where Φi is the value of the variables on i-cell surface, Ai is the i-cell sur- 0 face and A is the total area of the SB Dimensional factor A 1 surface. Infinite Figures 3 and Figures 4 show an exemplary pattern of CH4 molar con- 5 centration on the planes (horizontal Rupture Diameters (mm) 30 and vertical) passing through the 100 centre of the inlet: it is possible to see how the jet behaves during and after Upward the impingement against the cylin- Jet direction Downward der or the flat plate. In the case of the Horizontal cylinder, the jet overtakes the obstacle and shows the Coanda effect. a cylindrical obstacle. The case study 273mm. The same value is used for In the case of the flat plate, the was performed via a series of simula- the plate width, while its thickness obstacle does not allow the jet to tions with variable release pressures is 100mm. The range of pressure continue in its direction, but it di- and fixed dimension ratio, jet direc- values is 35-80 bar with a step of 5 verts it on the other directions per- tion and rupture diameter. bar, so that 10 values of pressure are pendicularly to the jet axis. The release pressure affects the considered for performing the simu- In Figure 4, the effect of the ob- domain dimensions, therefore at lations. stacle at the impingement zone is every run the source box and the In order to check the accuracy of shown from the point of view of the mesh change. The jet direction is the simulations, the grid indepen- plane normal to that of Figure 3. assumed horizontal, the rupture di- dence analysis was performed. From these figures, it is possible to meter is dexit = 30mm and the di- The number of runs for this series understand that, in the case of the mension ratio is A = 1, meaning the is 10 for each obstacle and the re- cylinder, the source box faces with a obstacle dimension is similar to the sults are obtained as function of the significant concentration are North, jet dimension at the impingement. release pressure. The output value Up and Down, while in the case of In order to characterise the obstacle, of these simulations is the CH4 con- the flat plate these are East, West, a standardized pipe DN250 is consi- centration averaged on the surface Up and Down. dered with an outer diameter dout = according to (6): Table 2 reports the values of CH4

Fig. 2. Source box as domain for CFD simulation of a jet release through an inlet that is represented by a rupture in a pressure pipeline or vessel. a) Half domain with cylinder obstacle and symmetry plane passing through its axis. b) Hexagonal mesh of the source box. c) Nomenclature of the source box faces as reference for the simulation results. Source box come dominio per la simulazione in CFD di un rilascio di un getto attraverso un inlet rappresentato da un foro di rottura in un tubo o un serbatoio in pressione. a) Semidominio con ostacolo cilindrico e piano di simmetria passante per il suo asse. b) Meshatura della source box. c) Nomenclatura delle facce utilizzata per riferire i risultati della simulazione.

62 Dicembre 2017 ambiente concentration on the source box faces, calculated making use of the model chosen according to the considerations reported in the Methodology paragraph. It is possible to notice a decreasing trend in molar fraction in both obstacle shape cases when the pressure release rises. Furthermore, in both cases, Down and Up faces have almost the same CH4 concentration. This is due to the fact these faces are symmetric with respect to the release direction after the impingement, there is no wind interaction that could modify the direction of Fig. 3. Lateral view of a supersonic jet impingement against a) a cylinder and b) a flat the jet after the impingement and plate. the gravity effect in this release pha- Vista laterale dell’impatto supersonico di un getto contro a) un ostacolo cilindrico e b) una se is negligible. piastra. At this point is possible to make some considerations: − the effect of pressure on the domain size is higher than its effect on released gas transportation, in fact: - in case the source box dimensions were the same, the concentration should have incre- Fig. 4. Top view of a jet ased with pressure while, impingement against - if the pressure were constant, a) a cylinder and b) a the concentration should flat plate. have decreased with the Vista dall’alto dell’im- source box dimensions patto di un getto contro - as in this case, when the pres- a) un ostacolo cilindrico sure release increases, the e b) una piastra.

Tab. 2. CH4 molar fraction on the source box faces in case of flat plate or cylindrical obstacle jet impingement. Frazione molare di CH4 sulle facce della source box al variare delle pressioni di rilascio nel caso di ostacolo piastra o ostacolo cilindrico. Faces – Flat plate obstacle Faces – Cylinder obstacle Pressure [bar] Down East Up Down North Up 35 0.00852 0.00978 0.00852 0.00853 0.0156 0.0085 40 0.00803 0.00978 0.00807 0.00802 0.0144 0.00805 45 0.00717 0.00858 0.00714 0.00756 0.0137 0.00758 50 0.00697 0.00864 0.007 0.00725 0.0133 0.00727 55 0.00668 0.00783 0.00668 0.00674 0.0129 0.00674 60 0.00635 0.00783 0.00637 0.00654 0.013 0.00654 65 0.00602 0.00738 0.00607 0.00651 0.0126 0.00652 70 0.00594 0.00722 0.00594 0.00614 0.012 0.00614 75 0.00586 0.00716 0.00587 0.00537 0.0104 0.00538 80 0.00558 0.00681 0.00551 0.00534 0.0102 0.00534

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concentration on the surface References aan Zee, The Netherlands, Sep- decreases, it can be conclu- tember 5-8. ded that the prevailing effect Chougule, N.K., Parishwad, G.V., Pederiva, E., 2015. Towards the CFD is that of the pressure over the Gore, P.R., Pagnis, S., Sapali, S.N., simulation of accidents on off-shore source box dimensions. 2011. CFD analysis of Multi-jet air platforms: dispersion of a turbulent − the model shows the same beha- Impingement on flat plate. Proc. jet hitting a flat plate. MSc Thesis – viour with both kinds of obstacle World Congress on Engineering, Politecnico di Torino. and throughout the range of pres- London, UK, July 6-8. Spalart, P.R., Allmaras, S.R., 1992. A sures. Corti, T., 2016. CFD modelling of ac- one-equation turbulence model for cidental events in Oil&Gas envi- aerodynamic flows. Proc. AIAA 30th ronment: definition of a source box. Aerospace Sciences Meeting and MSc Thesis – Politecnico di Torino. Exhibit, Reno, (NV), 6-9 January. 3. Conclusions Davis, S., Gavelli, F., Hansena, O., Spalart, P.R., Shur M., 1997. On the Middhac, P., 2013. Onshore Explo- Sensitization of Turbulence Models This study allowed to approach sion Studies – Benefits of CFD Mo- to Rotation and Curvature. Aerosp the definition of source boxes with delling. Chemical Engineering Tran- Sci Technol 1, 297-302. the setting of the domain, the CFD sactions, v. 13, pp. 205-273. Stephens, M.J., Leewis, K., Moore, D.K., model, influencing variables and Guasco, S., 2015. Towards the CFD si- 2002. A model for sizing high conse- their ranges. mulation of accidents on off-shore quence areas associated with natu- It can be considered the first step platforms: dispersion of a turbulent ral gas pipelines. Proc. 4th Interna- towards the preparation of a source jet hitting a cylinder. MSc Thesis – tional Pipeline Conference. box catalogue where the most rele- Politecnico di Torino. Testa, E., Giammusso, C., Bruno, M., vant cases are collected. Impalà, M., 2016. Models and Tools for Maggiore, P., 2013. Fluid dynamic The positive aspects of the source the simulation of exhaust dispersion analysis of pollutants’ dispersion box are: in Oil&Gas offshore platforms. MSc behind an aircraft engine during − flexibility, as this approach over- Thesis – Politecnico di Torino. idling. Air Qual Atmos Health 6, takes the problem of case sensiti- International Association of Oil&Gas 367-383. vity Producers, 2010. Risk assessment Uggenti, A.C., Carpignano, A. , Savoldi, − ease of use, as the source box is a Data Directory. Report 434-1 – L., Zanino, R. , Ganci, F., 2016. Per- given black box depending on a Process release frequencies. spective and criticalities of CFD mo- few input conditions Kim, E., Park, S.H., Kwon, J.H., 2004. delling for the analysis of Oil&Gas − expandability, as it is possible to Numerical Study on k – ω Turbulen- offshore accident scenarios, Proc. increase the number of cases ince Models for Supersonic Impinging ESREL 2016, Glasgow, UK, 25-29 creasing the variables or their Jet Flow Field. Computational Fluid September. ranges of values. Dynamics. Springer, 573-578. Yin, J.L., Wang, D.Z., Cheng, H., Gu, A critical aspect of this model is Menter, F.R., 1993,. Zonal two equa- W.G., 2013. Assessment of RANS to represented by the way high pressu- tion k-turbulence models for ae- predict flows with large streamline re releases and large rupture diame- rodynamic flows. NASA Technical curvature. IOP Conference Series: ters are dealt with, as the source box Memorandum 103975. Materials Science and Engineering. domain assumes so large dimensions Novembre, N., Podenzani, F., Co- Vol. 52. No. 2. that they become comparable to the lombo, E., 2006. Numerical study Zio, E., Pedroni, N., 2012. Risk Analysis- entire platform size and the problem for accidental gas releases from Uncertainty characterization in risk description becomes unrealistic. A fi- high pressure pipelines. Proc. Eu- analysis for decision making practi- xed dimension for the source box do- ropean Conference on Compu- ce. Les cahiers de la sécurité indu- main may be necessary in these cases, tational Fluid Dynamics, Egmond strielle. and this is matter for future works. In future works it will also be necessary to look for correlations between the input variables and the flow and concentration parameters Acknowledgment at source box faces in order to produ- This paper would not have been possible without the sponsorship of the Minis- ce the previously discussed catalogue try of Economic Development’s Directorate General for Safety – National Mining without the need to perform all the Office for Hydrocarbons and Georesources. In particular, the authors would like to case by case simulations identified in express their gratitude to the people who have supported this work along all the this work. stages of its realization

64 Dicembre 2017 ambiente

Different types of induced C. Doglioni* * Dipartimento Scienze della Terra, seismicity Università Sapienza di Roma, Istituto Nazionale di Geofisica e Vulcanologia, Roma

Man-made earthquakes should be differentiated as a function of their origin. At least four different types of settings can be recognized in which anthropogenic activities may generate seismicity: 1) fluid removal from a stratigraphic reservoir in the underground can trigger the compaction of excavations (Simpson, 1976; 1986). the voids and the collapse of the overlying volume, e.g., graviquakes; the deeper the reservoir, the It was pointed out that industrial ac- bigger the volume and the earthquake magnitude; 2) wastewater or gas reinjection provides the tivities do not supply energy to the reduction of friction in volumes and along fault planes, allowing creep or sudden activation of tec- geological phenomena, but they only tonic discontinuities; 3) fluid injection at supra-lithostatic pressure determines hydro-fracturing and micro-seismicity; 4) fluid extraction or fluid injection, filling or unfilling artificial lakes modifies the accelerate them in lowering the fric- lithostatic load, which is the maximum principal stress in extensional tectonic settings, the minimum tion on tectonic structures already at principal stress in contractional tectonic settings, and the intermediate principal stress in strike-slip a critical state of stress failure when settings; over given pressure values, the increase of the lithostatic load may favour the activation of fluids increase the pore pressure normal faults, whereas its decrease may favour thrust faults. For example, the filling of an artificial (Walsh and Zoback, 2015). Eviden- lake may generate normal fault-related seismicity. Therefore, each setting has its peculiarities and ces of seismicity induced by injecting the knowledge of the different mechanisms may contribute to adopt the correct precautions in the wastewater fluids in depleted oil re- various industrial activities. servoirs are well established (Valo- Keywords: anthropogenic seismicity, graviquakes, pore pressure increase, hydro-fracturing, varia- roso et al., 2009; Stabile et al., 2014; tions of the lithostatic load. Improta et al., 2015; Buttinelli et al., 2016), but also for gas storage (Ruiz- Diverse tipologie di sismicità indotta. I terremoti correlati ad attività industriali devono essere differenziati in funzione della loro origine. Vi sono almeno quattro diversi tipi di sismicità correla- Barajas et al., 2017 and references bile a tali attività: 1) la rimozione di idrocarburi da un livello stratigrafico a porosità primaria può therein). Therefore, a scientifically determinare il collasso del volume sovrastante, cioè la generazione di gravimoti, la cui magnitudo grounded policy on induced sei- dipende dal volume che è tanto più grande quanto più è profondo il giacimento (ad esempio la smicity is required (Giardini, 2009; sismicità di bassa magnitudo di Groningen); 2) la reinieizione di acque reflue o fluidi in generale, McGarr et al., 2015; Langenbruch oltre determinate soglie di quantità e di pressione, può diminuire l’attrito nei volumi e sui piani di and Zoback, 2016; Braun et al., 2016; faglia, abbassando la pressione efficace e arrivare a provocare sismicità indotta o anche innescata; Grigoli et al., 2017). In this paper, a 3) l’immissione di fluidi non comprimibili a pressione sovralitostatica genera idrofratturazione e classification of different types of in- correlata microsismicità; 4) l’estrazione o l’immissione di fluidi nel sottosuolo, come anche il riempi- duced seismicity is proposed in order mento o lo svuotamento di invasi artificiali, determina una variazione del carico litostatico che può to provide a clue for discriminating generare sismicità se i volumi superano determinate soglie. Il carico litostatico è lo stress massimo among the several tectonic settings per gli ambienti estensionali, minimo per quelli compressivi e intermedio per quelli trascorrenti. Di and the effects of the anthropogenic conseguenza, il riempimento di invasi lacustri può per esempio determinare l’attivazione di faglie normali, lo svuotamento viceversa attivare faglie inverse. La conoscenza delle diverse tipologie di perturbations. A number of useful sismicità indotta o innescata è un pre-requisito per adottare le giuste misure precauzionali nelle classifications have already been pro- varie attività industriali. posed. Here it is discussed the rela- Parole chiave: sismicità antropogenica, gravimoti, aumento pressione di poro, idrofratturazione, tionship of induced seismicity with modificazioni del carico litostatico. respect to the hydrostatic and lithostatic pressures, respectively.

1. Introduction othermal exploitation. It was shown how human activities can determine Even if the discrimination for na- the magnitude of the events as a fun- 2. Types of seismicity tural versus anthropogenic seismicity ction of the volume and rate of fluid associated to human is not always straightforward (Dahm injected (McGarr, 2014; Weingarten activities et al., 2015), seismicity induced by et al., 2015). Particularly in Oklaho- fluid injection was proven by Ralei- ma the rate of seismicity had a drastic gh et al. (1976). Fluid removal from increase due to wastewater injection The terms induced and triggered the subsurface or fluid injection in at depth (Ellsworth, 2013; Keranen seismicity are used to differentiate the subsurface are associated to in- et al., 2014). Earthquakes were disco- seismicity generated by industrial dustrial operations, particularly wa- vered as also controlled by loading operations and natural seismicity stewater disposal, gas storage or ge- effects on artificial lakes and quarry catalyzed and anticipated by human

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 65-68 65 environment activities. The transition among the km3, which would correspond to an of operational techniques are more two types of seismicity is subtle be- energy dissipation of an earthquake frequently used at shallow depth and cause the crust is widely at a critical of about M 3.5-4, being M 3.6 the therefore are usually associated only state of stress and very often the in- largest magnitude recorded in the to superficial microseismicity, which duced seismicity can be considered gas field (Van Weeset al., 2014). To may be felt particularly for its low as triggered, regardless the lithology support the simple interpretation of depth. Fracking has been shown able and the tectonic setting. Here, for compaction and creeping and the to generate earthquakes at least up to sake of simplicity, we consider all coseismic collapse, the gas field ex- M 3.9. Hydro-fracturing is also a well anthropogenic seismicity as indu- ploitation has generated a subsiden- known natural phenomenon, since ced, implying a potential activation ce of about 20-30 cm (van Thienen- the rock record shows the effects of of faults ready to move, disregarding Visser and Breunese, 2015). The deformation by overpressured fluids their regional tectonic significance. larger the fluid removal, the bigger possibly associated to coseismic phe- The basic rationale is to analyse the will be the potentially collapsing nomena (Doglioni et al., 2014). This different human activities with re- volume and the induced seismicity. is type 3 induced seismicity in Fig. 1. spect to deviations from the hydro- This is type 1 induced seismicity in static and lithostatic natural pressu- Fig. 1. 2.4. The fluid extraction or fluid res (Fig. 1). The hydrostatic pressure injection in the underground, or is assumed to increase 10 MPa/km, 2.2. Saltwater or gas reinjection the filling or unfilling of artificial whereas the lithostatic load in the in the subsurface provides the re- lakes modifies the lithostatic load, upper crust may increase in the ran- duction of friction in volumes and which is the maximum principal ge of 23-27 MPa/km, as a function of along fault planes, allowing creep stress in extensional tectonic set- the rock density (2.3-2.7 g/cm3). or sudden activation of tectonic tings, the minimum principal stress discontinuities. The increase of in contractional tectonic settings, 2.1. The removal of gas or oil from the pore pressure to values larger and the intermediate principal stress a stratigraphic play with primary than those naturally occurring in a in strike-slip settings. Over given porosity can trigger the compaction crustal volume may determine the pressure values, the increase of the of the voids and the collapse of the activation of faults, regardless the lithostatic load may favour the acti- overlying volume, provoking seismi- tectonic setting. The crust has been vation of normal faults, whereas its city and subsidence. An example demonstrated to be at a critical state decrease may favour thrust faults. is the Groningen field in Holland of stress, close to failure, and small For example, the filling of an artifi- (van Thienen-Visser and Breunese, perturbations of the pore pressure cial lake may generate normal fault- 2015), in which the gas reservoir is may determine the activation of related seismicity. The maximum located at about 3 km depth in the rock rupture of sliding along well- magnitude inferred for this type of porous eolian-fluvial sandstones Per- oriented fault planes with respect induced/triggered seismicity is M 6.5 mian Rotliegend Formation. Focal to the regional stress field (e.g., Alt at Koyna Reservoir in India in 1967 mechanisms of the induced seismici- and Zoback, 2017). The maximum (Gupta and Rastogi, 1976; Gupta, ty generated by the gas field are in- magnitude reported for this type of 2002). Fluids may also penetrate in dicating normal faulting. It has been induced/triggered seismicity in Ok- the underground contributing to de- shown that normal faults-related lahoma is the Pawnee M 5.8 2016 crease friction. This is type 4 indu- earthquakes are the dissipation of event (Langenbruch and Zoback, ced seismicity in Fig. 1. This induced stored gravitational energy and the 2016). Far field pressurization may seismicity may occur regardless rocks depth of the activated seismic volu- concur to generate seismicity even are pre-fractured or not, but it is cle- me is about one third of the length at several km distance with respect arly more feasible in case of pre-exi- of the collapsing hangingwall (i.e., to the injection wells (Yeck et al., sting weaker naturally pre-fractured the graviquakes, Doglioni et al., 2016). There is not a general th- bands, or faults at a critical state of 2015). It implies that the deeper reshold, but the deeper the reservoir failure. the reservoir, the bigger the volume of fluid injection, the larger must be and the earthquake magnitude. In the over pressure in order to activate the Groningen example, the fluid induced seismicity. This is type 2 in- removal from the voids of the san- duced seismicity in Fig. 1. 3. Concluding remarks dstone could allow the collapse of the overlying thickness of the strati- 2.3. The fluid injection at supra-li- The are different types of indu- graphic sequence. Being 3 km the re- thostatic pressure determines hydro- ced or triggered seismicity that can servoir depth, the maximum volume fracturing and micro-seismicity; this be classified as a function of the that could be mobilized is around 40 is known as fracking, but this type tectonic setting, the fluids volu-

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of inherited thrusts by wastewater injection induced seismicity at the Val d’Agri oilfield (Italy). Scientific Fig. 1. Illustration of reports, 6. the four main types of Dahm, T., Cesca, S., Hainzl, S., Braun, anthropogenic seismici- T. and Krüger, F., 2015. Discrimi- ty described in the text. MPa, Mega Pascal. The nation between induced, triggered, lithostatic load is compu- and natural earthquakes close to ted assuming a mean up- hydrocarbon reservoirs: A probabi- per crust density of 2.7 g/ listic approach based on the mo- cm3, implying a growth of deling of depletion-induced stress the load of 27 MPa/km. changes and seismological source Illustrazione dei quattro parameters. Journal of Geophysi- principali tipi di sismicità cal Research Solid Earth, v. 120, antropogenica descritti nel doi:10.1002/2014JB011778. testo. MPa, Mega Pascal. Il Doglioni C., Barba S., Carminati E., carico litostatico è assun- and Riguzzi F., 2014. Fault on- to ipotizando una densità off versus coseismic fluids reac- media della crosta supe- tion. Geoscience Frontiers, v. 5, 6, riore di 2.7 g/cm3, che im- pp. 767-780, doi.org/10.1016/j. plica una aumento di 27 gsf.2013.08.004 MPa/km. Doglioni, C., Carminati, E., Petricca, P., Riguzzi, F., 2015. Normal fault me and pressure variations relative seismicity, whereas the unloading earthquakes or graviquakes. Scienti- to the hydrostatic and lithostatic may induce thrust fault activity. fic Reports, 5, 12110 doi:10.1038/ trends. At least four different types Furthermore, all these types of in- srep12110. of anthropogenic seismicity can be duced seismicity are controlled by Ellsworth, W.L., 2013. Injection-in- classified, each one characterized a wide number of local variable duced earthquakes. Science. 341 by its values of maximum magnitu- parameters, such as depth of fluid (6142), 7. doi: 10.1126/scien- de. The fluid removal from a strati- injection/removal, fluid volume ce.1225942. graphic reservoir can generate the injected/removed, rate and pressu- Giardini, D., 2009. Geothermal quake collapse of the overlying volume re of fluid injection/removal; litho- risk must be faced. Nature 462, due to the voids closure and com- logy, primary or secondary porosity, 848-849. paction (type 1). This mechanism heat flow, tectonic environment, Grigoli, F., Cesca, S., Priolo, E., Rinaldi, may provide a sub-hydrostatic con- regional strain rate, rock rigidity, A.P., Clinton, J.F., Stabile, T.A., Dost, dition. The magnitude increases fault friction, type and viscosity of B., Fernandez, M.G., Wiemer, S., with the depth of the reservoir and fluids, etc. Dahm, T., 2017. Current challenges the amount of collapsing volume. in monitoring, discrimination, and Conversely, the increase of the fluid management of induced seismicity pressure due to fluid injection may related to underground industrial generate a fluid overpressure and a References activities: a European perspecti- supra-hydrostatic condition; this ve. Reviews of Geophysics 55 (2), can generate induced seismicity Alt, R.C., and Zoback, M.D., 2017. In 310 e 340. (type 2). Fluid injection at pressu- Situ Stress and Active Faulting in Ok- Gupta, H.K., 2002. A review of recent re higher than the lithostatic load lahoma. Bulletin of the Seismolo- studies of triggered earthquakes may determine fracturing of rocks, gical Society of America, v. 107, 1, by artificial water reservoirs with i.e., the so-called fracking (type 3). doi: 10.1785/0120160156 special emphasis on earthquakes The loading and unloading of rocks Braun, T., Dahm, T., Krüger, F., and in Koyna, India. Earth Science Re- and fluids on the crust generate an Ohrnberger, M., 2016. Does views, v. 58, pp. 279-310. increase or decrease of the lithosta- Geothermal Exploitation Trig- Gupta, H.K., and Rastogi, B.K., 1976. tic load, which is σ1 in extensional ger Earthquakes in Tuscany? Eos, Dams and Earthquakes. Elsevier, settings or σ3 in contractional tec- Eos, 97, https://doi.org/10.1029/ Amsterdam, pp. 229. tonic settings (type 4). Therefore, 2016EO053197. Improta, L., Valoroso, L., Piccinini, D. an increase of the lithostatic load Buttinelli, M., Improta, L., Bagh, S., & Chiarabba, C., 2015. A detailed may induce normal faulting-related and Chiarabba, C., 2016. Inversion analysis of wastewater-induced sei-

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smicity in the Val d’Agri oil field, Italy. Earth and Planetary Sciences, v. induced seismicity during gas field Geophysical Research Letters, 42, 14, pp. 21-42. depletion in the Netherlands. Geo- 2682-2690. Stabile, T.A., Giocoli, A., Perrone, A., thermics, v. 52, pp. 206-219. Keranen, K.M., Weingarten, M., Abers, Piscitelli, S. & Lapenna, V., 2014. Yeck, W.L., Weingarten, M., Benz, G.A., Bekins, B.A., Ge, S., 2014. Fluid injection induced seismicity H.M., McNamara, D.E., Bergman, Sharp increase in central Oklahoma reveals a NE dipping fault in the E.A., Herrmann, R.B., Rubinstein, seismicity since 2008 induced by southeastern sector of the High J.L., and Earle, P.S., 2016. Far-field massive wastewater injection. Scien- Agri Valley, southern Italy. Geo- pressurization likely caused one ce. v. 345 (6195), pp. 448-451. physical Research Letters, v. 41, of the largest injection induced PMID 24993347. doi: 10.1126/ pp. 5847-5854. earthquakes by reactivating a lar- science.1255802. Valoroso, L., Improta, L., Chiaraluce, L., ge preexisting basement fault Langenbruch C., Zoback, M.D., 2016. Di Stefano, R., Ferranti, L., Govoni, structure. Geophysical Research How will induced seismicity in Okla- A., & Chiarabba, C., 2009. Active Letters, v. 43, pp. 10,198-10,207, homa respond to decreased saltwa- faults and induced seismicity in the doi:10.1002/2016GL070861. ter injection rates? Science Advan- Val d’Agri area (Southern Apennines, Walsh, F.R.I., and Zoback, M.D., 2015. ces. v. 2, no. 11, e1601542, DOI: Italy). Geophysical Journal Interna- Oklahoma’s recent earthquakes 10.1126/sciadv.1601542 tional, v. 178(1), pp. 488-502. and saltwater disposal. Science McGarr, A., 2014. Maximum ma- van Thienen-Visser, K., and Breune- Advances, v. 1, no. 5, e1500195, gnitude earthquakes induced by se, J.N., 2015. Induced seismicity of DOI: 10.1126/sciadv.1500195 fluid injection. Journal of Geo- the Groningen gas field: History and Weingarten, M., Ge, S., Godt, J.W., Be- physical Research Solid Earth, v. recent developments. The Leading kins, B.A., Rubinstein, J.L., 2015. Hi- 119, pp. 1008-1019, doi:10.1002/ Edge, v. 34(6), pp. 664-671. gh-rate injection is associated with 2013JB010597. Van Wees, J.D., Buijze, L., Van Thienen- the increase in U.S. mid-continent McGarr, A., Bekins, B., Burkardt, N., Visser, K., Nepveu, M., Wassing, seismicity. Science, v. 348 (6241): Dewey, J., Earle, P., Ellsworth, W., B.B.T., Orlic, B., and Fokker, P.A., pp. 1336-1340, doi: 10.1126/scien- Ge, S., Hickman, S., Holland, A., Ma- 2014. Geomechanics response and ce.aab1345. jer, E., Rubinstein, J., and Sheehan, A., 2015. Coping with earthquakes induced by fluid injection. Science, v. 347, no. 6224, pp. 830-831, doi: 10.1126/science.aaa0494. Raleigh, C.B., Healy, J.H. Bredeho- eft, J.D., 1976. An Experiment in Earthquake Control at Rangely, Co- lorado. Science, v. 191, Issue 4233, pp. 1230-1237. Ruiz-Barajas, S., Sharma, N., Conver- tito, V., Zollo, A., Benito, B., 2017. Temporal evolution of a seismic sequence induced by a gas injection in the Eastern coast of Spain. Scientific Reports, v. 7, 2901 DOI:10.1038/ s41598-017-02773-2. Schultz, C., 2013. Marcellus Shale fracking waste caused earthquakes in Ohio. Eos, Transactions American Geophysical Union, v. 94(33), pp. 296-296. Simpson, D.W., 1976. Seismicity changes associated with reservoir loading. In: W.G. Milne (Editor), In- duced Seismicity. Engineering Ge- Acknowledgement ology, v. 10(2-4), pp. 123-150. Discussions with Franco Terlizzese, Thomas Braun, Claudio Chiarabba, Daniela Simpson, D.W., 1986. Triggered Di Bucci, Riccardo Lanari, Liliana Panei, Enrico Priolo and Aldo Zollo were very earthquakes. Annual Reviews of fruitful.

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F. Ciccone* Seismic monitoring of E. Priolo** G. Teofilo* underground activities for I. Antoncecchi* energy production: survey R. Lanari*** * Ministry of Economic Development – of the existing facilities with DGS UNMIG, Rome Italy ** Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, reference to the Italian Sezione Scientifica Centro di Ricerche Sismologiche – CRS, Sgonico (TS) – Italy monitoring guidelines *** CNR-IREA – Consiglio Nazionale delle Ricerche, Istituto per il Rilevamento Elettromagnetico dell’Ambiente, Napoli, Italy This paper reports the results of a study aimed at analyzing the existing seismic monitoring infrastructures of underground activities for energy production. The study was carried out by the Italian National Institute of Oceanography and Applied Geophysics (OGS), in collaboration with the Italian National Research Council – Institute for Electromagnetic Detection of the Environment (CNR- IREA), in the framework of the partnership established by the Ministry of Economic Development, 1. Introduction Directorate General for Safety of Mining and Energy Activities – National Mining Office for Hydro- carbons and Georesources (MiSE DGS-UNMIG), with Italian Universities and Research Institutions Following the Emilia seismic se- within the so-called “Network for Offshore Safety”. Firstly, a survey was carried out by sending a quence of 2012 (Pizzi & Scisciani, questionnaire to companies to gather information about the infrastructures and procedures for 2012; Scognamiglio et al., 2012; monitoring seismicity, ground deformation and pore pressure, respectively, implemented within the Emergeo Working Group, 2013) hydrocarbon exploitation fields for either production or re-injection or gas-storage currently present an international commission, the in Italy. Then, the data obtained by the survey were analyzed with reference to the requirements of “International Commission on the “Italian Guidelines for monitoring the seismicity, underground deformation and pore pressure” Hydrocarbon Exploration and Sei- (ILG) (Dialuce et al., 2014), in order to establish the possible needs for upgrading and, subsequently, smicity in the Emilia Region” (he- assessing the relative costs. This paper reports the evaluation of the technical part, i.e. that concer- reinafter called ICHESE) was ap- ning the upgrade of the monitoring systems. pointed by the “Commissioner for Keywords: seismic monitoring, monitoring guidelines, ground deformation, pore pressure monito- the Earthquake of the Italian Go- ring, underground activities. vernment” to evaluate the possibili- Monitoraggio sismico delle attività svolte nel sottosuolo per la produzione di ener- ty that the earthquake sequence had gia: indagine delle infrastrutture esistenti in relazione alle linee guida italiane per been caused by some of the activities i monitoraggi. Questo articolo descrive i risultati di uno studio finalizzato all’analisi delle in- carried out in the subsurface of the frastrutture di monitoraggio sismico esistenti sul territorio italiano nell’ambito delle attività svolte area. At the end, the ICHESE Com- nel sottosuolo per la produzione dell’energia. Lo studio è stato condotto dall’Istituto Nazionale di mission emphasized the need that all Oceanografia e di Geofisica Sperimentale (OGS), in collaborazione con il Consiglio Nazionale delle the existing and future activities of Ricerche-Istituto per il Rilevamento Elettromagnetico dell’Ambiente (CNR-IREA), nell’ambito della hydrocarbon exploitation (i.e. pro- collaborazione stabilita dal Ministero dello Sviluppo Economico Direzione Generale per la Sicurez- duction, re-injection and gas-stora- za anche ambientale delle attività minerarie ed energetiche-Ufficio Nazionale Minerario per gli ge) and geothermal energy produc- Idrocarburi e le Georisorse (MiSE DGS-UNMIG) con Università ed Enti di Ricerca italiani nell’am- tion carried out underground were bito del c.d. “Network della sicurezza offshore”. Nella prima parte dell’indagine è stato inviato to be constantly monitored through un questionario alle compagnie per raccogliere informazioni sulle infrastrutture e le procedure high-quality networks (ICHESE, di monitoraggio della sismicità, della deformazione del suolo e della pressione di poro realizzate 2014), in order to have a clear and all’interno campi di sfruttamento idrocarburi, per la produzione, la re-iniezione, o lo stoccaggio del detailed account of the evolution of gas, attualmente presenti in Italia. Successivamente, i dati ottenuti dall’indagine sono stati ana- the seismicity, including the micro- lizzati con riferimento a quanto prescritto dalle “Linee Guida per il monitoraggio della sismicità, delle deformazioni del suono e della pressione di poro” (ILG) (Dialuce et al., 2014), con lo scopo seismicity, the ground deformation, di individuare le eventuali necessità di upgrade e, in conseguenza, stimare i relativi costi. Questo as well as the pore pressure, respecti- articolo descrive la valutazione della parte tecnica, cioè quel che concerne l’upgrade dei sistemi di vely. Integrated monitoring is indeed monitoraggio. considered as one of the fundamen- Parole chiave: monitoraggio sismico, Linee Guida per il monitoraggio, deformazione del suolo, mo- tal tasks to ensure the highest level nitoraggio delle pressioni di poro, attività svolte nel sottosuolo. of safety standard.

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 69-72 69 environment

On the basis of the ICHESE rently implemented to monitor sei- 1) General information: informa- Commission recommendations, the smicity, soil deformation and pore tion about the operator, a descrip- Ministry of Economic Development, pressure, respectively. Then, the tion of the activity and the licen- Directorate General for Safety of existing systems were analyzed and se area was required. Mining and Energy Activities – Na- evaluated against the Guidelines’ 2) Reservoir data: area extension, tional Mining Office for Hydrocar- criteria, in order to understand the depth, thickness and type of rock bons and Georesources (hereinafter possible need for upgrading to Gui- of the reservoir. MiSE DGS-UNMIG) set up a spe- delines’ standard. Finally, a prelimi- 3) Existing wells: this part summari- cific Work Group to define techni- nary estimation of the costs needed zes well data, i.e. provide coordi- cal guidelines for such monitoring for the upgrade was performed for nates, depth, and type of measure- systems. The resulting document, each license. However, this paper ments carried out. Well position entitled “Guidelines for monitoring reports only the results of the tech- compared to reservoir (in/out), in seismicity, ground deformation and nical analysis, and the latter analyses case of water reinjection. pore pressure in subsurface indu- about the costs is not described. 4) Geological setting: information strial activities” (hereinafter called (with maps and sections if avai- “Guidelines” or ILG) was published lable) about the geological, tec- in December 2014 (Dialuce et al., tonic and structural setting of the 2014). The Guidelines address in 2. The survey site, the seismicity, and an estima- detail both how monitoring should tion of the variation of the litho- be carried out and performed, and At present, 15 licenses for either static load due to the activity was the procedures that should be imple- hydrocarbon exploitation or gas- required. mented in order to pursue an effec- storage are equipped with seismic Each operator was asked to indi- tive control. It is also recommended monitoring systems in Italy. For the cate which and how much data was to test and verify the first implemen- survey, a questionnaire was drawn up available for each license. tations of the Guidelines on some to gather all the pieces of informa- pilot sites; this should be done not tion useful to evaluate the existing only for the technical part (i.e. re- systems with reference to the Gui- 2.2. Seismic monitoring alization, management, and control delines. This questionnaire was then network of the monitoring), but especially for sent out to each of the 15 license the procedures to be adopted in the holders. Regarding seismic monitoring, case of variation of the monitored The questionnaire was drawn up the ILG requires the following for parameters (Macini et al., 2015). In following the technical specifica- the monitoring network: the case of existing monitoring in- tions indicated by the Guidelines in 1. to detect events with local Ma- frastructures, Guidelines suggests to order to obtain a sufficiently detai- gnitude in a range of 0

70 Dicembre 2017 ambiente transmission mode. real-time data processing (if per- and connectivity test between wells Then, information about the formed) that off-line and correla- were carried out was required. existing procedures was asked, i.e. tion analysis with the activity. 2.5 Use of monitoring in connection details about “quasi-real-time” and – InSAR Monitoring. This section with activities “off-line” data analysis procedures, collects data about the subject re- The last section of the question- detection and localization methods, sponsible for the monitoring data naire dealt with monitoring mana- monitoring performance evaluation, management, as well as the main ging structure, the criteria adopted including the way in which they are features of the InSAR data used to evaluate the monitoring results carried out respectively, picking qua- for monitoring (such as the sensor in connection to the activity car- lity control, location error estima- type, the mode and the acquisi- ried out, and the intervention pro- tion and completeness magnitude tion orbit, ascending/descending, cedures set up in case of variation estimate. Details about the current angle of view, spatial extension, of the monitored parameters. Spe- data analysis procedures were also and acquisition time period). cifications on whether the operator required. Furthermore, it is also necessary had adopted a traffic-light system Two pieces of information are also to describe the techniques used were sought. In that case, the levels important to evaluate the effective- for InSAR data processing and of activation should be specified, as ness of the monitoring service. The their possible integration with well as the possible involvement of first is to know whether a seismic- information provided by the GPS government, public administration, alarm service exists, including on- network, if available, in order to civil protection, or security authori- call duty. The second is which kind achieve ILG requirements. ties in the decision-making system. of analyses is carried out to establish – Precision Geodetic Leveling. A possible correlations between sei- description of the characteri- smicity and activity. stics of geodetic leveling, such as the classification of leveling, the 3. Results and Concluding level of leveling, the signaling remarks 2.3. Soil deformation monitoring of the strongholds, instrument network used (mechanical or digital op- The elaborated survey is bound tical levels, material of the sta- to be confidential, as it contains The questionnaire on Interfero- diums), and any other auxiliary sensitive industrial data. This is the metric Synthetic Aperture Radar equipment was required. Finally, reason for not providing details of (hereinafter InSAR) monitoring was an indication on how technical which licenses were examined, and carried out in collaboration with the reporting is performed. which companies were involved; ne- Italian National Research Council vertheless, some fundamental infor- – Institute for Electromagnetic De- mation is summarized below. tection of the Environment (CNR- 2.4. Pore pressure monitoring The survey on the systems imple- IREA). This part is divided into th- network mented for monitoring seismicity, ree sections, i.e. Global Navigation soil deformations, and pore pressures, Satellite System geodetic monito- The last section of the question- respectively, was carried out for 15 ring (hereinafter GNSS), InSAR naire was about the characteristics of licenses of underground activity of monitoring, and precision geodetic pore pressure monitoring addressed hydrocarbon exploitation (i.e. pro- leveling, respectively: in the ILG. The section was designed duction, reinjection and gas-storage) – GNSS Geodetic Monitoring. In to obtain information about the mo- for energy production. All the con- this section, a general description nitoring plan, in particular number tacted companies replied positively of the monitoring plan is asked, of wells, monitored parameters, an to the survey request. The question- with details about the subject re- indication of pressures of extracted naires sent out to the operators were sponsible for the monitoring data or injected fluids was required as well filled out for all 15 licenses. Almost management. Similarly to sei- as specifications of where the mea- all concessions perform some kind smic monitoring, it is also asked surements were made, well head or of integrated monitoring as shown to indicate the number of CGPS bottom, also if they were dynamic from the survey analysis. However, stations and the distance betwe- (wells in operation) or static (wells it is still necessary to determine how en them, instrument technical not in operation) pressures. A de- much of the characteristics of the features such as the acquisition scription of formation permeability monitoring performed meet the re- frequency, the patterns used, the characteristics in which the fluids quirements of the ILG. Seismic mo- ellipsoidal volume, and the data were extracted/injected or measure- nitoring is carried out in all conces- transmission mode. In addition, ments were made and if permeability sions, except for 3 licenses, although

Dicembre 2017 71 environment with very different quality levels. del suolo e delle pressioni di poro appendices: http://geo.regione. Soil deformation monitoring is carri- nell’ambito delle attività antropiche. emilia-romagna.it/gstatico/docu- ed out at all concessions. Most con- 38 pp. Published on line on 24th menti/ICHESE/Appendices.pdf, cessions are equipped with InSAR november 2014. http://unmig.svi- last access: April 2015. and GNSS monitoring, sometimes luppoeconomico.gov.it/unmig/. Macini, P., Mesini, E., Panei, L., Terlizze- combined with precision geodetic agenda/upload/85_238.pdf. se, F., 2015. Land subsidence, seismi- leveling. InSAR monitoring is not Emergeo Working Group, 2013. Li- city and pore pressure monitoring: carried out at 2 licenses; however, in quefaction phenomena associated the new requirements for the future those cases soil deformation is moni- with the Emilia earthquake sequen- development of oil and gas fields in tored by precision geodetic leveling. ce of May-June 2012 (Northern Italy. Proceedings of the Interna- The porous pressure monitoring is Italy). Nat. Hazards Earth Syst. tional Association of Hydrological carried out at all concessions in some Sci. 13, 935-947. http://dx.doi. Sciences; Gottingen 372: 533-538. ways, although great attention must org/10.5194/nhess-13-935-2013. Gottingen: Copernicus GmbH. be paid to the measurements actual- Grigoli, F., Cesca, S., Priolo, E., Rinaldi, Pizzi, A., Scisciani, V., 2012. The May ly implemented. Finally, it should be A.P., Clinton, J.F., Stabile, T.A., Dost, 2012 Emilia (Italy) earthqua- noted that for many sites the level of B., Garcia Fernandez, M., Wiemer, kes: preliminary interpretations knowledge about the geology, struc- S. and Dahm, T., 2017. Current chal- on the seismogenic source and tural geology, and seismotectonics, lenges in monitoring, discrimina- the origin of the coseismic ground respectively, is poor. The results of tion, and management of induced effects. Ann. Geophys., 55, 751- the survey indicate that the existing seismicity related to underground 757, http://www.ann-geophys. monitoring plans of the 15 Italian industrial activities: A European net/55/751/2012/. licenses considered in this study perspective. Rev. Geophys., 55, Scognamiglio, L., Margheriti, L., Mele, comply only in part with the ILG doi:10.1002/2016RG000542 F.M., Tinti, E., Bono, A., De Gori, P., suggestions. In particular, monitored ICHESE, 2014. International Commis- Lauciani, V., Lucente, F.P., Mandiello, data are only available internally to sion on Hydrocarbon Exploration A.G., Marcocci, C., Mazza, S., Pin- the companies and the knowledge and Seismicity in the Emilia Region: tore, S., Quintiliani, M., 2012. The about the geology, geodynamics and Report on the Hydrocarbon Ex- 2012 Pianura Padana Emiliana seismotectonics is often restricted to ploration and Seismicity in Emilia seimic sequence: locations, moment a smaller scale than that suggested Region. http://geo.regione.emilia- tensors and magnitudes. Annals of by the ILG and useful to establish or romagna.it/gstatico/documenti/ Geophysics, 55, 4; doi:10.4401/ag- rule out possible correlations betwe- ICHESE/ICHESE_Report.pdf, with 6159. en the activities and seismicity, especially for the case of events triggered on existing faults. We eventually emphasize that this study, and in general the overall action of upgrading the existing monitoring systems, is compliant with the most advanced scientific suggestions provided at international level (Grigoli et al., 2017) with the aim of improving the management of the induced seismicity problem in a perspective of increased safety and risk reduction.

References

Dialuce, G., Chiarabba, C., Di Bucci, Acknowledgement D., Doglioni, C., Gasparini, P., Lanari, This study has been funded by the Italian Ministry of Economic Development, R., Priolo, E., Zollo, A. 2014. Indiriz- DGS-UNMIG, within the Program Agreement with the National Institute of Oce- zi e linee guida per il monitoraggio anography and Applied Geophysics in the framework of the “Network for Offshore della sismicità, delle deformazioni Safety”.

72 Dicembre 2017 ambiente

G. Solaro* Ground deformation M. Manzo* M. Bonano*,** analysis through spaceborne R. Castaldo* F. Casu* SAR interferometry and C. De Luca* geophysical modelling V. De Novellis* M. Manunta* S. Pepe* We present the main activities and the most significant results that the Institute for Electromagnetic P. Tizzani* Sensing of the Environment (IREA) of the National Research Council (CNR) has retrieved within I. Zinno* the framework of its collaboration with the Ministry of Economic Development (MiSE) – Director- R. Lanari* ate-General for Safety of Mining and Energy Activities National Mining Office for Hydrocarbons and Georesources (DGS-UNMIG). In particular, this agreement aims at detecting and monitoring surface * Istituto per il Rilevamento deformation affecting the areas of particular interest for the DGS-UNMIG through space-borne Elettromagnetico dell’Ambiente (IREA), Differential SAR (Synthetic Aperture Radar) Interferometry (DInSAR) analysis and multi-parameters Consiglio Nazionale delle Ricerche and multi-physics modelling. The first ones provide information on the spatial distribution of the (CNR), Napoli (Italy) retrieved ground displacements and their temporal evolution, the second on the geological/geo- ** Istituto di Metodologie per l’Analisi physical processes that characterize the investigated areas. In this work, we present the preliminary Ambientale (IMAA), Consiglio results retrieved via interferometric analysis performed by exploiting SAR data acquired from the Nazionale delle Ricerche (CNR), first (ERS-ENVISAT) and second (Sentinel-1) generation sensors over the Emilia-Romagna Region Potenza (Italy) (North Italy) and the entire Italian Peninsula, respectively. Moreover, we performed a 3D geological-structural model of the Cavone site (Emilia-Romagna) and a 3D FEM (Finite Element Method) model for simulating the co-seismic dislocation of the M6.0 and M5.8 seismic events, which occurred on 20/05/2012 and 29/05/2012 over Emilia-Romagna region, respectively. Keywords: surface deformation, differential SAR interferometry, small baseline subset, geophysical levant to temporally separated radar modelling, 2012 Emilia Romagna’s earthquake. observations of the analyzed area and acquired from sufficiently close Analisi delle deformazioni del suolo mediante interferometria satellitare SAR e mo- orbits (baseline). In particular, this dellazione geofisica. In questo lavoro presentiamo le principali attività ed i risultati più significativi technique allows detecting defor- che l’Istituto per il Rilevamento Elettromagnetico dell’Ambiente (IREA) del Consiglio Nazionale delle mation phenomena that generate Ricerche (CNR) ha ottenuto nell’ambito della collaborazione con il Ministero dello Sviluppo Econo- a variation of the target-sensor di- mico – Direzione Generale per la Sicurezza delle attività minerarie ed energetiche dell’Ufficio nazio- stance by measuring the projection nale delle miniere per gli idrocarburi e le georisorse (DGS-UNMIG). In particolare, questo accordo si along the radar Line Of Sight (LOS) prefigge di rilevare e monitorare le deformazioni superficiali che caratterizzano le aree di particolare of the observed displacement, with interesse per la DGS-UNMIG attraverso analisi di Interferometria Differenziale Radar ad Apertura an accuracy of a fraction of the con- Sintetica (DInSAR) e modellazione multiparametrica e multifisica. La prima fornisce informazioni sulla distribuzione spaziale degli spostamenti superficiali e sulla loro evoluzione temporale, la seconda sidered SAR system wavelength. In analizza i processi geologici / geofisici che caratterizzano le aree studio. In questo lavoro presentiamo this context, starting from 2000’s, i risultati preliminari ottenuti attraverso l’analisi interferometrica che è stata effettuata utilizzando several interferometric techniques, i dati SAR acquisiti, rispettivamente, dai sensori di prima (ERS-ENVISAT) e seconda (Sentinel-1) the so-called “advanced” DInSAR generazione sull’ area dell’Emilia-Romagna (Nord Italia) e sull’intera penisola italiana. Inoltre, è stato techniques (differently from the eseguito un modello geologico-strutturale 3D del sito Cavone (Emilia-Romagna) e un modello 3D “classical” ones that produce single con il metodo degli Elementi Finiti (FEM) per simulare le dislocazioni co-sismiche associate agli eventi interferograms), based on multi- sismici M6.0 e M5.8, avvenuti il 20/05/2012 e il 29/05/2012 in Emilia-Romagna, rispettivamente. temporal approaches, have been Parole chiave: deformazione superficiale, interferometria differenziale SAR, small baseline subset, developed. These techniques effec- modellazione geofisica, terremoto del 2012 in Emilia-Romagna. tively exploit large SAR datasets made up of tens or hundreds of SAR images that are properly combined 1. Methodologies Franceschetti and Lanari, 1999) is to generate the corresponding DIn- a microwave remote sensing techni- SAR interferograms. Accordingly, 1.1. DInSAR technique que that allows investigating Earth the advanced DInSAR techniques surface deformation phenomena by allow to retrieve not only single Differential SAR Interferomet- exploiting the phase difference (in- deformation maps, but also to fol- ry (DInSAR) (Gabriel et al., 1989; terferogram) of two SAR images, re- low the temporal evolution of the

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 73-80 73 environment detected displacements by genera- analyses at two distinct spatial sca- out to be a powerful tool able to ting the time-series of deformation les, i.e. the regional and local ones. perform realistic simulations of geo- phenomena characterized by slow At the regional scale, it generates physical processes through the using dynamics (displacement rates of a mean deformation velocity maps of heterogeneous information and few cm/year). These techniques, and corresponding time-series rele- efficient mathematical methods. For compared to the in situ monitoring vant to areas that extend for several a correct definition of a FEM model, ones, such as spirit leveling, GPS or thousands of squared kilometers. the knowledge of the geological fe- inclinometers, permit the analysis At the local scale, the SBAS ap- atures of the investigated area, such of very spatially extended areas proach allows to study local defor- as rock types, tectonic structures (from some hundreds up to tens of mations that may affect buildings (seismogenic and not), rheological thousands of squared kilometers), and man-made features. Eventual- parameters, geophysical and so on, is guaranteeing a high density of mely, the SBAS algorithm allows de- very crucial. To do this, we used the asurements, thus preserving the aling with SAR data acquired by commercial finite element packa- large coverage characteristics of different radar systems nowadays ge COMSOL Multiphysics. During satellite imaging systems (Lanari et available: the ERS-1/2 and ENVI- the first year of the agreement, we al., 2004; Casu et al., 2006; Lanari et SAT sensors of the European Space have proceeded to the definition al., 2007; Manzo et al., 2012; Calò et Agency (ESA), as well as the CO- and implementation of a geological al., 2014). The advanced DInSAR SMO-SkyMed and TerraSAR-X / structural database that will be the techniques are, therefore, particu- constellations of the Italian (ASI) basis for the following forward and larly suitable to investigate spatially and German (DLR) Space Agen- the optimized models with FEM extended deformation phenomena cies, respectively (Sansosti et al., method. The chosen study area is in terms of costs/benefits, particu- 2014). More recently, it has been the portion of the Emilia Romagna larly if compared to the extension applied to SAR data collected from region (Italy) characterized by the of the investigated area. the Sentinel-1 constellation of earthquakes occurred on May 2012, Among the advanced DInSAR the Copernicus (formerly GMES) using available balanced geological techniques, IREA-CNR developed Program of the European Union. sections and interpreted seismic li- the one known as SBAS, Small Moreover, very recently a parallel nes. In particular, we performed (i) a BAseline Subset (Berardino et al., version of the SBAS approach, re- 3D lithological / structural model of 2002). It allows the analysis of the ferred to as P-SBAS, Parallel Small the Cavone area and (ii) a 3D FEM spatio-temporal characteristics BAseline Subset (Casu et al., 2014), model for simulating the co-seismic of ground displacements via the able to properly exploit distribu- dislocation of the M6.0 and M5.8 generation of mean deformation ted computing infrastructures (i.e., seismic events, which occurred on velocity maps and corresponding grid, cluster, cloud) has been deve- 20/05/2012 and 29/05/2012, respec- time-series with an accuracy of loped. It makes use of both multi- tively. about 1-2 mm/year and 5-10 mm, core and multi-node programming respectively (Casu et al., 2006). The techniques and is based on an “ad- SBAS technique relies on the use of hoc” designed distributed storage small baseline differential interfe- implementation, which is aimed at 2. Results rograms to mitigate decorrelation guaranteeing sustained scalable per- phenomena (noise effects), and on formances also for massive amounts 2.1. DInSAR results the application of the Singular Va- of data to be processed. lue Decomposition (SVD) method. In this section, we report the The latter is applied to the set of results obtained by applying the multi-looked and unwrapped inter- 1.2. Geophysical modelling SBAS technique to a set of SAR ferograms (Pepe and Lanari, 2006) data acquired from the ERS-1/2 and and allows linking independent The second research activity in- ENVISAT sensors along ascending SAR acquisition data sets separated cludes the development of a metho- orbits over the portion of the Emilia by large spatial baselines, thus in- dology for a multi-parametric and Romagna region (Italy) that inclu- creasing the number of data used for multi-physical analysis that, using des the Minerbio and Casaglia sites, the analysis. Moreover, this techni- heterogeneous data, allows a model- during the 1993-2010 time interval. que includes a step for the detection ling of the geophysical / geological Figure 1 reports (on the top) the and removal of orbital fringes and processes that characterize a study geocoded mean velocity of the sur- atmospheric phase components. In area. In this context, the numerical face deformation occurred during addition, the SBAS technique is modeling, based on the FEM (Finite the period of observations (false able to perform surface deformation Element Method) technique, turns color) superimposed on an optical

74 Dicembre 2017 ambiente image of the investigated area; the zones affected by noise effects (and for which the retrieved results are considered unreliable, see Pepe and Lanari, 2006) are properly masked out. In figure we also show (on the bottom) the plots of the temporal evolution of the surface deformation relevant to four pixels (ground pixel size of about 100 m × 100 m), identified by A, B, C and D capital letters, and located at North-West of the city of Bologna, at North of the Reno River delta, and in correspondence to Minerbio and Casa- glia sites, respectively.

Fig. 1. LOS mean deformation velocity map (cm/year), geocoded and superimposed on an optical image of the investigated area. The black square marks the reference point, located in correspondence to the Argenta town. The four plots show the temporal evolution of the LOS surface deformation relevant to four pixels located in areas of particular interest (A: North-West of Bologna city; B: North of the Reno River delta; C: Mi- nerbio site; D: Casaglia site). In each plot, the black triangles represent the ERS- 1/2 SAR images, whereas the red ones are for the ENVISAT images. The figure is relevant to the processing results of the ERS-1/2 and ENVISAT SAR data acquired along ascending orbits during the 1993-2010 time period. Mappa della velocità di deformazione in LOS, geocodificata ed espressa in cm/anno, sovrapposta ad un’immagine ottica dell’a- rea analizzata. Il quadratino nero indica il riferimento spaziale rispetto al quale sono state calcolate le misure di deformazione ed è localizzato in prossimità del centro abi- tato di Argenta. I quattro grafici riportano le serie temporali di deformazione in LOS relative a quattro punti localizzati in zone di particolare interesse (A: Nord-Ovest di Bologna; B: Nord della foce del fiume Reno; C: sito di Minerbio; D: sito di Casaglia). In ciascun plot i triangoli neri rappresentano le immagini ERS-1/2, mentre quelli rossi le immagini ENVISAT. L’immagine si riferisce all’elaborazione dei dati ERS-1/2 ed ENVI- SAT acquisiti da orbita ascendente nel periodo 1993-2010.

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Fig. 2. (a) LOS mean deformation velocity map (cm/year), geocoded and superimposed on an optical image of the entire Italian Peninsula. (b), (c) and (d) show three zoomed boxes of (a) relevant to Central Italy, Campi Flegrei Caldera and Mt. Etna Volcano, respectively. The figure is relevant to the processing results of the Sentinel-1 SAR data acquired along descending orbits during the 2014-2017 time period. (a) Mappa della velocità di deformazione in LOS, geocodificata ed espressa in cm/year, sovrapposta ad un’immagine ottica della penisola italiana. (b), (c) e (d) mostrano tre zoom della mappa (a) relativi all’Italia Centrale, la Caldera dei Campi Flegrei ed il Vulcano Etna.L’immagine si riferisce all’elaborazione dei dati Sentinel-1 acquisiti da orbita discendente nel periodo 2014-2017.

As a further step, we report the calized surface deformation patterns, structural model of the 3D Cavone preliminary results retrieved by ap- as those, for instance, associated to site (Figure 3), based on geological, plying the SBAS technique to the the seismic crisis that stroke Cen- lithological, structural and well data whole archive of SAR data collected tral Italy during the August-October available in literature (Bonini et al., from the Sentinel-1 constellation 2016 period (zoomed view in Figu- 2014, Lavecchia et al., 2015). Ca- along descending orbits over the re 2b), and the well-known ones vone site is an oil field located at the entire Italian Peninsula, during the relevant to the volcanic activity of westernmost part of the 2012 Emilia October 2014-April 2017 time in- the Campi Flegrei Caldera (zoomed Romagna seismic sequence. In or- terval. In Figure 2 we show the ge- view in Figure 2c) and Mt. Etna Vol- der to highlight a possible relation ocoded mean deformation velocity cano (zoomed view in Figure 2d) in between the ongoing surface defor- map (false color) superimposed on South Italy are clearly evident. mation and the retrieved geological an optical image of the considered horizons, we have also superimposed area in correspondence to pixels that the mean deformation velocity map are not affected by noise effects. The 2.2. Geophysical modelling obtained by using ENVISAT data presented velocity map shows some results acquired in the time interval August localized deformation patterns with 2004-October 2010 to the geology no evidence of regional scale displa- For what concerns the modelling at the Cavone well. The geological cements. On the contrary, some lo- activity, we realized a geological- data have been re-elaborated and fi-

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EW direction, coinciding with the thrusts of Inner Ferrara (or Quaran- toli) and Middle Ferrara; therefore, these structures are considered as the two seismogenetic thrusts for the FEM of the co-seismic dislocation of the two main events (May 20 and 29, 2012). The modelling results are shown in Figure 5: the maximum 3D modeled displacement is about 18 cm and focuses on the area of the Middle Ferrara structure, while in correspondence to the Inner Ferrara thrust the surface displacement is 15 cm (Figure 5a,d). In Figure 5b, a comparison between the surface displacement imaged by RadarSat-2 satellite and the modelled displacement is shown. From this comparison, it emerges that the modelling of the co-seismic dislocation along the Inner Ferrara and Middle Ferrara thrust satisfactorily succeeds in simulating the observed surface deformation pattern. Howe- ver, small areas with higher residues are also noted; they appear at the locations corresponding to the few aftershocks with Ml ≥ 5.0 not considered in the modelling procedure and that occurred in the same time Fig. 3. Geological-structural model of the 3D Cavone site (Emilia-Romagna region) su- period covered by the RSAT-2 in- perimposed on the mean deformation velocity map obtained by using ENVISAT data terferogram. acquired in the time interval August 2004-October 2010. Modello geologico-strutturale 3D dell’area del Cavone (Emilia-Romagna), sovrapposto alla mappa della velocità media di deformazione SAR ottenuta con dati ENVISAT nel periodo Agosto 2004-Ottobre 2010. 3. Conclusions nally imported into three-dimensio- of the kinematics of the seismoge- The preliminary results retrieved nal modelling software for the con- nic fault is still missing; thus, here within the framework of the IREA- struction of representative surfaces we provide a first attempt to fill this CNR/MiSE DGS-UNMIG agree- of significant stratigraphic horizons gap. In Figure 4 the main tectonic ment show that the advanced DIn- and the main tectonic structures. structures considered potentially sei- SAR techniques are an effective tool Then, we have performed a 3D smogenic for seismic events of May for monitoring and controlling the FEM model for simulating the co- 20th and 29th, 2012 are shown: the territory subject to subsidence phe- seismic dislocation of the M6.0 and thrust of Mirandola, Inner Ferrara nomena, for risk assessment and ma- M5.8 seismic events, occurring on (or Quarantoli) and Middle Ferrara. nagement, and for the resulting defi- May 2012. Although many studies In order to identify which are the nition of prevention and mitigation have been already focused on this structures to consider as responsi- strategies. They also show the po- topic (Bignami et al., 2012; Malagni- ble of the main shocks, we used the tential of 3D modelling technologi- ni et al., 2012; Pondrelli et al., 2012; seismicity from May 19 to June 30, cal development in numerical envi- Scognamiglio et al., 2012; Serpelloni 2012 with M ≥ 2.5 as a constraint. ronments that allows characterizing et al., 2012; Pezzo et al., 2013; Tizzani From this analysis we retrieved that the geophysical/geological processes et al., 2013; Chiarabba et al., 2014; the distribution of hypocenters out- related to the observed surface defor- Govoni et al., 2014), a 3D modelling lines two main clusters elongated in mations.

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Fig. 4. Structural model used for the 3D FEM model for simulating the co-seismic dislocation of the M6.0 and M5.8 seismic events which occurred on 20/05/2012 and 29/05/2012, respectively. Modello strutturale utilizzato per la modellazione 3D FEM della dislocazione co-sismica degli eventi sismici M6.0 e M5.8 del 20 e 29 maggio 2012, rispettivamente.

5. References landslide investigations through example from seismicity to crustal advanced DInSAR techniques: structure, J. Geodyn., 82, 98-109, Berardino, P., Fornaro, G., Lanari, R., The Ivancich case study, Assisi, Italy, doi:10.1016/j.jog.2014.09.003. Sansosti, E., 2002. A new Algorithm Remote Sensing of Environment, Franceschetti G., Lanari R., 1999. Syn- for Surface Deformation Monitoring vol. 142, pp. 69-82, doi:10.1016/j. thetic Aperture Radar Processing based on Small Baseline Differential rse.2013.11.003. (CRC-Press, Boca Raton, FL). SAR Interferograms. IEEE Trans. Ge- Casu, F., Manzo, M., Lanari, R., 2006. Gabriel, A.K., Goldstein, R.M., Zebker, osci. Remote Sens, 40, pp. 2375- A quantitative assessment of the H.A., 1989. Mapping small eleva- 2383. SBAS algorithm performance for tion changes over large areas: dif- Bonini L., Toscani, G., Seno S., 2014. Th- surface deformation retrieval from ferential interferometry. J Geophys ree-dimensional segmentation and DInSAR data, Remote Sensing of Res 94 (B7), pp. 9183-9191. different rupture behavior during Environment, 102, pp. 195-210, Govoni, A., et al., The 2012 Emilia sei- the 2012 Emilia seismic sequence doi: 10.1016/j.rse.2006.01.023. smic sequence (Northern Italy): (Northern Italy). Tectonophysics, Casu, F., Elefante, S., Imperatore P., Imaging the thrust fault system by 630, pp. 33-42, DOI:10.1016/j.tec- Zinno I., Manunta M., De Luca C., accurate aftershock location, Tec- to.2014.05.006. Lanari R., 2014. SBAS-DInSAR Pa- tonophysics, 2014, http://dx.doi. Bignami, C., et al., 2012. Coseismic rallel Processing for Deformation org/10.1016/j.tecto.2014.02.013. deformation pattern of the Emi- Time-Series Computation. IEEE J. Lanari, R., Lundgren, P., Manzo, M., and lia 2012 seismic sequence ima- Sel. Top. Appl. Earth Obs. Remote Casu, F., “Satellite radar interfero- ged by Radarsat-1 interferometry, Sens., vol. 7, no. 8, pp. 3285-3296. metry time-series analysis of sur- Ann. Geophys., 55(4), 789-793, Chiarabba, C., De Gori, P., Improta, L., face deformation for Los Angeles, doi:10.4401/ag-6157. Lucente, F.P., Moretti, M., Govoni, California,” Geophys. Res. Lett., Calò F., Ardizzone F., Castaldo R., A., Di Bona, M., Margheriti, L., Mar- vol. 31, no. 23, Dec. 2004, Art. ID. Lollino P.N., Tizzani P., Guzzetti F., chetti, A. and Nardi, A., 2014. Fron- 23613. Lanari R., Angeli M.G., Pontoni tal compression along the Apenni- Lanari, R., Casu, F., Manzo, M., F., Manunta M., 2014. Enhanced nes thrust system: The Emilia 2012 Lundgren, P., 2007. Application of

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Fig. 5. 3D numerical model results. (a) LOS surface displacement measured through RSAT-2 satellite. (b) Projected-LOS surface displacement model. The black stars are the two main seismic events. (c) Residuals between data and model. The blue triangles depict the larger aftershocks, with the indication of the magnitude. (d) Total surface displacement induced by the co-seismic dislocation on the thrust: Middle Ferrara (20 May event) and Inner Ferrara (29 May event). Risultati della modellazione numerica 3D. (a) spostamento superficiale misurato con il satellite RSAT-2 in LOS. (b) spostamento modellato e proiettato in LOS. Le stelle nere sono i due eventi sismici principali. (c) residuo tra dato e modello. I triangoli blu rappresentano gli aftershocks principali, con indicazione della magnitudo (d) Spostamento superficiale totale indotto dalla dislocazione co-sismica dei due thrust: Middle Ferrara (evento del 20 maggio) e Inner Ferrara (evento del 29 maggio).

the SBAS-DInSAR technique to Malagnini, L., Herrmann, R.B., Munafo, 169, pp. 1463-1482, doi: 10.1007/ fault creep: a case study of the I., Buttinelli, M., Anselmi, M., Akinci, s00024-011-0403-2. Hayward fault, California, Remo- A. and Boschi, B., 2012. The 2012 Pepe, A. and Lanari, R., “On the te Sensing of Environment, vol. Ferrara seismic sequence: Regio- extension of the minimum cost 109, 1, pp. 20-28, doi: 10.1016/j. nal crustal structure, earthqua- flow algorithm for phase unwrap- rse.2006.12.003. ke sources, and seismic hazard, ping of multitemporal differential Lavecchia, G., De Nardis R., Costa Geophys. Res. Lett., 39, L19302, SAR interferograms,” IEEE Trans. G., Tiberi L., Ferrarini F., Cirillo D., doi:10.1029/2012GL053214. Geosci. Remote Sens., vol. 44, no. Brozzetti F., Suhadolc, P., 2015. Was Manzo, M., Fialko, Y., Casu, F., Pepe, 9, pp. 2374-2383, Sep. 2006. the Mirandola thrust really involved A., Lanari, R., 2012. A quantitative Pondrelli, S., Salimbeni, S., Perfetti, P. in the Emilia 2012 seismic sequen- assessment of DInSAR measure- and Danecek, P., 2012. Quick regio- ce (Northern Italy): Implications on ments of interseismic deforma- nal centroid moment tensor so- the likelihood of triggered seismicity tion: the Southern San Andreas lutions for the Emilia 2012 (Nor- effects. Boll. Geof. Teor. Appl., 56, Fault case study, Pure and Applied thern Italy) seismic sequence, Ann. pp. 461-488. Geophysics (PAGEOPH), vol. Geophys., 55, doi:10.4401/ag-6146.

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Scognamiglio, L. et al., 2012. Pianura Pezzo, et al., Coseismic Deforma- impacting the analysis of ground Padana Emiliana seismic sequence: tion and Source Modeling of deformation. International Journal Locations, moment tensors and the May 2012 Emilia (Northern of Applied Earth Observation magnitudes, Ann. Geophys., 55, Italy) Earthquakes. Seismologi- and Geoinformation, 28, 1-11, 549-559, doi:10.4401/ag-6146. cal Research Letters Volume 84, doi:10.1016/j.jag.2013.10.007 Serpelloni, E., et al., 2012. GPS Number 4 July/August 2013 doi: Tizzani, P., et al., 2013. New insights observations of coseismic de- 0.1785/0220120171. into the 2012 Emilia (Italy) sei- formation following the May Sansosti, E., Berardino, P., Bonano, smic sequence through advan- 20 and 29, 2012, Emilia seismic M., Calò, F., Castaldo, R., Casu, F., ced numerical modeling of events (Northern Italy): Data, Manunta, M., Manzo, M., Pepe, A., ground deformation InSAR me- analysis and preliminary models, Pepe, S., Solaro, G., Tizzani, P., Zeni, asurements, Geophys. Res. Lett., Ann. Geophys., 55(4), 759-766, G., and Lanari, R., (2014). How 40, 1971-1977, doi:10.1002/ doi:10.4401/ag-6168. new generation SAR systems are grl.50290.

Acknowledgments This work was carried out within the framework of the IREA-CNR/MiSE DGS-UNMIG agreement. Moreover, it was partially supported by the I-AMICA project (Infrastructure of High Technology for Environmental and Climate Moni- toring-PONa3_00363) that provided the IREA-CNR with the remote sensing data processing and storage system. Sentinel-1 SAR data are copyright of Copernicus (2016), the DEMs of the Italian territory are acquired from the SRTM archive.

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N. Cenni* Unconventional methods S. Gandolfi* P. Macini* for offshore subsidence L. Poluzzi* monitoring L. Tavasci* * Università di Bologna, DICAM, Dipartimento di Ingegneria Civile, This paper provides an overview of some unconventional methods currently used or under testing Chimica, Ambientale e dei Materiali, for the monitoring of offshore subsidence due to underground fluids withdrawal. Many well-tested Bologna and reliable tools are today available to monitor onshore subsidence. Conversely, seafloor deformations around offshore Oil and Gas reservoir in production are quite difficult to estimate, and almost all the proposed methods use an indirect approach. The methods here described are based on the measurement of time and spatial variation of physical measurable quantities (water column metry; each method has its own ver- pressure, sonar signals, tilts, deformation of cables) to monitor seafloor subsidence. The accuracy tical accuracy and horizontal resolu- attainable on the vertical deformation depends on the method and typically ranges from a few cm tion. A key aspect of these techniques to some mm. Keywords: offshore subsidence, accuracy, pressure, tiltmeter, deformation cable. is the survey methodology. In some cases, the measurements are carried Metodi non convenzionali per il monitoraggio della subsidenza. Il lavoro analizza alcuni out only during dedicated field cam- metodi attualmente utilizzati, o in fase di sperimentazione, per monitorare il fenomeno della subsi- paigns, while in other cases the sen- denza in aree offshore interessate da produzione di fluidi del sottosuolo. Oggi sono disponibili molti sors are permanently installed on the strumenti ben testati ed affidabili per monitorare la subsidenza a terra. Viceversa, le deformazioni seafloor, providing a large number of del fondale marino che circonda i giacimenti di idrocarburi in produzione sono difficili da stimare, information, sometimes even in real e quasi tutti i metodi proposti usano un approccio indiretto, come la misura della pressione della or quasi-real time. In the following colonna d’acqua, segnali sonar, inclinazione di uno o più pendoli, o la deformazione di cavi posati sul chapters, we analyse some methods fondale marino. La precisione sulla misura della deformazione verticale dipende dal metodo utiliz- described in the recent scientific lite- zato, e può variare da pochi cm a qualche mm. rature, whose data and performances, Parole chiave: subsidenza offshore, accuratezza, pressione, Inclinometria, cavo di deformazione. however, may not be fully disclosed or published so far, highlighting in particular the vertical accuracy and 1. Introduction applicable, with exception of tiltme- horizontal resolution of each “uncon- ter arrays. GNSS and SAR can give ventional” method, along with their Underground fluids withdra- information about the vertical mo- possible future developments. wal causes pore pressure decline, vements of the offshore infrastructu- which increases the effective state res, but are not applicable to seafloor of stress on the reservoir rock. Over subsidence monitoring. 2.1. Interferometric Synthetic time, and depending upon the rock Aperture Sonar (SAS) strength, the effective stress increase can induce reservoir compaction Seafloor subsidence can be esti- and possibly land subsidence. Geo- 2. Seafloor subsidence mated by comparing two or more mechanical modelling (Codegone monitoring methods seabed maps obtained with a Mul- et al. 2016; Gambolati et al. 1991; tiBeam Echo-sounder (MBE) or by Geertsma 1973) and field measure- Seafloor subsidence occurring du- an Interferometric Sidescan Sonar ments proved that the subsidence ring offshore hydrocarbon produc- (SSS). Unfortunately, both techno- bowl could extend several km from tions seems likely that it can be mo- logies are limited by poor along-track the production sites. Many tools are nitored by several unconventional resolution (Sæbø et al. 2007; Sæbø available to monitor onshore subsi- methods developed in recent times, 2010 and reference therein). The dence, such as spirit levelling, per- although most of them are still in an Interferometric Synthetic Aperture manent or semi-permanent GNSS experimental stage. Different me- Sonar (InSAS) technique can remo- (Global Navigation Satellite Sy- thods have been proposed to monitor ve this constrain and provides high- stem), extensometers, tiltmeter ar- offshore subsidence, which are based resolution seafloor maps with range rays and Synthetic Aperture Radar on measurement of water column independent resolution (Barclay et (SAR). As for offshore Oil and Gas pressure, sonar signals, deformation al. 2005; Sæbø 2010). SAS, likewise production, these methods are not of cables fixed to the seafloor or gravi- SAR, is a system where the along-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 81-84 81 environment track resolution is independent of equipped with three pressure gauges, and offshore areas. This device me- range, and high-resolution images gravimeters and electronics for remo- asures very small inclination rates, can be obtained without the need for te control (Sasagawa et al. 2003). The which are far easier to measure than a physically large array (Griffithset al. benchmarks were located outside and the inclination itself. In particular, 1997). Therefore, SAS can provide inside the expected subsidence bowl. tilt measurements define the slope maps that ideally are independent During the survey, the ROV was pla- of ground movements. The vertical of ranges and frequencies. InSAS is ced atop of the benchmarks to mea- displacement can be estimated by an extension of SAS. It can produ- sure pressure, temperature and gra- integrating the slope measurements ce a height map to complement the vity. The same measurements were taken from several tiltmeters. Since conventional SAS backscattered in- simultaneously and independently a constant of integration is required, tensity imagery (Barclay 2006). The repeated at benchmarks outside the one point in the array is defined as principal applications of this method subsidence bowl, to set the reference the zero point, i.e., a steady referen- are the monitoring of objects laying pressure records and thus to correct ce against which all other inclina- on the seafloor (archaeological struc- the temporal variations of seafloor tion rates are measured (Davis et al. tures, wrecks, offshore installations, waterpressure measurements. These 2000). The installation of tiltmeters etc.) and the elaboration of relia- variations could be caused by several in the seafloor is not always an easy ble high-resolution seafloor maps. reason such as ocean tides, changes task, since it requires the drilling of In order to obtain a high resolution in atmospheric pressure, wind setup, shallow and stable boreholes 5 to 12 seafloormap with InSAS, the obser- possible dynamic effects caused by m deep. Furthermore, the monito- vations acquired during the survey fluid flow around the instruments, ring of large fields requires for the in- are processed by complex filtering water density fluctuations,etc . (Sten- stallation of a large number of tiltme- procedures. The maps obtained can vold et al. 2006). The ROV pressure ters in order to obtain a regular and be characterized by a horizontal reso- surveys, corrected using the reference adequately spaced array. Cost and in- lution ranging from few cm to up to records, can be converted to depths stallation issues can made impracti- hundreds of m, and a vertical accu- by using the average density profile cal to use large tiltmeter arrays in the racy of some cm (Sæbø et al. 2007). measured at certain depth intervals offshore environment. Nevertheless, The vertical accuracy depends on the during the same survey. The seafloor when a tiltmeter array is installed, it processing parameters, such as the subsidence can be evaluated compa- can provide quasi-continuous high number of pixels used in the filtering ring the depths estimated using data precision data of the seafloor move- phase, seabed depth, signal-to-noise acquired in two or more surveys, ments. Stenvold et al. (2006) suggest ratio and filter size (Sæbøet al. 2007). under the constraint that the avera- that movements in the order of 10-5 If the values of these parameters are ge depth difference for the stations m may be detected by a tiltmeter ar- changed in order to improve the ver- located outside the subsidence bowl ray. Fabian and Villinger (2007) de- tical accuracy, this results in a reduc- is zero (Stenvold et al. 2006). A sub- veloped an ocean bottom tiltmeter tion of the horizontal resolution. sidence accuracy of few cm (and up equipped with two sensor: an absolu- to 1 cm) has been achieved during te accelerometer and a biaxial bubble the monitoring of the above gas field tilt with a signal resolution of about 2.2 Seafloor water pressure and CO2injection site. A similar me- 1.0 µrad. It was tested to monitor the thod was used by other researchers movements of a hydrothermal vent A possible method to monitor sea- (Chadwick et al. 2006) in order to field located in the Mid-Atlantic floor subsidence is based on seafloor monitoring the vertical deformation ridge. Anderson et al. (1997) stu- water column pressure monitoring. of an active submarine volcano loca- died the deformation of a submari- Water pressure can be converted ted at depths ranging between 1500 ne volcano by a tiltmeter array, and to depths by using an average den- and 1700 m. Here, an accuracy of a attained an accuracy of about 10 sity profile, and the subsidence can few cm was obtained, close to the one µrad for the tilt measurements, that be estimated comparing the results obtained by Stenvold et al. (2006), corresponds to an accuracy of a few obtained during two or more surveys. where the benchmarks depth ranges mm in the vertical displacement. Stenvold et al. (2006) utilized this from 80 to 350 m. Recent studies carried out by Eni technique to investigate the seafloor oil company (Miandro et al. 2017, subsidence around a gas field and a 2015) indicate the tiltmeter array as CO2 injection site, both located in 2.3. Tiltimeter arrays a promising method to monitor sea- the North Sea. In particular, water floor subsidence around offshore Oil pressure was measured atop of dedi- Tiltmeter is the only tool that and Gas platforms. A schematic of cated seafloor benchmarks using a can be used to complement subsi- the installation is shown in Figure 1, Remotely Operated Vehicle (ROV) dence monitoring in both onshore left. The system is completed with a

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Fig. 1. Left: Schematic of a seafloor tiltmeter array. Center: Seafloor monitoring via cable equipped with fiber optic sensors for strain measurements. Right: as above, fiber optic sensors for pressure monitoring; the small ellipses in the cable indicates the pressure measurement points. All these systems are proposed in Miandro et al. 2015, 2017. Figure credits: Miandro et al. 2015. A sinistra, schema di un array di tiltmetri a fondo mare. Al centro: monitoraggio del fondale con cavo munito di sensori a fibra ottica per la misura della deformazione. A destra: come sopra, sensori a fibra ottica per il monitoraggio della pressione; le piccole ellissi indicano i punti di misura. Questi sistemi sono proposti e descritti in Miandro et al. (2015, 2017), da cui sono tratte tutte le figure. permanent GNSS station located on 1 m depth, whereas data acquisition time-dependent gravity signal over the platform, while the tiltmeters are and the control unit is placed aboard the reservoir. Among all of the ge- fixed to the seabed along a determi- a production platform equipped with ophysical monitoring methods, ned direction and spacing and are a GNSS permanent station. Feasibili- gravimetry allows the detection of connected to the platform with an ty studies have been carried out with mass balance variations due to water umbilical cable, allowing to monitor a cable equipped with fiber optic sen- encroachment. Seafloor subsidence seafloor tiltsin real or quasi real-time. sors. The seafloor movements can be can also contribute to gravity signals detected in two ways: 1) By the defor- as well as the changing of density mation induced on the shape of the distribution (Sasagawa et al. 2003). 2.4. Instrumented Cables fixed cable, detected by the fiber optic sen- Therefore, in order to use gravimetry on the Seafloor sors (Figure 1, center). 2) By a liquid for reservoir monitoring, the subsi- filled cable: when a section of the ca- dence effect must be previously eva- Offshore subsidence can be moni- ble moves along the vertical, the pres- luated by other techniques. Conver- tored by either “intelligent” pipes or sure changes along this section, and sely, if a detailed information about cables fixed on the seafloor and con- can be measured by the fiber optic the subsurface deformations is avai- nected to a control system. Each cable sensors or other tools (Figure 1, right, lable, for example in depleted reser- investigates movements only along Miandro et al. 2017, 2015).The same voirs, the gravimetry measurements one direction and, in order to obtain authors suggest a third tool, which can be used in order to monitor the a complete monitoring of the subsi- is an upgrade of a horizontal profile subsidence phenomena (Supriyadi dence bowl, several pipeline must be gauge, today used to monitor hori- et al. 2017). This observation must installed. These systems can provide zontal bending of dams, harbours and have an accuracy of 10-8 ms-2 and the monitoring of seabed movement- airport runways. The measurement are characterized by a looping mea- sin real or quasi-real time, which principle is based on the estimation surements method (Supriyadi et al. can be also used to monitor subsur- of the pressure of a liquid column ac- 2017). The current time-lapse ac- face deformation sources, reservoirs ting on several measurement points. curacy in seafloor gravity is at level characteristics and production para- The standard tools operate at atmo- of about 10-8 ms-2 (Vatshelle at al. meters. Eni oil company is actively spheric conditions, thus the upgrade 2017), that is theoretically enough involved in this field of study, with a concerns the design of a subsea tool, for monitoring seafloor subsidence. research program for the construction by using a close circuit and a compen- of an “intelligent” cable able to mea- sator specifically designed for subsea sure seafloor subsidence in quasi-real conditions. time with an accuracy of about 5 mm 3. Conclusions (Miandro et al. 2017, 2015). The maximum length of the cable should be 2.5. Gravimetry The paper reviews some methods about 3 km, with a maximum spacing described in the recent scientific li- between the measurements points During petroleum production, terature about unconventional me- ranging from 100 to 200 m. The cable water can replace oil or gas in the thods to monitor offshore subsiden- must be placed in a trench of about reservoir. This process generates a ce. In some cases, the techniques are

Dicembre 2017 83 environment are only at a theoretical level and C.G., 2006. Vertical deformation monitoring system for offshore field application is undergoing and/ monitoring at Axial Seamount sin- applications: technology scouting or data are not yet available, there- ce its 1998 eruption using deep- and feasibility studies. Proc. IAHS, fore the reported accuracies are no- sea pressure sensors. Journal of pp. 372, 323-330. minal. In other cases, the vertical Volcanology and Geothermal Re- Miandro, R., Dacome, C., Mosconi, A., displacement precision depend on search, Vol.150, pp. 313-327. Roncari, G., 2017. An innovative the method adopted and the en- Codegone, G., Rocca, V., Verga, F., Coti, approach for offshore subsidence vironmental conditions where the C., 2016. Subsidence Modeling Va- monitoring: technology scouting, measurements have been performed. lidation Through Back Analysis for feasibility studies and realization. In Some authors (Anderson et al. 1997; an Italian Gas Storage Field, In: Ge- Proc. 13th OMC, Ravenna, Italy. Stenvold et al. 2006) indicate an ac- otechnical and Geological Engine- Sæbø, T.O., Callow, H.J., Hansen, R.E., curacy of some mm for tiltmeter ar- ering Springer, pp. 1749-1763. Langli B. and. Hammerstad, E.O., rays located on the seafloor. Miandro Davis, E., Wright, C., Demetrius, S., 2007. Bathymetric Capabilities of et al. (2015, 2017) designed methods Choi, J., and Craley, G., 2000. Pre- the HISAS Interferometric Syn- based on different physical mea- cise Tiltmeter Subsidence Moni- thetic Aperture Sonar. In: OCEANS surable quantities with a nominal toring Enhances Reservoir Mana- 2007, Vancouver, BC, 2007, pp. accuracy of 5 mm. Subsidence mo- gement. Paper SPE 62577, SPE/ 1-10. nitoring precision using SAS depen- AAPG Western Regional Meeting, Sæbø, T.O., 2010. Seafloor Depth ds on some parameters used in data Long Beach (CA). Estimation by means of Interfe- processing, and can achieve acenti- Fabian, M. and Villinger, H., 2007. The rometric Synthetic Aperture So- metriclevel (Sæbø et al. 2007). An Bremen ocean bottom tiltmeter nar. Ph Thesis, UIT, University of accuracy of a few cm (up to 1 cm) (OBT) – a technical article on a Tromsø, Norway. has been achieved during subsiden- new instrument to monitor deep Sasagawa, G.S., Crawford, W., Eiken, ce monitoring of a gas field and CO2 sea floor deformation and seismi- O., Nooner, S., Stenvold, T., and storage with measurements of water city level. Marine Geophysical Re- Zumberge, M.A., 2003. A New column pressure (Chadwick et al. search, Vol. 28. Seafloor Gravimeter. Geophysics, 2006; Stenvold et al. 2006). The evi- Gambolati, G., Ricceri, G., Berto- 68(2), pp. 544-553. dences from this study suggest that ni W., Brighenti, G., Vuillermin E., Stenvold, T., Eiken, O., Zumberge, the accuracy ofseafloor subsidence 1991. Mathematical simulation of M., Sasagawa, G., and Nooner, monitoring depends on the specific the subsidence of Ravenna. Water S., 2006. High-Precision Relative method, and ranges from a few cm Resources Research, Vol. 27, pp. Depth and Subsidence Mapping up to some mm. 2899-2918. from Seafloor. Water Pressure Geertsma J., 1973.A basic theory of Measurements. SPE Journal, 11-3. subsidence due to reservoir com- Supriyadi, Khumaedi, Nur Qudus, paction: the homogeneous case. Pradana Adi Wibowo, and Dino References Verh. Kon. Ned. Geol. Mijnbowk Gunawan., 2017. Strategy imple- Gen., Vol. 23, pp. 43-62. mentation time lapse microgravity Anderson, G., Constable, S., Staudigel, Griffiths, H.D., Rafik, T.A., Meng, Z., method for monitoring subsiden- H., and Wyatt, F.K., 1997. A Seaflo- Cowan, C.F.N., Shafeeu, H., and ce. AIP Conference Proceedings or Long-Baseline Tiltmeter, Journal Anthony D.K., 1997. Interferome- 1818, 020057. of Geophysical Research, Vol. 102, tric synthetic aperture sonar for Vatshelle, M., Glegola M., Lien M., No- pp. 20269-20285. high-resolution 3-D mapping of the ble T., Ruiz H., 2017. Monitoring the Barclay, P.J., Hayes, M.P., and Gough, seabed. IEE Proc-Radar, Sonar Na- Ormen Lange Field with 4D Gra- P.T., 2005. ML estimation of sea- vigation, Vol 144, No 2, pp. 96-103. vity and Seafloor Subsidence. 79 floor topography using multi-fre- Miandro, R., Dacome, C., Mosconi, th EAGE Conference & Exhibition, quency synthetic aperture sonar. A., Roncari, G., 2015. Subsidence Paris, 12-15 June 2017, pp. 1-5. In: Europe Oceans, 2005, Brest, France, Vol. 1, pp. 579-584. Barclay, P.J., 2006. Interferometric Syn- thetic Aperture Sonar Design and Performance. Ph.D. Thesis, Univer- Acknowledgement sity of Canterbury, Christchurch, The study was carried out in the framework of the Research Project “Network New Zealand. for Offshore Safety”, funded by the Italian Ministry of Economic Development, Chadwick, W.W. Jr, Nooner, S., Zum- Directorate-General for Safety of Mining and Energy activities, National Mining berge, M., Embley, R.W. and Fox, Office for Hydrocarbons and Georesources (DGS-UNMIG).

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C. Benetatos* Guidelines for the study G. Codegone* C. Deangeli* of subsidence triggered by G. Giani* A. Gotta* hydrocarbon production F. Marzano* V. Rocca* This study was carried out by the SEADOG Research Center at Politecnico di Torino (Italy). The pur- F. Verga* pose of this work was to evaluate which complexity degree would be required to reliably approach a subsidence study for different scenarios. The study was based on sensitivity analyses which were * Politecnico di Torino DIATI, performed using a series of 3D synthetic numerical models of which the structural characteristics Torino, Italy and geological and mechanical properties were based on available public data of onshore and offshore hydrocarbon fields in Italy. An array of simulations, both one-way and two-way coupled, were carried out to assess the magnitude and extension of subsidence potentially induced by hydrocarbon production. The results allowed the calculation of subsidence indices defined as the rate the latter marks off the area beyond of compaction propagation (i.e., the ratio between the maximum surface displacement and the which surface displacement is null or maximum reservoir compaction) and as the rate of volume loss (i.e. the ratio between the volume negligible. of the subsidence bowl or cone and the volume variation of the reservoir). These indices together The scope of this work was to with the degree of the underground systems’ heterogeneity led to the definition of the Intact Rock assess which degree of complexity Qualitative Subsidence Index (IRQSI), upon which the needed complexity degree of a subsidence would be required to approach a sub- study can be discerned. sidence study under different scena- Keywords: subsidence, compaction, hydrocarbon production, safety, mechanical analysis, intact rock. rios and which parameters are more Linee guida per lo studio della subsidenza indotta dalla produzione di idrocarburi. critical to achieve reliable results. Questo studio è stato condotto dal Centro di Ricerca SEADOG presso il Politecnico di Torino (Italia). The study was based on the execu- Lo scopo del presente lavoro è stato quello di valutare il grado di complessità opportuno per affron- tion of sensitivity analyses which tare uno studio di subsidenza in modo affidabile. Lo studio è stato basato su analisi parametriche were made using an array of 3D syn- eseguite implementando una serie di modelli numerici sintetici tridimensionali le cui caratteristiche thetic numerical models. The nu- strutturali e le cui proprietà geologiche e meccaniche sono state ricavate sulla base di dati pubblici merical models were defined on the relativi a giacimenti di idrocarburi a terra e a mare ubicati in Italia. Le simulazioni, condotte con basis of the available information approccio sia di tipo one-way coupling sia di tipo two-way coupling, hanno permesso di valutare about the geological and geometric l’entità e l’estensione del cono di subsidenza potenzialmente indotta dalla produzione di idrocarburi. characteristics and of the production Grazie ai risultati ottenuti è stato possibile calcolare gli indici di subsidenza, definiti come il tasso di history of both onshore and offshore propagazione della compattazione (cioè il rapporto tra lo spostamento superficiale massimo e la Italian hydrocarbon fields. This in- massima compattazione del giacimento) e il tasso di perdita di volume (cioè il rapporto tra il volume del cono di subsidenza e la variazione di volume del giacimento). Questi indici, insieme al grado formation was collected from tech- di eterogeneità dei sistemi sotterranei, hanno portato alla definizione dell’Indice di Subsidenza Qua- nical reports and public data and litativo della Roccia Integra (IRQSI), in base al quale è possibile discriminare il grado di complessità organized into a comprehensive da- necessario per valutare la subsidenza in funzione delle caratteristiche del sistema oggetto di studio. tabase; then, it was used to define a Parole chiave: subsidenza, compattazione, produzione di idrocarburi, sicurezza, analisi meccanica, reference regional-scale stratigraphy roccia integra. (up to 5 km deep), representative of the Po Valley and Adriatic regions, as well as an appropriate range of va- 1. Introduction Hydrocarbon production induces lues for the most relevant rock pro- a pressure variation in the reservoir perties. The aim of this paper is to provide and the surrounding aquifer, when The assessment of induced subsi- criteria for the forecast of subsiden- present, which in turn triggers com- dence for different scenarios was pos- ce induced by hydrocarbon produc- paction of the reservoir rocks; this sible by the use of the finite element tion – or storage – by the definition compaction propagates to the sur- numerical method (FEM) imple- of guidelines, particularly in relation face through the overburden rocks mented in a software. The coupling to the Italian offshore context. The and causes subsidence. Vertical di- between fluid-dynamic and geome- study was carried out by the SEA- splacements at the surface define chanical analysis was carried out DOG Research Center at Politec- a subsidence bowl or cone (Fjær et with an explicit approach (also called nico di Torino within the activities al., 2008), which can be defined ge- one-way coupling) (Tran et al., 2005) regarding the assessment of offshore ometrically in terms of maximum in which pressure variations induce safety. vertical displacement and radius; changes in the stress state and defor-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 85-96 85 environment mation of the porous medium, but hydrocarbon fields (Figure 1) and tify a suitable range of values for the the latter does not affect the dynamic information related to their produc- geometric characteristics and for response of the system. Simulations tion history was derived from tech- the petrophysical and mechanical with an iterative (two-way coupling) nical reports, scientific publications properties, (2) select a set of strati- approach (Tran et al., 2005) were also and well logs at 1:1000 scale availa- graphic sequences representative of carried out to evaluate the combined ble on the UNMIG website (Ufficio the Italian setting, and (3) set up the effects of porosity (thus volume) and Nazionale Minerario per gli Idrocarburi input of the numerical geomechani- permeability variations. e le Georisorse – VIDEPI project @ cal simulations carried out to assess http://unmig.sviluppoeconomico. subsidence induced by hydrocarbon gov.it). production. The study refers to gas All the information was integra- reservoirs because most Italian reser- 2. Database ted into a comprehensive databa- voirs are gas-bearing. se and used to define synthetic 3D Information regarding the struc- models representative of the most tural, geometric, lithological, pe- common Italian reservoir forma- trophysical and mechanical cha- tions. Qualitative and quantitative 3. Considerations on faults racteristics of nearly 250 Italian information was used to (1) iden- During the operations of fluid production or injection, pressure and stress state of the hydrocarbon- bearing formation and surrounding rocks is altered. Structural discontinuities can have an impact on pressure and stress distribution and thus on subsidence phenomena. Fur- thermore, faults and fractures could potentially be reactivated by a variation of normal and shear stresses. A systematic assessment of the impact of faults and fractures on subsidence phenomena was not possible because discontinuities represent heterogeneities which may or may not exist in rocks and if present should be characterized in terms of geometry, orientation, mechanical characteristics. Faults are conventional- ly defined as discontinuity surfaces or narrow zones with detectable shear displacement (Fossen, 2010; Davis et al., 2012); however, in nature they often consist of fractured rock material, they can include subsidiary brittle structures and have a thickness that can vary both laterally and ver- tically (Childs et al., 2009; Fossen, 2010; Matonti et al., 2012; Choi et al., 2016). In general faults have high internal heterogeneity and complexity and are typically characterized by mechanical and petrophysical properties that differ from the surrounding intact rocks and that can Fig. 1. Location of examined Italian offshore and onshore fields. strongly vary even along the same Posizione dei campi italiani offshore e onshore analizzati. fault segment according to the litho-

86 Dicembre 2017 ambiente logical/structural characteristics and characteristics of the models, such as ce extends 5 km in the depth from internal complexity of the deforma- the regional stratigraphy, the reser- the seabed (set at 50 m ss) and inclu- tion zone (Scholz, 1987; Fischer and voir/caprock lithology and geomet- des from top to bottom (Fig. 2): Knipe, 2001; Fredman et al., 2007; ry, the petrophysical and mechanical 1. an interval of mostly sandy layers Faulkner et al., 2010). rock properties, were defined on the representing the late Pliocene – Reactivation of existing discon- basis of the information integrated Quaternary marine-delta and the tinuities induced by hydrocarbon into the database. overlying recent marine deposits production or injection was out of (average thickness: 450 m); the scope of this work. However, it 2. an interval of alternating sand is worth mentioning that the reacti- 4.1. Geological sequence and clay layers representing the vation models proposed in the lite- Pliocene turbiditic sequence rature usually assume that the fault The regional stratigraphic setting (average thickness: 1500 m); correspond to a discontinuity plane was reconstructed by cross-referen- 3. an interval of marl representing consisting of two contact surfaces, cing the available scientific and the middle Eocene – late Mioce- and shear strength is described with technical literature (Pieri & Grop- ne outer platform and slope depo- Coulomb’s criterion, without consi- pi, 1981; Casero, 2004; Carruba et sits (average thickness: 1000 m); dering the contribution of cohesion. al., 2006; Bertello et al., 2008, 2010; 4. an interval of carbonate deposits In spite of the simplicity of Cou- Ghielmi et al., 2010, 2013; Vezzani representing the early Triassic – lomb’s criterion one of the uncer- et al., 2010; Casero & Bigi, 2013; Jurassic dolomite and the early Ju- tainties found in the analysis of fault Cazzini et al., 2015). A simplified re- rassic – middle Eocene limestones reactivation is the value of the fric- gional-scale stratigraphy consisting (average thickness: 2000 m). tion angle. In fact, the friction angle of continuous and homogeneous ge- The reservoir is represented by a represents a phenomenological pa- ological formations representative of sandy natural-gas bearing interval, rameter, which takes into account the Po Valley and Adriatic regions 100 m thick, belonging to the turbi- all the complex characteristics and was assumed. ditic sand-clay alternation. The ca- behavior exhibited by faults during The reference geological sequen- prock consists of a 20 m continuous shear processes. The values of the friction angle in laboratory tests are affected by the scale effects affecting strength when going from decime- tric surfaces to large natural surfaces on site. Byerlee (1978) analysed the results of shear tests carried out on discontinuities in rocks of various li- thologies and concluded that at high normal stresses the friction angle is independent of the type of rock. Ba- sed on these studies, the scientific literature indicates that the friction angle of a fault is likely to be between 30° and 40°. However, the presence of illite and montmorillonite can significantly reduce shear resistance. For the reasons outlined above the formation was considered as intact rock material (Brady & Brown, 2004).

Fig. 2. Schematic stra- 4. Subsidence modelling of tigraphy (not to scale) of the 3D geological intact rocks model. Schema stratigrafico An array of 3D models was defi- (non in scala) del model- ned to carry out the simulations. The lo geologico 3D.

Dicembre 2017 87 environment clay layer belonging to the same tur- overall thickness was 5 km. Several constitutive models have biditic sequence. The reservoir embedded in the been proposed in the literature for model is located in an axially sym- the prediction of compaction and metric anticline trap (as in the subsidence, from the simple linear 4.2. Geometric modelling and example Figure 4) and is characte- elastic law to the elasto-plastic and characterization rized by average values of the petro- visco-elasto-plastic laws. physical and mechanical parameters. The most general and frequen- The model dimensions were such However, reservoir size was modified tly used failure criterion is Mohr to properly describe the reservoir and to include sensitivities on the vo- Coulomb (Fjær et al., 2008). Fur- the surrounding volumetric aquifer lume of hydrocarbons originally in thermore, the Modified Cam Clay (which varied in the different exami- place. The aquifer is bounding the model (Roscoe & Burland, 1968), ned scenarios) and to guarantee that reservoir laterally when present. specifically formulated for clays, has undisturbed boundary conditions A 10-year field production histo- been used over the last years for the could exist. As a consequence, mo- ry was simulated for all studied cases analysis of the mechanical response del dimensions were set horizontally to induce pressure disturbance and of sedimentary rocks (e.g. Cuss et al., in the order of dozens of kilometers to reach a final gas recovery factor 2003; Capasso & Mantica, 2006; Fir- (as in the example Figure 3) and the equal to 65%. me et al., 2014). Even though the Mohr Coulomb elasto-plastic model is undoubtedly a very simple law, it has the advantage of requiring only the knowledge of cohesion, friction angle and elastic parameters of the rock. Since this study had a practical purpose, i.e. the assessment of the complexity degree required to approach a subsidence study and of the parameters having a major impact on results, the stress- strain response of the formations was investigated using a yield function represented by the Mohr-Coulomb failure criterion. Simulations adopting the Modified Cam Clay model Fig. 3. Example of 3D numerical model for geomechanical simulations. with different OCR values were car- Esempio di modello numerico 3D per simulazioni geomeccaniche. ried out to evaluate the differences

Fig. 4. Top geometry of the reservoir. Geometria del top del giacimento.

88 Dicembre 2017 ambiente with the Mohr-Coulomb failure cri- For the Poisson’s coefficient typical the production-related subsidence. terion only for a subset of cases for values for rocks and soils were used The geological parameters descri- comparison purposes. (Gercek, 2007). be the geometric characteristics of Mechanical simulation results the reservoir (depth, shape, volume) refer to maximum variation of the and of the aquifer, when it is present formation static pressure (or deple- 4.3. Simulations (radius) (Figure 5; Table 1). tion) which, under the assumption The mechanical parameters (Ta- of a homogeneous and isotropic po- The simulations were performed ble 1) include the strength (c’, ϕ’) rous medium and in the absence of to investigate the impact of geolo- and deformation (E’, ν’) properties viscous deformation (or creep), re- gical and mechanical parameters on of rocks and soils, the initial stress presents the most critical condition for subsidence (Hettema, 2002). The compaction coefficient (or uniaxial compressibility), Cm, changes with depth. For the North Adriatic formations the uniaxial compressibility, Cm, is correlated to the effective vertical stress (σ’v) according to (Baù et al., 2002): – 2 –1.1347 –1 Cm = 1.0044 · 10 σν’ [MPa ] (1) The uniaxial compressibility is related to the static Young’s modulus, E’s, and to Poisson ratio, ν’, by the following: 11() ()12 C (2) Fig. 5. Scheme of the geometric variables. H : total thickness of the hydrocarbon- m E 1 res s bearing formation; Rres: reservoir radius; Raq: aquifer radius; d: depth. Schema delle variabili geometriche. Hres: spessore totale della formazione mineralizzata; Consequently, in the numerical Rres: raggio del giacimento; Raq: raggio dell’acquifero; d: profondità. analyses for subsidence evaluation, the static Young’s modulus (E’s) of Tab.1. Analysed parameters and intervals. the sand-clay sequence was defined Parametri analizzati e relativi intervalli indagati. by combining eq. (1) and eq. (2): Parameters Interval Units ()11 () 2 Depth [d] 300-3500 m E 4 s 1 (3) Shape factor [H /R ] 0.01-0.10 - 1 Geological res res 4 9 3 21 .1347 Volume [V] 0.8-21.4 10 m sc 1. 00444 10 Aquifer [R /R ] 1-20 - The numerical analyses were also aq res made considering a dynamic Young’s 1.7 (E’s)-6.9 (E’d) Young’s Modulus(1) [E’] E’ = f(ε ) GPa modulus (E’d) defined by the inter- v pretation of well logs (both density (εv = vertical deformation) and sonic). Moreover, a sensitivity 0.20-0.45 analysis was performed accounting Poisson’s coefficient [ν’] ν’ = f(z, γ) - for the variation of Young’s modulus (z = depth; γ = lithology) Mechanical as a function of the axial strain (E’ = Cohesion (1) [c’] 0.6-1.2 MPa f(εv)) (Jardine et al., 1986). Young’s modulus of other forma- Friction angle(1) [ϕ’] 30-38 ° tions (marine sands, marl and car- 0.6 + (100 m)/z-0.5 + (1500 m)/z Initial stress ratio [K] - bonates) were defined on the basis (z = depth in m) of data available in the literature (Fjær et al., 2008; Lancellotta, 2004) Coupling degree [A] NO; A = 2-10 - as well as the authors’ knowledge. (1) Values referred to reservoir only

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(lateral stress coefficient, K) (Brown & Hoek, 1978) and the interaction coefficient (A) between petrophysical properties and compressibility in coupled simulations. In particular the interaction coefficient (A) correlates permeability variations to porosity (and thus to volume) variations according to (Petunin et al., 2011): A k C S D T (4) k 00E U where k is permeability, ϕ is porosity and k0 e ϕ0 are the initial permeability and porosity, respectively. The exponent A can vary depending on the lithological and mechanical characteristics of the rock. In the case of sandstones A ranges between 2 and 10 (Santos et al., 2014). Once the range of the geological and mechanical parameters was de- Fig. 6. Schematic examples of the stratigraphy (not to scale) for different geological scenarios. R: reservoir; A: allochthon. fined, the simulations were perfor- Esempi schematici della stratigrafia (non in scala) per diversi scenari geologici. R: reservoir; med. A: alloctono. Moreover, in order to evaluate the impact of geological hetero- variation (three-dimensional effect (CPR) and it is expressed by the ra- geneity on subsidence, sensitivity of subsidence) which similarly are tio between maximum surface ver- analyses were performed to simu- maximum at the reservoir and redu- tical displacement and maximum late complex geological scenarios ce toward the surface (Figure 7). compaction of the reservoir, as first and/or characterized by significant Subsidence phenomenon calcu- investigated analytically in oedome- lithological/stratigraphic differen- lated through numerical models im- tric loading conditions by Geertsma ces. Some of the geological scena- posing triaxial loading conditions, (1973a, b): rios with different characteristics of was described by means of two sub- Maximumvertical the reservoir, caprock and overbur- sidence indices. The first index is displacementatthe surface den rocks are shown in Figure 6. In the Compaction Propagation Rate CPR = (5) particular a Young’s modulus equal Reservoircompacttion to 40 and 50 GPa was adopted for marly and carbonatic reservoirs, re- The second index is defined as spectively. Volume Loss Rate (VLR) and it is the ratio between volume variation caused by subsidence (i.e. volume 4.4. Subsidence indices of subsidence bowl) and the volume variation generated by compaction Downward vertical displacements of the hydrocarbon-bearing forma- induced by hydrocarbon production tion: are typically maximum at the top of Volumeloss at thesurface the reservoir (compaction pheno- VLR = (6) menon) and are gradually reduced Reservoir volumeloss towards the surface (subsidence phe- Fig. 7. Compaction and subsidence (adap- nomenon). Vertical displacements ted from Fjær et al., 2008). The reservoir volume loss was cal- (one-dimensional effect of subsi- Compattazione e subsidenza (modificata culated considering the rock portion dence) are associated with volume da Fjær et al., 2008). which undergoes pressure variation

90 Dicembre 2017 ambiente during production, that is, the gas- 4.5. Results Reservoir compaction propagates bearing interval and the aquifer con- to the surface and induces subsiden- nected to it, when present. Hydrocarbon production gene- ce, the intensity of which can be ac- If the effect of compaction does rates a variation of the stress condi- counted for by the two subsidence not propagate towards the surface, tions and thus deformations. indices described above. It should CPR and VLR will be zero. Conver- In Figure 8 and Figure 9 two be noted that the volume loss at the sely, when reservoir compaction pro- examples of the calculated compac- surface showing in VLR (eq. 6) was pagates entirely to the surface and tion and subsidence maps are given evaluated setting a threshold on the generates a subsidence of the same for a symmetric and an asymmetric minimum detectable vertical displa- entity, then CPR and VLR assume anticline respectively (reference cement. unit values; in some cases subsiden- data: d = 1500 m; Hres/Rres = 0.05; Even if different compaction 9 3 ce/compaction ratio as well as the V = 4.3 10 m sc; no aquifer; E’ = 1.7 and subsidence would be obtained ratio between the volume of the sub- GPa; ν’ = 0.3; c’ = 0.9 MPa; ϕ’ = 34°; if adopting the Modified Cam Clay sidence bowl and the reduction in K = 0.8; one-way coupling). model and/or a two-way coupled ap- reservoir volume may be even higher The results of the numerical runs proach, as verified with the additio- than 1. adopting the Mohr-Coulomb crite- nal simulated cases, the calculated Note that the indices only refer rion indicated that the behaviour of subsidence indices are representative to vertical displacements and do not the reservoir rock, in the range of to assess whether any critical situa- include horizontal displacements the investigated strength parame- tion might arise due to hydrocarbon and/or differential displacement. ters (c’ and ϕ’), is elastic. It should production from reservoirs. Therefo- The reason being that the indices be said that Young’s modulus has re the analysis of the variation range are meant to provide an indica- a significant impact on the extent of the two indices for the examined tion of the severity of subsidence. of the subsidence but not on the scenarios (Table 1) allowed the defi- Needless to say, should the indices evolution of the stress state, while nition of a qualitative reservoir clas- indicate that subsidence is signifi- strength parameters define failure sification, as reported in Table 2. cant, horizontal displacements and conditions but do not affect sub- Based on the indices analyses, re- differential displacements should sidence phenomena under elastic liable forecast of subsidence requires be evaluated to assess their poten- conditions. Finally, Poisson’s coef- detailed reservoir modelling as well tial impact on existing structures or ficient influences the evolution of as an accurate reconstruction of the infrastructures. both subsidence and stress induced structural and stratigraphic setting by production. of adjacent formations, especially

Fig. 8. Example of calculated compaction (a) and subsidence (b) maps for a symmetric anticline. Vertical displacements are normalized wrt the maximum reservoir compaction. Esempio di mappe di compattazione (a) e di subsidenza (b) ottenute dal calcolo numerico per un’anticlinale simmetrica. Gli spostamenti verticali sono normalizzati rispetto alla massima compattazione del giacimento.

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Fig. 9. Example of calculated compaction (a) and subsidence (b) maps for an asymmetric anticline. Vertical displacements are normalized wrt the maximum reservoir compaction. Esempio di mappe di compattazione (a) e di subsidenza (b) ottenute dal calcolo numerico per un’anticlinale asimmetrica. Gli spostamenti verticali sono normalizzati rispetto alla massima compattazione del giacimento.

Tab. 2. Reservoir classification based on subsidence indices. Classificazione dei giacimenti sulla base degli indici di subsidenza. Reservoir characteristics Subsidence index Subsidence – Deep reservoirs with small to medium size, without aquifers or with large aquifers CPR, VLR ≤ 0.25 Limited – Medium depth reservoirs with small to medium size, without aquifer – Deep reservoirs with small to medium size and with small to medium aquifers 0.25 < CPR, VLR < 0.8 Considerable – Deep reservoirs with medium to large size, without aquifers or with large aquifers – Shallow reservoirs – Medium depth reservoirs with small to medium size and with small to medium aquifer CPR, VLR ≥ 0.8 Significant – Medium depth reservoirs with large size, with or without aquifers – Deep reservoirs with medium to large size, with small to medium aquifers in the case of shallow hydrocarbon- petrophysical properties and pressu- For instance this could be the case bearing formations. re distributions within the reservoir, of asymmetric anticline reservoirs or The effects of heterogeneity can and contrast between stress-strain of more complex geological scena- be considered negligible or even properties (Suzuki et al., 2004; Fjær rios involving the presence of an al- null in particularly simple geologi- et al., 2008). lochthon wedge above the reservoir. cal scenarios, e.g. when the reser- When the geometry of the reser- Moreover, the presence of a more voir and the surrounding formations voir is very simple and symmetrical, rigid caprock than the reservoir atte- are laterally continuous and with a as is the case of the modelled anti- nuates the subsidence phenomenon; simple geometry, and/or when the cline analyzed and described above, conversely, the presence of a stiffer rock petrophysical and mechanical and the adjacent formations are ho- layer underlying the reservoir incre- characteristics as well as the pressure rizontal and have uniform thickness, ases subsidence (Geertsma, 1973b). distribution within the reservoir are the subsidence volume tends to a Reservoir classification based on rather homogeneous. On the con- regular bowl. When considering the values of the subsidence indices trary, the effects of heterogeneity more realistic and complex geologi- together with the degree of hetero- are not negligible in the case of re- cal scenarios, the distribution of ver- geneity led to the definition of the servoirs with irregular geometry, for- tical displacements on the surface Intact Rock Qualitative Subsiden- mations with significant thickness may be markedly heterogeneous and ce Index (IRQSI) which allows to changes, strongly heterogeneous thus produce irregular subsidence. qualitatively identify the degree of

92 Dicembre 2017 ambiente accuracy with which it would be Tab.3. Definition of the IRQSI based on subsidence indices and degree of heteroge- desirable to undertake subsidence neity. studies as well as assess underground Definizione dell’IRQSI sulla base degli indici di subsidenza e del grado di eterogeneità. safety conditions following the alte- Subsidence index Heterogeneity degree IRQSI Suggested approach ration of the initial stress state due to Prompt numerical or hydrocarbon production – or storage CPR, VLR ≤ 0.25 Negligible or nil 1 (Table 3 and Figure 10). analytical The definition of a prompt numerical model (IRQSI = 1) allows 0.25 < CPR, VLR < 0.8 From negligible to non-negligible 2 Simplified numerical a quick but approximate evaluation CPR, VLR < 0.25 Non negligible of the phenomenon to be analyzed. The geological characteristics of the CPR, VLR ≥ 0.8 From negligible to high reservoir and surrounding forma- 3 Complex numerical tions can be described in a simpli- CPR, VLR < 0.8 High fied way through regular geometries, sub-horizontal layering and discre- is small in relation to the radius and oil industry, allows to estimate the tization. The effect of production in the absence of an active aqui- extension (albeit in a conservative on pressure can be represented by fer, an analytic approach may be manner, particularly for scenarios an average depletion value for the used which, by nature, represents a which are far from the assumptions reservoir as well as in any hydrauli- prompt analysis. The analytical me- of Geertsma’s method) of subsidence cally connected aquifer. Alternati- thod proposed by Geertsma (1973a, induced by hydrocarbon production. vely, if the thickness of the reservoir 1973b), widely used throughout the The definition of a simplified -nu

Fig. 10. IRQSI-based subsidence study approach. Approccio allo studio della subsidenza suggerito sulla base dell’ISQRI.

Dicembre 2017 93 environment merical model (IRQSI = 2) makes three reference models: the geolo- In all cases, comparing the results it possible to refer to the average gical model at regional scale, which of numerical models with geodetic values of the necessary parameters allows to describe the stratigraphic- and/or satellite monitoring provide for the characterization of the un- structural features as well as the li- a way of evaluating the model ca- derground formations, even values thological/petrophysical properties pability to adequately reproduce the from the existing literature for simi- of the system under examination; mechanical behavior of the rocks lar formations can be used. Further the fluid-dynamic model, which in- as well as calibrating them through study to assess the impact of possible tegrates production history, PVT flu- back analysis processes. heterogeneities can include a sen- id parameters and rock-fluid interac- sitivity analyses on the mechanical tion parameters into the geological parameters. Particular attention model and is the basis for analyzing must, however, be given to viscous fluid-flow phenomena induced by References deformation (creep), which may oc- hydrocarbon production; the geome- cur in the absence of repressurization chanical model, which allows to stu- Baù, D., Ferronato, M., Gambolati, G., of the reservoir after production. dy stress-strain phenomena through Teatini, P., 2002. Basin-scale com- Conversely, the definition of a the geotechnical characterization of pressibility of the Northern Adriatic complex numerical model (IRQSI = all modelled formations and the se- by the radioactive marker techni- 3) requires the development of diffe- lection of a suitable constitutive mo- que. Géotechnique, vol. 52 (8), rent analysis scenarios (considering del describing rock and soil behavior pp. 605-616. doi: http://dx.doi. different production strategies, aqui- (Benetatos et al., 2010; Codegone et org/10.1680/geot.2002.52.8.605. fer sizes, constitutive models) and, al., 2016). Benetatos, C., Viberti, D., 2010. Fully above all, knowledge of deformation The analyses discussed in this pa- Integrated Hydrocarbon Reservoir and resistance parameters should be per are based on Mohr-Coulomb’s Studies: Myth or Reality?, American widened by integrating experimen- failure criterion which, albeit sim- Journal Of Applied Sciences, vol. 7 tal data, appropriately acquired by ple, is one of the most widely used (11), pp. 1477-1486. ISSN 1546- on-site and laboratory testing. models for studying intact rocks un- 9239. der monotonic loading conditions. Bertello, F., Fantoni, R., Franciosi, R., The use of complex constitutive 2008. Overview of the Italy’s Petro- models which account for the loa- leum Systems and Related Oil and 5. Conclusions ding history, non-linear behavior Gas Occurrences. CD Extended and/or time-dependent (viscous) Abstract & Exhibitor’s Catalogue, Geomechanical analyses show stress-strain behavior, is sometimes 70th EAGE Conference & Exhibi- how production induces stress varia- necessary but it must be adequately tion, A018, pp. 1-4. tions resulting in compaction of the supported by experimental analysis. Bertello, F., Fantoni, R., Franciosi, R., reservoir and surrounding aquifer It should be noted that the plan- Gatti, V., Ghielmi, M., Pugliese, A., when present. ning and interpretation of labora- 2010. From thrust-and-fold belt to Compaction of underground for- tory tests, which provide strength foreland: hydrocarbon occurrences in mations induces subsidence at the and deformation parameters, always Italy. In: Vining, B.A., Pickering, S.C. surface which needs proper eva- imply the assumption of a reference (Eds.) Petroleum geology: from ma- luation. The complexity of the ap- constitutive model. Moreover, the ture basin to new frontiers. Procee- proach to be used for quantifying mechanical response of geomate- dings of the 7th Petroleum Geo- vertical displacements and exten- rials to given stresses depends not logy Conference, pp. 113-112. doi: sion can be discerned based on the only on the type and magnitude of 10.1144/0070113. proposed Intact Rock Qualitative the applied stresses but also on the Brown, E.T., Hoek, E., 1978. Trends in Subsidence Index (IRQSI), which way in which they were applied Relationships between Measured In- relies on CPR, VLR and system he- (stress path). Similarly, fully cou- Situ Stresses and Depth. Internatio- terogeneity. The approach can go pled fluid-dynamic and geomecha- nal Journal of Rock Mechanics and from analytical, restricted to thin nical models are recommended in Mining Science & Geomechanics and homogeneous reservoirs subject particular situations such as highly Abstracts, vol. 15, pp. 211-215. doi: to a uniform depletion, to simplified compressible (i.e. shallow) and 10.1016/0148-9062(78)91227-5. or complex numerical modelling. fractured reservoirs and require the Brady, B.H.G., Brown, E.T., 2004. Rock In the case of numerical modelling, characterization of the interdepen- mechanics for underground mining, both fluid-dynamic and stress-strain dence between petrophysical pro- 3rd Edition. Kluwer Academic Pu- phenomena must be taken into ac- perties, mechanical properties and blishers, Dordrecht, 2004. count through the integration of stress state. Byerlee, J.D., 1978. Friction of Rocks.

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Pure and Applied Geophysics, 116 2010. A review of recent deve- Ghielmi, M., Minervini, M., Nini, C., Ro- (4-5), 615-626. lopments concerning the structure, gledi, S., Rossi, M., Vignolo, A., 2010. Carruba, S., Casnedi, R., Perotti, C.R., mechanics and fluid flow properties Sedimentary and tectonic evolution Tornaghi, M., Bolis, G., 2006. Tec- of fault zones. Journal of Structural in the eastern Po-Plain and northern tonic and sedimentary evolution Geology, vol. 32, pp. 1557-1575. Adriatic Sea area from Messinian of the Lower Pliocene Periadriatic Fischer, Q.J., Knipe, R.J., 2001. The per- B-537 to Middle Pleistocene (Italy). foredeep in Central Italy. Interna- meability of faults within siliclastic Rendiconti Lincei Scienze Fisiche tional Journal of Earth Sciences petroleum reservoirs of the North e Naturali, vol. 21, pp. S131-S166. (Geologische Rundschau), vol. 95, Sea and Norwegian continental doi: 10.1007/s12210-010-0101-5. pp. 665-683. doi: 10.1007/s00531- shelf. 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On 0960-3182. Rogledi, S., Rossi, M., 2013. Late the Generalized Stress-Strain Beha- Davis, G.H., Reynolds, S.J., Kluth, C., Miocene-Middle Pleistocene se- viour of “Wet” Clay. In Engineering 2012. Structural Geology of rocks quences in the Po Plain e Northern Plasticity Cambridge Univ. Press, and regions, 3rd edition. John Wiley Adriatic Sea (Italy): The stratigraphic Heyman and Leckie Ed., pp. 535- & Sons, Inc., New York, pp. 1-839. record of modification phases affec- 609. ISBN 978-0-471-15231-6. ting a complex foreland basin. Mari- Santos, E.S.R., Borba, A.M., Ferreira, Faulkner, D.R., Jackson, C.A.L., Lunn, ne and Petroleum Geology, vol. 42, F.H., 2014. Stress-Dependent Per- R.J., Schlische, R.W., Shipton, Z.K., pp. 50-81. doi: 10.1016/j.marpet- meability Measurement of Indiana Wibberley, C.A.J., Withjack, M.O., geo.2012.11.007. Limestone and Silurian Dolomite

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Samples in Hydrostatic Tests. ISRM Teatini, P., Castelletto, N., Ferronato, ry, Alberta, Canada, 1-3 Novem- Conference on Rock Mechanics M., Gambolati, G., Janna, C., Cai- ber 2005. for Natural Resources and Infra- ro, E., Marzorati, D., Colombo, D., Vezzani, L., Festa, A., Ghisetti, F., 2010. structure – SBMR 2014, 9-13 Sep- Ferretti, A., Bagliani, A., Bottazzi, F., Geology and Tectonic evolution of tember, Goiania, Brazil. 2011. Geomechanical response to the Central-Southern Apennines, Scholz, C.H., 1987. Wear and gouge seasonal gas storage in depleted re- Italy. Geological Society of Ame- formation in brittle faulting. Geo- servoirs: A case study in the Po River rica Special Paper, vol. 469, pp. logy, 15(6), 493-495. basin, Italy. Journal of Geophysical 1-58, accompanying by a CD- Suzuki, I., Morita, N., 2004. Subsidence Research, vol. 116(F2). ROM including the “Geological- and Horizontal Earth Surface Move- Tran, D., Nghiem, L., Buchanan, L., Structural Map of the Central- ment During Reservoir Depletion for 2005. An Overview of Iterative Cou- Southern Apennines (Italy)” at 3D Reservoirs With 3D Earth Sur- pling between Geomechanical De- 1:250,000 scale, Sheets 1 and 2. face. SPE Annual Technical Con- formation and Reservoir Flow. SPE doi: 10.1130/2010.2469. ference and Exhibition, Houston, International Thermal Operations http://unmig.sviluppoeconomico.gov. Texas, 26-29 September 2004. and Heavy Oil Symposium, Calga- it/ (accessed February 2016)

Acknowledgement This paper would not have been possible without the sponsorship of the Minis- try of Economic Development’s Directorate General for Safety – National Mining Office for Hydrocarbons and Georesources. In particular, authors would like to express their gratitude to the people who have supported this work along all the stages of its realization.

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P. Macini* Monitoring of drilling M. Ferrari* operations in the Italian G. Pisconti* * Università di Bologna, DICAM, offshore by means of virtual Dipartimento di Ingegneria Civile, Chimica, Ambientale e dei Materiali, “black boxes” Bologna

The study analyzes the systems for the monitoring of drilling activities in the Italian offshore, also in prevention, risk assessment and dedi- light of the requirements contained in the transposition of the Directive 2013/30/EU, enforced fol- cated emergency response plan in case lowing the Deepwater Horizon disaster in the Gulf of Mexico (2010). Today, the Italian law requires of major hazard. Among the others, Operators to set up an information technology system that guarantees the integrity, availability and we also recall that when granting li- non-repudiation of the technical parameters of drilling and drilling fluid, while respecting the principles censes, EU Countries must ensure of confidentiality and responsibility of the data, under all conditions. In Italy, Virtual “Black Boxes” have that companies are properly financed been implemented, i.e., data management systems coupled to the Mud Logging Units of offshore rigs, which allow the quasi-real time transmission of a subset of drilling parameters, and their integral and and have the necessary technical ex- safe storage on at least two separate servers hosted at the Operators’ facilities. These systems have pertise. Technical solutions, which been designed and built to ensure data safety and to prevent manipulation of the records. are critical for the safety of Operators’ Keywords: drilling, Oil&Gas production, drilling monitoring, offshore safety, data storage. installations, must be independently verified. This must be done prior to Monitoraggio delle attività di perforazione nell’offshore italiano tramite “black box” virtuali. Lo studio analizza i sistemi per il monitoraggio delle attività di perforazione nell’offshore the installation going into operation. italiano, alla luce dei requisiti contenuti nel recepimento della Direttiva 2013/30/UE, elaborata in National authorities must verify safety seguito al disastro dell’impianto offshore Deepwater Horizon (2010). La legislazione italiana obbliga provisions, environmental protection gli Operatori a predisporre un sistema di registrazione informatica che garantisca l’integrità, la dispo- measures, and the emergency prepa- nibilità e il non ripudio dei dati relativi ai parametri tecnici di perforazione e di controllo del fango del redness of drilling rigs and production pozzo, nel rispetto dei principi di riservatezza e responsabilità del dato, in ogni condizione. In Italia platforms. If companies do not respect sono state realizzate delle “Black Box” virtuali, sistemi informatici accoppiati alle unità di Mud Log- the minimum standards, EU countries ging dei cantieri di perforazione offshore, che consentono la trasmissione a terra in tempo quasi-reale can impose sanctions, including hal- di un sottoinsieme dei parametri di perforazione e la loro memorizzazione integrale e non manipo- labile su almeno due server distinti, ospitati presso le sedi operative degli Operatori. Tali sistemi sono ting production. Finally, information stati progettati e realizzati in modo da garantire la sicurezza e l’inalterabilità della registrazione. on how companies and EU countries Parole chiave: perforazione, petrolio e gas, monitoraggio perforazione, sicurezza offshore, archivio dati. keep installations safe must be made available for citizens (European Com- mission, 2017). 1. Introduction me the Directive 2013/30/EU of the European Parliament and of the Council Following the 2010 Deepwater of 12 June 2013 on safety of offshore oil Horizon disaster in the Gulf of Mexi- and gas operations and amending Direc- 2. Legislative Framework co, the European Commission (EC) tive 2004/35/EC (European Union, – Drilling Operations analyzed and revised the legislations 2013), hereinafter the “Offshore Di- Monitoring enforced in the European Union rective” (OD). (EU) and its Member States. In Oc- The OD establishes precise ru- In order to improve the monito- tober 2011, the EC proposed a draft of les for the entire cycle of offshore ring and safety of offshore drilling new rules on the safety of offshore oil Oil&Gas exploration, drilling and operations and, in case of a drilling and gas activities (Proposal for the reproduction. Under the control of the accident, to support the consequent gulation of the European Parliament and National Regulatory Authorities, inspection activity by the competent of the Council on safety of offshore oil European industry will have to pe- authorities of the Member States, the and gas prospection, exploration and pro- riodically evaluate and improve safe- OD reports that Member States shall duction activities, no longer in force). ty standards for offshore operations. ensure that, where appropriate, opera- The Regulation introduces clear rules This new approach will lead to a con- tors and owners take suitable measures for effective prevention and response tinually updated European risk asses- to use suitable technical means or proce- of a major accident. The Council of sment as it will take into account both dures in order to promote the reliability the EU, by means of its Working Party new technologies and knowledge and of the collection and recording of relevant on Energy, analyzed and revised the possible new risk scenarios. The OD data and to prevent possible manipula- above Proposal, which in 2013 beca- introduces requirements for effective tion thereof (Art. 19, Par. 10).

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 97-100 97 environment

The introduction of this para- Other examples of the official defi- 2015). In order to comply with the graph in the above-mentioned OD nition in the EU: A) Malta, Art. 40 of statutory obligations of the OD, the was proposed and strongly supported Subs. Legisl. 156.02-2015: Operators Operators of the Italian offshore de- by the Italian Ministry of Economic and owners shall take suitable measures vised recording systems that can be Development, which was actively to use suitable technical means or proce- better described as Virtual “Black involved in drafting the OD itself. In dures in order to promote the reliability Boxes” (VBB). It is not a real piece particular, it was accepted the Italian of the collection and recording of relevant of equipment installed at the rig site, proposal to include in the legislation data and to prevent possible manipula- but rather a system coupled with the the adoption of instruments such as tion thereof. B) UK, Sched. 2, Art. 3 Mud Logging Unit that transmits the the “Black Box”. It is worth mentio- of Statut. Instr. 2015 No. 398 Health drilling data recorded offshore to the ning that such a system was already and Safety…: The need to adopt suita- Operators’ headquarters facilities in enforced in the Italian legislation ble measures to use suitable technical me- quasi-real time. since 2011 (DGRME, 2011), long ans or procedures in order to promote the The Mud Logging Unit (MLU) is before the transposition of the OD in reliability of the collection and recording a vital part of any drilling rig, both Italy (Aug. 2015). of relevant data and to prevent possible onshore and offshore, and involves The 2011 Directorial Decree states manipulation of that data. C) Croatia, the monitoring and recording of a that the Operator provides an unalterable Art. 22, Act on the Safety of Offshore multiplicity of data related to the and secured, in every condition, compu- Expl.: The Competent Authority shall borehole and to the drilling process. terized recording system of drilling para- ensure that, where appropriate, opera- Mud logging integrates gas analysis meters and of drilling fluid parameters, to tors or owners take suitable measures and cuttings data with drilling infor- be made available to the body of supervi- under this Act to use suitable technical mation to build a continuous record, sors (Art. 28. Par. 10, letter e). This means or procedures in order to promote as the well is being drilled, known as text was modified in the Italian tran- the reliability of the collection and recor- “master log”. Equipment and services sposition of the OD (Gazzetta Ufficia- ding of relevant data and to prevent pos- for mud logging can range from sim- le, 2015), and it reads: “the Operator sible manipulation thereof. ple monitoring to integrated compu- shall provide appropriate procedures and / The aim of such a tool is to grant ter modeling of the wellsite and bo- or technical means to ensure reliable data the Body of Supervisors (in Italy, rehole environment. collection and data recording of drilling the territorial sections of the Natio- To guarantee the integrity, avai- and of safety of the operations and of the nal Mining Office for Hydrocarbons lability and non-repudiation of the installation, and to prevent manipulation. and Georesources – DGS-UNMIG data, the VBB is implemented by The Operator shall also prepare an infor- – of the Ministry of Economic Deve- deploying two dedicated and inde- mation technology system that ensures the lopment) a reliable access to drilling pendent servers: this duplication integrity, availability and non-repudiation data for the due analysis in case of is conceived for the redundancy of of the data, while respecting the principles accident, also in the light of taking the system, to increase its reliability. of confidentiality and responsibility of the the necessary legal action, and to ap- The servers capture data packets sent data, under all conditions, of the data re- ply the appropriate penalties. Last, from the offshore MLU at regular lating to the technical parameters of dril- but not least, the concept is that, in time intervals of 10 s (the sampling ling and drilling fluids, as well as other the event of offshore accidents, this rate of the offshore MLU is 5 s); the parameters…”. operational tool could help under- servers are located at the Operators’ Albeit the term “Black Box” is not standing the causes of the incident headquarters facilities. At present, explicitly indicated in the text of the and the circumstances that led to the data acquisition encompasses a num- OD, all EU Member States incor- failure of safety systems. ber of drilling parameters, mud sy- porated this concept into their own stem parameters and gas composition transposition of the Directive. In this (Tab. 1), complying with the techni- context, the “Black Box” (a term and cal specification accepted by DGS- a concept inspired by the flight recor- 3. Drilling Monitoring in UNMIG. ders installed on aircrafts) indicates the Italian Offshore; the Today, the mud logging Contrac- an information technology system Virtual “Black Box” tors operating in the Italian offsho- implemented to collect and record a re adopt different operative systems wide set of data concerning drilling In the last decade, the offshore for data acquisition, transmission operations. Drilling data are stored, drilling activity in the Italian off and storage, and so a single VBB protected and duplicated against any shore saw its historical minimum, hosted at the Operators’ headquar- possible amendment, and represent a and was performed exclusively by ters facilities, composed of two ser- sort of complete and reliable “histo- two Operators, Eni and Edison (25 vers, can manage only the data of a rical” record of the offshore drilling development wells and zero explo- single Contractor. In case of two or activity. ratory wells were drilled in 2013- more Contractors, the VBB must be

98 Dicembre 2017 ambiente duplicated, implementing the Con- Tab. 1. Set of recorded data, classified in macro-categories: Drilling parameters, Mud tractor’s specific operative system. system, and Gas composition. The operation of the VBB is accom- Set di dati registrati, distinti per macro-categorie: Parametri di perforazione, Sistema fango e plished by three different software. 1) Composizione del gas. Data acquisition, to receive the data Drilling Mud system Gas composition sets transmitted by the MLU and Depth bit (meas) – m Mud density in – kg/m3 Total gas – ppm which are stored in identical copies Depth bit (vert) – m Mud density out – kg/m3 Methane in the pair of VBB’s independent ser- Depth hole (meas) – m Mud flow in – l/min Ethane vers. 2) Visualization, similar to that Depth hole (vert) – m Mud flow out – % Propane of the MLU. 3) Internal monitoring Block position – m Pump stroke rate 1 – nr I Butane of the VBB system. Rate penetration – m/h Pump stroke rate 2 – nr N Butane In order to ensure the real-time alignment of the pair of the VBB Hook load (max) – ton Pump stroke rate 3 – nr I Pantane servers, these utilize a dual satellite Hook load (avg) – ton Pump stroke Count (cum) – nr N Pentane stream and disk mirroring, that ena- Weight on bit (max) – ton Stand pipe Pressure – kg/cm2 bles multiple digital content to be Weight on bit (avg) – ton Tank Volume (active) – m3 replicated several times, which can Rotary speed – rpm Trip Tank volume – m3 also be hosted in different countries. Bit revolution (down hole) – rpm Servers that host replicated content Rotary torque – kgm are the exact copy of a primary server on which the original versions of the cation of any malfunctioning. The the different servers (at the offshore files are loaded. Data acquired at the personnel with authorized access to drilling rig and at the onshore VBB), VBB are also transmitted to the Con- the computer room and responsible these are certified to ensure an up- tractor’s data-room through parallel for the VBB maintenance are organi- time of 99.5%. Transmitted data is satellite streams. Therefore, since zed in on-call duty. The VBB system either SSL or RSA (1024 bit) en- there are three different physical ser- administrators have a personal access cryption, and are stored on servers in vers that are completely independent username, under their responsibility. a read-only database. In the event of of one another (two in the VBB and VBB access usernames are tracked interruptions in the satellite connec- one in the Contractor’s data-room), and recorded at the Operator’s Com- tion, the data that are not transmit- there are also three different copies puter Security Office. On all servers ted would still be stored on board the of the recorded data sets for the be- installed at the VBB, a management system and then retransmitted once nefit of system redundancy. system is implemented to track all ac- the data link is restored. In this way, As for the technical means and/ tions completed by authorized users the VBB guarantees the complete- or procedures in order to promote to perform any information techno- ness of all the activities carried out and to prevent possible manipulation logy support activity. by the rig. Finally, a web-based en- and the reliability of the collection During the ordinary administration vironment is available to examine and recording of relevant data, the of the VBB system, it is not unlikely the VBB at the Operator’s computer VBB are designed in order to mini- the necessity of a joint software sup- room, as the server is password-pro- mize safety and security issues of the port together with personnel of the tected. For each mud logging Con- servers. Firstly, the physical access to mud logging Contractor. For this pur- tractor, a VBB system architecture the computer room is restricted to pose, a precise operational flow is pro- was designed and built according to authorized personnel only, each one vided: 1) The Operator reports to the the diagram shown in Figure 1. The with a certified personal badge. Each mud logging Contractor the presence MLU section is replicated as many single personnel access is recorded of a problem, or vice versa. 2) The times as the number of active rig for by the specific Integrated Security Operator sends to the mud logging each Contractor. System enforced at the Operator’s Contractor the token code to allow headquarters. Secondly, the power access to its network. 3)The Operator supply is guaranteed by a continuity sends to the mud logging Contractor system (electrical generator backed the password of access to the server. 4) 4. Discussion and up with batteries); a fire detection At the end of the operation, the sy- Conclusions and shutdown system is also present. stem password is changed and, upon Data backup of the servers, performed final checks, the nature of the opera- The study analyzed a system for every 10 minutes, is accomplished by tion is recorded in the logbook of the the monitoring of drilling activities an automatic system, together with a Operator’s Computer Security Office. in the Italian offshore, an informa- 24-7 maintenance service, equipped Concerning the satellite connection technology system that guaran- with a preset system of mail notifi- tions that allow dialogue between tees the integrity, availability and

Dicembre 2017 99 environment

Fig. 1. Architecture of the VBB system utilized in the Italian offshore. Architettura del sistema di “Black Box” virtuale (VBB) utilizzato nell’offshore italiano. non-repudiation of the technical the emergency preparedness of dril- that of the UNMIG, while on the parameters of drilling and drilling ling rigs and production platforms. other hand it is necessary to consi- fluid, while respecting the principles VBB have been implemented, i.e., der the size of the files to be display- of confidentiality and responsibili- data management systems coupled ed and studied, which would require ty of the data, under all conditions. to the MLU of offshore rigs, which considerable computational capabili- The set of drilling parameters re- allow the quasi-real time transmis- ties as well. A possibility might be to ported in Table 1 comply with the sion of a subset of drilling parameters, provide a stand-alone display system technical specification accepted by and their integral and safe storage on at UNMIG’s headquarters, similar to DGS-UNMIG. A careful evaluation at least two separate servers hosted that installed in the Operator’s VBB. of these parameters, also by means at the Operators’ headquarters faci- of numerical analysis, confirmed the lities. Today, data management and validity of this set of data to accom- visualization are guaranteed by speci- plish the requirements of the VBB fic software provided by mud logging References implemented so far, which is basical- Contractors and installed at the Ope- ly a post-analysis tool conceived for rators’ VBB servers. In the event that DGRME, 2011. http://unmig.mise.gov.it/ independent verifications by third UNMIG (the Body of Supervisors) unmig/norme/pdf/dd220311.pdf, last parties. The real-time monitoring requests access to VBB data, there are retrieved, 05 Sept. 2017. and analysis of the above set of data two scenarios: 1) UNMIG physically European Commission, 2017. http:// can help in further increasing the sa- moves one of the servers to conduct ec.europa.eu/energy/en/topics/oil-gas- fety of offshore drilling operations. In investigations at its headquarters; 2) and-coal/offshore-oil-and-gas-safety, fact, the VBB data allow, if correctly the Operator exports the required last retrieved, 05 Sept. 2017. and timely interpreted, to predicting data (e.g., csv files) and supplies them European Union, 2013. Official Journal of with a good level of confidence the to UNMIG. the European Union, 28.06.2013, http:// occurrence of potentially dangerous However, from the technical and eur-lex.europa.eu/legal-content/EN/ drilling conditions (e.g., overpressu- logistical standpoint there are some is- ALL/?uri = CELEX%3A32013L0030, red formations, early kick detection, sues, the overcoming of which would last retrieved, 05 Sept. 2017. circulation loss, etc.), that might be ensure better effectiveness of the VBB Gazzetta Ufficiale, 2015. Legislative De- favorable to the occurrence of major and greater readiness for action in the cree 145 of 18 August 2015, Imple- hazards on offshore facilities. Howe- case of critical events. In fact, on the mentation of Directive 2013/30/EU, ver, further investigations are in pro- one hand, there are obvious opera- http://unmig.mise.gov.it/unmig/norme/ gress in order to evaluate the oppor- tional difficulties in moving a server pdf/gu160915.pdf, last retrieved, 05 tunity to implement in the present from the Operator’s headquarters to Sept. 2017. VBB additional parameters recorded while drilling, such as logging, direc- Acknowledgement tional, geosteering, instrumented bits data, etc., in the light of proposing The study was carried out in the framework of the Research Project “Network for to Safety Authorities more reliable Offshore Safety”, funded by the Italian Ministry of Economic Development, Directo- tools to verify safety provisions, envi- rate-General for Safety of Mining and Energy activities, National Mining Office for ronmental protection measures, and Hydrocarbons and Georesources (DGS-UNMIG).

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S. Grandi* Planning for a safe and D. Airoldi** I. Antoncecchi*** sustainable decommissioning S. Camporeale*** of offshore hydrocarbon A. Danelli** W. Da Riz**** platforms: complexity and M. de Nigris** P. Girardi** decision support systems. V. Martinotti** Preliminary considerations N. Santocchi* * Ministry of Economic Development, Division 6 of the Directorate General for Safety of Mining and Energy Activities – National Mining Office for Hydrocarbons A national decommissioning programme of offshore hydrocarbon platforms, regardless of the total and Georesources (DGS-UNMIG) or partial removal hypothesis for further alternative uses, should be based on sustainability and safe- ** RSE S.p.A., Milano ty principles. In order to carry out this sensitive and complex activity, it is necessary that the com- *** University of Milan, “Bicocca” on petent authorities and operators have, in addition to a relevant regulatory framework, criteria and secondment to DGS-UNMIG, Milano methodologies that make the assessment of technological options from a safety, social, economic **** GSE S.p.A. and environmental viewpoints possible. This paper presents a first overview of the study performed on decision support system methodologies with focus on Multi-Criteria Analysis (MCA), carried out within the framework of the “Safe and Sustainable Decommissioning (SSD)” project whose goal is to develop a decommissioning program based on the definition of indicators and of objective criteria well as social inter- and intra-gene- for removing or converting offshore hydrocarbon platforms. rational equity, in one word it has to Keywords: offshore platforms, Oil&Gas, Multi-Criteria Analysis, Decommissioning, Adriatic Sea. be “sustainable”. Pianificare in modo sostenibile e in sicurezza la dismissione delle piattaforme di In Italy, as well as in other parts idrocarburi offshore: complessità e sistemi di supporto di alle decisioni. Considera- of the world (such as the USA, the zioni preliminari. I programmi a scala nazionale per la dismissione delle piattaforme di idro- North Sea, etc.), the vast majori- carburi offshore, indipendentemente dall’ipotesi di rimozione totale o parziale o per ulteriori usi ty of the offshore Oil&Gas instal- alternativi, devono essere basati sui principi di sostenibilità e sicurezza degli impianti e dei lavoratori. lations (mainly jacket steel plat- Per poter svolgere questa delicata e complessa attività, è necessario che le autorità competenti e gli forms) were developed during the operatori dispongano, oltre che di un quadro normativo di riferimento, anche di criteri e metodologie 1960s and 1980s. In particular, 49 sostenibili e sicure che consentano la valutazione delle possibili opzioni tecnologiche. Questo lavoro platforms, positioned in very shal- presenta una prima panoramica dello studio condotto sulle metodologie di supporto decisionale low waters, have already reached con particolare riferimento all’Analisi Multi-Criteri (AMC). Lo studio si svolge nell’ambito del progetto the end of their economic life and “Safe and Sustainable Decommissioning (SSD)”, il cui obiettivo è quello di sviluppare un programma decommissioned (Assomineraria, di dismissione degli impianti offshore basato sulla definizione di indicatori e criteri oggettivi per la rimozione o la conversione ad altro utilizzo delle piattaforme offshore. 2016) (see Table 1) whilst about Parole chiave: piattaforme offshore, Oil&Gas, analisi multi-criteri, dismissione mineraria, Mar 145 offshore Oil&Gas platforms Adriatico. are still in operation offshore in the Italian coast within and outside the 12-mile zone. It has to be noted that in the 1. Introduction advanced planning (planning ahead former decommissioning campai- at least 2 years before production en- gns all the topsides, treatment fa- The perception of decommis- ded), engineered solutions, research cilities, deck infrastructures were sioning of offshore facilities in the and development, reuse and the dismantled and conveyed in de- Oil&Gas industry and public opi- discussion on sustainable disposal dicated onshore areas for the final nion has changed over the years. (Twachtman, 1997). Decommissio- recovery and disposal whilst 23 ja- Indeed growing attention in projec- ning is an important phase of the cket steel infrastructures were used ting, environmental impact asses- life-cycle of offshore Oil&Gas plat- as an artificial reef in a pre-selected sment and in public awareness has forms and should be based on prin- dedicated area in the Adriatic Sea, been observed in the past decades. ciples of: safety, economic efficiency, approximately 12 nautical miles In the 1990s, the main trends were: preserving ecological integrity as offshore the coastline, named «Pa-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 101-108 101 environment

Tab. 1. List of decommissioned offshore platforms in Italy (years 1966-2016) (source: Assomineraria, 2016). Lista delle piattaforme già dismesse minerariamente in Italia (anni 1966-2016) (fonte: Assomineraria, 2016). Platform Installation (year) Sea depth (m) Well (n.) Decommission (year) Destination Porto Corsini 6 1965 24 1 1966 T Porto Corsini 9 1965 24 1 1967 T Porto Corsini 1 1966 23 1 1968 T Cervia mare 3: 1966 22 1 1985 T Porto Corsini b alloggi 1968 25 1986 T Porto Corsini 3 1963 21 1 1989 T Nilde (FPSO) 1982 100 2 1989 T Porto Corsini 4 1964 22 1 1990 P Porto Corsini 7b 1965 25 1 1990 P Porto Corsini 10 1966 25 1 1990 P Porto Corsini 11 1966 25 1 1990 P Porto Corsini 12 1966 25 1 1990 P Porto Corsini 7 1966 25 1 1990 P Porto Corsini 8 1966 24 1 1990 P Cesenatico mare 1 1961 9 1 1991 P Ravenna mare 5 1962 10 1 1991 P Ravenna mare 6bis 1961 10 1 1991 P Cesenatico mare 3 1965 10 1 1991 P Cesenatico mare 4 1965 3 1 1991 P Punta Marina 3 1966 9 1 1991 P Porto Garibaldi mare 1 1968 25 1 1991 P Punta Marina 2 1965 9 1 1992 P Ravenna mare a alloggi 1967 10 1995 T Ravenna mare a 1968 10 10 1995 T Porto Corsini w prod 1968 12 8 1995 T Porto Corsini wa alloggi 1968 12 1995 T Porto Corsini wb alloggi 1968 13 1995 T Porto Corsini 25 1976 23 1 1996 T Porto Corsini 25bis 1976 23 1 1996 T Narciso 2 1985 21 1 1997 T Lavinia 1981 90 1 1997 T Ravenna mare sud 1 1961 9 1 1999 P Porto corsini a 1967 25 4 1999 P Porto corsini 1bis 1968 25 8 1999 P Ravenna mare sud 5 1968 9 1 1999 P Porto Corsini b 1968 25 8 1999 P Ravenna mare 4 1960 10 1 2000 T Ravenna mare 7 1963 12 1 2000 P Anemone 2 1973 22 1 2000 T Porto Corsini 26 1978 25 1 2000 P Porto Corsini 27 1979 24 1 2000 P Porto Corsini 30 1982 24 1 2000 P Cervia 25 1986 27 1 2000 P Flavia 1981 10 1 2001 T Fulvia 1981 12 1 2001 T Mila 5 1980 52 1 2003 T Mila 4 1985 45 1 2003 T Mila 6 1985 45 1 2003 T Mormora mare 1-4 1985 15 2 2005 T San Giorgio mare 4 1973 18 1 2005 T T = transport to shore; P = reuse as artificial reef.

102 Dicembre 2017 ambiente guro» (now a Site of Community Tab. 2. International and regional regulatory framework for the decommissioning of Importance – SCI). The remaining offshore platforms. 26 decommissioned platforms were Quadro regolatorio internazionale e regionale per la dismissione mineraria delle piattafor- removed and treated in dedicated me offshore. onshore areas for final disposal (As- Convention/Guideline Objective Date Internal reference somineraria, 2016). Geneva Convention on the Continental Shelf 1958 Art 5 1 and 5 5 In Italy, according to DGS- UNMIG studies (Grandi, 2017; Barcelona The Convention for Protedjon of the 1976 Art. 20 Caliri et al., 2017; Antoncecchi et Mediterranean Sea against Pollution al.,2017) at least 20 offshore plat- UNCLOS United Nations Convention on the Law 1982 Art. 60.3 forms (mainly extracting natural of the Sea gas and located in shallow waters) will come to the end of their useful IMO Guidelines and Standards for the 1989 Art. 3.1 and 3.2 production lifetime between 2017 (International Maritime removal of offshore installations and and 2021 and more are expected to Organization) structures on the continental shelf and in be decommissioned by 2030 and la- the exclusive economic zone ter. OSPAR Convention for the Protection of the 1992 Decision 98/3 Over the last decades, internatio- Marine Environment of the North-East nal and national regulatory, techno- Atlantic logical and ideological frameworks have changed significantly, therefore and with the Ministry of Cultural economic and environmental a need for refreshing the decommis- Heritage, will adopt national guide- viewpoints possible. sioning approach is of the essence. lines for the decommissioning of the These points are also relevant In particular, current international offshore platforms in order to ensure considering that as alternative to to- and regional regulatory frameworks the quality and completeness of the tal removal, there are other decom- (i.e. the Geneva Convention 1958; assessment of their environmental missioning options (see Figure 1), the Barcelona Convention 1976, the impact. each one characterized by its own UNCLOS Convention 1982, the This provision also aims at tac- impact on the environment, costs, IMO Guidelines 1989, the OSPAR kling the issue that a significant socio-economic and security aspects; Convention 1992) are in favour of a number of the platforms entering in i.e. bearing in mind the growing sen- complete removal at the end of the the decommissioning phase did not sitivity to aspects of sustainability useful life of offshore Oil&Gas plat- undergo an Environmental Impact (economic, environmental and so- forms, pipelines and other ancillary Assessment (EIA) procedure becau- cial) and safety in the broader sen- offshore infrastructure provided that se it was not applicable at the time. se. In addition, the application of maritime shipping, fishing and envi- On the basis of the current Ita- the principles of the so-called Blue ronmental protection are taken into lian legislation, decommissioning Economy (European Commission, account (see Table 2). projects, regardless of the total or 2017) should be considered as well. With reference to the Italian law, partial removal hypothesis for fur- In order to choose the best de- it should be noted that although ther alternative uses, must certainly commissioning option from sustai- there is currently no systematic and take place in total safety, must re- nability and safety standpoints, homogeneous regulatory framework spect the environment (the marine appropriate decision-making to- for decommissioning Oil&Gas ex- ecosystem), maritime navigation, ols should be available to allow an traction plants, the most recent not forgetting social impact (labour objective, traceable and transparent indications are in the Legislative for instance) and financial duties on assessment of the various possibili- Decree no. 145 of 18 August 2015, companies. ties. In particular, this paper aims which transposes European Directi- The results of the above mentio- at presenting a first overview of the ve 2013/30/EU (“Offshore Directi- ned elements highlight that to carry study performed on decision support ve”), article 2, paragraph 1, point gg, out this sensitive and complex acti- system methodologies with focus as well as article 25, paragraph 6 of vity in the years to come, it is neces- on Multi-Criteria Analysis (MCA) the Legislative Decree no. 104 of 16 sary that the competent authorities that can back up decision making June 2017 (“Environmental Impact and operators have: among all possible options to be fol- Assessment”), which says that the 1. a relevant regulatory framework, lowed in the decommissioning phase Ministry of Economic Development, 2. criteria and methodologies that developed within the “Safe and Su- in agreement with the Ministry for make the assessment of techno- stainable Decommissioning (SSD)” the Environment, Territory and Sea logical options from safety, social, project (see Figure 2).

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proach. Among these we adopt the methodological framework proposed by Keeney and Raiffa (1993). The method consists of 4 main phases: – identification or generation of a set design of alternatives and options; – assessment of the identified options and impacts over time, through a series of measurable criteria to assess the extent to which the decision making group objectives have been achieved; the result is a performance matrix Fig. 1. Decommissioning options. in which each row describes an Opzioni di dismissione mineraria. option and each column describes the performance of the options against each criterion; – normalization of criteria, by means of utility functions that express the satisfaction of the decision maker on the basis of a single criterion and translate them into a unique unit of measurement; – weight assignment, expression of the relative importance of each criterion. Because the decommissioning of offshore platforms involves high costs and a series of potential environmental impacts, the choice about what is more suitable to do when platforms reach the end of their useful oil and gas production, can become an issue of public controversy. In this framework, we are outlining a method of MCA for evaluating and Fig. 2. The “Safe and Sustainable Decommissioning (SSD)” project. comparing alternative decommissio- Il progetto “Safe and Sustainable Decommissioning (SSD)”. ning options across key selection criteria, including environmental, eco- 2. The Multi-Criteria dologies as a decision support tool is nomic, societal, technical feasibility Analysis approach due to the failure of classical econo- and safety considerations. mic/monetary analysis in handling multidisciplinary aspects required in Multi-Criteria Analysis (MCA) the comparison of different design can be helpful to solve a decision pro- and planning alternatives. It is im- 3. The Multi-Criteria blem whenever multiple conflicting portant to shed light on the fact that Approach to Oil&Gas objectives are present. In general, MCA techniques do not define the platform Decommissioning every decision choice or process, ta- optimum solution among a set of al- ken by either a single decision-maker ternatives, but can be used to identify or a stakeholder group, involves en- a single most preferred option or to As aforementioned, the MCA of- vironmental, social and economic ef- rank options with a transparent, ex- fers a well-structured and objective fects that need to be assessed. In parti- plicit and reproducible process. There framework for evaluating and com- cular, the more and more importance are several different methodologies paring the performance of multiple gained by the Multi-Criteria metho- that are part of the MCA general ap- options across numerous selection

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Fig. 3. Different decommissioning options: (a) leaving the rig unaltered in its current location; (b) toppling the entire structure in its current location; (c) partially dismantling the rig through “topping” – the removal of only the upper portion of the rig; (d) transport the rig to shore (Macreadie et al., 2011). Opzioni di dismissione: (a) “abbandono” della piattaforma nella sua posizione attuale; (b) ribaltamento in loco dell’intera struttura, “toppling”; (c) taglio della porzione superiore della piattaforma, ed abbandono in situ; (d) trasporto della piattaforma a terra (Macreadie et al., 2011). criteria (Fowler et al., 2014). The the platform in place intact, with a instance, Bernstein et al. (2010) de- proposed method follows a well-defi- conversion to a reef or with a reuse scribed a method to quantitatively ned process that in general includes: for other purposes, to the complete estimate the criterion “production 1) definition of the decision objec- removal (see Figure 3). of exploitable biomass” for different tives to achieve and set up the In this regard, it should be no- decommissioning options. The total selection criteria that reflect the ted that in Italy, current legislation biomass B populating a platform can objectives; excludes the possibility of leaving be estimated by the sum of the fol- 2) identification of the decommis- the rig unaltered in its current loca- lowing terms: sioning options suitable for the tion. The elaboration of an alterna- 1) bottom biomass Bb, defined as the rig (or a group of platforms) under tives list to consider in the analysis fish biomass in the lowest 2 m of a consideration; should take into account site-specific platform; 3) performance evaluation of each conditions: distance of the platforms 2) middle Bm, biomass from 2 m off disposal alternative for each crite- from shore, water depth, local sta- the bottom to the partial removal rion; keholder interest for the reuse of the depth; 4) assigning a weight to each crite- oil rig and regulatory restrictions. 3) upper Bu, fish biomass populating rion according to their level of The following step after the decision the part of the platform that will importance; criteria and decommissioning op- be removed in case of partial di- 5) combination of the criteria eva- tions selection is the construction of smantling through “toppling”. luation and weights into an ove- a performance matrix in which each This means that the total biomass rall performance estimate for each row describes a decommissioning al- B is equal to Bb + Bm + Bu. The “com- decommissioning option; ternative and each column describes plete removal” decommissioning op- 6) selection of the best disposal al- the performance of the alternative tion entails the entire loss of biomass ternative based on overall perfor- against each criterion (see Table 3). B, while for the “partial removal” mance. The performance assessment can be option with upper jacket relocated Perhaps an example can shed both quantitative (cardinal num- to shore, the adjusted biomass will some light on the method propo- ber) and qualitative (dimensionless be: Badj = Bb + Bm. In case the upper sed. Criteria – e.g. decommissio- ranking). It is not easy to find quan- jacket is disposed of on sea floor as ning costs, impact on water and air titative indicators influenced by the a reef, under the hypothesis that the quality, impact on fish production, different options, but when feasible new habitat will have a similar fish technical feasibility – represent the to use them it is preferable. community to the nearby platform, objectives to be maximized (or mi- The scientific literature in this the biomass is calculated adding an nimized) by the decision makers and area offers different examples of cri- adjusted (i) bottom and midwater by all stakeholders involved in the teria quantitative assessment. For value scaled to the size of the jacket decision, reason for which the criteria list should be refined in consul- Tab. 3. Example of performance matrix. tation with all of them. Generally, Esempio di matrice di performance. every stakeholder chooses their own criteria set to better represent their Costs (€) Fish production (kg) Greenhouse gas emissions (kg CO2) own interests, according to specific Complete removal I11 I12 I13 situation requirements. The disposal options can range from leaving Rig to Reef I21 I22 I23

Dicembre 2017 105 environment placed on the bottom, according to certain degree of interaction betwe- is an expert of water quality could the formula: B = Bb + Bm + Bbi + Bmi. en the technician and the stakehol- suggest the values of the coefficients To compare these various asses- der. A way to simplify this process is for organic pollution and non-or- sments, it is necessary to proceed organizing criteria and indicators in a ganic pollution, that belongs to the with a normalization process (see so called decision tree (Figure 4). “Water” criterion, leaving the politi- Table 4). In this way it is possible to assign cian with the task of defining the co- This process converts the crite- the coefficients for every group of efficients for the economic and the ria assessments into dimensionless nodes that are children of the same environmental sectors). values, making them comparable to node, for every level of the tree. Insi- Vcomplete removal = w 1U11 + w2U21 + each other. This transformation is de each group, the sum of the coeffi- + w U (1) done by means of utility functions cients must be equal to 1. 3 31 (a different one for each criterion), This process is called hierarchic Vrig to reef = w 1U13 + w2U22 + that assign each value of the criteria allocation of the weights and an + w U (2) assessments a corresponding dimen- example is shown in Figure 4. The 3 32 sionless preference score, ranging weights associated to each leaf of the Given the controversial nature of between a minimum value (normal- hierarchy are calculated as product decommissioning decisions, partici- ly 0) and a maximum value (1, 10 of the coefficients assigned from the pation to the MCA process of both or 100) (Dodgson et al., 2009). The leaf to the root of the tree. technical experts and stakeholder general formula for the utility fun- For example, referring to Figure 4 groups is highly recommended. ctions is Ui = f(Ii) for the indicator Ii. the weights of SO2 criterion is given Generally, the decision criteria by the product of the coefficients are characterized by different levels assigned to SO2 itself, air and envi- of importance that would be appro- ronment. 5. Forward research: priate to include in the overall eva- Lastly, it is possible to calculate options and criteria luation. Therefore, a “weight” is assi- the overall performance V of each selection with the gned to each criterion that expresses decommissioning alternative, using stakeholder involvement its relative importance in relation to the formulas reported below (1) the other criteria considered. The (2), and make a comparison among weights assignment to the criteria them: the option with highest per- As discussed above, an important reflects the preference structure of formance value will be the best one step of the methodology is the selec- the decision maker, in this sense the according to the proposed MCA me- tion of the evaluation criteria and choice is completely subjective. The thod. their organization in a decisional MCA process allows managing this This kind of allocation has the tree. Although this step should in- subjectivity in a transparent way. advantage that coefficients are assi- volve decision makers and relevant Commonly, the sum of the weights is gned to homogeneous elements and stakeholders, it is worth starting equal to 1, and their value is alloca- so it is possible for different groups of with a literature-derived decision ted by the decision makers involving experts to work on the definition of tree. The criteria selection is based the stakeholders. coefficients linked to their own ex- on past studies related to MCA ap- The vector of weights should be pertise. plication to the decommissioning stated by the stakeholder, because it In general, coefficient allocation of Oil&Gas platforms. In particu- should be representative of his/her on the leaf can be done by experts lar, the following papers have been structure of preferences. This is not of the sectors involved. While going analyzed in detail: always simple or immediate, because back up in the hierarchy, it is neces- – A Multi-criteria decision approach the rigorous procedure to obtain the sary that politicians suggest the va- to decommissioning of off-shore oil vector of the preferences requires a lues to adopt (e.g. a technician who and gas infrastructure (Fowler et al., 2014). Tab. 4. Normalization process by means of utility functions. The article underlines that, al- Processo di normalizzazione tramite le funzioni utilità. though the complete removal is considered the most environmen- Costs (-) Fish production (-) Greenhouse gas emissions (-) tally-sound option, there are Complete removal U U U examples in the world where oil 11 12 13 structures are now habitats to di- Rig to Reef U U U verse marine communities. For all 21 22 23 these reasons a case-by-case ap- Weight w1 w2 w3 proach to decommissioning is re-

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pacts, ocean access impacts, compliance. The final list of criteria takes into account the results from the literary review, Italy’s specific conditions as well as the availability and reliability of data for indicator quantification. The 26 evaluation criteria are grouped into 4 major categories: Environmen- tal, Economic, Societal and Technical and they are shown in Figure 5. Of course, the criteria list and the decommissioning alternatives should be refined with the support of key stakeholders and experts, to be engaged in specific round tables, bearing in mind that the success of the proposed methodology is based on a wide and active participation of all Fig. 4. Example of weights assignment following the decision tree hierarchy. stakeholders. Esempio di assegnazione dei pesi seguendo la gerarchia dell’albero delle decisioni.

quired. In this study, the authors assessed are the partial jacket remo- proposed a generic list of criteria val and the complete jacket removal. 6. From studies to applicable to most offshore de- The criteria are 12 and they are structured planning commissioning decisions. The grouped into safety, environment, criteria are 39 and are grouped technical, societal and economic. Current Italian and international into 5 major categories (envi- – A multi-attribute decision analysis regulatory frameworks favour com- ronmental, financial, socioecono- for decommissioning off-shore oil plete removal at the end of the life mic, health and safety, additional and gas platforms (Henrion et al., cycle of offshore Oil&Gas platforms, stakeholder considerations) to 2015). sealines and other ancillary offshore help comprehension of the deci- In the near future, California will infrastructures. However, social, en- sion-making problem. face decommissioning of 27 oil vironmental and economic benefits – Using Comparative Assessment and gas platforms located offsho- of total removal policy may not be Methods to Determine Preferred re to the South of the region. For always warranted because other op- Options in Pipeline and Jacket De- this reason the State of California tions (such as leave in place, partial commissioning (Ferris and Tjea, requested the California Ocean removal, reuse for other purposes or 2015). Science Trust (an independent nearby relocation) may be a better This study proposed a compara- non-profit organization) a com- choice. tive assessment method to eva- prehensive policy analysis to bet- The adoption of these alternative luate decommissioning options. ter understand the decommissio- solutions is stimulating a lively de- The comparative assessment was ning issue. The definition of the bate among stakeholders in order to applied for the decommissioning attributes on which the analysis is tackle challenges and opportunities of the Murchison platform in the based required a big effort. First, in the short and longer terms. Northern North Sea (156 m wa- an initial list was created from a To reinforce the MCA model, a ter depth). Murchison was one of literature review and the history consultative approach has been star- the biggest platform in the North of this topic. Then the list was re- ted in order to further collect possible Sea, with its jacket weighing in fined according to the results of a scenarios, information about public total more than 26000 tonnes. working group of experts. In the opinion perceptions, tests and vali- For this reason it was necessary to end the objectives were organized date indicators and criteria. In parti- evaluate a possible derogation to in the following 8 attributes (cri- cular, some sessions have been carried the Convention For The protec- teria): economic costs, air quality, out via the “Forum of the Future of tion of The Marine Environment water quality, impact on marine Offshore Platforms” launched at the Of The North-East Atlantic mammals and birds, marine re- Offshore Mediterranean Conference (OSPAR 98/3). The two options sources fish biomass, benthic im- & Exhibition (OMC 2017). Coupling

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References Fowler, A.M., Macreadie, P.I., Jones, D.O.B. and Booth, D.J., 2014. A Antoncecchi, I., Camporeale, S., Da Riz, multi-criteria decision approach to W., Grandi, S., Martinotti, V., San- Decommissioning of offshore oil and tocchi, N., 2017. Productive state gas infrastructure. Ocean&Coastal of the Oil&Gas platforms: a clas- Management, Volume 87, pp. 20- sification proposal for the mining 29. statistical review. Geoingegneria Grandi, S., 2017. The future of the Ambientale e Mineraria (in press). platforms and the Blue Economy: Assomineraria, 2016. Guida tecnica Decommissioning, Multipurpose operativa per lo smantellamento a or other Uses?. Presented to: Of- fine vita degli impianti, installazioni, fshore Mediterranean Conferen- infrastrutture e piattaforme utilizza- ce & Exhibition OMC 2017, 29- ti per la coltivazione di idrocarburi in 31 March, Ravenna (Italy). http:// mare e il ripristino dei luoghi. Rap- unmig.mise.gov.it/unmig/info/ porto interno, pp. 1-41. omc2017/presentazioni/decom- Bernstein, B.B., Bressler, A., Cantle, P., missioning/grandi.pdf Fig. 5. Decision tree with the selected objec- Henrion, M., DeWitt, J., Kruse, S., Ferries, J.,Tjea, J., 2015. Using Cim- tives and criteria. Pondella, D., Scholz, A., Setnicka, parative Assessment Methods to Albero decisionale in cui si riportano gli T., Swamy, S., Fink, L. and McCann, Determine Preferred Options in obiettivi ed i criteri selezionati. B., 2010. Evaluating Alternatives Pipeline and Jacket Decommissio- for Decommissioning California’s ning. Presented to: Indo Decomm MCA and consultation processes can Offshore Oil and Gas Platforms: A in Oil&Gas 2015, 13-14 August, be said to be a methodological inno- Technical Analysis to Inform State Bandung (Indonesia). vation, at least in this sector. Howe- Policy. California Ocean Science Henrion, M., Bernstein, B. and Swamy, ver, further studies and development Trust. S., 2015. A Multi-Attribute Decision of SSD project steps are needed. Caliri, A., Carbone, S., Cianella, R., Analysis for Decommissioning Of- In all cases, it seems that key to a Grandi, S., 2017. The Italian expe- fshore Oil and Gas Platforms. Integr. sustainable choice between the va- rience and state of the art. 14th Environ. Assess. Manag., Volume rious decommissioning options is to EUOAG Meeting – Workshop on 11, pp. 594-609. ensure availability of information Decommissioning of offshore in- Keeney, R.L. and Raiffa, H., 1993. De- along with the right decision-making stallations: Challenges, options and cisions with multiple objectives- tools. Thus, the “Safe and Sustaina- lessons learned. Brussels, 20th Sep- preferences and value tradeoffs, ble Decommissioning” project could tember 2017. Cambridge University Press, Cam- be an important base to develop su- Dodgson, J.S., Spackman, M., Pearman, bridge & New York. itable decommissioning programs A. and Phillips, L.D., 2009. Multi- Macreadie, P.I., Fowler, A.M. and Bo- that will assist regulators, operators criteria analysis: a manual, Commu- oth, D.J., 2011. Rigs-to-reefs: will and stakeholders in ensuring awa- nities and Local Government Publi- the deep sea benefit from artificial reness, best available technologies, cations, West Yorkshire. habitat?. Frontiers in Ecology and defining indicators, objective criteria European Commission, 2017. Com- the Environment, Volume 9(8), pp. and implementing shared decommission staff working document, Re- 455-461. missioning programs for offshore port on the Blue Growth Strategy To- Twachtman, R., 1997. Offshore-plat- platforms and their infrastructures in wards more sustainable growth and form Decommissioning perceptions Italy. In particular, the development jobs in the blue economy. Brussels, change. Oil&Gas Journal, Volume of the MCA tool is going to be an ad- SWD(2017) 128 final, pp. 1-61. 95(49). ded value policy instrument in line with other approaches found in the literature for California (Bernstein et al., 2010; Henrion et al., 2015) to decide whether removing or converting Acknowledgement offshore hydrocarbon platforms. This work is the result of a collaboration among Research Centres and Uni- The MCA can be helpful to as- versities (CRIET – University of Milan, Bicocca and the RSE S.p.A) within the sist problem analysis and decision project called “Safe and Sustainable Decommissioning” a part of the programme processes, especially when multiple called “Network of the Offshore Safety” funded by the DGS-UNMIG, Ministry of conflicting objectives are present. Economic Development.

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I. Antoncecchi* Productive state of the S. Camporeale* W. Da Riz** Oil&Gas platforms: S. Grandi*** a classification proposal for V. Martinotti**** N. Santocchi*** the mining statistical review * University of Milan, “Bicocca” on secondment to DGS-UNMIG ** GSE S.p.A. Over the last years in Italy, as well as in the rest of the world, the debate about the state of the *** Ministry of Economic Development DGS-UNMIG Div. VI Oil&Gas production platforms has caught more and more the attention of the media. This activity **** Ricerca sul Sistema Energetico – presents critical issues at social, environmental and economical levels for defining plans of mining RSE S.p.A. closure and infrastructure decommissioning most of all. Establishing a scientific method to classify mining platforms and wells, and identifying an objective and systematic terminology, on the basis of their utility to reservoir production is becoming essential as well. The scientific literature uses a terminology for oil and gas wells, but on the contrary no international standard and common criteria are used for productive platforms. This paper aims at the proposal of a terminology and a classifica- This issue led the Italian Mini- tion method that could be adopted by the Italian Authorities for the analysis of the state of offshore stry of Economic Development to Oil&Gas platforms, through the evaluation of the national database of the Italian Ministry of Eco- verify the nature of existing oil and nomic Development – Directorate General for safety of Mining and Energy Activity (DGS-UNMIG). gas platforms. This paper proposes a Keywords: classification, Oil&Gas, platforms, terminology, decommissioning. terminology and a classification me- Stato produttivo delle piattaforme Oil&Gas: una proposta di classificazione per la thod, which could be adopted by the statistica mineraria. In questi anni in Italia, così come nel resto del mondo, il dibattito sullo stato Italian Authorities for the analysis produttivo delle piattaforme per la produzione di Oil&Gas è sempre più sotto l’attenzione mediati- of the productive state of offshore ca e rappresenta una criticità sociale, ambientale ed economica soprattutto ai fini della definizione Oil&Gas platforms, through the di programmi di chiusura mineraria e dismissione degli impianti. E’ diventato necessario individuare evaluation of the national database in modo oggettivo e sistematico una terminologia per definire lo stato dell’impianto in termini di una of the Italian Ministry of Economic sua utilità alla produzione e coltivazione del giacimento oltre che definire un metodo scientifico di Development – Directorate General classificazione per lo studio statistico delle piattaforme. In letteratura esistono terminologie utilizza- for safety of mining and energy acti- te da parte degli addetti ai lavori per la definizione di un pozzo petrolifero; al contrario non esistono vity (DGS-UNMIG). ancora degli standard internazionali e dei criteri univoci per definire lo stato produttivo delle piatta- From the DGS-UNMIG databa- forme. Questo lavoro propone una terminologia che potrebbe essere adottata dalle Amministrazioni se, in this study we suggest the fol- italiane per la definizione dello stato produttivo degli impianti offshore, elaborata analizzando la banca dati nazionale degli impianti a mare attraverso un progetto di collaborazione nell’ambito lowing nomenclature for platform degli accordi per la sicurezza offshore della DGS-UNMIG del Ministero dello Sviluppo Economico state (Fig.1): con enti di ricerca, università, e corpi delle Stato. 1. Active/productive state: the Parole chiave: classificazione, Oil&Gas, piattaforme, terminologia, dismissioni. platform is active and connected to production wells. 2. Inactive state: the platform is inactive and related only to non- 1. Introduction organizations, etc.). One of the main production wells. Such state is to problems is the misunderstanding ori- be considered for decommissio- A scientific and technical debate ginated from non-operational offsho- ning. about the need to adopt a termino- re platforms. A practical example is 3. Standby state: the combination logy for Oil&Gas wells started back the northern Adriatic Sea platforms of the productive state of the plat- in the 1940s. The current classifica- case. In this region, several platforms form and productive state of wells tion for hydrocarbon wells does not are not operational because of the results in uncertainties on the in- consider the necessity of the Admi- existence of administrative impedi- clusion as Active or Inactive state nistration of clear terminologies to ments, even if their production could due to technical or administrati- identify the productive state of wells be potentially relevant. How should ve reasons. This state needs to be and platforms in order to ensure tran- we consider those types of platforms? verified case-by-case consulting sparency and diffusion of data to all In this paper, we try to apply the clas- the expert opinion of the DGS- relevant stakeholders (civil society, sification proposal to a case study in UNMIG competent Authority to local administration, environmental the northern Adriatic Sea. decide in which category to inclu-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 109-113 109 environment

development going from probable to possible and then to proven reserves. The Lahee nomenclature considers both technical and economic aspects discriminating between the risks associated with the exploration/production phases of a new reservoir and the exploration/production phases of a new level of a well-known reservoir. Taking into account the risks, the Lahee classification considered the scope and the success of wells (e.g. explorative, development and production well – discovery, development or abandoned well). Fig. 1. Schematic representation of three States of an offshore platform as a result In addition to the previous ones, of the combination between the “productive state” classification of “wells” and “plat- another class is about suspended forms”: inactive; productive; “STAND BY” (i.e. the non-production plants need to be wells. In this category all un-clas- checked for the state of the plant from the technical and administrative points of sified wells are found at the end of view). It is important to point out that the chart contains all the possible combinations year; even though they have reached but not all of these are actually real cases. Marked with (*) the unreal cases. the expected depth (for example Rappresentazione schematica dei tre stati delle piattaforme risultati dalle combinazioni those waiting for a production test). tra la classificazione dello stato produttivo dei pozzi e la classificazione delle piattaforme: Furthermore, if in the past the non attive; produttive; “STAND BY” (condizioni di non produttività degli impianti che neces- problem of wells had already been sitano di una verifica dello stato dell’impianto dal punto di vista tecnico e amministrativo). dealt with and resolved by the Mi- È importante sottolineare che il grafico riporta tutte le combinazioni possibili ma che non nistry adopting the aforementioned tutte queste sono effettivamente dei casi reali. Con il Simbolo (*) sono evidenziati i casi nomenclature for statistical reviews, inesistenti. no common standard for the status of offshore platforms has been defined or adopted yet. de platforms and consequently to (AAPG) and the American Petro- One of the possible immediate decide the potential decommis- leum Institute (API). The use of a platform classifications is the one sioning of the plant. shared nomenclature for the sector related to the connection to one or These three definitions are the has an influence on management more wells (Table 1). results of all possible combinations and administration at internatio- By considering this classification between two different classifica- nal level, furthermore, to define a the relevance for a terminology of tions subsequently illustrated (one common standard for the symbols the relation between platforms and of “wells” and one of “platforms”). to adopt in the official cartography wells is clear. In particular, how is a Not all the categories in figure 1 reproduction (PPDMA, 2012). platform with all or some non-pro- present a real case. In the following The debate started due to the ducing wells classified? paragraphs, the methodologies used great number of existing classes of As an offshore platform is a plant to obtain the three states and a case wells in function of the life cycle with the purpose of exploiting a re- study in northern Adriatic Sea will of a petroleum project. It is impor- servoir through wells, then the “probe explained. tant to notice that the life cycle of ductive state” of a platform can be a petroleum project is linked both defined considering the state of the to technical and economic aspects related wells. associated with the estimation of For the above reason, the termi- 2. Methodology hydrocarbon reserves. nology used by the DGS-UNMIG to The exploration phase, prior to define the productive state of wells is The terminology used by experts drilling activities of the exploration considered in this study in first place. in the hydrocarbon sector is the well, is characterized by unproven In detail, table 2 shows the termi- Lahee nomenclature of 1944, used resources, not (or roughly) estima- nology used by the DGS-UNMIG as a standard also by the American ted, while the uncertainties about taking into account the technical Association of Petroleum Geologists reserves gradually decreases with nomenclature (http://unmig.mise.

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Tab. 1. Relationship between platform type, size and number of connected wells. gas extraction. This last category of Rapporto tra tipo di piattaforma, dimensioni e numero di pozzi allacciati. support, when linked to platforms Platform typology Average dimension (m) N. connected wells defined as inactive and then no longer useful to production, could be Mono-tubular 8x8 1 considered for decommissioning. Bi-tubular 19x4 2 The inactive platforms are defined as those completely associated with Cluster - 24 and that do not have to support pro- Submarine well head - 0 duction. The novelty is the addition of the inactive platform as a new independent state of a platform. This gov.it/unmig/pozziattivi/st.asp) as sible to represent the classification represents a support for a clearer ter- follows: adopted as in figure 2 in which “Po” minology to facilitate the dialogue – Production well: a well that is stands for “wells” and “Ptf” stands for with stakeholders; while at technical drilled with a good result. The platforms: level, it is useful to clearly indicate well is defined productive after its – “Po” includes producing “PoE” that a platform could be conside- completion and it remains pro- and non-producing “PoNE”; red for a possible decommissioning ductive until its mining closure; – “Ptf” includes active “PtfA” and plan due to motivated non-utility – Producing well: a production well inactive “Ptf NA”. criteria (over time) in terms of the that is currently extracting hydro- Oil&Gas platforms are mainly ac- plant’s production. The application carbons from the reservoir; tive or inactive. Among the active of the terminology to the DGS- – Non-producing well: a produc- ones, useful platforms for production UNMIG database has been carried tion well that is not currently are those productive or potentially out, alongside the development of extracting hydrocarbons from the productive or useful also for other lo- the above-described theoretical con- reservoir. gistical support functions for oil and struction. Firstly, it was implemen- – Non-operative wells: are wells that have potentiality and could Tab. 2. Terminology proposed for the productive state of a hydrocarbon well. be productive but because of ad- Proposta di terminologie per indicare lo stato produttivo di un pozzo petrolifero. ministrative impediments are not Well state Definition (DGS-UNMIG) active now. – Non-productive wells: are wells Production Producing a well drilled with a good result. The producing well is a without potentiality or of no eco- (active) production well that is currently extracting hydrocarbons nomic interest. or injecting fluids from/to the reservoir. As practice suggests, the produ- Non-producing a well drilled with a good result. The non-producing cing and non-producing states may (suspended) well is a production well that is not currently extracting vary several times during the lifetime hydrocarbons from the reservoir of a production well. Therefore con- Non-operative (suspended) Non-operative wells are wells that have good potentiality sidering different states allows to de- and could be productive; but because of administrative fine the transient phases of the pro- impediments are not active now. duction well when, due to technical/ safety reasons, a period of inactivity Non-productive Closed about Non-productive wells are wells without potentiality or could occur as requested by the ope- (inactive) to close considered to be not economically viable (Sterile). rators under the authorization and the supervision of Mining Authori- Tab. 3. Terminology proposal to define the productive state of a hydrocarbon platform. ties (in Italy the DGS-UNMIG). Proposta di terminologie per indicare lo stato produttivo di una piattaforma petrolifera. The second step is the definition Platform state Definition of a classification for the productive state of a platform based on the ter- Active Connected to production (one or more producing or non-producing wells). minology used for the classification Non operative In areas subject to regulatory constraints or pending the granting of the of the productive state of wells (Ta- exploitation concession ble 3 takes into account the definitions of Table 2). Inactive Not useful for producing a field or it does not support the production of Following the terminology indi- a complex platform cluster. Related to all non-productive wells or non- cated in table 2 and table 3 it is pos- producing wells (for more than 5 years)

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Tab. 4. Correlation between wells and platforms in the A.C 17 .AG exploitation license ning. The situation of the case study and application of the classification proposal. is graphically reported in figure 3. Correlazione tra le tipologie dei pozzi e delle piattaforme presenti nella concessione di coltivazione A.C 17 .AG e applicazione della classificazione proposta. Platform Producing wells Non producing wells Platform state 4. Conclusions Giulia 1 1 Inactive Regina 6 Active This approach needs to be com- Regina 1 1 Active pared with other similar databases to those of the DGS-UNMIG in order to give consistency to the clas- ted individually to the “wells” and the mining statistical review, we il- sification. Nevertheless, the classifi- “platforms” categories and then in lustrate the case study of A.C 17 AG cation is intuitive and has practical combination. The number of com- exploitation license in the northern use. This work has placed for the binations in Figure 1 were obtained Adriatic Sea, related to the “REGI- first time at a technical/scientific after the definition of the two classi- NA” reservoir. From the database level the question of terminology fications in Figure 2 and by the com- of DGS-UNMIG we obtain the fol- to describe the productive state of bination of all categories obtained lowing situation (Table 4): platforms, and tries to give a pre- for the “Ptf state” and “Po state”. – “Giulia platform” (Ptf) is linked liminary solution to the problem. For the definition of a decom- to a non-producing well (PoNE) There are some criticalities related missioning plan for the standby and – “Regina platform” (Ptf) is linked to the specific features of a single inactive platforms, other important to six producing wells (PoE) platform for which an assessment criteria should be considered along – “Regina 1 platform” (Ptf) is lin- on technical characteristics of field with technical ones. ked to one producing well (PoE) development should be considered Using the classification propo- case-by-case by the competent Au- sal for this case study it is possible thorities. However, the Authorities to define the “Giulia 1” platform may make first considerations based 3. Case study as inactive because it is related to on the inactivity and standby state a non-producing well not linked to of some platforms and the non-pro- Using this method, tested on the the platform; despite the other two ductivity of related wells. Particu- DGS-UNMIG database, a new clas- platforms are still active because Re- larly an “inactive” state is defined sification for wells and platforms gina is linked to all producing wells for the first time. This state is impor- and their related productive state and Regina 1 is linked to a tempora- tant for transparency reasons for the is defined. To understand how the ry non-producing well. Consequen- Authorities. Furthermore, it can be classification can be applied to a partly, the “Giulia 1” platform should be significant to define a decommissio- ticular situation and also in view of considered for possible decommissioning plan. In addition, the “Stand- by” state could be and innovative term to introduce to all stakeholders such case of long life infrastructures potentially productive but non- producing (or other types of combination). The Authority should be cautious in order to establish a time when platforms are considered almost active (even if they are linked to all non-producing wells) or on the contrary when platforms have to be considered inactive. An operative platform is another important category derived from the classification proposal: it is not productive Fig. 2. Schematic representation of the classification of “wells” and “platforms” produc- only for technical administrative tive state. reasons and could have relevant Rappresentazione schematica della classificazione dello stato produttivo dei pozzi e delle potentiality. Finally, this work pro- piattaforme. vides some definitions and a method

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Fig. 3. Example of the application of the classifying method to the A.C 17 .AG exploitation license. Esempio grafico dell’applicazione del metodo classificatorio alla concessione A.C 17 .AG. to interpret data about wells and UNMIG of the Italian Ministry of PoNO – non-operative well platforms as well as to understand Economic Development). PoNA – non-active well whether they could be considered PoNCH – well towards closure for a decommissioning plan. PoCH – closed well Acronyms PtfA – active platform PtfPR – productive platform PoPR – PoA – production well or ac- PtfNPR – non-productive platform References tive well PtfS – support platform to the pro- PoNP – PoNA non-production well duction Lahee, F.H., 1944. Classification of ex- or inactive well PtfO – operative platform ploratory drilling and statistics for PoE – producing well PtfNO – non operative platform 1943, «American Association of PoNE – non-producing well PtfNA – inactive platform Petroleum Geologists. Bulletin», Vol. 28, pp. 701-721. PPDM ASSOCIATION, 2012 – Wells status & classification. Acknowledgement Web links This paper is conceived and funded by the Italian Ministry of Economic Devel- opment within the partnership of the “Network for Offshore Safety”. The authors http://unmig.mise.gov.it/unmig/ gratefully acknowledge the valuable support of Division VI and Division II of the pozziattivi/st.asp (accessed Directorate General for Safety and National Mining Office (DGS-UNMIG) of the 22/08/2017 at web of DGS- Ministry of Economic Development.

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L. Serri* Use of renewable energy D. Bertani* F. Colucci* in offshore Oil&Gas S. Guastella* platform for power supply E. Lembo* * Ricerca sul Sistema Energetico – optimisation RSE S.p.A., Milan, Italy

RSE carried out a research activity concerning the exploitation of renewable energy sources in the marine sites of the Italian operating Oil&Gas platforms with the aim to partially or totally satisfy The use of renewable energy can their electricity consumptions, abate atmosphere emissions and foster a “greener” Blue Economy. be realized as indicated hereunder: The activity was carried out two phases, described in the present paper. The first phase concerned – installing RES electrical gene- the assessment of the offshore renewable resources in each of the more than 130 operating off- ration devices directly on the shore Oil&Gas platform sites and the development of a dedicated GIS (Geographical Information platform, using the suitable space System) tool, whose data have already been published. The second phase concerned the study of either on emerged or submerged renewable power supply in a pilot case, the AZALEA B platform in the Adriatic Sea. Different energy portions of the platform structure, mixes with photovoltaic and small-wind plants were considered with and without storage systems. – the integration of these devices Power production, renewable penetration and costs were analysed considering the seasonal fluctua- in / on the platform, is referred to tions of wind and solar resources available at Azalea B offshore site. as “hybrid platform”; Keywords: offshore platforms, Oil&Gas, offshore renewable resources, GIS, energy mix. – providing external devices (at sea L’impiego di energie rinnovabili nell’ottimizzazione energetica di piattaforme off and / or on the nearby coast) able shore Oil&Gas. RSE ha condotto un’attività di ricerca sull’uso di energie rinnovabili nei siti delle to meet the energy demand of one piattaforme Oil&Gas operative nelle acque italiane con lo scopo di soddisfare, parzialmente o total- or more neighbouring platforms mente, il loro fabbisogno energetico, di abbattere le emissioni in atmosfera e di sostenere una “più characterized by significant elec- verde” Blue Economy. trical consumptions – this is the L’attività si è articolata in due fasi, descritte nel presente articolo. La prima fase è consistita nella case of “sharing area”, namely stima delle risorse rinnovabili in ciascuno dei più di 130 siti offshore in cui sono presenti piattaforme sharing of marine area; Oil&Gas operative e nello sviluppo di uno strumento GIS (Geographical Information System) dedi- – providing the integration/combi- cato, i cui dati sono già stati pubblicati. La seconda fase è consistita nello studio dell’alimentazione, nation of the aforesaid solutions. tramite energie rinnovabili, di una piattaforma, AZALEA B situata nel Mar Adriatico, scelta come As regards the first item, some com- caso pilota. Sono stati considerati differenti mix energetici con impianti fotovoltaici e mini-eolici, con plications could arise for the physical e senza sistemi di accumulo. Sono stati analizzati la produzione energetica, la penetrazione delle rinnovabili e i costi considerando le fluttuazioni stagionali della produzione eolica e fotovoltaica integration of RES conversion devi- specifiche del sito pilota. ces in the operative platforms, due to Parole chiave: piattaforme offshore; Oil&Gas, risorse rinnovabili offshore, GIS, mix energetico. the possible interferences with the systematic activities, to the lack of available space and to the high risk related to the extraction activities. 1. Introduction platforms (Lembo et alii, 2015 and As regards the second item, pos- 2016) (Bertani et alii, 2016) with sible conflicts with already existing MISE DGS-UNIMIG (the Italian the aim to partially or totally satisfy activities-transport, fishery, military, Ministry of Economic Development, their electricity consumptions, abate and “new” ones-aquaculture, future Directorate General for Safety – Na- atmosphere emissions, contribute to extraction platforms, RES plants, in tional Mining Office for Hydrocar- the decarbonisation path and foster the platform area could arise. bons and Georesources), funded a a “greener” Blue Economy [1]. Different time integration scena- big research project concerning the rios can be performed related to the safety of offshore plants compliant technological maturity of RES devi- with the Italian Legislative Decree 1.1. RES power supply of ces: n.83 (June, 26 2012). In this frame, Oil&Gas platforms – Short Term Scenario (current): RSE carried out a specific research small size wind turbines (3÷20 activity on the use of RES (Renewa- The offshore RES considered in kW rated power) and photovol- ble Energy Sources) in the marine si- this study are wind, solar, waves and taic (PV) plants integrated into tes of the Italian operating Oil&Gas marine currents. existing structures (operative

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platforms, storage ships located exploitation and hydrocarbons annual energy production (RSE near the platforms), taking into extraction, with possible reduc- ATLAEOLICO [4]); account the available space; tion/concentration of the envi- – maps of the solar radiation in- – Medium Term Scenario (within ronmental impact and increase of cident either on the horizontal five years): multi-megawatt wind the acceptance of offshore plants plane or on the optimal tilt plane farms characterized by fixed (Holahan, 2008). (source PVGIS – JRC [5]); foundations (shallow water) in- The main cons can be identified – map of the average annual power stalled offshore, close to a plat- as follows: available from wave motion (RSE form group or at the coastline fa- – increase of the overall risk due to TRITONE [6]); cing the area; the performing of different activi- – map of the specific annual ave- – Long Term Scenario (more than ties in the same platform/area; rage marine current power flow five years): multi-megawatt wind – delays / difficulties in obtaining (RSE TRITONE [6]). farms on floating platforms for the necessary permissions for the Offshore extractive platform deep waters and device arrays ca- installation of RES conversion MISE DGS-UNMIG database [7], pable to capture energy from waves devices, mainly due to the ex- bathymetry map and administrative and currents (these technologies pected involvement of different boundaries were also implemented are still at a prototypal stage [2]). authorities in the permission pro- into the GIS project. Depending on the distance cess; The bathymetry map was clas- from the shore and on the presence – uncertainty about the timing of sified in three water depth bands: of an electrical connection betwe- the achievement of technologi- shallow waters (0-30 m), where fi- en the platforms and the mainland, cal maturity of some technologies xed foundations – typically mono- RES energy production plants can (floating wind energy systems, piles, are used; transitional waters be stand-alone or grid connected, waves and marine currents energy (30-50 m), where fixed foundations as shown in (Svendsen et alii, 2011) conversion). – typically jackets, are used and deep and (Lorentzen, 2013). In the stand- The research activity was carried waters (50-200 m), where floating alone case, the introduction of an out in two phases. The first phase, structures are expected to be used. energy storage system is essential to described in Chapter 2, concerned In the GIS tool, a dedicated query achieve a higher penetration of RES the assessment of the offshore rene- was developed in order to extract the in the energy mix and maintain the wable resources in each operating information characterizing RES in necessary stability of the power sup- offshore Oil&Gas platform. The se- each platform site. As an example, ply. cond phase, described in Chapter 3, the result of this query is shown in It is worthwhile pointing out concerned the study of RES power Figure 1 for the Azalea B platform. that some applications concerning supply in a pilot case, the AZALEA The GIS data have already been the installation of PV plants on ac- B platform, operating in the Adriatic published and are freely accessible tive platforms have already been re- Sea in front of Rimini municipality. from MISE DGS-UNMIG site [8]. alized [3].

1.2. Pros/cons of renewable 2. Offshore renewable 3. Pilot case: energy mix power supply of Oil&Gas resource assessment optimisation for AZALEA B platforms through GIS tool platform The main pros of the integration 3.1. Platform choice and of RES for energy mix optimization Renewable resources assessment characteristics of Oil&Gas offshore platforms can at the offshore platform sites was car- be recognized as follows: ried out by means of a specially deve- The Azalea B platform was cho- – reduction of greenhouse gases loped GIS tool. This tool was mainly sen to perform the first pilot study emissions into the atmosphere; built on the basis of the offshore re- because of the availability of wind – cost reduction for RES offshore newable resource maps already deve- measurements carried out by the plants due to the sharing of infra- loped by RSE within the framework owner (ENI) with a sonic anemo- structure and logistics of already of previous research activities. In meter and a LIDAR (LIght Detec- operating or new platforms; particular, the following renewable tion And Ranging) device [9]. The – densification and concentration resources maps were implemented: results of the measuring campaign of the uses of a marine area, as – maps of the long term annual were integrated with a wind resource a result of the combined RES wind speed and of the specific assessment through mesoscale mo-

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3.2. RES and storage devices characteristics Due to the characteristics of Aza- lea B platform, the integration of three small wind turbines (rated power less than 10 kW) was considered. The turbine models were chosen as the best performing ones among 27 horizontal axis and 16 vertical axis models analyzed. Regarding the PV generator, two cantilever support structures, mechanically secured to the platform, were assumed as installed on the two sides facing Southeast and Southwest, with a 30° module inclination .A crystalline silicon PV module was chosen among commer- cially available modules for offshore applications. For the lower electrical load scenario, the optimal PV plant size was set at 26 kWp, while in the other case at 39 kWp. In Figure 2 a rendering of the integration of PV plant and wind turbines on the platform is shown. Fig. 1. Results of RSE GIS tool query for Azalea B platform. Lithium batteries were chosen as Risultati della “query” nel GIS per la piattaforma Azalea B. storage system. del RAMS (Regional Atmospheric Modelling System [10]) performed by RSE. The annual average wind speed turned out to be around 5 m/s at 50 m a.s.l. The solar resource was extracted by PVGIS [5]. The marine renewable resources were considered inadequate for energy production in this site and therefore were not included in the energy mix. Given the lack of information, the following assumptions about the platform characteristics were made: – the platform is along the direction WNW-ESE; – 10 kW and 20 kW of constant load are two typical daily electricity consumption profiles; – the current generation system is composed of two diesel generators (one for redundancy) with a rated power of 15 kW and 30 kW, for each electricity consumption sce- Fig. 2. Rendering of wind turbines and PV plants integration in the Azalea B platform. nario. “Rendering” degli impianti fotovoltaici e mini-eolici integrati nella piattaforma Azalea B

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3.3. Energy mix analysis €/h/kW; Hor./Vert. wind turbine value of 1,434 annual equivalent capex: 30/25 k€/unit and opex: 500 hours. However, during the central Energetic and economic simula- €/unit/yr; PV capex 2 k€/kW and hours of the day, the combined pro- tions of different energy mixes with opex:50 €/kW/yr; Li-Ion battery ca- duction of the two plant sections (SE and without storage, were carried pex 1 k€/kWh and opex 50 €/kWh/ – SW) exceeds the power absorbed out with an appropriate simulation yr; battery converter capex 300 €/ by the loads, forcing PV inverters to software (HOMER Pro®, Hybrid kW and opex 20 €/kW/yr. operate in “derating mode”, limiting Optimization Model for Electric Simulation results, in case of hi- the power generated by PV modules Renewables [11]). The optimal solu- gher platform energy consumption and reducing the equivalent hours tion for each configuration was then (20 kW), are shown in Table 1 for to 1,098 (the excess energy, equal to identified, using both energetic and different energy mixes without sto- the difference between the energy economic criteria listed below: rage (case B, C and D) and with theoretically producible and actual- – significant renewable energy pe- storage (case E-1, E-2 and E-3). Th- ly produced, is reported in Table 1 as netration, and relevant reduction ree different storage capacities have “Energy Surplus”). of fuel consumption and, conse- been considered in E-1, E-2 and E-3 The introduction of wind genera- quently, of pollutants emissions; case. The results are all referred to tors shows a good complementarity – reduction, or modest increase, of the variations with respect to the of the two renewable sources (solar LCOE (Levelized Cost Of Ener- current configuration with only die- and wind). However, the local ave- gy). sel generation (reference case A, not rage wind speed does not seem suf- Economic inputs were assumed reported in the table). ficient to make the installation of as follows. Fuel price: 0.50 €/l; di- Configuration B (Diesel + PV) se- wind turbines convenient from an scount rate: 2.5%; inflation rate: ems the only one able to achieve a economic point of view, since their 0%; diesel gen. capex (capital ex- reduction of LCOE. The good levels introduction in the energy system penditure): 500 €/kW and opex of solar irradiation would allow the involves a slight increase in LCOE (operational expenditure): 0.03 PV generator to reach the satisfying values. This is mainly due to the low

Tab. 1. Azalea B: simulation results in case of higher platform energy consumption (20 kW – 175,200 MWh/yr). Azalea B: risultati delle simulazioni nel caso di più elevati consumi della piattaforma (20 kW – 175,200 MWh/yr). Unit B C D E-1 E-2 E-3 Diesel+PV Diesel+PV+ Diesel+PV+ Diesel+PV+ Diesel+PV+ Diesel+PV+ Wind MV1 Wind MH1 Wind MH1+ Wind MH1+ Wind MH1+ EESS EESS EESS Diesel Gen. – Pn kW 60 60 60 60 60 60 PV Gen. – Ptot kW 39 39 39 39 39 39 Wind Gen. – N. turbine # 0 3 3 3 3 3 Wind Gen. – Pn kW - 5 6 6 6 6 Wind Gen. Ptot kW - 15 18 18 18 18 Storage – N. battery # 0 0 0 30 60 120 Storage – capacity kWh - - - 19.5 39 78 PV – equivalent hours h/yr 1,098 1,119 1,117 1,276 1,282 1,388 Wind – equivalent hours h/yr - 1,766 2,074 2,367 2,380 2,575 ΔLCOE %* -0.5 7.7 6.1 1.5 6.6 15.8 RES penetration respect to the load % 24.4 39.9 46.2 52.2 52.4 56.5 Energy Surplus respect to the load % 7.5 11.3 13.1 6.5 6.3 1.9 Energy Surplus of RES output % 23.4 21.9 22.1 11.0 10.6 3.2 Fuel consumption reduction %* 22.5 36.5 42.5 50.0 50.4 54.2 * variation with respect to base scenario (Diesel only) Legend: PV photovoltaic module; Wind MV1 and MH1: best performing vertical and horizontal axis wind turbine; EESS: Li-Ion batteries.

Dicembre 2017 117 environment fuel cost and to the presence of a si- storage system, in case of configura- platforms is a process that can con- gnificant energy surplus. The hori- tion E-3. The so-called “time shift” tribute to the decarbonisation of the zontal-axis wind turbine appears to is the possibility of accumulating energy system. It can also make the be the most efficient in terms of equi- the excess renewable energy genera- Blue Economy greener and therefore valent hours of operation, if compa- ted and using it in a different time more acceptable. red with the vertical-axis one. Besi- of day. The batteries are completely A GIS tool was developed star- des purely economic considerations, charged by RES generation during ting from wind and marine energy the hybrid configuration (C, D, E in the central hours of the day. They maps already developed by RSE at Table 1) is particularly favourable give their contribution in supplying national level, in order to carry out from an energetic and environmen- the load from h. 17:00, with a gra- offshore renewable resources asses- tal point of view. For example, con- dual increase of the power output sment at the Oil&Gas platform si- figuration D (Diesel+PV+Wind (negative value in the graph) as the tes. MH1), is able to reach a high level of production from the PV generator A pilot case was considered in or- renewable energy penetration (over declines. In this situation, the pre- der to apply and test a methodology 46% of final energy consumption), sence of batteries together with the for the optimisation of the energy allowing a consistent reduction of abundant generation by wind turbi- mix including “traditional” fossil fuel consumption and of the conse- nes, avoids the re-ignition of the ge- fuelled electric generation, renewa- quent greenhouse gases emissions, nerator in the evening hours, using ble generation and storage systems. thanks to the aforementioned com- the renewable energy accumulated Both RES penetration and econo- plementarity of wind and sun availa- during the day. mic indicators were taken into ac- bility profiles. count for the above mentioned op- Typical daily trends of the per- timisation. In the best configuration, formance of generation and storage a penetration of renewable energy systems involved in the energetic 4. Conclusions of more than 50% can be achieved mix were simulated as well. The with a negligible increase of the cost graphs in Figure 3, represent a typi- Renewable power supply of of- of energy. cal “time-shift” application of the fshore operating Italian Oil&Gas

References

Bertani, D., Lembo, E., Serri, L., Gua- stella, S., Panei, L., Terlizzese, F., 2016, Renewable Power Supply of Offshore Oil&Gas Plants in Italy: Resource Assessment and Power Supply Optimisation, 3rd Offshore Energy and Storage Symposium, OSES 2016, Malta July, 13-15. Holahan, T., 2008, A Framework for Alternative Energy Development: Shifting From Drilling Rigs to Renew- ables, 35 B.C. Envtl. Aff. L. Rev. 321, http://lawdigitalcommons.bc.edu/ ealr/vol35/iss2/6. Lembo, E., Serri, L., Bertani, D., Gua- stella, S., Gelli, C., 2015, Ottimiz- zazione energetica degli impianti offshore. Contesto, risorse rinnovabili, tecnologie, scenari, progetto GIS, Rapporto RSE, Prot. 15010022. Fig. 3. Typical high-RES-generation day: electric load and generation (above); battery Lembo, E., Serri, L., Bertani, D., Gua- power and state of charge (SOC) (below). stella, S., 2016, Ottimizzazione ener- Tipica giornata con alta produzione da fonti rinnovabili: carichi e generazione elettrica getica degli impianti offshore.Caso (alto); potenza e stato di carica (SOC) delle batterie (sotto). di studio: impianti FER per l’alimen-

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tazione della piattaforma Azalea B, Websites accessed on date [5] http://photovoltaic-software. Rapporto RSE, Prot. 16002027. August, 16 2017 com/pvgis.php Lorentzen Kolstad, M., 2013, Inte- [6] http://map.rse-web.it/tritone/ grating Offshore Wind Power and [1] https://ec.europa.eu/maritimeaf- map.phtml Multiple Oil and Gas Platforms to fairs/policy/blue_growth_en [7] http://unmig.mise.gov.it/unmig/ the Onshore Power Grid using VSC- [2] https://www.ocean-energy- strutturemarine/piattaforme.pdf HVDC Technology, NTNU – Master systems.org/library/annual-re- [8] http://unmig.mise.gov.it/unmig/ of Science in Energy and Envi- ports/document/oes-annual-re- accordi/rse/ottimizzazione.asp ronment. port-2016/ [9] http://newweb.riminifiera.it/ Svendsen, H.G., Øyslebø, E.V., Ha- [3] http://www.enipower.it/it/pages/ upload_ist/AllegatiProgrammaE- diya, M., Uhlen, K., 2011 Integration attivita-fotovoltaiche/applicazio- venti/Eni_846678.pdf of offshore wind farm with multiple ni/utenze-isolate/utenze-isolate. [10] http://rams.atmos.colostate. oil and gas platforms, PowerTech, shtml edu/ IEEE Trondheim. [4] http://atlanteeolico.rse-web.it/ [11] http://www.homerenergy.com/

Acknowledgement Financial support from the Italian Ministry of Economic Development DGS-UNMIG under the project “Safety of offshore plants” is gratefully acknowledged.

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S. Camporeale* LNG loading/downloading I. Antoncecchi* A.S. Bonetti* and circular economy: the F. Ceruti* opportunities related to the * University of Milan, “Bicocca” on secondment to Ministry of Economic new legislation and the reuse Development DGS-UNMIG; Milano of Oil&Gas platforms Decree no. 257/2016 transposing The purpose of this paper is to survey national regulatory framework development and the existing the Directive 2014/94/EU on the technical knowledge for the possible reuse of hydrocarbon platforms at the end of their useful life as construction of an alternative fuel base for the loading and unloading of liquefied natural gas (LNG) onto ships. This objective, in line infrastructure, defines (Article 1) with the main national strategic objectives (National Energy Strategy – SEN, 2013) for the promo- LNG as alternative fuel and foresees tion of the energy mix and decarbonisation, could be a great opportunity for Italy considering the the possibility to use existing ener- role natural gas will play in the coming years and, particularly, the opening up of the world market gy infrastructures for LNG loading to LNG. Together with its economic interest, the prospect of reusing existing hydrocarbon offshore and unloading activities. Article platforms is made even more attractive as it poses an answer to social and environmental issues 13, paragraph 5 of the aforementio- addressed by European policies, mainly in Circular Economy (Action Plan UE, 2015), Blue Growth ned Legislative Decree says that “the and safety of mining activities in terms of platform removal. This goal is at the forefront, but the provisions of the decree, subject to com- concrete potential is still marginally dealt with due to new legislation (Legislative Decree no. 257 of 16 December 2016) which is not yet matched by adequate economic feasibility studies in Italy. This pliance with environmental, landscape, document will illustrate the regulatory developments that have taken place over the last months for public health, safety and public safety the possible conversion of Oil&Gas platforms for LNG loading and unloading. rules, shall apply to projects for the con- Keywords: LNG, platforms, reuse, decommissioning, circular economy. struction of existing infrastructure and energy sites for LNG storage and subse- Carico/scarico di GNL ed economia circolare: le opportunità connesse alla nuova quent downloading on vessels”. The normativa e il riutilizzo delle piattaforme Oil&Gas. Il presente lavoro ha lo scopo di effet- purpose of this paper is therefore to tuare una ricognizione dell’evoluzione normativa nazionale e delle conoscenze tecniche attualmen- verify whether production platforms te esistenti ai fini del possibile riutilizzo delle piattaforme di produzione di idrocarburi, al termine can be considered suitable sites for della loro vita utile, come base di carico e scarico di gas naturale liquefatto (GNL) per le navi. Tale the LNG loading and unloading obiettivo, in linea con i principali obiettivi strategici nazionali (Strategia Energetica Nazionale – activities at the end of their useful SEN, 2013) di promozione del mix energetico e di decarbonizzazione, potrebbe rappresentare una life and if they can be considered as grande opportunità per il Paese considerando il ruolo che il gas naturale è destinato a ricoprire nei prossimi anni e, in particolare, l’apertura del mercato mondiale al GNL. Contestualmente all’inte- energy infrastructures. resse economico, la prospettiva di riutilizzo degli impianti già esistenti in mare è resa ancora più There are three reasons that sup- attrattiva per la sua risposta ad altre tematiche sociali ed ambientali affrontate dalle politiche eu- port the above: ropee principalmente attraverso scelte di economia circolare (Piano di Azione UE, 2015), Crescita 1) an Oil&Gas platform is a rig for Blue e sicurezza delle attività minerarie in termini di rimozione degli impianti. Si tratta di un obiettivo hydrocarbon exploration and all’avanguardia le cui potenzialità concrete sono ancora marginalmente trattate a causa dell’evolu- production. In particular, pro- zione normativa (Decreto legislativo 16 dicembre 2016, n. 257) ancora da recepire tecnicamente e duction platforms can be fixed alla mancanza di adeguati studi di fattibilità tecnico economica in Italia. In questo documento sarà infrastructures, installed for full illustrata l’evoluzione normativa intervenuta in questi mesi e i principali elementi tecnici da conside- exploitation of a field (fixed piled rare per la possibile riconversione delle piattaforme petrolifere per l’attività di carico/scarico di GNL. platform); Parole chiave: GNL, piattaforme, riutilizzo, dismissioni, economia circolare. 2) the term infrastructure refers to the complementary buildings necessary for carrying out a socio- 1. Introduction global context. This role is mainly economic activity; due to the favourable geographical 3) Law 239/2004, Article 1, para- The Italian National Energy Stra- position of Italy in the middle of graph 2, says that Energy activi- tegy (SEN, 2013) rose, according to the Mediterranean Sea and to the ties consist on the distribution of the energy mix and decarbonisation relative important maritime routes electricity and natural gas, explo- goals, the role of Italy as European around it. In order to ensure the use ration, exploitation, underground hub for the use of LNG in a growing of alternative fuels, the Legislative storage of hydrocarbons, and

120 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 ambiente

transmission and dispatching of show the existing legislation to be 2.1. LNG: an economic electric power, granted under li- considered for the conversion of overview cense in accordance with the law. hydrocarbon platforms for LNG use Converting and reusing plat- in order to have a better understan- In 2015, global production of na- forms is an innovative perspective ding of the topic. The work is sui- tural gas hit a record high of 3,590 for Italy, especially if considering the table every time research faces new Billion cubic metres (Bcm) a 1.6% basic principles of a Circular Eco- problems and/or themes on “which growth compared to the previous nomy (CE) which can be defined little or no previous research has year (International Energy Agency, as a “regenerative system in which been done” (Brown, 2006). The fol- 2016). The Organisation for Econo- resource input and waste, emission, lowing sources of information have mic Co-operation and Development and energy leakage are minimised been used: (OECD) as a whole is the main by slowing, closing, and narrowing 1. National Energy Strategy: for a producer of natural gas. However material and energy loops. This can more competitive and sustainable Europe has registered a decrease of be achieved through long-lasting energy of the Ministry of Econo- –2.5% between 2014 and 2015 (In- design, maintenance and repair, mic Development, March 2013; ternational Energy Agency, 2016). reuse, remanufacturing, refurbi- 2. Consultation paper on LNG Na- Regarding prices, in 2015, natural shing, and recycling” (Geissdoerfer tional Strategy of the Ministry gas import prices by pipeline fell et al., 2017). Although reduction, of Economic Development, June by an average of 27.2% for Europe- recycling and reuse are the three key 2015; an Union members (International principles of CE, it should be noted 3. Legislative Decree no. 257 of 16 Energy Agency, 2016). As stated by that, at a practical level, the transi- December 2016 transposing the the International Energy Agency in tion towards CE seems more focused Directive 2014/94/EU on the 2015, global demand for natural gas on recycling rather than reusing. construction of an alternative fuel showed a growth of 1.4%, to about However, according to the waste infrastructure; 3,600 Bcm as well as in OECD whe- hierarchy proposed by Hansen et al. 4. Legislative Decree no.145 of 18 re natural gas demand was 1.0% hi- (2002), reusing is more of a priority August 2015 transposing the Di- gher when compared to 2014. This than recycling (Zawawi et al., 2012) rective 2013/30/EU “Offshore Di- increase was mainly attributable to and more environmentally friendly rective”. Europe, where consumption rose by than disposal. Moreover, by reusing, 3.4%, especially in Italy (+5.6 Bcm), it is possible to reduce environmen- France (+2.3 Bcm), and Germany tal impact as well as revitalize com- (+2.2 Bcm). Regarding imports, in petitiveness of local economies and 2. Liquefied Natural Gas 2015, although within the OECD improve people’s well-being (Stahel, LNG imports decreased by 4.4%, 2013; Castellani et al., 2015). In this LNG (Liquefied Natural Gas) is in Europe imports by pipeline rose context, reuse can be considered as a clear, colorless and non-toxic li- by 21 Bcm (+7.9%). Focusing on a new step in life cycle, made up of quid which forms when natural gas Italy, Figure 1 illustrates the main four different stages: Design, Con- is cooled to –162 °C (-260 °F). The indicator of LNG in the period struction, Operation/Maintenance, cooling process shrinks the volume 1973-2015. Data shows a decrease in Decommissioning (Labuschagne & of the natural gas 600 times. Conse- LNG production, but an increase in Brent, 2005). Over the years, some quently, it is easier and safer for ope- consumption. Considering the series researches have dealt with reuse, in rators to store and ship LNG. The li- since the 1990s, consumption rose the circular economy perspective, quefaction process involves the by 42.4%, while imports doubled. of industrial plants/ platforms at the removal of certain components, end of their life cycle (Jepma, 2015; such as dust, acid gases, helium, wa- Gaugenrieder et al., 2017). In this ter, and heavy hydrocarbons, which 2.2. Small Scale LNG framework, this study can be consi- could cause difficult downstream. dered an exploratory research regar- When LNG reaches its destination, “Small Scale LNG” (or SSLNG), ding the reuse of Oil&Gas platforms it is turned back into gas at regasi- is the method through which LNG as base for LNG loading/unloading fication terminals. This makes LNG is handled directly in liquid form onto ships. It should be noted that cost efficient and convenient to with respect to the regasification this work aims at providing the main transport over long distances where carried out in dedicated terminals elements of the reuse of Oil&Gas pipelines do not exist. LNG is stored and the subsequent introduction of platforms without reaching a final in cryogenic tankers, sea vessels or the gaseous product into the tran- and definitive solution. Due to the road tankers (Consultation paper on sport network (Consultation paper novelty of the issue, the idea is to LNG National Strategy, 2015). on LNG National Strategy, 2015).

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90000 LNG bunkering is the practice of Producon 83097 Consupon providing LNG fuel to a ship for its 80000 74915 own consumption. The key advan- Imports 70745 70069 70000 Exports 75354 67523 tage of LNG as a fuel is the vast re- 61912 67725 60000 duction in pollutant caused by the 61966 61201 more traditional method of fuelling 47405 57447 55757 50000 ships such as heavy fuel oil, marine diesel fuel and marine gas oil. The 40000 30470 main bunker options for the LNG 30000 refuelling for shipping sector product 20000 17095 17296 and the necessary infrastructures are 16633 15407 8406 8605 (Consultation paper on LNG Natio- 10000 7735 7149 18 50 6771 nal Strategy, 2015): 2008 141139 228 237 221 A. Truck-To-Ship (TTS) 0 0 B. Shore – Pipeline – To Ship 1973 1990200020102012201320142015P C. Ship to Ship (STS) Fig. 1. LNG in Italia (1973-2015). Dati in miliardi di metri cubi, fonte: International D. by mobile cisterns or ISO cryoge- Energy Agency, 2016. nic containers LNG in Italy (1973-2015). Data in Bcm, Source: International Energy Agency, 2016. In particular, and for the purpose of this paper, the option Ship to the objectives set by the Directive says that “sea operations in the hydro- Ship (STS) which is the transfer of 2014/94/EU. It should be noted, carbons” are “all activities related to the LNG from a ship or boat, with LNG however, that achieving an efficient installation or related infrastructure, as a load, to another vessel for use as and effective distribution needs the including the planning, construction, fuel could represent a good model. realization of infrastructures capa- operation and maintenance and dispo- In fact, the main advantages of this ble of making available natural gas sal of the project relating to the explo- type of transfer are the ability to ope- in liquid form. These infrastructures ration and production of hydrocarbons, rate at sea even without coming into should be suitably located conside- excluding the transport of hydrocarbons the port, if weather conditions and ring the best logistic scenario that from one coast to the other”, and fi- wave motion allow it. It is suitable comprehends the national territory nally, by Article 25, paragraph 6 of for big and medium sized ships with including the sea: an important fo- Legislative Decree no.104 of 16 June high transfer capacity, and LNG sto- cus should be given to the alternati- 2017, (“Environmental Impact As- rage facilities not needed although ve fuel for marine traffic. The Natio- sessment”), which says that the Mi- closely linked to the large import- nal Strategic Framework, attached nistry of Economic Development, in export terminals. (Clean Transport to the Legislative Decree, says that agreement with the Ministry of the – Support to the Member States for for the purpose of hypothesized long- Environment and the Sea and with the implementation of the Directive term logistic scenarios, the possibi- the Ministry of Cultural Heritage on the Deployment of Alternative lity of using and re-converting exi- should adopt the national guideli- Fuels Infrastructure Good Practice sting infrastructures for LNG storage nes for the decommissioning of plat- Examples, European Commission must be taken into account. This forms in order to ensure the quality January 2016). Similarly, it is easy to hypothesis appears in the Italian sce- and completeness of the assessment imagine a similar bunker solution re- nario for the first time. The limit is of their environmental impacts. In garding LNG loading and unloading represented by the fragmentation of the Italian Legislation there are not on reused offshore platforms at the applicable rules. In fact the conver- many administrative procedures for end of their useful life. sion of Oil&Gas platforms for LNG LNG development, such as the con- storage purposes should also take version of Oil&Gas platforms into into account the lack of a detailed LNG storage for the purpose of loa- decommissioning regulation. Today ding and unloading onto ships. Cur- 3. Results decommissioning represents an in- rently, Legislative Decree 257/2016 teresting topic for the hydrocarbon establishes the simplification of ad- The introduction of the afore- sector. Decommissioning has recen- ministrative procedures for national mentioned Legislative Decree no. tly been addressed by Legislative De- LNG storage and transport infra- 257/2016 is, for the first time, an in- cree no.145 of 18August 2015 which structures (Article 9) and those not novative device to reduce fossil fuel transposes the Directive 2013/30/ concerning the supply of natural gas emissions. LNG distribution can si- EU “Offshore Directive” and which transport networks (Article10). The gnificantly contribute to achieving in Article 2, paragraph 1, lett. gg) authorization must be granted accor-

122 Dicembre 2017 ambiente ding to: of LNG in the areas of transport, the supply and distribution industry – LNG storage equal to or greater land and sea, and that of industrial (Consultation paper on LNG Natio- than 200 tonnes is authorized by and civilian large-scale users can nal Strategy, 2015). the Ministry of Economic Deve- mean a progressive replacement of It can therefore be said that in lopment in coordination with Mi- energy products with a benefit both the future LNG carriers from all nistry of Infrastructures and Tran- in terms of greenhouse gas emis- over the world, without necessarily sport and Regions; sions effect and fine dust emissions entering the main Italian ports, can – LNG storage less than 200 tonnes and NOx and SOx, in the field of unload LNG to be stored in partial- and equal to or greater than 50 transport. It must also be said that ly dismantled platforms then sent to tonnes is authorized by Regions; plant operators subject under the ports by supplying tankers or isocon- – GNL Storage less than 50 tonnes Integrated Environmental Autho- tainers for subsequent LNG distri- is authorized by municipalities. rization (AIA-IPPC) regulated by bution. By reusing Oil&Gas plat- Therefore, based on the stora- the Legislative Decree no.152 of 3 forms at the end of their life cycle, ge capacity of an offshore Oil&Gas April 2006 and, more generally, all it is possible to respect the principle platform, further analysis is needed business that operate facilities with of nothing that contains useful ma- by other authorities involved in the emissions are required to perform terial is lost (Frosch, 1992). In fact, administrative procedure particu- periodic monitoring to check and CE aims at preventing the loss of larly in relation to the conversion of verify emissions. It could be argued materials (Mirabella et al., 2014) Oil&Gas platforms. Therefore, it is that as far as atmospheric emissions and considers waste as a potential possible to imagine a new LNG di- and water emissions are concerned, resource (Park and Chertow, 2014; stribution involving partially remo- the plants are similar but involve dif- Zaman and Lehmann, 2013). Of ved Oil&Gas platforms. According ferent pollutants and different legal course, the concrete technical pos- to Legislative Decree no. 257/2016 limit values. Furthermore, it should sibility to carry out LNG logistics Italy has to reach (Article 6) within be pointed out that, due to the small requires further engineering, econo- 31 December 2030, a number of size of a platform and possible plant mics, environmental and safety stu- LNG supply points in maritime ports limitations, it is more likely to reuse dies. Research and feasibility studies to allow inland navigation of vessels plants as “local storage” (without a are desirable, through a case-by-case or LNG-powered seagoing vessels in regasification plant) and this would approach in collaboration with bu- the TEN-T (Trans European Net- lead to the hypothesis of reducing sinesses/companies, contributing work – Transport). In this regard, it emissions to a minimum. to the development of the subject, should be noted that TEN-T net- which is at its early stages. work includes in the Adriatic Sea, Ravenna and Ancona Ports where there is the highest number of plat- 4. Conclusions forms which will be disposed. The- References refore, we can imagine LNG distri- Based on the current legislative bution involving partially removed framework and technical knowled- Brown, R.B., 2006), “Doing Your Dis- platforms, LNG storage, bunker bar- ge, it is possible to imagine that, in sertation in Business and Manage- ge for LNG loading and unloading. theory and taking into account all ment: The Reality of Research and To develop LNG distribution there the necessary technical assessment, Writing”, Sage Publications. are numerous technical variables to there is a concrete future opportu- Castellani, V., Sala, S., & Mirabella, N., consider: the size and weight of the nity for Italy to become a reference 2015). Beyond the throwaway platform to be modified and used point in the world for LNG in the society: A life cycle-based asses- for LNG loading and unloading ac- transport and industrial sectors. sment of the environmental bene- tivities, storage capacity and size The impact that LNG deve- fit of reuse. Integrated environmen- and bunker dimensions and cha- lopment may have in the Italian tal assessment and management, racteristics, type or size of the ship, economy can be identified by a bo- 11(3), 373-382. safety standards and environmental ost to the metal-mechanical engine- European Commission (2016), Cle- protection carrying out all the ope- ering sectors specializing in the use an Transport – Support to the rations. As far as the environmental of special steels, as well as in design Member States for the imple- aspects are concerned, it should be and construction of storage and di- mentation of the Directive on the noted that LNG is a clean, sulfur- stribution of cryogenic liquids, naval Deployment of Alternative Fuels free fuel whose molecular simplicity shipbuilding – with an offer on in- Infrastructure Good Practice allows clean combustion with very ternational markets of products de- Examples. low solid residues. The availability veloped for domestic needs – and for European Parliament (2013/30/EU),

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Directive on safety of offshore oil Ministry of Economic Development Stahel, W.R., 2013). Policy for mate- and gas operations. (2013), Italy’s National Energy rial efficiency-sustainable taxation European Parliament (2014/94/EU), Strategy: for a more competitive as a departure from the throwa- Directive on the deployment of and sustainable energy. way society. Phil. Trans. R. Soc. A, alternative fuels infrastructure. Ministry of Economic Development 371(1986), 20110567. Frosch, R.A., 1992). Industrial ecology: (2015), Consultation paper on Zaman, A.U., & Lehmann, S., 2013). a philosophical introduction. Pro- LNG National Strategy. The zero waste index: a perfor- ceedings of the national academy of Mirabella, N., Castellani, V., & Sala, S., mance measurement tool for sciences, 89(3), 800-803.Gaugenri- 2014). Current options for the va- waste management systems in a eder, S., Pellegrino, C., Copello, S., lorisation of food manufacturing ‘zero waste city’. Journal of Cleaner 2017), Condition Assessment for waste: a review. Journal of Cleaner Production, 50, 123-132. Offshore Platforms Reuse, Pro- Production, 65, 28-41. Zawawi, N.A.W.A., Liew, M., & Na, K., ceedings of Offshore Mediterranean Park, J.Y., & Chertow, M.R., 2014). 2012). Decommissioning of offshore Conference and Exhibition, 29-31 Establishing and testing the “reuse platform: A sustainable framework. March, Ravenna, Italy. potential” indicator for managing Proceedings of the Humanities, Geissdoerfer, M., Savaget, P., Bocken, wastes as resources. Journal of envi- Science and Engineering (CHU- N.M., & Hultink, E.J., 2017). The ronmental management, 137, 45-53. SER), IEEE Colloquium on. Circular Economy – A new sustainability paradigm? Journal of Clea- ner Production, 143, 757-768. Hansen, W., Christopher, M., & Ver- buecheln, M., 2002). EU waste policy and challenges for regional and local authorities. Ecological Institute for International and European Environmental Policy: Berlin, Ger- many. International Energy Agency (2016), Natural gas information. Italian Parliament (2000), Legislative Decree n. 164 of 23 May 2000 (G.U. n. 142, 20-6-2000). Italian Parliament (2006), Legislative Decree no. 152 of 3 April 2006 (G.U. n. 88, 14-4-2006 – Suppl. Or- dinario n. 96). Italian Parliament (2011), Legislative Decree n. 93 of 1 June 2011 (G.U. n. 148, 28-6-2011 – Suppl. Ordina- rio n. 157). Italian Parliament (2016), Legislative Decree n. 257 of 16 December 2016 (G.U. n. 10 del 13-01-2017 – Suppl. Ordinario n. 3) Jepma, C.J., 2015), Smart sustainable combinations in the North Sea Area (NSA). Make the energy transition work efficiently and effectively, Energy Delta Institute (EDI). Labuschagne, C. & Brent, A.C., 2005), Sustainable Project Life Cycle Management: the need to integrate life cycles in the manufactu- Acknowledgement ring sector, International Journal of The present study is funded by the Ministry of Economic Development (DGS Project Management, 23, 159-168 UNMIG) in the framework of the “Network for offshore safety”.

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D. Di Bucci* The SPOT project (potentially I. Antoncecchi** F. Ciccone** triggerable offshore seismicity G. Teofilo** and tsunamis): a first appraisal F. Terlizzese** A. Argnani*** of the possible impact of oil M. Ligi*** M. Rovere*** and gas platforms on the R. Basili**** M. Coltelli***** seismic and tsunami risks S. Lorito**** B. Borzi****** along the Italian coasts F. Germagnoli****** M. Di Ludovico******* G.P. Lignola******* The SPOT Project (potentially triggerable offshore seismicity and tsunamis) is aimed at helping A. Prota******* Italian authorities to comply with the application of the Safety of Offshore Oil and Gas Operations European Directive (2013/30/EU) and the ensuing Italian codes. An extensive reconstruction of * Dipartimento della Protezione Civile, offshore geological structures is being implemented in order to assess the existence of potentially Roma, Italy seismogenic faults in the surroundings of offshore oil and gas platforms, as a propaedeutic step for ** Directorate-General for Safety of the assessment of potentially triggered seismicity connected with operations on such platforms. mining and energy activities, Roma, Italy The descriptive parameters of the identified faults will be used to estimate their natural earthquake *** CNR-ISMAR, Bologna, Italy rates. The impact of these natural earthquakes along the coasts will then be modeled in terms of **** INGV-Roma1, Roma, Italy expected ground shaking and tsunamis. In turn, these models will be used to estimate potential hu- ***** INGV-Catania, Catania, Italy man and economic losses in a multi-hazard approach to risk assessment. Wherever the combined ****** EUCENTRE, Pavia, Italy earthquake and tsunami modeling indicates a relevant impact along the coasts, a more detailed ******* ReLUIS, Napoli, Italy analysis will be carried out, also involving the operators of the related platforms, to perform specific models which also take into account production data. The project has been conceived and funded by the Italian Ministry of Economic Development, with the technical support of the National De- partment of Civil Protection. The involved research institutes are the Institute of Marine Sciences of the National Research Council (ISMAR), the National Institute of Geophysics and Volcanology 1. Introduction (INGV), the European Centre for Training and Research in Earthquake Engineering (EUCENTRE), and the Laboratories University Network of Seismic Engineering (ReLUIS). The SPOT project (potentially Keywords: hydrocarbons, offshore safety, seismic risk, tsunami risk, Italy. triggerable offshore seismicity and tsunamis; in Italian: Sismicità Po- Il progetto SPOT (Sismicità Potenzialmente innescabile Offshore e Tsunami): una tenzialmente innescabile Offshore prima valutazione del possibile impatto delle piattaforme a olio e gas sul rischio sismico e da tsunami lungo le coste italiane. Il progetto SPOT (Sismicità Potenzialmente e Tsunami) has been conceived by innescabile Offshore e Tsunami) è destinato a supportare le Autorità italiane nell’applicazione della the Italian Ministry of Economic Direttiva Europea sulla sicurezza delle operazioni in mare nel settore degli idrocarburi (2013/30/ Development (Directorate-General EU) e dei decreti italiani che ne derivano. È in fase di elaborazione un’ampia ricostruzione delle for Safety of mining and energy acti- strutture geologiche offshore al fine di valutare l’esistenza di faglie potenzialmente sismogeniche in vities; hereinafter MiSE-DGS) with prossimità di piattaforme offshore di estrazione olio e gas esistenti, come fase propedeutica per la the technical support of the Natio- valutazione della sismicità potenzialmente innescata connessa con operazioni su tali piattaforme. nal Department of Civil Protection I parametri descrittivi delle faglie identificate verranno utilizzati per stimare il tasso di sismicità naturale ad esse associato. L’impatto di questi terremoti naturali lungo le coste sarà poi model- (DCP), following the auspices of lato in termini di scuotimento al suolo e maremoti (tsunami). A loro volta, questi modelli saranno the Italian Major Risks Commis- utilizzati per stimare le potenziali perdite in termini di vite umane ed economiche, attraverso un sion. This Commission represents approccio multi-hazard. Laddove la modellazione combinata dei terremoti e degli tsunami indichi the scientific advisory body of DCP. un impatto rilevante lungo le coste, verrà effettuata un’analisi più dettagliata, coinvolgendo anche gli After the 2012 Emilia earthquake, operatori, per eseguire modelli specifici che tengano conto anche dei dati di produzione. Il progetto the Commission suggested, among è stato ideato e finanziato dal Ministero dello Sviluppo Economico italiano, con il supporto tecnico other indications, to consider the del Dipartimento Nazionale della Protezione Civile. Gli istituti di ricerca coinvolti sono l’Istituto di Scienze Marine del Consiglio Nazionale delle Ricerche (ISMAR), l’Istituto Nazionale di Geofisica e triggered seismicity as a relevant and Vulcanologia (INGV), il Centro Europeo per la Formazione e la Ricerca nell’Ingegneria dei Terremoti primary issue, worth of the same at- (EUCENTRE), e la Rete Universitaria dei Laboratori di Ingegneria Sismica (ReLUIS). tention already devoted to induced Parole chiave: idrocarburi, sicurezza offshore, rischio sismico, rischio da maremoto, Italia. seismicity (Dialuce et al., 2014). The

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 125-131 125 environment

MiSE-DGS supervises the safety of faults. These tsunamis can be both cated in the Adriatic Sea, in the Io- the offshore hydrocarbon explora- directly generated by the seafloor di- nian Sea and in the Strait of Sicily. tion production platforms and it is splacement due to the fault, and by In these areas, we will analyze the interested in the potentially trigge- submarine landslides induced by sei- possible existence of active faults, rable offshore seismicity, as well as in smic shaking. For those platforms as- and their seismogenic and tsunami- the potential tsunami risk. For this sociated to particularly severe dama- genic potential. Moreover, the pos- reason, at the beginning of 2017, ge scenarios (if any), a further third sible contribution of seismic shaking the MiSE-DGS decided to fund a step can be envisaged, in which an to submarine landslides and their project aimed at addressing for the in-depth analysis has to be carried potentially ensuing tsunamis will be first time in Italy the problem of the out on the actual possibility that evaluated. potentially triggerable seismicity, in the related activities may trigger a Taking into account the identi- particular, the seismicity related to damaging earthquake. This requires fied areas, the engineering compo- the offshore platforms activities. that data provided by the operators nent of the project will acquire data have to be taken into account, along characterizing the building stock with the reconstruction of a geo- and selected infrastructures in terms mechanic model of the reservoir. of spatial distribution, typology and 2. State of the art This third step could be implemen- seismic vulnerability. The residen- ted successively, based on the project tial buildings will be also characteri- At present, the knowledge on the outcomes. The project is coordina- zed in terms of tsunami vulnerability. seismogenic faults in Italy does not ted by MiSE-DGS. DCP provides allow any predictive evaluation on advice and technical support, also the possibility that they may be trig- concerning the possible interactions gered by anthropogenic activities. with the Major Risks Commission. 4. Current activities and This topic, however, can be approa- The involved research institutes are first results ched starting from the characteriza- the Institute of Marine Sciences of tion of the natural major seismicity the National Research Council, the 4.1. CNR-ISMAR activities that could be expected due to the National Institute of Geophysics occurrence of potentially seismoge- and Volcanology, the European ISMAR has three tasks: 1. iden- nic faults in proximity of the hydro- Centre for Training and Research tify potentially active faults located carbon platforms, in our case those in Earthquake Engineering, and the nearby oil and gas offshore plants; located offshore the Italian coasts. Laboratories University Network of 2. identify submarine landslides and This is a natural seismicity that Seismic Engineering (hereinafter sediment instability along continen- could be potentially triggered by hu- ISMAR, INGV, EUCENTRE and tal margins, in the vicinity of the man activities. ReLUIS, respectively). Their con- offshore plants, that can be triggered Following this approach, the first tributions are described in Section 4. or enhanced by seismic shaking cau- step is the identification and cha- sed by the above mentioned faults; 3. racterization of possibly seismogenic modeling the tsunami wave possibly faults occurring near these plants, at produced by the seafloor displace- a distance that is compatible with 3. Study areas ment caused by marine landslides. a potential interference among The identified active faults will be human activities and faults. Once To identify the marine zones characterized in terms of seismoge- identified these major faults, based which represent the focus of the nic potential by INGV. Using the on the available data, and defined SPOT project, we started by consi- shaking scenarios elaborated by their descriptive parameters at best, dering all the offshore exploitation EUCENTRE, ISMAR will model the second step consists of the ela- licenses that are active, and we tra- the stability of sediments along the boration of a number of events and ced the related reservoir perimeters, slopes, based on sediment proper- damage scenarios related to the acti- that have been made available to ties. Whenever sediment instability vation of these faults, independently the MiSE-DGS by the operators. is resulting, especially in presence from any possible interaction with According to Dialuce et al. (2014) of preexisting landslide deposits, anthropogenic activities related to guidelines, we traced a buffer of 15 ISMAR will model the tsunami the operations carried out in the km from the previously identified re- potential due to sediment displace- platforms. Part of the project is also servoir perimeters. The obtained zo- ment. The maximum tsunami wave devoted to the possible occurrence nes (Figure 1), which are coalescent height inundating the coasts and the of tsunamis induced by earthquakes in many cases, define the study areas velocity and momentum flux will be caused by the triggered seismogenic of the project. These are mainly lo- computed and given to ReLUIS to

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of the Strait of Sicily study area; Fig. 1), based on ISMAR’s data interpretation, there is no evidence of faults in the upper sedimentary succession. Deeper structures, beneath the Gela nappe, appear neither to be active, nor reactivated. Unfortunately, in this area bathymetric data are not available on the shelf and along the slope, and this prevents a more accurate assessment. For this reason, the multichannel seismic profile CROP (CROsta Profonda) M23A will be re-processed with the aim of having a higher resolution image of the first 2 km of the sub-seabed, to solve possible upward extent of the deeper-se- ated structures. In the area surrounding the offshore platform Vega (to the North of Malta, Fig. 1), CHIRP sonar profiles show no evidence of a possible offshore prolongation of the Scicli-Ragusa fault system, mapped and well-known on land, nor any other clear deformation pattern. Several submarine landslides, with average maximum size of 60 km2, Fig. 1. Study areas. Areas were ISMAR data are available, are shown in the figure. Whe- are instead present along the eastern re possible, also further information will be used (VIDEPI database, bathymetries from slope of the Gela Basin. These sli- the Italian Navy Hydrographic Institute, etc.). See text for further details. des do not appear to be controlled Aree di indagine. Nella figura sono visualizzate le aree con i dati ISMAR. Ove possibile, or aligned along tectonic structures, verranno utilizzate anche altre informazioni (database VIDEPI, batimetrie dell’Istituto Idro- but suggest a predisposition of the grafico della Marina, etc.). Si veda il testo per ulteriori dettagli. margin to repeated and relevant, in terms of geo-hazard, mass-wasting build their scenarios. Active faults the oil and gas offshore platforms, processes. In the Ionian sea, around and evidence of sediment instabili- especially considering that a high the thermogenic gas exploitation ty will be mapped in the study are- resolution morphology of the seabed plants Luna and Hera Lacinia (to as using a large database of marine was not available when most of these the East of Catanzaro, Fig. 1), high geophysical and geological data, ac- exploitation facilities were designed resolution morpho-bathymetric data quired by ISMAR over a long time and constructed at sea. Geological indicate that the thrust front, which span (1990’s-today) consisting of maps are being compiled for each surrounds the Crotone promontory, (i) 100 x 103 km of high resolution of the study areas of the project, has been largely eroded on its sou- single-channel seismic reflection with associated shapefiles, comple- thern flank, where numerous gullies profiles (CHIRP and sparker), (ii) te with attributes, to be implemen- and slope channels are present. The- 30 x 103 km of multichannel sei- ted in the web-based GIS platform se features are interpreted to be pro- smic reflection profiles. 30 x 310 km2 provided by EUCENTRE. Some of of of a substantial inactivity of the of bathymetric data, some of which these maps are available from the thrust front. The most eye-catching characterized by high frequency Marine Geological Cartography for features in the area are, on the con- capable of sub-metric horizontal the Adriatic Sea, scale 1:250.000, trary, diffuse pockmarks and other resolution, will be also used for as- that ISMAR produced (Trincardi seabed elements due to the presence sessing seafloor evidence of deeper et al., 2011). Preliminary investi- of fluid flow at the seafloor, linked to deformation and fault systems. A gation over the Strait of Sicily and the deep gas reservoir, which is see- better understanding of the seafloor the Ionian Sea has provided some ping, most likely along normal faults. dynamics is of crucial importance interesting insights. In the area of These particular preconditioning to assess the geo-hazard playing on the Gela-Panda fields (western part factors (presence of fluids and abun-

Dicembre 2017 127 environment dant erosion at the seafloor) concur is represented by the coupling coef- bon production areas. To this aim, to trigger numerous relatively small ficient, a term necessary to convert EUCENTRE interacts with INGV landslides along the steep upper slo- the geological fault activity into sei- in order to obtain the parameters of pe that characterizes this area. smic activity. The geological activi- the potentially seismogenic faults. ty of potentially seismogenic faults This data is the input for the proces- will then be complemented with the sing of damage scenarios. EUCEN- 4.2. INGV activities analysis of the actual occurrence of TRE also interacts with ISMAR to past earthquakes by analyzing the in- share choices on creating seismic INGV’s main tasks are the geo- strumental and historical seismicity shaking scenarios, in order to allow logical identification and characte- (CPTI15, Rovida et al., 2016). We ISMAR to evaluate the potential ac- rization of potentially seismoge- also plan to investigate historical tivation of underwater instabilities nic faults, the assessment of their archives of the circum-Adriatic and capable, in their turn, to cause tsu- earthquake production rates, and Ionian Seas in search for evidence namis. Damage scenarios are genera- the modeling of tsunamis caused by that may clarify the location of some ted for areas of the coastline falling the sea-bottom displacement produ- critical events (e.g., 1612 earthqua- within a radius of 100 km from the ced by such earthquakes. ke of Rimini). considered offshore platforms. As To this end, INGV will interpret Ultimately, all these data will be a first approximation, we consider seismic reflection profiles (VIDEPI used as input to model the potential 100 km as the maximum radius of database), aided by the stratigraphy tsunamis generated by the mapped earthquake impact, also for impor- of well logs and other geophysical/ faults (Basili et al., 2013). After esta- tant magnitudes. Areas of interest geological data, both offshore and blishing the initial conditions resul- for damage and losses scenarios are onshore near the coast. The analysis ting from a given earthquake ruptu- shown in Figure 1. In these areas, will be focused on the recognition re, the tsunami propagation at open 1563 municipalities were identified. of the faults cutting the upper brit- sea is simulated by solving the linear The damage scenarios are defined tle crust, whose down-dip width version of shallow water equations for residential buildings, school bu- is in the range of those producing using benchmarked codes (Macías ildings, road network elements and earthquakes of engineering signifi- et al., 2017). The results of these si- port infrastructures. For residential cance based on common fault sca- mulations will be expressed in terms buildings the exposure data (num- ling laws (e.g., Leonard, 2014). The of the probability to exceed fixed ber of buildings, number of dwellings information collected on faults at values of the Maximum Inundation and population), and therefore the crustal depths will be integrated with Height (MIH, following IOC, 2016) results, are known at municipality the geomorphological analysis of the for prescribed return periods. At se- level. The school buildings, road bathymetries and the interpretation lected locations, these results could network elements and port infra- of shallow sedimentary successions also be used, depending on the needs structures are defined item by item and brittle structures performed by of the project and the availability of and with different levels of knowled- CNR-ISMAR (see Section 4.1). detailed topo-bathymetries, to pro- ge, since the project can be classified Where possible, the geological slip duce inundation maps (Lorito et al., as a large-scale vulnerability study. rates of such faults will be based on 2015). The number of items is such that it the restoration of deformed horizons Finally, the seismogenic fault pa- does not allow a complete level of of known age (Maesano et al., 2013). rameters will be transferred to EU- knowledge of all elements exposed The main results of these analyses CENTRE for the ground motion to earthquakes. The final outcomes will be incorporated in 3D models modeling (see Section 4.3), whereas will be provided in terms of human of seismogenic faults parameterized the results of the tsunami modeling and monetary losses. The first step in according to international practice will serve as input for evaluating the the procedure for assessing earthqua- (e.g., Basili et al., 2008, 2013). The tsunami impact by ReLUIS (see Sec- ke scenarios is the vulnerability relevant geological parameters of tion 4.4). analysis of potentially affected struc- seismogenic faults (length, width, tures and infrastructures, i.e. their strike, dip, rake, slip rate) will be propensity to be damaged if they are used to estimate the seismic moment 4.3. EUCENTRE activities subjected to seismic ground motion. rate Ṁs. The earthquake recurrence To achieve this target, fragility cur- model will be expressed by a fre- EUCENTRE has the role of de- ves of structures and infrastructures quency-magnitude distribution that fining the damage scenarios on the are needed, produced in this project balances the seismic moment rate coastal structures and infrastructu- or selected from the literature. An (Kagan, 2002a,b). The largest uncer- res as a result of earthquakes due to interaction with ReLUIS allowed tainty associated with this workflow faults located nearby the hydrocar- the characterization of the residen-

128 Dicembre 2017 ambiente tial building stock to be harmonized, scenarios of damage and loss as a available at the regional scale level. in order to produce coherent dama- result of specific tsunami events, However, a sensitivity analysis based ge and losses scenarios on the coast, both caused by seismogenic faults on typical ranges yielded to a simpli- for both earthquakes and tsunamis. and by submarine instabilities indu- fied assumption of a dissipation of 1 The second step consists of quan- ced by seismic shaking. To this aim, m of the wave height every 200 m tifying the shaking scenarios related continuous exchange of data and of awashed land from the coastline. to the potentially triggered events. knowledge is expected with other This information is intersected with Therefore, we have to know the re- research centers. In view of mo- the terrain profile to identify the levant seismogenic faults and their delling the tsunami actions on the inundated zones (e.g., assuming a 10 characteristics, as well as the GMPE structures at a regional scale level, m high wave, the maximum inunda- (Ground Motion Prediction Equa- the previous experience in terms of ted strip of land is maximum 2 km tion) of the seismic motion. Once damages caused by tsunami in recent wide (it can be smaller in case of to- the earthquake magnitude, seismo- times (particularly in Chile, Japan, pographic highs). genic fault geometry and kinematics and Sumatra; Ghobarah et al., 2006; Structural analyses will then be are known from ISMAR and INGV Cuadra and Ishiyama, 2012; Park carried out to assess the vulnerabi- analyses, the shaking scenarios can et al., 2012) has been particularly lity of typical structures. In particu- be calculated in the affected areas considered to identify both the rele- lar, based on a “large scale” level of through GMPEs. Based on this sha- vant parameters of the hazard (wave knowledge and on the reliability of king scenarios, tools able to calcula- heights, awash areas, effects of dif- the structural models, static or dyna- te the damage scenarios have to be ferent land roughness) and the po- mic analyses in the linear and nonli- developed. This third and final step tential collapse mechanisms, hence near fields will be performed. The derives from the previous two and the most appropriate methodologies level of detail should be consistent is the elaboration of damage scena- of structural analysis, also related with a regional approach as well as rios, which can be obtained by the to the level of detail expected for with the reliability of the expected convolution of (i) the vulnerability, this project. Some fragility curves tsunami wave heights (assumed as here quantified by means of fragility have been already developed based the only required information, avai- curves, taking into account the ex- on real damages after those events, lable with adequate degree of accu- posure database that describes the albeit the building stock in Italy is racy, also according to recent Japa- structures and infrastructures pre- expected to be quite different. Data nese Design Method of Buildings sent in the target areas, and (ii) the on the Italian building stock nearby for Tsunami Resistance – SMBTR seismic events, here quantified by the coasts is collected through spe- – Okada et al., 2005). The analyses the ground acceleration in the point cific surveys and by using informa- cover both local and global pheno- where the structures/infrastructures tion held by public administrations mena, and therefore the structural are located. or available from existing databases, and non-structural components will EUCENTRE’s main contribution with the aim of evaluating the main be assessed separately. In particular, to the SPOT project is given by the building typologies (e.g., reinforced a series of parametric analyses aimed estimation of the potential losses (li- concrete or masonry) and morpho- at identifying critical parameters for ves and monetary costs) due to sei- logical characteristics (number of the formation of global or local col- smic events potentially triggerable storeys, wall typologies, etc.), also lapse mechanisms will lead to the by human activities on the offshore related to the construction period definition of fragility curves. The de- platforms. This contribution is de- and seismic classifications (linked finition of vulnerability classes will livered through a web-based Geo- to the expected structural perfor- be strictly related to the available graphic Interface System (GIS). mances). The Central Statistics In- information, so as to fit the knowled- stitute database provides valuable ge level on the building stock. As data, however it is often aggregated said before, to ensure a consistency 4.4. ReLUIS activities and some efforts were devoted to between EUCENTRE outcomes better characterize it in the areas of on seismic scenarios and ReLUIS The main contribution of ReLU- interest. Concerning the tsunami outcomes on tsunami scenarios, the IS Consortium to this project is to scenarios, it depends on the evalua- two partners shared the definition perform analyses of the vulnerabili- tion of potentially inundated areas, of the main features of residential ty of coastal residential – reinforced for which different methods have buildings to generate a consistent concrete and masonry – structures been considered. The Energy Grade building stock for the two different within the areas of interest, due Line Analysis (suggested in ASCE parametric analyses of vulnerability. to the impact of tsunami waves. In 7 2016), in particular, is based on ReLUIS is particularizing such fea- particular, it is planned to analyze many wave parameters, not always tures (known at municipality level)

Dicembre 2017 129 environment by conducting, just in these weeks, the SPOT ambition to cover all the tures (Standards – Asce/Sei). ad hoc surveys along selected parts of Italian areas, potentially exposed ISBN: 9780784414248 / DOI: the coast. The final goal is the defi- to the considered hazards, has to 10.1061/9780784414248 nition of damage and loss scenarios be pursued taking into account the Basili R., Valensise, G., Vannoli, P., Bur- as a result of specific events by me- uncertainties due to the large scale rato, P., Fracassi, U., Mariano, S., ans of a detailed analysis, using the approach and consequent simplifica- Tiberti, M.M., Boschi, E., 2008. fragility curves and expected losses tions adopted in all of the activities. The Database of Individual Sei- estimations. This will allow for a Therefore, the expected results have smogenic Sources (DISS), version 3: comprehensive evaluation of tsuna- to be considered as a first screening, summarizing 20 years of research mis effects. useful to establish priorities for fur- on Italy’s earthquake geology. Tec - ther in-depth studies. They are in- tonophysics, doi: 10.1016/j.tec- stead neither suitable to provide to.2007.04.014. reliable evaluations at local scale, Basili, R., Kastelic, V., Demircioglu, M.B., 5. Expected innovative nor to undertake specific operational Garcia Moreno, D., Nemser, E.S., scientific steps activities. Petricca, P., Sboras, S.P., Besana-Ost- man, G.M., Cabral, J., Camelbeeck, T., Natural risks potentially indu- Caputo, R., Danciu, L., Domac, H., ced by human activities on offsho- Fonseca, J., García-Mayordomo, J., re hydrocarbon platforms are a new 6. Final remarks Giardini, D., Glavatovic, B., Gulen, L., issue and a challenge for Italy. To Ince, Y., Pavlides, S., Sesetyan, K., Ta- obtain detailed and reliable loss sce- The SPOT project is intended as a rabusi, G., Tiberti, M.M., Utkucu, M., narios, seismogenic faults, shaking- very first step, a starting point for an Valensise, G., Vanneste, K., Vilanova, induced submarine instabilities and in-depth analysis that can no longer S., Wössner, J., 2013. The Europe- tsunamis caused by both of them be postponed, considering the so- an Database of Seismogenic Faults have to be identified and properly cial implications borne by decisions (EDSF) compiled in the framework parametrized. Analogously, vulne- made in this field. These decisions of the Project SHARE. http://diss. rability of building stock and infra- have to take into account the safety rm.ingv.it/share-edsf/, doi: 10.6092/ structures has to be characterized of the population and of their territo- INGV.IT-SHARE-EDSF. over large portions of the coastal ter- ries on one hand, and the economic Basili, R., Tiberti, M.M., Kastelic, V., Ro- ritories, along with the exposure of development of the country on the mano, F., Piatanesi, A., Selva, J., Lo- those areas, given by the population other hand. It is clear that the path rito, S., 2013. Integrating geologic and the monetary value of directly the project began to walk down is fault data into tsunami hazard stu- and indirectly affected goods. scientifically long and difficult. It is dies. Nat. Hazards Earth Syst. Sci., In this perspective, the SPOT also evident that, in its future deve- 13(4), 1025-1050, doi: 10.5194/ project is moving towards innovati- lopment and under the supervision of nhess-13-1025-2013. ve steps from several points of view. the MiSE-DGS, it has to be approa- Cuadra, C., Ishiyama, S., 2012. An out- In Italy, this is the first study which ched in collaboration with the ope- line of RC buildings performance is aimed at obtaining quantitative rators. This allows to analyze in detail under tsunami triggered by the East results of anthropic-natural multi- and quantitatively (integrating pro- Japan Great Earthquake. WIT Tran- hazard impact scenarios, in terms of duction data and models in the de- sactions on The Built Environment, lives and monetary losses, all along veloped scenarios) the real possibility vol. 126, pp. 315-324. the Italian coasts. At the moment, that the hydrocarbon production ac- Dialuce, G., Chiarabba, C., Di Bucci, this multi-hazard approach is refer- tivities may, or may not, trigger dama- D., Doglioni, C., Gasparini, P., La- red only to natural hazards, namely ging events and, in case, to provide nari, R., Priolo, E., Zollo, A., 2014. earthquakes, submarine landslides sounded information to implement Indirizzi e linee guida per il moni- and related tsunamis, but it is ex- scientifically based countermeasures. toraggio della sismicità, delle defor- pected to evolve, in the future, to- mazioni del suolo e delle pressioni di ward a comprehensive multi-hazard poro nell’ambito delle attività antro- risk analysis. Moreover, the cha- piche. Gruppo di Lavoro istituito dal racterization of the residential buil- References MiSE il 27 febbraio 2014 nell’am- ding stock in terms of tsunami vul- bito della Commissione Idrocarburi nerability represents a pioneering ASCE 7 American Society of Civil e Risorse Minerarie (CIRM). http:// activity in Italy. Engineers, 2016. Minimum De- unmig.sviluppoeconomico.gov. Given the duration of the project sign Loads and Associated Crite- it/unmig/agenda/dettaglionotizia. and the amount of allocated funding, ria for Buildings and Other Struc- asp?id = 238

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Ghobarah, A., Saatcioglu, M., Nistor, I., T., Takai, S., and Hamabe, C., 2005. B., Gasperini, P., 2016. CPTI15, the 2006. The impact of the 26 Decem- Structural Design Method of Buil- 2015 version of the Parametric ber 2004 earthquake and tsunami dings for Tsunami Resistance (Pro- Catalogue of Italian Earthquakes. on structures and infrastructures. posed). The Building Letter, Nov., Istituto Nazionale di Geofisi- Engineering Structures, vol. 28, no. 2004, The Building Center of Japan ca e Vulcanologia. doi: http://doi. 2, pp. 312-326. – Building Technology Research org/10.6092/INGV.IT-CPTI15. IOC, Intergovernmental Oceano- Institute. Trincardi, F., Argnani, A., Coreggiari, graphic Commission, 2016. Tsu- Park, S., van de Lindt, J.W., Cox, A., 2011. Cartografia Geologica dei nami Glossary, 2016. Third Edition. D., Gupta, R., Aguiniga, F., 2012. Mari Italiani alla scala 1:250:000. Paris, UNESCO. IOC Technical Successive Earthquake-Tsunami Fogli NK33-5 Pescara, NK33-1/2 Series, 85. (English, French, Spa- Analysis to Develop Collapse Fragili- Ancona, NK33-8/9 Bari, NL33-7 nish, Arabic, Chinese) (IOC/2008/ ties. J. Earthq. Eng., vol. 16, no. 6, pp. Venezia, NK33-6 Vieste, NK33-8/9 TS/85 rev.2). 851-863, 2012. Bari. ISPRA – Servizio Geologico Kagan, Y.Y., 2002a. Seismic mo- Rovida, A., Locati, M., Camassi, R., Lolli, d’Italia. ment distribution revisited: I. Sta- tistical results. Geophys. J. Int., 148, 520-541, doi:10.1046/ j.1365246x.2002.01594.x. Kagan, Y.Y., 2002b. Seismic moment distribution revisited: II. Moment conservation principle. Geophys. J. Int., 149, 731-754, doi:10.1046/j.1365- 246X.2002.01671.x. Leonard, M., 2014. Self-Consistent Earthquake Fault-Scaling Relations: Update and Extension to Stable Con- tinental Strike-Slip Faults. Bulletin of the Seismological Society of Ame- rica, doi: 10.1785/0120140087. Lorito, S., Selva, J., Basili, R., Romano, F., Tiberti, M.M., Piatanesi, A., 2015. Probabilistic Hazard for Seismical- ly-Induced Tsunamis: Accuracy and Feasibility of Inundation Maps. Ge- ophysical Journal International, 200, 574-588, doi:10.1093/gji/ ggu408. Macías, J., Castro, M.J., Ortega, S., Escalante, C., González-Vida, J.M., 2017. Performance Benchmarking of Tsunami-HySEA Model for NTH- MP’s Inundation Mapping Activities. Pure and Applied Geophysics, 174(8), 3147-3183, doi: 10.1007/ s00024-017-1583-1. Maesano, F.E., Toscani, G., Burrato, P., Mirabella, F., D’Ambrogi, C., Basili, R., 2013. Deriving thrust fault slip rates from geological modeling: exam- Acknowledgement ples from the Marche coastal and We kindly acknowledge Fabio Trincardi, Carlo Doglioni, Gaetano Manfredi and offshore contraction belt, Northern Riccardo Pietrabissa, who signed the agreements with the Ministry of Economic Apennines, Italy. Marine and Petro- Development on behalf of CNR, INGV, ReLUIS and EUCENTRE, respectively. leum Geology, doi: 10.1016/j.mar- The contents of this paper represent the Authors’ ideas and do not necessarily petgeo.2012.10.008. correspond to the official opinion and policies of the Italian Ministry of Economic Okada, T, Sugano, T., Ishikawa, T., Ohgi, Development and the National Department of Civil Protection of Italy.

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R. Cianella* Key performance indicators C. Brambilla** F. Cappelletti** and multicriteria approach V. Cozzani*** for measuring safety of A. Crivellari*** P. Macini*** offshore Oil&Gas facilities S. Maran** A. Tugnoli*** A. Saracino*** The present work aims to develop a composite indicator which allows quantifying and monitoring F. Terlizzese* over time safety performance of Oil&Gas production facilities located in the Italian seas. The proposed methodology has different phases and starts from the definition of significant risk compo- * Ministry of Economic Development, nents and of a logic tree-structure, in order to identify a set of Key Performance Indicators (KPIs), Directorate General for Safety of Mining related to the overall safety performance of upstream operations. After the definition of the different and Energy Activities – National Mining KPIs, based on the available data, their aggregation into a single composite indicator was carried Office for Hydrocarbon and Georesources out by means of a multicriteria approach. A first set of indicators, presented in this study, is related ** Ricerca sul Sistema Energetico – to the matters concerning the occupational safety, the inherent safety for major accident risks and RSE S.p.A., Department of Sustainable environmental impact and finally to the monitoring of installations by the Authorities. The proposed Development and Energy Sources *** University of Bologna, Department methodology shows the opportunity to consider further types of indicators or impact categories, so of Civil, Chemical, Environmental and that the composite indicator can capture all the issues related to the overall safety performance of Material Engineering production Oil&Gas facilities. Keywords: key performance indicators, multicriteria approach, offshore Oil&Gas facilities, tree of impacts, safety.

Indicatori chiave di prestazione e approccio multicriteriale per misurare la sicurezza concerning the entire offshore plat- delle installazioni offshore Oil&Gas. Il presente lavoro è finalizzato a sviluppare un indica- form fleet located in the Italian seas. tore composito che permetta di misurare e monitorare nel tempo la performance di sicurezza In the operative formulation, the delle istallazioni di produzione Oil&Gas presenti nei mari italiani. Il metodo proposto parte dalla composite indicator will be updated definizione delle componenti significative di rischio e di una struttura logica ad albero, per iden- annually by data collected during tificare un insieme di Key Performance Indicators (KPIs), legati alla performance complessiva di the previous year. sicurezza delle attività upstream. Dopo la definizione dei diversi KPIs, sulla base dei dati disponibili, The used approach is adapted la loro aggregazione in un unico indicatore composito è stata effettuata adottando un approccio multicriteriale. Un primo insieme di indicatori, definito nel presente articolo, riguarda aspetti legati from a methodology proposed by alla sicurezza occupazionale, alla sicurezza intrinseca per il rischio di incidente rilevante, all’impatto Tugnoli et al. (Tugnoli et al., 2008) ambientale ed infine al controllo delle piattaforme da parte delle Autorità. La metodologia proposta for the quantitative assessment of presenta l’opportunità di considerare anche ulteriori tipologie di indici o di categorie di impatto, così sustainability KPIs in the analysis che l’indicatore composito possa cogliere tutti gli aspetti correlati alla performance globale di sicu- of alternatives during the early sta- rezza delle installazioni di produzione Oil&Gas. ges of chemical and onshore O&G Parole chiave: albero degli impatti, approccio multicriteria, indicatori chiave di performance, piat- plant design. Offshore platforms taforme offshore per Oil&Gas, sicurezza. show similarities to these kind of processes (e.g. used technologies, hazardous material handled), but 1. Introduction of a set of KPIs which can be used specific characteristics have to be to check over time different fields of carefully addressed (e.g. unmanned The paper presents a methodo- offshore safety in upstream industry; plants, worker transportation, con- logy based on Key Performance In- the second one is the development gested spaces). Moreover, the me- dicators (KPIs) proposed, within the of a rigorous procedure which al- thodology for the development of scope of the project titled “Indicator lows combining the above mentio- the composite indicator from the for Offshore Safety”, in order to provi- ned KPIs in a composite indicator, KPIs is taken from the Handbook de the Italian authority responsible used to get an immediate and com- of the Organisation for Economic Co- for upstream safety with an effective prehensive picture of the evolution operation and Development (OECD, tool to monitor offshore Oil&Gas over time of the safety performances 2008), applying for this specific case (hereinafter O&G) facilities. Speci- in the sector. a multicriteria approach (Girardi et fically, two goals have been establi- The calculation of the composite al., 2014). shed: the first one is the definition indicator is based on aggregate data In order to check criticalities and

132 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 ambiente find solutions, a prototype of a com- ther development of the work, the curring in member companies and posite indicator was developed with structure will be populated with se- contractors since 1985 (IOGP, a minimum number of KPIs and veral categories of indicators, such 2015). with an half-yearly period for data as the KPIs related to the inherent The proposed indicators belon- collection. safety issues for major accident risks ging to the tree-structured metho- and environment impact. dology allow understanding several dimensions of injury phenomena. Such KPIs provide an assessment 2. Definition of the tree of 2.1. Occupational safety KPIs of both features related to the fre- impacts and set of KPIs for offshore O&G facilities quency (number of events related to worked hours) and features related A systematic procedure based on The purpose of occupational sa- to the severity such as the number of the definition of a tree“ of impacts on fety indicators is to assess the safety injuries and/or fatalities. Furthermo- safety” (Figure 1) was proposed for performance of work activities in re, the set of KPIs is non-redundant, the identification of a generalized offshore O&G facilities. Workpla- which means that each indicator hi- set of KPIs. In the first step of the ce safety depends on various factors ghlights different features. procedure, the reference basis and (employees’ behaviour, process con- the process boundaries are defined. dition, operator experience and trai- Next, a specific set of primary ca- ning, etc.). It is difficult to quantify 2.1.1. Lost Time Injury Frequency tegories of impact and a correspon- the aspects related to workplace safe- (LTIF) dent set of KPIs are selected (stem- ty through indicators, because not all ming phase).The development of a related data are measurable. For this The first indicator is called LTIF, tree-like structure was inspired to a reason, the development of occupa- which stands for “Lost Time Injury similar representation of a hierar- tional safety KPIs has focused on the Frequency”. This indicator allows chic structure extensively applied definition of: i) a set of indicators as describing the frequency of inci- in safety, occupational safety, deci- much comprehensive as possible on dents which caused an injury at sion making and computer techno- the aspects of interest for occupatio- work. It is a measure of the number logy (Saracino et al., 2015; De Ville, nal incidents; ii) the identification of of events (fatalities and lost work 2006). Figure 1 shows a preliminary measurable indicators from available day cases, or rather an incident re- structure of the proposed tree of im- data; iii) the use, when possible, of sulting in at least 3 days off work) pacts on safety. A first set of KPIs scientifically approved KPIs. per million worked hours. Its use is concerns the occupational safety The state of the art in the occu- widely confirmed in the literature area. A second set of KPIs regards pational safety field shows that a set (see UNI EN 7249, which describes the patrols performed by the Italian of KPIs is required in order to repre- the frequency indicator as a statisti- Navy and Coast Guard and finally sent complex phenomena about in- cal indicator suitable to represent the third set is related to activities cidents at work. The UNI EN 7249 the average frequency of injuries). of inspection by the Ministry of standard (UNI EN, 2007) and the In this context, the term “incident Economic Development. As a fur- practices, adopted by countries ex- at work” is defined as a fortuitous perienced in offshore safety mana- event occurring during a work- gement, such as Norway (Petroleum related activity, which has caused Safety Authority Norway, 2016) and physical damage and it results in a United Kingdom (HSE, 2015), have person being unfit for work for mi- been considered in the development nimum 3 days after the day of oc- of KPIs. There is no doubt that the currence of the occupational injury. lack of a single procedure is crucial; LTIF indicator is calculated as: even though the indicators used by N different countries have similarities, LTIF 106 (1) there are much differences in the ap- E proach of measuring safety resulting from the lack of a common guideli- where N is the number of occurred ne. This is confirmed by industry ini- events (fatal or not) during the ex- tiatives, such as the annual reports of posure time and E is the value of the the International Association of Oil worked hours for all activities and Fig. 1. Example of “tree of impacts”. and Gas Producers (IOGP) which operations that take place on the of- Esempio dell’albero degli impatti. has collected data on incidents oc- fshore installations. The number 106

Dicembre 2017 133 environment is simply a factor which makes the fatal injuries (N) according to the sources (UNMIG) of the Ministry of number more practically readable. equation (3): Economic Development. These audits G are carried out in order to assess all LWDCseverity = (3) the aspects related, for instance, to 2.1.2 Fatal Accident Rate (FAR) N machine maintenance, emissions, the accuracy of the management of The second indicator is called the offshore facilities, etc. An indi- FAR, which stands for “Fatal Acci- 2.2. Monitoring KPIs for offshore cator called Intensity of the Inspec- dent Rate”. This indicator is also wi- O&G facilities tions is defined in the equation (7) as dely used in the literature (UNI EN a measure of the presence of public 7249, HSE, IOGP). It represents a Another important feature rela- officials on site, which is deemed to measure of the number of fatal acci- ted to the safety of offshore O&G fa- have an extended beneficial effect on dents per 100 million worked hours. cilities is addressed to their monito- the safety performance of the facility: ring by the Italian Authorities. The FAR indicator is calculated as for B dd N equation (2): Italian Navy and the Coast Guard II j jp,j (7) N monitor the areas surrounding the nc FAR f 108 (2) offshore plants by aerial and naval E patrols in order to ensure security where Np,j is the number of officials and safety of installations (detection which carried out the inspection j, where Nf is the number of acci- of unauthorized access to facilities ddj is the number of days spent by dents which involve at least one and to safety zones, functionality of the Authorities on site and nc is the fatality as a result of a work-related navigation aids, reporting of spills, number of offshore exploitation con- incident, during the exposure period etc.). Two indicators are defined to cessions. considered. This exposure period, represent patrolling magnitude by E, is the number of hours worked means of the hours (HH) dedicated in each offshore O&G installation to these activities; the indicators are during a representative observation the Intensity of Italian Navy patrols 3. Use of Multi-Criteria 8 period. Finally, the number 10 is a (IPIN) and the Intensity of Coast Analysis in the calculation factor that makes the number practi- Guard patrols (IPCG): of a composite indicator for cally readable. IP = HH (4) safety in offshore upstream Data collection for FAR evalua- IN tion is characterized by rare fatal IP = HH (5) events in the national context, which CG The next step in developing a requires observation period to be long A third indicator is defined in composite indicator of safety per- enough to have significant values. For order to assess the warnings repor- formance is the combination of this reason, in the calculation of FAR ted by the Authorities for each in- different data in a single indica- it was decided to consider a period of stallation. Such a KPI is defined by tor representing the overall safety observation equal to 10 years. the equation (6), named Intensity of performance of offshore platforms. Warnings: Starting from the guidelines published by OECD (2008), the working Bi Nwii 2.1.3 Lost Work Day Case Severity IW (6) group formulated this problem in the (LWDC severity) nc context of Multi-Criteria Analysis (MCA), which is commonly used in Finally, the third indicator is where Ni is the number of warnings the frame of decision making. the Lost Work Day Case Severity which are collected during the pa- It must be noted that the goal of (LWDC severity). It measures the trols, wi is a weight referred to the the present study is not to make a average number of lost days per non- severity of the warning and nc is the decision but rather to evaluate the fatal injury. This is a measure of the number of offshore exploitation con- degree of safety of offshore O&G ac- average severity of non-fatal injuries cessions. tivities in different years, developing widely used in the literature (UNI Besides the activities above descri- a composite performance indicator EN 7249, 2007; IOGP, 2015).The bed, the Italian Authorities are also and comparing the different per- LWDCs indicator is calculated from responsible for the inspections on formances. In this context, MCA is the sum of the lost days for each in- site, which are external audits carried used because it facilitates and simpli- jury occurred during the observation out by officials of theNational Mining fies the management of conflicting period (G) and the number of non- Office for Hydrocarbon and Geore- objectives. It helps in identifying the

134 Dicembre 2017 ambiente preferences of decision makers and the final ranking of the alternatives. final performance of the alternative. can be used to produce a ranking of In the decision making context, a The final stage of the MCA process different alternatives (Fülöp, 2005). project alternative represents a set of is the ranking of the alternatives and The classical Multi Criteria Analysis actions that the decision maker can the selection of the best one, based (Keeney &Raiffa, 1993), is a metho- operate to condition the future. In on the reached scores. In the frame of dology that assigns a score to each al- the present application, each alterna- this Project, the MCA approach was ternative, based on the performance tive represents the safety performan- implemented through the Sesamo of the alternative itself in relation to ce in a fixed period of time (usually, software (Grasso & Maran, 2012). In properly selected evaluation crite- one year). Once the alternatives are Sesamo all information is represented ria. It is rigorous and simple from a selected, MCA methodology requires by an evaluation matrix, where KPIs, mathematical point of view, it gives defining the evaluation criteria that describing several aspects of the of- a complete ranking of the alternati- will allow assessing the performance fshore safety (as defined in section ves, and it does not suffer from rank of the different alternatives. Such 2) for upstream activities, are combi- reversal. The methodology requires criteria make the objectives qualita- ned to obtain a composite indicator the development of utility functions, tively and/or quantitatively measu- of the national safety performance expressing the relationship between rable. It can be useful to manage the in time. The computation in Sesamo an indicator value and the degree of criteria by a tree structure, making is addressed by a sequence of panels, goal attainment. Their definition re- apparent the relationships among the guiding the user through the MCA quires a long interaction between the various indicators and the final objec- steps (Figure 2). analyst and the competent authority tives and improving the logic of the The results can be rendered in Se- (see e.g. Maran & Garofalo, 2017). process. The score of each alternative samo by several kinds of diagrams and Nonetheless, the methodology makes is given by the combination of values charts. Among these, the so called the process transparent and traceable of its own indicators but because the dashboard view is the most peculiar and allows the stakeholders’ partici- indicators are expressed by their own one, having also the highest content pation, handling subjectivity intrin- specific measuring system, they must of information about the data and the sically present in all the phases of the be made comparable each other and performance, and allows the user to evaluation process. this is obtained applying utility fun- perform a simple sensitivity analysis, Summarising,the MCA was cho- ctions. Utility functions express the changing the weights assigned to the sen because, despite the difficulties satisfaction degree for an indicator, different specific objectives. that arise in defining/choosing value on a scale ranging from 0 (minimum functions and weights, this metho- satisfaction) to 1 (maximum sati- dology is conceptually simple, pro- sfaction); as such, they can be con- 3.2. Preliminary results duces a transparent and traceable sidered a form of data normalization process and allows the analyst to ma- but with a direct relation to the stra- In this prototype, semester data nage subjectivity in every step of the tegic vision of the public authority were used.The methodology was ap- process. and their objectives.The next step plied to data recorded since second consists in assigning weights to each semester 2014. indicator, in order to calculate the In Figure 3, the results were 3.1. “Classical” Multi Criteria Analysis and Sesamo tool

The MCA methodology was applied in order to obtain the prototype version of the composite indicator for the performance of offshore activities concerning hydrocarbon exploitation. MCA combines different evaluation criteria to get a final ranking of the alternatives. MCA consists of a series of well-defined steps that includes: a) the selection of the alternatives, b) the selection of evaluation criteria, c) the development of utility functions, d) the assignment Fig. 2. MCA steps and corresponding Sesamo panels. of weights to the objectives and e) Analisi multicriteria classica e relativi pannelli in Sesamo.

Dicembre 2017 135 environment shown, highlighting the different tors offers the opportunity for intro- elimination or drastic reduction of contribution to the composite indi- ducing further indicators in the futu- the hazards at source, is a key option cator of the three main criteria: KPI1 re. This will allow addressing other to pinpoint and reduce the offsho- (occupational safety), KPI2 (Navy critical issues related to the safety of re facility risks by appropriate KPIs and Coast Guard patrols monito- offshore O&G facilities in the next (Khan and Amyotte, 2002; Tugnoli ring), KPI3 (UNMIG inspections). steps of the “Indicator for Offshore et al., 2007; Crivellari et al., 2017). The chart shows the variation Safety” project, such as e.g. potential Table 1 shows an example of over time of the preliminary values for major accidents, role of mainte- inherent hazard KPI based on the of the composite indicator. In addi- nance in preserving the safety per- model simulation of the actual con- tion, the chart allows the decision formance and interactions with na- sequences stemming from the poten- maker to single out the most critical val and helicopter traffic. This will tial accidental scenarios possible for aspects. For instance, it is possible to provide an even more comprehensi- each unit of the offshore installation identify that in the second semester ve picture of the offshore safety per- (i.e. fire, explosion, toxic release) as 2014 the overall performance was formance. identified e.g. by the hazard report of lower than the others because of the According to the schematization the facility. For each target of con- poor performance of the criterion re- of accidents provided by the “Swiss cern, two KPIs are obtained: the po- lated to the KPI2. This, in turn, was Cheese” Model of safety (Reason, tential KPI is representative of the due to the beginning in 2014 of the 1990), new indicators may be defi- maximum damage area derived from collaboration on platform patrolling ned to monitor either the underlying the worst case accident scenario, among UNMIG, the Italian Navy hazards, or the performance of the while the inherent KPI is calculated and the Coast Guard and the fol- safety layers (e.g. IW, IPIN), or the by weighting the damage area with lowing start up phase. accidental outcomes (e.g. LTIF. the safety scores of the equipment FAR). As regard the underlying ha- unit, taking into account the credi- zards, past accidents have demon- bility of its release modes. Table 1 strated the potential of offshore shows an example of the results for 4. Possible expansion of the O&G activities for severe damages, a gas-water separator derived from indicator set multiple fatalities, direct and indi- the application of the method to an rect economic losses, environmen- offshore fixed platform producing The development of a flexible tal contamination (Christou and natural gas. tree-structured system composed by Konstantinidou, 2012). The inhe- multiple safety performance indica- rent safety approach, based on the 5. Conclusions

A novel quantitative methodology has been developed and tested to measure and monitor safety of offshore hydrocarbon exploitation activities. The method is based on the joint use of the tree of impacts and the multi-criteria analysis approach: the tree of impacts identifies the significant criteria and the related set of key indicators (KPIs) that cover specific aspects of safety in this industry; the multi-criteria analysis defines the KPIs combination procedures and calculates the composite indicator. Altogether, the indicator system tracks the time evolution of the global safety performances of the sector Fig. 3. Preliminary results of the computation of the safety composite indicator, using and the effects of the implemented the three criteria considered in this paper. safety actions. The methodology was Risultati preliminari del calcolo dell’indicatore composito della sicurezza sulla base dei tre tested by developing a preliminary criteri considerati. model with a minimum number of

136 Dicembre 2017 ambiente

Tab. 1 Example of potential and inherent KPIs addressing specific targets of major accidents calculated for a gas-water separator. Esempio di KPIs potenziali e inerenti indirizzanti specifici targets di incidenti rilevanti calcolati per un separatore gas-acqua. Equipment Release mode Reference Safety unit accident scores Humans Assets Assets Assets Environment scenario (1/y) (Process (Facility (Marine (Water equipment) structures) structures) column) Gas Small leak Ø 10 mm Jet fire 7.9 · -310 20.5 16.0 5.0 5.0 - Separator Medium leak Ø 50 mm VCE 1.5 · 10-3 85.5 78.0 35.5 50.5 - Catastrophic failure VCE 4.2 · 10-4 85.5 78.0 35.5 50.5 - Unit hazard potential KPI (m2) 2.3 · 10+4 1.9 · 10+4 3.9 · 10+3 8.0 · 10+3 0 Unit inherent KPI (m2/y) 5.4 · 10 4.3 · 10 8.1 1.6 · 10 0 criteria and key performance indica- RSE Report (available at www. Petroleum Safety Authority Norway, tors. The model has been structured rse-web.it, in Italian). 2016. Trends in Risk Level in the so that it can be easily expanded to Grasso, F., Maran, S., 2012. SESAMO Norwegian Petroleum Activity – take into account all the criteria that SHARE ver. 3.0 – User Manual, Summary Report – Trends 2015 are useful to get a complete picture Deliverable of the project SHARE – Norwegian Continental Shelf. Sta- of safety in upstream activities in the – Sustainable Hydropower in Alpi- vanger, Norway. Italian seas. The application of the ne Rivers Ecosystems. Reason, J., 1990. Human Error, Cam- methodology evidences the poten- HSE, 2015. Offshore Statistics & Regu- bridge University Press, New York, tial of the new technique and its ef- latory Activity Report 2015, Health USA. fectiveness both in pinpointing and and Safety Executive Report. Saaty, T.L., 1980. The Analytic Hierarchy summarizing the different contribu- IOGP, 2015. Safety performance indi- Process, McGraw Hill. tions to the overall safety profile of cators – 2015 data. The Interna- Saracino A., Antonioni, G., Spadoni, the offshore upstream system. tional Association of Oil&Gas Pro- G., Guglielmi, D., Dottori, E., Flami- ducers Report. gni, L., Malagoli, M., Pacini, V., 2015. Keeney, R.L., Raiffa, H., 1993. Decisions Quantitative assessment of occu- with multiple objectives-preferences pational safety and health. Safety References and value tradeoffs. Cambridge Science, 72(2015), 75-82. University Press, Cambridge & Tugnoli, A., Cozzani, V., Landucci, G., Christou, M., Konstantinidou, M., New York. 2007. A Consequence Based Ap- 2012. Safety of offshore oil and gas Khan, F.I., Amyotte, P.R., 2002. Inhe- proach to the Quantitative Asses- operations: Lessons from past acci- rent safety in offshore oil and gas sment of Inherent Safety. AIChE dent analysis. activities: A review of the present Journal, 53(12), 31713182. Crivellari, A., Tugnoli, A., Macini, P., & status and future directions. Journal Tugnoli, A., Santarelli, F., & Cozzani, V., Cozzani, V., 2017. Multi-Criteria of Loss Prevention in the Process In- 2008. An Approach to Quantitati- Indicators for the Inherent Safety dustries, 15(4), 279-289. ve Sustainability Assessment in the Profile of Off-Shore Oil&Gas Faci- Maran, S., Garofalo, E., 2017. INSPIRE- Early Stages of Process Design. En- lities, in Offshore Mediterranean Grid: Improved and enhanced sta- vironmental Science & Technology, Conference and Exhibition, 29-31 keholder participation in reinforce- 42(12), 4555-4562. March, Ravenna, Italy. ment of electricity grid, RSE, Milano UNI EN, 2007. UNI EN 7240 Stati- de Ville B., 2006. Decision Trees for Bu- (available at www.inspire-grid.eu). stics on occupational injuries. UNI siness Intelligence and Data Mining: OECD, 2008. Handbook on Construc- Ente Nazionale Italiano di Unifica- Using SAS® Enterprise Miner™. ting Composite Indicators, OECD zione, Via Sannio, 2 20137 Milano, Cary, NC: SAS Institute Inc., NC, (available at www.oecd.org). Italia. USA. Fülöp, J., 2005. Introduction to decision making methods. BDEI-3 wor- Acknowledgement kshop, Washington. 2005. The study was carried out as part of “Offshore Safety Indicators Project” in the Girardi, P., Maran, S., Stella, G., Beretta, framework of the Research Programme “Network for Offshore Safety”, funded by S., 2014. Metodologie e processi the Italian Ministry of Economic Development, Directorate-General for Safety of Min- per decisioni condivise su proget- ing and Energy Activities, National Mining Office for Hydrocarbons and Georesources ti di nuove infrastrutture di rete, (DGS-UNMIG), whose support is gratefully acknowledged

Dicembre 2017 137 occupational safety and health Tips on Occupational Safety and Health – OS&H

Mario Patrucco, Full Professor of Occupational Risk Assessment and Management at industrial and construction sites, Politecnico di Torino Luisa Maida, PhD, Metrology: measuring science and technique. Course curricula “Industrial safety and risk analysis” Paolo Fargione, PhD student, Management, Production and Design Course curricula OS&H

Due to the limited number of available pages for the OS&H topics fundamentals for the mining engineering students, and partly covered in this issue of GEAM, I decided to “lyophilize” my introduction to the OS&H aspects, further discussed in specific courses. following few lines: in the second semester of 2017 the work-related Of course, this knowledge is also precious in other NACE sectors, fatalities rates showed a concerning increase if compared to the con- from underground constructions to industrial activities where these tinuous decreasing trend of the last years. This unfortunately confirms systems and fittings are necessary. what we wrote in the very first issue of GEAM 147 (Patrucco et al., According to the good engineering practice and to the Law princi- 2016), when the OS&H topics were introduced. pia (e.g. the Framework European Directive 89/391 on the minimum A bird’s eye view of the data on the occupational diseases- even if requirements on OS&H conditions) the correct management of working obviously the assessment and compensations take time, and in many environments through Risk Assessment and Management to prevent cri- cases the induction period of exposure / consequence of the carcino- tical exposures at workplaces should be based on the following steps of

LE RUBRICHE DI GEAM gens can be measured in decades – seems to confirm a similar trend. Prevention: This being all for the general considerations, from here on I leave 1. Hazardous pollutants identification (both in routine and in exceptional room for the exposure, albeit abridged, of the results of a thorough situations, i.e. faults, emergency conditions) and -if technically feasible study carried out by PhD Luisa Maida and PhD student Paolo Fargio- – zeroing, e.g. by exclusion from the production cycle; ne about the progress in industrial ventilation, a topic I’ve been wor- 2. Workers’ exposure assessment through representative measurement king on since the days of my Mining Engineering graduation studies. campaigns (Bisio et al., 2016, 2017); The mining sector, in particular the underground mining activities, 3. Control design, hierarchically considered (Maida et al., 2015) in terms requires devoted knowledge and technical developments due to its of: serious OS&H criticalities and the related need of special fittings, in 3.1 Control of pollutant emission from the sources previously iden- particular to ensure healthy conditions of the working environments tified: some technical improvements are often possible, and the and to reduce the pollution caused by both natural (formation) cau- maintenance conditions of sources are strictly linked to their pol- ses, and the mining activities. The Mine Plants (power, systems and lutant emission (e.g. poor maintenance of a working equipment fittings) Course was, at the time, not by chance included among the contributes to environmental noise, airborne dust, etc.);

Dato lo spazio limitato di questo numero di GEAM per le tematiche di OS&H, ho pensato preferibile limitare a poche righe queste mie considerazioni richiamando le recenti variazioni – di nuovo in aumento – nel trend infortunistico e presumibilmente in futuro anche nel trend delle malattie professionali che presentano maggiori isteresi, per lasciare spazio e le purtroppo prevedibile le variazioni nel trend delle malattie professionali per lasciare spazio: ad una sintesi, dei risultati di uno studio curato da PhD Luisa Maida e PhD Student Paolo Fargione sulla evoluzione dei sistemi di ventilazione industriali, una tematica che mi ha visto impegnato sin dai remoti tempi dei miei studi in ingegneria mineraria. Come è ovvio il comparto minerario, e segnatamente le attività estrattive in sotterraneo, a causa delle evidentissime criticità in materia di OS&H, e della necessità di gestirle in gran parte attraverso impiantistica dedicata, ha costituito da sempre palestra di studio ed approfondimento essenziali. Ciò vale in particolare per la garanzia di vivibilità degli ambienti di lavoro, fisiologicamente oggetto di inquinamento da parte sia di inquinati di formazione, sia di inquinanti generati nel corso delle operazioni di coltivazione (non a caso la materia Impianti Minerari figurava fra le fondamentali nel corso di studi, e trattava parte degli aspetti di OS&H, integrati poi in corsi specifici). Ovviamente queste conoscenze trovano utile applicazione anche in altri comparti, dalle attività cantieristiche in sotterraneo a tutte le altre lavorazioni industriali in cui tali impianti risultano necessari.

138 Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 138-142 occupational safety and health

3.2 Control of the pollutant dispersion into the working environment: ronment through pollutant dilution and air substitutions is a last resort, pollutant’s capture in the proximity of the source, avoiding/limiting expensive and somehow unreliable, since unacceptable pollutant concen- the dispersion in the environment; trations may remain in some areas outside the clean air stream. 3.3 Environmental pollution management (pollutant dilution and air The definition of the required capture capability clearly depends on substitutions): action on the shop environment. the pollutant emission characteristics, but, since obviously the emission Both points 3.2 and 3.3 involve, in the case of airborne pollutants as of pollutants from a process is an unwanted by-product, the direct me- dusts, gases, etc., the introduction of ventilation systems. asurement of emission rate and characteristics with the desired detail is Moreover, if such systems are used to control the pollutant’s emission in many cases very difficult or even impossible. The same criticality rises from machines or connected production lines, this implies that the ven- in attempts to evaluate emitted quantities of pollutants through mea- tilation system should be included in the machine or plant EC marking surements of differences in mass or energy. Finally, in many cases the process: in accordance with 2006/42/EC Directive (art. 2 letter a) the 4th computation based on the physical or chemical characteristics of the ma- indent states that “assemblies of machinery referred to in the 1st, 2nd terials-substances involved in the process (e.g. vapor tension in different and 3th indents or partly completed machinery referred to in point (g) temperature and pressure conditions) is often vain, due to the lack or poor which, in order to achieve the same end, are arranged and controlled so quality of the input data available in literature. that they function as an integral whole”. Some experimental research work, carried out care of the Occupa- Important progress is continuing for the ventilation systems, both in tional Safety laboratory of Politecnico di Torino, led to the following results techniques and technologies, and in computerized fluid motion models, in (Cigna et al., 2006): the simplified assumption that the air is an incompressible fluid answe- 1. the direct plotting of emission profiles of gas/vapor from hot emit- ring to the Darcy’s equation, or in approaches based on Computational ting sources in presence of lateral hoods (see Fig. 1). The test results, Fluid Dynamics – CFD (Borchiellini et al., 2009). collected by means of a thermal video camera, show the different Only proper design of the system, installation, operation conditions and temperature values of objects in the “field of view” of the camera: we maintenance ensure the performance requirements, i.e. effectiveness in can then directly appreciate the efficiency of the capturing system. The the control of workers’ exposures. This involves feedback self-regulation, approach is clearly suitable only in case of hot pollutant emissions, thorough monitoring and alarm systems essential to support the schedu- and a specific frame is necessary to identify the isothermal profiles. led maintenance program with timely on demand corrective maintenance 2. experimental data collection and set up of computer models for the interventions. simulation of the behavior of airborne pollutants (dusts, gases and Provided that the basic target of the work environment management vapors) (see Tab. 1). is the minimization of the workers’ exposure, a correct approach should Concluding, the design of ventilation systems suitable for an effective be based on a systematic monitoring of the results of pollutant concentra- management of airborne particulates, gases and vapors in work envi- tions measurements from personal samplings, possibly implemented with ronments involves the definition of critical input parameters, and this is a Biological Exposure assessment (both on a statistically significant basis). very demanding, or even impossible, task. Because of organization and economic reasons, these techniques cannot The solution is often an empirical approach based on the lessons be considered for every-day use, and a practical indirect approach can be available from a number of case histories. The American Conference of based on the monitoring of the efficiency of the pollutants management Governmental Industrial Hygienists - ACGIH -since the beginning of ‘50 systems. provides suggestions in the Industrial Ventilation -a Manual of Recommen- With reference to points 3.2. and 3.3., it is worth remembering that ded Practice for Design. Starting from a rigorous discussion on the basics the most critical input parameter in the design of suction type – open of the design of ventilation systems, the Manual discusses the possible hood- systems, conceived for the capture of pollutants in the proximity practical approaches to a large number of industrial scenarios, and sug- of the source, is the actual capture capability. Acting on the shop envi- gests empirical input data drawn from a large data collection, mainly in

Fig. 1. Left: isothermal profiles; right: resulting assessment of the capture efficiency of the system (4 side lateral hood): top/down show satisfying/unsatisfying situations.

Dicembre 2017 139 occupational safety and health

Tab. 1. Example of the results of: modeling the trajectories and capture chances for airborne particulates in presence of a lateral hood – LH (left), and of laboratory data collecting by means of tracer gas in a 60 × 70 cm plating bath (4 side lateral hoods) scale model , and 3D plotting of the maximum extent of the capture surface (right).

30 µm dia., 2.4 t/m3 particles, lateral hood LH intake flow = 0.021 3m /s; X = width of bath X = horizontal distance from LH; Y = length of bath Y = particles vertical distance from the floor Z = distance from the tank surface where the hood influence is still observed the form of expectable pollutants emission rates from different sources, 4. the decision making and resulting system restoration; and typical layout schemes and capture velocities for an effective control. 5. the validation of the result (e.g. restored air velocities, etc., and pollu- Such suggestions are very helpful in the project approach, making tant concentrations at the workplaces / workers’ exposure). directly possible a sizing technically compatible with standard ranges of ACGIH strongly encourages the interchange of experiences among adjustment (e.g. in flowrate and pressure head of different branches): it people trained in Industrial Hygiene, and OS&H experts in general: becomes then possible to ensure the needed performance, that can be Journal of Occupational and Environmental Hygiene - JOEH, professional defined in detail only after the system installation, on the basis of the courses, webinars, workshops, and symposia, as well as a vast list of tech- results of measurement of the workers’ exposure conditions. nical and scientific signature publications (including the TLV®/BEI® publi- Therefore, the control of workers’ exposure to work-related pollutants cations and related documentation), provide scientific information sharing should involve and address the whole lifecycle of the ventilation system, to members and experts in the OS&H field(1). from the very early steps of design to operating conditions and mainte- Paolo Fargione and Luisa Madia recently attended to the course on nance. This implies the identification and the continuous monitoring of “Fundamental in Industrial Ventilation: practical use of useful equations” the minimum requirements to ensure the system’s efficiency in terms of held in Cincinnati from 18 to 22 September 2017. They noted important workers’ exposure control according to up to date OS&H standards, both differences in the ACGIH approach, if compared to what they learned du- technical and epidemiological (Patrucco et al., 1996). ring their university studies in Italy. From the course coordinator’ introduc- For a more detailed information on the peculiar topics concerning the tion speech: “the application of the principles of ventilation to solve pro- test of existing systems, operation and efficiency control along the time, blems of workers’ exposure to pollutants or general hygiene problems of troubleshooting, etc., ACGIH in 2007 published a special volume for venti- a plant implies a process of technical solutions to two types of problems: lation systems’ maintenance and operation (ACGIH, 2007). air and pollutants. Generally, these problems relate to fluid movements In particular, the Manual discusses, on the basis of analyses on real (mass) as energy transfer calculations. Considering the complex formulas, cases, the techniques to diagnose the problems that may cause degraded we need to simplify the process and exploit simple things at the basis performances, and the approaches to identify the best solutions to restore of advanced mathematical and physical models: the principle of mass the system to the design specifications. and energy conservation. All industrial ventilation problems are resolved The ventilation system’s performance can in fact decrease due to a in this way”. Basically, the course organization was set to provide a “back large variety of circumstances, and, in the experience of the Authors, such to basics” technical and practical guidance on the essential aspects of decrease can remain undetected if only noise, air movement in proximity design and maintenance of ventilation systems, specifically conceived for of the hoods and static pressure at the hoods are loosely evaluated, with professionals working in the OS&H field. serious decay of the enviromental conditions at workplaces. Moreover, the word “simplification” was used in its real meaning: to To diagnose and solve ventilation system problems we shall consider make easier and facilitate something. This might be a truism, except that the whole system, and understand how all the system’s components fit unfortunately, in the Authors experience, “simplification” is often syno- together. As an example, troubleshooting should cover: nymous with “omitting”, and leaving room in complex scenarios to a num- 1. the problem definition (talking with workers and maintenance staff, ber of omitted or underestimated hazard factors causes ineffective Risk identifying mechanical problems, collecting documents, etc.); Assessment and Management, and consequences in terms of accidents 2. the system walkthrough looking for obvious problems, system technical and health impairments, (Borchiellini et al., 2017). modifications, …, in a Safety Review approach (Centre for Chemical In a correct approach, simplifying the analysis of a system does not Process Safety of the American Institute of Chemical Engineers, 2008); 3. the measurements and critical evaluation of the results (e.g. air veloci- 1 According to the 2017 Member Directory, 20 people compose the ty in the duct, hood and branch static pressure, …); small qualified Italian community.

140 Dicembre 2017 occupational safety and health entitle to assume that the system is simple: in the field of industrial venti- matic approach to address and solve complex problems, starting with the lation, once the technical and operational design specifications of a plant fundamental principles. are defined, the biggest challenge is to maintain efficiency over time and So, “the only way to figure out if everything works properly is to mo- performance in all “reasonably foreseeable” operational and fault sce- nitor the ventilation system: tomorrow static and flow pressure measu- narios, as well as under emergency conditions. Not least in the case of rements will become your routine”. At that very moment, a sliding wall possible changes in production processes and / or in the use of new ma- opened, unveiling the pilot ventilation system for the practical exercises terials, or even in the particular case of use or handling of carcinogens (Fig. 2a&b, and Table 2). for epidemiological or industrial toxicology studies that may affect the An important contribution to the real effectiveness of the course re- exposure conditions of workers. Therefore, simplification implies a syste- sults from the different cultural backgrounds (engineers, industrial hygie-

Fig 2a. Pilot ventilation system. Fig 2b. Driven practical measurements.

Tab. 2. Practical examples of direct measurement results.

Measurement instrument setup and measurement points on Trends of flow rate in different ventilation system operating conditions (as discussed in Patrucco trasversal section of the duct and Savoca, 1999).

Sketch of the final segment of the analyzed ventilation system. System’s efficiency monitoring

Dicembre 2017 141 occupational safety and health nists, chemists) of the attendees, sharing knowledge and skills in a Pro- 1330 Kemper Meadow Drive, Cincinnati, Ohio, USA, ISBN: 978- blem Based Learning – PBL approach. This approach makes possible a 1-882417-66-7. practical and immediate feedback on the analyzed topics, and a familia- Bisio, P., Fargione, P., Maida, L., 2016. The measuring processes and rity with the measuring techniques and instruments. equipment setup in System Quality and Occupational Safety & He- So, it is possible to simulate possible operational scenarios to: alth Risk Assessment” GEAM, geoingegneria ambientale e minera- − identify (but first to notice!) the most common system-related devia- ria, Anno LIII, n. 2, Agosto 2016, pp. 23-32, ISSN 1121-9041. tions or components faults, based on simple measurements; Bisio, P., Fargione, P., Maida, L., 2017. Representativeness of the measu- − properly assess the causes that may affect the system performances; rements results: a key issue for Occupational Risk Assessment and − select the most appropriate countermeasures to restore the system Management. Discussion on air dispersed particulates GEAM, ge- efficiency. oingegneria ambientale e mineraria, Anno LIV, n. 1, aprile 2017, pp. On the basis of the experience gained attending the training 37-46, ISSN 1121-9041. course organized by ACGIH on the design and management of Borchiellini, R., Carvel, R., Colella, F., Rein, G., Torero, J.L., Verda, V., 2009. industrial ventilation systems, we can draw the following conside- Calculation and design of tunnel ventilation System using a two scale rations: modelling approach, Building and environment, Vol. 44, Issue 12, El- 1. the pragmatic approach adopted by ACGIH actually makes sevier, pp. 2357-2367. possible to set up and manage industrial ventilation systems Borchiellini, R., Cirio, C., De Cillis, E., Fargione, P., Maida, L., Patrucco, M., having a clear idea of the purpose for which they are designed 2017. Criticalities on Highway Maintenance Yards: Some Suggestions and implemented, namely to ensure adequate environmental to Improve the Effectiveness of OS&H Supervision/Inspection Activi- conditions for the workers. This might well complement what in ties, Chemical Engineering Transactions Vol. 57, 2017, pp. 397-402, WOSNET 17 (De Cillis et al., 2017); DOI: 10.3303/CET1757067, ISSN 2283-9216. 2. the PBL technique, applied to the pilot plant, makes possible for the Centre for Chemical Process Safety of the American Institute of Che- students to become aware of the practical problems of managing and mical Engineers, 2008. Guidelines for hazard evaluation procedures, verifying the efficiency of a ventilation plant, and, thanks to the orga- second edition with worked example ISBN 978-0-471-97815-2. nization in working groups, to exploit the synergies of their different Cigna, C., Francese, S., Patrucco, M., 2006. An analytical approach to the cultural background. A common theoretical lesson can hardly achieve lateral open hood based dust exhaust systems design and efficiency these goals. evaluation” VENT 2006 Poster session, May 13 - 16 2006, Chicago We can here conclude that ACGIH made available a practical and ef- IL USA. fective approach to the design and management of industrial ventilation De Cillis, E., Maida, L., Fargione, P., Patrucco, M., 2017. An experience systems. Having constantly in mind the goal of the systems, i.e. the of University Education on OS&H at Politecnico of Turin, WOS NET safety of workers, certainly motivates designers, apprentices and 2017, October 3-6 2017, Book of proceedings pp. 283 - 289 ISBN students much more than a technical training focused exclusively on 978-1-138-03796-0 /978-1-135-17757-1. the system characteristics. Faina, L., Patrucco, M., Savoca, D.,1996. La valutazione dei rischi ed il Last, but not least, the Authors confirm, on the basis of personal expe- documento di sicurezza e salute nelle attività estrattive a cielo aperto, rience, that the ACGIH’s approach to the continuous training of industrial European Commission S.H.C.M.O.E.I. – Workshop on Risk Asses- ventilation systems technicians is really effective also thanks to the PBL sment, Gubbio, 20-23 giugno 1996. technique applied to real cases, and can rightfully be considered a Labagnara, D., Maida, L., Patrucco, M., 2016. “Tips on Occupational Safety good example of dissemination of the Culture of Safety. and Health – OS&H”, GEAM, geoingegneria ambientale e mineraria, Anno LIII, vol. 16, n. 1, Aprile 2016, pp. 58-60, ISSN 1121-9041. Labagnara, D., Maida, L., Patrucco, M., 2015. Firedamp Explosion during References Tunneling Operations: Suggestions for a Prevention Through Design Ap- proach from Case Histories, pp. 2077-2082 – Chemical Engineering American Conference of Governmental Industrial Hygienists, website: Transactions vol. 43 2015, ISBN 978-88-95608-34-1, ISSN: 2283- http://www.acgih.org 9216, DOI: 10.3303/CET1543360 AIDIC – The Italian Association Industrial Ventilation: A Manual of Recommended Practice for Design, of Chemical Engineering. 29th Edition, 2016, ACGIH, Kemper Woods Center 1330 Kemper Patrucco, M., Savoca, D., 1999. Attuazione e conservazione della sicu- Meadow Drive, Cincinnati, Ohio, USA, ISBN: 978-1-607260-87-5. rezza nell’ambito della normativa vigente, Convegno “Le tecnologie Industrial Ventilation: A Manual of Recommended Practice for Ope- dei materiali lapidei alla sfida del nuovo millennio”, Università di ration and Maintenance, 2007, ACGIH, Kemper Woods Center Cassino, 23-24 Settembre 1999.

142 Dicembre 2017 diati news Ingegneria del petrolio e mineraria al Politecnico di Torino Petroleum and Mining Engineering at Politecnico di Torino

Cari colleghi,

considerando il focus di questo numero della Rivista, la rubrica DIATI NEWS offre in questa occasione un approfondimento sull’offerta formativa del Politecnico di Torino, in particolare sul corso di laurea magistrale in Petroleum Engineering che già da anni è un punto di riferimento per il settore nel panorama internazionale e che dall’anno accademico 2017/2018 si è ampliato, offrendo un nuovo percorso in Mining Engineering, unico in Italia. Con l’augurio di una buona lettura Vi porgo i miei più cordiali saluti Il Direttore Prof. Rajandrea Sethi

Il corso di laurea magistrale in Ingegneria collaborazione con Eni e con Eni Corporate University e accoglie del Petrolio circa 40 studenti all’anno. The Master of Science in Petroleum Engineering Il nuovo orientamento in Ingegneria LE RUBRICHE DI GEAM mineraria Il Politecnico di Torino ha da sempre avuto una forte Scuola The new specialization in Mining Mineraria di riconosciuto prestigio a livello nazionale ed internazionale. Da questa, nel 1959, nasce anche la specializzazione in Engineering Ingegneria del Petrolio, che inizialmente comprendeva i soli corsi fondamentali del settore (geologia, ingegneria dei giacimenti, Da quest’anno il corso di laurea ha cambiato nome in “Petro- perforazione e completamento dei pozzi petroliferi, tecnologie leum and Mining Engineering”, prevedendo l’affiancamento di un di produzione), ai quali successivamente si sono affiancate altre percorso “Mining Engineering”. Il corso di laurea si è, quindi, com- materie di base e specialistiche (geofisica, meccanica dei fluidi nei pletato, abbracciando l’intero settore della estrazione e produzio- mezzi porosi, geomeccanica, HSE, etc.). ne di risorse fluide e solide dal sottosuolo. Questa estensione del Dall’anno accademico 2010/11 il percorso in Ingegneria del corso di laurea al settore minerario è avvenuta in modo naturale, Petrolio, completamente tenuto in lingua inglese già dal 2008 e grazie al fatto che i due settori (minerario e petrolifero) poggiano incardinato nell’offerta formativa del Dipartimento di Ingegneria le proprie basi scientifiche e culturali nelle stesse discipline scien- dell’Ambiente, del Territorio e delle Infrastrutture, è si è trasfor- tifiche e ingegneristiche ed hanno molti ambiti comuni nelle tec- mato nel corso di laurea magistrale in Petroleum Engineering. Tale niche e modalità di: indagine e caratterizzazione del sottosuolo, corso di laurea ha avuto da subito una connotazione fortemente ottimizzazione delle risorse a disposizione, rispetto dei principi internazionale, essendo frequentato da studenti provenienti da di sicurezza e della tutela dell’ambiente durante le operazioni di tutto il mondo. Inoltre ha avuto un distintivo tratto professiona- estrazione delle risorse dal sottosuolo. lizzante per l’intenso rapporto con l’industria che consente di L’orientamento in “Mining Engineering”, unico nel panorama proporre esercitazioni svolte secondo le modalità e con gli stru- italiano così come l’orientamento in “Petroleum Engineering”, ha a menti tipici delle industrie del settore, seminari specialistici con sua volta una vocazione internazionale e uno stretto legame con l’intervento di tecnici esterni all’Università, sia italiani che stranieri, l’industria mineraria italiana e internazionale. D’altro canto, l’Inge- e visite di istruzione ad impianti e cantieri, tesi e tirocini in azienda. gneria mineraria al Politecnico di Torino vanta una lunga tradizione Al percorso di laurea segue anche un programma di Master che risale agli inizi del ‘900. La riattivazione del percorso, dopo la di secondo livello in “Petroleum Engineering and Operations”, sua interruzione a inizio anni ‘90, è dettata anche dalla profonda anch’esso offerto interamente in lingua inglese. Il master, giunto trasformazione del settore, che oggi vede tra le sfide principali il alla sua quindicesima edizione, è offerto dal Politecnico di Torino in bisogno di estrarre materie prime in modo sostenibile e rispetto-

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017, 143-144 143 diati news so dell’ambiente. In questo, le competenze del Dipartimento di sono costituiti dalle figure dell’ingegnere prospettore e progettista Ingegneria dell’Ambiente, del Territorio e delle Infrastrutture e del delle miniere e del direttore dei lavori minerari che collabora alla suo corpo docente possono dare un contributo rilevante. gestione, o è responsabile, della produzione della miniera e degli impianti di trattamento in superficie. Le figure professionali Occupational profiles Studenti internazionali International students

Le figure professionali che il nuovo corso di laurea intende formare, in linea con quanto prefissato nel precedente percorso Negli ultimi 3 anni nel corso di laurea in Petroleum Engineering in “Petroleum Engineering”, sono ingegneri in grado di operare si sono laureati più di 150 studenti, la maggior parte di prove- proficuamente e fin da subito nel settore petrolifero e minerario, nienza internazionale, in particolare il 50% circa proveniente da che si contraddistingue per l’elevato livello tecnico e tecnologico, Medio-Oriente e continente asiatico e il 30% circa dall’Africa. Sto- per l’interdisciplinarietà e per la dimensione internazionale che ricamente la provenienza degli studenti è però molto diversificata impone agli specialisti di essere in grado di operare in contesti e annovera studenti provenienti da oltre 50 Paesi diversi. socio-ambientali molto diversi e ad affinare le proprie capacità di L’indirizzo in Petroleum Engineering vede già da anni un’im- relazione e di comunicazione. portante collaborazione con Eni Upstream ed Eni Corporate Tra le principali figure formate dall’indirizzo in ingegneria del University che, attraverso l’ENI project, offrono borse di studio e petrolio troviamo l’ingegnere di giacimento, che collabora alla rea- supporto ad alcuni studenti internazionali selezionati che seguono lizzazione, o è responsabile, di studi integrati di giacimento e l’inge- il percorso. Parallelamente il corso di studio si sta muovendo per gnere di perforazione, che segue la stesura e/o la realizzazione del stabilire contatti con il mondo dell’industria mineraria e rendere programma di perforazione e completamento dei pozzi petrolife- disponibili borse di studio anche per gli studenti del nuovo per- ri; a valle del percorso in ingegneria mineraria i principali sbocchi corso in Mining Engineering.

Maggiori informazioni Further information

Per maggiori informazioni sul corso di studi è possibile consultare la pagina del portale dedicata: https://didattica.polito.it/laurea_magistrale/petroleum_and_mining_engineering/it/presentazione o scrivere a: [email protected]

144 Dicembre 2017 atti dell’associazione L’Associazione Georisorse e Ambiente ha lo scopo istitu- Oltre agli Atti dell’Associazione, pubblica memorie, co- zionale di realizzare – attraverso svariate iniziative culturali, ed municazioni scientifiche e note di Soci o anche di Studiosi eventuali studi e ricerche – collegamenti tra Persone ed Enti che non associati: la pubblicazione di memorie, comunicazioni svolgono la loro attività nell’ambito minerario ed in campi affini o scientifiche e note è comunque subordinata al parere favore- si occupano delle scienze ad essi attinenti. vole del Comitato Scientifico della rivista. Gli appartenenti all’Associazione si dividono in Soci Onorari, Le idee espresse dagli Autori non impegnano né la ri- Sostenitori, Ordinari-collettivi, Ordinari-individuali e Juniores. I vista né l’Associazione. GEAM si riserva tuttavia il diritto Soci Onorari sono nominati a seguito di referendum. Per essere di non accettare quegli articoli che non appaiono consoni ammesso a Socio (Sostenitore, Ordinario o Junior) è necessa- al suo carattere o ai fini dell’Associazione. La riproduzione rio rivolgere domanda scritta, corredata, di norma, dalla firma degli articoli è consentita dietro permesso degli Autori ed a di presentazione di due Soci Ordinari. I Soci contribuiscono con condizione che sia citata la fonte. Si accettano e sono graditi una quota annuale alle spese di gestione dell’Associazione. L’am- scambi con riviste e pubblicazioni analoghe. montare della quota è fissato annualmente dal Consiglio Direttivo (vedi tabella seguente). Consiglio Direttivo dell’Associazione (Quadriennio 2016-2019) QUOTE ASSOCIATIVE 2017 - GEAM Presidente Pietro Jarre 1° anno di iscrizione 50% della quota (non ripetibile) Vice Presidente Anna Maria Ferrero TIPO DI SOCIO Quota annua Vice Presidente Francesco Luda di Cortemiglia Ordinario Individuale - da diritto al solo Socio ad iscriver- e Segretario Generale (membro cooptato) si a quota ridotta a corsi e/o convegni + Rivista GEAM € 100 Ordinario Individuale con anzianità anagrafica superiore Consiglieri Stefano Airoldi a 75 anni - da diritto al solo Socio ad iscriversi a quota € 25 (rappr. Minova Carbotech GmbH) ridotta a corsi e/o convegni + Rivista GEAM Marilena Cardu (rappr. Diati – Politecnico di Torino) Ordinario Collettivo - da diritto a 3 persone ad iscriversi a 200 quota ridotta a corsi e/o convegni + Rivista GEAM € Alessandro D’amato Sostenitore Individuale - da diritto al solo Socio ad iscri- Davide Damosso versi a quota ridotta corsi e/o convegni + Rivista GEAM € 340 Jean Pierre Davit (rappr. Golder Associates S.r.l) Sostenitore Collettivo - da diritto a 6 persone ad iscriversi € 450 a quota ridotta a corsi e/o convegni + 2 Riviste GEAM Domenico De Luca LE RUBRICHE DI GEAM (rappr. Dst – Università di Torino) Junior (Studente o Dottorando) – da diritto al solo Socio ad iscriversi a quota ridotta a corsi e/o Convegni + Rivista € 25 Attilio Eusebio (rappr. Geodata S.p.A.) GEAM Massimo Ferrari (rappr. Citiemme s.r.l.) Costanzo Graffi I soci residenti all’estero dovranno corrispondere un contributo (rappr. Sws Engineering S.p.A.) addizionale per le spese postali di € 13. Pompeo Levanto (rappr. Basf. S.p.A.) – bollettino postale premarcato su richiesta Claudio Mattalia (rappr. Enviars s.r.l) – Bonifico Bancario a favore di Associazione Georisorse e Claudio scavia Ambiente (rappr. Diseg – Politecnico di Torino) IBAN: IT 23 U 02008 01160 000004478626 Marco Vicari BIC SWIFT: UNCRITB1AG0 (rappr. Officine Maccaferri S.p.A.) – Contanti o Assegno presso la nostra Associazione Revisori dei conti Giovanni Badino L’Associazione cura la pubblicazione di GEAM, periodico Enrica Michelotti tecnico scientifico su cui compaiono gli Atti dell’Associazio- Massimo Settis ne, inviato gratuitamente ai Soci.

Per scambi, come per ogni altra comunicazione, indirizzare a: Associazione Georisorse e Ambiente Albo dei Presidenti presso Prof. Lelio Stragiotti 1964-1990 (dal 1991 al DIATI – Dip. di Ingegneria dell’Ambiente, del Territorio e 1999 Presidente Onorario) delle Infrastrutture – Politecnico di Torino Prof. Sebastiano Pelizza 1991-1993 Corso Duca degli Abruzzi, 24 – 10129 Torino Prof. Renato Mancini 1994-1996 Tel. 011/0907681 – Fax 011/0907689 Prof. Gian Paolo Giani 1997-2002 e mail:[email protected] Ing. Francesco Luda di Cortemiglia 2003-2008 www.geam.org Prof. Gian Paolo Giani 2009-2015

Geoingegneria Ambientale e Mineraria, Anno LIV, n. 3, dicembre 2017 145 norme per la redazione di articoli per la rivista

Norme per la redazione di articoli per la rivista Geoingegneria Ambientale e Mineraria

Aspetti Generali Struttura dell’articolo

La collaborazione alla rivista “Geoingegneria Ambientale e Suddivisione – numerazione dei paragrafi Mineraria” è aperta ai soci e non soci dell’Associazione Georisorse Il testo deve essere diviso in sezioni chiaramente definite e nu- e Ambiente. merate in modo progressivo. La pubblicazione di memorie, comunicazioni scientifiche e I paragrafi devono essere numerati 1.1 (poi 1.1.1, 1.1.2,), 1.2, note tecniche subordinata al parere favorevole di almeno due refe- ecc. (l’abstract non deve essere incluso nella numerazione). Si deve ree scelti tra i membri del Comitato Scientifico della rivista. usare questa numerazione anche per i riferimenti all’interno del te- Le note tecniche, che sono usualmente più brevi di una memo- sto. Ogni paragrafo deve avere un breve titolo. ria, devono essere configurate per illustrare casi applicativi, progetti o innovazioni tecnologiche di interesse per i lettori. Informazioni essenziali Le idee espresse dagli Autori non impegnano né la rivista né Il testo deve essere preceduto da una pagina iniziale che con- l’Associazione. L’Associazione si riserva tuttavia il diritto di non tenga le seguenti informazioni. accettare quegli articoli che non appaiono consoni ai propri fini statutari. Titolo La riproduzione degli articoli è consentita dietro permesso degli Deve essere conciso e chiaramente riferibile agli argomenti Autori ed a condizione che sia citata la fonte. trattati dal lavoro. Deve essere redatto in tre lingue: Italiano, In- I testi, che possono essere proposti in Italiano, Inglese e Fran- glese e Francese. cese, devono essere inviati in via informatica al Direttore della rivista. Nomi degli autori ed enti di appartenenza I testi accettati per la pubblicazione dopo la fase di “review” Per ogni autore deve essere indicato l’ente di appartenenza con vengono inseriti nel primo fascicolo della rivista in cui si abbia di- l’indirizzo completo e l’e-mail di riferimento. sponibilità di spazio, nell’ordine conseguente alla data in cui sono pervenuti. Qualora l’autore sia un Socio dell’Associazione al lavoro Corresponding author verrà data priorità in relazione alla tempistica di pubblicazione. Deve essere chiaramente indicato a chi deve essere indirizzata Norme grafiche per la preparazione del manoscritto la corrispondenza in tutte le fasi del processo editoriale. I testi devono essere preparati e salvati con un editor di testo di Riassunto uso comune e inviati in via informatica alla redazione della rivista Il lavoro deve essere preceduto da un riassunto conciso e pre- ([email protected]) indirizzati al Direttore della rivista. ciso, che deve indicare in modo chiaro gli obiettivi della ricerca, Le figure e tabelle devono essere inserite al termine del testo i risultati principali conseguiti, le conclusioni più rilevanti, e deve precedute dall’elenco delle didascalie corrispondenti. poter essere presentato separatamente dall’articolo. Nel riassunto L’estensione complessiva dei lavori non dovrà eccedere, di nor- si devono evitare riferimenti bibliografici. Il riassunto deve essere ma, le sei pagine a stampa comprensive delle figure e delle tabelle, redatto in tre lingue: Italiano, Inglese e Francese. si consiglia quindi che il testo senza figure non ecceda le 42.000 battute complessive per lavori senza figure oppure le 28.000 battute Parole chiave se l’articolo comprende due pagine di figure. Per lavori di particola- Immediatamente dopo ciascun testo del riassunto redatto nelle re interesse scientifico e/o tecnico è facoltà del Direttore ammette- tre lingue di riferimento devono essere indicate non meno di cin- re anche lavori di lunghezza maggiore. que parole chiave. La pubblicazione sulla rivista “Geoingegneria Ambientale e Mineraria” è di norma in bianco e nero. Se si rende necessaria la Abbreviazioni quadricromia, gli Autori lo segnaleranno al momento della presen- Le abbreviazioni effettuate in modo diverso dallo standard del tazione al Direttore; l’Editore formulerà quindi un preventivo che settore trattato devono essere riportate in un elenco al termine del verrà trasmesso all’Autore. lavoro e ne deve essere chiarito il significato.

146 Dicembre 2017 norme per la redazione di articoli per la rivista

Ringraziamenti – Risultati non pubblicati e comunicazioni personali non devono, per quanto possibile, essere indicati nella bibliografia, ma I ringraziamenti devono essere riportati al termine del lavoro, solo citati nel testo. prima della Bibliografia. Nei ringraziamenti devono essere indicati – L’indicazione “in press” di un articolo implica che questo è già coloro che, a vario titolo, hanno fornito assistenza durante la ricer- stato accettato per la pubblicazione. ca nonchè gli enti finanziatori. Citazioni web Unità di misura Si deve fornire l’URL completo di riferimento e la data alla Le unità di misura devono essere quelle del Sistema Interna- quale si è fatto accesso al sito con la dicitura (“accesso in data xx/ zionale (SI). xx/xxxx”). Ogni ulteriore informazione, se conosciuta, deve essere fornita (DOI, nome dell’autore, data, ecc.). Figure e grafici Le citazioni web devono essere riportate in una lista separata al – usare sempre gli stessi caratteri (possibilmente: arial, courier, termine dei riferimenti bibliografici. times, symbol) e le stesse dimensioni delle scritte; – numerare le illustrazioni secondo la sequenza con la quale ap- Stile delle citazioni bibliografiche paiono nel testo; Tutte le pubblicazioni citate nel testo devono essere presentate – riportare le didascalie delle figure e tabelle in una pagina a parte; in una lista in ordine alfabetico al termine del manoscritto. – fornire le immagini per quanto possibile delle dimensioni Nel testo le citazioni vanno redatte come segue: dell’immagine da riprodurre sul lavoro. Fare in modo che que- – Autore singolo: il cognome dell’Autore (senza le iniziali del ste corrispondano alle dimensioni di una, due o tre colonne nome di battesimo a meno che non ci siano ambiguità) e della rivista a stampa; anno di pubblicazione; – fornire le figure separatamente, sia all’interno del testo che – due Autori: entrambi i cognomi degli Autori e l’anno di pub- come files; blicazione; – gli autori sono pregati inoltre di tenere conto della riprodu- – tre o più Autori: il cognome del primo Autore seguito da et al. cibilità delle figure in termini di dimensioni del tratto e delle e l’anno di pubblicazione. caratteristiche grafiche delle figure. Le citazioni nel testo possono essere fatte direttamente o tra – Gli autori devono disporre dei copy-rights delle figure even- parentesi. tualmente riprese da altri documenti. Quando c’è una lista di citazioni, queste devono essere elencate facendo riferimento all’anno di pubblicazione. Illustrazioni a colori Esempi: La rivista è stampata prevalentemente in bianco e nero. Per 1) “Come dimostrato (Autore 1, 1999a,1999b, 2000; Autore 1 e le illustrazioni a colori l’Editore contatterà l’Autore in merito ai Autore 2, 2001)”. relativi maggiori costi di stampa che saranno a carico dell’autore. 2) “Come recentemente discusso da Autore 1 et al. (2000)”. La lista dei riferimenti bibliografici deve essere fatta in ordine Tavole fuori testo (per esempio: carte geologiche, alfabetico e per lo stesso autore in ordine di anno di pubblicazione grandi illustrazioni, …) crescente. Lavori dello stesso autore pubblicati nello stesso anno devono essere specificati con una lettera alfabetica dopo l’anno di Eventuali illustrazioni di dimensioni eccedenti la pagina nor- pubblicazione: “ a”, “b”, “c”, ecc… male della rivista possono essere pubblicate come tavole fuori testo, a carico dell’Autore. Anche in questo caso l’Editore contatterà Esempi della redazione della Bibliografia l’Autore in merito ai relativi costi. Riferimento ad una rivista Tabelle Autore 1, N., Autore 2, N. e Autore 3, N., 2000. Titolo del lavoro. Nome della rivista per esteso. Volume. pp. xx-xx. Le tabelle devono essere numerate consecutivamente secondo l’ordine con cui appaiono nel testo. Riferimento ad un libro Autore 1, N., 1999. Titolo del libro, Editore, luogo di stampa. Didascalie delle figure e tabelle Riferimento a un capitolo in un libro – Ogni figura e tabella deve avere una didascalia che ne descri- Autore 1, N., Autore 2, N. e Autore 3, N., 2000. Titolo capitolo, va chiaramente e in modo esaustivo il contenuto. in: Autore libro 1, N., Autore libro 2 N. (Eds.), Titolo libro, – Il titolo deve essere riportato nella didascalia e non sulla figu- Editore, Luogo di edizione, pp. xx-xx. ra o nelle tabelle. – Il testo della didascalia deve essere conciso ma vi devono es- Riferimento ad un articolo pubblicato sugli atti di un convegno sere spiegati tutti i simboli e le abbreviazioni usate. Autore 1, N. e Autore 2, N., 2000. Titolo articolo, in: titolo conve- – Le didascalie devono essere redatte in due lingue: Italiano e gno per esteso, data di svolgimento, Luogo di svolgimento, Inglese. Editor 1, N., Editor 2 N. (Eds), Ente organizzatore convegno, pp. xx-xx. Citazioni bibliografiche La rivista “Geoingegneria Ambientale e Mineraria” va sempre – Verificare che tutte le citazioni bibliografiche indicate sul te- indicata con il nome completo e per esteso, si devono evitare ab- sto siano presenti in bibliografia (e viceversa). breviazioni.

Dicembre 2017 147 atti dell’associazione

Pubblicazioni monografiche Atti del Convegno “Rischio idrogeologico, opere di Quaderno N. 24 Studi conoscitivi sui bacini marmiferi difesa ed uso del territorio nel Canavese”, Ivrea, 8-9 industriali di Carrara: un contributo per la gestione Atti del Convegno “Tecnologia dell’idrofresa per rea- maggio 1998. pianificata dell’attività. lizzare diaframmi profondi in terreni difficili”, Torino, Atti della Giornata di Studio “Aspetti tecnici e norma- Quaderno N. 23: a cura del CNR-IRPI, Torino, “Inda- 16 settembre 2010. tivi nell’estrazione di inerti e pietre calcaree per uso gini geologico-morfologiche su aste torrentizie della Atti della Giornata di studio “Lo stato di attuazione industriale”, Torino, 13 novembre 1997. Valtellina e della Valle di Susa ricorrentemente sog- delle carte di rischio da frana per la difesa preven- Atti del Workshop “La città sotterranea”, Torino, 6 gette a colate detritiche torrentizie (debris flow). tiva del territorio italiano dalle catastrofi naturali” dicembre 1996. Quaderno N. 22: M. Fornaro – L. Bosticco, “La coltiva- (CD Rom), Milano, 3 dicembre 2009. Atti della Giornata di Studio “La protezione contro zione in sotterraneo delle rocce ornamentali”. Atti del Convegno su “Vuoti minerari: risorsa o pro- la caduta massi dai versanti rocciosi”, Torino, 24 ot- Quaderno N. 21: a cura del CNR – IRPI, Cosenza, blema?” (CD Rom), Torino, 5-6-7 giugno 2008. tobre 1996. “Problematiche di geologia applicata nella realizza- Atti del Workshop su “Inquinamento atmosferico in Atti del Convegno “L’impatto dell’attività industriale zione della galleria ferroviaria Paola-Cosenza”. ambiente urbano: Torino – Milano – Lyon – Lon- sulle risorse idriche sotterranee”, Cernobbio 22-24 Quaderno N. 20: a cura del CNR – IRPI, Torino, “Studi dra”, Torino, 7 novembre 2007. /05/96. sui Debris flow”. Atti della Seminario su “Bonifiche dei siti contaminati: Atti del Convegno “L’acqua nel sottosuolo: utilizzazio- esperienze in campo e sviluppi della normativa at- Quaderno N. 19: a cura del CNR – IRPI, Cosenza, ne e salvaguardia-Aspetti geologici, idraulici, geotec- “Il nubifragio del 13 marzo 1995 in Calabria meri- tuale”, Racconigi, 19 settembre 2007. nici e ambientali” (estratto rivista IGEA n. 4 1995), Atti del Seminario “Nanotecnologie e Ambiente: fer- dionale e Sicilia Orientale. Le alluvioni in Calabria Taormina, 11 -12 -13 Maggio 1995. – Rapporto sull’evento del 13 e 14 marzo 1995: ro nanoscopico per la bonifica di acquiferi contami- Monografia “Vibrazioni” E&B-Torino, 1994. nati”, Torino, 27 marzo 2007. acquisizione dati ed analisi idrologica a scala regio- Atti del IV Convegno di Geoingegneria “Difesa e valo- nale.”. Atti del Convegno “Le risorse lapidee dall’antichità ad rizzazione del suolo e degli acquiferi”, Torino, 10-11 oggi in area mediterranea”, Canosa, 25-27 settem- Quaderno N. 18: a cura del CNR – IRPI, Torino, “L’e- marzo 1994 (3 Volumi). vento alluvionale del 23-25 settembre 1993 in Li- bre 2006, 1° volume – 2° volume. Atti del Convegno “De Re Metallica-Miniere e ma- Proceedings of the fifteenth International Symposium guria e Valle d’Aosta. Aspetti idrologici e geomor- terie prime alle soglie del 3° millennio”, Torino, di- fologici”. on “Mine planning and equipment selection”, Torino, cembre 1994. 20-22 settembre 2006 (2 Volumi o CD rom). Quaderno N. 17: a cura del CNR – IRPI, Torino, “Si- Atti del III Convegno di Geoingegneria “Scavo in roc- tuazioni di rischio geologico e idraulico in aree for- Atti del Convegno “Le cave in sotterraneo”, Torino, cia: il futuro ed il futuribile”, Torino, dicembre 1992. 20-21 giugno 2006. temente antropizzate. Gli eventi alluvionali del 1° Atti della Giornata di Studio su “Il futuro dell’approv- giugno 1992 in provincia di Varese e del 22 luglio Atti del Convegno “L’ingegneria e la neve” (CD rom), vigionamento idrico in Italia”, Torino, dicembre 1991. Torino, 21 febbraio 2006. 1992 nella conca di Bormio in Valtellina”. Atti dell’ Incontro di Studio su “La meccanica delle Quaderno N. 16: M. Govi – O. Turitto, “Ricerche bi- Atti del Convegno “AVR 05 – Aquifer Vulnerability rocce a piccola profondità”, Torino, ottobre 1991. and Risk – 2nd Workhop and 4° Convegno Nazio- bliografiche per un catalogo sulle inondazioni, piene Atti del 1° Convegno Internazionale di Geoingegneria torrentizie e frane in Valtellina e Valchiavenna”. nale sulla Protezione e Gestione delle Acque Sot- “ Suolosottosuolo”, Torino, settembre 1989 (3 Volu- terranee (Riassunti + CD rom), Reggia di Colorno- Quaderno N. 15: P. Manni, “La V.I.A. delle attività mi) – solo 3° Volume. estrattive ed i criteri di recupero delle aree oggetto Parma, 21-23 settembre 2005. Atti della Giornata di Studio su “Problemi ambientali Atti del Convegno “Scavo Meccanizzato di Gallerie: di coltivazione”. delle attività di cava in Piemonte: gestione e pro- Quaderno N. 14: “Esperienze europee di valorizza- challenging case histories”, Torino , 16-19 novembre grammazione” Torino, marzo 1985. 2004. zione turistico culturale del patrimonio minerario” Atti del Convegno sui Trafori del Piemonte e della Val- – Atti del Convegno Internazionale – Perosa Argen- Atti del Convegno “Bonifica dei versanti rocciosi per le d’Aosta, Torino, ottobre 1981-maggio 1983. la protezione del territorio”, Trento , 11-12 marzo tina, ottobre 1993. Final Report on the joint U.S. – Italy Workshop on Quaderno N. 13: a cura del CNR – IRPI, Torino, “Even- 2004. “Characterizing and modeling rock mass for design Atti del Convegno “I minerali per l’industria”, Torino, ti alluvionali in Liguria. Studio idrologico e geomor- and construction of underground cavities”. fologico”. 9-10 giugno 2003. Atti del Convegno su “La coltivazione di cave per Atti del Convegno “Le acque sotterranee nella Pianura Quaderno N. 12: G. Gottardi, “L’applicazione dei me- inerti: attualità e prospettive”, Torino, ottobre 1981. todi di calcolo delle perdite di carico per moto po- Padana: studi, gestione e tutela, Parma, 10 aprile 2003. Dibattito su “Aspetti tecnici ed economici attuali Atti del Convegno “ACUUS 2002 International Con- lifasico nelle condotte verticali di piccolo diametro”. dell’approvvigionamento dei metalli”, Torino, dicem- Quaderno N. 11: G. Charrier, “Documenti di paleocli- ference – Urban Underground Space: a Resource bre 1978. for Cities” (Riassunti + CD rom), Torino, 14-16 nomi del Pliocene terminale, Pleistocene ed Olocene Atti della Giornata di Studio su “La bullonatura in sot- nel territorio della Valle di Susa e sue adiacenze”. vembre 2002. terraneo”- Torino, ottobre 1978. Atti del Convegno “Le indagini geologiche e geotec- Quaderno N. 10: D. Tropeano, “Eventi alluvionali e fra- Atti della Giornata di Studio su “La Miniera di Salafos- ne nel Bacino della Bormida. Studio retrospettivo”. niche propedeutiche alla costruzione delle opere sa”, Salafossa, giugno 1978. sotterranee sia civili che minerarie”, Modena, 18 Quaderno N. 9: G. Baldini, “Pressione allo stand-pipe Atti della Giornata di Studio su “Scavo di gallerie in nell’appesantimento (e nell’alleggerimento) del fan- maggio 2002. roccia con frese a piena sezione”, Torino, aprile Atti del Convegno “L’innovazione tecnologica negli go di perforazione, eseguito con valori generici di 1975. volume, densità di massa e portata”. scavi verso lo sviluppo compatibile con l’ambiente” Atti della Giornata di Studio su “Sgombero del mari- Quaderno N. 8: G.P. Giani, “Analisi di stabilità dei pen- – Verona, 15 febbraio 2002. no in galleria”, Torino, ottobre 1976. Atti del Convegno “Biogas da discarica – problemati- dii – Parte 1: Classificazione dei fenomeni di instabi- Atti della Giornata di Studio su “La Miniera di Raibl”, lità, pendii naturali e fronti di scavo in roccia”. che ed opportunità”, Torino, 8 aprile 2002. Torino, marzo 1976. Atti del Convegno “Controllo ambientale della attività Quaderno N. 7: G. Gottardi et al., “CFEWO: Program- Atti del 1° Convegno Internazionale sulla coltivazione ma ad elementi finiti per la simulazione di giacimenti di cava per lapidei ornamentali in importanti bacini di pietre e minerali litoidi, Torino, ottobre 1974 (3 di idrocarburi bifasici”. estrattivi” – Trani (BA), 20 novembre 2001. Volumi). Quaderno N. 6: L. Musso et al., “La miniera di Funtana Atti del Convegno “Opere di difesa da caduta massi”, Atti della giornata di Studio su “Le fluoriti italiane”, Siusi (BZ), 18-19-20 ottobre 2001. Torino, dicembre 1972 (2 Volumi, 5 Tomi). Raminosa”. Atti del Seminario Internaz. “Le pietre ornamentali Atti delle Giornate di Studio su Gli esplosivi nei lavori Quaderno N. 5: G. Ferrara et al., “Riorganizzazione del della montagna europea”, Luserna San Giovanni – di abbattimento in campo civile e minerario: innova- bacino estrattivo di sali potassici della Sicilia”. Torre Pellice, 10-12 giugno 2001. zioni e problemi”, Torino, ottobre 1970. Quaderno N. 4: G. Baldini, “Manovre idrauliche per la Atti del Convegno “Le cave di pietre ornamentali”, Atti del 1° Convegno Internazionale sui problemi tec- prevenzione della eruzione di gas nella perforazio- Torino, 28-29 novembre 2000. nici nella costruzione di gallerie, Torino, settembre ne petrolifera”. Atti del Convegno su “Tecniche e metodologie avan- 1969 (4 Volumi). Quaderno N. 3: A. Balossi Restelli et al., “Tecniche di zate di monitoraggio discreto e continuo delle ac- congelamento del terreno per lo scavo di gallerie”. que sotterranee”, Torino, 21 novembre 2000. Quaderno N. 2: G. Barla et al., “L’applicazione dei Atti del Convegno “Il DM 471 del 25 ottobre 1999 metodi dell’equilibrio limite nello studio dei pendii – Guida applicativa agli interventi di bonifica dei siti Quaderni di studi e di documentazione naturali e delle scarpate”. inquinati”, Torino, 11 luglio 2000. Quaderno N. 25 D. Peila – C. Oggeri – P. Baratono, Quaderno N. 1: G. Baldini et al. “Funzioni di diffusione Atti del Convegno “Previsione e prevenzione di movi- “Barriere paramassi a rete – Interventi e dimensio- per un declino uniforme, nella sezione di erogazio- menti franosi rapidi”, Trento, 17-18-19 giugno 1999. namento”. ne del potenziale o del gradiente del potenziale”

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