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The evaluation of the reference earthquake for the siting of high risk industrial plants Aim of this paper is to recommend a methodology for the proper assessment of the risk associated with the operation of hazardous industrial plants, largely distributed all around the world, with emphasis on the potential earthquake effects. This type of risk, in-fact, in the Author’s opinion is still very poorly understood by society. The industrial Augusta-Priolo Gargallo area has been chosen as an example

■ Leonello Serva, Fiorenzo Fumanti

La valutazione del rischio di incidente rilevante dovuto a terremoti nella scelta dei siti di impianti industriali In questo lavoro viene proposta una metodologia per la valutazione del rischio associato al funzionamento di impianti a rischio di incidente rilevante, diffusi in tutto il mondo, con particolare enfasi agli effetti di potenziali terremoti. È opinione degli Autori che tale tipo di rischio sia poco conosciuto dalla società. Come caso di studio è stata scelta l’area industriale di Augusta-Priolo Gargallo

he last strong earthquakes that have affected very of what stated above, it is time to apply the siting ap- T populated areas (Kocaeli, Turkey, Aug. 17 1999, proach also to these facilities. As for the NPPs, it can be Mw=7.4, Figure 1; Guyarat, India, Jan. 26 2001, Mw=7.7; applied also a posteriori and, because of that, a priori- Tohoku, Japan, Mar. 11 2011, Mw=9.0, Figure 2) have ty should be given to the existing very industrialized clearly highlighted that high risk plants, such as che- areas of the world in order to be aware with the level mical plants and refi neries, can be deeply affected of risk there present and start appropriate actions, if and therefore, as the Nuclear Power Plants (NPPs), can necessary. The case of the Italian Augusta-Priolo Gar- create signifi cant additional risk to human beings, pro- gallo (Syracuse, Sicily) area is here examined. perty and the environment. In this paper we want stress the concept that, because Methodology (summarised and customised from the IAEA Technical Guide Series No. SSG-9) ■ Leonello Serva Past Coordinator of the Working Group ISPRA for the technical Siting is the process of selecting a suitable location for support to IPPC/AIA Commission of MATTM. Member of Scientific Committe of ISSC of IAEA any type of facilities, based on the appropriate asses- ■ Fiorenzo Fumanti sment and defi nition of the design parameters in order ISPRA - Geological Survey of Italy to protect the facility from environmental hazards and to

EAI Energia, Ambiente e Innovazione 3/2012 72 As saidabove, sitingisthedemonstration oftheaccep- environment from unduetoxic hazards. resulting inprotection ofworkers, thepublic andthe

FIGURE2 FIGURE1 ■ ■ ■ theachievement isinfact Safety of: minimize theimpactofplanttoenvironment.

mitigation ofaccidentconsequences, prevention ofaccidentsor proper operating conditions, Fire boatsfi Tupras Refi March 12, 2011 facility inIchiharaCity, Chiba Prefecture nearTokyo Source: REUTERS/Kyodo,InFocusby Alan Taylor, TheAtlantic Source: GayleJohnson,2002 1999, M=7.4earthquake nery, Korfez,IzmitBay(Turkey). August17, ghting againstablazeattheCosmo Oil Therefore sitingresults intheanalysis of: hydrology, meteorology. civil engineering, soilmechanics, geology, seismology, gineering, ecology, demography, emergency planning posed by inpower experts engineering, chemical en- facility. properThe thejobiscom- teamtoperform and derivation ofthesite-related the designbasesfor tability ofthesiteonbasisestablished criteria lability ofcoolingwater, Others. tion distribution, Emergency planning, Landuse, Avai- induced events, Dispersioninairandwater, Popula- Flooding, Extreme meteorological phenomena, Human faulting,and surface material, Subsurface Vulcanism, the determinationoffollowing hazards: Seismicity all features andareas thatcouldbeofsignifi size oftheregionThe shallbelarge enoughtoinclude nal phenomena. establishing thehazards associated withmajorexter- and evaluated. Appropriate methodsshallbeusedfor of theoccurrences ofsuchevents shallbecollected and instrumentally recorded andrecords information operationsafe ofthefacility. Pre-historical, historical and evaluated according totheirsignifi tuations andactivities intheregion shallbeidentifi Possible natural phenomena andhumaninducedsi- ■ ■ na is the Augusta-Priolo Gargallona istheAugusta-Priolo territory, historical- activities andtheirinteraction withnatural phenome- blems related tothehighconcentration ofindustrial are out. carried Particularly representative ofthepro- complexesgated inindustrial where several activities Usually ofaccidentare theplantswith highrisk aggre- of Augusta-PrioloGargallo Seismic hazard andthecase ■ to theenvironment, the transferofreleased contaminantstopersonsand of thesiteanditsenvironment which couldinfl oftheplantonregioneffects –i.e., characteristics natural orman-inducedorigin, events intheregion, occurring which couldbeof oftheregioneffects ontheplant–i.e., external of implementingemergency measures. andothers)inrelationdistribution tothepossibility population characteristics oftheregion (i.e., density, EAI

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Studi & ricerche REVIEW & ASSESSMENT PAPERS ly affected by violent earthquakes and high-intensity tsunami events (Table 2). At present, the area presents more plants with high accident risk (three refi neries, two petrochemical plants, one gas storage plant, one explosive deposit, one thermoelectric plant with he- avy refi nery residues combustion, three mineral oil deposits, one gas production plant and a consortium plant for wastewater treatment) and other industrial or energy settlements. The hazards related to earthquake are: ■ the ones linked to the Vibratory Ground Motion (VGM) in term of acceleration, velocity and displa- cement of the earth surface (Class (1) features that can substantially infl uence the severity of the design basis earthquakes; ■ the ones linked to the associate phenomena of the quake, like the potential: surface faulting (the per- FIGURE 3 Seismogenic tectonic structures of interest for the manent offsetting or tearing of the ground surface defi nition of the VGM at Augusta-Priolo Gargallo by differential movement across a fault during an Source: APAT, 2004 earthquake); tsunami (if the area is on the coastline), areal uplifting/subsidence; ground collapse; lique- faction and landsliding (Class (2) features that can fi c and complete database for the construction of a have direct infl uence also on the acceptability of the seismotectonic model from which the potential ear- site. thquakes affecting the site can be derived. These earthquakes are then used to defi ne the nature of Class (1) features earthquakes used as a basis for design of the facility. Class (1) features defi ne the parameters of the Thus, it is essential to obtain an integrated geologi- ground motion of the design-basis earthquakes. To cal and seismological database. The elements of this reach this goal, it is necessary to compile a speci- database should be studied in greatest detail in the

Seismogenic source Minimum distance Estimated Maximum Geometry Tectonic Style between site hypocentral Magnitude of the source and seismogenic source depth Malta Escarpment- 10-15 km 7.2 340° (strike) Extensional W Catania Gulf 21 km 20-25 km 7.4 60° (dip) Malta Escarpment- 37 km 10-15 km 7.2 340° (strike) Extensional E Catania Gulf 20-25 km 7.4 60° (dip) Lentini Graben 18 km 10-15 km 6.2 250° (strike) Extensional 20-25 km 6.4 60° (dip) Climiti Mount 8 km 10-15 km 5.7 320° (strike) Extensional 20-25 km 5.9 60° (dip) Avola - Noto 30 km 10-15 km 6.0 30° (strike) Extensional 20-25 km 6.2 60° (dip)

TABLE 1 Characteristics of the seismogenic sources of Figure 3

EAI Energia, Ambiente e Innovazione 3/2012 74 thquake loading. their stabilityandresponse underdynamic ear- andthedeterminationof materials the foundation phasize thedefi features). Investigations atthesitearea shouldem- identifying sources ofpotentialinstability(Class2 capability)and atthesite(fault faulting of surface ofresolvingwith thespecialpurpose thepossibility ne ingreater offaults detailtheneotectonichistory vicinity, asalready mentioned, isdesignedtodefi sessment ofseismichazards. Investigation ofthesite more seismogenic important structures theas- for near regional investigations istocharacterize the seismic hazard atthesite. ofthe mainpurpose The those seismogenic features thatmay infl and itsgeneral geodynamic settingandtoidentify de knowledge ofthetectonicframework oftheregion oftheregional mainpurpose The studiesistoprovi- of thesite, andtheimmediatearea ofthesite. are appropriate: regional, nearregional, thevicinity plete. Inthisconnection, scalesofinvestigation four region closetothesitewhere itwillbemore com- nition ofthephysical properties of une the uence - Regarding the potential for the surface faulting ha- Regarding faulting thesurface thepotentialfor data(Tablehistorical 2). cording totheMagnitudeofsource zone andthe dataareimportant themodelingoftsunamiac- thedetails)arefor reported. Ofcourse, othervery sment ofthetsunamihazard inthearea (seefi theasses- gical data(thesocalledtsunamites)for Regarding thetsunami, inFigure 4, 5, 6, thegeolo- Gargallo theAugusta-Priolo tant for area. presence are ofcapable faults particularly impor- oftsunamiandthepotential potentialeffects The commended. economically unfeasible, anothersiteshouldbere- of applying themissuchthattheproject becomes solutions are notavailable or, ifavailable, thecost For theClass(2)features citedabove; ifengineering Class (2)features hazard Gargallo intheAugusta-Priolo area. above, signifi seismogenic sources, derived by thestudiescited Figure 3and Table 1represent, asanexample, the theassessmentofseismiccant for

FIGURE4 EAI Stratigraphic log of Priolo (SR) StratigraphiclogofPriolo(SR)

570-122 B.C). paleotsunami (1693(A);1169(B); the coastline)withevidenceof coastal plain(about500mfrom Source: Smedileetal.,2007 Energia, AmbienteeInnovazione

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Studi & ricerche REVIEW & ASSESSMENT PAPERS FIGURE 5 Geological evidence of paleotsunami in the Augusta-Priolo Gargallo area (Ognina section, events ) Source: Scicchitano et al., 2008

zard in the Augusta-Priolo Gargallo, it is fi rst impor- may be appropriate for the assessment of capable tant the defi nition of this feature, that is: a fault is faults. In less active areas, it is likely that much lon- considered capable if it shows evidence of past mo- ger periods may be required. When faulting is known vement (signifi cant deformation and/or dislocation) or suspected, investigations should include detailed of a recurring nature within such a period that it is geological-geomorphological mapping, topographi- reasonable to infer that further movement can occur cal analyses, geophysical (including geodesy, if ne- at, or near the surface. In highly active areas, where cessary) surveys, trenching, boreholes, determining both earthquakes and geological observations consi- ages of faulted sediments or rocks, local seismologi- stently reveal short earthquake recurrence intervals, cal investigations and any other appropriate techni- periods of the order of tens of thousands of years ques, to ascertain when the last movement occurred.

FIGURE 6 Scattered boulders deposited on the Priolo coastal area after the 1169 and 1693 Tsunami events Source: Scicchitano et al., 2007

EAI Energia, Ambiente e Innovazione 3/2012 76 tity andtypeofgeological, geophysical, seismologi- detailsrequiredThe onthedatabase (quality, quan- A fi sented inFigure 8and9(seethedetailsinfi Two thisproblem technicalsolutionstoface are repre- Gargallonear vicinityofthePriolo siteare reported. In Figure locatedinthe 7thepotentialcapable faults TABLE 2 Cd Itniy antd Intensity 2 Magnitude 2 6 Intensity 5.7 6 4 7.2 6 5 2 5.9 7 6.9 3 11 9 7.4 ER 6 8.5 4 ER 11 EA 4 EL 11 4 8.5 6.6 Sicilia EA Orientale 4 Stretto 4 ER 13 Messina Sicilia ER Orientale Tsunami 28 4 Stretto Messina 10 20 12 4 Earthquake Intensity oftsunami:1verylight;23ratherstrong; 4strong; 5verystrong; 6disastrous (Sieberg-Ambraseys Tsunami Calabria 6 tirrenica 12 2 Cause: EAearthquakeassociated;VA volcanoassociated;ERsubmarineearthquake. VA 1990 Earthquake Reliability: 0veryimprobable; 1improbable; Sicilia 2questionable;3probable; 4defi 5 2 ER Orientale 1908 Sicilia Cause 66 Orientale 2 11 2 1818 54 Reliability 9 2 4 Sicilia 1783 38 Orientale 1 Sicilia 1783 28 Orientale Subregion 27 1 4 1693 26 6 1693 15 Day 2 1329 14 1169 Month 4 Year 3 Code Id_ nal hypothesis nal Tsunami occurredSicilyduringthelastmillenniumaccording intheIoniancoastofsouth-eastern tocatalogueTintiet gures). nite. industrial areaindustrial containingdifferent typesofplants, ving thesamelevel ofanNPP, ofrisk however an It isevident thatthere are plantsha- nohighrisk the NPPsisreported. between thesefacilities, thecivil and constructions plantunderanalysis.risk InFigure 10acomparison to thelevel ofrisk/environmental impactofthehigh data)should bestrictlylinkedcal andengineering

FIGURE7 EAI Capable and suspected capable Capable andsuspectedcapable

fault around thePrioloGargallo area Source: ISPRA,ITHACAProject Energia, AmbienteeInnovazione Intensity Scale)

al.(2004) 3/2012 77

Studi & ricerche REVIEW & ASSESSMENT PAPERS FIGURE 8 Trans-Alaska Pipeline - Before and after the 2002 earthquake. At the Denali Fault crossing, the pipeline is supported on 33 steel box beams and concrete beams. These beams were sized and arranged to accommodate a fault slip. Note movement and bowed segment after fault displacement, which acts to compress the pipeline crossing segment Source: modifi ed after http://gallery. usgs.gov

FIGURE 9 Megara to Korinthos High Pressure Natural Gas Pipeline. FIGURE 10 Level of risk of High Risk Plants Encasing of pipeline at active faults crossings Source: http://users.ntua.gr/gbouck/proj-photos/megara.html

including some dealing with very toxic substances can cause relevant risks on man and/or the natural (Tables 3 and 4), in the Author opinion, should be environment in terms of areal extension and level treated only a little less than an NPP; the Augusta- of contamination. A similar concept is also expres- Priolo Gargallo area and others in the Italian territo- sed by Gurpinar, 1997. In such a case, as for the ry should be treated very similar to an NPP. For some nuclear, we should define, as design earthquake aspects, also a single plant dealing with very toxic SL2 the maximum potential earthquake, i.e., the material located in an intensively populated area ten thousand years return period earthquake. The (e.g., downtown) and a large dam should be treated engineering treatment of this earthquake can be in a similar way. significantly different from the one defined in the More in general we can say that the methodology nuclear, and this theme is not treated here. Class 2 should be similar to the NPPs when we are dea- features should be analyzed with the same details ling with a system of plants for which an accident of the nuclear.

EAI Energia, Ambiente e Innovazione 3/2012 78 TABLE 3 APPA) canplay asignifi stem oftheEnvironmental Agencies (ISPRA-ARPA- also dataandexpertise; inthisregard theItalianSy- of suchplants, by providing notonly guidancebut at nationalandlocalscales, shouldhelptheowners the solutionofproblem, andpublic institutions, synergy reduction (intermsofcost/risk benefi the owners oftheseplantscouldwork inaweighted theplantlifetime.during Inany case, Ibelieve that ver, thebenefi It isevident thatitisahighly costapproach. Howe- Phosgenestoragesandprocess users Large Chlorinestorages Large dieseloilorfueltankfarms For Environment Large VLPG storageplants For Man Mosthazardous industrialplants t isalsohighincasesuchevent occurs cant role. cant t) for t) several areas ofthe Italianterritory, asproved by and theexisting cataloguesare stillincompletefor static anddynamic loadsshouldalways beproved particular, thegeological stabilityofthe siteunder thesolutiontoproblems. for not besufficient In seismiccataloguescould Italianhistorical the rich point outthatalsointhiscasethedatacomingfrom center, asludge plant. Itisimportant, however, to anoilpipeline,base for astrategic communication should bethegeological andseismologicaldata- type isreported inBarone etal., 1998. Stillminor ke, asSL2, couldbeadequate. Anapproach ofthis case, the500-1000years return earthqua- period but requiringminor risk anemergency plan. Inthis areastrial and, more ingeneral, plantshaving for from the treating reported material in Table 4thatare taken aling withhazardous plants(Table 3ortheones In themeantimedetailisminorifwe are de- “Seveso2” Law) notlocatedinalarge indu- EAI

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Studi & ricerche REVIEW & ASSESSMENT PAPERS Dangerous substances Qualifying quantity (tonnes) for the application of the Law Ammonium nitrate 350 2500 Ammonium nitrate 1250 5000 Arsenic pentoxide, arsenic (V) acid and/or salts 1 2 Arsenic trioxide, arsenious (III) acid and/or salts - 0,1 Bromine 20 100 Chlorine 10 25 Nickel compounds in inhalable powder form (nickel monoxide, nickel dioxide, nickel sulphide, trinickel disulphide, dinickel trioxide) - 1 Ethyleneimine 10 20 Fluorine 10 20 Formaldehyde (concentration ( 90 %) 5 50 Hydrogen 5 50 Hydrogen chloride (liquefi ed gas) 25 250 Lead alkyls 5 50 Liquefi ed extremely fl ammable gases (including LPG) and natural gas 50 200 Acetylene 5 50 Ethylene oxide 5 50 Propylene oxide 5 50 Methanol 500 5000 4, 4-Methylenebis (2-chloraniline) and/or salts, in powder form - 0.01 Methylisocyanate - 0.15 Oxygen 200 2000 Toluene diisocyanate 10 100 Carbonyl dichloride (phosgene) 0,3 0.75 Arsenic trihydride (arsine) 0,2 1 Phosphorus trihydride (phosphine) 0,2 1 Sulphur dichloride 1 1 Sulphur trioxide 15 75 Polychlorodibenzofurans and polychlorodibenzodioxins (including TCDD), calculated in TCDD equivalent - 0.001 The following CARCINOGENS: 4-Aminobiphenyl and/or its salts, Benzidine and/or salts, Bis(chloromethyl) ether, Chloromethyl methyl ether, Dimethylcarbamoyl chloride, Dimethylnitrosamine, Hexamethylphosphoric triamide, 2-Naphtylamine and/or salts, and 1,3 Propanesultone 4-nitrodiphenyl 0.001 0.001 Automotive petrol and other petroleum spirits 5000 50000

TABLE 4 Dangerous substances according to the “Seveso2” Law

EAI Energia, Ambiente e Innovazione 3/2012 80 references tial motionofbridgesandlifelines, sinceitenables oftherealisticimportance defi 1997 shouldbeemphasized andsoshouldthegreat Richter relationship by asdescribed Mochanetal., application oftheGutenberg-limit oftheacritical plants.dustrial Regarding theselongstructures, the should beconsidered asthethird categoriesofin- because ofthat, Ibelieve thatalsothesestructures by active (Azzaro (capable) fault etal., 1998)and geological framework, suchasItaly, canbecrossed well known, infact, thatthesestructures inayoung reduction,risk especially inemergency phases. Itis facilities, galleries, canplay asignifi structures,industrial like bridges, communication to point outhereIt isimportant thatalsoothernon chetti etal., 2000). the ongoing paleoseismologicaltechniques(Mi- APAT, vol. 17,pp.147-162,1998. R. Azzaro, L.Ferreli, A.M.Michetti,LServa,E.Vittori, A. Gurpinar, proceedings 2002. P.E. GayleJohnson, Proposte diLineeguidaperlaverifi ca sismicadiimpiantiarischioincidenterilevante esistenti. D. Barone, G.Macchi,Petrangeli(Coord.), A.Pugliese,ARicchiuti,T. Sanò, IAEA, L. Serva, Geophysics, vol.43,pp.1-95,2001. G.F. Panza,F. Romanelli,F. Vaccari, G. Molchan,T. Kronrod, G.F. Panza, School onActiveFaulting,pp.279-284,2000. Examples fromtheMateseandIrpiniaareas,SouthernApennines. A.M. Michetti,BlumettiA.M.,EspositoE.,Ferreli L.,GuerrieriPorfi E., do S.,ServaL.eVittori IAEA, G. Scicchitano,CostaB.,DiStefanoA.,LonghitanoS.G.,MonacoC., 75–91, 2007. G. Scicchitano,C.Monaco,L.Tortrici, Convegno: Evoluzionegeologicaegeodinamicadell’Appennino L. Serva,A.M.Blumetti,Guerrieri,Michetti, pp. 77-96,1993. S. Tinti, Maramai, A.,Graziani,L., S. Tinti, Augusta Bayarea(easternSicily, Italy):paleoseismologicalimplication. A. Smedile,DeMartiniP.M., BarbanoM.S.,Gerardi F., PantostiD.,Pirrotta C.,CosentinoM.,DelCarloP. P., &Guarnieri Geologica Italiana,6,pp.37-41,2008. SeismicHazardsinSiteEvaluationforNuclearInstallationsSpecifi c SafetyGuide. Site survey andSiteSelectionforNuclearInstallations. Site survey La messainsicurezzadell’areaindustrialediPriolo-Augustarispettoairischidaterremotoemaremoto. An analysis of the major regulatory guidesforNPPseismicdesign(aguidelinehighriskfacilities). An analysisofthemajorregulatory A reviewofseismicsafetyconsiderationsinthelifecyclecriticalfacilities. http://www.slc.ca.gov/Division_Pages/MFD/Prevention_First/Documents/2002/Paper%20by%20Gayle%20Johnson.pdf Refi DamageandEmergencyResponseinthe1999Izmit,Turkeynery Earthquake.Californiastatelandcommission,PreventionFirst The newcatalogueofItaliantsunamis. Seismic wave propagation in laterally heterogeneous anelastic media: theory andapplicationtotheseismiczonation. Seismic wavepropagationinlaterallyheterogeneousanelasticmedia:theory Multi scaleseismicityforseismicrisk. Large boulderdepositsbytsunamiwavesalongtheIoniancoastofsouth-eastern Sicily(Italy), nitionofthedifferen- cant role inthe The Apenninic intramountain basin: the results of repeated strong earthquakes over a geological time interval. Attidel The Apenninicintramountainbasin:theresultsofrepeatedstrongearthquakesover ageologicaltimeinterval. Environmental hazardofcapablefaulting:thecasePernicanafault DS433, SafetySeries50-SG-S9,1984. -InmemoriadelProf. GiampaoloPialli.Foligno,16-18febbraio2000. In:“ActiveFaultResearch fortheNewMillennium”,Proceedings oftheHokudanSymposiumand XXVI ConvegnoGNGTS.ExtendedAbstractVol., pp.207-211,2007. Tsunami deposits intheSiracusacoastalarea(south-easternSicily). Nat. Hazards 33,pp.439–465,2004. BSSA,Vol. 87,no5,pp.1220-1229,1997. uoenpat. European plants. thout asignifi has beenandispresently donesuccessfully andwi- tions toincrease itssafety. work,This inthenuclear, such acase, itpermits todefi can bedonealsoiftheplantisalready existing. In topointitoutthatsiting At thispointitisimportant dreds thousandsofyears. oftensorhun- should bedemonstrated periods for In suchcase, inparticular, thestabilityofsite highlevelis thecaseofsitesfor radioactive waste. could bemuchhigherthanrequired NPPs, for this On theotherhand, thequantityandqualityofdata ourpurposes. for syntesis (e.g. Panza etal., 2001)particularly suitable and siteeffects, makingthedeterministicseismo- to take intoaccountwave passage, lossofcoherency Comitato Termotecnico Italiano,Sottocomitato7:Gruppo“Tecnologie diSicurezza”. SeriesNo.SSG-9,2010. Journal ofEarthquakeEngineering,Vol.1,Journal pp.57-76,1997 Unpublished,1998. Earthquake GroundEffectsandSeismicHazardAssessmentinItaly: cant economicalcost, many for Eastern Rapporti APAT, vol.41,28pp,2004 EnergiaNucleare, Anno10,n.2,maggio-agosto1993, EAI

Energia, AmbienteeInnovazione Identifi cation ofpaleotsunamidepositsinthe solu- ne engineering (Mt.Etna,Sicily).NaturalHazards. U.K., MarineGeology, vol.238,pp. RendicontidellaSocietà

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