DaS Application Form Version 1/10
This is a draft document and is subject to revision.
Dumping at Sea Permit Application Form
o EPA Ref. N : (Office use only) For inspection purposes only. Consent of copyright owner required for any other use.
Environmental Protection Agency PO Box 3000, Johnstown Castle Estate, Co. Wexford Lo Call: 1890 335599 Telephone: 053-9160600 Fax: 053-9160699 Web: www.epa.ie Email: [email protected]
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Tracking Amendments to Draft Application Form
Version Date Amendment since Reason No. previous version V.1. 07/09/2010 N/A V.2. 27/07/2011 V.1. Clerical update
For inspection purposes only. Consent of copyright owner required for any other use.
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CONTENTS Page
TRACKING AMENDMENTS TO DRAFT APPLICATION FORM 2
ABOUT THIS APPLICATION FORM 4
PROCEDURES 5
SECTION A: GENERAL 7
SECTION B: LOADING OPERATIONS 11
SECTION C: MATERIAL ANALYSIS 13
SECTION D: IMPACT ON THE RECEIVING ENVIRONMENT 15
SECTION E: DUMPING OPERATIONS 15
SECTION F: MONITORING 17
For inspection purposes only. SECTION G: DECLARATIONConsent of copyright owner required for any other use. 18
ANNEX 1: TABLES/ATTACHMENTS 19
ANNEX 2: APPLICATION CHECKLIST 21
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ABOUT THIS APPLICATION FORM
This form is for the purpose of making an application for a Dumping at Sea permit under the Dumping at Sea Acts, 1996 to 2010.
The application form must be completed in accordance with the instructions and guidance provided in the Dumping at Sea Permit Application Guidance Note. The guidance note gives an overview of Dumping at Sea permitting, outlines the permit application process (including the number of copies required) and specifies the information to be submitted as part of the application. The guidance note and application form are available to download from the Licensing page of the EPA’s website at www.epa.ie.
A valid application for a Dumping at Sea permit must, as a minimum, contain the information set out in the First Schedule to the Dumping at Sea Acts, 1996 to 2010. This application form is designed to set out the relevant questions in a structured manner and not necessarily in the order presented in the First Schedule. In order to help ensure a legally valid application in respect of these requirements, please complete the checklist provided in Annex 2.
This application form does not purport to be, and should not be considered, a legal interpretation of the provisions and requirements of the Dumping at Sea Acts, 1996 to 2010. While every effort has been made to ensure the accuracy of the material contained in the application form, the EPA assumes no responsibility and gives no guarantee or warranty concerning the accuracy, completeness or up-to-date nature of the information provided herein and does not accept any liability whatsoever arising from any errors or omissions.
Should there be any contradiction between the informational requirements set out in the application form and any clarifying explanation contained in the accompanying guidance note, then the requirements in this application form For inspection purposes only. shall take precedence. Consent of copyright owner required for any other use.
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PROCEDURES
The procedure for making and processing of applications for Dumping at Sea permits and for the processing of reviews of such permits is summarised below. The application fee that shall accompany an application is currently set at €63.49.
Within 21 days after the submission of an application to the Agency the applicant must publish in a newspaper circulating in the area, a notice of the application, in accordance with Section 5A of the Dumping at Sea Acts, 1996 to 2010. Following publication of the aforementioned notice, any persons who wish to do so may make a submission or comment on the permit application. The permit application and all submissions by third parties shall be put on public display in electronic format on the EPA website and be open to inspection by any person, as soon as reasonably possible by the Agency.
An application for a permit must be submitted on the appropriate form (available from the Agency) with the correct fee and should contain relevant supporting documentation as attachments. The application should be based on responses to the information requested in the form and include supporting written text and the appropriate use of tables and drawings. Where multiple loading or dumping sites are proposed in a single application, a system of unique reference numbers should be used to denote each loading and dumping site. These should be simple, logical, and traceable throughout the application.
The application form is divided into a number of sections of related information. The purpose of these divisions is to facilitate both the applicant and the Agency in the provision of the information and in its assessment. Please adhere to the format as set out in the application form and clearly number each section and associated attachments accordingly. Attachments should be clearly numbered, titled and paginated and must contain the required information as set out in the application form. Additional attachments may be included to supply any further information supporting the application. Any references made to publications should be supported For by inspection a bibliography. purposes only. Consent of copyright owner required for any other use.
All questions should be answered. Where information is requested in the application form which is not relevant to the particular application, the words “not applicable” should be clearly written on the form. The abbreviation “N/A” should not be used.
Additional information may need to be submitted beyond that explicitly requested on this form. The Agency may request further information if it considers that its provision is pertinent to the assessment of the application. Advice should be sought from the Agency where there is doubt about the type of information required or the level of detail.
Applicants should be aware that disposing of a substance or material at sea without a permit, or contravening the conditions of a Dumping at Sea permit, are offences under the Dumping at Sea Acts, 1996 to 2010. Offenders are liable upon conviction to a fine or imprisonment or both.
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Note: Drawings and Charts: The following guidelines are included to assist applicants:
• All drawings submitted should be titled and dated. • All drawings should have a unique reference number and should be signed by a clearly identifiable person. • All drawings should indicate a scale and the direction of north. • All drawings should, generally, be to a scale of between 1:20 to 1:500, depending upon the degree of detail needed to be shown. Drawings delineating the loading boundary can be to a smaller scale of between 1:1000 to 1:10560, but must clearly and accurately present the required level of detail. All drawings should be A3 or less and of an appropriate scale such that they are clearly legible. • The applicant should provide legends on all drawings and maps as appropriate. • In exceptional circumstances, where A3 is considered inadequate, a larger size may be requested by the Agency.
A signed original and 1 additional hardcopy of the application and accompanying documents/particulars in hardcopy format plus 2 copies of all files in electronic searchable PDF format on CD-Rom (OCR’d) or other format agreeable to the Agency shall be submitted to the headquarters of the Agency.
It should be noted that it will not be possible to process or determine the application until the required documents have been provided in sufficient detail and to a satisfactory standard.
For inspection purposes only. Consent of copyright owner required for any other use.
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SECTION A: GENERAL
Advice on completing this section is provided in the “Application Guidance Note”.
A.1 Applicant’s Details
Name and Address for Correspondence Only application documentation submitted by the applicant and by the nominated person will be deemed to have come from the applicant. Company Name: Dublin City Council C.R.O.α No.: n/a Address: Drainage Division Block 1, Floor 4, Civic Offices Wood Quay Dublin 8 Tel: +353 1 222 2222 Fax: - e-mail: -
Nominated Contact Person Name*: Owen McManus, Project Engineer Company Name: Dublin City Council, Drainage Division Address: Ringsend WwTW Extension Project Floor 4 68/70 Marrowbone Lane Dublin 8. Tel: +353 1 222 4264 Fax: +353 1 454 6435 e-mail: [email protected]
*This should be the name of a person nominated by the applicant for the purposes of the application. This person may be a company employee or a suitably qualified external For inspection consultant. purposes only. Consent of copyright owner required for any other use. α Company Registration Office.
______
A.2 Planning Authority
Planning Permission relating to the loading works which is the subject of this application: (tick as appropriate)
has been obtained is being processed is not yet applied for is not required
Local Authority Planning File Reference No: An Bord Pleanála File Reference No.: 29N.YA0010
Attachment A.2 should contain, where appropriate, the most recent planning permission, including a copy of all conditions, and where an EIS was required, copies of any such EIS and any certification associated with the EIS, should also be enclosed. Where planning permission is not required for the development, explain why not and provide relevant correspondence, etc.
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Attachment A.2 included Yes No
______
A.3 Other Authorities
A.3 (i) Shannon Free Airport Development Company (SFADCo.) area
The applicant should tick the appropriate box below to identify whether the loading or dumping operations are located within the Shannon Free Airport Development Company (SFADCo.) area.
Attachment A.3(i) should contain details of any or all operations located within the SFADCo. area.
Attachment A.3(i) included Yes No
n/a
A.3 (ii) Health Services Executive Region
The applicant should indicate the Health Services Executive Region(s) where the loading and dumping operations are or will be located.
Name: HSE Dublin South East/Wicklow Address: Vergemount Hall, Clonskeagh, Dublin 6 Tel: (01) 268 0506 Fax: - e-mail: [email protected] For inspection purposes only. Consent of copyright owner required for any other use.
A.3 (iii) Harbour Authority/Local Authority The applicant should indicate the Harbour Authority/Local Authority where the loading and dumping operations are or will be located. In the event that loading and dumping operations take place in separate functional areas, please provide details of all relevant authorities.
Name: Dublin Port Company Address: Port Centre, Alexandra Road, Dublin 1 Tel: (01) 887 6000 Fax: (01) 855 7400 e-mail: [email protected]
Relevant Authorities Notified Yes No
Attachment A.3(iii) should contain a copy of the correspondence issued to all relevant harbour authorities/local authorities.
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Attachment A.3(iii) included Yes No
______
A.4 Newspaper Advertisement
Section 5A of the Dumping at Sea Acts 1996 to 2010, requires all applicants to advertise the application in a newspaper (within 21 days following date of application). See Guidance Note for full details.
Attachment A.4 The original page of the newspaper in which the advertisement was placed must be submitted within 21 days of the advertisement being published.
Attachment A.4 included Yes No
Original notice will be forwarded to EPA once published
______
A.5 FEES
Class of Activity Tonnage Fee (in €) 500,000 — 999,999 tonnes 824,000 €14,000
Appropriate Fee Included Yes No
______For inspection purposes only. ______Consent of copyright owner required for any other use.
A.6 Foreshore Act Licences
Where applicable, provide a copy of the most recent Foreshore Act licence issued under the Foreshore Acts 1933 to 2009 in relation to relevant loading operations at the site. If an application for a Foreshore Act licence pertaining to the operations to which this application relates is currently under consideration by the Minister, outline details of the application should be submitted, including application file number, the date the application was submitted and a brief summary of the operation.
Attachment A.6 should contain the most recent relevant licence issued under the Foreshore Acts 1933 to 2009, including a copy of all conditions attached to the licence and any monitoring returns for the previous 12-month period, if applicable. Outline details of any existing permit applications should be submitted, if applicable.
Attachment A.6 included Yes No
* * Foreshore Licence/ Lease is currently being processed for the jetty to be used for loading.
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A.7 Current/Previous Permits
Provide details of any current or previous permits held by the applicant under the Dumping at Sea Acts, 1996 to 2010.
Attachment A.7 should contain the most recent permit issued under the Dumping at Sea Acts, 1996 to 2010, including any monitoring returns for the previous 12-month period, if applicable.
Attachment A.7 included Yes No
For inspection purposes only. Consent of copyright owner required for any other use.
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SECTION B: LOADING OPERATIONS Advice on completing this section is provided in the accompanying guidance note.
Where development is proposed to be carried out, being development which is of a class for the time being specified under Article 24 (First Schedule) of the Environmental Impact Assessment Regulations, the information on the state of the existing environment should be addressed in the EIS. In such cases, it will suffice for the purposes of this section to provide adequate cross-references to the relevant sections in the EIS.
B.1 Alternative measures Under the provisions of Section 5(2) of the Dumping at Sea Acts, 1996 to 2010, the dumping of substances or material at sea is only acceptable when the Agency is satisfied there is no suitable alternative means of disposal. Provide details of all investigations into alternative means of disposal or reuse of the substance or material. Applicants must also demonstrate that all necessary steps have been taken to minimise the quantity of material to be dumped or to render the material less harmful for dumping at sea. A complete and full answer must be provided.
Attachment B.1 should contain reports and supporting documentation with regard to the investigations into alternative means of disposal, treatment or reuse. Any associated drawings / maps should also be provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84).
Attachment B.1 included Yes No
For inspection purposes only. Consent of copyright owner required for any other use. ______
B.2 Purpose of the operation Provide details on the purpose of the operation, e.g., is the work proposed capital or maintenance loading work. Details of any previous loading at the proposed site(s) should also be included.
Attachment B.2 should contain any supporting documentation on the purpose of the loading operation and details of any previous loading. Any associated drawings / maps should also be provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84).
Attachment B.2 included Yes No
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B.3 Loading Area Four sets of coordinates must be given in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84). If loading at more than one area is to occur, coordinates for additional areas should be appended.
Proposed Pigeon House Jetty Loading area: Latitude Longitude ITM (a) 53° 20' 32'' -6° 11' 39'' E720246, N733978 (b) 53° 20' 33'' -6° 11' 34'' E720335, N733981 (c) 53° 20' 22'' -6° 11' 39'' E720266, N733653 (d) 53° 20' 23'' -6° 11' 41'' E720216, N733697
Proposed Diffuser Site Loading area: Latitude Longitude ITM (a) 53° 19' 45.33" -6° 3' 11.04" E729685, N732768 (b) 53° 19' 45.32" -6° 3' 10.50" E729695, N732768 (c) 53° 19' 46.00" -6° 3' 10.52" E729695, N732758 (d) 53° 19' 45.01" -6° 3' 11.06" E729685, N732758
Attachment B.3: Any associated drawings / maps should be provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84).
Attachment B.3 included Yes No
For inspection purposes only. Consent of copyright owner required for any other use. ______
B.4 Details of the operation Provide details on the following aspects of the operation:
B.4 (I) Date of commencement of loading operations; B.4 (III) Location and method of loading of the substance or material; B.4 (IV) Total quantities (in tonnes and cubic meters) to be loaded:
. per load . per week . per month.
Attachment B.4 should contain any supporting documentation on the details of the loading operations. Any associated drawings / maps should also be provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84).
Attachment B.4 included Yes No
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SECTION C: MATERIAL ANALYSIS Advice on completing this section is provided in the accompanying Guidance Note.
C.1. Tabular data on Sampling Points
Applicants should submit the following information for each sampling point at the loading site(s), at which the material or substance for disposal has been analysed:
PT_CD Latitude Longitude ITM Point Code n/a* n/a* n/a* (Referencing system outlined in guidance notes, e.g. L1-1) An individual record (i.e., row) is required for each sampling point. Acceptable file formats include Excel, Access or other upon agreement with the Agency.
If more than one loading site is proposed, individual tables must be completed for each site.
C.2 Characteristics and Composition of the Substance or Material for Disposal Give particulars of the nature, composition and quantity of the substance or material to be disposed.
At a minimum, sampling must be conducted for the physical and chemical parameters listed in Tables C.1 (I) and (II), located in Annex 1 to this application form. Details of all sampling results of the substance or material to be disposed should be supplied via Tables C.1(I) and (II).
Applicants must also address the following criteria relating to the composition of the substance or material to be disposed: Amount and composition of the material; Material form, e.g., solid, liquid; For inspection purposes only. Physical properties (especiallyConsent solubility, of copyright specificowner required gravity for any other and use. density); Chemical and biochemical properties (e.g., oxygen demand, nutrients); Biological properties (viruses, bacteria, yeasts, parasites); Radioactivity; Toxicity; Persistence in the environment (physical, chemical and biological); Accumulation and biotransformation in biological materials or sediments; Chemical and physical changes of the substance or material after release, including formation of new compounds; Probability of production of taints or other changes reducing marketability of resources (e.g., fish, shellfish).
A report on the characteristics and composition of the substance or material for disposal should be submitted, addressing all criteria listed above, and any supporting information, as Attachment C.2.
Attachment C.2 included Yes No
*
* Under the OSPAR (1998) Guidelines for the Management of Dredged Material (Reference 1998-20) previously undisturbed geological material is exempt from detailed characterisation which includes chemical and biological.
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The Marine Institute and the EPA (email 3/05/2012 – CDM Smith reference 75461/CI974) and the Radiological Protection Institute of Ireland (RPII) (email dated 17/08/2012 – CDM Smith reference 75461/CI1149) were consulted with, and it was confirmed that testing of the limestone material to determine its chemical and biological nature would not be necessary as the limestone is an inert material of natural origin and does not consist of constituents likely to be released into the environment.
It was also determined through discussions with the Marine Institute (email dated 17/08/2012 – CDM Smith reference 75461/CI1151) and the RPII) (email dated 22/08/2012 – CDM Smith reference 75461/CI1152) , that the marine sediment from the drilling of the diffuser shaft would not require materials analysis, given the relatively small quantity (ca. 1,000 m3) and given its close proximity to the spoil disposal area at Burford Bank where it is proposed to redeposit it.
Further details are contained in Attachment 3: Dumping at Sea Permit Application Supporting Information Report.
For inspection purposes only. Consent of copyright owner required for any other use.
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SECTION D: IMPACT ON THE RECEIVING ENVIRONMENT Advice on completing this section is provided in the accompanying Guidance Note.
D.1. Assessment of Impact on the Environment
Provide an assessment of the predicted impacts of the proposed dumping at sea to which this application relates. This assessment should include the following, where applicable: Initial dilution to be achieved by proposed method of release; Methods of packaging and containment, if any; Dispersal, horizontal transport and vertical mixing characteristics; Existence and impact of current and/or previous dumping in the area (including accumulative effects); Sea bottom characteristics, including topography, geochemical and geological characteristics and benthic micro-fauna and macro-fauna; Water characteristics (e.g., temperature, pH, salinity, oxygen indices of pollution- dissolved oxygen (DO), nitrate, nitrite, ammonia, phosphate and suspended matter); Interference with shipping, fishing, recreation, mineral extraction, desalination, fish spawning and nursery habitats, areas of special scientific importance, areas of natural or archaeological heritage importance, biological diversity (including diversity within species, between species, and of ecosystems) and other legitimate use of the sea.
Details of any previous sampling at the loading and dumping sites, conducted either as part of this application or previous post-dumping monitoring programmes, should be supplied via Tables D.1(I) and (II). If sampling has been conducted as part of an EIS which has also been submitted with the application form, reference to the appropriate table(s) of results in the EIS will be sufficient in this case. Results of the National Seabed Survey should be included, where available.
Describe the existing environment at the loading and dumping sites in terms of water quality and sediment quality, with particular reference to environmental quality standards or other legislative standards.
Give details of any designation s under For inspection any purposes Council only. Directive or Regulations that apply in Consent of copyright owner required for any other use. relation to the loading and dumping sites. Indicate whether or not the loading and disposal of the substance or material, the dumping methods employed, or other factors associated with such operations are likely to have a significant effect on a designated site.
Any site which may have an impact on a Natura 2000 site (SPA or SAC) must be subject to screening for Appropriate Assessment in accordance with Article 6(3) of the Habitats Directive (92/43/EEC). The results of any such screening must be submitted as part of this application. Where screening has determined that an appropriate assessment is required, an appropriate assessment must be completed and a copy of said assessment submitted as part of this application. Please refer to the National Parks and Wildlife Service guidance document ‘Appropriate Assessment of Plans and Projects in Ireland’ with regard to this assessment.
This section should also contain full details of any modelling of the proposed loading and dumping operations.
Full details of the assessment and any other relevant information on the receiving environment should be submitted as Attachment D.1.
Attachment D.1 included Yes No
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SECTION E: DUMPING OPERATIONS
Advice on completing this section is provided in the accompanying Guidance Note.
E.1 Site Selection Provide details of the site selection process, including site description, suitability and rationale for final site selection. Full details of the site selection process should be submitted as Attachment E.1
Attachment E.1 included Yes No
E.2 General Information Provide information on the following points in the spaces provided.
E.2 (I) Has the proposed dump site(s) been used previously for disposal of material from the current proposed loading area(s) or any other loading area(s)? If so, provide details of tonnages/volumes, duration and any investigations into the impact of the dumping operations on the environment at the dump site(s). Please provide details of any previous permits relating to dumping operations at the site(s), if applicable.
Attachment E.2(I) included Yes No
E.2 (II) Dump site – four sets of coordinates must be given in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84). If dumping is to occur at more than one location, coordinates for additional areas should be appended.
Latitude Longitude ITM For inspection purposes only. (a) 53° 20′ 5′′ -6°Consent 3′ 3′′ of copyright owner required for any other use. E729824, N733371
(b) 53° 20′ 5′′ -6° 1′ 53′′ E731109, N733412 (c) 53° 19′ 11′′ -6° 1′ 52′′ E731170, N731750 (d) 53° 19′ 11′′ -6° 2′ 46′′ E730180, N731714 (e) 53° 19′ 24′′ -6° 3′ 3′′ E729855, N732102
Attachment E.2(II) Any associated drawings / maps should also be provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84).
Attachment E.2(II) included Yes No
E.2 (III) Name and address of disposal operator contracted to carry out the dumping (if known) Name: Unknown – Subject to tender Address:
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Tel: Fax: e-mail:
E.2 (IV) Distance of dump site from the nearest shore.
The nearest shore is Baily at Howth which is approximately 3 km away from the dump site at its closest point.
E.2 (V) Provide details of the average, minimum and maximum depth of the dump site(s) (to chart datum). For the Ringsend WwTW Extension Project a bathymetric survey was carried out in the Dublin Bay area using a multibeam echo sounder between October and December 2010.
Within the spoil disposal area marked on the Admiralty Chart the bathymetry data shows that the depth of the seabed ranges from 12.5 to 24 m chart datum (CD). The average depth was estimated to be 19 m CD.
E.2 (VI) Provide details of the method and rate of disposal (i.e. tonnes and cubic meters per day/week/month) of substance or material from the vessel.
The disposal methodology will likely be using a self propelled spilt bottom barge, where the hull of the whole barge splits longitudinally between the end bulkheads. The exact specifications of the vessel to be used will be dependent on the outcome of the tendering process. It is estimated that a typical load would be approximately 1,000 m3 and disposal at sea is likely to occur on average less than once per day and no more than twice per day, for a period of up to 3 years (2014-2017).
For inspection purposes only. Full discussion of method and rate ofConsent disposal of copyright is ownercontained required for inany theother use.attached DCC Dumping at Sea Permit Application Supporting Information Report - Section 5.3.
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SECTION F: MONITORING Advice on completing this section is provided in the accompanying Guidance Note.
F.1. Monitoring Programme
Proposed programmes for environmental monitoring at both the loading and dumping sites should be submitted as part of the application. These programmes should be provided as Attachment F.1.
Reference should be made to the proposed location of monitoring points, sampling methods, analytical and quality control procedures, including equipment calibration, equipment maintenance and data recording/reporting procedures to be carried out in order to ensure accurate and reliable monitoring.
In determining the monitoring programme to be carried out, the nature, frequency and duration of dumping operations and, where relevant, the effects of intermittent dumping on the receiving environment should be considered.
Details of any accreditation or certification of analysis should be included.
Attachment F.1 should also contain any supporting information.
Attachment F.1 included Yes No
*
______
F.2. Tabular data on Monitoring Points
Applicants should submit the following information For inspection purposes for each only. proposed monitoring point: Consent of copyright owner required for any other use.
PT_CD LATITUDE LONGITUDE ITM Point Code n/a* n/a* n/a* (Referencing system outlined in guidance notes) An individual record (i.e., row) is required for each monitoring point. Acceptable file formats include Excel, Access or other upon agreement with the Agency.
* As there is no dredging taking place no monitoring of the loading sites are proposed. Monitoring of the Dumping site is proposed: Bathymetric surveys and a Dumping Activity Log of the dumping site and is detailed in Attachment 3: Dumping at Sea Permit Application Supporting Information Report.
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SECTION G: DECLARATION
Declaration
I hereby apply for a Dumping at Sea permit, pursuant to the provisions of the Dumping at Sea Acts, 1996 to 2010.
I certify that the information given in this application is truthful, accurate and complete.
I give consent to the EPA to copy this application for its own use and to make it available for inspection and copying by the public, both in the form of paper files available for inspection at EPA and local authority offices, and via the EPA's website.
This consent relates to this application itself and to any further information or submission, whether provided by me as Applicant, any person acting on the Applicant’s behalf, or any other person.
Signed by: Date:______(on behalf of the organisation)
Print signature name:
Position in organisation:
For inspection purposes only. Consent of copyright owner required for any other use.
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ANNEX 1: TABLES
Table C.1(I) Material Sampling – Physical Properties Sampling Date: Sampling location: (e.g., L1-1, L1-2…….) Substance Result Fine Fraction Conc. (<2mm)Note 1: <63µm: % Solids Units of Measurement Density/Specific Gravity TOC Note 1: to be expressed as a percentage of total sample.
Table C.1(II) Material Sampling – Chemical Composition Sampling Date: Sampling location: (e.g., L1-1, L1-2…….) Substance Units of Measurement Result Arsenic Copper Cadmium Chromium Lead Mercury Nickel Zinc Aluminium Lithium Organochlorine Pesticides Tributyltin (TBT) Note 1 Note 1 For inspection purposes only. Dibutyltin (DBT) Consent of copyright owner required for any other use. PCBs Note 1 PAHs Note 1 Total Extractable Hydrocarbons Note 1: Only determined in certain circumstances – see Application Guidance Note for further information.
Table D.1(I) Receiving Environment Sampling – Physical Properties Sampling Date: Sampling location: (e.g., D1-1, D1-2…….) Substance Result Fine Fraction Conc. (<2mm)Note 1: <63µm % Solids Units of Measurement Density/Specific Gravity TOC Note 1: to be expressed as a percentage of total sample.
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Table D.1(II) Receiving Environment Sampling – Chemical Composition Sampling Date: Sampling location: (e.g., D1-1, D1-2…….) Substance Units of Measurement Result Total Organic Nitrogen Arsenic Copper Cadmium Chromium Lead Mercury Nickel Zinc Aluminium Lithium Organochlorine Pesticides Tributyltin (TBT) Note 1 Dibutyltin (DBT) Note 1 PCBs Note 1 PAHs Note 1 Total Extractable Hydrocarbons Note 1: Only determined in certain circumstances – see Application Guidance Note for further information.
For inspection purposes only. Consent of copyright owner required for any other use.
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ANNEX 2: APPLICATION CHECKLIST
This checklist is to assist the applicant in ensuring a valid and complete application is submitted to the Agency. Checked by Checked Section of Application Form Applicant by Agency A.2 Planning Permission / EIS attached Yes
A.3(i) SFADCo. correspondence attached n/a*
A.3(iii) Harbour Authority notice attached Yes
A.4 Original newspaper notice included No
A.5 Appropriate fee paid Yes
A.6 Foreshore Licence attached No*
A.7 Current / previous permit attached Yes
B.1 Alternative measures investigation attached Yes
B.2 Purpose of the operation attached Yes
B.3 Loading location maps / drawings attached Yes
B.4 Operational details attached Yes
C.1 Material analysis report attached Yes*
D.1 Assessment of impact on the environment attached Yes
E.1 Site selection report attached For inspection purposes only. Yes Consent of copyright owner required for any other use.
E.2(II) Dump site maps / drawings attached Yes
F.1 Correspondence from Marine Survey Office attached No – Details of marine position recording equipment vessel is subject F.2 to tender attached G.1 Programme for environmental monitoring attached Yes*
Additional Checks All drawings / maps provided as geo-referenced digital drawing files (e.g. ESRI Shapefile, MapInfo Tab or other upon agreement) Yes in both 12-digit Irish Transverse Mercator (ITM) and in Longitude and Latitude (WGS 84) 1 signed original application form (with attachments). Yes 1 additional application hardcopy. Yes 2 copies of all files in electronic searchable PDF format on CD_ROM Yes (OCR’d) or other agreed format.
* Please refer to comments in previous sections for explanations regarding attachments.
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Attachments Table of Contents
Attachment 1 A.2 Planning Permission
Attachment 2 A.3 (iii) Harbour Authority Notice
Attachment 3 A.7 Details of Current/Previous Permits
Attachment 4 Dumping at Sea Permit Application Supporting Information Report Contains attachment for Sections B to F of the Application Form. Appendices include:
Appendix A Figures and Drawings Figure A.1 Loading Area (Ref B.3) Figure A.2 Diffuser Shaft Loading Area (Ref B.3) Figure A.3 Location of Spoil Disposal Area (Ref E.2 (II)) Figure A.4 Bathymetry of Spoil Disposal Area (E.2 (V))
Appendix B Tunnel Spoil Disposal Study 2011 Appendix C Calculations for Fuel consumption and
Estimated CO2 emissions Appendix D DHI Marine Survey Report 2010 Appendix E Estimated Particle Size Distribution and Calculation of Sinking Velocities Appendix F Screening for Appropriate Assessment
Ringsend WwTW Extension Project Environmental Impact Statement (A.2)
Volume 1 Environmental Impact Statement
Volume 2 Appendices Part 1 For inspection purposes only. Consent of copyright owner required for any other use.
Volume 2 Appendices Part 2
EPA Export 10-12-2012:23:36:42 An Bord Pleanála
PLANNING AND DEVELOPMENT ACTS 2000 to 2011
An Bord Pleanála Reference Number: 29N.YA0010
Dublin City Council
APPLICATION by Dublin City Council for approval under section 226 of the Planning and Development Act 2000, as amended, in accordance with plans and particulars, including an Environmental Impact Statement and Natura Impact Statement, lodged with the Board on the 13th day of April, 2012.
PROPOSED DEVELOPMENT: Ringsend Wastewater Treatment Works Extension Project which will expand the existing wastewater treatment works at Pigeon House Road, Ringsend, Dublin to its ultimate capacity within the confines of its current site and achieve the required discharge standards. The proposed extension includes the following elements of works:
For inspection purposes only. • Additional secondary Consentwastewater of copyright treatment owner required forcapacity any other use. at the wastewater treatment works site (approximately 400,000 population equivalent) including associated solids handling and ancillary works.
• A 9 kilometre Long Sea Outfall (in tunnel), commencing at an onshore inlet shaft approximately 350 metres east of the wastewater treatment works and terminating in an underwater outlet riser/diffuser in Dublin Bay.
• Road network improvements in the vicinity of the site (during the construction phase).
DECISION
GRANT approval for the above proposed development in accordance with the said plans and particulars based on the reasons and considerations under and subject to the conditions set out below.
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MATTERS CONSIDERED
In making its decision, the Board had regard to those matters to which, by virtue of the Planning and Development Acts and Regulations made thereunder, it was required to have regard. Such matters included any submissions and observations received by it in accordance with statutory provisions.
REASONS AND CONSIDERATIONS
In coming to its decision, the Board had regard to the following:
(a) The discharge standards set out in the Water Framework Directive (2000/60/EC), the Urban Wastewater Treatment Regulations (SI 254 of 2001), the Bathing Water Regulations (SI 79 of 2008) and the Surface Water Regulations (SI 272 of 2009).
(b) The discharge licence granted by the Environmental Protection Agency to Ringsend Wastewater Treatment Plant under licence number (D00-34-01) and the Emission Limit Values therein.
(c) The current performance of the existing wastewater treatment plant and the need to improve discharge standards from same, to meet water quality standards for bathing waters, coastal waters, transitional waters and designated sensitive waters in Dublin Bay in accordance with the requirements set out under the Water Framework Directive (2000/60/EC).
(d) The policies, provisions and For objectivesinspection purposes set only. out in the Greater Dublin Strategic Consent of copyright owner required for any other use. Drainage Study, 2005, the Regional Planning Guidelines for the Greater Dublin Area 2010-2022 and the Dublin City Development Plan 2011-2017, all of which have an objective to expand the existing wastewater treatment facility at Ringsend to its ultimate capacity, as well as the provision for another regional plant.
(e) The demonstrated need for increased capacity at this location, notwithstanding being part of an overall programme for increasing sewerage capacity in the Greater Dublin Area.
(f) The site’s location on the Poolbeg Peninsula, remote from residential development and the pattern of development in the vicinity of the site.
(g) The nature, scale and design of the proposed development.
(h) The documents, including the environmental impact statement and natura impact statement accompanying the application, and the submissions on file generally, which the Inspector and the Board examined, analysed and evaluated.
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(i) The objections made to the proposed development.
(j) The report of the Inspector, who held the oral hearing.
The Board conducted an Environment Impact Assessment and concluded that, subject to compliance with the conditions set out below, the proposed development would not adversely impact upon the environment. The Board considered that the proposed development would be likely to enhance the quality of water in Dublin Bay, which in turn, would improve its amenity value and ecology.
The Board completed an Appropriate Assessment of potential impacts of the proposed development on the South Dublin Bay and River Tolka Estuary Special Protection Area, the North Bull Island Special Protection Area, the Howth Head Coast Special Protection Area, the South Dublin Bay Special Area of Conservation, the North Dublin Bay Special Area of Conservation and the Howth Head Special Area of Conservation and other nearby European sites. Taking into account the natura impact statement submitted and the Inspector’s assessment, the Board concluded that, on the basis of the information available, the proposed development, either individually or in combination with other plans or projects, would not adversely impact on the integrity of designated Natura 2000 Sites in Dublin Bay in view of the conservation objectives for the site.
The proposed development would facilitate the planned growth of the Greater Dublin Area. It is considered that, subject to compliance with the conditions set out below, the proposed development would not seriously injure the amenities of the area or of property in the vicinity, would be acceptable in terms of traffic, noise, odour and water quality, and would, therefore, be in accordance with the proper planning and sustainable development of the area.
For inspection purposes only. Consent of copyright owner required for any other use.
CONDITIONS
General
1. The development shall be carried out and completed in accordance with the plans and particulars lodged with the application and the information contained in the environmental impact statement, including all mitigation measures contained therein, as amended by the further plans and particulars submitted at the oral hearing, except as may otherwise be required in order to comply with the following conditions.
Reason: In the interest of clarity.
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Operation
2. The proposed development shall be constructed to a standard capable of complying with the following treated maximum effluent values:
Biochemical Oxygen Demand – 25mg/l Total Suspended Solids – 35 mg/l
Reason: In the interest of clarity and to comply with the requirements of the Urban Wastewater Treatment Regulations (S.I. No. 254 of 2001).
2 3. The odour emanating from the site shall not exceed 10 OU E/mg at the 98 percentile for hourly averages for more than 50 hours per year at the site boundary.
Reason: In the interest of the amenities of the surrounding area.
4. Dust levels at the site boundary shall not exceed 350 mg/m2/day averaged over a continuous period of 30 days. A monthly survey and monitoring programme of dust and particulate emissions shall be undertaken to provide for compliance with these limits.
Reason: To control dust emissions arising from the development and in the interest of the amenities of the area.
For inspection purposes only. Consent of copyright owner required for any other use. Construction Phase
5. A construction stage environmental management plan (CSEMP), including all construction method statements, shall be prepared by the developer and implemented by the contractor. The developer shall retain responsibility for overseeing, updating and enforcing the construction environmental management plan. The construction environmental management plan shall adhere to the following requirements:
(a) All preventative and management measures to be applied throughout the construction phase shall be set out so that all potential impacts are minimised, mitigated, or avoided.
(b) All measures to be employed in relation to spill contingencies, spoil disposal, management of contaminated soil, the selection of slurry additives and drilling fluids.
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(c) Measures set out in the Construction Industry Research and Information Association (CIRIA) on the control and management of water pollution from construction sites shall be adhered to.
(d) All fuels or chemicals kept on the construction site shall be stored in bunded containers. All refuelling and maintenance of vehicles and equipment shall be carried out in designated containment areas away from sensitive environments.
(e) Any waste or hazardous waste residuals or potentially contaminated sludge from spill clean-up shall be stored in appropriate receptacles or containers, or in bunded storage areas prior to their removal by the developer or EPA licenced contractor.
(f) Any discharges arising from the construction phase shall incorporate silt removal and hydrocarbon removal using a hydrocarbon interceptor.
(g) Weekly monitoring of the water quality being discharged off the site shall take place during the construction phase.
(h) Foul sewage shall be transported off site and disposed of by discharging to a licenced sewer network.
(i) All marine vessel waste generated during the pipeline survey, and any maintenance vessels including marine rigs, shall accord with relevant guidelines including those guidelines from Annex V of the International Convention for the Prevention of Pollution from Ships, as amended. All
hazardous waste stored For inspectionon ships purposes shallonly. be contained in sealed labelled Consent of copyright owner required for any other use. containers and stored in lockable container cabinets. A record of all types and quantities of waste arising on each vessel shall be kept.
(j) The Guidelines entitled ‘Requirements for the Protection of Fisheries Habitats during Construction and Development Works at River Sites’ prepared by the Eastern Regional Fisheries Board shall be adhered to in full.
(k) Management proposals and monitoring protocols for areas of ecology, archaeology, water quality management (both ground and surface), dust management, noise management, traffic management, sediment control, spoil disposal, general pollution control, community liaison, hazardous substance management, environmental training and supervision for personnel.
(l) Details of the management of all landscaping within the sites and, where appropriate, in the vicinity of the site.
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(m) Details of site managers, contact numbers (including out of hours) and public information signs (including warning signs) at the entrance and, where appropriate, at the boundaries of the site.
(n) Details of a pest control plan.
(o) Staff parking shall not be permitted in the public car park in the vicinity of the site and suitable car parking places shall be provided elsewhere.
Upon the commencement of construction, the CSEMP will be reviewed according to a regular timeframe and will be updated if necessary. Environmental auditing will be undertaken to ensure compliance with the CSEMP.
Reason: In the interest of the protection of the environment during the construction phase.
6. Where blasting is to take place during the construction works for both the inlet tunnel shaft, or in the case of the wastewater treatment works extension, ground vibrations shall not exceed twelve millimetres per second peak particle velocity (when measured in any one of the three mutually orthogonal plains) for any blast when measured at the nearest vibration sensitive location. If blasting occurs more than once a week, ground vibration shall not exceed eight millimetres per second peak particle velocity (when measured in any one of three mutually orthogonal plains) for any blast when measured at the nearest vibration sensitive location.
The air over-pressure from any blast shall not exceed the value of 125 B(lin)
maximum peak with a 95% For confidence. inspection purposes only.No individual air over pressure value Consent of copyright owner required for any other use. shall exceed the limit value by more than 5 dB (Lin).
A monitoring programme, which shall include reviews to be undertaken at monthly intervals, shall be developed to assess the impact of the blasts.
Reason: In the interest of public safety and residential amenity.
7. Underwater noise levels shall be monitored in accordance with a monitoring plan drawn up following consultation with the National Parks and Wildlife Service during the construction period.
Reason: To ensure the protection of marine mammals and other marine fauna.
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8. During the construction of the diffuser shaft, a suitably qualified marine ecologist shall be present on the marine construction rig so as to ensure that no cetaceans are within the 100 meter exclusion zone of the rig during the commencement of drilling operations. Where such marine fauna are present within the exclusion zone, drilling operation will be suspended until such time as the fauna leave the exclusion zone.
Reason: To ensure the protection of cetaceans.
9. Appropriate reinstatement of all landscaping, earthworks, boundaries and access arrangements shall take place following construction phase and a landscaping scheme implemented in the first planting season following completion of works. Works shall include the dismantling of all temporary construction works and removal of all equipment and other temporary infrastructure on site.
Reason: In the interest of visual amenity.
10. A comprehensive method statement relating to the installation of the underground electricity supply cables and road improvement works shall be prepared prior to the commencement of works. Works on the existing compensatory grassland shall not be undertaken during the winter period (September 1st to April 30th inclusive).
Reason: In the interest of orderly development and to ensure that the potential impact on the Brent Geese using the grassland is minimised.
For inspection purposes only. Consent of copyright owner required for any other use.
11. All works to be undertaken within and adjacent to Natura 2000 Sites within Dublin Bay will be undertaken in accordance with the requirements of a suitably qualified ecologist appointed following consultation with the National Parks and Wildlife Service.
Reason: In the interest of ecological protection.
12. The developer shall participate in the detailed monitoring of bird species and bird numbers together with their distribution within the Dublin Bay Area over the next six year period from the date of this order. Details of the exact nature and composition of the surveys shall be agreed in consultation with the National Parks and Wildlife Service.
Reason: To add to the scientific knowledge of the ecology of Dublin Bay.
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13. A clearly demarcated pedestrian crossing on Pigeon House Road to the east of the wastewater treatment plant, together with the construction of a railing along the footpath on the northern side of the Pigeon House Road and a slip form kerb barrier, shall be provided along the southern side of Pigeon House Road and shall be constructed prior to commencement of development. Access arrangements for pedestrians shall be monitored on a weekly basis throughout the construction period. Where it is decided that pedestrian access arrangements to the South Bull Wall and surrounding amenity area are adversely affected during the construction period, appropriate measures shall be incorporated to minimise any impact on pedestrian access arrangements.
Reason: In the interest of pedestrian safety.
14. The developer shall facilitate the preservation, recording and protection of archaeological materials or features that may exist within the construction sites, and the area of land affected by the laying of electric cables, the proposed new access slip road on land and the protection of any marine archaeological deposits that may exist in the vicinity of the proposed diffuser shaft. In this regard the developer shall:
(a) Notify the Department of the Environment Community and Local Government in writing at least four weeks prior to the commencement of any site operations (including hydrological and geotechnical investigations) relating to the proposed development.
(b) Employ a suitably qualified archaeologist who shall monitor all site
investigations and other For excavation inspection purposes works. only. Consent of copyright owner required for any other use.
(c) Provide arrangements for the recording and for the removal of any archaeological material which the Department of the Environment Community and Local Government considers appropriate to remove.
In default of an agreement on any of these requirements, the matter shall be referred to An Bord Pleanála for determination.
Reason: In order to conserve the archaeological heritage of the site and to secure the preservation and protection of any remains that may exist within the site.
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15. An archaeological dive inspection shall take place prior to commencement of works in order to clarify the nature of the anomalies identified during the off- shore investigations on the sea bed. If required, the diffuser shaft shall be relocated to a point as close as possible to the proposed location without impinging or impacting upon any feature of archaeological interest. All such works shall be carried out in consultation and under the supervision of a suitably qualified marine archaeologist.
Reason: In order to conserve the archaeological heritage of the bay and to secure the preservation and protection of any remains that may exist within the bay.
16. The developer shall inform Dublin Port Authority of the precise location, including the geographical co-ordinates, of the tunnel and the outfall diffuser shaft. The location of the diffuser shaft, as constructed, shall be clearly and accurately marked on a revised Dublin Admiralty Chart.
Reason: To ensure that the diffuser shaft and outfall tunnel can be accurately located and identified, to notify marine traffic.
For inspection purposes only. Consent of copyright owner required for any other use.
______
Member of An Bord Pleanála duly authorised to authenticate the seal of the Board.
Dated this day of 2012.
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EPA Export 10-12-2012:23:36:42
O’Connell Bridge House, 5th Floor D’Olier St, Dublin 2, Ireland tel: +353 1 672 2700 fax: +353 1 672 4744
Date: 27 September 2012
Captain David Dignam Harbour Master Dublin Port Company, Port Centre, Alexandra Road, Dublin 1
Subject: Dublin City Council intention to submit an application to the EPA for a Dumping at Sea Permit
Dear Capt. Dignam,
As per our previous discussions, we are writing to inform you that Dublin City Council intend to submit an application to the Environmental Protection Agency for a permit, under Section 5 of the Dumping at Sea Acts 1996 to 2010.
The application is for a proposal of a maximum of 950,000 tonnes of spoil from the tunnelling of the long sea outfall for the extension to Ringsend Wastewater Treatment Works. The spoil will consist of 99.8 % (by weight) crushed rock, and 0.2 % marine sediments (clay, gravel and sand). The proposed marine disposal site is the designated Burford Bank spoil disposal area located For inspection purposes only. approximately is 3 km from BailyConsent at ofHowth copyright atowner its required closest for any point. other use. It is proposed that the disposal operation will take place between January 2014 and August 2017 – at an average rate of no more than 1 barge per day with an occasional maximum up to 2 barges per day. The tunnel excavation operations will be undertaken from the onshore tunnel inlet shaft where the tunnel boring machine will be launched. A split bottom barge will be used to dispose of the material.
Please do not hesitate to contact the undersigned should you require any further information.
Yours sincerely,
Mr. Anthony G. Kerr Technical Director CDM Smith Ireland Limited.
cc. Owen McManus, Dublin City Council
CDM Smith Ireland Limited Directors: A G Hooper (Managing), H Kroll (Germany), R C Johnson (USA) Registered in Ireland: 338589 Registered Office: O’Connell Bridge House, 5th Floor, D’Olier Street, Dublin 2
EPA Export 10-12-2012:23:36:42 For inspection purposes only. Consent of copyright owner required for any other use.
EPA Export 10-12-2012:23:36:42 1. The Minister for Food, in exercise of the powers conferred on him by section 5 ofthe Dumping at Sea 1996 (No. 14 of 1996), and consultation with the Minister for the Environment, Heritage and Local Government and Minister for and Employment hereby permit to Dublin Council, Civic Offices, Wood Quay, Dublin 8
2. There is hereby authorised by this permit:-
loading at Macken Street onto the SAND" during the period 2nd June 2009, to 31,1 October 2009 of up to 25 tonnes daily of spoil up to a maximum total 0[300 tonnes.
(b) The dumping from "HEBBLE SAND" that of sea bounded by
(i) latitude 53 020,07' and longitude 06°03 .00',
(ii) latitude 53 "20.01' and longitude 06°01 For inspection purposes only. Consent of copyright owner required for any other use. (iii) latitude 53°19.17' and longitude 06°01.82')
(iv) latitude and longitude 06°02.71 ';
(v) latitude 53"] 9.38' longitude 06"03.00',
during period from June 2009, to 31 st October 2009 of up to 25 tonnes daily of dredge up to a maximum total of 300 tonnes.
3. pennit is granted upon and subject to the following conditions:-
EPA Export 10-12-2012:23:36:42 (a) Dumping shall be effected by release through the hull of the vessel while the vessel is in motioo.
(b) The following infonnation in relation to each load of the substance or material intended to be dumped, and put on board the vessel, shall be entered in a register relating to the dumping wh.ich shall be maintained by the holder of the pennie
(i) the name of the vessel;
(ii) the source of the substance or material;
(iii) the date, time and position at which the voyage for the purposes of dumping began and the place at which it began (in lat. / long.);
(iv) the date, time and position at which dumping began (in lat. / long.);
(v) the date, time and position at which dumping ended (in lat. / long.);
(vi) the quantity, stated in metric tonnes, of the substance or material dumped;
(vii) the date, time and pOSItIon at which the vessel completed the voyage for the purpose of dumping and the place at which it was completed (in lat. / long.).
(c) Entries in a register or log required to be made pursuant to this permit shall be made as soon as may be after the events to which they relate. The
register or log shall For be inspection retained purposes foronly. not less than three years after the Consent of copyright owner required for any other use. making of the entries and copies of any such entries made during the period of validity of this permit shall be sent to the Minister for Agriculture, Fisheries and Food, Clogheen, Clonakilty, Co Cork as soon as possible after 1st November, 2009.
(d) The cost of any other tests, sampling, analysis and monitoring which the Minister for Agriculture) Fisheries and Food may require in relation to the dumping of the substance or material the subject of this permit shall be borne by the pennit holder. Furtheonore, the cost of any tests, sampling, analysis and monitoring surveys carried out by an authOIised officer or by or on behalf of the Minister for Agriculture, Fisheries and Food in relation to the dumping of a substance or material the subject of this permit shall also be borne by the holder of the permit.
(e) The master and owner of the vessel shall, if so requested, permit an authorised officer to be on board the vessel during dumping operations.
EPA Export 10-12-2012:23:36:42 They shall pennit and facilitate the carrying out by the officer of his functions under the Dumping at Sea Act, 1996 as amended, and shall comply with the provisions of that Act i!l relCltion to the officer and those functions.
(f) A marine position recorder in accordance with Department of Agriculture, Fisheries and Food specifications shall be commissioned and maintained on the dumping vessel. Infonnation regarding dumping voyages shall be automatically recorded to allow monitoring of the dumping operation by the Department of Agriculture, Fisheries and Food on a regular basis.
(g) Dublin City Council shall adhere to the recOlmnendations made by the Department of the Environment, Heritage and Local Goverrunent in connection with marine archaeology and shall liaise with the Underwater Archaeology Unit in this regard. Archaeological monitoring must be undertaken when the dredging phase of the existing project gets underway, and be carried out under licence to the Dept. of Environment, by a suitably qualified archaeologist with underwater Imaritime experience.
(h) The disposal site at sea and associated dispersal plume shall not intersect established salmonoid migratory pathways and feeding zones.
(i) All vessels used in connection with the dredging and dumping activity that is the subject of this pennit must meet with the requirements of the Marine Surveyors Office for the purposes stated in this penuit.
(j) Dumping operations For of inspection the contaminated purposes only. spoil shall be carried out within 3 Consent of copyright owner required for any other use. days either side of neap tides, wherever feasible.
(k) Dumping of contaminated spoil shall be camed out at slack water only.
(l) Dumping of contaminated spoil shall take place as close to the seabed as possible, in order to reduce the winnow and other effects of high water content of material.
(m) Dublin City Council shall indemnify and keep indenmified the State, the Minister for Agriculture, Fisheries and Food, his officers, servants or agents against all actions, loss) damage, costs, expenses and any demands or claims howsoever arising in connection with the dredging and disposal operations that are the subject of this permit, and Dublin City Council shall take such steps as the Minister may specify in order to ensure compliance with this condition.
EPA Export 10-12-2012:23:36:42 An officer of the Department of Agriculture, Fisheries and Food duly authorised by the Minister for Agriculture, Fishelies and Food under Section 15(4) of the Ministers and Secretaries Act, 1924, to authenticate pennits under section 3 of the Dumping at Sea Act, 1996 as amended.
~ . Dated this ~ day of June 2009
Signed on behalf of holder of permit
Date:
This permit may be amended or revoked by the Minister for Agriculture, Fisheries and Food whenever he thinks it appropriate to do so. Breach of a condition of this permit will render the permit holder, the master and the owner of the vessel concerned, and any other person who causes or pennits dumping or loading for dumping in pursuance of this permit, liable to prosecution for unlawful dumping or loading for dumping, as the casc maybe. For inspection purposes only. Consent of copyright owner required for any other use.
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Ringsend Wastewater Treatment Works Extension Project
Ringsend WwTW Effluent Outfall Extension Dumping at Sea Permit Application Supporting Information
For inspection purposes only. Consent of copyright owner required for any other use.
Final 01
November 2012
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For inspection purposes only. Consent of copyright owner required for any other use.
EPA Export 10-12-2012:23:36:42 Ringsend WwTW Extension Project • DCC Dumping at Sea Permit Application Supporting Information
Document Control Sheet
Client Dublin City Council Project Ringsend Wastewater Treatment Works Extension Project No: 75461 Report Dumping at Sea Permit – Application Supporting Information Document Reference: 75461/DG91 Version Author Checked Reviewed Date A Kerr 27 September Draft 01 L Gaston D Keating B Gaudes 2012 Final 01 L Gaston D Keating A Kerr 26 November 2012
Distribution Copy No.
For inspection purposes only. Consent of copyright owner required for any other use.
75451/ DG91 – Final 01 – Nov 2012
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EPA Export 10-12-2012:23:36:42 Ringsend WwTW Extension Project • DCC Dumping at Sea Permit Application Supporting Information
Table of Contents
Section 1 Introduction ...... 1 1.1 Dumping at Sea Permit ...... 1 1.2 Project Background...... 2 1.2.1 Long Sea Outfall Tunnel ...... 2 1.2.2 Design Build ...... 6 Section 2 Loading Operations (Section B) ...... 7 2.1 Alternative Measures (B.1) ...... 7 2.1.1 Summary of Alternative Disposal Options Investigated ...... 7 2.1.2 Discussion of Land Recovery (Quarry Restoration) Verses Sea Disposal Options ...... 10 2.1.3 Steps to be Taken to Render the Material Less Harmful ...... 12 2.2 Purpose of the Operation (B.2)...... 13 2.3 Details of the Loading Operation (B.3 and B.4) ...... 13 2.3.1 Date of Commencement of Loading Operations (B.4 (I)) ...... 13 2.3.2 Location and Method of Loading (B.4 (II)) ...... 13 2.3.3 Calculations of Predicted Spoil Volumes (B.4 (IV)) ...... 14 Section 3 Material Analysis (Section C) ...... 16 3.1 Characteristics and Composition of the Substance or Material for Disposal (C.2) ...... 16 3.1.1 Background to Marine Site Investigations...... 16 3.1.2 Material Form and Physical Properties ...... 17 3.1.3 Chemical Properties ...... 18 Section 4 Impact on the Receiving Environment (Section D) ...... 20 4.1 Introduction ...... 20 4.2 Existing Environment ...... 20 4.2.1 Sea Bottom Characteristics ...... 20 4.2.2 Dispersal Characteristics Background Data ...... 21 4.2.3 Water Characteristics ...... For inspection purposes...... only...... 27 Consent of copyright owner required for any other use. 4.2.4 Flora and Fauna ...... 29 4.3 Assessment of Potential Impact ...... 32 4.3.1 Dilution and Dispersal Characteristics ...... 32 4.3.2 Cumulative Effects of Current and/or Previous Dumping in the Area ...... 34 4.3.3 Potential Impacts on Ecology ...... 34 4.3.4 Potential Impacts on Marine Uses and Resources ...... 36 Section 5 Dumping Operations (Section E) ...... 40 5.1 Site Selection (E.1) ...... 40 5.2 General Information about the Proposed Spoil Disposal Area (E.2) ...... 41 5.2.1 Details of Previous Dumping at the Site (E.2 (I)) ...... 41 5.3 Details of Method and Rate of Disposal (E.2 (VI)) ...... 41 Section 6 Monitoring (Section F) ...... 43 6.1 Bathymetry ...... 43 6.2 Dumping Activity Log ...... 43 Section 7 Summary ...... 44 Section 8 References ...... 45
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List of Figures
Figure 1 Location of existing and proposed discharge location in relation to the Water Framework Directive Water bodies ...... 3 Figure 2 Indicative cross section of the proposed tunnel ...... 5 Figure 3 Marine site investigation borehole locations ...... 16 Figure 4 Seabed characterisation of the spoil disposal area (reproduced from INFOMAR, 2010) ...... 21 Figure 5 Location of DHI marine survey area ...... 23 Figure 6 Example of presentation of current data (current rose) from station 1 ...... 24 Figure 7 Example of presentation of wave data (wave rose) from station 2...... 26 Figure 8 Water Quality Montiroing Loactions within Dublin Bay ...... 27 Figure 9 Behaviour of material during disposal (US EPA and USACE, 1998) ...... 32 Figure 10 Archaeological areas in the vicinity of Pigeon House Jetty (extract from Chapter 15 EIS) ...... 38 Figure 11 Constraints for site selection of spoil disposal area ...... 40
List of Tables
Table 1 Summary of alternative reuse, recovery and disposal options ...... 8
Table 2 Fuel consumption and estimated CO2 emissions ...... 12 Table 3 Estimate of spoil quantities from tunnelling works proposed for dumping at sea ...... 14 Table 4 Total quantities and rates to be loaded ...... 15 Table 5 Material composition (based on BS 1377-2:1990) ...... 17 Table 6 Tidal level in metres relative to Chart Datum (UKHO, 2012) ...... 22 Table 7 Summary of current data (Irish Hydrodata Ltd, 1995) ...... 22 Table 8 Wind data - Dublin Airport 1981–2010 ...... 24 Table 9 Summary of wave heights ...... 25 Table 10 Average (or Median) water quality results at “5 km ESE Poolbeg Lighthouse” from 2008-2009 ...... 27 Table 11 Dublin Bay TSAS Score (EPA, 2010) ...... For inspection purposes only...... 29 Consent of copyright owner required for any other use. Table 12 Natura 2000 Sites ...... 30 Table 13 Material composition – Upper and lower limit (based on BS 1377-2:1990) ...... 33
ii 75451/ DG91 – Final 01 – Nov 2012
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Appendices
Appendix A Figures and Drawings
Appendix B Tunnel Spoil Disposal Study 2011
Appendix C Calculations for Fuel consumption and Estimated CO2 emissions
Appendix D DHI Marine Survey Report 2010
Appendix E Estimated Particle Size Distribution and Calculation of Sinking Velocities
Appendix F Screening for Appropriate Assessment
For inspection purposes only. Consent of copyright owner required for any other use.
75451/ DG91 – Final 01 – Nov 2012 iii
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Section 1 Introduction
1.1 Dumping at Sea Permit Dublin City Council (DCC) intend to upgrade the Ringsend Wastewater Treatment Works (WwTW) to meet the future demand projected for the catchment area and to ensure compliance with relevant legislation. The plant is presently experiencing periodic loading in excess of capacity. The plant will be upgraded from its present capacity of 1.64 million population equivalents (PE) to an ultimate firm design capacity of 2.1 million PE.
The Ringsend WwTW Extension project includes the construction of a long sea outfall tunnel (LSOT) for treated final effluent. The LSOT will be tunnelled deep under the seabed in the underlying limestone bedrock. The tunnel itself is proposed to be approximately 9 km long with a finished internal diameter of approximately 5.0 m (6.5 m external diameter).
An Environmental Impact Statement for the entire Ringsend WwTW Extension Project was submitted to An Bord Pleanála (ABP) in April 2012. Planning permission was received from ABP on 16th September 2012 (ABP Ref: YA0010).
As a result of the tunnelling and associated shaft works, a large volume of excavated material (spoil) will be generated. The bulk of the spoil will be a clean inert material of natural origin. The spoil will be required to be transported from the construction compound site located on the Poolbeg Peninsula for reuse or disposal. In addition, a small proportion of the spoil from marine excavation of the diffuser shaft will also be required to be disposed of.
In 2011 various options for spoil disposal were investigated and disposal at sea was identified as a viable option. Under the Convention for the Protection of the Marine Environment of the North-East Atlantic (the “OSPAR Convention”) which entered into force in 1998, the dumping of inert materials of natural origin is permitted. This report provides a summary of the investigations of alternatives for the spoil disposal and an For inspection purposes only. assessment of the cost and environmentalConsent of benefits. copyright owner required for any other use.
This document supports Dublin City Council’s Dumping at Sea Application Form for the disposal of inert material of natural origin at the spoil ground within Dublin Bay and follows the EPA (2011) Dumping at Sea Permit Application Guidance Note.
The application form is divided into seven sections as follows:
. Section A: General
. Section B: Loading Operation
. Section C: Material Analysis
. Section D: Impact on the Receiving Environment
. Section E: Dumping Operations
. Section F: Monitoring
. Section G: Declaration
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Where possible, the report cross references with the relevant sections of the application form by indicating the Dumping at Sea Application Form reference in brackets after the section headings within this report. Note not all of the application form sections require supporting information and as such may not be addressed in this report. 1.2 Project Background The Ringsend WwTW Catchment includes Dublin City, Dun Laoghaire, large areas of South County Dublin and Fingal, and a small area of Meath. Ringsend WwTW is currently overloaded and by 2015, the earliest that the extended Works would be expected to be commissioned, the influent loading is projected to be between 1.90 million PE and 1.95 million PE, or between 116 % and 119 % of original design capacity. Deferring construction of the WwTW extension would only exacerbate the current overloading problem. Effluent quality can be expected to deteriorate until the upgraded facilities become operational.
Also the discharge effluent standards have become more stringent since the original plant was designed and constructed. The Liffey Estuary was designated as Nutrient Sensitive Waters in 2001, and as a consequence the EU Urban Waste Water Treatment (UWWT) Directive requires additional nutrient removal, in addition to normal secondary treatment standards, for continued discharge at the existing treated effluent outfall to the Liffey Estuary.
The Ringsend WwTW, as currently configured, has limited nutrient removal capacity. With open space on site extremely limited and with no ability to extend the WwTW’s boundaries, it is most unlikely that compliance with the UWWT total nitrogen limit at the design horizon loading could be accomplished with conventional wastewater treatment processes. Designation of the Liffey Estuary as Nutrient Sensitive Waters together with the space constraints has, prompted consideration of the option of moving the existing treated effluent outfall location (in the Liffey Estuary) to a point outside the Nutrient Sensitive designation, where additional discharge standards are not applied by any regulatory authorities.
1.2.1 Long Sea Outfall Tunnel The project includes the construction of a new long sea outfall tunnel (LSOT) to discharge the final treated effluent at an offshore location (Figure 1). The LSOT is proposed to originate at the eastern tip of the Poolbeg Peninsula in County Dublin. The LSOT will be tunnelled deep under the seabed in the underlying For inspection purposes only. limestone bedrock. The tunnel itself isConsent proposed of copyright to be owner approximately required for any other9 km use. long with a finished internal diameter of approximately 5.0 m (6.5 m external diameter).
The overall outfall tunnel consists of the following elements:
1. The onshore tunnel inlet shaft;
2. The tunnelled section; and
3. The offshore tunnel outlet diffuser riser shaft. The onshore tunnel inlet shaft An onshore tunnel inlet shaft will be constructed on the Poolbeg Peninsula on the ESB Poolbeg site. The estimated finished internal diameter of the tunnel inlet shaft is significantly larger than the tunnel itself and approximately 20 m in diameter but could potentially be smaller depending upon the eventual tunnelling construction technique adopted. Taking a conservative approach, the maximum total excavated external diameter is estimated to be 22.5 m. Based on a preliminary conceptual design, the tunnel inlet shaft invert is likely to be somewhere between 66 m and 110 m below existing ground level. The final selected depth will depend on a combination of the vertical alignment selected for the tunnel section and geotechnical design considerations made by the design and build contractor.
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The tunnel excavation operations will be undertaken from the onshore tunnel inlet shaft. The onshore tunnel inlet shaft will be used to service the tunnel with equipment and material requirements for the duration of the project. Spoil materials from tunnel construction will be brought to the surface through the onshore tunnel inlet shaft.
Note that only bedrock spoil from the inlet shaft is proposed for dumping at sea, refer to Section 2.3.3 Calculations of Predicted Spoil Volumes (B.4 (IV)) for full details.
For inspection purposes only. Consent of copyright owner required for any other use.
Figure 1 Location of existing and proposed discharge location in relation to the Water Framework Directive Water bodies
The tunnelled section The tunnelled section will be approximately 9 km long with an approximate finished internal diameter of 5.0 m. The tunnelled section will run between the base of the onshore tunnel inlet shaft and the base of the offshore tunnel outlet riser diffuser shaft (located 9 km offshore) in marine water depths (to seabed) of greater than 25 m below OD Malin (23 m below Lowest Astronomical Tide (LAT)). The tunnel drive will commence at the onshore tunnel inlet shaft and excavate eastwards in the bedrock under the seabed towards the offshore tunnel outlet riser diffuser shaft.
The marine site investigation results show that tunnelling in deeper bedrock offers the best conditions for tunnelling because the bedrock is mostly stable for the tunnel diameter being considered and is of low permeability. A conceptual vertical tunnel alignment based on preliminary conceptual design work is shown as a cross section in Figure 2. It should be noted that the vertical alignment indicated is purely conceptual in nature and was developed to provide only an early stage proof of concept for the tunnel. The final
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constructed tunnel vertical alignment will differ from that shown and will be based upon the detailed design proposed by the successful design and build contractor, and is expected to be no deeper than 110 m below OD Malin.
The tunnel will be constructed using a tunnel boring machine (TBM). These machines not only undertake the excavation of the ground, they also provide support to the ground (tunnel face support and all round shield support for operatives) during tunnelling. The final tunnel lining will be constructed using precast concrete ring liner elements which are assembled and installed directly by the TBM.
For inspection purposes only. Consent of copyright owner required for any other use.
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For inspection purposes only. Consent of copyright owner required for any other use.
Figure 2 Indicative cross section of the proposed tunnel
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The offshore tunnel outlet diffuser riser shaft The tunnel outlet diffuser riser shaft will be constructed at the new discharge location in Dublin Bay shown on Figure 1. A diffuser head structure will be constructed at this location to enhance dispersion of the final treated effluent discharge. The diffuser head structure will extend to approximately 5 to 7 m above the seabed level. Seabed level is approximately 25 m below OD Malin (23 m below LAT) at the site of the proposed tunnel outlet diffuser riser shaft.
It is likely that the tunnel outlet diffuser riser shaft will be constructed using an outer steel liner used for the seabed drilling operation. Once the tunnel outlet diffuser riser shaft has been drilled an inner liner would then be retrofitted within and subsequently the annulus between both liners infilled with concrete.
Construction, drilling and installation operations will likely be undertaken using a fixed position large jackup barge platform with the supporting legs positioned on the seabed for the full duration of the diffuser shaft construction works. The works construction programme estimates for the tunnel outlet diffuser riser shaft are 8 months in total carried out over two phases approximately 6 months apart.
Spoil generated during the sinking of the offshore tunnel outlet diffuser riser shaft will be removed via the drilling platforms working in conjunction with a barge disposal shuttling operation.
1.2.2 Design Build As the Ringsend WwTW Project will be awarded as a Design Build Contract, the final/detailed design will be provided by the successful contractor. The detailed design will seek to develop the conceptual design in a manner such that it has no material change on environmental impacts of the scheme. Environmental issues have been dealt with by applying the concept of “NEWT” so that the changes should be “Not Environmentally Worse Than” the concept design assessed.
For inspection purposes only. Consent of copyright owner required for any other use.
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Section 2 Loading Operations (Section B)
2.1 Alternative Measures (B.1) 2.1.1 Summary of Alternative Disposal Options Investigated This section provides details of all investigations into alternative means of disposal or reuse of the material.
The EU Waste Framework Directive (2008/98/EC) was transposed into Irish legislation by the European Communities (Waste Directive) Regulations 2011 (S.I. No. 126 of 2011). The Directive aims to promote waste prevention, to increase recycling, and to ensure better use of resources, while protecting human health and the environment. The Regulations provide the obligation to ensure that waste is managed in accordance with the waste hierarchy (with prevention at the top). The waste hierarchy comprises:
. Prevention;
- The primary objective of the hierarchy is to reduce the quantity of waste being produced. . Re-use;
- Further processing that is considered normal industrial practice is permitted (preparation for re- use). Checking (e.g., functionality), cleaning or repairing, recovery operations, by which products or components of products that have become waste are prepared so that they can be re-used without any other pre-processing. The assessment of suitability and selection of an end use can be regarded as preparation for re-use.
. Recycling;
- Any recovery operation by which waste materials are reprocessed into products, materials or substances whether for the original or other purposes. This includes the reprocessing of organic For inspection purposes only. material (composting). Consent of copyright owner required for any other use.
. Recovery;
- Examples include energy recovery, reprocessing into materials that are to be used as (secondary) fuels and backfilling operations.
. Disposal;
- This is the least favoured option and applies to landfilling (or sea disposal) operations. Any spoil that is contaminated will have to be disposed of in a suitably licensed facility. Note the OSPAR Convention bans the dumping at sea of waste, except dredged material and inert material of natural origin.
In June 2011 a study into the alternatives for disposal was undertaken by the project team and is attached in Appendix B. It examined the waste hierarchy and the viability of different recycling, re-use and disposal routes. Table 1 summarises the findings from the Tunnel Spoil Disposal Study (Appendix B) and further subsequent investigations carried out in 2012 into the alternatives for the spoil, in accordance with the waste hierarchy.
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Table 1 Summary of alternative reuse, recovery and disposal options Options Waste Summary of Option Conclusions hierarchy position Infill material Reuse The downturn in activity within the construction industry will No for have a limiting effect on the number of potential outlets for appropriate Engineering the spoil generated. The demand for infill material for projects Projects engineering projects was limited in the past and is now almost within the non-existent. Discussions with operators indicate that at required present there is little or no demand for this type of material for timescale major engineering projects. Using the material for habitat creation and coastal protection was also investigated and findings are detailed below. Roads National Roads Authority (NRA) project personnel were consulted regarding any future major road projects in the Leinster area that could utilise spoil material as road sub-base. No projects were identified and it was pointed out that projects were designed on a cut and fill basis and in order to minimise the need for imported materials. Habitat Creation In the UK excavated material from tunnel construction has been used to create new wetlands for the Royal Society for the Protection of Birds (RSPB). The RSPB were contacted to see if they would have use for the Ringsend tunnel excavated material in their current or future projects. The material is however unsuitable for their needs as it will consist of mostly gravels and they are interested in material that is predominately clays and silts for the creation of wetlands.
Coastal Protection For inspection purposes only. Consent of copyright owner required for any other use. The Office of Public Works (OPW) project personnel were consulted regarding any future coastal protection projects. They often utilise large volumes of material for beach nourishment projects. The volumes that will be produced by this project would be enough for roughly two large schemes. There is a concern though that the angular, excavated rock from the tunnel drilling would not be suitable for beach nourishment. Recently a coastal nourishment scheme in Bray used sands, rounded stones and shingles from marine dredging operations. These materials are considered more appealing for beach amenities.
There are plans by the OPW for an offshore breakwater in Courttown, Co. Wexford which may have use for some of the excavated tunnel material. This project still is in the very preliminary stages of development and does not have funding or planning permission.
Coastal Projects outside Republic of Ireland In Northern Ireland, the Rivers Agency oversees coastal
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Options Waste Summary of Option Conclusions hierarchy position protection and flood management. They were consulted with and it was determined that they have no plans for large coastal protection projects and that they now are mainly involved in maintaining the existing coastal protection structures.
Welsh coastal protection authorities (in the Dept. of Agriculture) were also contacted to see if they had any upcoming coastal protection projects. They confirmed that they only import large boulders for this purpose. The Isle of Wight Council are now at the planning stage for future coastal protection projects but did not identify any within timescale of this project.
Reclamation/ Reuse Harbour and port development would be the favourable No Infill option as the spoil would be transported by sea and avoid appropriate traffic impacts. projects within the Dublin Port required Dublin Port had intended to infill a 52 hectare area in a land timescale reclamation project as part of its Dublin Gateway proposal. Planning permission for this project was refused on environmental grounds. The new master plan published in January 2012 sets out an area of approximately 41 hectares that will require infilling. The use of the material by Dublin Port would require all statutory approvals to be in place including an environmental impact assessment. Given that such approvals are not currently in place this option cannot be relied upon at this time.
Bremore Port For inspection purposes only. Consent of copyright owner required for any other use. A new deep water port facility is proposed in Bremore near Balbriggan. There may be a requirement for considerable volumes of inert infill material for this development. The information available suggests that the facility will not be applying for planning permission before 2015. Rosslare Port There are proposals to expand Rosslare Port. Preliminary conversations with Port Authority personnel have indicated that there is a shortage of land available and that the preferred solution is reclamation. They have confirmed their interest in the spoil from the Ringsend project as infill material. However, their project has yet to be submitted for planning permission and therefore does not fit in with the timescale of this project. Ports outside of Republic of Ireland Ports contacted in Northern Ireland included, Larne Point, Warrenpoint and Belfast Port. None of these ports have large extension projects planned for the coming future. Warrenpoint
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Options Waste Summary of Option Conclusions hierarchy position Port had just completed a large extension to its harbour.
Associated British Ports the largest operator of ports in the UK were contacted. They indicated that they are at the conceptual stage of project(s) that may have a use for the material in the future. These projects could not be confirmed by Associated British Ports and do not fit within the timescale of this project.
Recycle to Recycle There is the potential for the rock spoil to be recycled into Not Produce aggregate. The aggregate could be used as a component of suitable Aggregate the concrete. Due to space limitations at the proposed tunnel material construction compound at the ESB site it would not be feasible to establish crushing, separation and storage facilities there and therefore if the spoil was to be recovered as an aggregate, the spoil would be transported to a licensed construction and demolition waste facility/ soil recovery facility where recycling can be undertaken. The potential suitability for recycling of the spoil as aggregate would be the decision and risk of the licensed facility operator. From discussions with Roadstone it is considered that recycling for reuse as an aggregate is highly unlikely due to the quality of material and based on experience form the Dublin Port Tunnel and the high dust content of the spoil. Also, there are small quantities of pyrites naturally occurring in the excavated limestone spoil which make it less suitable for construction materials.
Quarry Recovery Waste facilities that are licensed for soil recovery (quarry Viable Restoration restoration) which are large inert waste facilities accepting option (Waste natural soils and sub-soils for deposition on land. At these Licence facilities inert material such as rock spoil is used for backfilling For inspection purposes only. Facilities) and restoringConsent of existing copyright ownerquarries. required These for any facilities other use. are licensed by the EPA and the suitability of existing facilities are discussed in the attached Tunnel Spoil Disposal Study (Appendix B).
Sea Disposal Disposal An existing spoil disposal ground at Burford Bank is located Viable approximately 10 km from the Poolbeg Peninsula site and is option currently used for the disposal of dredged material from Dublin Port and for capital works from Howth Harbour under Dumping at Sea permits granted by the EPA.
Under the OSPAR Convention 1998 inert materials of natural origin are permitted to be dumped at sea.
2.1.2 Discussion of Land Recovery (Quarry Restoration) Verses Sea Disposal Options The information contained in Table 1 indicates that the two viable options for the spoil are quarry restoration and sea disposal. Quarry restoration would be considered a recovery activity under the waste hierarchy as it is a backfilling operation and as such it is considered more favourable than disposal at sea, as disposal should be the last resort.
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Disposal to sea was first considered for operational reasons as the construction site is at the tip of the Poolbeg Peninsula, on ESB lands, abutting Dublin Bay. There is an existing marine jetty adjacent to the construction site – for spoil loading operations, which is located conveniently for disposal at the existing spoil disposal area at Burford Bank. However, there are also economic and environmental including traffic benefits to the disposal at sea option. The total costs for each option are compared in the Tunnel Spoil Disposal Study in Appendix B.
A comparison of the two options in terms of 1) potential traffic impacts and 2) the economic and environmental analysis are described below.
Traffic Despite quarry restoration being higher on the waste hierarchy there are some disadvantages to this option in terms of traffic impacts. The driving distances from the site to the quarries (existing Waste licence facilities) are significant and will generate traffic volumes on the national road network.
It is proposed that heavy goods vehicles (HGVs) will remove spoil from the site continuously seven days a week, with the exception of the weekday peak network periods (7am to 10am and 4pm to 7pm Monday to Friday inclusive) when HGVs will not be permitted to run.
In Chapter 12 of the EIS the traffic impact from the construction phase was assessed. It was estimated that the spoil removal would generate a total of 135 HGV trips a day (one way “removal”), equating to 16 trips per hour and a total of about 70,000 trips over the duration of the entire project. The EIS concluded that the traffic generated by the works will have a negligible impact on the East Wall Quay/North Wall Road and Pigeon House Road/Sean Moore Road junctions. Works generated traffic represents a significant proportion (16.4 %) of the existing traffic flow through the Whitebank Road/South Bank Road junction, however, it should be noted that this junction is lightly trafficked and, as a cul-de-sac, does not form part of a critical strategic route.
By utilising an alternative disposal route that greatly reduces the number of trucks on the road network, this would have a great social benefit to local residents.
Basic environmental cost benefit analysis of disposal at sea versus quarry recovery options For inspection purposes only. Consent of copyright owner required for any other use. A basic environmental cost benefit analysis of the two options was carried out with the intention of providing indications of the relative impacts of the two alternative freight modes (i.e. truck and barge). To examine the transport modes in terms of energy efficiency, the calculations were based on the amount of fuel to transport a standard mass a standard distance, per tonne-kilometre (tonne-km). This in turn enabled the estimation of amount of greenhouse gas produced per tonne-km. Energy use per tonne-km also depends on the characteristics of the goods transported. A tonne-km is the distance travelled multiplied by the weight of freight carried. Other consequences of goods transportation such as noise, congestion, accidents and land use were not analysed in this instance.
The UK Department of Environment Food and Rural Affairs (DEFRA) produced guidelines for Greenhouse Gas Conversion Factors for Company Reporting which include emission conversion factors for tonne-km’s of freight for both HGVs and shipping (DEFRA, 2012).
The two scenarios examined were:
. Transportation by a rigid tipper truck to a quarry for restoration, located approximately 40 km from the site.
- Rigid >17t truck was taken to be representative from DEFRA, 2012; and
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. Transportation by a split bottom barge to the Burford Bank spoil disposal site in Dublin Bay, located approximately 10 km from the site.
- Small bulk carrier was taken to be representative from DEFRA, 2012; and
- The fuel consumption and emissions were also calculated for transporting the spoil from the construction compound site to the jetty for loading which is located less than 1 km away. The calculations were based on the above truck scenario.
A summary of the results of the analysis are presented in Table 2. Appendix C contains the detailed calculations and all the assumptions used. Fuel consumption was calculated based on distance travelled, the mode of transport and known fuel consumption rates.
Carbon dioxide (CO2) emissions were calculated by multiplying the weight transported/transport mode by the average transport distance/transport mode and by the average CO2-emission factor per tonne-km for the transport mode. The average CO2-emission factor per tonne-km for the transport mode was also taken from DEFRA 2012. The DEFRA conversion factors work on the basis that a lorry will run empty for part of the time in the overall transporting of the freight. This means that the freight haul distance is not required to be doubled in the calculation CO2 emissions.
The analysis showed that the estimated fuel consumption and direct fuel costs, on a per trip basis, are greater for the barge option than for the truck option. Importantly, it should be noted that a single barge carries approximately 95 times more spoil by weight compared to a truck. The total estimated fuel consumption for all trips of the barge was estimated to be 15 % of the fuel consumption for all the truck trips.
The estimated total CO2 emissions per tonne-km for all of the truck or barge trips i.e. for the duration of the project (approx 3 years), as displayed in Table 2, indicates that the CO2 emissions for the barge option was significantly less and only equated to 5% of the estimated CO2 emissions for the truck option.
Table 2 Fuel consumption and estimated CO2 emissions Summary Truck* Barge*
Estimated fuel consumption litre per tonne-km 0.03 0.04 For inspection purposes only. Per trip Estimated fuel cost perConsent tonne of copyright-km owner required for any other use.€0.04 €0.06
Estimated kg CO2 per tonne-km 150 440 For all trips Estimated fuel consumption litre 1,614,000 250,000 (i.e. duration Estimated total fuel cost €2,420,000 €376,000 of the project) Estimated kg CO2 10,663,000 503,000 *Estimated figures are rounded
The total costs of the disposal at sea route versus the recovery to landfill option are discussed in Appendix B Tunnel Spoil Disposal Study (2011).
2.1.3 Steps to be Taken to Render the Material Less Harmful Slurry separation If the design build contractor uses a slurry TBM, then a slurry separation plant is necessary to separate the slurry from the rock. The slurry is usually a mixture of water and bentonite, a smectite clay mineral. Some additives improving certain properties of the slurry can also be applied, if the geological conditions warrant this. The main purpose of the slurry is to seal the tunnel face in high permeable ground conditions (“filter cake”), support the ground, transport of the cuttings and for cooling of the cutting tools.
Should a slurry separation plant be used, the separation process uses mechanical separation processes such as screening or drying. Slurry can be re-used repeatedly provided its properties are carefully monitored and
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kept under control. Slurries are largely retained in slurry machines within a closed system (until the end of a project) and it is usually economic to recover as much as possible from the spoil before disposal.
The slurry will not be dumped at sea. No further processing of the slurry is required other than normal practice, it is an integral part of the process and so the slurry is a non-waste by-product. The process does not separate waste streams but rather extracts slurry from the rock spoil for beneficial reuse. The slurry only becomes a waste at the end of the project. Usually, the cheapest acceptable method of disposal of slurry is to place it in an approved landfill, with transportation by a licensed carrier. The material will be tested in a laboratory to find out whether it is suitable for landfill and whether the site in question is allowed to accept the waste.
The method for drilling of the diffuser shaft is currently unknown and will be determined by the design build contractor. If slurry is used for drilling the diffuser shaft the slurry will be separated from the marine sediment and rock, either onshore or on the jack-up platform, to the same standard as for the tunnelled rock operation. 2.2 Purpose of the Operation (B.2) Ringsend WwTW Extension Project involves the construction of a long sea outfall tunnel (LSOT) for treated effluent. As a result of the tunnelling for the LSOT a large volume of excavated material will be generated (i.e. capital works).
The bulk of the spoil will be a clean natural inert material. The excavated material generated is defined as a waste as there is no potential for use of the excavated material on site, therefore to be classified as a waste material in accordance with the waste management regulations. If a use is found for the material then it does not have to be defined as a waste. A full discussion of the material being defined as a waste is provided in the Tunnel Spoil Disposal Study in Appendix B. The bulk of the spoil generated on the project will be inert material as described in Section 3.1.3.
The bulk of the spoil will be required to be transported from the construction compound site located on the Poolbeg Peninsula for disposal. A small quantity of the spoil from marine excavation of the diffuser shaft must also be disposed of.
For inspection purposes only. Discussion on the overall need for theConsent upgrade of copyright to the owner Ringsend required for WwTW any other use.is contained in Section 1.2 and a discussion of disposal alternatives is discussed in Section 2.1. 2.3 Details of the Loading Operation (B.3 and B.4) 2.3.1 Date of Commencement of Loading Operations (B.4 (I)) The loading operations are due to commence when the bedrock will be excavated from the inlet shaft which is scheduled to be at the beginning of 2014.
2.3.2 Location and Method of Loading (B.4 (II)) The Ringsend Poolbeg ESB site is proposed to be the launch site for the TBM and all associated construction works operations (with the exception of the offshore tunnel outlet marine diffuser riser shaft), as such it is the site where the tunnel inlet shaft will also be excavated and constructed and where the TBM tunnelling limestone spoil will be removed from the tunnel. Ringsend Poolbeg ESB site currently operates under an IPPC licence number P0577-02. ESB have agreed in principle to seek an amendment to their licence from the EPA to temporarily change the site boundary of the IPPC licence during construction of the proposed Ringsend WwTW LSOT.
Excavated materials from tunnelling and the excavation of the bedrock from the inlet shaft will be stock- piled temporarily above ground in the tunnel construction compound in an area reserved for this purpose.
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The area available for stockpiling the material will be sufficient to hold a minimum of two days’ worth of spoil output. The storage of the spoil on site is classified as temporary storage under the Waste Management Acts 1996 to 2011 (Acts), as it will be held onsite for less than 6 months.
The spoil will be transported by truck from the tunnel construction compound to the proposed loading area, the Pigeon House Jetty at Ringsend. The jetty is owned by Dublin City Council and it is located less than a kilometre by road from the onshore tunnel site compound. The jetty was previously used to load sludge from the Rinsgend WwTW onto barges.
The spoil is proposed to be loaded onto a conveyer and subsequently loaded onto a barge at the end of the jetty. The proposed spoil disposal area is located about 9.5 km from the Pigeon House Jetty at Ringsend. The loading operation is shown in Appendix Figure A.1 Loading Area (Ref B.3).
Note that there may be a separate loading area located at the diffuser shaft location. 0.8 % of the total spoil generated will be at the diffuser site and the spoil may be loaded onto a barge for disposal at sea at this location. Alternatively it may be brought back to land for separation depending on the drilling methodology chosen by the design-build contractor. The location of this loading area is shown in Appendix Figure A.2 Diffuser Shaft Loading Area (Ref B.3).
The locations of the areas where the spoil will be loaded from are given here are in Irish Transverse Mercator (ITM) Co-ordinates and WGS84 respectively, as follows:
. The onshore tunnel inlet shaft (centre point): E 720982 N 733526 (Lat 53° 20’ 17’’ Long -6° 11’ 0’’)
. The tunnelled section (West to East): E 720982 N 733526 (Lat 53° 20’ 17’’ Long -6° 11’ 0’’) to E 729690 N 732763 (Lat 53° 19’ 45’’ Long -6° 3’ 11’’)
. Tunnel outlet diffuser (centre point): E 729690 N 732763 (Lat 53° 19’ 45’’ Long -6° 3’ 11’’). 2.3.3 Calculations of Predicted Spoil Volumes (B.4 (IV)) An estimate of the spoil quantities that will be generated by various construction operations are provided in the EIS. The spoil proposed to be dumped at sea is summarised in Table 3. It is expected that the tunnel will be constructed entirely in bedrock apart from the inlet and marine diffuser shafts. The estimates are an For inspection purposes only. approximation of the volumes and as Consentsuch are of copyright rounded owner to required the nearest for any other 1,000 use. cubic metres of in situ volume and are listed in Table 3. The total estimated spoil proposed to be disposed of at the spoil disposal area at Burford Bank is 824,000 tonnes.
Table 3 Estimate of spoil quantities from tunnelling works proposed for dumping at sea
Type A - Assumed Assumed Type B - In Situ Bulked Solid length / external 1 Sediments Volume Volume Bedrock 3 depth diameter 2 Weight Weight Cubic Cubic m m Tonnes Tonnes metres metres Inlet Shaft – Bedrock 70 22.5 28,000 47,600 70,000 - Tunnel – Bedrock 9,000 6.5 299,000 508,300 747,500 - Diffuser Shaft – Bedrock 60 6.5 2,000 3,400 5,000 - Diffuser Shaft – Bay 25 6.5 1,000 1,000 - 1,500 Sediments Total Quantities – Cubic metres 330,000 560,300 - - Total Weight – Tonnes - - 822,500 1,500 Notes: 1. The volume of material that is removed to create the tunnel (in situ volume) and then a bulking factor of 1.7 is applied to bedrock in order to estimate the spoil volume for transportation purposes.
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2. The mass of the excavated bedrock is calculated on the basis of the limestone having a mass density of 2.5 tonnes/cubic metre. 3. The mass of the excavated sand and gravel is assumed to have a bulk density of density of 1.5 tonnes/cubic metre.
The two main types of spoil generated will be bedrock and overburden as described below.
Bedrock: The tunnel will be drilled through predominantly limestone rock. Drilling through rock yields large volumes of spoil in the form of drill cuttings (rock spoil). It is estimated that the rock spoil from the excavations will be in the order of 822,500 tonnes. This represents 99.8% by weight of the total material to be removed from the construction of the tunnel that is proposed to be dumped at sea.
Overburden: The proposed tunnel will have an onshore inlet and a marine diffuser shaft, both of which will extend through overburden material. Overburden includes marine sediments, weathered bedrock material, and glacial tills/clays, located above the underlying bedrock. The total volume of overburden material resulting from the diffuser shaft excavations will be approximately 1,500 tonnes. It is not proposed that the overburden material from the inlet shaft will be disposed of at sea and as such the volumes are not included below.
Total quantities to be loaded (B.4 (IV)) The rate of spoil generation for removal from the tunnel excavation will be dependent on the rate of progress of the TBM. It is estimated that the TBM will progress at an average rate of 16.5 linear metres per day which is the long average tunnel rate and a maximum progression rate of 30 linear metres per day. The total quantities of spoil to be generated per day based on the long average progression rate, is 930 m3 and the maximum quantity of spoil generated per day would be 1,690 m3.
Note that the excavation of the inlet shaft is not concurrent with the tunnel and diffuser excavations. The inlet shaft will be constructed first and this is estimated to take 12 months. It will be completed prior to commencement of tunnelling operations. The TBM will then be launched from the inlet shaft and the tunnel drive is expected to take up to 24 months, with the offshore diffuser shaft being constructed in parallel.
The estimated load is 930 m3 which is based on the total quantities of spoil to be generated per day (based on the long average progression rate for the tunnelling) and the typical barge vessel having a capacity of 1,000 m3. Table 4 shows the total quantities of spoil to be generated per day, week and month based on the 3 For inspection purposes only. load of 930 m . Consent of copyright owner required for any other use.
Prior to loading the spoil will be stock-piled temporarily on the onshore construction compound in an area reserved for this purpose (tunnel arisings storage area) and this area will be sufficient to hold a minimum of two days’ worth of spoil output.
Table 4 Total quantities and rates to be loaded Tunnel & Diffuser Shaft Spoil Inlet Shaft Spoil Bulked Bulked Weight Weight Volume Volume (Tonnes) (Tonnes) (Cubic metres) (Cubic metres) Total Spoil Volumes for the ~Project Bedrock 511,700 751,000 47,600 70,000 Bay Sediment 1,000 1,500 - - Total Bedrock plus Bay Sediment 512,700 752,500 47,600 70,000 Rates to be Loaded Spoil Removed/ day (i.e. per load) 930 1,400 200 300 Spoil Removed/ week 6,500 9,800 1,400 2,100 Spoil Removed/ month 29,300 43,400 6,200 9,300
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Section 3 Material Analysis (Section C)
3.1 Characteristics and Composition of the Substance or Material for Disposal (C.2) This section gives the particulars of the nature and composition of the substance or material to be disposed of at sea.
3.1.1 Background to Marine Site Investigations To aid with the design of the long sea outfall tunnel, it was necessary to undertake a large scale marine site investigation in Dublin Bay. The site investigations commenced in September 2010, which involved the sinking of 23 boreholes; at the Poolbeg Peninsula and in Dublin Bay, as far East as Burford Bank. Additionally, a geophysics testing programme was carried out throughout large parts of the Bay.
Figure 3 shows the locations of the boreholes that were drilled during the site investigations in Dublin Bay. Results of the site investigations are discussed in the following sections.
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Figure 3 Marine site investigation borehole locations
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The Calp limestone is identified as underlying the majority of Dublin and it was found in the majority of boreholes along the proposed tunnel route, during the marine site investigations. It consists in particular of layers of limestone as well as of layers of mudstone. The limestone is a medium strong dark grey coloured argillaceous limestone. Crinoid stems and shell fragments are frequently found in the bedrock, usually measuring < 4mm diameter. It displays calcite veining in many locations and this veining is sometimes described as closely spaced subvertical veining. These veins can range in size between < 0.5mm to < 5mm. Pyrite crystals were also present in small amounts in the limestone, and are described as rare to frequent in some cores. The pyrite crystals were usually < 2mm in size.
Limestone formations of the Tournesian series of the Lower Carboniferous were found at boreholes BH M 21 and BH M 11 (proposed diffuser location). The rock is in general slightly more weathered, fractured and fissured than the Calp limestone elsewhere.
3.1.2 Material Form and Physical Properties Excavated rock cuttings will be crushed within the TBM. The final particle size of the material is determined by the type and design of the TBM as well as by the rock conditions and characteristics. The TBM is designed to suit the lining of the tunnel and so design responsibility rests with the contractor under a Design Build Contract. There are two main types of TBM that may be used; a slurry TBM or an earth mud (Earth pressure balanced shield, EPBS).
The maximum size of the rock cuttings will not exceed about 10 cm in diameter and approximately 4 cm in thickness. It is estimated that the average composition of the material will be that shown in Table 5, with the highest portion being gravel.
Table 5 Material composition (based on BS 1377-2:1990)
Estimated Average Material Category % Small cobbles (< 10cm) 19 Gravel (> 2mm) 51 Sand (0.06 – 2 mm) 13 Silt (0.002 – 0.06 mm) 6
Clay (< 0.002 mm) 11 For inspection purposes only. Consent of copyright owner required for any other use.
The Calp limestone consists mostly of limestone rock but as well as some mudstone rock sections. The limestone rock sections are in general very stable and competent. In cases of presence of clayey fillings or fractured zones, the stability is reduced. The physical properties of limestone can be summarised as follows:
. Limestone is quite soluble in water which leads to erosion over geological time.
. Generally the specific gravities of crystalline forms of calcium carbonate and dolomite at 20°C: calcite 2.72 g/cm3, aragonite 2.94 g/cm3 and dolomite 2.86 g/cm3 (Oates, 1998).
. Test results from the Marine Site Investigation showed that the:
- Slake durability tests on limestone parts indicate that limestone is of high to very high durability. Slake durability tests on the mudstone parts indicates a medium durability
- Density was determined by immersion in water or water displacement. Bulk density of the limestone ranges from 2.2 to 2.7 Mg/m3.
- The rock is in general of a very stiff type. Elasticity moduli of more than 50,000 MPa in intact rock were encountered. In more weathered/disturbed sections an elasticity modulus of ca. 5,000 to 10,000 MPa was found.
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- The unconfined compression strengths range from ca. 20 to 170 MPa.
- A rock abrasity index (RAI) of less than 30 in general has been derived from the reported data so far (with single highest values of ca. 40). The abrasivity is therefore classified as low. Some minor sections may be classified as medium abrasive.
. The bedrock around the potential diffuser location differs from the properties described above. Unconfined compression strength and stiffness is lower.
. The bedrock around the onshore location differs from the properties described above. The bedrock is highly fractured. No sufficient samples could be cored to perform unconfined compression tests. Based on this and on visual inspection of the cores it is believed that the stiffness of the bedrock is lower than described above (less than 5,000 MPa).
The marine sediment encountered in borehole BH M 11 is taken to be representative of the type of marine sediment that will be drilled for the diffuser shaft. The surface seabed sediments encountered at borehole M11 location were described as very soft grey slightly sandy clay with rare shell fragments. The depth of overburden was 25 m below seabed level at this location, with the overburden material in the borehole consisting of 52 % clay, 36 % gravel and 12 % sand. No sediment/overburden material from the onshore tunnel inlet shaft will be dumped at sea.
3.1.3 Chemical Properties
Limestone is a naturally occurring rock that consists principally of calcium carbonate (CaCO3). Limestone
often contains variable amounts of silica (SiO2) and aluminia (Al2O3) (Oates, 1998).
The OSPAR Convention (1998) for the Protection of the Marine Environment of the North East Atlantic entered into force in 1998. Under the convention the dumping of all wastes or other matter is prohibited. All countries who have signed up must control deposits to the sea and are only permitted to dispose of the following:
. Dredged material;
. Inert materials of natural origin, that is solid, chemically unprocessed geological material the For inspection purposes only. chemical constituents of whichConsent are unlikely of copyright to owner be released required for into any other the use. marine environment; and
. Fish waste from industrial processing operations. Exemptions from detailed characterisation Under the OSPAR (1998) Guidelines for the Management of Dredged Material (Reference 1998-20) previously undisturbed geological material is exempt from detailed characterisation which includes chemical and biological, see extract below:
“5.2 Dredged material may be exempted from the testing referred to in paragraphs 5.4 to 5.9 of these Guidelines if any of the criteria below are met:
(a) it is composed of previously undisturbed geological material; or
(b) it is composed almost exclusively of sand, gravel or rock; or
(c) in the absence of appreciable pollution sources, which should be supported by existing local information so as to provide reasonable assurance that the dredged material has not been contaminated, the quantity of dredged material from single dredging operations does not exceed 10,000 tonnes per year.
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Dredged material that does not meet one of these requirements will need further stepwise characterisation to assess its potential impact (i.e. see paragraphs 5.3-5.9).”
The Marine Institute and the EPA (email 3/05/2012 – CDM Smith reference 75461/CI974) and the Radiological Protection Institute of Ireland (RPII) (email dated 17/08/2012 – CDM Smith reference 75461/CI1149) were consulted with, and it was confirmed that testing of the limestone material to determine its chemical and biological nature would not be necessary as the limestone is an inert material of natural origin and does not consist of constituents likely to be released into the environment.
It was also determined through discussions with the Marine Institute (email dated 17/08/2012 – CDM Smith reference 75461/CI1151) and the RPII (email dated 22/08/2012 – CDM Smith reference 75461/CI1152), that the marine sediment from the drilling of the diffuser shaft would not require materials analysis, given the relatively small quantity (ca. 1,000 m3) and given its close proximity to the spoil disposal area at Burford Bank where it is proposed to redeposit it. Also there is no reason to believe that the material contains anything other than unmodified natural radionuclides at background comparable with that in the receiving environment and therefore can be dumped at sea (Cefas, 2006).
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Section 4 Impact on the Receiving Environment (Section D)
4.1 Introduction This section describes the assessment of the impact on the receiving environment. The existing environment is explained followed by the assessment of the dilution and dispersal characteristics, the impact on flora and fauna and other marine uses and resources. 4.2 Existing Environment 4.2.1 Sea Bottom Characteristics The Burford Bank sits centrally across the mouth of Dublin Bay, approximately 10 km east of Poolbeg. Oriented north-south, the Burford Bank is a linear sand ridge about 5 km long and 1.5 km wide, and seabed rises to within 5 m of the water surface. Bathymetric comparisons suggest that the Burford Bank and smaller similar offshore banks are quasi-stable over time, probably maintaining their position due to the interaction between wave and current regimes (Wheeler et al., 2000).
West of the Burford Bank seabed ripples of typically 0.3 to 0.5 m in height with crests typically 8 m apart and orientated 110 / 290° are seen. These commence in the west from water depths of about 20 m Chart Datum (CD) and continue east towards the bank until water depths of about 5 m CD. Within the spoil disposal area there are some seabed mounds of perhaps less than 1 m in height refer to Appendix Figure A.3.
The sediment in Dublin Bay is predominantly sand and silt. The seabed characterisation of Dublin Bay has been carried out by Geological Survey of Ireland (GSI) and Marine Institute (INFOMAR) and a map showing the classification is reproduced in Figure 4. The distribution of sediment types are largely a function of the currents. The Burford Bank spoil disposal area is predominately mud to fine sand to the eastern end, this is where the currents are weaker and mud accumulates. To the western edge of the spoil disposal area there is coarse sandy gravel sediments due to stronger currents. For inspection purposes only. Consent of copyright owner required for any other use.
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Figure 4 Seabed characterisation of the spoil disposal area (reproduced from INFOMAR, 2010)
4.2.2 Dispersal Characteristics For inspection Background purposes only. Data Consent of copyright owner required for any other use. Water depths For the Ringsend WwTW Extension Project a bathymetric survey was carried out in the Dublin Bay area using a multibeam echo sounder between October and December 2010. Refer to Appendix Figure A.3 for a map of the bathymetry of the spoil disposal area.
Within the spoil disposal area the bathymetry data shows that the depth of the seabed ranges from 12.5 m to 24 m CD. The average depth was calculated to be 19 m CD.
Tidal data and currents The tides at Dublin Port are semi-diurnal; that is they exhibit two high tides and two low tides each day. The range of mean spring and neap tides (low water to high water) is 3.4 m and 1.9 m respectively (UKHO, 2012).
At low tide at Dublin Port the flood wave in the Irish Sea is strongly developed with a northerly flow which sets up a clockwise circulation in the bay with north westerly currents in the south of the bay and north easterly to the south of Howth Head. This pattern persists throughout the flooding tide with a well developed clockwise circulation.
In a study carried out by Irish Hydrodata Ltd (1995) tidal profile measurements were taken at various depths within a survey area west of Burford Bank, a summary of the current patterns are presented in Table 7.
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Table 6 Tidal level in metres relative to Chart Datum (UKHO, 2012) Tidal Level Dublin Port (metres) Highest Astronomical Tide (HAT) 4.7 Mean High Water Spring (MHWS) 4.1 Mean High Water Neap (MHWN) 3.4 Mean Sea Level (MSL) 2.4 Mean Low Water Neap (MLWN) 1.5 Mean Low Water Spring (MLWS) 0.7 Lowest Astronomical Tide (LAT) -0.1
Table 7 Summary of current data (Irish Hydrodata Ltd, 1995) Depth below Surface Spring Tide Neap Tide Flood Ebb Flood Ebb 7 m 0.8 0.75 0.52 0.4 14 m 0.68 0.65 0.45 0.35 21 m 0.6 0.55 0.4 0.3 Flow Direction 010° 190° 360° 180°
With the purpose of providing data for calibration and verification of a water quality model for the Ringsend WwTW Extension EIS, DHI conducted a current measurement study in Dublin Bay. The full Marine Survey Report is contained in Appendix D of this report. Two Acoustic Doppler Current Profilers’ (ADCP) were deployed on the seabed; one ADCP – which only measured currents – was deployed inside Burford Bank (station 1) and another (station 2) measuring waves and current was deployed outside Burford Bank. It also comprised vessel-based mapping of spatial current distribution in Dublin Bay and a temperature/ conductivity string as well as float trackings. A map displaying the survey locations is provided in Figure 5.
From the Irish Hydrodata Ltd study (1995) and the DHI study in 2010 it can be seen that in the spoil disposal area there is a northward flow on the flooding tide and a southward flow on the ebb, i.e. there is a strong N- S direction to the currents. Figure 6 gives an example of current data (current rose) from station 1, which was located inside of Burford Bank to the south For inspection of the spoil purposes disposal only. area. The rose shows the distribution of Consent of copyright owner required for any other use. current velocity on direction intervals. The prevailing current direction is north, that is, the strongest current is running in a northerly direction (for this period).
The depth averaged current velocity measured at station 1 between 11 to 26th April 2010 ranged from 0 to 0.6 m/s with an average of approximately 0.25 m/s and for station 2 the range was 0 to 0.9 m/s with an average of approximately 0.4 m/s (see time series in Appendix D).
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© Products Licence No. 012010.005
For inspection purposes only. Figure 5 Location of DHI marine surveyConsent area of copyright owner required for any other use.
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Figure 6 Example of presentation of current data (current rose) from station 1
For inspection purposes only. Wind and wave data Consent of copyright owner required for any other use. Dublin Airport synoptic station is located approximately 17 km from the spoil disposal area. Climate averages for wind data are computed over a 30 year period of consecutive records, which is considered long enough to smooth out year to year variations. 1981 to 2010 is used as the baseline period for day-to-day weather and climate comparisons. Table 8 summaries the average yearly wind speeds at Dublin Airport within this period. The Dublin Airport windrose indicates that the prevailing wind direction is from the south west.
Table 8 Wind data - Dublin Airport 1981–2010 Annual Average 1981-2010 Annual Average 1981-2010 Wind (knots) (km/hr) Mean monthly speed 10.3 19 Max. gust 80 148 Max. mean 10-minute speed 55 102 Mean number of days with gales 8.2
Met Éireann launched a marine weather buoy in the Irish Sea in 2001, which is known as M2. It is the closest Met Éireann buoy located some 43 km from the spoil disposal area (and 37 km east of Howth Head). The mean significant wave height recorded between 2001 and 2010 was 1.4 m with a maximum significant wave
height of 5.3 m (Met, 2012). Met Éireann record wave heights as significant wave height (HS) which is
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defined as the average height (trough to crest) of the highest one-third of the waves. This statistical measure was designed to correspond to the wave height estimates made by experienced observers as they do not notice all of the small waves that pass by.
Station 2 in the DHI Marine Survey (Appendix D) measured waves and current was deployed outside Burford Bank, see location in Figure 5. Wave data from station 2 were presented as time series of significant wave height (Hm0). Significant wave height (Hm0) is an energy-based statistic equal to four times the standard deviation of the sea surface elevations.
The long term wave height averages and the averages over the period the ADCP were deployed by DHI are shown in Table 9. The measurements at station 2 are taken to be more representative of the wave environment of the spoil disposal area, with higher waves expected further out into the Irish Sea at M2.
Note that while the significant wave height HS and Hm0 can be similar they are not directly comparable. In shallow water HS may be significantly larger than Hm0, especially for low-frequency waves.
Table 9 Summary of wave heights Annual Average Average Wave height 2001-2010 11th Apr to 11th May 2010 Station 2 Location M2 Irish Sea Buoy Outside Buford Bank
Unit HS in metres Hm0 in metres Mean Wave Height 1.4 0.6* Max. Wave Height 5.3 2.1* *approximate values
The wave climate in Dublin Bay is affected by both wind waves and swells. Figure 7 gives an example of presentation of wave data (wave rose) from station 2. The rose shows the distribution of wave height on direction intervals. The predominant wave direction for the period the wave measurements were taken, is north east, that is the largest waves are arriving from north east.
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Figure 7 Example of presentation of wave data (wave rose) from station 2.
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4.2.3 Water Characteristics DCC contracted CDM Smith to carry out a sampling programme from December 2008 to November 2009 to collect water quality data in Dublin Bay. The sampling location referred to as “5 km ESE Poolbeg Lighthouse” is located just 2 km west of the spoil disposal area, and is the most easterly sampling location within the bay, (see Figure 8). Water quality results for 23 samples are summarised in Table 10.
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Figure 8 Water Quality Montiroing Loactions within Dublin Bay
Table 10 Average (or Median) water quality results at “5 km ESE Poolbeg Lighthouse” from 2008-2009 Environmental Quality Objectives Parameter Unit Surface Depth for Coastal Waters (S.I. No. 272 of 2009) Salinity PSU* - 33.3 33.2 Temp. °C - 10.8 10.8 BOD mg/l ≤4.0 (95 %ile) <2 <2 Between 80 % to DO % sat 101.7 100.4 120 % sat. (95 %ile) Ammonia mg/l N - 0.016 0.018 Good status ≤0.25 Dissolved Inorganic Nitrogen (DIN)** mg/l N 0.04 0.053 High status ≤0.17 Molybdate Reactive Phosphorus (MRP)** mg/l P - 0.013 0.016 Chlorophyll a mg/m3 - 0.9 1
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* The practical salinity unit (psu) defines salinity in terms of a conductivity ratio of a sample to that of a solution of 32.43456g of KCl at 15°C in 1 kg solution. A sample of seawater at 15°C with conductivity equal to this KCl solution has a salinity of exactly 35 psu. ** Median values
The waters in Dublin Bay itself are well mixed throughout the year because of strong tidal mixing and a shallow water column. There is an insignificant annual variation in salinity ranging from 32 to 35 PSU with an average of 33 PSU at “5 km ESE Poolbeg Lighthouse”.
The European Communities Environmental Objectives (Surface Waters) Regulations 2009 (S.I. No. 272 of 2009) apply to all surface waters and are made to give effect to the measures needed to achieve the environmental objectives established for bodies of surface water by the Water Framework Directive. The water quality standards proposed for the general physico-chemical conditions supporting the biological elements coastal waters are listed in Table 10. Results for “5 km ESE Poolbeg Lighthouse” are summarised and highlighted as follows:
. Dissolved Inorganic Nitrogen (DIN) is considered to be the limiting nutrient in coastal waters and a breach of the environmental quality standard may lead to eutrophic conditions (algal blooms, etc). At the 5 km ESE Poolbeg Lighthouse sampling location within Dublin Bay the median value of DIN was found to be below the value of 0.17 mg/l N for high status (34.5 psu);
. Ammonia and Molybdate Reactive Phosphorus (MRP) results were also shown to be within normal ranges for coastal waters;
. Biological Oxygen Demand (BOD) concentrations were generally low, with 90 % of the reported
measurements below the limit of detection of 2.0 mg/l O2, for the method used; and
. Results for Dissolved Oxygen (DO) all fall well within an acceptable range, as defined by lower and upper limits required for DO saturation in coastal water bodies.
Trophic status The status of coastal water bodies is assessed by the EPA using the Trophic Status Assessment Scheme (TSAS) as set out in Water Quality in Ireland 2007-2009 (EPA, 2010). The scheme compares the compliance For inspection purposes only. of individual parameters against a set Consentof criteria of copyright indicative owner required of trophic for any state.other use. These criteria fall into three categories nutrient enrichment, accelerated plant growth and disturbance to the level of dissolved oxygen normally present.
Based on criteria levels of nutrient enrichment (DIN and MRP), chlorophyll levels and percentage saturation of DO, the trophic status of the water can be classified into eutrophic, potentially eutrophic, intermediate and unpolluted based on the following:
. Eutrophic water bodies are those in which criteria in each of the categories are breached;
. Potentially Eutrophic water bodies are those in which criteria in two of the categories are breached and the third falls within 15 per cent of the relevant threshold value;
. Intermediate status water bodies are those which breach one or two of the criteria; and
. Unpolluted water bodies are those which do not breach any of the criteria in any category.
The outcome of the most recent TSAS of estuarine and coastal waters for the period 2007-2009 showed that Dublin Bay was unpolluted as displayed in Table 11.
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Table 11 Dublin Bay TSAS Score (EPA, 2010) TSAS Criteria Threshold Value Result Winter DIN Median (mg/l) 0.442 0.171 Pass Winter MRP Median (µg/l) 43 26 Pass Summer DIN Median (mg/l) 0.378 0.057 Pass Summer MRP Median (µg/l) 42 14 Pass Chloro. Median (µg/l) 10.6 2.7 Pass Chloro 90 percentile (µg/l) 21.1 3.6 Pass Opportunistic Algae (WFD Classification 0.6 No value - Score) DO % sat 5 percentile 79 96.0 Pass DO % sat 95 percentile 121 111.0 Pass BOD Median (mg/l) 4 <2 Pass Unpolluted
4.2.4 Flora and Fauna Natura Environmental Consultants were commissioned to undertake a Screening for Appropriate Assessment for the proposed loading and spoil disposal (full report contained in Appendix F). This section briefly summarises the existing environment of flora and fauna, refer to Appendix F for a full description of the existing environment.
Marine Benthic Communities A baseline marine benthic ecological assessment of the Burford Bank spoil ground was carried out in 2008 on behalf of Dublin Port Company. Eight stations located within the spoil ground and two control sites (located southwest of the spoil ground) were surveyed in November 2007. Five replicate van Veen grabs were collected at each station for faunal analysis and a sixth was collected for sediment grain size and organic carbon analysis. Five replicate Sediment Profile Images were also collected at each station.
The survey results revealed that the spoil ground consisted of mud and muddy fine sands with a low organic content. The spoil ground was characterised by two faunal communities, consisting of 1) the polychaetes For inspection purposes only. Nephtys hombergii, Ophelia borealisConsent and Spiophanesof copyright owner bombyx required forand any 2) other the use. bivalve Thracia phaseolina, the brittle star Amphiura filformis and the polychaete Lagis koreni. The macrobenthic communities are typical of these habitat types. (Kennedy, 2008).
There was however a generally low similarity between replicates from the same station, indicating that the sediment type is patchy on small scales or subject to frequent perturbation. The stations that did show some degree of overlap were the stations located closest together, indicating that the community distribution reflected spatial variability, most likely in sediment type. This spatial variability is probably indicative of physical stress due to shallow water depths, currents, tides and passing heavy shipping (Kennedy, 2008).
AQUAFACT carried out a benthic survey in the area of the proposed outfall location for the Ringsend WwTW Extension EIS. Three of the survey locations were located in the southwestern part of the spoil ground, while the remainder, were located to the west of the spoil ground. This survey revealed that the substrata in this area consisted of sandy sediments with varying proportions of gravel and mud. Organic carbon levels in the area were considered to be high. The fauna observed in the area was similar to that found during a 1971/72 survey of the same area carried out by Walker & Rees (1980). This stability over a period of ca 40 years indicates that the benthic habitat of Dublin Bay has not altered in that time period and that the biological communities are also stable.
All species recorded are common in Irish waters and typical of the sedimentary habitats encountered. None of the species recorded are endangered, rare or of conservation importance.
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Natura 2000 Sites
Flora and fauna in Ireland are protected at certain sites for their nature conservation importance and to legally protect faunal and floral species and important/vulnerable habitats. The two main categories of designation are as follows:
. Candidate Special Areas of Conservation (cSAC) are designated under the EU Habitats Directive (92/43/EEC) which are transposed into Irish law by the European Communities (Birds and Natural Habitats) Regulations, 2011 (S.I. No 477 of 2011); and
. Special Protection Areas (SPAs) are designated under the EU Birds Directive (79/409/EEC) which are transposed into Irish law by the European Communities (Birds and Natural Habitats) Regulations, 2011 (S.I. No 477 of 2011). These cSACs and SPAs are considered to be of international importance.
Table 12 lists the environmental protected areas in the vicinity of the spoil disposal area. A more detailed account of these protected areas can be found in Appendix F.
Table 12 Natura 2000 Sites Distance from Natura 2000 Site Site Name Site Code Spoil Ground Howth Head IE000202 2.8km N Special Area of Conservation North Dublin Bay IE000206 4.9km NW (SAC) South Dublin Bay IE000210 7.2km W Howth Head Coast IE004113 2.6km N North Bull Island IE004006 3.4km NW Special Protection Area (SPA) South Dublin Bay & River Tolka IE004024 5.7km W Dalkey Islands IE004172 5.2km SW Potential SAC/SPA Kish Bank n/a 4.9km* SE
Fish Stocks, Spawning and Nursery Areas Recreational fishing from the shore occurs all around Dublin Bay. A wide variety of species are fished e.g. For inspection purposes only. mackerel, garfish, coalfish, plaice, dab,Consent dogfish, of copyright ray, wrasse, owner required whiting, for any bass, other use. mullet, pollack, codling, conger,
flounder, rockling, pouting, spurdog and tope.
There are commercial fisheries for Nephrops, cod (Gadus morhua), plaice (Pleuronectes platessa) and sole (Solea solea) in the Irish Sea (Marine Institute, 2011). The most abundant species in trawl surveys are dab (Limanda limanda), plaice (Pleuronectes platessa), solenette (Buglossidium luteum) and common dragonet (Callionymus lyra) along with large numbers of poor-cod, whiting and sole (Marine Institute, 2011). Lesser spotted dogfish Scyliorhinus canicula is abundant throughout (Marine Institute, 2011). The following shellfish species are fished in the Dublin Bay area: lobster, razor clams, scallops, velvet crabs and whelk. It should be noted that Dublin Bay is not a designated shellfish waters under the Irish Shellfish Regulations (SI 200/1994).
The area in and around the spoil ground is a spawning and nursery ground for cod, a nursery ground for haddock, a nursery area for horse mackerel and mackerel and a spawning ground for whiting (Lordan & Gerritsen, 2009).
While not commercially targeted, sandeels are common to all Irish sandbanks and are found at the Kish Bank.
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Seabirds Seabird distribution has been surveyed in several broad surveys in the Irish Sea since the mid-1980s. One survey by Newton and Crowe (1999) reported on a series of more targeted surveys of seabirds at the north end of the Kish Bank carried out in August and September 1999. The core of the survey covered an area centred on the Kish Lighthouse. It should be noted that this survey did not cover the Burford Bank.
A total of 3,015 birds of 26 species were recorded around the north end of the Kish Bank in August and September 1999. Of these 25 were true seabird species and one (Dunlin) was a wader species. Common Guillemots, Black-legged Kittiwakes and Common Terns were the most commonly recorded species while Roseate Terns, Kittiwakes and Common Terns were the predominant species seen roosting on the Kish Lighthouse. Over 1,000 terns were estimated to be roosting here on 3rd September 1999. A high number of Common Guillemots (1,482 on 3rd September) was also recorded in the area (Newton and Crowe 1999).
A range of distributional patterns was observed in the seabird surveys of the Kish Bank. Great Cormorants and Shags were mainly found directly over the shallow water of the bank whereas large gulls (Larus species) appeared to be randomly scattered and occurred at approximately equal densities in the vicinity of the bank and on transects between Howth Head and the Kish Lighthouse. Black-legged Kittiwakes were present both over and to the east of the Bank with reasonable numbers also towards the seabird colony on Howth Head. Terns were mostly recorded on or to the east of the northern half of the Bank and auks, principally Common Guillemots, were concentrated to the east of the Bank. The highest densities recorded for all seabirds combined (in birds per square kilometre) were 51-100 birds/km2. Significant densities of auks (mainly Common Guillemots) occurred at up to 51-100 birds/km2 along several of the transects (Newton and Crowe 1999).
Marine mammals The Irish Whale and Dolphin Group records sightings of cetaceans and these are available on-line (at www.iwdg.ie). The nearest locations to the proposed spoil disposal area are at Kish Lighthouse, Howth Head and Dalkey. A summary of recent sightings at each of these locations is given in Appendix F. Harbour porpoises are frequently recorded at all sites (up to 24 sightings in one year in 2011 at Howth Head). Minke Whales are also regularly recorded at Kish Lighthouse and occasionally at the other locations. Bottlenose Dolphin are being recorded with increasing frequency, especially at Dalkey.
For inspection purposes only. A targeted survey of Harbour PorpoiseConsent in theof copyright Dublin owner Bay required area, for in any July other-September use. 2008, found high densities of these cetaceans in the area (including in the vicinity of the Burford Bank) (Berrow et al. 2008). Density estimates ranged from 0.48 to 2.05 per km2 which gave abundance estimates of between 56 and 238 porpoises for the whole sample area. The mean group size was quite consistent ranging from 1.08 to 1.50. The overall density estimate was 1.19 per km2 which gave an estimated abundance of 138±33 porpoises. This represents one of the highest densities of the species recorded in Ireland to date (Berrow et al. 2008).
Both Grey Seals (Halichoerus gryphus) and Harbour Seals (Phoca vitulina) are present in Dublin Bay with a regular haul-out at the eastern end of the North Bull Island. Lambay Island and Ireland’s Eye hold a significant breeding colony of Grey Seals with an estimated all-age population of 203 to 261 animals. There is also a haul-out of Harbour Seals on Lambay (O Cadhla et al. 2007). Grey Seals, in particular, range widely outside the breeding season and may occasionally forage in the proposed spoil disposal area to the west of the Burford Bank.
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4.3 Assessment of Potential Impact 4.3.1 Dilution and Dispersal Characteristics The proposed dumping methodology is by split bottom barge as described in Section 5.3. This section summarises the assessment of the potential impact of the disposal of the spoil and its dilution and dispersal characteristics.
Behaviour of Material Once the barge hull is opened the contents of the entire hopper are emptied into the water in a matter of seconds. The behaviour of the material during disposal is described as being separated into three phases by US EPA and USACE (1998), and shown in Figure 9:
. Convective descent, during which the disposal cloud falls under the influence of gravity and its initial momentum is imparted by gravity, it falls through the water column as a well defined jet of high density fluid;
. Dynamic collapse, occurring when the descending cloud either impacts the bottom and horizontal spreading dominates; and
. Passive transport-dispersion, when the material transport and spreading are determined more by ambient currents and turbulence than by the dynamics of the disposal operation.
For inspection purposes only. Consent of copyright owner required for any other use.
Figure 9 Behaviour of material during disposal (US EPA and USACE, 1998)
Estimated Settlement Rates and Erosion For the disposal of spoil at sea, an analysis of the settlement rates based on particle size was carried out, where no currents were considered and as if the particles were settling in a container of still sea water. The sinking material is assumed to fall according to Stoke’s law which is based on properties of the particle. The calculations are shown in Appendix E.
Three scenarios were assessed based on the estimated particle size ranges, as described below and displayed in Table 13:
. An average scenario – where the average is calculated based on the range of possible particle sizes and is considered a more typical scenario;
. An upper limit – with a larger portion of smaller particles assumed – the worst case scenario; and
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. A lower limit – with a smaller portion of smaller particles – the best case scenario.
Table 13 Material composition – Upper and lower limit (based on BS 1377-2:1990)
Upper limit Lower limit Material Category Average % % % Small cobbles (< 10cm) 19 10 28 Gravel (> 2mm) 51 40 62 Sand (0.06 – 2 mm) 13 20 6 Silt (0.002 – 0.06 mm) 6 10 2 Clay (< 0.002 mm) 11 20 2
The analysis showed that in an average water depth of 19 m, the percentage of the material that will be on the bottom in less than 15 minutes for each of the scenarios is as follows:
. Average scenario 70 %;
. Worst case scenario 50 %; and
. Best case scenario 90 %.
This material equates to the gravel and cobble portion (greater than 2 mm) that is predicted to reach the bottom within 15 minutes. The sand particles (6-20 %) were estimated to reach the bottom in approximately 1 hour. In reality the sand portion, will likely fall through the water column along with the gravels, as a well defined jet of high density fluid.
In all scenarios the analysis showed that, based solely on the sinking velocities of clay (includes residual bentonite) and silt particles, they may remain in the water column for some time. However, when taking other factors such as tides and currents into consideration it is likely that these particles will become dispersed in the water column after one or more tidal cycles. The slow or non-settling particles will be transported and migrate according to the currents, that is in a north or south direction depending on the tide (refer to Section 4.2.2 Dispersal C haracteristics For inspection), purposesin range only. of some hundred metres to some kilometres. Consent of copyright owner required for any other use. Over a period of time the deposited particles can become re-eroded and transported northward with the current. The particle size determines the erosion velocity based on the Hjulström-diagram for the stability of the seabed subject to current-flow (Smoltczyk, 2002). For example sand particles have an erosion velocity of 0.2-0.4 m/s and for the smaller gravel fraction (> 2 mm) it is between 0.3-0.4 m/s. These velocities are possible for much of the tidal cycle. The larger gravel and small cobbles, which accounts for the bulk of the material, will be less likely to be re-suspended. For example, a particle of 4 mm would require velocities of 0.7-0.8 m/s to become entrained, and these velocities are not common on the seabed at the spoil disposal site (refer to Table 7).
Previous Studies Dowley and Hussey (1998) carried out a modelling study to assess the morphology of dredged material placed on the seabed at the spoil ground west of Burford Bank. They modelled material that was mostly fine silty sand (sand and silt 92 %). It was determined that for the most part the material was mostly retained within the boundaries of the site. This was determined by comparing simulated bathymetries of the spoil ground a year after the spoil was placed, which showed changes over time in the shallower parts of the site but the bathymetries were similar in deeper parts of the site. They also suggested that the presence of the bank itself would tend to protect the spoil from re-suspension from larger waves from easterly directions to some extent.
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An earlier modelling study on the previous Burford Bank site by Irish Hydrodata (1995) assessed the settlement rates of Dublin Ports dredged material which consisted of silty sand material (sand and silt 92 %). For each of the tidal simulations modelled (on both spring and neap tides) the settlement results were found to be similar; with the sand fraction settling very rapidly within 500 seconds of discharge while for the silt and clay fraction between 1 and 1.5% of the material was still in suspension after 4 hours. The horizontal distribution of settled material on the spoil ground was found to be closely related to the disposal pattern due to the speed at which it settles out.
Both of these studies reveal that the spoil is largely contained in the spoil ground. The material they modelled had a much higher percentage of fine material (sand and silt 92 %) in comparison to this proposal for dumping at sea which is predominantly gravel material (51 %) with the sand and silt portion adding up to approximately 19 %.
4.3.2 Cumulative Effects of Current and/or Previous Dumping in the Area The proposed spoil disposal site is currently permitted to Dublin Port Company (DPC) (EPA Reg No. S0004- 01). DPC proposes to dump an estimated volume of 1,875,000 m3 over a six year period. 2012 was year 1 of their 6 year programme. DPC were consulted and said that a single dredging operation is carried out approximately once every two years on average. Each single dredging operation involves a split bottom trailer suction barge of about 1,000 m3 capacity loading up and dumping at the spoil disposal area. The operation involves a 5 times per day for 7 days per week for three weeks dumping operation at the Burford Bank.
It is likely that this proposed dumping operation will overlap with DPCs dumping operations. It is not predicted that there will be any cumulative effects as a result of the proposed operation as the overlap will only be for a three week period and will only add one extra load to what DPC will be dumping. DPC have confirmed that the proposed dumping operations and programme will not have any adverse impact on their daily marine operations in Dublin Bay. The proposed dumping operations will be coordinated with DPC operations to target different areas of the spoil disposal area during this period.
The impacts of previous dumping on ecology was studied by Kennedy (2008), who carried out a baseline benthic ecological assessment for DPC. The overall conclusion was that the dumping site appears to have For inspection purposes only. recovered well from previous dredgingConsent events of copyright and to owner be capable required for of any receiving other use. further spoil.
4.3.3 Potential Impacts on Ecology Natura Environmental Consultants were commissioned to undertake a Screening for Appropriate Assessment for the proposed loading and spoil disposal and the report is contained in Appendix F. It examined the likely effects of a project either alone or in combination with other projects upon Natura 2000 sites and considers whether it can be objectively concluded that these effects will not be significant.
Natura Environmental Consultants carried out a desk study to collate available information on the ecological environment. The National Parks and Wildlife Service (NPWS) database was consulted concerning designated conservation areas and their conservation objectives.
This section briefly summaries the findings of the Screening for Appropriate Assessment, refer to Appendix F for a full technical report.
Potential indirect impacts of the increase of suspended sediments and migration of spoil Based on the assessment contained in Section 4.3.1 Dilution and Dispersal Characteristics, it is predicted that the volumes of suspended materials reaching the Natura 2000 sites in the intertidal parts of Dublin Bay are likely to be extremely small and probably not measurable. The main tidal currents in the area of the Burford Bank are in a north-south direction, away from the intertidal areas of Dublin Bay. Additionally, the
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dominant flow in this part of the Irish Sea is northwards and fines will therefore be moved away from the Kish Bank and will eventually settle out in the northern Irish Sea.
Potential indirect impacts of smothering of macrobenthos As noted above, it is predicted that the volumes of suspended materials reaching the Natura 2000 sites in the intertidal parts of Dublin Bay are likely to be extremely small and probably not measurable. As current patterns in the area are to a great extent north south, the likelihood of any significant levels of suspended sediments reaching the inner parts of Dublin Bay (Bull Island SPA and South Dublin and Tolka Estuary are 3.4km and 5.7km respectively) is seen as extremely low. Fines will not settle around the Kish Bank but will be transported northwards by the current and will eventually settle out in the northern part of the Irish Sea.
Potential indirect impacts of smothering of fish spawning and nursery habitats The spawning and nursery grounds in the Irish Sea extend over a larger portion of its northern sector and it is considered that the fine particles settling out from the disposal activities will be a very small fraction (e.g. less than 1%) of the total area of these habitats and therefore will not impact them.
Potential indirect impacts on foraging areas for seabird and marine mammal species It was determined that there would likely be indirect effects from the proposed spoil disposal which would be to make this area unsuitable for foraging seabirds and marine mammals for temporary periods, immediately after each discharge of spoil material. The area of the proposed disposal site is approximately 210 ha and it ranges in depth from 12.5 m to 24 m CD, with an average depth of 19 m CD. This is significantly deeper than the northern end of the Kish Bank which ranges from approximately 1 m to 16 m in depth. The proposed disposal site may thus be less suitable for foraging terns compared to the shallower banks elsewhere in the general area.
While Grey Seals are listed as a qualifying interest for Lambay Island cSAC, the occurrence of these mammals in the affected area is likely to be very limited in normal circumstances. None of the cetacean species recorded in the Dublin Bay area is listed as a qualifying interest of any Natura 2000 sites within the vicinity of the proposed Burford Bank spoil disposal area.
Potential formation of a subtidal cobble reef The deposition of cobbles and small stones will give rise to areas of subtidal reef habitat on the surface of For inspection purposes only. the seabed, that will be colonised byConsent a variety of copyright of invertebrates owner required for which any other in use. turn will act a food resource for a variety of species such as crab, lobster, conger, pollack and ling. As it is a designated spoil ground, bottom trawlers do not fish the site and the young adults of the commercial fish species will move away from the site over time thereby enhancing the local fishery. The area may become a popular angling site over time. This will be a positive benefit to foraging seabirds and marine mammals in the medium to long term, providing a refuge where trawling cannot take place.
Potential indirect impacts from the loading of spoil at the Pigeon House Jetty With regard to disturbance to waterbird populations during construction; all construction activity will be land based, with the exception of the marine diffuser construction. Access will be from the existing Pigeon House Road which is already subject to normal vehicle and pedestrian traffic. Recent sand accumulation and development of embryonic shifting dune habitat provides a degree of separation from intertidal areas used by waterbirds on Sandymount Strand. Waterbird use of the intertidal area immediately to the east of Irishtown Nature Park is very low. This small area, between the developing sand bar and the rock-armoured shore at Irishtown Nature Park, is already heavily disturbed by amenity use, mainly walkers and dogs. It is not considered that loading activities will have any adverse impact on waterbird use of the intertidal areas within South Dublin Bay SPA.
The loading of spoil into a vessel moored at the Pigeon House Jetty will generate noise that could potentially affect the breeding colony of Common Terns and Arctic Terns that is present on the neighbouring ESB
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mooring dolphin, during the months of May to August each year. However, these terns have habituated to a high level of disturbance from passing shipping each day and would not be disturbed if there is no contact between the vessel and the mooring dolphin. Terns are not normally disturbed by construction noise and have habituated to existing industrial noise in the Dublin Port area. Contrary to prevailing opinion, there is little scientifically acceptable evidence that human disturbance causes substantial harm to nesting terns. Although there are no formal studies of habituation, many or most colonial waterbirds can become extremely tolerant of repeated human disturbance (Nisbet 2000).
It is considered that, the construction works relating to the loading of spoil will not adversely affect the integrity of any of the Natura 2000 sites listed above.
Screening assessment conclusions The screening assessment (Appendix F) concluded that the proposed loading and disposal of spoil will not have a significant adverse affect, either directly or indirectly on the integrity of North Dublin Bay cSAC, North Bull Island SPA, South Dublin Bay cSAC, South Dublin Bay and River Tolka Estuary SPA, Howth Head cSAC, Howth Head Coast SPA, Ireland’s Eye cSAC, Ireland’s Eye SPA, Skerries Islands SPA, Dalkey Islands SPA or Bray Head cSAC.
4.3.4 Potential Impacts on Marine Uses and Resources This section describes the potential impacts on other marine uses and resources, including fishing, recreation, shipping, pipelines and cables, mineral extraction and desalination.
Refer to Section 5.1 for a discussion of these marine uses and resources with respect to the site selection of the Burford Bank spoil disposal area and Figure 11 which shows their location and extent within Dublin Bay.
Environmental Protected Areas Refer to Section 4.2.4 for a summary of the environmental protected areas and a full description is contained in Appendix F.
Fishing Presently commercial fishing activities in Dublin Bay are limited. The major fishing port is at Howth Harbour and there is also fishing carried out at Dun Laoghaire Harbour. Very little of the fish catch arises within For inspection purposes only. Dublin Bay itself. Dublin Bay from HowthConsent Head of copyright to Dalkey owner Island required isfor a any no other trawl use. zone and so there is no activity such as trawling or dredging (D. Rehan, Bord Iascaigh Mhara (BIM), pers. comm.). Potting for lobster and velvet crab is the main activity in the south of the Bay and it is seasonal, however there are only a few pots located sporadically. Line fishing is permitted throughout the Bay.
The boundaries for areas where different methods of fishing are commonly used were obtained from the Marine Institute from their Inshore Fisheries Atlas.
Refer to Section 4.2.4 for a description of fish stocks, spawning and nursery areas and the potential impacts are summarised in Section 4.3.3.
Recreation and amenity areas Dublin Bay is a high amenity area with a number of scenic views, walkways, natural interest areas and beaches. Throughout the year significant numbers of people use the amenity of the bay, particularly at Howth Head, Bull Island, Clontarf, Sandymount, Dun Laoghaire and Seapoint. Popular water based activities in Dublin Bay include sailing, angling, swimming and water sports such as scuba diving, wind surfing, kite surfing and sea kayaking. In the Dublin Bay Water Quality Management Plan (1991) recreation and water sports areas within the Bay are delineated and the areas cover virtually the entire coastline in the Bay area.
Sailing is also a major coastal activity in the Dublin area. There are several clubs in Dublin Bay which are engaged in the organisation of sailing and/or leisure boating activities for their members. Dublin Bay Sailing
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Club lays yacht racing marks within the Dublin Bay that cover an area extending from Salthill and Seapoint on the western side of the bay to near the Burford Bank on the east. The racing season usually starts at the end of April and continues up to the end of September.
There are several popular recreational beaches used in Dublin Bay by locals and day-trippers. Under the Quality of Bathing Waters Regulations, 1992 (S.I 155 of 1992) and amendments, four stretches of beach have been designated as bathing water protected areas within Dublin Bay:
. Dollymount Strand;
. Sandymount Strand;
. Merrion Strand; and
. Seapoint.
There is no significant recreational or amenity activity anticipated in the Burford Bank spoil disposal area as the main areas are closer to the coast as shown on Figure 11 in the following section. Any local increases in residual suspended solids levels as a result of the proposed disposal at sea are unlikely to impact upon recreational uses of the bay.
Shipping Maritime traffic is busy in Dublin Bay as it is home to Ireland’s largest port. It accounts for 50 % of all Ireland’s imports and exports as well as being a major passenger port. Navigational channels which enter Dublin Bay to the north and south of Burford Bank meet at a central roundabout buoy and then lead to Dublin Port via a dredged channel of 7.8 m maintained depth.
The Burford Bank spoil disposal area is outside of any navigational channels and to the west of Burford Bank which is avoided by mariners. Dumping of spoil in this area will have no impact on shipping. DPC have confirmed that the proposed dumping operations and programme will not have any adverse impact on their daily marine operations in Dublin Bay.
Archaeology and Shipwrecks A desk-based assessment utilising the Record For inspection of Monuments purposes only. and Places, the National Museum of Ireland Consent of copyright owner required for any other use. Topographical Files, the Dublin City Development Plan 2011-2017, documentary and cartographic sources was undertaken as part of the environmental impact statement (refer to Chapter 15) for the Ringsend WwTW Extension Project.
Figure 10 shows the archaeological areas and the protected structures in the vicinity of the Pigeon House Jetty. Pigeon House Dock is itself designated as a conservation area. Conservation areas are designated in recognition of their unique contribution and importance to the heritage of the city. Dublin City Council seeks to ensure that proposals for developments within conservation areas complement the character of the area, including the setting of protected structures, and comply with development standards.
The use of the Pigeon House Jetty for loading operations is in keeping with the previous use of the jetty for loading of waste water sludge onto barges for dumping at sea. There will be a buffer of at least 3 m between the proposed loading area and the Pigeon House Dock Conservation area (refer to Appendix A Figure A.1). It is considered unlikely that any structural changes to the jetty should be required for the purposes of the loading operations, however, in the event of any structural works being proposed for the purposes of strengthening the jetty, a full archaeological and architectural heritage assessment will be carried out and approval of the National Monuments Service of the Department of Arts Heritage and the Gaeltacht will be sought.
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Conservation areas
Pigeon House Jetty
Recorded Monuments and Places
Pigeon House Jetty
Record of Protected Structures
Pigeon House Jetty For inspection purposes only. Consent of copyright owner required for any other use.
Figure 10 Archaeological areas in the vicinity of Pigeon House Jetty (extract from Chapter 15 EIS)
An assessment of the potential for shipwrecks within the spoil disposal area itself was also carried out. Shipwreck information was obtained from three sources, which include:
. Under water Archaeology Unit (UAU) of the Department of Environment Heritage and Local Government (DEHLG) - have produced an Inventory of Recorded Shipwrecks for the East Coast of Ireland. The UAU manage and update the Shipwreck Inventory of Ireland. This is the most comprehensive and accurate dataset, which includes all known wrecks for the years up to and including 1945. The Shipwreck Inventory is principally a desktop survey with information gathered from a broad range of cartographic, archaeological and historical sources, both documentary and pictorial;
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. INFOMAR – have been able to identify possible shipwrecks and from their multibeam marine mapping. This has been a co-operative effort between GSI and the UAU; and
. Admiralty Chart - published by the UKHO, contains the location of some wrecks.
There are no recorded shipwrecks within the vicinity of the spoil disposal area.
Engineering uses of the sea such as undersea cables and pipelines etc. Pipelines and cables are marked on the Admiralty Chart of Dublin Bay (1415).
. There are two active telecommunications cables within Dublin Bay.
. There are two cross bay sewerage pipelines. One carries sewage from the Sutton pumping station in the North of Dublin to Ringsend WwTW and one carries sewage from the West Pier pumping station in Dun Laoghaire Rathdown to the Ringsend WwTW.
. There is a high pressure gas main that runs into the ESB site at Poolbeg. The pipeline is not in fact shown on the Admiralty chart.
There are no pipelines or cables recorded within the Burford Bank spoil disposal area.
Mineral extraction The Department of Environment, Community and Local Government is responsible for licensing aggregate and mineral extraction developments on the foreshore under the Foreshore and Dumping at Sea (Amendment) Act 2009. There are no active or proposed marine aggregate licences in Ireland.
Desalination Ten water supply options were assessed for their potential to meet the future water supply needs in a sustainable manner for the Dublin Region. Desalination was one of the options studied and it was determined to be technically feasible as a major water supply option which has the capacity to deliver a high quality, sustainable product capable of secure operation with the necessary flexibility to meet changes in demand and water quality standards during the life of the project. However, high energy consumption entails high installed power capacity demand charges. As a consequence the anticipated CO2 emissions from For inspection purposes only. a plant powered by the national gridConsent would of copyrighthave a ownerconsiderable required for anynegative other use. impact on the environment compared to non-desalination technologies. Dublin City Council (2008). In October 2010 Dublin City Council adopted the Water Supply Project-Dublin Region Plan (amended 2008 draft Plan) containing the recommended option. The recommended option involves the abstraction of raw water from Lough Derg (River Shannon) and pumping the abstracted water through a new pipeline to a proposed storage reservoir covering approximately 1,400 acres (567 hectares) at the Garryhinch cut-away bog (near Portarlington, Co. Laois), forming part of a proposed midlands water based eco-park. The water will be treated to drinking water standards at this location and the treated water transported in a series of pipelines to the Dublin Region Water Supply Area with provision for local supplies. (Dublin City Council, 2012).
Therefore as there are no existing or proposed desalination projects in Ireland, the proposed dumping at sea will have no impact on desalination.
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Section 5 Dumping Operations (Section E)
5.1 Site Selection (E.1) The proposed site for disposal of spoil from the tunnel is the spoil ground west of Burford Bank in Dublin Bay, as shown in Appendix Figure A.3. The nearest shore is Baily at Howth which is approximately 3 km away from the dump site at its closest point. The bathymetry of the site is described in Section 4.2.2. The site has been used since 1996 for disposal of maintenance and capital dredging works, and Dublin Port Company (EPA Reg No. S0004-01) and Howth Yacht Club (EPA Reg No. S0010-01) currently have permits to dump at the site. There are no other disposal sites in the vicinity of Dublin Bay and the nearest disposal site is permitted to Drogheda a significant distance from Ringsend and it would be impractical to use this option.
An assessment of the location of the spoil disposal area in relation to potential constraints in Dublin Bay was also carried out. All the known potential constraints were compiled onto one map of Dublin Bay as shown in Figure 11. As can be seen from the map the only known potential constraints within the spoil disposal area is the fishing areas, however these are simply the boundaries for areas where different methods of fishing are commonly used. Each of the relevant constraints to the dumping of spoil in the selected site (including fishing areas) and the data sources are discussed in detail in Section 4.3.4.
For inspection purposes only. Consent of copyright owner required for any other use.
Figure 11 Constraints for site selection of spoil disposal area
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5.2 General Information about the Proposed Spoil Disposal Area (E.2) 5.2.1 Details of Previous Dumping at the Site (E.2 (I)) The proposed spoil disposal area has been used since 1996 for the disposal of dredge material from maintenance dredging operations by Dublin Port Company. They dumped approximately 96,000 tonnes per annum in 1999, 2000, 2003, 2006, and 2008. The site is currently permitted to Dublin Port Company (EPA Reg No. S0004-01). Dublin Port proposes to dump an estimated volume of 1,875,000 m3 over a six year period, including contingency and on the basis of 5 dredging operations.
The site is also currently permitted to Howth Yacht Club (EPA Reg No. S0010-01) for the disposal of a maximum of 120,000 tonnes of dredged material which will be 72 % rock/ gravel.
Other dumping at the site included capital works for the Dublin Bay pipeline, which also used the site for disposal from 1996 to 1998 and also for dumping of a total of 300 tonnes of spoil daily from Macken Street Bridge (2nd June 2009 to 31st October 2009) on behalf of Dublin City Council in 2009 (Permit No. 384).
Previous studies on the impact of the dumping operations on the environment Pre-Dredging Sediment Assessment - Burford Bank, Kennedy, 2008 – prepared by Moore Marine and Atlantic RMS for Dublin Port Company and is contained in Appendix I of the Dublin Port Company Dumping at Sea application (S0004-01). The main points of the study were:
. A baseline benthic ecological assessment was carried out with the aim of verifying that the site had recovered from previous disposal activities and was fit to receive the Dublin Ports planned spoil disposal;
. Sediment analyses revealed that the bottom types are typical of Irish coastal waters, being muds and muddy fine sand of low organic content. The macrobenthic communities are typical of these habitat types and their distribution appears to be accounted for by changes in grain size distribution in the area using both multivariate and univariate methods; and
. Overall it was concluded that the dumping site appears to have recovered well from previous For inspection purposes only. dredging events and to be capableConsent of of copyright receiving owner further required forspoil. any other The use. clear mitigation measure necessary
is to ensure that any spoil disposed of at the site is spread evenly around the disposal area, and that no particular area receives too large a volume of spoil for water currents and macrobenthos to oxidize. 5.3 Details of Method and Rate of Disposal (E.2 (VI)) The disposal methodology will be using a self-propelled split bottom barge, where the hull of the whole barge splits longitudinally between the end bulkheads. The exact specifications of the vessel to be used will be dependent on the outcome of the tendering process. It is estimated that a typical load would be approximately 1,000 m3 and disposal at sea is likely to occur on average less than once per day and no more than twice per day, for a period of up to 3 years (refer to Section 2.3.3).
Accurate split hopper barge positioning using a grid system will be used to drop the material within a defined area working on a pre-defined grid system. It is expected that the bulk of the rock material will reach the sea bed in less than 15 minutes and settle close to the site of dumping. Due to turbulence during the fall some of the smaller particles will be dispersed in the water column and the settling rates depend on their individual characteristics (refer to Section 4.3.1).
With the risk of rock/ gravel being transported beyond the perimeter of the spoil disposal area as it settles to the seabed being low it is proposed dispose of the rock material over the entire area of the spoil disposal
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area. If the spoil was to be uniformly spread over the entire area of the spoil disposal ground it would only raise the seabed level by approximately 26 cm.
The contractor will be required to submit a dumping plan that will include methodologies to limit mounding on the seabed. The bottom doors of the barge can be opened slowly to allow the rock to trickle out over an area. The direction of the tides will be incorporated into the plan.
Note that no packaging and containment of the spoil is required as the spoil is inert uncontaminated material.
For inspection purposes only. Consent of copyright owner required for any other use.
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Section 6 Monitoring (Section F)
No dredging proposed for this project in turn no monitoring of the loading sites are proposed and therefore there is no requirement for monitoring points. Monitoring of the dumping site however is proposed, which will include pre and post bathymetric surveys and a dumping activity log, as outlined in this section. 6.1 Bathymetry The contractor will be required to undertake pre and post bathymetric survey of the entire spoil disposal area to compare and record any changes to the seabed level.
Quarterly bathymetric surveys of selected locations of the spoil disposal area are also proposed. These will be used to ensure that the dumping is carried out in conformance with the dumping plan and in turn to assess the effectiveness of the dumping plan to allow any revision as necessary to ensure that the spoil is spread across the designated area effectively and in turn the plan can be revised to reduce any impact on the seabed, if required. 6.2 Dumping Activity Log Information relating to the dumping activity shall be recorded during each dumping voyage and shall include, as a minimum:
. The name of the vessel;
. The date, time, location and position at which the voyage for the purposes of dumping began, dumped the spoil and ended;
. The quantity in metric tonnes of the material dumped and nature of the material;
. A logged vessel track record, vessel speed, etc.; and For inspection purposes only. Consent of copyright owner required for any other use. . Weather conditions and stage of the tide.
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Section 7 Summary
The alternatives for the spoil were investigated by the project team, in accordance with the waste hierarchy, including; infill material for roads and coastal protection, land reclamation projects, production of aggregate, quarry restoration and disposal at sea. It was determined that there were two viable options for the spoil, the first quarry restoration and the second sea disposal. Quarry restoration is considered a recovery activity under the waste hierarchy and as such it is considered more favourable than disposal at sea, as disposal should be the last resort. Under the OSPAR Convention the dumping of inert materials at sea of natural origin is permitted.
The economic and environmental benefits to the disposal at sea option were researched. The routes to the quarries are a significant distance from Dublin and will generate traffic volumes on the national road
network. Also it was estimated that the total CO2 emissions per tonne-km for all of the truck or barge trips i.e. for the duration of the project (approx 3 years), that the CO2 emissions for the barge option was
significantly less and only equated to 5% of the estimated CO2 emissions as compared to the truck option.
Under the OSPAR (1998) Guidelines for the Management of Dredged Material, previously undisturbed geological material is exempt from detailed characterisation which includes chemical and biological. It was also confirmed that no material testing was required, through discussions with the Marine Institute, the EPA and the RPII.
The proposed site for disposal of spoil from the tunnel is the spoil ground west of Burford Bank in Dublin Bay. The site has been used since 1996 for disposal of maintenance and capital dredging works and is currently permitted to Dublin Port Company and Howth Yacht Club. The potential impacts on other marine uses and resources, including fishing, recreation, shipping, pipelines and cables, mineral extraction and desalination where examined. It was concluded that the disposal area had no known constraints to the proposed dumping operation and in turn would have no impact on marine uses and resources.
Natura Environmental Consultants were commissioned For inspection purposes to undertake only. a Screening for Appropriate Assessment for the proposed loading Consentand spoil of copyright disposal owner which required examined for any other theuse. likely effects of a project either
alone or in combination with other projects upon Natura 2000 sites and considers whether it can be objectively concluded that these effects will not be significant. The screening assessment concluded that the proposed loading and disposal of spoil will not have a significant adverse affect, either directly or indirectly on the integrity of North Dublin Bay cSAC, North Bull Island SPA, South Dublin Bay cSAC, South Dublin Bay and River Tolka Estuary SPA, Howth Head cSAC, Howth Head Coast SPA, Ireland’s Eye cSAC, Ireland’s Eye SPA, Skerries Islands SPA, Dalkey Islands SPA or Bray Head cSAC.
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Section 8 References
Berrow, S.D., Hickey, R., O’Brien, J. O’Connor, I. and McGrath, D. (2008) Harbour Porpoise Survey 2008. Report to the National Parks and Wildlife Service. Irish Whale and Dolphin Group. pp.33.
Cefas (2006). Dose assessments in relation to disposal at sea under the de minimis radioactivity’ For DEFRA Project AA005.
DEFRA (2012). 2012 Guidelines to Defra / DECC’s GHG Conversion Factors for Company Reporting: Methodology Paper for Emission Factors. July 2012. PB 13792.
Dowley, A and Hussey, M. (1998). Burford Dump Site Modelling Study. Centre for Water Resources Research, Department of Civil Engineering, University College Dublin. November 3 1998.
Dublin City Council (2008). Desalination Study Report. Water Supply Project – Dublin Region. November 2008.
Dublin City Council (2012). Ringsend WwTW Extension Environmental Impact Statement.
Dublin City Council (2012). Water Supply Project - Dublin Region. Website
Environmental Protection Agency (2010). Water quality in Ireland 2007-2009. M. McGarrigle, J. Lucey and M. O’Cinnéide (Eds). Chapter 5: Quality of estuarine and coastal waters. pp. 105-127.
Environmental Protection Agency (2011). Dumping at Sea Permit Application Guidance Note. EPA, Wexford.
For inspection purposes only. INFOMAR (2010). Seabed ClassificationConsent Chart of copyright for the owner East required Coast for. anyINFOMAR other use. Programme East Coast – Acoustic seabed classification. Revision 2 February 2010.
Irish Hydrodata Limited (1995). Characterisation of Burford Bank Dredge Spoil Disposal Site. Appendix L of Dublin Port Company Dumping at Sea Permit. Unpublished report prepared for Department of Marine.
Kennedy, R. (2008). Pre-Dredging Sediment Assessment of the Burford Bank, Dublin on behalf of Dublin Port. Prepared by Moore Marine Services and Atlantic Resource Management Solutions on behalf of Jacobs Engineering. pp. 40. Appendix I of Dublin Port Company Dumping at Sea Permit.
Lordan, C. and Gerritsen, H. (2009). Marine Institute. Working Document on the Assessment of the "Irish Box"
Marine Institute (2011). The Stock Book. Report to the Minister for Agriculture, Fisheries and Food Annual Review of Fish Stocks in 2011 with Management Advice for 2012. Fisheries Science Services. November 2011.
Met, 2012. Marine - Climatology. Website http://www.met.ie/marine/marine_map.asp>. Visited 20th August 2012.
Newton, S.F. and Crowe, O. (2000). Roseate Terns – The Natural Connection. Maritime Ireladn/Wales INTERREG Report No. 2. The Marine Institute, Dublin.
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Nisbet, I.C.T. (2000). Disturbance, Habituation, and Management of Waterbird Colonies. Waterbirds: The International Journal of Waterbird Biology 23, 312-332.
Ó Cadhla, O., Strong, D., O’Keeffe, C., Coleman, M., Cronin, M., Duck, C., Murray, T., Dower, P., Nairn, R., Murphy, P., Smiddy, P., Saich, C., Lyons, D. and Hiby, A.R. (2007). An assessment of the breeding population of grey seals in the Republic of Ireland, 2005. Irish Wildlife Manuals No. 34. National Parks & Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.
Oates, J.A.H. (1998). Lime and Limestone – Chemistry and Technology, Production and Uses. Whiley-VCH.
OSPAR (1998). OSPAR Guidelines for the Management of Dredged Material (Reference 1998-20). Ministerial Meeting of the OSPAR Commission Summary Record OSPAR 98/14/1-E, Annex 43.
Smoltczyk, U. (2002). Geotechnical Engineering Handbook. Volumes 1 - 3. John Wiley & Sons.
UKHO (2012). Admiralty Tide Tables. United Kingdom and Ireland. Vol 1 2012.
US EPA and USACE (1998). Evaluation of Dredged Material Proposed For Discharge in Waters of the Testing U.S. Army Corps (Inland Testing Manual). Appendix C Evaluation of Mixing.
Walker, A.J.M. and Rees, E.I.S. (1980). Benthic fauna and sludge dumping in Dublin Bay. Irish Fisheries Investigations Series B. No. 22 (1980) pp. 59.
Wheeler, A.J., Walshe, J. and Sutton, G.D. (2000). Geological Appraisal of the Kish, Burford, Bray and Fraser Banks, Outer Dublin Bay Area. Marine Institute.
For inspection purposes only. Consent of copyright owner required for any other use.
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Appendix A Figures and Drawings
For inspection purposes only. Consent of copyright owner required for any other use.
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EPA Export 10-12-2012:23:36:44 Legend Proposed Diffuser Site Loading Area Proposed Spoil Disposal Area (Spoil Ground) Tunnel Construction Compound (ESB Site)
Latitude Longitude ITM (a) 53° 19' 45.331" -6° 3' 11.040" E729685, N732768 (b) 53° 19' 45.322" -6° 3' 10.500" E729695, N732768 (c) 53° 19' 45.999" -6° 3' 10.515" E729695, N732758 (d) 53° 19' 45.007" -6° 3' 11.055" E729685, N732758
Pigeon House Jetty
Location of Proposed (a) Diffuser Site Loading Area
For inspection purposes only. Consent of copyright owner required for any other use.
Proposed Diffuser Site Loading Area
(a) (b) ! ! A A Diffuser Shaft
(d)A! A! (c) Proposed Long Sea Outfall Tunnel Meters 0 105
© Copyright Ringsend WwTW Extension Project This drawing and any design hereon is copyright and should not be reproduced without the owner permission. Drawn by: DAG Kilometers Date: 19/11/2012 Figure A.2: Source: 0 0.5 1 2 3 4 5 Internal Project Reference: 4 © British Crown and SeaZone Solutions Limited. Diffuser Shaft Loading Area All rights reserved. \\Erbdgis\gis\CURRENT_PROJECTS\75461_Ringsend_Tunnel\ Products Licence No. 012010.005 02_GIS_Tasks\23_EPALicenses\MXD\11_Loading2Loc.mxd Scale 1:50,000 @A3 (Ref B.3)
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(d) Legend Proposed Spoil Disposal Area (Spoil Ground) Tunnel Construction Compound (ESB Site)
Latitude Longitude ITM (a) 53° 20′ 5′′ -6° 3′ 3′′ E729824, N733371 (b) 53° 20′ 5′′ -6° 1′ 53′′ E731109, N733412 (c) 53° 19′ 11′′ -6° 1′ 52′′ E731170, N731750 (d) 53° 19′ 11′′ -6° 2′ 46′′ E730180, N731714 (e) 53° 19′ 24′′ -6° 3′ 3′′ E729855, N732102
(a) (b)
(e)
For inspection purposes only. (c) Consent of copyright owner required for any other use. (d)
Meath
Dublin
Kildare Wicklow
© Copyright Ringsend WwTW Extension Project This drawing and any design hereon is copyright and should not be reproduced without the owner permission. Drawn by: DAG Kilometers Date: 19/11/2012 Figure A.3: Source: 0 0.5 1 2 3 4 5 Internal Project Reference: 4 © British Crown and SeaZone Solutions Limited. Location of Spoil Disposal Area All rights reserved. \\Erbdgis\gis\CURRENT_PROJECTS\75461_Ringsend_Tunnel\ Products Licence No. 012010.005 02_GIS_Tasks\23_EPALicenses\MXD\03_DisposalLoc.mxd Scale 1:50,000 @A3 (Ref E.2 (II))
EPA Export 10-12-2012:23:36:44 -25 -25 -15 -20 -30Legend -30 -25 -25 -25 Spoil Disposal Area -25 -30 -25 -30Bathymetric contours at 5.0 metre intervals -25 -30(OD (Malin Head) Datum)
-25 -30 -20 Bathymetry (Fugro, 2010) metres below OD (Malin Head) Datum
Value -30 -30 -30 -25 High : 2.42982 -25 -20 -20 Low : -39.65 -25 -20 Spoil Disposal Area -20
-20-20 -20 -15
-20
-20 -25 Ref: Fugro (2010) Ringsend WwTW Extension Project Burford - Marine Site Investigation -20 Dublin Bay Ireland Bank Survey Period: 28th October 2010 – 26th For inspection purposes only. March 2011 Consent of copyright owner required for any other use. Fugro Volume 1 of 9: Bathymetric Survey Report-25
-25 Meath
-25
-10 -20 -15
Dublin -25
-25 -25
-20 Wicklow Wicklow -25
-10 -15
Drawn by: LG Ringsend WwTW Extension Project Date: 19/11/2012 © Copyright Kilometers This drawing and any design hereon is copyright and should not be reproduced without the owner permission. Internal Project Reference: 0 0.125 0.25 0.5 0.75 1 4 Figure A.4: Bathymetry of Spoil \\Erbdgis\gis\CURRENT_PROJECTS\75461_Ringsend_Tunnel\ 02_GIS_Tasks\23_EPALicenses\MXD\02_Bathymetry.mxd Disposal Area
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Appendix B Tunnel Spoil Disposal Study 2011
For inspection purposes only. Consent of copyright owner required for any other use.
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Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study
Document Control Sheet
Client Dublin City Council Project Ringsend WwTW Effluent Outfall Extension Report Tunnel Soil Disposal Study Date June 2011 Project No: 75461
Document Reference DG 34 – Draft 02
Version Author Reviewed Checked Date
Draft 01 Kieran O’Dwyer Ken McIntyre Anthony Kerr June 2011
Ken McIntyre/Bob Draft 02 Kieran O’Dwyer Anthony Kerr June 2011 Gaudes
Distribution Copy No. For inspection purposes only. Master (CDM) Consent01 of copyright owner required for any other use. DCC 02,03,04
© 2011 CAMP DRESSER & MCKEE ALL RIGHTS RESERVED Reuse of Documents: These documents and designs provided by professional service, incorporated herein, are the property of CDM and are not to be used, in whole or part, for any other project without the written authorization of CDM.
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Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study
Table of Contents SECTION 1 INTRODUCTION ...... 1 SECTION 2 WASTE MANAGEMENT LEGISLATION ...... 3 2.1 Waste Classification of Spoil...... 3 2.2 The Waste Hierarchy ...... 6 2.3 Disposal ...... 7 2.4 Contract Provisions ...... 8 SECTION 3 SITE INVESTIGATION RESULTS AND BEDROCK GEOLOGY . ERROR! BOOKMARK NOT DEFINED. SECTION 4 POTENTIAL CONSTRUCTION METHODS...... 12 4.1 On Shore Access Shaft ...... 12 4.2 Long Sea Outfall Tunnel Section ...... 12 4.3 Diffuser ...... 13 SECTION 5 SPOIL COMPOSITION...... 14 SECTION 6 SPOIL QUANTITIES...... 15 SECTION 7 DISPOSAL OPTIONS ...... 17 7.1 Potential Uses ...... 17 SECTION 8 DISPOSAL TRANSPORT OPTIONS ...... 23 8.1 Removal by truck ...... 23 8.2 Removal by Sea ...... 24 SECTION 9 COSTS ...... 26 For inspection purposes only. Consent of copyright owner required for any other use. 9.1 Haulage Costs by Road to Licensed Facility ...... 26 9.2 Gate Charges Licensed Facility ...... 26 9.3 Overall Cost - Transport and Disposal to Licensed Soil Recovery Facility .. 27 9.4 Transport by Sea (Dumping at Sea or Rosslare Port Reclamation) ...... 27 9.5 Hazardous Waste for Export to Continent ...... 28 9.6 Summary of Spoil Disposal Cost Estimates ...... 28 SECTION 10 SUMMARY AND RECOMMENDATIONS ...... 29 10.1 Summary of Main Findings ...... 29 10.2 Possible Actions ...... 30 10.3 Recommendations ...... 33
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Section 1 Introduction
Dublin City Council (DCC) intends to upgrade the Ringsend Wastewater Treatment Works (WwTW) to meet the future demand projected for the catchment area and to ensure compliance with relevant legislation. The plant is presently experiencing periodic loading in excess of capacity. The plant will be upgraded from its present capacity of 1.64 million population equivalents (PE) to a firm design capacity of 2.1 million PE.
The proposed final treated effluent discharge option is to construct a new long sea outfall (LSO) to discharge the treated effluent at an offshore location. A number of LSO offshore discharge locations were reviewed and marine surveying and marine modelling was undertaken to establish a preferred discharge location. The current preferred LSO discharge location (B3) is shown in Figure 1.
For inspection purposes only. Consent of copyright owner required for any other use.
Figure 1
Figure 1: Modelled LSO offshore discharge locations and preferred discharge location B3. Appropriate Assessments of the outfall discharges at each of the selected outfall locations were carried out under Article 6 of the Habitats Directive 92/43/EEC. The Appropriate Assessments concluded that there would be changes in water quality in the immediate near field mixing zone vicinities for each of the selected outfall locations, but that no significant impacts were predicted outside the near field mixing zone or on any Natura 2000 site in Dublin Bay. In fact, by diverting the existing final treated effluent discharge location from the Liffey River Estuary at Poolbeg to a LSO offshore discharge location terminus outside of the Liffey River Estuary, water quality within the estuary and the inner bay, where Natura 2000 sites and bathing waters are located, will improve.
An extensive subsurface marine site investigation (Marine SI) is currently being carried out to determine the geology along preferred LSO tunnel routes. This Marine SI involves sinking 21 boreholes within the Poolbeg Peninsula and throughout the marine waters of Dublin Bay. Additionally, a geophysics testing programme has been undertaken throughout large parts of the
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Bay. Depending on the results of the Marine SI and various environmental studies, the current preferred LSO discharge location may change.
The results of the marine SI investigation programme and extensive water quality modelling will further assist in identifying the optimal route and final discharge location for the LSO tunnel. The WwTW extension and discharge location will undergo a full Environmental Impact Assessment (EIA) to assess potential impacts from the proposed development and specify any mitigation measures necessary.
The LSO tunnel section and associated inlet and outlet shafts excavations will generate large volumes of spoil. Additional spoil will also be generated from the construction of the upgrade to the Ringsend WwTW. However, this report will address only those excavation quantities associated with the LSO tunnelling contract.
For the purposes of this report the following assumptions in relation to the LSO tunnel and shafts have been made.
The tunnel section is 9.0 km in length.
The finished internal diameter will be 5.0 metres (the bored external diameter is assumed to be 6.5 metres.
The tunnel will be bored through bedrock (apart from the inlet and outlet shafts).
The excavated inlet shaft diameter will not exceed 20.0 metres
The excavated inlet shaft depth will not exceed 110 metres
The cumulative cross sectional areas of the excavated outlet shaft/s will be equivalent to a single shaft with an external diameter not exceeding 6.0 metres
The excavated outlet shaft depth will not exceed 110 metres
This report on the disposal of spoil from theFor inspection LSO tunnel purposes contonly. ract was commissioned by DCC and has a Consent of copyright owner required for any other use. number of objectives in relation to the overall project:
(a) To review waste management legislation in relation to the disposal of spoil and waste classification;
(b) To describe the extent of the tunnelling exercise and the tunnelling methods; (c) To quantify and describe the spoil material that may be generated from the tunnelling operation;
(d) To identify potential disposal routes (including re-use, recycle and waste minimization); (e) To identify issues and constraints (e.g., traffic) that may be associated with various disposal route options;
(f) To provide indicative costs of various viable disposal options; (g) To recommend a route for disposal of the excavated material.
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Section 2 Waste Management Legislation
The disposal of spoil and excess material generated from excavation will be a major element of the construction phase of the Ringsend WwTW Expansion Project. The current Waste Framework Directive (2008/98/EC) was drafted to provide a policy framework for the management and disposal of waste within the European Community. This directive amended previous directives relating to waste policy and regulation. Draft regulations (Draft Waste Management (Waste Framework Directive) Regulations 2010) have been prepared for Ireland and have undergone a consultations process to incorporate into Irish Law.
The overall aims of the current Waste Framework Directive are to promote waste prevention, to increase recycling, and to ensure better use of resources, while protecting human health and the environment. It re-enacts much of the previous Waste Framework Directive, and leaves the legal definition of waste unchanged, but it also contains a number of new features.
One of the main features of the current Waste Framework Directive is that it requires Member States to apply the Waste Hierarchy as a priority in waste prevention and management legislation and policy.
2.1 Waste Classification of Spoil Waste Under the draft regulations and the Waste Framework Directive (Article 3, Section 1), waste is defined as:
“any substance or object which the holder discards or intends or is required to discard”.
However there is an exclusion from the scope of the Directive (Article 2, Section 1 (c)) for: For inspection purposes only. Consent of copyright owner required for any other use. “uncontaminated soil and other naturally occurring material excavated in the course of construction activities where it is certain that the material will be used for the purposes of construction in its natural state on the site from which it was excavated” (emphasis added)
There is limited land available as part of the proposed expansion to the Ringsend Wastewater Treatment Works Expansion Project in which to use material (in its natural state) generated from the tunnelling and excavation operations. Consequently the spoil material will have to be transported to a location off site and this exclusion does not apply.
Whilst these definitions would suggest that inert uncontaminated spoil produced from excavations in the construction phase would constitute a waste, the Waste Framework Directive states, in Section 11 of the introduction, that:
“The waste status of uncontaminated excavated soils and other naturally occurring material which are used on sites other than the one from which they were excavated should be considered in accordance with the definition of waste and the provisions on by-products or on the end of waste status under this Directive.” (emphasis added)
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By-Products Section 5 of the Regulations provides the following definition for a by-product;
“A substance or object, resulting from a production process, the primary aim of which is not the production of that item, may be regarded as not being waste but as being a by-product only if the following conditions are met:
(a) further use of the substance or object is certain, (emphasis added) (b) the substance or object can be used directly without any further processing other than normal industrial practice,
(c) the substance or object is produced as an integral part of a production process, and (d) further use is lawful, i.e. the substance or object fulfils all relevant product, environmental and health protection requirements for the specific use and will not lead to overall adverse environmental or human health impacts.” This definition would suggest that the spoil can be regarded as not being a waste provided that the criteria (a) – (d) are met (i.e. it is a waste until proved otherwise).
However, the EPA has indicated that the burden of proof is on the producer of the by-product to prove that it is not a waste and have added that there must also be a “financial advantage “. “Production residues can be elevated to by-products if it is possible to … exploit or market them on terms which are advantageous to the holder, in a subsequent process, without any further processing, and where no special precautions are necessary”. This requirement is based on ECJ's judgement - the Palin Granit Oy case (C-9/00).
When the financial advantage requirement is taken into account the spoil must still be considered as a waste rather than a by-product if no one is willing to buy it in its existing form without further processing. For inspection purposes only. Consent of copyright owner required for any other use. End-of-Waste Status Similarly Section 6 of the Regulations refers to End-of-waste status.
“Certain specified waste shall cease to be waste within the meaning of paragraph (2) of Regulation 3 when it has undergone a recovery, including recycling, operation and complies with specific criteria to be developed in accordance with the following conditions:
(a) the substance or object is commonly used for specific purposes, (b) a market or demand exists for such a substance or object, (c) the substance or object fulfils the technical requirements for the specific purposes and meets the existing legislation and standards applicable to products, and
(d) the use of the substance or object will not lead to overall adverse environmental or human health impacts. The criteria shall include limit values for pollutants where necessary and shall take into account any possible adverse environmental effects of the substance or object.”
The Directive also states:
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“For the purposes of reaching end-of-waste status, a recovery operation may be as simple as the checking of waste to verify that it fulfils the end-of-waste criteria.”
The excavated material arising from this project, if suitably processed (i.e. has undergone a ‘recovery’ operation), could have a ‘common’ use – as an aggregate in road construction or for concrete production. Alternatively, or in addition, the material could be used as an infill material in quarry restoration. This is regarded as a recycling or recovery operation within the meaning of the regulations.
It should be noted that the pre-recycled material is a waste until it has undergone the recycling recovery process which would be undertaken by a third party off site (Ringsend). The operator of such facility, i.e. where the recovery process takes place, requires an appropriate licence.
Construction and Demolition Waste Construction and Demolition (C&D) waste is defined as waste which arises from construction, renovation and demolition activities, together with all waste categories mentioned in Chapter 17 of the EWC (European Waste Catalogue) – see extract below.
17 CONSTRUCTION AND DEMOLITION WASTES (INCLUDING EXCAVATED SOIL FROM CONTAMINATED SITES) 17 05 soil (including excavated soil from contaminated sites), stones and dredging spoil. 17 05 03* soil and stones containing dangerous substances 17 05 04 soil and stones other than those mentioned in 17 05 03 17 05 05* dredging spoil containing dangerous substances 17 05 06 dredging spoil other than those mentioned 17 05 05 17 05 07* track ballast containing dangerous substances 17 05 08 track ballast other than those mentioned in 17 05 07 For inspection purposes only. * Individual sub-categories of wasteConsent may of be copyright classed owner as required hazardous for any other material. use.
The bulk of the spoil generated on the project will most likely fall under the category of 17 05 04 (uncontaminated or inert).
Summary - Waste Classification of Spoil As will be discussed later in this report the bulk of the material to be excavated in the construction of the LSO will be naturally occurring and uncontaminated (there may be a minor fraction of contaminated soil from the excavated material in the made ground at the tunnel entrance shaft, or the shallow marine sediments at the LSO exit diffuser shaft). However, as there is no potential for use of this material on site, it will be classified as a waste material in accordance with the waste management regulations.
The excavated material could reach ‘end-of-waste’ status by undergoing a ‘recovery’ operation through:
The production of an aggregate for use in road construction or concrete production; and/or
Its use as infill material for quarry restoration.
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In each case the owner/operator of the facility where the recovery operation takes place must have an appropriate licence. In addition transport of the material to the recovery facility will have to be carried out under licence as the material is waste until it undergoes a “soil recovery” process at the facility.
In cases of doubt about whether an authorisation under the Waste Management Acts is needed for a site which is proposed to accept materials that will arise and which may or may not be defined as waste, this matter can be settled by requesting the EPA for its view. This process is formalised under the Waste Management (Facility Permit and Registration) Regulations, where Article 11 entitles the EPA to make a final decision on not only on whether a waste licence, waste facility permit or registration certificate is required but also whether such an authorisation is needed at all.
Consultation with the EPA throughout the assessment of what component of the spoil constitutes waste is highly recommended.
Although a material may be defined as waste, this does not of course imply that it cannot be re-used or recycled. What it does mean is that its haulage and final processing must be fully compliant with the Waste Management Acts.
2.2 The Waste Hierarchy One of the principal features of the revised waste directive has been a requirement for member states to apply the Waste Hierarchy as a priority in waste prevention and management legislation and policy.
The following waste hierarchy shall apply as a priority order in waste prevention and management legislation and policy:
(a) Prevention;
The primary objective of the hierarchy For inspection is to reducepurposes only. the quantity of waste being produced. Consent of copyright owner required for any other use.
(b) Preparing for re-use; Further processing that is considered normal industrial practice is permitted (preparation for re-use). Checking (e.g., functionality), cleaning or repairing, recovery operations, by which products or components of products that have become waste are prepared so that they can be re-used without any other pre-processing. The assessment of suitability and selection of an end use can be regarded as preparation for re-use.
(c) Recycling ; Any recovery operation by which waste materials are reprocessed into products, materials or substances whether for the original or other purposes. This includes the reprocessing of organic material (composting) Major criterion: The material can be used again as similar material (e.g., glass, plastic, metal, paper, wood, biomass)
(d) Other recovery; e.g. energy recovery;
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Reprocessing into materials that are to be used as (secondary) fuels Backfilling operations
(e) e) Disposal; This is the least favoured option and applies to landfilling (or sea disposal) operations. Any spoil that is contaminated will have to be disposed of in a suitably licensed facility.
In the context of the spoil generated as a result of the construction activities associated with the Ringsend Treatment Works expansion project this hierarchy will be applied.
2.3 Disposal To Land On the basis that it constitutes a waste, the disposal options for the material to be removed from site will depend on whether the spoil is to be regarded as hazardous, non-hazardous or inert. The Landfill Directive (2003/33/EC) established Waste Acceptance Criteria (WAC) for different landfill types pursuant to Article 16 of and Annex II to Directive 199/31/EC and sets maximum permissible concentrations for a range of parameters. Analysis and testing of the spoil will be required to establish this. Non-hazardous and hazardous wastes are required to be disposed of to appropriately licensed landfills. Similarly, inert material can be removed for recycling, re-use or disposal to facilities licensed for the acceptance of inert waste, or to soil recovery facilities.
In the event that any component of the spoil is proven to have the required properties for a specific purpose and a ’certain’ location where it will be used (meaning it can be classified as ‘not a waste’), it will be transported to the specific sites selected.
At Sea
The Dumping at Sea Acts 1996 to 2009 prohibit For inspection the purposes dumping only. at sea from vessels, aircraft or offshore Consent of copyright owner required for any other use. installation of a substance or material unless permitted/licensed by the Environmental Protection Agency.
Schedule 2 Part 1 of the Act lists the Exceptions to the Prohibition on Dumping as contained in Annex II to the Convention for the Protection of the Marine Environment of the North-East Atlantic and includes:
“inert materials of natural origin, that is solid, chemically unprocessed geological material the chemical constituents of which are unlikely to be released into the marine environment”
Section 5.2. of the act states that: “A person who applies to the Minister for a permit under this section shall furnish to the Minister such information as the Minister may consider necessary for the purpose of the exercise of functions under this section, including, where so requested by the Minister, information that will satisfy the Minister that there is no suitable alternative means of disposal of the vessel, aircraft, offshore installation, substance or material concerned.” (emphasis added)
In order to dump material at sea a permit application must be submitted to the EPA and the application requires a considerable level of information on:
Characteristics of the substance or material
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Characteristic of the dumping site and method of deposit
Other conditions such as (a) interference with shipping, fishing, recreation, mineral extraction, desalination, fish and shellfish culture, areas of special scientific importance and other legitimate use of the sea.
(b) the practical availability of alternative land-based methods of treatment, disposal or elimination, or of treatment to render the substance or material less harmful for dumping at sea, will be taken into consideration. Certainly in the case of the outfall tunnel, a large component of spoil will probably be inert and could be suitable for use as an infill material or possibly an aggregate after suitable treatment (e.g., crushing, screening and washing).
Consultations with the EPA have indicated that the impacts on the environment of a land based solution would be taken into account in the assessment of the application. This would include the traffic impacts associated with the transporting of spoil material on trucks. If the sea disposal option were to be pursued further consultations are recommended.
In the event that an application for a dumping at sea permit is made, the EPA have indicated that it will take at least 6 months to process.
In terms of the overall impacts of the construction phase of the project there would be a significant advantage in dumping at sea as the traffic impacts associated with the transportation of spoil off site can be avoided.
In terms of the Waste Hierarchy, dumping at sea would be considered the least preferred option. (Option (e) as described in section 2.2)
2.4 Contract Provisions To ensure compliance with relevant legislation For inspection and purposes regulations, only. the Contract for the construction of Consent of copyright owner required for any other use. the LSO will include the following provisions:
All spoil and waste will be removed by waste contractors authorised under the (Waste Management (Collection Permit) Regulations, 2007 and the Waste Management Collection Permit) (Amendment) Regulations, 2008.
The waste collected will be delivered to authorised waste facilities in accordance with the Waste Management Acts 1996-2010.
The appointed Contractor will be required to produce a C&D Waste Management Plan for the project in accordance with “Best Practice Guidelines on the Preparation of Waste Management Plans for Construction and Demolition Projects”. This will provide details of the exact methods he proposes to employ to remove spoil from the site and will include details of the location and end use of the spoil.
The Contractor’s Waste Management Plan shall comply with the approved EIS for the project. The EIS will include an assessment of the disposal and transportation options and related environmental impacts.
A Project C&D Waste Manager will be appointed by the Contractor to oversee the implementation and adherence to the plan during the construction phase of the project.
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In order to ensure best value for money the Contract will allow alternatives for the disposal or re-use of the excavated material – subject to compliance with the EIS and off course relevant legislation. Section 3 Site Investigation Results and Bedrock Geology
A Marine SI for this project was carried out. The programme for Marine SI comprises:
19 boreholes in Dublin Bay (Offshore)
2 boreholes on the onshore inlet shaft location (Poolbeg Peninsula)
Offshore marine geophysics investigation (seismic reflection)
Inshore intertidal marine geophysics investigation (seismic reflection and refraction, electric resistivity)
Insitu borehole testing and laboratory sampling and testing Nineteen offshore boreholes have been completed in Dublin Bay, four of them on potential LSO discharge diffuser locations. Drilling of the two onshore boreholes is substantially complete. Geophysics investigation work is substantially completed. Laboratory sampling and testing is ongoing and will be completed by August 2011 approx. The locations of the 19 marine boreholes are shown on Figure 2.
For inspection purposes only. Consent of copyright owner required for any other use.
Figure 2. Marine borehole locations The geology in the marine bay area consists roughly of marine sediments which are followed by underlying glacial till. The glacial till comprises layers of marine deposits as well. These sediments/tills are underlain mainly by Calp limestone. However, in some boreholes (for example BH M 20, M 21), glacial till was not encountered. Equally in some other boreholes, such as M 21, Calp limestone was not encountered. In M21 the underlying bedrock is actually Waulsortian limestone.
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The sediments comprised a mixture of grey coloured silty - gravelly sands, silty – sandy clays and fine- coarse gravels with very occasional cobbles of a grey argillaceous limestone and occasional quartzite. Cobbles if present ranged from 40mm to 130mm in size. Gravels were described as being sub- angular to sub-rounded in shape and were composed of grey limestone. Sand is described as fine or medium in most of the samples. Layers of sandy gravel were also described as containing occasional pockets (<60mm) of a dark grey silty clay. Marine sediments sampled in Borehole M10 consisted of silt or sand and were described as having a slightly organic odour. Shell fragments (5-10mm) were present in the sand layers on occasion and identified as bivalve shells, or in some cases as razor shells.
The glacial till comprises layers of sands, clay, gravels, cobbles and boulders. Glacial till is usually described as a grey slightly clayey sandy gravel with occasional cobbles and boulders of limestone. Gravel is usually angular to rounded in shape, and can be fine to coarse and usually of a light grey coloured limestone. Cobbles found in the till are described as being sub-angular in shape and are of medium strong or strong dark grey argillaceous limestone. These boulders in general were described as a dark grey argillaceous limestone with calcite veining (<20mm) present and in some cases contained rare pyrite crystals (<5mm). The occasional cobble of green quartzite is also described. The glacial boulder clay is usually described as firm grey coloured gravelly sandy clay (occasionally soft) with occasional to many cobbles and boulders of limestone. Boulders described in M11 are large (300mm x full drilled core circumference) and are of strong dark grey argillaceous limestone. The extent of the glacial till/boulder clay found in the marine boreholes of Dublin Bay range between ca. 4 and 47 m.
The bedrock surface is very uneven and was found between ca. -14 m and – 55 m below seabed level which is ca. -18 and -65 m to OD Malin Head. The bedrock consists for the most part across the project area of Calp limestone. In the area at Burford Bank, limestone of the so-called Bray-Group was encountered. In one borehole (BH M 21), Waulsortian limestone was encountered
The top of the Calp limestone was generally quite fractured and often recovered as fragmented non- intact moderately weathered limestone. For inspection The purposesdeeper only. limestone is mostly unweathered and Consent of copyright owner required for any other use. competent. However, fractured zones occur in the deeper sections as well. The Calp limestone consists in particular of layers of limestone as well as of layers of claystone. The Calp limestone is a medium strong dark grey coloured argillaceous limestone. It displays calcite veining in many locations and this veining is sometimes described as closely spaced subvertical veining. These veins can range in size between <0.5mm to < 5mm. Some fractures in the limestone are reported as infilled locally with either clay or sand layers (usually < 1.5 m). Crinoid stems and shell fragments are frequently found in the bedrock, usually measuring < 4mm diameter. Pyrite crystals were also present in small amounts in the limestone, and are described as rare to frequent in some cores. The pyrite crystals were usually < 2mm in size. Fractures in the Calp limestone can range from locally very closely spaced to medium spaced, and can be described as rough to smooth, and are generally inclined.
The limestone of the Bray group was found mostly heavily weathered down to soft soil. The transition zone between these two types of limestone – Bray and Calp - was not encountered, but it is likely that a major fault determines the border between those two rock types. To date no fault locations have been identified from any of the Marine SI work. An indicative - typical cross section showing the inferred geology (based on Marine SI information available to date) between the proposed onshore tunnel inlet shaft site and the LSO offshore exit diffuser shaft near to preferred discharge location B3 is shown in Figure 3.
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Figure 3: Typical cross section - Inferred geology The overall geology of the area will be presented in a document on Dublin Bay Geology at a later stage when the Marine SI has been completed and all results analysed.
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Section 4 Potential Construction Methods.
As noted in the introduction, it has been assumed when preparing this report that the LSO tunnel will be constructed in bedrock. The LSO tunnel inlet access shaft will be constructed through a combination of made ground in the Poolbeg Peninsula and unconsolidated soils overlying the underlying bedrock and so both soft and hard ground construction methods will have to be employed.
4.1 Onshore Tunnel Access Shaft For the purposes of this report it is assumed the onshore tunnel access shaft through the soils above the underlying bedrock will probably be excavated inside a ring formed of interlocking straight diaphragm wall panels, of the order of 1 m wide, that will be excavated with grabs through unconsolidated strata and with rock cutters or a hydrofraise machine to key into the underlying rockhead. The wall panels will be supported using bentonite slurry during the excavation process. The structural walls are formed by inserting steel reinforcement panels into the slurry that is then displaced (and collected for re-use) from the bottom of the excavation upwards with tremied concrete. The soil within the perimeter of these walls is then excavated using conventional excavators and skips in the shaft bottom.
It is anticipated that the overburden soil strata to be excavated will comprise made ground (domestic and building waste), sand, gravel and glacial clay/till. This will be confirmed by the drilling of onshore site investigation boreholes. Soils excavated from the diaphragm wall panels will be cleaned of the bentonite before onward disposal off site: the cleaned bentonite slurry will be removed from site for re-use or disposal by the tunnel contractor. Soils excavated from within the area enclosed by the diaphragm walls - down to bedrock - are unlikely to require pre-treatment before disposal at appropriate off-site locations.
Shaft excavation in the bedrock below the For inspection overburden purposes only.will probably be by means of drill and blast Consent of copyright owner required for any other use. with fragmented rock being loaded into skips for transport to the surface. It is unlikely that this rock will receive any chemical treatment during the excavation process – therefore no pre treatment is envisaged before removal from site for onward disposal to an off site location.
4.2 Tunnelled Section A review of the excavation methods available for construction of the LSO tunnel in rock concluded that the tunnel will most likely be constructed using a tunnel boring machine (TBM).
A full-face TBM produces a circular tunnel profile with a minimum of overbreak and disturbance of the surrounding rock mass. Although there will not be any difference in the grading of the spoil arising from excavation using shielded and unshielded full-face TBMs, it is considered that a shielded TBM will provide a safer working environment for the workforce, with less risk of major problems arising due, for example, to broken rock or water inflows than would a more open main beam or gripper TBM. The additional safety arises because, in a shielded TBM, the tunnel lining is constructed in the tailskin of the TBM using precast concrete segmental rings. The annular void between the lining and the surrounding rock when the shield advances is filled immediately with grout injected from within the tailskin. Whether a single shield or double shield TBM is employed will be governed by the Contractor’s preference.
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Types of TBM which could be used are a conventional full-face rock TBM, an Earth Pressure Balance Machine (EPBM), or a slurry TBM (STBM).
The spoil produced by all three types of TBM will have similar gradings since the cutter heads would have similar configurations of disc cutters. The potential differences between the spoil produced by each type of TBM are:
The full-face rock TBM produces spoil that can vary from very wet to damp (due to dust suppression sprays at the face) and, most probably, it will be transported to the surface using belt conveyors. Provided that it is not considered to be excessively wet, it can be disposed off straight from site without further pre-treatment.
When the EPBM is used without any soil conditioners, the spoil will be the same as that produced by the full-face rock TBM and will be transported to the surface in the same way. If it is considered necessary to introduce (usually biodegradable) conditioners in order to provide additional support to the tunnel face, the nature of these will have to be ascertained to determine if pre treatment will be required and the necessary appropriate action taken before disposal of the spoil to an off site location.
Spoil is pumped in a liquid slurry form to the surface from a STBM – usually with water added as the liquid phase for the slurry. If it is not necessary to provide support to the tunnel face, the only other constituent of the slurry will be the excavated spoil: this will probably require some draining/drying before it can be removed from site. If additional additives, such as bentonite, are required to provide support to the tunnel face or for other reasons, it will be necessary to remove the bentonite from the slurry using standard plant located topside of the shaft before the cleaned tunnel spoil can be disposed to an off site location. 4.3 Tunnel Outlet Diffuser Shaft Currently it is assumed that the offshore tunnel outlet diffuser shaft will be constructed from a deepwater marine barge/drilling ship using purpose designed and preformed steel shaft caissons. For inspection purposes only. These caissons are expected to be Consentinstalled of copyright during owner two required construction for any other use. phases;
• Phase I: Involving the sinking of an outer larger diameter caisson through the softer overburden sediments/glacial tills down to the bedrock interface.
• Phase 2: Involving the sinking of an inner smaller diameter caisson through the underlying bedrock down to the tunnel crown.
For Phase I construction it is expected that inner material within the caisson will be excavated with a larger diameter borehole drilling rig through unconsolidated strata and into the underlying rockhead. Soils excavated from within this upper area may need pre-treatment before disposal to an off site location – particularly if bentonite slurry has to be used in support of the drilling operation.
For Phase 2 construction it is expected that inner material within the caisson will be excavated with a larger diameter borehole drilling rig through the underlying bedrock. Soils excavated from within this upper area may need pre treatment before disposal to an off site location – particularly if bentonite slurry has to be used in support of the drilling operation.
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Section 5 Spoil Composition
Excavated spoil material will fall into two main categories:
Underlying solid bedrock material (Type A) located below weathered bedrock material, boulder clays, marine sediments, made ground, etc.
Overburden weathered bedrock material (Type B), glacial tills/clays, marine sediments, made ground, etc. located above the underlying bedrock. The site of the proposed onshore tunnel inlet shaft on the ESB lands in the Poolbeg Peninsula is on reclaimed ground and there is a possibility that infill material may be contaminated. Site investigation boreholes are currently being undertaken to establish the ground conditions and the extent of contaminated material (if any).
Initial indications are that the underlying bedrock material at this location may not be Calp limestone or of a common consistency as it may contain layers of mudstones/silts, etc.
The spoil will be further differentiated in terms of whether it is considered to be:
Waste
o Hazardous o Non-Hazardous o Inert Non-Waste - Suitable for Re-use This differentiation of the waste material will be achieved by analytical testing of the spoil. Hazardous and non-hazardous spoil will require disposal in suitably licensed landfill facilities (i.e. where the spoil meets the waste acceptance criteria for a particular facility). In the case of spoil that For inspection purposes only. is classified as hazardous (containingConsent “dangerousof copyright owner substances”)required for any other theuse. waste will be required to be exported to mainland Europe for treatment and disposal, as there are presently no suitable licensed facilities available in Ireland.
At this stage, however, there is insufficient information to definitively classify the bedrock material and its chemical composition along the proposed route of the tunnel, or in the tunnel onshore inlet and offshore diffuser shafts. Such information will only become available following completion of the Marine SI. This may ultimately impose limitations on the disposal options.
The spoil composition will also be dependent on the preferred shaft construction and tunnelling techniques. For the purposes of this report it is assumed that most of the spoil from the tunnelling operation will be inert Type A material.
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Section 6 Spoil Quantities
For the purposes of this report the following working assumptions have been made:
The onshore tunnel inlet shaft internal finished diameter is 15 metres – with 1.5 metre wall thickness. The external excavated shaft (allowing for overdig) diameter is expected to be 20.0 metres. The onshore tunnel inlet shaft depth will be 110.0 metres below existing ground level.
The tunnelled section internal finished diameter is 5.0 metres. Because of expected overdig issues the tunnelled section external diameter is expected to be 6.5 metres. These are conservative assumptions resulting in the greatest amount of spoil generated per unit of tunnelled section length. The tunnel section length is 9.0 km.
Whilst a final decision has yet to be made on the number of diffuser shaft/s required at the offshore tunnel outlet discharge diffuser shaft location the cumulative cross sectional areas of the excavated diffuser shaft/s will be equivalent to a single shaft with an external diameter not exceeding 6.0 metres. Diffuser shaft/s will be comprised of 25.0 metres depth approx in Dublin Bay overburden sediments and 85.0 metres depth approx in underlying bedrock. Table 1 details the quantities of spoil associated with this assumed outfall construction.
Table 1: Estimated tunnel excavated material quantities
Bulked Type A Type B Volume Assumed Assumed Assumed In- Overburden, length/ external (applying Situ Volume (Solid Made Ground, depth diameter bulking Bedrock) Weathered factor of 1.7) Bedrock m m Cubic metres Cubic metres (tonnes) (tonnes) Onshore tunnel inlet shaft – Overburden 30 20 For inspection9,425 purposes only. 16,023 14,138 sediments and made Consent of copyright owner required for any other use. ground Onshore tunnel inlet shaft – Underlying 80 20 25,133 42,726 62,833 bedrock Tunnelled Section - 9,000 6.5 298,648 507,702 746,620 Bedrock Offshore discharge diffuser shaft – 25 6 707 1,202 1,061 Overburden sediments and made ground Offshore discharge diffuser shaft Underlying 85 6 2,403 4,085 6,008 bedrock Total Quantities (Volume) 336,316 571,737 Total Weight : Metric Tonnes Rock - Assumed 2.5 metric tonnes/m3 815,461 15,199 Overburden - Assumed 1.5 metric tonnes/m3 Note: Additional spoil ( 20,400 m3 approx)will be generated from the excavation of 6 deep aeration shafts (depths of 120 metres) on the existing Ringsend wastewater treatment site. However, as these works will be undertaken under a different Contract, the associated spoil disposal issues are not incorporated within this report.
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It should be noted that excavation increases the volume of material. The volume of 1 m3 of solid bedrock will increase once it has been broken up for excavation. Table 1 shows the volume of material that is removed to create the tunnel (in situ volume) and then a bulking factor of 1.7 is applied in order to estimate the spoil volume for transportation purposes. It should be noted that the bulking factor for the overburden material would be somewhat lower. However, a factor of 1.7 has been universally applied to ensure a conservative estimate.
The mass of the excavated bedrock is calculated on the basis of the limestone having a mass density of 2.5 tonnes/cubic metre.
It is clear from Table 1 that bedrock will be by far the greatest proportion of the spoil generated (98%). This estimate will be refined once data from the Marine SI becomes available.
A total of 830,660 tonnes (571,737 m3 bulked volume) of spoil is estimated to be generated as a result of the excavation and tunnelling operations, as summarised below:
Table 2: Estimated spoil quantities summary
Volumes In situ 336,316 m3 Bulked 571,737 m3 Weight Type A 815,461 metric tonnes Type B 15,199 metric tonnes Total 830,660 metric tonnes
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Section 7 Disposal Options
An assessment of the possible destinations for spoil material has been undertaken. Preliminary consultations and discussions have taken place with relevant agencies and facility operators.
Railway Procurement Agency (RPA)
Roadstone Ireland
Murphy Environmental (waste facility operator)
John Behan (waste facility operator)
EPA
NRA
Fingal County Council The potential destinations will be determined by;
The composition of the material
The waste classification of the material
The Waste Hierarchy
The demand for the material
The costs of removal
The impacts associated with the removal. 7.1 Potential Uses The downturn in activity within the construction industry will have a limiting effect on the number of For inspection purposes only. potential outlets for the spoil generated.Consent of copyrightThe demand owner required for for infill any other material use. for engineering projects was limited in the past and is now almost non-existent. Discussions with operators indicate that at present there is little or no demand for this type of material for major engineering projects. The only possibility may be port developments. There is, however, a requirement for infill to licensed infill projects, or quarry restoration, etc.
7.1.1 Infill Material for Engineering Projects The ideal solution would be as fill material that is required for some construction project in the vicinity. Harbour and Port Development would be the preferred option as the spoil would be transported by sea and avoid traffic impacts. If any of these project were to go ahead and it could be agreed to provide the spoil for the reclamation phase the need to identify a specific end use for the material would be fulfilled.
Dublin Port Dublin Port had intended to infill a 52 hectare area in a land reclamation project as part of its Dublin Gateway proposal. Planning permission for this project was refused on environmental grounds and the company is considering the implications of this decision. Given the uncertainty regarding the land reclamation projection proceeding and the length of time that would be required for the
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EPA Export 10-12-2012:23:36:45 Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study associated planning process this is not considered a viable option for disposal of the excavated material from the tunnel project.
Bremore Port A major deep water port facility is proposed in Bremore near Balbriggan. There may be a requirement for considerable volumes of inert infill material for this development. The information available suggests that the facility will not be applying for planning approval before 2015. This would not fit with the time scale for the construction of the tunnel whereby tunnelling operations are expected to commence during 2013.
Rosslare Harbour Development There are proposals to expand Rosslare Port. Preliminary conversations with Port Authority personnel have indicated that there is a shortage of land available and that the preferred solution is reclamation. They have confirmed their interest in the spoil from the Ringsend project as infill material. However, this project has yet to be submitted for planning approval and it is believed that it would have to be fast tracked in order to have all the approvals and permissions in place by the early 2013.
Other Construction Projects Enquiries with Fingal County Council personnel indicate that there are no significant engineering projects with a use for spoil material.
NRA Road Projects NRA project personnel were consulted regarding any future major road projects in the Leinster area that could utilize spoil material as road sub-base. No projects were identified and it was pointed out that projects were designed on a cut and fill basis and in order to minimise the need for imported materials.
For inspection purposes only. Consent of copyright owner required for any other use. 7.1.2 Recycle to Produce Aggregate The spoil generated from the rock tunnelling operation (i.e. Type A material) has the potential to be recycled into aggregate. The aggregate could be used as a component of the concrete to be used on site. However the spoil will require crushing and screening. There will also be a component that will need to be removed. Because of space limitations at the proposed tunnel construction compound at the ESB site it would not be feasible to establish crushing, separation and storage facilities there and therefore if the spoil is to be recovered as an aggregate, the spoil will be transported to a licensed C&D waste facility/ soil recovery facility where recycling can be undertaken. The potential suitability for recycling of the spoil as aggregate would be the decision and risk of the licensed facility operator.
A meeting was held with Roadstone personnel and they informed us that spoil from the Port Tunnel was sent to the Huntstown Quarry (license now lapsed but it has been resubmitted). The value for recycling is very dependent on the size of the material delivered and the amount of dust present. The spoil from the Port Tunnel had a high dust content and this made it almost useless for anything except infill. There is still a large amount of this material stockpiled on site. If the Ringsend tunnel spoil is of a similar size and quality, then the only use Roadstone can see is as infill in quarry restoration (soil recovery).
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There would be no financial benefit to the suppliers (tunnelling contractor/DCC) of the spoil in the event that it is recycled (by a waste facility) as aggregate for the construction industry. The downturn in the construction sector has resulted in a steep drop in demand for aggregate and construction materials.
Consequently it is considered that recycling for re-use as an aggregate is highly unlikely.
7.1.3 EPA Licensed Facilities, Quarry Restoration (Soil Recovery Facilities) Waste facilities that could be considered as a destination for the tunnel spoil are listed below. These are facilities licensed for soil recovery (quarry restoration) and C&D licensed landfills. Large inert waste facilities accepting natural soils and sub-soils for deposition on land now require a waste licence from the EPA. This type of waste activity may have previously operated under a waste facility permit issued by the relevant Local Authority.
Operational Licenses
• (W0247-01) Behans Land Restoration Ltd. Waste Licence granted for a natural soils recovery facility. This waste licence relates to the restoration of a former sand and gravel quarry using imported inert soils and stones, and recycling of inert construction and demolition waste, at Blackhall Soil Recovery Facility, Blackhall, Punchestown, Naas, County Kildare. The amount of inert material to be imported and placed at the facility over a 15-year period is approximately 4 million tonnes (approximately 2.24 million cubic metres) with a maximum limit of 344,000 tonnes per annum. This facility is classed as a natural soils recovery facility, with the principal activity identified as Class 4 of the Fourth Schedule to the Waste Management Acts 1996 to 2008; recycling or reclamation of inorganic materials.
Inert construction and demolition waste is also recycled at the facility using crushing and screening equipment to generate recycled aggregates. These aggregates will be used for the construction of temporary haul roads and infilling of groundwater ponds at the facility, with any excess aggregates For inspection purposes only. exported off-site for sale as hardcoreConsent in ofconstruction copyright owner required works. for any This other facilityuse. is located approximately 50 kilometres from the Poolbeg Peninsula (via Port Tunnel).
2. W0151-01 Murphy Environmental Limited
Soils Recovery Facility at Sarsfieldtown, Gormanstown, Co. Meath. The license is for operation of an inert landfill in a sand and gravel quarry and is approximately 33 ha in size. The licence allows for recovery, either for use at the landfill itself or for use as aggregate material and disposal of inert waste to landfill. A maximum tonnage of 750,000 tonnes per annum can be accepted to the facility. This facility is located immediately adjacent to the M1 and is approximately 40 km from the Poolbeg Peninsula (via Port Tunnel).
3. W0269–01 Roadstone Wood Ltd
Waste licence for a soils recovery facility at Fassaroe, Bray for recovery of a maximum of 550,000 tonnes per annum of soils, subsoil, stones, rock and construction and demolition waste. The facility has been granted planning permission for construction and demolition waste recycling at the site and for backfilling and restoration of an existing quarry. This facility is located approximately 50 kilometres from Poolbeg Peninsula (via Port Tunnel)
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4. (W0129-02) Murphy Environmental Hollywood Limited
Waste Licence, for a landfill restoration of a former quarry approximately 39.2 hectares in size. This facility is licensed to intake a maximum of 500,000 tonnes of waste per annum. This site is located approximately 30 kilometres north of Poolbeg Peninsula off the M1 (via Port Tunnel).
5. Other licensed landfills (primarily for dumping with limited recovery) are Balleally operated by Fingal County Council (W0009-03) and Greenstars Knockharley landfill (W0146-01). Their licences also permit the acceptance of limited but small quantities of C&D waste. Because of their small operational capacity these two sites have not been considered any further within this report.
Current Licence Applications with EPA for Assessment.
1. W0272-01 Roadstone Wood Ltd
Applied for a waste licence in October 2009 for Milverton Waste Recovery Facility at Milverton, Skerries, County Dublin for recovery of a maximum of 400,000 tonnes per annum of soils, subsoil, stones, rock and construction and demolition waste. The facility has been granted planning permission for restoration of an existing quarry. This site is located approximately 32 kilometres from Poolbeg Peninsula (via Port Tunnel).
2. W0277-01 Roadstone Wood Ltd
Roadstone had held a licence for the Huntstown Quarry. This has now lapsed but Roadstone have applied again for a licence as a soil recovery facility. This facility took in spoil from the Dubin Port Tunnel. They also believe that the renewal of the licence would be relatively straight forward. If licensed they could accept whatever quantity is produced from the tunnel outfall construction (for a gate fee). It is immediately adjacent to the M50. This site is located approximately 20 kilometres from Poolbeg Peninsula (via Port Tunnel).
3. W0264-01 Sand and Gravel Merchants For inspection Ltd. purposes only. Consent of copyright owner required for any other use.
Application to EPA for a licence for the continued phased restoration of a sand and gravel pit (Thornberry, Kill, County Kildare) using imported inert soils, stone, and recovery of inert construction and demolition waste. It is proposed that up to 220,000 cubic metres per annum of inert materials will be accepted to site. The site presently has a waste management permit WMP 30/2001B. This site is located approximately 50 kilometres from Poolbeg Peninsula (via Port Tunnel).
4. Roadstone Arklow.
There is no licence for this quarry nor have Roadstone applied. However, this site would have considerable benefits in the context of the tunnel project, primarily due to the fact that the quarry is located on the coast and has its own Jetty. The spoil from Ringsend could be transported by sea to the site. This would greatly reduce the traffic impacts associated with transport overland by truck. However, Roadstone have indicated that apart from the Ringsend spoil there are few other sources of material for this project and therefore they would consider that there is a risk in going through the application process with its associated costs as there is no guarantee that the successful contractor would actually use the facility.
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W 0151-01
W 0272-01 W0129-02
W 0277-01
Tunnel Location
W 0264-01 W 0269-01
Operational License W 0247-01 Current LicenseW A 0pplication048-01 Tunnel Shaft Location
For inspection purposes only. Figure 3: Waste Facilities (OperationalConsent l oficen copyrightses ownerand requiredactive for licen any otherse ause.pplications)
The capacities of the above soil waste licensed facilities are summarised in the following tables:
Table 3: Licensed waste facilities
Facility Capacity Behans 344,000 tonnes/year Murphy Env 750,000 tonnes/year Roadstone Fassaroe 550,000 tonnes/year Murphy Hollywood 500,000 tonnes/year Total 2,144,000 tonnes/year
Licence Pending Facility Capacity Roadstone Milverton 400,000 tonnes/year Roadstone Huntsown 750,000 tonnes/year Kill 220,000 m3
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Based on the above it is considered that there are a sufficient number of suitable land based licensed facilities available in the region which will be available to take the spoil material from the LSO tunnel construction.
7.1.4 Disposal at Sea In view of the total volume of material to be disposed; having regard to the associated potentially significant traffic impacts and costs of using land based outlets and because there is an existing designated marine spoil disposal area adjacent to Burford Bank - which is used for depositing dredged material from Dublin Port and environs - consideration is given to disposing of the excavated tunnel material at sea.
Although this area is used as a spoil disposal ground by others, a separate permit would be required if it is intended to make use of this area as part of this tunnel project. The application would be made to the EPA. They have indicated informally that the review of the permit application will take at least 6 months. This permit would have to be in place prior to the commencement of the tunnelling operation. Consequently Dublin City Council would be the applicant.
Initial conversations with the EPA have indicated that the onus would be on the applicant to show that there are no practical land based alternatives. As discussed above it would appear that there are such alternatives available. However, the EPA have also indicated that they would be pragmatic and would be willing to take into account issues such as costs and environmental impacts associated with land based spoil disposal as part of any overall assessment for a marine disposal permit for the designated spoil disposal area at Burford Bank.
7.1.5 Disposal to Landfill (Non-Hazardous) It is likely that relatively small quantities of the spoil will contain contaminants (a fraction of the excavated overburden which constitutes 2% of the total excavated spoil). This material will be analysed for compliance with the waste acceptance criteria for suitably licensed landfills. If the spoil For inspection purposes only. falls within the non-hazardous categoryConsent of (meets copyright ownerthe wasterequired for acceptance any other use. criteria) it can be disposed off in Ireland at a suitably licensed facility.
7.1.6 Export (Hazardous) If a portion of the spoil generated is contaminated and fails to meet the waste acceptance criteria for non hazardous disposal in Ireland it will have to be exported for disposal to mainland Europe as there are no hazardous waste facilities in this country.
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Section 8 Spoil Disposal Transport Options
The excavated material will be temporarily stockpiled on site for several days only. There are two potential transport options for disposal;
Removal by truck
Removal by sea 8.1 Land based disposal - Removal by truck Land based disposal will involve all trucks leaving the Poolbeg Peninsula area via the Ringsend roundabout.
Preliminary discussions have been held with DCC Traffic Department. They have indicated that:
• Removal by truck will have to take account of the Dublin City axle ban even though the tunnel construction compound site is located outside the axle ban perimeter.
• If removal by truck is undertaken then all traffic will have to access and leave the Poolbeg Peninsula via the East Link Toll and the Port Tunnel.
• No truck movements will be permitted during peak traffic times. The peak time restriction will probably not apply on Saturdays.
• Truck movements at night are unlikely to be permitted due to potential disturbance to local residents in Ringsend.
• Spoil removal by road will be permitted on week days (Monday – Friday) between 10:00 and 16:00 and 19:00 and 22:00 and half day on Saturday between 9:00 and 13:00. This amounts to a maximum of 9 hours per day. For inspection The principal purposes only. impacts will be between the construction Consent of copyright owner required for any other use. compound site and the Port Tunnel. Once the trucks have entered the Port tunnel little significant traffic impacts are predicted.
For the purposes of this study only rigid body tippers are considered. The successful contractor may decide to use articulated trucks with a greater capacity. However, there is limited availability and they are less manoeuvrable in rough ground. It is considered that the rigid trucks represent the most likely option as well as the worst case scenario in terms of traffic volumes.
• Rigid Body Tipper – 8.0 cubic metres
From Table 1 it has been established that the estimated volume of excavated material associated with the tunnelling will be 571,737 m3 (bulked volume). Using the above lorry capacities this translates into the following truck movements:
• Rigid Body Tipper – 71,467 trips – each direction
The rate of tunnelling progress will vary. For the purposes of this report the daily volumes of spoil generated are assumed to be of the order of:
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• Average tunnelling rate (16.5 m/day) 931 m3 per day of bulk spoil
• Peak tunnelling rate (30 m/day) 1,693 m3 per day of bulk spoil
This would indicate that the number of truck trips per day, each direction, required to remove the spoil will be:
• Average 116 trucks per day – i.e. 232 truck movements (Outward/Inward) per day
• Maximum 212 trucks per day – i.e. 424 truck movements (Outward/Inward) per day
If the daily permissible working hours from above of 9 hrs maximum are considered these truck movements for spoil disposal only (there will also be other very significant construction related vehicular traffic for staff, materials delivery, and the RIngsend WwTW upgrade contract which will be running concurrently) translate into the following;
Table 4: Estimated truck movements at Ringsend roundabout for land based spoil disposal
Tunnel Drive Number of trucks Number of trucks per Approximate number of trucks in Production (8.0 m rigid body) hour based upon 9 minutes based upon 9 hrs/day Rate Inward/Outward hrs/day Average 232 26 1 truck every two minutes Maximum 424 47 4 trucks every five minutes
8.2 Sea based disposal - Removal by boat/barge If removal by sea proves to be a viable option then the material can be loaded onto barges at a suitable jetty in the Poolbeg Peninsula . There are currently two sea disposal destination options that have been considered. The types, number of barges, ships required will depend on the final disposal destination. Transport by sea has the advantage that significant traffic impacts could be For inspection purposes only. localised and managed within the ConsentPoolbeg of copyright Peninsula owner required area for inany theother use.vicinity of the tunnel construction compound therefore minimising impacts outside of the Poolbeg Peninsula area.
Transport by Sea for Use in Rosslare Port Expansion. In the unlikely event that the development of Rosslare Port proceeds and that it has the necessary permissions transfer of material would be by sea. In this scenario the unloading of the spoil would require specialised equipment to enable the deposition at specific locations both on land and in the water. Also the travel time involved (approximately 16 hours each way) would necessitate the provision of two vessels to transport the spoil. Consultations with an international dredging company have suggested that two flat top barges (capacities in the order of 2,500 m3 each) and a sea going tug as well as a delivery system to transfer spoil to specific locations would be required. This equipment (typical sample shown below) would need to be available for the duration of the spoil generation phase (30 months approx) of the tunnel project.
Transport by Sea to Burford Bank. The disposal of spoil at the existing spoil disposal area to the immediate West of Burford Bank (on receipt of Dumping at Sea Permit from EPA) is more straightforward operation that can be accomplished by a single self propelled split barge (typical sample shown below). The return trip to
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EPA Export 10-12-2012:23:36:45 Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study the Burford Bank will take approximately 1 - 2 hours each way plus an allowance of 1 – 2 hours for precision dumping. The barges themselves will also provide storage capacity for the spoil in times of poor weather when marine spoil disposal operations cannot proceed. This equipment would need to be available for the duration of the spoil generation phase (30 months approx) of the tunnel project.
Figure 4: Self Propelled Split Bottomed Barge.
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Section 9 Costs
The cost of disposal is taken to be the sum of the transport costs, including toll costs and the gate fee costs. The costs provided below should be taken as indicative only at this stage. They represent the relative costs of the various options.
9.1 Haulage Costs by Road to Licensed Facility An estimate of the costs of transporting spoil away from the site has been made based on the hire of rigid tipper trucks and drivers. The estimate of the haulage costs are shown in the table below. It is assumed that rigid body tipper trucks with a capacity of 8 m3 will be used. All trucks will have to pass through the East Link Toll and the Port Tunnel.
Table 4: Haulage Costs
Total Spoil Volume (m3) 571,737 Truck Capacity (m3) 8 Total Truck Return Trips 71,467 Daily Bulked Spoil Volumes (based on 16.5 metre day long average) (m3) 931 Average Trucks/ Day 116 No. of Return Trips/Truck/day (Based upon destination within 40 km) 4 Volume Transported/Truck/Day 32 Total Truck Days to Remove Tunnel Spoil 17,867 Cost of Truck/day €470 East Link Toll costs per return trip €12 Total East Link Toll Costs €857,604 Total Haulage Costs €9,255,094 Haulage Cost per m3 €16.19
For inspection purposes only. Consent of copyright owner required for any other use.
The cost of rigid tipper truck plus driver is €45/hour. Truck cost is €470/day. It is assumed that 1 cubic metre of spoil weighs 1.5 tonnes. Each truck is assumed to make 4 return trips per day. It is also assumed that there are no toll charges for the use of the Port Tunnel. However, there will be a toll charge of €6.0 for each crossing of the East Link Bridge (i.e. €12.0 per return trip)
Based on the above assumptions the transport cost of land based spoil disposal will be €16.19 per m3.
9.2 Gate Charges Licensed Facility Enquiries were made to various licensed facilities regarding the gate charges. Indicative estimates were provided based on the material being inert and/or meeting waste acceptance criteria. Costs are based on the gate charge per load.
The indicative gate fees for a soil recovery facility vary from €25 - €40 - €120 per 8 cubic metre load (€3.13 - €5.00 – €15 per m3) depending on which facility is selected.
Soil recovery facilities which are licensed to accept only inert waste to be used as fill material will be cheaper than lined landfill sites.
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9.3 Overall Cost - Transport and Disposal to Licensed Soil Recovery Facility Based on the above the estimated costs of disposal to a land based soil recovery facility are of the order of €19.30 to €31.20 per m3 (haulage + gate fee) The total estimated cost is therefore in the range of €11 million and €17.8 million approx.
It should be noted that the transport/haulage component constitutes between 52% and 84% of the overall costs.
9.4 Transport by Sea (Dumping at Sea or Rosslare Port Reclamation) As outlined in Section 8.2 the options of transporting by sea to either, a land reclamation project such as the expansion of Rosslare Port, or dumping at sea at the designated spoil grounds west of the Burford Bank were considered.
The period of tunnel and inlet shaft spoil generation is estimated to be in the order of 30 months. Discussions with an international dredging company suggested indicative requirements and rates. If transport by sea to a land reclamation project such as Rosslare is the preferred option they indicated that spoil management could be accomplished using two large flat top barges and a sea going tug to tow the barges to the selected disposal point. However, if the spoil were to be dumped at the designated spoil grounds west of the Burford Banks, a single self propelled split bottom barge would be sufficient.
The indicative cost estimates for the Rosslare and Burford Bank options are detailed below.
Table 5: Dumping at designated spoil grounds to West of Burford Bank (+ Table 7 costs)
For inspection purposes only. Total Spoil Volume (m3) Consent of copyright571,737 owner required for any other use.
Barge Capacity (m3) 1,000 Self Propelled Split Barge Hire Cost per day (inc Crew) €7,500 Will be Based on 7 Day Week Hire Duration (days) 913 30 Months (7days/Week ) to include shaft excavation Total Hire Cost €6,847,500 Permit Application Drafting and Supporting Data €150,000 Total Costs €6,997,500
Table 6 : Providing Fill to Rosslare Port Expansion (+ Table 7 costs)
Total Spoil Volume (m3) 571,737 2 x 2500 m3 Capacity Flat Top Barges Plus 1 No. Sea going Tug Including specialist unloading plant for deposition at Rosslare Hire Cost per day (inc Crew) €20,000 Will be Based on 7 Day Week Hire Duration (days) 913 30 Months (7days/Week )to include shaft excavation Total Cost €18,260,000
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Table 7 : Local road haulage costs to deliver spoil to Ringsend jetty – all sea disposal options
Total Spoil Volume (m3) 571,737 Truck Capacity (m3) 8 Total Truck Return Trips 71,467 Daily Bulked Spoil Volumes (based on 16.5 metre day long average) (m3) 931 Average Trucks/ Day 116 No. of Return Trips/Truck/day (Based upon destination within 1 km) 10 Volume Transported/Truck/Day 80 Total Truck Days to Remove Tunnel Spoil 7,146 Cost of Truck/day €470 East Link Toll costs per return trip - Total East Link Toll Costs - Total Haulage Costs €3,358,620 Haulage Cost per m3 €5.87
9.5 Hazardous Waste for Export to Continent The proposed onshore tunnel inlet shaft entrance (and the Ringsend WwTW plant) is located on the Poolbeg Peninsula which is partially reclaimed land. Consequently there is a possibility that contaminated soil will be excavated. If this falls within the hazardous category of waste the material will have to be exported to mainland Europe because there are no waste facilities in Ireland licensed to accept hazardous waste. The cost of disposal is dependent on the degree and type of contamination.
A conservative estimate of the cost of export (including transport by ship) would be in the order of €150 per tonne. This would be lower if the only contamination was hydrocarbons. It should be noted that this indicative cost would be based on the contaminated soil being removed in one trip.
For inspection purposes only. The results of the Marine SI soil analysesConsent of copyright will p rovideowner required an forindication any other use. of the quantity that would need to be exported.
Only the soil that is contaminated above Irish Waste acceptance levels would need to be exported. It is expected that the soil excavated from depth or below boulder clay horizons would not be contaminated. Contaminated spoil is expected not to be a big issue for the tunnel project as any excavated volumes are likely to be small.
9.6 Summary of Spoil Disposal Cost Estimates Based on a total volume of 571,737 m3 the estimated costs of transport and disposal of excavated material (excluding any hazardous material) are summarised as follows:
Land based disposal €11.0 million to €17.8 million
At Sea – Burford Bank €10.4 million
At Sea – Rosslare Port €21.6 million
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Section 10 Summary and Recommendations
10.1 Summary of Main Findings The main findings of this study are as follows:
It is proposed to construct a LSO tunnel as part of the overall Ringsend WwTW Extension Project planned for the Poolbeg Peninsula .
The volume of excavated material arising from the construction of the LSO tunnel will be approximately 571,000 m3.
Of this volume it is expected that approximately 98% will be broken bedrock.
Under relevant waste management legislation the bulk of the material will likely be classified as inert waste.
It is possible that there may be some (relatively small quantity of) hazardous material contained in the overburden material excavated in the made ground at the onshore tunnel inlet shaft – this is to be confirmed by the ongoing Marine SI.
There are no engineering projects available (or proposed within the timescale required by the Ringsend WwTW Extension Project) – of sufficient scale – which would provide a potential outlet for re-use of the excavated spoil material.
The excavated material (broken bedrock component) could have the potential for recycling as an aggregate material. However, this is likely to be very unlikely due to the expected dust content which would render the cost of processing prohibitive.
There are a number of operational licensed soil recovery facilities (quarry restoration) within 30-50 km of the Poolbeg Peninsula which would provide an outlet for the material.
In addition there are a number of other similar facilities which have current licence For inspection purposes only. applications with the EPA. ConsentOne ofof copyright these owneris at required Huntstown, for any other whichuse. is adjacent to the M50 and which has applied for a renewal of a previous licence. The surplus material from the Dublin Port tunnel was disposed at Huntstown. It has sufficient capacity for all of the material from the LSO tunnel. It remains uncertain whether they will obtain their licence within the time frame of the LSO tunnel project.
Disposal at sea to the existing designated spoil dumping ground to the immediate West of Burford Bank is an attractive option as it would significantly reduce the traffic impacts associated with the project. It is also potentially the cheapest of all of the disposal options. However a permit to dispose at this site would have to be obtained from the EPA. The outcome of the application is not certain – though EPA have informally indicated that the reduced cost of this option combined with the significantly reduced volumes of land based HGV traffic would be a consideration in considering the permit consideration.
A permit to dump at Burford Bank would take at least 6 months to process and would require significant supporting data/studies.
The approximate cost of disposing to a licensed soil recovery recycling facility is estimated to be in the range €11.0 million to €17.8 million. Realistically however the costs are likely to be closer towards the upper €17.8 million value than the lower €11.0 million value.
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Transport costs for the land based disposal solutions constitute between 52% and 84% of the total disposal costs.
The approximate cost of disposing at sea (Burford Bank) is estimated to be €10.4 million.
In essence the Burford Bank disposal option provides the most economically advantageous outcome whilst providing a significantly lower HGV traffic impact option compared to other options. 10.2 Possible Actions There are two inter-related key questions which need to be considered by DCC in relation to disposal of spoil from the project and possible actions.
The two questions are:
Are there actions which should be taken which would minimise risk to project delivery and cost?
In view of the potential cost saving and reduction of traffic impacts which could be realised by disposing of material at sea (Burford Bank), should DCC apply for a permit? Minimising Risk The main risk that arises for project delivery is where there is uncertainty regarding the availability of potential suitable outlets - which have the requisite licences in place - for the excavated spoil material. As discussed above, a number of such land based outlets have been identified in the Dublin region. From a planning perspective it is considered that this provides an appropriate solution which can be incorporated within the planning application (EIS) and provides sufficient certainty to project advancement in that context.
It should be noted that in identifying the land based outlet for excavated spoil material from the project in the EIS, it should be highlighted that the construction contract will allow contractors to For inspection purposes only. offer alternative solutions where suchConsent solutions of copyright owneroffer required better for anyvalue other fuse.or money. That will be subject off course to them complying with all relevant legislation and ensuring that the environmental impacts are equal or less than those described in the EIS.
The greater the number of outlets that are in the market to accept the excavated material the more commercial forces will tend to reduce the costs. To reduce the risk of these facilities becoming unavailable in the interim period (and providing certainty), i.e. up to the contract commencement, DCC could consider contracting with a designated land based facility to take excavated material (some or all) from the project. To put this in place DCC would have to go through a procurement process inviting tenders from operators of licensed facilities.
However, given the number of land based outlets that have been identified, the risk of the available market changing significantly in the short term is regarded as being very low. In addition, the gate fees will probably comprise only 20% of the overall disposal costs (i.e. spoil disposal is dominated by transport costs). In addition by providing for a designated land based disposal location in the LSO tunnel contract DCC would be taking on the risk of ensuring the continued availability of that outlet. Therefore, for these reasons it is not recommended that DCC should contract with a soil recovery facility in advance of the LSO tunnelling contract procurement.
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It is not considered that having a contracted land based facility available would reduce the risk in relation to the planning process. In any event the EIS will be completed and submitted to An Bord Pleanala before any procurement process could be completed.
Disposal at Sea – Burford Bank The use of the designated spoil dumping ground at Burford Bank potentially offers a significant reduction in cost to the project. It would require DCC to apply for a sea disposal permit from the EPA.
In addition to the significant potential cost saving there would be a very significant reduction in the traffic impacts which would arise within and around the Ringsend area with land based disposal. Against that there is considerable uncertainty that an application for a sea disposal permit would be successful – there are land based alternatives available and, in comparison with other outlets, it has the lowest priority in the Waste Hierarchy.
However, initial conversations with the EPA have indicated that the onus would be on the applicant to show that there are no practical land based alternatives – which there are. However, the EPA have also indicated that they would be pragmatic and would be willing to take into account issues such as costs and environmental impacts associated with land based spoil disposal as part of any overall assessment for a sea disposal permit for the designated spoil disposal area at Burford Bank.
The preparation cost of an permit application (including miscellaneous studies) is likely to be of an order of as high as €150,000. This cost can however, be expected to reduce significantly depending upon the complexity of discussion/liaison/supporting studies that the EPA require during the license assessment process.
It is considered likely that third party objections to such an application would be received. Interested parties would include fishery organisations and Dublin Port perhaps to a lesser extent.
As the application would take 6 months toFor process,inspection purposes after only. submission, it would not be in place in time Consent of copyright owner required for any other use. for the EIS submission to An Bord Pleanala and hence would offer no benefits in terms of the planning process. Also, if the application processing period was delayed it may not be completed before tenders for the LSO tunnel contact were invited. Notwithstanding these considerations, DCC should consider, in view of the very significant cost and traffic benefits, pursuing a permit application with the EPA. If it were successful it could then be incorporated into the LSO construction contract. In the interim the planning application (EIS) would be based on disposal to a land based facility giving certainty in respect of the planning process, but the EIS would also note the alternative permit application for dumping at sea.
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The relative advantages and disadvantages of the various options are summarised in the following table.
Table 8: Advantages and Disadvantages of Disposal Options
Outlet Advantages Disadvantages Land A number of suitable and licensed outlets are Significant local HGV traffic impacts Based available A number of outlets are licensed ‘soil recovery’ Higher cost compared with sea disposal at Burford facilities – ranks third (of five) in the Waste Hierarchy Bank There is no requirement for DCC to undertake a
separate permitting process Transportation not weather dependent Provides a viable solution for inclusion in the planning application (EIS) and hence provides certainty in respect of planning At Sea Permit Application required – for which detailed data No significant local HGV traffic impacts (Burford and supporting documentation is required Bank) Potentially a significantly lower cost Cost of preparing application €150,000 approx. Jetty facilities already exist at Pigeon House within the 6 month period to process application, i.e. after control and ownership of DCC (Require recertification) submission. Success of Permit Application uncertain Because of the time required to process a Permit Application it is not a stand alone solution that could be included in the planning application.
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10.3 Recommendations The recommendations arising from this study are as follows:
The planning application (EIS) documentation and submissions should be based on utilising a licensed land based disposal outlet. The planning application and EIS will acknowledge that the disposal at sea option is also being pursued.
Further analysis of the soil characteristics from the Marine SI should be incorporated into a project waste management plan (WMP) classifying all the material in respect of its component elements – inert; non-hazardous and hazardous. The WMP should address handling, transportation and disposal.
The contract for the construction of the LSO outfall should include appropriate provisions requiring the contractor to comply with all relevant legislation and the approved EIS and that he should produce a fully developed WMP.
In the EIS, it should highlighted that the construction contract will allow contractors to offer alternative solutions for spoil disposal where such solutions offer better value for money. That will be subject off course to them complying with all relevant legislation and ensuring that environmental impacts are equal or less than those described in the EIS.
The LSO tunnel contract should include provisions which would allow the contractor to source and utilise alternative (licensed) outlets and thereby provide opportunity to offer better value for money – and subject to compliance with the approved EIS.
Further and immediate consultations should be entered into with the Dumping at Sea division of the EPA with regard to assessing the viability of the sea disposal option at the Burford Bank designated spoil disposal area with a view to earliest preparation and submission of an application for an appropriate permit.
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EPA Export 10-12-2012:23:36:45
Appendix C Calculations for Fuel consumption and
Estimated CO2 emissions
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EPA Export 10-12-2012:23:36:45 Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study - Basic Envionmental Cost Benefit Analysis Calculation Sheet
General Value Source
W Total Spoil Volume (m3) 560,300 Dumping at Sea Application X Average Tunnelling per Day (m3 per day) 931 EIS Y Peak Tunnelling Rate (m3 per day) 1,693 EIS Average price of diesel Z Price of Diesel (Euro/Litre) €1.50 on 13/07/12 www.pumps.ie
Truck Value Formula Source Fuel Consumption A Truck Capacity (m3) 8 - Capacity of typical rigid body tipper B Truck load weight (tonnes) 20 - Capacity of typical rigid body tipper C Gross weight of truck (tonnes) 33 - Weight of typical rigid body tipper D Total Truck Trips (No.) 70,038 W/A Max number based on barge capacity. E Fuel Consumption (l/km) @ 50% weight laden 0.288 - Defra, 2005 & Maz Man trucks F Average Distance to Licensed Facility (km) 40 - Spoil Disposal Report G Round Trip to Licensed Facility (km) 80 F*2 H Tonne-km for overall distance that the goods are moved 800 B*F I Tonne-km Round Trip to Licensed Facility 800 (B/2)*G Cargo load reduced for return trip J Total fuel consumption for 1 round trip (l) 23.04 E*G K Total fuel consumption (l) per tonne-km 0.03 J/I L Total fuel cost for 1 round trip (l) €34.56 J*Z M Total fuel cost per tonne-km €0.04 L/I N Total Kms for All Truck Trips (km) 5,603,000 D*G O Total fuel consumption for all trips (l) 1,613,664 E*N P Total cost of Fuel for all trips €2,420,496 O*Z Q Total Tonne-km for all round trips 56,030,000 D*I
CO2-emissions (gCO2 / tonne-km)
R Emissions conversion factors kg CO2 per tonne-km 0.1903 - Defra, 2012 (Rigid truck >17t)
S Total kg CO2 per trip 152 H*R
T Total kg CO2 for all trips 10,662,509 S*D
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Z:\Common\Current Projects\75461_Ringsend_Tunnel\40 Documents Generated\DG 63 Spoil Disposal Options Fuel Costs\EstFuelConsumptionCO2_Final01.xls
EPA Export 10-12-2012:23:36:45 Ringsend WwTW Effluent Outfall Extension Tunnel Spoil Disposal Study - Basic Envionmental Cost Benefit Analysis Calculation Sheet
General Value Source
W Total Spoil Volume (m3) 560,300 Dumping at Sea Application X Average Tunnelling per Day (m3 per day) 931 EIS Y Peak Tunnelling Rate (m3 per day) 1,693 EIS Average price of diesel Z Price of Diesel (Euro/Litre) €1.50 on 13/07/12 www.pumps.ie
Barge Value Formula Source Fuel Consumption A Barge Capacity (m3) 1040 - Irish Dredging Company Based on barge capacity and density of Load Capacity (tonnes) 1500 B - limestone Max number based on barge capacity. Note C Total No. Round Trips required 539 W/A max number based on barge tonnage is 435. D Barge Fuel Consumption (litres/hr) - Steaming 170 - Irish Dredging Company E Barge Fuel Consumption (litres/hr) - Standing 25 - Irish Dredging Company F Barge Speed Loaded (knots) 8 - Irish Dredging Company G Barge Speed Loaded (km/hr) 14.8 F*1.85 H Estimated time for dumping round trip (hrs) - Steaming 2 - Estimate Estimate loading time when idle I Estimated time for loading at quayside (hrs) - Standing 2 - (not total time) J Average Distance to Spoil Disposal Site (km) 10 - Spoil Disposal Report K Tonne-km for overall distance that the goods are moved 15,000 B*J L Tonne-km Round Trip to Spoil Disposal Site 30,000 B*(J*2) Cargo load from the dwt not reduced M Total fuel consumption per trip (l) 390 (D*H)+(E*I) N Total fuel consumption (l) per tonne-km 0.01 M/L O Total fuel cost for 1 round trip (l) €585.00 M*Z P Total fuel cost per tonne-km €0.02 O/L Q Total fuel consumption for all trips (l) 210,113 C*M R Total cost of Fuel for all Trips €315,169 Q*Z S Total Tonne-km for all round trips 16,162,500 C*L
CO2-emissions (gCO2 per tonne-km)
T Emissions conversion factors kg CO2 per tonne-km 0.0292 - Defra, 2012 (Bulk carrier)
U Total kg CO2 per trip 438 K*T
V Total kg CO2 for all trips 235,973 C*U Truck to Jetty Value Formula Source Fuel Consumption For inspection purposes only. a Truck Trip to Jetty (km) Consent of copyright owner required1 for any other use.
b Tonne-km for Truck Trip to Jetty 20 B*a c Total fuel consumption for 1 round trip (l) 0.576 E*(a*2) d Total fuel consumption (l) per tonne-km 0.03 c/b e Total fuel cost for 1 round trip (l) €0.86 c*Z f Total fuel cost per tonne-km €0.04 e/b g Total Kms for All Truck Trips (km) 140,075 D*(a*2) Using same figures for truck calculations h Total fuel consumption for all trips (l) 40,342 g*E i Total cost of Fuel for all trips €60,512 h*Z j Total Tonne-km for all round trips 1,400,750 D*b
CO2-emissions (gCO2 per tonne-km)
k Emissions conversion factors kg CO2 per tonne-km 0.1903 -
l Total kg CO2 per trip 4 k*b
m Total kg CO2 for all trips 266,563 l*D
Barge + Truck to Jetty Value Formula Source Nd Total fuel consumption (l) per tonne-km 0.04 N+d Pf Total fuel cost per tonne-km €0.06 P+f
Ul Total kg CO2 per trip 442 U+l
Vm Total kg CO2 for all trips 502,535 V+m
Z:\Common\Current Projects\75461_Ringsend_Tunnel\40 Documents Generated\DG 63 Spoil Disposal Options Fuel Costs\EstFuelConsumptionCO2_Final01.xls
EPA Export 10-12-2012:23:36:45 For inspection purposes only. Consent of copyright owner required for any other use.
EPA Export 10-12-2012:23:36:45