PICKERILL ALPHA (A) & BRAVO (B) INSTALLATIONS DECOMMISSIONING PROGRAMME (REMOVAL PHASE) ENVIRONMENTAL APPRAISAL – SN-CX-XX-AT-XS-000001 #8 2019 Pickerill Alpha (A) & Bravo (B) Installations Decommissioning Programme (Removal Phase) Environmental Appraisal SN-CX-XX-AT-XS-000001 PERENCO 3 Central Avenue | St Andrews Business Park Norwich | Norfolk | NR7 0HR PERENCO PICKERILL ALPHA (A) & BRAVO (B) INSTALLATIONS DECOMMISSIONING PROGRAMME (REMOVAL PHASE) ENVIRONMENTAL APPRAISAL – SN-CX-XX-AT-XS-000001 DOCUMENT CONTROL Document reference number: SN-CX-XX-AT-XS-000001 REVISION RECORD Date Rev no. Description Prepared by Checked by Approved by 25/01/2019 R01 Issued to client N Lacey G Jones R Allan for review 22/02/2019 A01 Issued for Use G Jones J Smith R Allan 06/03/2019 A02 Re-Issued for G Jones R Allan R Allan Use A.Fowler G.MacGlennon (Perenco) (Perenco) 05/06/2019 A03 Addressing H. Nagle J.Summerell A.Fowler OPRED (Perenco) (Perenco) Comments 14/06/2019 A04 Consultation J.Summerell A.Salzgeber A. Salzgeber Draft PERENCO PICKERILL ALPHA (A) & BRAVO (B) INSTALLATIONS DECOMMISSIONING PROGRAMME (REMOVAL PHASE) ENVIRONMENTAL APPRAISAL – SN-CX-XX-AT-XS-000001 TABLE OF CONTENTS Non-technical summary ........................................................................................................................ i Background to the Project .............................................................................................................. iii Impact Assessment ........................................................................................................................... i Summary of Assessment ............................................................................................................... i Control and Mitigation Measures ............................................................................................... iii Introduction ................................................................................................................................. 1 Overview of the Infrastructure.............................................................................................. 1 Purpose of Document............................................................................................................ 2 Regulatory Context ................................................................................................................ 3 Stakeholder Consultation ............................................................................................................. 5 Decommissioning Activities and Parameters............................................................................... 9 Description of Infrastructure Being Decommissioned .......................................................... 9 Consideration of Alternatives and Selected Option ............................................................ 11 Description of Decommissioning Activities ......................................................................... 12 Post-Decommissioning Activities ........................................................................................ 12 Schedule .............................................................................................................................. 13 Summary of Materials Inventory ........................................................................................ 15 Waste Management ............................................................................................................ 17 3.7.1 Contractor Management ............................................................................................. 17 3.7.2 Measuring and Monitoring Performance .................................................................... 18 Environmental Management .............................................................................................. 18 3.8.1 Scope of SEMS .............................................................................................................. 18 3.8.2 Principle of the SEMS ................................................................................................... 19 Environmental and Societal Baseline ......................................................................................... 21 Introduction ......................................................................................................................... 21 Physical Environment .......................................................................................................... 21 4.2.1 Bathymetry ................................................................................................................... 21 4.2.2 Seabed Sediments ........................................................................................................ 21 4.2.3 Sediment Chemistry ..................................................................................................... 24 PERENCO PICKERILL ALPHA (A) & BRAVO (B) INSTALLATIONS DECOMMISSIONING PROGRAMME (REMOVAL PHASE) ENVIRONMENTAL APPRAISAL – SN-CX-XX-AT-XS-000001 4.2.4 Waves ........................................................................................................................... 25 4.2.5 Water Circulation and Tides ......................................................................................... 25 4.2.6 Temperature and Salinity ............................................................................................. 26 Biological Environment ....................................................................................................... 26 4.3.1 Benthic Fauna ............................................................................................................... 26 4.3.2 Plankton ....................................................................................................................... 28 4.3.3 Fish and Shellfish .......................................................................................................... 28 4.3.4 Seabirds ........................................................................................................................ 30 4.3.5 Marine Mammals ......................................................................................................... 36 4.3.6 Protected Species ......................................................................................................... 39 4.3.7 Conservation Areas ...................................................................................................... 39 4.3.8 National Marine Plans / East Inshore and East Offshore Marine Plans ...................... 46 Societal ................................................................................................................................ 48 4.4.1 Commercial Fisheries ................................................................................................... 48 4.4.2 Oil and Gas Activities.................................................................................................... 52 4.4.3 Aggregate Extractions, Offshore Renewables and Carbon Capture and Storage ....... 55 4.4.4 Commercial Shipping ................................................................................................... 56 4.4.5 Telecommunications and Cabling ................................................................................ 59 4.4.6 Military Activity ............................................................................................................ 60 4.4.7 Wrecks .......................................................................................................................... 60 Environmental Issues Identification summary and Impact Assessment Methodology ............ 61 Risk Assessment Methodology ............................................................................................ 61 Risk Assessment Findings .................................................................................................... 62 Environmental and Societal Assessment ................................................................................... 66 Seabed Impacts ................................................................................................................... 66 6.1.1 Approach ...................................................................................................................... 66 6.1.2 Sources of Potential Impacts ....................................................................................... 66 6.1.3 Short and Long-Term Impacts ...................................................................................... 69 6.1.4 Short-Term Impacts on Sensitive Receptors ................................................................ 69 6.1.5 Long-Term Impacts on Sensitive Receptors ................................................................. 71 PERENCO PICKERILL ALPHA (A) & BRAVO (B) INSTALLATIONS DECOMMISSIONING PROGRAMME (REMOVAL PHASE) ENVIRONMENTAL APPRAISAL – SN-CX-XX-AT-XS-000001 6.1.6 Cumulative and Transboundary Impact ....................................................................... 72 6.1.7 Proposed Mitigation Measures .................................................................................... 72 6.1.8 Conclusion .................................................................................................................... 73 Accidental Events ................................................................................................................ 75 6.2.1 Hydrocarbon Releases