DONG Naturgas A/S BalticPipe, Offshore Pipeline Environmental

4,39

MB

Impact Assessment October 2001

190

stron

3813

ID

DONG Naturgas A/S

2001

rok

Table of contents

1. Introduction 1

1.1 Background for the BalticPipe project 2

1.2 Presentation of the pipeline consortium and operator 3

2. BalticPipe Offshore Pipeline 5

2.1 Routing of the BalticPipe offshore pipeline 5

3. Outline of relevant legislation 9

3.1 Environmental Impact Assessment according to the ESPOO Convention 9

3.2 National legislation and EIA process according to EU Directive 97/11/EC 10

4. Non-technical résumé 15

4.1 Introduction 15

4.2 Pipeline route 15

4.3 Activities during pipeline construction 17

4.4 Pipeline operation 20

4.5 De-commissioning 20

4.6 Environmental Impact Assessment 20

4.7 Transboundary impacts 25

4.8 Mitigation measures 25

5. Technical description of the project 27

5.1 Design basis 27

5.2 Material take-off (M.T.O.) for the BalticPipe 29

5.3 Activities during design/construction 32

5.4 Activities during pre-commissioning 50

5.5 Activities during operation 54

5.6 De-commissioning and abandonment 55

6. Description of the existing offshore environment 57

6.1 General 57

6.2 Landfall locations 57

6.3 Bottom topography, sediment and raw materials 63

6.4 Hydrography 68

6.5 Benthic flora and fauna 72

6.6 Fish and fisheries 76

6.7 Birds 83

6.8 Marine mammals 84

6.9 Protected areas 84

6.10 Classified near-shore areas in Denmark 87

6.11 Tourism and recreational areas 89

6.12 Ship traffic 90

6.13 Cultural heritage 91

6.14 Dumped ammunition/military installations 92

6.15 Existing and planned infrastructure within the project area 98

7. Description of environmental impacts 101

7.1 Methodology 101

7.2 General impacts from the project 101

7.3 Environmental impacts during construction 106

7.4 Sedimentation 110

7.5 Environmental impact during pre-commissioning 135

7.6 Environmental impacts during operation and maintenance 139

7.7 Environmental impact during closing and decommissioning 146

7.8 Transboundary environmental impacts 146

8. Summary of the environmental impact assessment 147

8.1 Environmental impact related to the BalticPipe 147

8.2 Transboundary environmental impacts 150

9. Alternatives 151

9.1 The 0-alternative 151

9.2 Excluded alternative pipeline routes 151

9.3 Pre-commissioning 162

9.4 Alternative materials 169

9.5 Alternative construction methods 173

10. Description of mitigation measures 175

10.1 Introduction 175

10.2 Mitigation measures during pipeline installation 176

10.3 Pre-commissioning 177

10.4 Mitigation measures during operation 177

10.5 Mitigation of impacts on human safety 178

10.6 Mitigating measures during closure and decommissioning 178

11. Difficulties, deficiencies or lack of know-how 179

12. References 181

Appendices

Appendix A Thematic charts (8 pages)

Appendix B Co-ordinates of the pipeline routes (1 page)

Appendix C Material take off (MTO) for the BalticPipe (1 page)

Appendix D Types of construction vessels and equipment (11 pages)

Appendix E Cables in the vicinity of the BalticPipe (2 pages)

Appendix F Fishing gear and fish species (3 pages)

Appendix G Protected areas (3 pages)

Appendix H EEC Habitat area no. 127 and EEC Bird Protection area no. 111

Appendix I Environmental impact from pipe coating and anticorrosion coating

Appendix J Recommendations for Design. Pipe Materials, Girth Welds, Non-destructive Testing,

Coatings and Cathodic Protection Materials

Appendix K Sediment spill and sediment spreading at Rødvig, Avedøre Holme East and at Avedøre

Holme South