AN ASSESSMENT OF TECHNIQUES FOR REMOVING OFFSHORE STRUCTURES
Copyright
MARINE BOARD
Preface
BACKGROUND
COMMITTEE COMPOSITION AND SCOPE OF THE STUDY
HOW THE STUDY WAS CONDUCTED
ORGANIZATION OF THE REPORT
ACKNOWLEDGMENTS
REFERENCES
Contents
Executive Summary
CONCLUSIONS
RECOMMENDATIONS
REFERENCE
1Overview of Existing Offshore Structures and Removal Regulations
EXISTING PLATFORMS
Platform Types and Configurations
Free-Standing Caisson with Well(s)
Well-Protector Jackets
Braced Caissons with Well(s)
Conventionally Piled Platforms with Wells
Conventionally Piled Platforms without Wells
Skirt-Piled Platforms
Special Application Platforms
CONSTRUCTION EQUIPMENT USED IN PLATFORM REMOVALS
REGULATIONS, LAWS, AND PERMITS
Federal Laws and Regulations
Outer Continental Shelf Lands Acts
National Environmental Policy Act of 1969
Endangered Species Act
Marine Mammals Protection Act
Other Laws and Regulations
Platform Removal Permit Process
Rigs-to-Reef Program
International Laws
REFERENCES
2 Assessment of Cutting Techniques
EXPLOSIVE CUTTING TECHNIQUES
Present Explosive Cutting Techniques
Bulk Explosive Charges
Configured Bulk Charges
Cutting Charges
Future Explosive Cutting Techniques
Cutting Charges
Fracturing Charges
Other Explosive Charges
NONEXPLOSIVE CUTTING TECHNIQUES
Present Nonexplosive Cutting Techniques
Mechanical Cutters
Abrasive Cutters
Diver Cuts
Future Nonexplosive Cutting Techniques
Hydraulic Shears
Diamond Wire Cutter
TECHNIQUES BEING DEVELOPED
Laser Cutting
Pyrotechnic Cutting
Cryogenics
Chemical Cutters
Deployment of Remotely Operated Vehicles
Bubble Curtains
Acoustic Devices
Platform Design Considerations
REFERENCES
3 Technical Considerations
RECENT REMOVAL PATTERNS
Platform Removals by Water Depth
Platform Removals by Year
Platform Removal Trend
TYPICAL ABANDONMENT PROCESS
Removal Options
Leave-in-Place Option
Partial Removal Option
Topple-in-Place Option
Complete Removal Option
Factors in Selecting Removal Methods
TYPICAL PLATFORM REMOVAL COSTS
REFERENCES
4 Environmental Assessment of Present Removal Techniques
HABITAT AND ECOSYSTEMS
Sea Turtles
Marine Mammals
Fish
NONLETHAL EFFECTS OF EXPLOSIVE REMOVALS
SUMMARY
REFERENCES
5 Summary Assessment of Explosive and Nonexplosive Technologies
FINDINGS
6 Conclusions and Recommendations
CONCLUSIONS
RECOMMENDATIONS
APPENDICES
Appendix A Biographical Sketches of Committee Members
Appendix B Federal Register Notice and List of Respondents
LIST OF RESPONDENTS
Appendix C Participants in Committee Meetings
Houston, Texas
New Orleans (Metairie), Louisiana
Washington, D.C.
Appendix D Regulations Governing Removal of Offshore Structures
FEDERAL STATUTES
INTERNATIONAL LAW
STATE LAW