OCS Study MMS 2004-074 Operational and Socioeconomic Impact of Nonexplosive Removal of Offshore Structures U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region OCS Study MMS 2004-074 Operational and Socioeconomic Impact of Nonexplosive Removal of Offshore Structures Preparers Twachtman Snyder & Byrd, Inc. and Center for Energy Studies Louisiana State University Prepared under MMS Purchase Order 0302 PO 57597 by Twachtman Snyder & Byrd, Inc. 13105 Northwest Freeway, Suite 800 Houston, Texas 77040 and Center for Energy Studies Louisiana State University Energy Coast and Environment Building Nicholson Extension Drive Baton Rouge, Louisiana 70803-0301 Published by U.S. Department of the Interior Minerals Management Service New Orleans Gulf of Mexico OCS Region November 2004 DISCLAIMER This report was prepared under a purchase order between Twachtman Snyder & Byrd, Inc. and the Minerals Management Service (MMS). This report has been technically reviewed by MMS and has been approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of MMS, nor does mention of trade names or commercial products constitute endorsement or recommendations for use. It is, however, exempt from review and compliance with MMS editorial standards. REPORT AVAILABILITY Extra copies of this report may be obtained from the Public Information Office (Mail Stop 5034) at the following address: U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region 1201 Elmwood Park Boulevard New Orleans, Louisiana 70123-2394 Telephone Numbers: (504) 736-2773 1-800-220-GULF CITATION This study should be cited as: Twachtman Snyder & Byrd, Inc. and Center for Energy Studies, Louisiana State University. 2004. Operational and Socioeconomic Impact of Nonexplosive Removal of Offshore Structures. U.S. Dept. of the Interior, Minerals Management Service, Gulf of Mexico OCS Region, New Orleans, LA. OCS Study MMS 2004-074. 50 pp. iii TABLE OF CONTENTS Page FIGURES....................................................................................................................................................vii TABLES ......................................................................................................................................................ix 1. EXECUTIVE SUMMARY.....................................................................................................................1 2. THE BUSINESS OF DECOMMISSIONING........................................................................................3 2.1. The Management of Decommissioning Activities......................................................................3 2.2. The Bid Process and Contractor Selection..................................................................................3 2.3. The Decommissioning Network in the Gulf of Mexico..............................................................6 2.4. Nonexplosive Severance Contractors .........................................................................................6 2.5. The Cutting Season is Short......................................................................................................11 3. FACTORS INVOLVED IN SEVERANCE SELECTION...................................................................13 3.1. Direct Cost ................................................................................................................................13 3.2. Cost of Failure...........................................................................................................................13 3.3. Safety Issues..............................................................................................................................13 3.4. Environmental Issues and Structure Disposition ......................................................................14 3.5. Operator Preference ..................................................................................................................14 3.6. Operational Scheduling.............................................................................................................14 3.7. Structural Characteristics ..........................................................................................................15 3.8. Structure Age ............................................................................................................................16 3.9. Reliability..................................................................................................................................16 3.10. Configuration Type...................................................................................................................16 4. THE VALUE OF CUTTING SERVICE PER DECOMMISSIONING AND ONSHORE ALLOCATION ....................................................................................................................................19 5. THE STRUCTURE OF NONEXPLOSIVE SERVICE CONTRACTS...............................................23 5.1. The Elements of a Standard Service Contract...........................................................................23 5.2. Job and Contract Specification .................................................................................................25 5.3. Total Cost Functionals ..............................................................................................................25 5.4. Parameter Specification ............................................................................................................26 6. THE SCIENCE AND TECHNOLOGY OF NONEXPLOSIVE REMOVAL METHODS.................27 6.1. Mechanical Methods.................................................................................................................27 6.2. Abrasive Methods .....................................................................................................................28 6.3. Diamond Wire Methods............................................................................................................30 6.4. Diver Torch Methods................................................................................................................32 7. NONEXPLOSIVE CUTTING SYSTEMS AND ACTIVITY REQUIREMENTS .............................33 7.1. Mechanical Systems..................................................................................................................33 7.2. Abrasive Water Jet Systems......................................................................................................33 7.3. Diamond Wire Systems ............................................................................................................33 7.4. Diver Torch Systems.................................................................................................................33 v 8. ENVIRONMENTAL AND SAFETY ISSUES....................................................................................35 8.1. Environmental and Physical Impact .........................................................................................35 8.2. Safety Issues..............................................................................................................................35 9. JACKET HOPPING .............................................................................................................................36 9.1. Methodology Description .........................................................................................................37 9.2. Frequency of Use ......................................................................................................................37 9.3. Feasibility of Methodology.......................................................................................................38 9.4. Equipment and Personnel Requirements ..................................................................................38 9.5. “Shallowing-Up” Path Determination ......................................................................................38 9.6. Accidents/Incidents...................................................................................................................38 9.7. Economic Factors......................................................................................................................38 10. SUMMARY AND CONCLUSIONS ...................................................................................................41 10.1. Summary of Nonexplosive Removal of Offshore Structures (NEROS) Severing Option Limitations ................................................................................................................................41 10.2. Other Primary Conclusions.......................................................................................................41 11. GLOSSARY OF TERMS FREQUENTLY USED IN OFFSHORE CONSTRUCTION AND DECOMMISSIONING ........................................................................................................................43 12. REFERENCES .....................................................................................................................................49 vi FIGURES Page Figure 2.1. Bid and Contractor Selection Process.....................................................................................5 Figure 2.2. Decommissioning Network in the Gulf of Mexico.................................................................7 Figure 2.3. Gulf of Mexico Heavy Lift Vessels