ARCTIC OFFSHORE TECHNOLOGY ASSESSMENT Xiaobing Shi and Walter Rodriguez American Global Maritime Inc., 11767 Katy Freeway, Suite 660, Houston, TX 77079 This study was funded by the Bureau of Ocean Energy Management, Regulation, and Enforcement, U.S. Department of the Interior, Washington D.C., under Contract Number M10PC00104 Final Report June 2011 This report has been reviewed by BOEMRE and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Bureau, nor does mention of the trade names or commercial products constitute endorsement or recommendation for use BOEMRE Table of Contents TABLE OF CONTENTS SECTION PAGE LIST OF FIGURES............................................................................................................... V LIST OF TABLES .............................................................................................................. VII ACRONYMS AND ABBREVIATIONS .............................................................................. VIII SUMMARY ........................................................................................................................... X 1. TASK1: ASSESSMENT OF ENVIRONMENTAL CONDITIONS .................................. 1 1.1 General .................................................................................................................................................................. 1 1.2 Objective ............................................................................................................................................................... 1 1.3 Wind, Seastate and Current Assessment ........................................................................................................... 1 1.3.1 Beaufort Sea ...................................................................................................................................................... 2 1.3.2 Chukchi Sea....................................................................................................................................................... 5 1.3.3 Dutch Harbor and Captains Bay...................................................................................................................... 13 1.3.4 Norton Basin.................................................................................................................................................... 13 1.4 Air Temperature ................................................................................................................................................ 16 1.5 Ice Cover ............................................................................................................................................................. 19 1.6 Trends.................................................................................................................................................................. 23 1.6.1 Air Temperature .............................................................................................................................................. 23 1.6.2 Ice Break-up & Freeze-up ............................................................................................................................... 26 1.6.3 Sea Ice Extent .................................................................................................................................................. 29 2. TASK2: STUDY OF ABILITIES AND LIMITATIONS OF EQUIPMENT USED TO TRANSPORT PLATFORMS ........................................................................................33 2.1 General ................................................................................................................................................................ 33 2.2 Objective ............................................................................................................................................................. 33 2.3 Class vs. Marine Warranty-Definition and Concept ...................................................................................... 33 2.3.1 Classification and Regulatory Requirements ................................................................................................... 33 2.3.2 Marine Warranty Overview ............................................................................................................................. 34 2.4 Chukchi and Beaufort Sea................................................................................................................................. 35 2.5 Types of Drilling Units ....................................................................................................................................... 36 2.5.1 Jack-ups........................................................................................................................................................... 36 2.5.2 Drillships ......................................................................................................................................................... 37 2.5.3 Drilling Semi-submersibles ............................................................................................................................. 38 PAGE | I BOEMRE Table of Contents 2.5.4 Ice Strengthened Drilling Barges .................................................................................................................... 39 2.5.5 Rigs Operational Perspective .......................................................................................................................... 39 2.6 Drilling Units Geographical Locations ............................................................................................................. 39 2.7 Dry Transportation............................................................................................................................................ 40 2.7.1 General ............................................................................................................................................................ 40 2.7.2 Rig Principal Dimensions ................................................................................................................................ 41 2.7.3 Heavy Lift Market ........................................................................................................................................... 42 2.7.4 Heavy Lift Operators ....................................................................................................................................... 43 2.7.5 Particulars of the Heavy Lift Vessels .............................................................................................................. 48 2.7.6 Particulars of the Heavy Lift Barges ............................................................................................................... 50 2.7.7 Design Criteria and Meteorological Data ........................................................................................................ 51 2.8 Base of Operations ............................................................................................................................................. 52 2.8.1 Port of Nome ................................................................................................................................................... 52 2.8.2 Unalaska, Dutch Harbor .................................................................................................................................. 54 2.8.3 Suitability for Operations ................................................................................................................................ 56 2.9 Float-on /Float-off Operations .......................................................................................................................... 56 2.9.1 Description ...................................................................................................................................................... 56 2.9.2 Float-on Procedure .......................................................................................................................................... 57 2.9.3 Float-off Procedure.......................................................................................................................................... 58 2.10 Wet Transportation ........................................................................................................................................... 59 2.10.1 Towing Operations ......................................................................................................................................... 59 2.10.2 Tug Boat Services........................................................................................................................................... 59 2.10.3 Tug Feasibility ................................................................................................................................................ 60 2.11 Drillship Mobilization ........................................................................................................................................ 63 2.11.1 General............................................................................................................................................................ 63 2.11.2 Anchor Handling Vessels ..............................................................................................................................