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Liberty: ERD wells using Badami facilities BP project manager for field says decision made in August to focus on drilling from shore; no rig in Alaska could drill these wells Kristen Nelson Petroleum News Editor-in-Chief
The plan early in this decade was to develop Liberty as a twin to Northstar, Darryl Luoma, BP Exploration (Alaska)’s Liberty project manager, said Oct. 19.
Both fields lie in shallow Beaufort Sea waters off Alaska’s North Slope, Northstar north of Prudhoe Bay and Liberty farther east, between Endicott and Badami.
But Northstar development more than doubled in cost and ran two years behind schedule, and the original Liberty project concept was cancelled in 2002, he said. Over the next two years BP screened other ways to develop Liberty, including from onshore. In early 2005, management asked for a re-look at a shore-based development, Luoma told an Alaska Oil and Gas Association project conference, and in August the decision was made to proceed with development from shore using extended reach drilling, a technology BP has used successfully at its Wytch Farm development in southern England. There has also, Luoma said, been “continued industry progress” in ERD technology, including Exxon wells at Sakhalin. Pushing the envelope Liberty would push the BP ERD drilling envelope: The Wytch Farm wells go out more than 30,000 feet in equivalent departure to true vertical depths of some 6,000 feet; Liberty wells would have to go out from some 25,000 to more than 40,000 feet with true vertical depths just above 10,000 feet. Northstar wells, with a reservoir at about the same depth, have equivalent departures in the 5,000 to almost 20,000-foot range with Niakuk ERD wells setting Alaska records at close to 20,000 feet.
Point Brower is a possibility for a shore drilling pad, as are other sites farther east.
Luoma said the project was likely to need a different rig, because the ERD drilling limitation on the North Slope is the existing rig fleet. The drilling rig needed is likely a key critical path in the timeline for the project, which, if it moves ahead, would begin in the fourth quarter of this year with agency and stakeholder discussions, proceed to conceptual engineering next year, preliminary engineering and regulatory work in 2007 and permits in 2008. Procurement, fabrication and construction would be in 2008-10, with rig mobilization and first drilling in 2010 and first oil in 2011.
Luoma said a production pad at Point Brower would likely be connected by road to the Endicott Road.
A recent BP ERD workshop looked at well difficulties, and didn’t find any showstoppers at Liberty. The biggest drilling challenge, he said, is getting through geologic zones. The Wytch Farm wells took as long as 140 days to drill; the estimate for Liberty wells is plus or minus 120 days.
Editor’s note: See related Liberty story on page 1 of last week’s Petroleum News.
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