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Shell begins drilling in Chukchi Sea

Pete Slaiby, vice president of Shell Alaska.

Pete Slaiby, vice president of Shell Alaska.

ANCHORAGE — More than four years after Royal Dutch Shell paid $2.8 billion to the federal government for petroleum leases in the Chukchi Sea, a company vessel on Sunday morning sent a drill bit into the ocean floor, beginning preliminary work on an exploratory well 70 miles off the northwest coast of Alaska.

Drilling began at 4:30 a.m., said Shell Alaska spokesman Curtis Smith. Shell Alaska vice president Pete Slaiby called it historic.

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‘‘It’s the first time a drill bit has touched the sea floor in the US Chukchi Sea in more than two decades,’’ Slaiby said in a prepared statement. ‘‘This is an exciting time for Alaska and for Shell. We look forward to continued drilling progress throughout the next several weeks and to adding another chapter to Alaska’s esteemed oil and gas history.’’

Federal officials estimate Arctic waters in the Chukchi and Beaufort seas hold 26 billion barrels of recoverable oil and 130 trillion cubic feet of natural gas. Interior Secretary Ken Salazar announced Aug. 30 that Shell would be permitted to begin preparation work at the Chukchi site even though the company’s spill response barge has not been certified and is not positioned nearby.

The company is authorized to drill narrow pilot holes 1,400 feet below the ocean floor and roughly 4,000 feet above a petroleum reservoir.

Shell has spent upward of $4.5 billion for Arctic Ocean drilling but had been thwarted from drilling by environmental lawsuits, regulatory requirements, and short open-water drilling seasons. Despite the requirement to stay out of oil-bearing rock, they were elated to finally begin work.

Drilling is bitterly opposed by environmental groups that say oil companies have not demonstrated they can clean up a spill in ice-choked water. They say a spill of the magnitude of the Deepwater Horizon blowout in the Gulf of Mexico would be catastrophic in a region hammered by climate warming and home to endangered or threatened marine mammals such as bowhead whales, polar bears, and walruses.

Shell officials say there is little chance of that happening. They are drilling in about 130 feet deep, vs. 5,000 at the site of the gulf spill, and wellhead pressure is expected to be far less.

The oil spill response barge remains in Bellingham, Wash., and is expected to undergo sea trials over the weekend, Smith said.

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