* Drilling this year was more limited than planned
* Federal plan allows 10 wells over two seasons
By Yereth Rosen
ANCHORAGE, Alaska, Oct 31 (Reuters) - Royal Dutch Shell Plc said on Wednesday it has finished exploration drilling for the season in Arctic waters off Alaska and was moving drill ships and equipment south for the winter, in accordance with federal permits.
Its work was the first in two decades in the federal Arctic program, even though it ended up being much more limited than initially planned. This was due to setbacks for the company that environmentalists seized upon as potential pitfalls inherent in drilling in the Arctic.
Shell capped the two wells it started in the Chukchi and Beaufort seas and was moving equipment out, while also preparing to return for more drilling next year, said Shell spokesman Curtis Smith.
“We will revisit these wells as soon as the ice permits in 2013,” Smith said. Shell expects to complete the two wells to oil-bearing depths and then drill additional wells in both seas next year, he added.
Shell had hoped to drill up to three wells in the Chukchi and up to two in the Beaufort. But lingering pack ice delayed vessel movement into Arctic waters, and problems with a mandatory oil-spill barge also curbed this year’s efforts.
The barge, the Arctic Challenger, failed to win U.S. Coast Guard approval until this month, while its oil-containment system was damaged in September sea trials in the Puget Sound.
With the barge unavailable, Shell was only allowed to do “top-hole” drilling, or down to about 1,500 feet, thousands of feet short of geologic zones known to contain oil and gas.
With Coast Guard approval now in hand and repairs under way, the Arctic Challenger is expected to be at the drill sites next year, allowing Shell to penetrate deep into the oil-bearing rock and to make and evaluate discoveries, Smith said.
The federally approved exploration plan allows up to a total of 10 wells over the two seasons, he said, but it has yet to be seen whether Shell will be able to drill that many. “It’s not a number that we’re fixated on,” Smith said. “Our goal is to drill safely and responsibly, but also to gather data.”