Only a day after Shell Alaska began drilling a landmark offshore oil well in the Arctic, the company was forced on Monday to pull off the well in the face of an approaching ice pack.
With the ice floe about 10 miles away, the Noble Discoverer drilling rig was disconnecting from its seafloor anchor Monday afternoon in the Chukchi Sea, about 70 miles from the northwest coast of Alaska.
Company ice trackers had been carefully monitoring ocean ice and, when the wind direction changed and the ice floe began moving closer, they advised that the rig shut down and disconnect from the well, Shell spokeswoman Kelly op de Weegh told the Los Angeles Times.
Op de Weegh said that the ice floe, 30 miles long and about 10 miles wide, wasn't an immediate threat but that engineers elected to halt operations as a precaution.
"The Arctic if anything is dynamic," she said. "That's why we have the capabilities we have to monitor sea ice, as well as the ability to safely alter our operations."
She said it could take several days for the ice to move and allow Shell to resume drilling.
Shell began only early Sunday plumbing the top hole of its first offshore Arctic well in two decades, located over a large undersea oil reserve known as the Burger prospect.
The company had hoped to launch operations much earlier in the summer but was delayed in part by unusually large volumes of sea ice, which moved off the coast of Alaska much later this year than in other recent summers.
Shell has also been delayed by lingering problems with its oil spill containment barge, the Arctic Challenger, which has been undergoing a complex retrofit in Bellingham, Wash.
The federal Bureau of Safety and Environmental Enforcement will not allow Shell to drill deep enough to reach hydrocarbon deposits until the Challenger is certified by the U.S. Coast Guard and on-site in the Arctic.
On Monday, the barge pulled out of the dock for the first time and was undergoing sea trials, which could take several days, Op de Weegh said.
[For the record, 5:39 p.m. Sept. 10: An earlier version of this post called the Bureau of Safety and Environmental Enforcement the Bureau of Environmental Enforcement.]