By Yereth Rosen

ANCHORAGE, Alaska (Reuters) - A large drill ship belonging to oil major Shell ran aground off Alaska on Monday night after drifting in stormy weather, company and government officials said.

The ship, the Kulluk, broke away from one of its tow lines on Monday afternoon and was driven to rocks just off Kodiak Island, where it grounded at about 9 p.m. Alaska time, officials said.

The 18-member crew had been evacuated by the Coast Guard late Saturday because of risks from the storm.

With winds reported at up to 60 miles an hour and Gulf of Alaska seas of up to 35 feet, responders were unable to keep the ship from grounding, said Coast Guard Commander Shane Montoya, the leader of the incident command team.

"We are now entering into the salvage and possible spill-response phase of this event," Montoya told a news conference late on Monday night in Anchorage.

There were three minor injuries to people responding to the incident but all personnel have returned to duty.

There is no known spill and no reports of damage yet and a U.S. Coast Guard helicopter overflight conducted shortly after the grounding detected no visible sheen.

A spokeswoman for the command team said it would do another overflight during daylight on Tuesday, weather permitting.

The Kulluk has about 139,000 gallons of ultra-low-sulfur diesel on board, and equipment on the Kulluk is estimated to have about 12,000 gallons of combined lube oil and hydraulic fluid.

The grounding of the Kulluk, a conical, Arctic-class drill ship weighing nearly 28,000 gross tons, is a blow to Shell's $4.5 billion offshore program in Alaska.

Shell's plan to convert the area into a major new oil frontier has alarmed environmentalists and many Alaska Natives, but excited industry supporters.

Environmentalists and Native opponents say the drilling program threatens a fragile region that is already being battered by rapid climate change.

"Shell and its contractors are no match for Alaska's weather and sea conditions either during drilling operations or during transit," Lois Epstein, Arctic program director for The Wilderness Society, said in an email.

"Shell's costly drilling experiment in the Arctic Ocean needs to be stopped by the federal government or by Shell itself given the unacceptably high risks it poses to both humans and the environment," she added.

The nearest town is Old Harbor, located on the opposite side of Kodiak Island from where the Kulluk is grounded. Old Harbor is a Native Alutiiq village with 208 residents.

The leading Democrat on the U.S. House of Representatives' Natural Resources Committee, Ed Markey, of Massachusetts, said in a statement that this incident and others illustrated the perils of oil drilling in the Arctic.

"Oil companies cannot currently drill safely in the foreboding conditions of the Arctic, and drilling expansion could prove disastrous for this sensitive environment," he said. Continued...