ANCHORAGE, Alaska (AP) — Members of Congress are calling for an investigation of Royal Dutch Shell PLC's Arctic offshore drilling operations as salvagers develop plans to move a company drill ship off rocks near an Alaska island, where it ran aground in a fierce year end storm.

Shell incident commander Sean Churchfield said Thursday that the first salvage crew on board the Kulluk, a 266-foot diameter barge with a 160-foot derrick, reported back with details that will be used to begin planning. He would not speculate on when a salvage report might be ready.

"There is still a lot of work to do to bring a safe conclusion to this incident," he said.

The vessel is upright and stable, with no indication of a fuel leak, Churchfield said.

The House Sustainable Energy and Environment Coalition, meanwhile, said in a statement that the New Year's Eve grounding should trigger a look at Shell's entire Arctic Ocean drilling operation by the Interior Department and the Coast Guard.

The coalition is made up of 45 House Democrats.

"The recent grounding of Shell's Kulluk oil rig amplifies the risks of drilling in the Arctic," they said in a joint statement. "This is the latest in a series of alarming blunders, including the near-grounding of another of Shell's Arctic drilling rigs, the 47-year-old Noble Discoverer, in Dutch Harbor and the failure of its blowout containment dome, the Arctic Challenger, in lake-like conditions."

The coalition believes these "serious incidents" warrant thorough investigation, the statement said.

Shell Alaska spokesman Curtis Smith said in an email that the company is in full support of, and is providing resources for, the investigation of the grounding by the Unified Incident Command, made up of federal, state and company representatives. Smith said the findings will be available to the public.

The Kulluk is a non-propelled vessel with a reinforced funnel-shaped hull designed to operate in ice. It is carrying more than 140,000 gallons of diesel and about 12,000 gallons of lube oil and hydraulic fluid. It drilled during the short open-water season last year in the Beaufort Sea.

A 360-foot anchor handler, the Aiviq, was towing the Kulluk from Dutch Harbor to Seattle last week for maintenance and upgrades when the tow line snapped south of Kodiak. Lines were reattached at least four times but could not be maintained. A lone tugboat still attached Monday night in a vicious storm couldn't control the vessel and cut it loose as it neared land.

After the grounding, critics quickly asserted it has foreshadowed what will happen north of the Bering Strait if drilling is allowed.

Environmentalists for years have said conditions are too harsh and the stakes too high to allow industrial development in the Arctic, where drilling sites are 1,000 miles or more from the closest Coast Guard base.

Two national organizations kept up the criticism Thursday by calling for a halt to all permitting for Arctic offshore drilling in the wake of the grounding.

"This string of mishaps by Shell makes it crystal clear that we are not ready to drill in the Arctic," said Chuck Clusen of the Natural Resources Defense Council. "Shell is not Arctic-ready. We have lost all faith in Shell, and they certainly don't have any credibility left."

Lois Epstein, a civil engineer who works for The Wilderness Society in Anchorage, said Shell has made troubling, non-precautionary decisions that put workers and the Coast Guard at risk.

"These ongoing technical and decision-making problems and their enormous associated costs and risks taken by our military personnel once there were problems should lead the federal government to reassess its previous permitting decisions regarding Shell," Epstein said.

Shell has maintained it has taken a heads-up approach to anticipating and reacting to problems.

Shell officials say the Kulluk had been towed more than 4,000 miles and has experienced similar storm conditions. Shell staged additional towing vessels along the route in case problems occurred, said Smith, the Shell spokesman.

"We know how to work in regions like this," Smith said. "Having said that, when flawless execution does not happen, you learn from it, and we will."