A Royal Dutch Shell PLC drill vessel aground off a remote Gulf of Alaska island is upright and stable but has suffered damage to generators and its upper deck.
Shell incident commander Sean Churchfield says a salvage team found open hatches that allowed water to enter the Kulluk, which drilled in the Beaufort Sea during the 2012 open water season.
The Coast Guard says there's no indication of a fuel leak.
The drilling barge ran around Monday night after it lost a line to its main towing vessel and couldn't be controlled by a tugboat.
Churchfield says damage to the barge's generators means salvagers may have to bring external generators on board or work without power.
He says the salvage is in the assessment stage and it's too early to tell when the vessel can be moved.
Two national environmental groups are calling for a halt to federal permits for Arctic offshore petroleum drilling after the grounding of a the Kulluk.
The Natural Resources Defense Council and The Wilderness Society say Shell has demonstrated it's not ready to drill in Arctic waters.
They say the risks are too large to make mistakes in what they consider one of the most fragile places on earth.
In addition, Members of Congress are now calling for an investigation.
A U.S. House coalition says it's calling on the Interior Department and the Coast Guard to jointly investigate the New Year's Eve grounding of the Kulluk and other incidents.