ANCHORAGE - BP Exploration (Alaska) Inc. has agreed to pay $675,000 to the state to settle claims and cleanup monitoring costs from a pipeline leak on the North Slope last year that spilled crude oil and methanol.
While BP says the spill was 10,000 gallons, the state Department of Environmental Conservation says it may have been as large as 60,000 gallons.
Whatever the amount, BP already has spent more than $2 million cleaning it up, according to company spokesman Paul Laird.
"We don't believe there was any long-term environmental damage," Laird said. State officials said the harm was minimal.
The spill occurred after a valve was inadvertently closed in a 6-inch line that transports oil from one of the Prudhoe Bay production pads to a processing center. That occurred in December of 2000.
"We believe an ice plug put a split in the line," Laird said. "A small amount of oil spilled at that time. Then the ice plug expanded and sealed the crack."
The split was about 11 inches long, according to the DEC.
In February, a crew went out to thaw the line, injecting a mixture of crude oil and methanol, a form of alcohol, according to Leslie Pearson of DEC. That melted the ice plug, so oil and methanol began spewing out. The leak wasn't detected until technicians noticed a discrepancy in the amount of liquid coming out the other end, Pearson said.
About half of the money BP is paying will go into a spill mitigation account. But $300,000 will be used for a pollution mitigation project.
State officials have their eye on using the money to start using low-sulfur diesel fuel in Alaska school buses.