ANCHORAGE - An equipment failure has halted production at Northstar, an island oil field in the Beaufort Sea, and repairs could take as long as three weeks, according to officials with BP Exploration (Alaska) Inc. said.
The failure, which occurred Sunday, interrupts the flow of an average 72,000 barrels of crude oil per day, about 7 percent of all North Slope production.
The problem was a failed compressor motor, said Daren Beaudo, spokesman for BP, which operates the field. The motor is part of a chain of equipment that injects natural gas back underground.
The gas, which comes out of wells mixed with oil, is reinjected to pressure out more oil. Also, there's no pipeline to carry the gas to market.
The shutdown is the second at Northstar since last fall when an electrical transformer failed, bringing the field to a near halt for several days.
Like the fall incident, this latest problem means moving a replacement part of perhaps 25,000 pounds into place, Beaudo said. That's not easy at Northstar, where work space is limited and equipment is packed tightly on a five-acre artificial island about six miles northwest of Prudhoe Bay.
"It's going to take a lot of planning and maneuvering to do it safely," Beaudo told the Anchorage Daily News. "Fortunately, we do have a replacement motor on the island. But we've got to fit it like a jigsaw piece into the surrounding equipment and structure."
The failure comes on the heels of the field's single-day production record of nearly 85,000 barrels set on Jan. 26.
BP could have sought regulatory permission to keep production going by flaring, or burning, the gas. But the company decided against that idea, which would have released pollutants into the air.
"We felt the environmental consideration outweighed the economic consideration," Beaudo said.
Northstar is a relatively new oil field, starting production November 2001. It contains an estimated 175 million barrels of recoverable oil.