In the midst of cleaning up a major North Slope oil spill with an unusual twist, BP has reported another spill involving a different pipeline.
Officials estimated Wednesday's spill at more than 7,000 gallons of what's known as produced water, the water pumped with oil from wells and then separated from crude at processing centers. BP Exploration (Alaska) Inc. discovered the spill at about 1:40 p.m. Wednesday and reported it to the state Department of Environmental Conservation about an hour later.
A cause has not been determined.
The spill is the second since Sunday involving pipelines managed by BP. The Sunday oil spill still is being cleaned up as well. Officials say they have not pinpointed a cause or estimated the size of that spill.
The oil and water found leaking Sunday formed an odd, bumpy mound 5 feet tall, kind of like what might squirt out of a giant frozen-treat machine, state and federal environmental officials on the scene said Thursday in a teleconference briefing for reporters.
"One thing I will tell you, most interesting about this spill is the nature of the spill material. It is doing something that many of us seasoned responders have never seen before," said Matt Carr, the on-scene coordinator for the U.S. Environmental Protection Agency. "You have this large dome of semi-solid material. The best way I can describe it is like a very stiff Slurpee or a very stiff snow cone."
Carr, who said he has responded to many spills in his 26-year career, called the mounded material a first.
Workers using shovels, bins and snowmachines finished clearing oil-misted snow on Tuesday but most of the heavily contaminated snow still must be hauled away.
The 18-inch flow line to the Lisburne Processing Center carried a mix of crude, natural gas and produced water. BP spokesman Steve Rinehart said the line had been out of operation for a few weeks because of ice plugs but that details such as exactly when the flow was shut down are part of the ongoing investigation into the leak's cause.
Night crews on Wednesday laid down portable wooden platforms to use as a staging area. Crews also are building an ice pad about a mile and a half away where the contaminants will be melted, measured and recycled, said Randy Selman, BP incident commander. Recovered oil will be put back into production, according to BP.
A safety zone about 40 feet in diameter is centered on the leak site. So far, oil cleanup crews aren't going into the safety zone. BP is X-raying the 18-inch pipe to look for ice plugs and pockets of gas, Selman said. Once officials have more information, they'll be able to safely direct cleanup crews, according to the command team.
The Wednesday spill was from a 6-inch line carrying produced water inside a manifold building where different pipes come together, according to the state Department of Environmental Conservation.
BP estimated that about 5,040 gallons remained inside the building, while 2,100 spilled onto the gravel production pad, known as R Pad. The liquid was sucked into a vacuum truck but some of the water froze. It will be removed with a jackhammer or by being flushed with more water.