Inquiry launched after pump station accident

The company that runs the pipeline acknowledges a fire or explosion, had the gas ignited, could have imperiled the station's 60-plus workers and caused "an extended shutdown" of oil fields that pump huge dollars into the state treasury.

Federal and state regulators as well as congressional offices are scrutinizing the Jan. 15 incident, and BP and Alyeska Pipeline Service Co. each are conducting extensive internal reviews of what went wrong at Pump Station 1.

BP runs Prudhoe Bay, the nation's largest oil field, and Anchorage-based Alyeska is the energy company consortium that operates the 800-mile pipeline.

The incident occurred as BP workers used a cleaning device called a pig to swab oil out of an old pipeline the company was preparing to decommission. The pipe, 34 inches in diameter, was among major Prudhoe trunk lines found in 2006 to be ravaged with corrosion due to BP's admitted lack of proper maintenance.

The pigs typically are shaped like oversized bullets, ringed with discs that scrape the inside wall of a pipe as they slide through.

BP's workers were using pressurized natural gas to push their pig through the pipeline.

At some point, the pig got stuck and the workers "lost track of its exact location" along the pipeline, says a preliminary investigative report Alyeska prepared for regulators.

A large volume of gas then bypassed the pig somehow and rushed to Pump Station 1, a key asset through which every drop of oil coming off the North Slope must pass.

The gas caused the station's pumps to "overspeed" and shut down. Incoming oil and gas was diverted into two huge storage tanks adjacent to the pump station.

Large volumes of gas escaped out relief vents and hatches into the air. Some burned in a safety flare near the tanks.

The pump station shut down for more than half an hour, from 3:06 p.m. to 3:41 p.m. Workers were ordered to evacuate some areas.

The incident had potential to injure the 63 workers who were there at the time, and to knock out Pump Station 1 for an extended time, Alyeska's report says.

The potentially catastrophic incident alarmed regulators as well as BP and Alyeska workers. Everyone at the pump station was asked to submit to interviews as part of the investigation.

Asked Friday what could have happened at worst, federal pipeline regulator Jerry Brossia said: "Burn Pump Station 1 down."

Spokespersons for BP and Alyeska on Friday acknowledged the close call.

"It was a very serious event," said Alyeska's Michelle Egan.

Alyeska's report faults BP -- itself a nearly 50 percent owner of Alyeska -- for mistakes leading up to the Pump Station 1 incident:

• In planning the cleanup of the old pipe, BP didn't consider a scenario of the pig getting stuck or stalled, or the "possibility of significant gas breakthrough."

• BP planners failed to involve Alyeska workers who understand the pump station's equipment and operation.

The incident shows that oil producers need to work more closely with the trans-Alaska pipeline operator, Brossia said.

BP spokesman Steve Rinehart conceded lapses. Although BP did a safety analysis prior to its pigging operation, the analysis was "flawed" and no burst of natural gas was supposed to reach Pump Station 1, he said.

BP also needs to tighten its work with the pipeline operator, Rinehart said.

"We're going to use this incident to improve our practices and our procedures and to enhance our communications with Alyeska," he said.

Alyeska's Egan said her company first informed regulators of the Pump Station 1 incident on Jan. 20, five days after it happened.

Several agencies are investigating including Brossia's Joint Pipeline Office, an Anchorage umbrella agency for federal and state regulators who oversee Alaska pipelines. Also involved is the U.S. Pipeline and Hazardous Materials Safety Administration, which was critical of BP for its pipeline corrosion problems.

Congressional offices with oversight over energy development and safety also are looking at the matter, the BP and Alyeska spokespersons said.

Find Wesley Loy online at adn.com/contact/wloy or call 257-4590.