BILLINGS, Mont. — Delays in Exxon Mobil Corp.’s response to a pipeline break beneath Montana’s Yellowstone River made an oil spill far worse than it otherwise would have been, federal regulators said in a new report.
The July 2011 rupture fouled 70 miles of riverbank along the scenic Yellowstone, killing fish and wildlife and prompting a monthslong cleanup.
The damage could have been significantly reduced if pipeline controllers had acted more quickly, according to Department of Transportation investigators.
The report, provided to The Associated Press by the office of U.S. Sen. Max Baucus, D-Mont., marks the first time federal regulators have highlighted specific actionsby Exxon as contributing to the severity of the spill.
An Exxon spokesman said Wednesday that the company was reviewing the findings.
The spill released about 1,500 barrels of crude into the river near the city of Laurel. A barrel is 42 gallons.
The damage would have been reduced by about twothirds if controllers in Houston isolated the rupture as soon as problems emerged, investigators said.
Instead, as Exxon personnel weighed the appropriate response, crude drained from the severed, 12-inch pipeline for another 46 minutes before a control valve was finally closed.
Exxon spent $135 million on its response to the spill, including cleanup and repair work.
Spokesman Rachael Moore said the company willcontinue to cooperate with Pipeline and Hazardous Materials Safety Administration and “is committed to learning from these events.”
The report chalks up the immediate cause of the spill to floodwaters that damaged the pipeline and left it exposed. Debris washing downriver piled up on the line, increasing pressure until it ruptured.
The “volume would have been much less” and the location of spill “would have been identified far more quickly” if Exxon’s emergency procedures had called for the immediate closure of upstream valves, investigators said.
The report also faulted Exxon for lacking a plan to notify pipeline controllers that the river was flooding.
Exxon workers were not blamed, however, for stepstaken in the lead-up to the spill.
City officials in Laurel had warned Exxon that the riverbank was eroding.
Exxon’s field observations and “depth of cover survey took reasonable precautions to address the flooding of the Yellowstone River it the spring and early summer of 2011,” the investigators wrote.
The report did not address concerns raised by Baucus and other lawmakers over whether existing pipeline regulations do enough to prevent spills at river crossings.
Under current rules, companies must bury pipelines 4 feet beneath a riverbed and inspect them periodically. Those rules are being reviewed, and Baucus said Wednesday that “transparency and oversight are critical to making sure we never have to go through the devastation of the Yellowstone River oil spill again.”
In the Exxon case, a section of pipeline leading away from the river was buried more than 6 feet deep. During repair work after the spill, the pipeline was reinstalled dozens of feet beneath the riverbed.
Landowners along the river have sued Exxon, saying the company didn’t do enough to prevent the spill and should have shut down the line during flooding. Exxon is fighting the lawsuits.
The federal investigation into the spill remains open. Whether any citations will be issued is under review, said Damon Hill, spokesman with the Department of Transportation’s Pipeline and Hazardous Materials Safety Administration.
Front Section, Pages 4 on 01/03/2013