The leaky pipeline that led to this summer's market-rattling Prudhoe Bay oil field shutdown was far more severely corroded than initially reported. BP, the company that runs Prudhoe, originally disclosed 16 "anomalies" along the pipe -- places where corrosion had chewed either partly or fully through the steel pipeline wall.
But according to a test report obtained by the Daily News, the three-mile pipeline was infested with 5,476 potential bad spots, including 176 places where corrosion might have chewed through 50 percent or more of the pipe wall. BP's Alaska spokesman and its corrosion manager say the company was surprised by the test results, which were generated by a bullet-shaped electronic device called a smart pig that slides through a pipe looking for bad spots.
A BP contractor, BJ Pipeline Inspection Services, ran the pig through the so-called Flow Station 2 pipeline -- a key trunk line that drains oil out of the eastern side of the sprawling Prudhoe field -- on July 21. Sixteen days later, the pipeline sprang leaks that, coupled with the alarming test report from the pigging run, prompted top BP executives to shut down half of the nation's largest oil field as a precaution, an event that unnerved global oil and gasoline markets.
BP carried out the pig run only after federal pipeline regulators had ordered it to do so.
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