NEW YORK - Oil major BP Plc knew as early as 2002 of an "appreciable" buildup of potentially corrosive sediment in a segment of an oil transit pipeline at the Prudhoe Bay oil field that led to the shutdown of the biggest field in the United states in August.
But the company told Alaska regulators that it was "impractical" to clean the pipe with a device that scrapes residue from inside, known as a pig, according to documents obtained by Reuters on Monday. BP was forced to shut down the eastern half of the 400,000 barrels-per-day Prudhoe Bay field in August after a government ordered internal inspection of the segment of pipeline where the sediment had been building up revealed severe corrosion in over a dozen places and several small leaks.
BP's own corrosion detection program, which largely relied on external tools to monitor the state of the pipeline, had not revealed any problems with the line. The shutdown came less than six months after a corroded segment of the western oil transit line ruptured, spilling at least 200,000 gallons of crude oil onto the Arctic tundra, prompting a federal criminal investigation and a US Congressional probe into BP's Alaska operations.
BP's reputation in the United States has been battered by a series of accidents and scandals since March 2005 when a deadly blast at a Texas refinery killed fifteen workers and injured scores more.
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