"As many as 80 workers were hustling Monday to clean up oily water in what ranks as one of the largest industrial spills ever seen in the North Slope oil fields. The spill came from a buried pipeline at a gravel production pad on the western side of the Kuparuk oil field. Kuparuk is the Slope's biggest oil field after Prudhoe Bay.
Dawn Patience, a spokeswoman for Conoco Phillips Alaska Inc., which runs Kuparuk, said the spill is estimated at 111,300 gallons of "produced water" covering about two acres. Produced water is water that's been separated from the mixture of crude oil and liquid natural gas that comes out of producing oil wells.
The leaky six-inch pipeline was carrying the produced water from a separating plant back to Kuparuk production pad 2H, where it was to be injected back into the ground to help maintain pressure in the oil field so that more oil can be produced.
The spilled water contains only a trace of crude oil, and the amount of actual oil spilled is believed to be slightly more than one barrel or about 50 gallons, Patience said. But much of the water is seawater, and the salt can kill tundra plant life just as crude oil can, said Leslie Pearson, spill prevention and emergency response manager for the Alaska Department of Environmental Conservation."
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