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Kuparuk field had 95,000-gallon water spill; corrosion cited
Elizabeth Bluemink Anchorage Daily News
Corrosion led to the biggest oily water spill in years at the Kuparuk oil field on Christmas Day, state records show.
Conoco Phillips, which runs the North Slope oil field, estimated the size of last month’s spill — containing salty water and a trace amount of crude oil — at 94,920 gallons. The hot liquid sprayed out of a 3-inch crack in a water injection line at a Kuparuk well.
The last time that the 6-inch line had been inspected for corrosion was in 2000 and no problems were detected at that time, said Natalie Lowman, a Conoco spokeswoman. Kuparuk’s pipeline network encompasses about 800 miles.
The December spill contaminated nearly three acres of snow-covered tundra with a light misting of oily water, and it also contaminated nearly two acres of gravel at the well pad, according to a state spill report. The cleanup, about 95 percent complete, involved removing the contaminated gravel and snow, recycling the oily water and snowmelt and putting the rest of the contaminated material in waste dumps, according to the state’s spill report.
No production shutdown The leak didn’t cause a shutdown in oil production, Lowman said.
Corrosion is a big issue at North Slope oil fields. Corrosion in transit lines at the Prudhoe Bay oil fields caused a couple of serious pipeline spills and shutdowns in 2006 that led to federal criminal penalties against BP, which runs Prudhoe Bay.
After the 2006 spills at Prudhoe, Conoco stepped up its own corrosion detection program at Kuparuk, the slope’s second-largest oil field. In 2006, the company told regulators it had found 12 bad spots at the oil field. That year, a corrosion-caused hole in a Kuparuk line spilled about 500 gallons of oil and water.
Twice in the past year, corrosion has been detected at Kuparuk, state regulators said Jan. 12.
The most recent Kuparuk spill happened in December 2007: Roughly 4,284 gallons of oil, gas and water leaked from a pressurized line due to external corrosion. That leak forced the shutdown of 8 percent of Kuparuk’s average output, ConocoPhillips officials said at the time.
Since 2004, Conoco has reported five spills at Kuparuk, according to state records.
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