Exxon Mobil said that one of its pipelines leaked "a few thousand" barrels of Canadian heavy crude oil near Mayflower, Ark., prompting the evacuation of 22 homes and reinforcing concerns many critics have raised about the Keystone XL pipeline that is awaiting State Department approval.
The pipeline breach took place late Friday, Exxon said, in the 20-inch diameter, 95,000-barrel-a-day Pegasus pipeline, which originates in Patoka, Ill., and carries crude oil to the Texas Gulf Coast, the country's main refining center. Mayflower is about 25 miles north of Little Rock.
By Sunday afternoon, the company had deployed 15 vacuum trucks and 33 storage tanks to start cleaning up and temporarily store about 12,000 barrels of oil and water that had been recovered, the company said. Crews were steam-cleaning oil from property, Exxon Mobil said, while some fought in rainy weather to keep the oil from reaching nearby Lake Conway through storm drains.
The pipeline, which was built in the 1940s and was recently expanded, was carrying low-quality Wabasca Heavy crude oil from Alberta, Exxon Mobil spokesman Alan Jeffers said. According to the Crude Monitor website, Wabasca Heavy is a blend of oil produced in the Athabasca region, where the oil sands are located.
An existing Keystone pipeline carries crude oil that comes from the oil sands deposits in Alberta to Patoka though Exxon Mobil's Jeffers said he did not know if this batch of crude oil came from the Keystone line.
Many critics of the Keystone XL pipeline say that corrosion risks are greater in pipelines carrying low-quality bitumen-laden crude from the oil sands. They have urged President Barack Obama to reject the Keystone XL permit application.
TransCanada, owner of the Keystone system, has said that the new pipeline would be far safer than any other part of the nation's 2.6 million miles of oil, gas and chemical pipelines.
The Environmental Protection Agency declared the Arkansas leak a "major spill," a label put on any spill of 250 barrels or more. Exxon Mobil said it was preparing for a spill of up to 10,000 barrels, but that the estimate would probably end up being lower than that.