LITTLE ROCK, Ark. (AP) -- Arkansas' attorney general on Tuesday asked ExxonMobil to preserve records pending a state investigation into a crude oil spill that, while small, has generated broader questions about the safety of cross-country pipelines.
Clean-up crews have recovered about 12,000 barrels of crude oil and water since a leak on Friday soiled a neighborhood in Mayflower, about 25 miles northwest of Little Rock, and almost threatened nearby Lake Conway.
"There are many questions and concerns remaining as to the long-term impacts, environmental or otherwise, from this spill," Arkansas Attorney General Dustin McDaniel wrote to ExxonMobil executives Tuesday while launching a probe into the leak's cause and impact. The company said it will cooperate.
Investigators were still working to determine what caused the spill, which led authorities to evacuate nearly two dozen homes.
"It's obvious that the rupture was not the fault of the state and the state has been damaged in addition to the private property owners," McDaniel told reporters Tuesday.
The Arkansas spill comes days after a train carrying crude from Canada derailed last week in western Minnesota, leaking thousands of gallons of oil onto the frozen ground.
While the Minnesota spill appeared to be under control from an ecological standpoint, it stood to play a role in the politics surrounding the Keystone XL pipeline, which would transport oil from tar sands in Canada to refineries in Texas.
Environmentalists have criticized the Keystone XL proposal, though a recent State Department report seemed to knock down one of their arguments by saying that when it comes to global warming, shipping the oil by pipeline would release less pollution than using rail.
Still, some environmentalists pointed to the recent Arkansas spill to highlight their concerns about the Keystone XL pipeline.
"It's not a question of whether pipelines leak. It's when," said Michael Brune, executive director of the Sierra Club.
A spokesman for TransCanada, the Keystone pipeline builder, said the environmentalists' arguments aren't so much about a particular pipeline as they are about a larger campaign to end the use of fossil fuels.
"The problem with that is you can't sit there and lead the public to believe that if one pipeline isn't approved ... that suddenly the demand for fossil fuels stops," TransCanada's Shawn Howard said. "Every day, each of us consumes fossil fuels. I don't care if you're an environmental activist or you're somebody who works in the oil industry."
President Barack Obama is considering whether to approve Keystone XL after Calgary-based TransCanada changed the project's route though Nebraska.
The Obama administration blocked the project last year because of concerns that the original route would have jeopardized environmentally sensitive land in the Sand Hills region. The administration later approved a southern section of the pipeline, from Cushing, Okla., to the Texas coast.
The pipeline that ruptured in Arkansas dates back to the 1940s, according to ExxonMobil, and is part of the Pegasus pipeline that carries crude oil from the Midwest to refineries in the Gulf of Mexico.
Karen Lewis, who lives just outside Mayflower, expressed concerns about the age of the pipeline and whether there could be more leaks in the future.
"This is exactly what the environmentalists and people against Keystone have been yacking about," she said.
Associated Press writer Andrew DeMillo contributed to this report.
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