One month after a pipeline rupture sent 210,000 gal of heavy crude oil through an Arkansas neighborhood, officials announced initiation of a “reentry plan” so residents can start returning to their homes.
That return will be “over the next few weeks,” according to a statement from the city-county-EPA-ExxonMobil command headquarters in Mayflower, Ark., near Little Rock.
“We are working with the construction crews and local Unified Command now to try to finalize the details around dates/times for these questions, but we don’t have that just yet,” Russ Roberts, ExxonMobil spokesman, says in response to questions about when homes would be available for occupancy and the neighborhood cleaned up.
The cause of the 22-ft gash in the Pegasus pipeline on March 29 is still under investigation. The 90,000-barrel-a-day pipeline carries diluted bitumen crude, or dilbit, from Patoka, Ill., to Nederland, Texas.
Meanwhile, the pipeline had a second, smaller breach near Doniphan, Mo., about 200 miles north of Mayflower. ExxonMobil said it was notified April 30 and that about one barrel, or 42 gal, leaked. The repair was completed May 3, but the pipeline remains shut down.
That breach is also being investigated. A preliminary investigation indicates the breach is related to action by an unspecified third party, Roberts says. The pipeline is marked.
However, Renee Bungart, Missouri Dept. of Natural Resources spokeswoman, says, “Upon excavation, Exxon has determined the release occurred from the installation of a guide wire used to support a powerline pole … located almost directly on top of the pipeline.”
In Mayflower, the 53-ft section of the pipeline that was removed has been sent to Hurst Metallurgical Research Laboratory Inc. in Euless, Texas, for testing.
One pipeline safety expert who has seen photos of the gash blames welding practices used in the 1940s, when the 850-mile-long pipeline was constructed.
“It looks like this is a seam-related weld failure,” says Richard Kuprewicz, president of Accufacts Inc. in Redmond, Wash. “They show up in pipe manufactured in the early ‘70s or earlier.”
However, he cautions, detailed metallurgical tests will have to be performed to determine the cause.
In Kalamazoo, Mich., where a pipeline break dumped more than 1 million gal of a similar heavy crude into the Kalamazoo River in July 2010, the EPA is making pipeline owner Enbridge Inc. return this summer to dredge three sites where large deposits of oil sludge still remain.
The areas are near Ceresco Dam, the Mill Ponds impoundment near Battle Creek and the Morrow Lake delta.
The new cleanup will cost an estimated $175 million, says Enbridge spokesman Jason Manshum. The company has spent $820 million on cleanup and related costs.