Now that crews have repaired a leak on the Keystone pipeline, they’re working to clean up the ground contaminated by crude oil. TransCanada shut down the pipeline last week when a local landowner discovered a leak. The company is now pumping oil through the line at reduced pressure.
TransCanada officials are investigating what caused 16,800 gallons of oil to escape the Keystone pipeline and saturate the ground near Freeman. A federal regulator oversees that analysis.
State officials are ensuring the company properly removes dirty soil. Workers excavated 350 feet of dirt along the line to isolate the problem spot.
Brian Walsh is an environmental scientist with South Dakota’s Department of Environment and Natural Resources. He says TransCanada needs to take dirt from the bottom and sides of the site for testing.
"They collect samples from what’s left in the excavation to ensure that that is clean material and that they have removed all of the contaminated material," Walsh says.
The samples go to a lab, and DENR gets the results.
"If for some reason we didn’t feel they had enough samples to properly characterize the area or if they exceeded any of our requirements or action levels for additional excavation, we would direct TransCanada to perhaps continue excavating or do whatever they need to do to make sure we had the entire area cleaned up before it was backfilled and they moved on," Walsh says.
Walsh says the department also ensures crews backfill the site with clean soil that isn’t contaminated from this spill or another area.
Mark Cooper with TransCanada says the company is committed to returning the land to the way it was before the oil leak. He says that includes restoring the earth and replacing any vegetation crews had to remove to find the leak and repair the line.