LOUISVILLE, Ky. (WDRB) – A Marathon Petroleum Corp. pipeline in Shively leaked 160 barrels of jet fuel into the ground nearly two months ago, and only a small amount has been cleaned up, the company recently told federal regulators.

The quantity of fuel spilled Feb. 17 – more than 6,700 gallons -- is the most from a single incident in Kentucky since 2009, according to data from the U.S. Pipeline and Hazardous Materials Safety Administration.

Marathon has identified areas with contaminated soil and plans to begin excavations in late April or early May, said Tim Hubbard, assistant director of the Kentucky Division of Waste Management. The company must pay for the cost of the work, he said.

About three percent of the spilled fuel has been recovered, Marathon said in an initial report issued last month.

“We've seen some (spills) from pipelines that are a lot more than that -- a lot worse in terms of overall volume released,” Hubbard said. “But obviously anytime you have a release of that nature it is significant.”

Marathon suspects that the spill, in a pipe that carries jet fuel to Louisville International Airport, occurred after the line came into contact with an electric arc from an LG&E grounding rod.

“The cause of the incident is still under investigation, but it is believed that the leak was caused by an electrical arc from a grounding rod in the electric company's grounding system to (Marathon's) jet fuel pipeline, resulting in an electrical arc burn breach to the pipe and release of jet fuel,” Marathon wrote in its March 16 report.

LG&E spokeswoman Liz Pratt declined to respond directly to Marathon's claims.

“Because we weren't involved in developing the report, it would be inappropriate for us to comment on it or its initial findings,” Pratt said in an email.

But she acknowledged that LG&E had “an electric event that impacted one of our substations and created sparks around this same time in the area.”

She said the utility did safety and equipment checks in the area as it restored power but is not conducting any additional investigations.

According to Marathon's account, the leak occurred in an area behind a house on D-Lue Court in Shively. That house sits yards from a cluster of electrical transformers and on Tuesday afternoon had orange fencing lining the backyard.

Kenny Nauert, who lives two houses from the leak site, said he's not concerned about the jet fuel line. Most of his neighbors have known about the line for years, he said.

“This is the first incident there's with it,” he said.

The leak did not taint any drinking or groundwater, according to Marathon's report.

Marathon and the Shively Fire Department monitored nearby homes and sewer systems for gas vapors, officials said.

Shively Mayor Sherry Conner said Marathon notified her immediately after the leak and has provided regular updates. She said she wasn't aware of the scope of the spill until told by a reporter.

“I'm going to trust that they are going to monitor and do what they said and if there are any long-term effects on anything that they will take care of it,” she said.

Marathon spokeswoman Sid W. Barth said it's too early to describe the company's future monitoring plan but said it will be “fully vetted” by Kentucky environmental officials.

Barth said Marathon conducted in-line inspections of the pipe in 2014 and after this year's leak. In both cases, she said, the checks revealed no defects or signs of potential problems.

The pipeline moves jet fuel from Marathon's Algonquin Parkway terminal near the Ohio River to the UPS facility at the airport, Barth said. During the three days the line was out of service, Marathon shipped 100 truckloads of fuel per day to the airport, she said.

The February incident is the largest hazardous liquids spill in Jefferson County since an above-ground tank leaked more than 8,700 gallons of gasoline, diesel and jet fuel at a Chevron facility on Bells Lane in 2009, according to federal data. Chevron attributed the spill to operator error.

Federal regulators have labeled the Shively rupture a “significant” event -- one that kills or hospitalizes people, causes more than $50,000 in damage, releases 50 barrels or results in fire or explosion. Nationwide, 69 such incidents have happened this year.

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