ADAIR VILLAGE, Ore. (AP) – A massive fuel spill on an Oregon highway that has caused traffic detours and delays for the past 10 days is now looking even worse after wildlife managers discovered fuel contamination has spread into the groundwater.

A massive fuel spill contaminated groundwater in Adair Village, Oregon, forcing more than 9000 tons of soil to be excavated, July 18, 2017 (DEQ)

The Statesman Journal reports E.E. Wilson Wildlife Area managers found out about the contamination on Monday.

Department of Environmental Quality spokeswoman Katherine Benenati says contamination also has spread to Coffin Butte Landfill on the other side of Highway 99W.

Oregon Petroleum Transport is on the hook for the cost of environmental cleanup and for rebuilding an 800-foot (240-meter) stretch of the highway.

The spill happened when one of the company’s double-tanker trucks crashed into a ditch with a load of about 11,000 gallons (41,600 liters) of gasoline and diesel.

Officials with DEQ told KOIN 6 News a total of 9020 tons of petroleum-contaminated soil was excavated west of the original highway surface for disposal at Coffin Butte Landfill.

More excavation continues beneath Highway 99 and in the EE Wilson Wildlife area east of the bypass. There is about 5 to 6 feet of clean soil above the contamination, officials said.

Because the contamination is so deep, there hasn’t been any observed impact on wildlife at this time. Groundwater monitoring wells will be installed in the wildlife area and at the landfill.KOIN 6 News contributed to this report.

A massive fuel spill contaminated groundwater in Adair Village, Oregon, forcing more than 9000 tons of soil to be excavated, July 18, 2017 (DEQ)