Billings, MT-based Keller Transportation, a trucking company responsible for a 2008 tanker spill near the shore of Flathead Lake in western Montana that cost more than $1 million to clean up, has been ordered to pay a $83,500 fine by the U.S. Environmental Protection Agency.

A tractor-trailer owned by Keller ran off the road and overturned on April 2, 2008, spilling 6,300 gallons of gasoline into springs along Flathead Lake, impacting groundwater as well as Flathead Lake near Finley Point in Lake County, within the boundary of the Flathead Indian Reservation, according to a news report posted by the Daily Inter Lake.

The accident was caused by excessive speed around a curve on Montana Route 35, which caused the tanker-trailer to strike a rock embankment and rupture, according to the EPA.

Fumes from the spill forced the evacuation of five homes along the lake for nearly a year.

Keller agreed to pay the fine to settle Clean Water Act claims and violations of the Oil Pollution Act that prohibit the discharge of oil into U.S. waters. Its liability insurance coverage paid out the maximum $1 million to clean up the spill, and a second insurance company covered additional costs.

“This penalty serves as a strong reminder that every effort must be taken to avoid accidents and spills when hauling hazardous materials,” EPA Enforcement Director Mike Gaydosh said in a press release.