More than 20 years after a train derailed and spilled thousands of gallons of diesel fuel in Whitefish Lake, further clean up of the site is expected this month.

In 1989 a Burlington Northern freight train derailed and spilled more than 20,000 gallons of fuel into the Mackinaw Bay area on the northwest shore of the lake. Burlington Northern Santa Fe is planning to remove contaminated sediment from the area beginning the week of May 21.

The U.S. Environmental Protection Agency is overseeing the work.

The possibility of continued contamination was discovered in 2009.

Jennifer Chergo, with the EPA, noted that the Whitefish Lake Institute alerted the EPA to their testing of the lake, which showed contamination.

“BNSF did sampling and then got results back,” Chergo said. “Once they realized that they were going to be doing something they wanted to get in there before the summer season.”

Crews will begin to stage equipment at the City Beach boat ramp the week of May 14. The plan involves removing 400 cubic yards of petroleum-related contaminated sediment.

Sediment will be removed using an excavator on a barge. Curtains and booms will be used on the lake to prevent the spread of the contaminated soil. The sediment will be carried by boat to the City Beach boat ramp, loaded onto trucks and deposited at the BNSF facility. Sediment will be dried and then transported by railcar to a licensed facility in North Dakota.

The work is expected to last through June. During work, one of the boat ramps will be closed. The other ramp and City Beach will be open during the work.

“The goal is to be out of there before July — before it gets busy,” Chergo said. “There shouldn’t be too much impact.”

On July 31, 1989 a Burlington Northern train was traveling five miles north of Whitefish when a car turned sideways. The train piled up beside a hillside cut above Mackinaw Bay on Whitefish Lake. Four tank cars slid into the lake.

For several hours fuel poured out of one of the tank cars. Containment booms were placed on the lake. Gov. Stan Stephens declared a state of emergency in Flathead County. The beach and lake were closed to the public and lake clean up took place.

Then in 2009 a petroleum-tinted sheen was discovered in the lake. The Whitefish Lake Institute preceded to test the water and soil and found it to be 16.8 and 8.65 times higher than the maximum contaminant level, respectively.

The Institute alerted the EPA to its findings.