Whitefish dredging wraps up
A dredging project in Whitefish Lake to remove petroleum-laden sediment left by a 1989 train derailment has been completed ahead of schedule and in time to clear equipment away for the Fourth of July, one of the busiest days for watercraft traffic.
The U.S. Environmental Protection Agency said contractors for BNSF Railway Co. removed about 450 cubic yards of sludge from Mackinaw Bay, where a freight train derailed and spilled more than 20,000 gallons of diesel fuel into the pristine lake 23 years ago.
The dredging began May 21 and was conducted with federal oversight. Crews worked 12-hour days, six days a week making trips across the lake with a barge to transport the sludge into lined shipping containers staged in the City Beach area.
“The project team accomplished the objective and did so before the Fourth of July, as promised,” EPA On-scene Coordinator Steven Merritt said. “The dredging removed more than 97 percent of the petroleum contamination from Mackinaw Bay, eliminating the potential for sheen during summer recreational activity, and restored aquatic habitat for an important part of the Whitefish Lake ecosystem.”
The trace concentrations of diesel that remain are well below the stringent screening levels established by the EPA and the Montana Department of Environmental Quality for the project, making them unlikely to generate any visible sheen or inhibit aquatic life, Merritt said.
Residual contamination will break down over time as it’s consumed by naturally occurring bacteria and degraded by oxidation and sunlight, he added.
“All the heavy equipment and expensive GPS-guided dredging technology in the world cannot remove every last molecule of any spilled material without doing excessive damage to the environment,” he said. “Every removal, including this one in Mackinaw Bay, must take into account the net environmental benefit. Invariably, in cleanups involving petroleum hydrocarbons, the natural processes are the final step necessary to reduce these concentrations to zero.”
The last of the equipment necessary to support the removal, including the crane and the dredge, were removed from Whitefish Lake at City Beach late last week. All that remains is the washed river rock that served as the platform for the crane. That platform has been donated to the city of Whitefish by BNSF and will be converted by BNSF contractors into a launch ramp for the city’s rescue hovercraft once water levels recede.
Merritt said the project team, which included representatives from EPA, the U.S. Coast Guard, Montana Department of Environmental Quality, BNSF, KennedyJenks, and Envirocon, appreciated the cooperation from the Whitefish community, especially in the neighborhoods around City Beach.