Cold weather speeds fuel cleanup efforts
Ali Bronsdon, Leader Staff
Fuel spill cleanup efforts along Highway 35 are ramping up in anticipation of winter weather.
On April 2, a Keller Transport truck overturned on Highway 35 approximately 500 feet from Flathead Lake and spilled nearly 6,500 gallons of gasoline, contaminating soil and groundwater between the highway and the lake.
An updated Phase I plan of action, recently released by the United States Environmental Protection Agency and contracted clean-up firm Environmental Partners, Inc. of Issaquah, Wash., is available at the Polson City Library.
The plan includes excavation and replacement of contaminated soils, installation of a groundwater collection trench, installation of air abatement systems in each of the affected homes and installation of groundwater monitoring systems to confirm the effectiveness of the trenching system at capturing impacted groundwater.
Preparation for excavation started last week with the cutting down of trees before building a permanent groundwater treatment system. Before replacing the excavated areas with fresh soil, crews will install a trench that will continue to collect contaminated stream water and send it to the treatment system. Spring water from three naturally occurring springs showed contamination.
“It is currently being treated through a temporary water treatment system, which has to be replaced before it snows because it is near the lake shore and will freeze when it gets too cold,” said Donna Inman with the EPA in Denver, Co.
This week, crews started the excavation of the more highly contaminated soil areas.
According to Inman, the contaminated soil is not a “characteristic hazardous waste,” so the excavated contaminated soil will be disposed of at a licensed landfill near Missoula. The work plan on file at the library calls for the installation of two groundwater collections trenches, but the current plan received by EPA this week has only the lower trench being installed - a decision based on site conditions changing with the passage of time, Inman said.
Additionally, an air abatement system (air treatment ventilation system) is currently being installed under one of the five houses between the highway and the lake that were impacted by the spill. The homes were found to have high levels of Volatile Organic Compound (VOC) vapors and were evacuated. The remaining four homes will have air abatement systems installed over the next two months. Depending on how the houses have been constructed, if there is not a crawl space in their basement the floor must be ripped up to install a series of pipes under the house. A positive pressure pulls the contaminated air into the pipes and evacuates it, via a vent, to the outside of the house.
“Those systems will be removing the vapors so the people can move back in,” said Inman who admits a number of factors will contribute to that timeline. For example, the size of the house and how contaminated the soil is under the house.
Officials will test for contamination approximately 30 days after the system is installed and running.
Once those tests come back safe, and after a thorough cleaning of all carpets, curtains and upholstry that were exposed to vapors in the six months since the spill, the homeowners may return to their homes.Ali Bronsdon
Leader Staff
Fuel spill clean-up efforts along Highway 35 are ramping up in anticipation of winter weather.
On April 2, a Keller Transport truck overturned on Highway 35 approximately 500 feet from Flathead Lake and spilled nearly 6,500 gallons of gasoline, contaminating soil and groundwater between the highway and the lake.
An updated Phase I plan of action, recently released by the United States Environmental Protection Agency and contracted clean-up firm Environmental Partners Inc. of Issaquah, Wash. is available at the Polson City Library.
The plan includes excavation and replacement of contaminated soils, instillation of a groundwater collection trench, instillation of air abatement systems in each of the affected homes and instillation of groundwater monitoring systems to confirm the effectiveness of the trenching system at capturing impacted groundwater.
Preparation for excavation started last week with the cutting down of trees before starting to build a permanent groundwater treatment system. Before replacing the excavated areas with fresh soil, crews will install a trench that will continue to collect contaminated stream water and send it to the treatment system. Spring water from three naturally occurring springs showed contamination.
“It is currently being treated through a temporary water treatment system, which has to be replaced before it snows because it is near the lake shore and will freeze when it gets too cold,” Donna Inman with the EPA in Denver, Co. said.
This week, crews started the excavation of the more highly contaminated soil areas.
According to Inman, the contaminated soil is not a “characteristic hazardous waste,” so the excavated contaminated soil will be disposed of at a licensed landfill near Missoula. The work plan on file at the library calls for the installation of two groundwater collections trenches, but the current plan received by EPA this week has only the lower trench being installed - a decision based on site conditions changing with the passage of time, said Inman.
Additionally, an air abatement system (air treatment ventilation system) is currently being installed under one of the five houses between the highway and the lake that were impacted by the spill. The homes were found to have high levels of Volatile Organic Compound (VOC) vapors and were evacuated. The remaining four homes will have air abatement systems installed over the next two months. Depending on how the houses have been constructed, if there is not a crawl space in their basement the floor must be ripped up to install a series of pipes under the house. A positive pressure pulls the contaminated air into the pipes and evacuates it, via a vent, to the outside of the house.
“Those systems will be removing the vapors so the people can move back in,” said Inman who admits a number of factors will contribute to that timeline. For example, the size of the house and how contaminated the soil is under the house.
Officials will test for contamination approximately 30 days after the system is installed and running.
Once those tests come back safe, and after a thorough cleaning of all carpets, curtains and upholstry that were exposed to vapors in the six months since the spill, the homeowners may return to their homes.