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On August 1, 2015 mechanical damage to a diesel dispenser caused the filter housing to leak into the under dispenser container (UDC), releasing an estimated 50 gallons of diesel fuel into the nearby storm drain. The release was reported to the state immediately. The release made its way through the series of storm drain conduit to the north side of I-70 when a resident observed and reported the fuel where it had exited into an open storm ditch.
While Seneca Fuel Systems made the repairs to the damaged dispenser, Seneca Environmental Services responded to the call and met with state and local officials, including the fire department, police department, DOT, public works and others. The path of the release was documented and was found to have flowed into a subgrade storm culvert that was blocked by mud on one end in a marshy area where the fuel became trapped, keeping it from reaching a lake further downstream.
A game plan was formulated by Seneca Environmental Services to clean up the released fuel and the pathway it ran. Permits and property access were secured from Colorado DOT and landowners, respectively. Seneca Waste Solutions vacuum trucks and technicians were mobilized right away. The vacuum trucks recovered a majority of the 50 gallons of diesel from the drainage ditches and the culvert.
The marshy area where the fuel had settled was excavated, and the impacted soil was profiled and disposed of at a nearby landfill. The storm ditches were excavated and the soil was disposed, and the storm drain manways and conduits were flushed with biodegradable detergents and rinsed with power washers while vacuum trucks recovered all wash water.
Sensitive cattail areas downstream were not notably impacted by the release, and were sprayed with Micro Blaze, a biodegradable hydrocarbon mitigation agent which uses natural microbes, to degrade the remaining residual petroleum contaminants over time.
Soil samples were collected from various locations within the excavated drainage ditches along the spill path, and surface water samples were collected from various locations along downstream. All samples resulted in concentrations below any state corrective action levels. A report summarizing all activities and sampling results was submitted to the state and No Further Action was granted November 10, 2015. All local and state agencies involved were notified of the results and copied on the report and NFA letter from the state.
This project included facets from three Seneca Companies divisions working together to provide “The Complete Solution” to what could have become a major environmental problem.