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St. Vrain River Mystery Spill

Site Contact:
Joyce Ackerman
Federal On-Scene Coordinator


Site Location:
Longmont, CO 80501
NRC#: 1328602

On February 9, 2022,  Longmont Fire Department and Boulder County Hazmat received a report of a hydrocarbon sheen and product in a storm water drain.  The hydrocarbons flowed for several hours into the drainage and a pond in a community park.  Longmont Fire Department and Boulder County Hazmat deployed booms and were able to contain the spill before it entered the St. Vrain River.  The hydrocarbons are suspected to be diesel or gasoline.  Boulder County Hazmat requested EPA assistance in the response.

The hydrocarbon product was found in a pond in Kensington Park, a popular community park.  The pond and park are adjacent to The Slough which drains into the St. Vrain River, a navigable water. 

On February 10, 2022, EPA deployed an On-Scene Coordinator (OSC) to Longmont, CO. After conducting an initial assessment with the Longmont Fire Department and Boulder County Hazmat, EPA added additional booms and sorbent materials to the drainage path. Some hydrocarbon sheen is still present on the surface of the pond, but is not recoverable due to the small quantities of petroleum present and the shallowness of the pond. 

EPA will continue to check on the sorbent materials and coordinate with local stakeholders. 

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