Larimer County Landfill groundwater cleanup

Larimer County, the City of Loveland, and the City of Fort Collins are collaboratively working to address a groundwater contamination issue at the Larimer County Landfill.

Drinking water remains unaffected, and water supply wells around the vicinity of the landfill have not shown the presence of the contaminant through testing. 

The groundwater at the Larimer County Landfill has been shown to contain chlorinated volatile organic compounds [CVOCs] and other organic chemicals. One specific chemical, called 1,4- Dioxane, was first noted in 2016 and is the primary chemical of concern. 1,4-Dioxane is associated with some chlorinated solvents and is also a trace contaminant found in many cosmetics, detergents, and other household products.  The contaminated groundwater has migrated a limited distance off the landfill site onto the adjacent natural area.

Groundwater contamination has been an issue at the Larimer County Landfill since the early 1980s. The Larimer County Landfill is an old landfill and was built many years before the current environmental and solid waste regulations were enacted and technology existed to design with groundwater protection in mind.

For more than thirty years, Larimer County has monitored the potential for any contamination under the oversight of the Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment (CDPHE). Routine monitoring provides data necessary to characterize the nature and extent of the contamination. 

These efforts are now being extended cooperatively to identify, evaluate, and select a method to contain and clean up the source of this groundwater contamination on the landfill and the groundwater plume on the adjacent City of Fort Collins property.

Larimer County, with its consultant, TriHydro Corporation https://www.trihydro.com/, and the Cities of Fort Collins and Loveland are working on completing site testing that will lead to a design and implementation of a process focused on cleaning up contaminants in the groundwater. The City of Fort Collins is providing additional technical input through its consultant, AECOM, to assist in the effort.

The CDPHE will approve these corrective measures to ensure that the groundwater is cleaned to levels meeting public health and environment standards.

This corrective measure plan will be submitted to the State of Colorado, by a target date of Nov. 30, 2019. Larimer County and its municipal partners will begin implementing this plan after CDPHE approval and are committed to protecting public health and the environment.