Open House
The Griggs Walnut Ground Water Plume Superfund Open House will take place from 10 a.m. to 2 p.m. on Thursday, September 18, 2025 at 153 N. Cottonwood St., near the intersection of Griggs Avenue and Walnut Street.
What is a Superfund?
The City of Las Cruces, Dona Ana County and the Environmental Protection Agency are actively working to clean up a contaminated area in Las Cruces.
A superfund is a federal hazardous-substances remediation program created by the EPA in 1980.
Perchloroethylene (PCE) is a chemical used in dry cleaning and degreasing. In 1993 a plume of dissolved PCE, nearly 1.8 miles long and half mile wide, was detected underground, between 190 and 650 feet below the surface.
To protect the public, four city wells were shut down after the discovery. In 2012, two of those wells were reactivated to pump water into the new treatment facility. One well retired in July 2024, the remaining well continues to support treatment operations.
Treatment takes place with up to 500 gallons per minute. It consists of air stripping and disinfecting. Contaminated groundwater is pumped into the facility where it enters two air strippers. Machines diffuse air through the water causing the PCE to evaporate and separate from the water. After PCE is removed, the water is disinfected and sent to the Upper Griggs Reservoir. Right now, about half of the original 300 pounds of PCE have been removed. The remaining contamination is expected to be fully eliminated by 2032.
In 2020, the EPA, the City and County, the U.S. Department of Defense and the National Guard Bureau entered into a consent decree under which the federal government agreed to pay almost $7.25 million for the remediation.
The City and County paid about $6.5 million each for the construction of the treatment facility and continued operation. The City and County pay the EPA about $90,000 a year for oversight.
Get More information on the Griggs and Walnut Ground Water Plume Superfund: https://www.donaanacounty.org/departments/administration/legal-risk-department/superfund-site
