CAVE CREEK LANDFILL REMEDIATION PROJECT

Background

Cave Creek Landfill (CCL) began operations around 1965 in the area known as the “Old Landfill.” Somewhere around 1984, operations shifted to the “New Landfill.” The CCL stopped accepting waste in 1998. (A transfer station continues to operate, but all waste is hauled offsite.) As was typical with landfills operated at those times, liners were not required. The CCL was permitted to accept residential and commercial municipal solid waste and other wastes including: appliances, barnyard and stable waste, demolition material, non-infectious medical waste, domestic animals (large and small), green waste, foods, and inert materials. 

As required by law in 1993, the County installed two down gradient groundwater monitoring wells (south and southeast of the landfill) and began to monitor these wells along with an already existing up gradient well (north of the landfill). Each well is located on County property. In December 1997, trichloroethene (TCE) above the Aquifer Water Quality Standard of 5.0 micrograms per liter (ug/L) was found in the monitoring wells. Maricopa County entered into a Consent Order with the Arizona Department of Environmental Quality (ADEQ) which assigns the responsibility for site remediation to the County. ADEQ approved a Remedial Action Plan (RAP) and continues to approve periodic revisions to the plan.

The groundwater contamination from CCL is over 600 feet below the ground surface and does not impact any drinking water sources or any other known sources of water use. Remediation is ongoing and will continue until complete to the satisfaction of ADEQ.