EPA Superfund Site

KAISER ALUMINUM (MEAD WORKS)

WA | EPA ID WAD000065508

About this site’s exposure pathways: As of June 2025, the Kaiser Mead (Aluminum Works) Superfund Site is considered “Insufficient Data to Determine Human Exposure Control” (HEID). Offsite groundwater is a direct contact (ingestion) risk to current and future residents because fluoride and cyanide (free) are higher than their drinking water maximum contaminant levels (MCLs) of 4 ug/L and 200 ug/L, respectively, in a sole-source aquifer. The groundwater plume discharges to surface water at one or more locations in the Spokane River, approximately 2.5 miles from the property, at concentrations that are higher than their cleanup standards (960 ug/L for fluoride based on MTCA B and 5.2 ug/L for cyanide (free) based on chronic water quality criteria). The plume is not delineated and the current pump and treat system is not functioning as intended. Washington Department of Ecology is the lead agency for the site and EPA is currently working towards an agreement to initiate a supplemental remedial investigation and focused feasibility study later this year. EPA anticipates that sufficient data to make a Human Exposure determination will be available by May 2028, following the completion of these planned investigations.