EPA Superfund site
NEW IDRIA MERCURY MINE
Exposure status: insufficient data
Data limitations: Proximity to a Superfund site boundary does not mean your property is contaminated. EPA site boundaries show the area designated for cleanup, not the full extent of contamination. Groundwater plumes can extend beyond site boundaries. This tool shows publicly available EPA federal data. It is not affiliated with or endorsed by EPA, and is not a substitute for a professional environmental assessment.
About this site's exposure pathways
As of September 2023, the New Idria Mercury Mine Superfund site is considered “Insufficient Data to make a Human Exposure evaluation” (HEID). The New Idria Mercury Mine Superfund site was finalized on the NPL on 09/16/2011, and there has not yet been an evaluation of the human health exposure risks.
EPA uses this Human Exposure status when there is insufficient data/evidence to determine whether actual or reasonably anticipated human exposures are occurring, and/or whether those exposures are above acceptable risk-based levels. The planned activities to collect sufficient information to make a human exposure evaluation include the following: EPA is overseeing investigation work conducted by a potentially responsible party that is evaluating multiple media at the site, including water and soil. EPA is also overseeing the continued maintenance of a removal action to address uncontrolled flow of acid mine drainage. The potentially responsible party will submit a remedial investigation report that will include human health and ecological risk assessments.
EPA currently anticipates that there will be sufficient data to make a Human Exposure determination by 09/30/2026 because that is when EPA anticipates completing its review of the remedial investigation and risk assessments.