Superfund Site Profile

Clean up activities are ongoing at the site. Remedies that have been completed are currently protective of human health and the environment. Where remedies are not complete, access is controlled to prevent human exposure to waste.

Recent updates:

You will need Adobe Reader to view some of the files on this page. See EPA’s PDF page to learn more.

  • June 2017 – EPA issued a proposed plan (PDF) (11 pp, 1.5 MB) to amend the Anaconda Regional Water, Waste and Soils operable unit Record of Decision (PDF) (825 pp, 175 MB) for the surface water remedy EPA and Montana Department of Environmental Quality are proposing:
    • A limited waiver of the State of Montana’s acute and chronic water quality criteria for specific stream reaches and their tributaries. A 2017 Surface Water Technical Impracticability Evaluation Report (PDF) (914 pp, 127 MB) confirmed that achieving State of Montana standards would likely be impossible to carry out.
    • Additional upland remediation where practicable.
  • May 2017 – EPA signed an Explanation of Significant Differences (PDF) (7 pp, 3.8 MB) that describes two recent changes to the remedy for the community soils operable unit:
    • Continue to address primary sources of interior dust contamination through sampling and cleanup and promote a comprehensive health and education program.
    • Remove arsenic contaminated soils in gardens to a maximum depth of 24 inches and 12 inches for other areas of a residential yard.
  • 2017 – Atlantic Richfield, a potentially responsible party at the site, started to clean up over 450 of the residential yards in Anaconda that were sampled in 2016. Atlantic Richfield will continue to sample and clean up yards as needed over the next few years. A fact sheet (PDF) (4 pp, 3 MB) is available that provides an update about the community soils remedy.
  • EPA completed the fifth five-year review (PDF) (255 pp, 66.6 MB) of the site in 2015. A 2017 Project Update fact sheet (PDF) (8 pp, 6.3 MB) summarizes the work conducted since the last review.


The 300-square-mile Anaconda Co. Smelter site is located at the southern end of the Deer Lodge Valley in Montana, at and near the location of the former Anaconda Copper Mining Company (ACM) ore processing facilities. ACM facility operations included removal of copper from ore mined in Butte from about 1884 through 1980. Milling and smelting produced wastes with high concentrations of arsenic, as well as copper, cadmium, lead and zinc. These wastes contaminated soil, groundwater and surface water with hazardous chemicals. Cleanup is complete at several areas within the site. At these areas, operation and maintenance activities are ongoing. Cleanup is underway at the remaining areas.