EPA Superfund Site
BUNKER HILL MINING & METALLURGICAL COMPLEX
ID | EPA ID IDD048340921
About this site’s exposure pathways:
As of September 2023, the Bunker Hill Superfund site’s measure of risks to people’s health is “Human Exposure Not Under Control.” This is due to several reasons, chief among them being people that recreate in areas of the site that have not yet been cleaned up (i.e., stream and riverbeds and banks, lake shorelines) or cleaned up but barriers to deeper contamination have been breached (i.e., riding All-Terrain-Vehicles [ATVs] on hillsides or mine dumps). People recreating in these areas can be exposed to lead, arsenic, and other heavy metals in soil, dust, and sediment which can then be brought home with them.
Since the site was listed on the National Priorities List in 1983, the top priority has been to reduce people’s exposures to mining-related contaminants in soil, dust, sediment, and drinking water. Populated areas where people live, work, go to school, and play sports were often built upon mining wastes generated from nearby mining, milling, and smelting operations and were the first to be targeted for cleanup primarily through removal of contaminated soil and capping with clean materials. In communities within the site’s original 21-square mile boundary called the Bunker Hill “Box” (aka Operable Units 1 and 2), a total of 3,236 properties have been cleaned up and 17 contaminated residential drinking water wells have been closed. Only nine properties in the Box remain to be cleaned up once owners grant access. In communities outside of the Box, called the Coeur d’Alene “Basin” (aka Operable Unit 3), a total of 3,935 properties have been cleaned up and of the seven homes that were initially provided under-sink water filtration systems, six remain and are maintained at no cost to the property owner. Another 36 properties in the Basin require cleanup based on sampling results and another 202 properties require sampling, but in both cases, owners have either refused or have not responded to multiple requests for access.
Although most populated areas have been cleaned up, continuing to reduce or limit people’s exposures to mining-related contamination in these areas continues to be a top priority. Approaches to reduce or limit exposures, especially to lead and arsenic in soil and dust, include maintaining a list of Box and Basin “refusal” properties in case current owners change their minds or there is a change in ownership: providing free training and assistance for and oversight of property owners, contractors, and developers as part of the site’s Institutional Controls Program should homes or businesses be remodeled or vacant land be developed to ensure clean barriers to underlying contamination are maintained or established per local land-use restrictions tied to the site’s cleanup goals; offering free year-round blood lead screening to residents as part of the site’s Lead Health Intervention Program which includes an annual, week-long blood screening event where a cash incentive is offered to families with children between the ages of 6 and 6-years and a free in-home assessment of possible lead sources should blood-lead results exceed 3.5 micrograms per deciliter; and, sampling and analyses of lead in house dust as part of the site’s Basin Property Remediation and House Dust Monitoring programs followed by a free in-home assessment to ascertain possible lead sources should sampling results exceed house dust goals. Approaches to reduce or limit exposures to contaminated drinking water continue to include installation and maintenance of water filtration systems, and closing of contaminated drinking water wells.