Model remedies for mine sites
Cleaning up contamination from hardrock mine sites can be straightforward. Model remedies are pre-approved cleanups for common cleanup situations. Your site may qualify for a model remedy if it has:
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2,000 cubic yards or less of mine waste (soil, waste rock, or tailings)
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Soil contaminated with metals (no other suspected contaminants, and no impacted surface water, sediment, or groundwater)
Not all hardrock mining sites are contaminated. If you have a property with an abandoned mine, we may be able to help with sampling to determine if there are contamination concentrations above state cleanup levels.
Model remedies
You can choose from one of three model remedies or combine them. Details on each remedy are in our publication Model Remedies for Contaminated Mines Sites in Washington.
Excavation and removal
This remedy requires excavating all contaminated soil from your property and disposing of this soil at a certified landfill. If contamination extends deep into the soil, a large amount of soil must be excavated.
The benefit to excavation and disposal is that the remedy is permanent. No other actions are required once all contaminated soil is removed. It is often the most expensive option.
Capping in place
At this site in Okanogan County, mine waste was conslidated and capped, then covered with native plants.
Capping is a protective layer over contamination that prevents people, plants, or animals from being impacted by the contaminants. Capping requires the least amount of sampling because it's not important to know the specific concentrations of contaminants or how far down they extend. A properly-constructed cap will protect people and the environment from any of the contaminants found in mine waste piles.
Capping is often the least costly remedy, but it requires the greatest amount of long-term maintenance and monitoring. Institutional controls are required as part of this remedy.
Consolidation and capping
Consolidation and capping can be an excellent option for sites with multiple mine-waste piles. If your property has room to designate an area specifically for capped contamination, you can move contaminated soil from across the property to that area, then cap that area. The rest of the property would be clean and would not require any additional work.
This is a particularly effective remedy when there are numerous small waste-rock piles, and when large amounts of excavation are not required. Institutional controls are required as part of this remedy.
Cleaning up with a model remedy
If you clean up a site using an applicable model remedy, you may be able to get a free No Further Action letter through our Voluntary Cleanup Program. Contact the Voluntary Cleanup Program coordinator in your region for more information.
You do not have to complete a feasibility study if you use an appropriate model remedy.
Contact information
Justin Rice
Environmental Engineer, Contaminated Mine Sites
justin.rice@ecy.wa.gov
509-379-4967