Official Government Website
Estimated Abandoned Mines and Prospects in Idaho

Thousands of mines have closed in Idaho since gold was discovered in the Boise Basin in 1862. Most of these abandonments occurred long before responsible mine reclamation policies became the norm. 

The Abandoned Mine Reclamation Act was adopted by the Idaho Legislature in 1994. The Idaho Department of Lands, on behalf of the Land Board, administers the Act to reclaim lands affected by past mining activities in Idaho. The Act defines an abandoned mine as one that is “deserted by the operator, having no regular maintenance, and not covered by a valid mining claim.” 

One-third of the Idaho Mine License Tax is deposited into the Abandoned Mine Land Reclamation Fund. The remainder of the Mine License Tax is currently deposited into the General Fund.

Money from the Abandoned Mine Land Reclamation Fund may be spent on the reclamation of any eligible mining operation

Learn Why and How Idaho's Abandoned Mine Program Started

Role of the Land Board

The State Board of Land Commissioners is charged with administering Idaho’s Abandoned Mine Reclamation Act. On behalf of the Land Board, Idaho Department of Lands implements the provisions of the Act.

Under the Act, the Land Board is responsible for:

  • Reclaiming abandoned surface, placer and underground mines, including milling and processing areas.
  • Sealing deep mine entries.
  • Revegetating affected land to prevent erosion and sedimentation.
  • Preventing, abating, treating and controlling water pollution created by abandoned mine drainage.
  • Controlling surface subsidence due to underground mines.
  • Contracting with vendors and dispersing grants to conduct and promote research, surveys or training needed to carry out the provisions of the Act.
  • Prioritizing public health and safety over the restoration of land and water resources.
  • Coordinating with other state and federal agencies.
  • Reasonably compensating other agencies.

Public Safety is the Top Priority

IDL’s Abandoned Mine Lands (AML) program promotes public safety by identifying dangerous conditions at mines that are no longer operating and by securing dangerous orphaned mine openings. IDL has worked cooperatively with the Bureau of Land Management, the United States Forest Service, and the Idaho Department of Fish and Game to close dozens of mine openings. IDL has also assisted numerous private landowners by closing mine openings on their land.

We use information provided by the Idaho Geologic Survey to help identify and find dangerous mines that require closure.

Participation is Voluntary

The Act is written such that it is a voluntary program for reclaiming abandoned mines. An eligible mining operation is an abandoned mine on state or federal land, or an abandoned mine on private land when the owner of the land has requested (and the Land Board has granted) designation as an eligible mine.

As a result, the Act does NOT:

  • Authorize trespassing without landowner consent
  • Require compensation by Potentially Responsible Parties (PRPs)

Protecting History, Endangered Species

The Land Board strives to address historic preservation concerns. If a site is older than fifty years, the Board will try to avoid impacts to the historical integrity of the site. If avoidance is not possible, then mitigation may be needed. 

The Board also works to address endangered species concerns. Remediation efforts on a site are generally designed to accommodate bat habit (bat-friendly gates).

How We Close Abandoned Mines

Methods used to close abandoned mines are site specific. Wildlife habitat, mine location and structure, and cost analysis all determining factors.

When wildlife habitat is not a concern, we close abandoned mines using alluvial deposits available on the site (dirt and rock), or with rigid polyurethane foam that is mixed and sprayed into the opening. 

When our local area staff has the time, expertise, and equipment needed to close an abandoned mine we use their services because this is the most cost effective way to close the opening to an abandoned mine. At other times we’ll use local contractors. While safety is the top priority, keeping costs low is a close second.

It typically costs between $2,000 and $20,000 per site to close abandoned mines. Often there are multiple pits or portals on a site to be reclaimed.

Additional Resources

Minerals Leasing

Mined Land Reclamation

Dredge and Placer Mining


Idaho Geologic Survey

BLM AML Program


Resource Protection and Assistance Bureau

Eric Wilson, Bureau Chief
Regulatory Minerals Program
(208) 334-0261

IDL Supervisory Areas

For questions specific to a location, please contact the nearest Supervisory Area.

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