Protecting Public Health and the Environment.

Preliminary Assessment Program for Mined Lands and Industrial Facilities

In February 2002, DEQ initiated a Preliminary Assessment and Site Inspection Program to evaluate and prioritize assessment of potentially contaminated sites. Idaho has more than 8,500 inactive and abandoned mines, mineral locations, and mineral discoveries. The state also has multiple abandoned or repurposed industrial facilities such as old landfills, repair and maintenance shops, dry cleaners and laundromats, rural airfields, railroad depots, and various manufacturers. Due to accessibility and funding considerations, priority is given to sites where potential contamination poses the most substantial threat to human health or the environment.

The Preliminary Assessment Program is implemented through a cooperative agreement between DEQ and EPA.

Remediation Options

The vast majority of sites assessed by DEQ do not warrant remedial action based on current uses. In the cases where DEQ finds that a substantial risk exists, one of several actions may occur.

  • The current owner or responsible party may voluntarily act to abate or manage risks at the property, although no formal agreement to do so is entered into with the government.
  • If there is a responsible party who is willing to work with DEQ to manage or abate associated risks, the property owner may enter DEQ’s Voluntary Cleanup Program and implement corrective action.
  • If a public entity is willing to take ownership of the site and either abate or manage risks at the site, the property may be a candidate for DEQ's Brownfields Program.
  • None of the property owners who have participated in the program are cleaning up sites due to regulatory action by DEQ; however, DEQ does have the regulatory obligation to address environmental threats and may instigate an administrative action by issuing the responsible party (owner/operator) a Notice of Violation (NOV) consistent with the Hazardous Waste Management Act (HWMA) or Environmental Protection and Health Act (EPHA). After issuing an NOV, DEQ will seek to alleviate the existing threat and may pursue penalties for violations of state law and cost recovery.
  • In the event that no responsible party exists and there is an imminent and substantial threat to human health and/or the environment, DEQ's director may declare a state of emergency. This declaration would allow DEQ to use emergency response funding to hire remediation specialists to clean up the site. Emergency response funds are drawn from penalties imposed on responsible parties who have violated the HWMA.
  • If state funding is unavailable, or the site falls under federal jurisdiction, the site may be placed on EPA National Priority List. EPA then leads the site cleanup effort.

Contact Us

If you would like to find out whether a site in your area poses a possible threat, or provide DEQ with information about a site that you suspect is contaminated, contact your nearest DEQ regional office or the staff contact listed on this web page.

Completed Preliminary Assessments by County

DEQ prepares preliminary assessment and site inspection reports of mine and industrial sites. DEQ's work at the sites listed below is in various stages of progress ranging from looking to acquire legal access to completiing preliminary assessment or site inspection report. Some of the sites listed below may also have links to engineering plans or construction completion reports for remedial action at the site.  Final preliminary assessment or site inspection reports are usually completed by DEQ within 5 to 6 months after a site visit has been conducted.

Note: Listed sites are private properties. Do not enter without the owner's permission. If authorized, avoid contact with hazardous materials and respect the property's historical significance.

Records 31 to 40 of 304
Site NameCountyAssessment TypeAssessment DateDocument Links
Big Buffalo Mine
(aka Alligator Mine, Merrimac Mine, Alligator, Merrimac, Thistle, Ajax #2, Texas, Trilby, Maremack Fraction, Buffalo Bull, Oro Fino Wedge, Oro Fino, Buffalo Hump Fraction, Merrimack, Molly Gibson, Clara B, Pirate, Red Cross, Improvement Lode & Mill Site, Hattie B)
IdahoMiningFebruary 2011Preliminary Assessment and Site Inspection Report
Big Wood River
BlaineMiningJune 2015Supplemental Site Inspection Report

2010 Site Inspection Report
Bimetallic Ridge Mines
(aka Catherine Mine [aka Silver Butte Mine], Brown Bear Mine [aka Silver Butte Mine, Silver Hill, Erickson], Hope and Faith Shaft, Iron Mask Mine)
BonnerMiningJanuary 2013Preliminary Assessment and Site Inspection Report

Addendum to Preliminary Assessment and Site Inspection Report
Black Horse, Hillside, and Big Bonanza Mines
(aka Black Horse, Hillside, and Big Bonanza patented mining claims)
BlaineMiningDecember 2007Preliminary Assessment Report
Black Spar Mine
(aka Silver Spar Mine; aka Black Spar, True Blue, USA, Black Spar Fraction, White Spar, Edna M. Fraction, Sunnyside, Good Hope, Siler Wedge, Geneva, Lost Ben Ross, Little Joe, Moonlight, Dorothy I, Bogard, May, Silver Tip, Little Wonder, Great Northern, and Lucky Boy patented mining claims)
BlaineMiningOctober 2008Preliminary Assessment Report
Bloomington Canyon Mine
Bear LakeMiningOctober 2007Preliminary Assessment Report

Preliminary Assessment Report Addendum
Blue Gulch
(aka Dewey Mine, Empire Mine, Blue Gulch Mine, Black Jack-Trade Dollar Mine, Dewey Tunnel, Idaho Tunnel, No. 12 Adit, Empire State Tunnel, Humboldt Mine, Summit Mine, Brunzel Mine, Trade Dollar Consolidated Mill, Alta Vista Mine, and Idaho Mine; aka Rough and Ready, Gordan, Seventy-nine, Phillips, Palm Beach Inn, Caliph of Bagdad, Independence, Economy, Industry, Blaine, Blaine Extension, Colorado, Jumbo, Black Bart, Pluto, South Pluto, Caroline, Fraction, Empire State, Phillip, and Alta Vista patented mining claims)
OwyheeMiningDecember 2004Preliminary Assessment Report

Dewey Tunnel Blue Gulch Phase 1A Site Characterization and Screening Risk Analysis

Dewey Mine Site Inspection

Expanded Site Inspection Jordan Creek Historic Mining Area
Boulder Basin Claims
(aka Boulder Group Mines: aka Sunset, Climax, Calamine, Mascot, Revenue, Triumph, Summit, Daisy, Mint, Champion, Trapper, Tip Top, Sullivan, Puritan, Crown Point patented mining claims; Golden Glow Mines: aka Louisa, Bazouk, Ohio, Ophir, Sunrise patented mining claims)
BlaineMiningDecember 2008Preliminary Assessment Report
Buckskin Mine
(aka Buckskin East, Early Bird)
CusterMiningOctober 2015Preliminary Assessment and Site Inspection
Buffalo Hump Mining District
(aka Robbins Mining District, Vesuvius Mine, Alhambra Mine, Spokane Mine, Tiger Prospect, Altoona Mine, Big Buffalo Mine, Cracker Jack Mine [aka Cracker Jack Mill], Winslow Prospect, Wiseboy Mine, North Star Mine, Lucky Lad Mine, Mother Lode Mine [aka Concord], Ajax Mine, Atlas Mine and Mill, Rob Roy Mine [aka Dice Mine], St. Louis Mine, Jumbo Mine and Mill [aka Brooklyn Mill] and Jumbo Camp, Del Rio Mine and Mill [aka Venture], Dewey Occurrence, Sheep Creek Placers, and miscellaneous patented mine and mill site claims)
IdahoMiningFebruary 2011Preliminary Assessment and Site Inspection Report

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Staff Contacts

Assessment and Compliance Bureau Chief
Dean Ehlert
DEQ State Office
Waste Management & Remediation Division
1410 N. Hilton
Boise, ID 83706
(208) 373-0416

DEQ Guidance

Gilmore Townsite Health and Safety Fact Sheet

Related Mining Reports

Related Pages

Brownfields in Idaho

Voluntary Cleanup Program