Illinois Gulch Site

The Illinois Gulch Site is an area of historic mining activity along Boreas Pass Road in Breckenridge, Colorado.

Water from historic adits and natural seeps drain through several large mine waste piles at the Site. This contaminated water, characterized by elevated levels of heavy metals and low-pH, works its way down the watershed to Illinois Gulch, the Blue River and ultimately Dillon Reservoir.

The Site is located in a residential area and several properties along Brooks Hill Drive are immediately adjacent to the historic mine features. EPA has not determined whether or not these properties have been impacted by mine waste but investigations will be performed in Summer 2021.

 EPA issued an Order to the owner of the historic mine features, TransAmerica, to perform the following tasks:

a) reduce the flow of water from the adits by preventing water from entering a nearby mine shaft;

b) control the flow of water through the wetland and move it away from the waste piles;

c) install a passive remediation system to improve water quality;

d) consolidate and cap the waste piles; and

e) sample nearby residential properties and remediate them as necessary.

The following are the current activities being conducted for the October 30, 2021 to November 8, 2021:

• Completed the sealing of stop log brackets to the outlet structure.
• Installed a closure gate at the access road entrance.
• Completed the demobilization of equipment from the Site.

Work is completed for the season at the Illinois Gulch Site. Monitoring and maintenance activities and development of a water treatment plan will begin in Spring of 2022.  

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More information can be found on the EPA website. Please click the button below to connect to the EPA website.