The Colorado Department of Public Health and Environment and the U.S. Environmental Protection Agency hosted several availability sessions and a public meeting for the Clear Creek Superfund Site. The virtual public meeting on August 3 at 6 p.m. included a formal presentation.

The goal of these meetings was to share information about an upcoming investigation into mine waste piles in the Clear Creek Superfund Site. The investigation is the first step in the cleanup process of these piles, which contain concentrated materials left over from mining operations in current or planned residential areas of the site. The investigation will occur within the 400 square-mile Clear Creek Watershed.

The Central City/Clear Creek Site consists of a 400 square-mile watershed extending from the Continental Divide east to near Golden, Colorado. The site is located in Gilpin and Clear Creek Counties.

The Hazardous Materials and Waste Management Division has contracted CDM Smith to investigate mine waste piles that have the potential to pose the greatest risk to human health. The agencies encourage residents to follow the best practices on the Operable Unit 5 factsheet to protect their health.

The Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment (CDPHE) recently established the Operable Unit 5 (OU5) for the Central City/Clear Creek Superfund Site. The purpose of OU5 is to evaluate potential exposures to heavy metals, primarily lead and arsenic, from mine waste piles in residential areas of the Site.

The discovery of gold near Idaho Springs, Central City, and Black Hawk in 1859 played a significant role in Colorado’s gold rush. For the next 20 years, the Black Hawk and Central City area was the leading mining center in Colorado, primarily due to the construction of mills to process the gold and silver mined nearby.

The silver crash in the 1890s led to a decline in area mining, but mining remained an important industry in Clear Creek and Gilpin counties until about 1950. Only a limited number of mines are currently in operation.

The site consists of multiple mine waste piles, tailings impoundments, and draining mines. Historic mining and milling activities resulted in the watershed becoming contaminated with heavy metals.

Several mine waste piles have been cleaned up, and two water treatment plants are operating in the Site to capture and treat mine-impacted water. Site investigations occur within the entire Clear Creek Watershed, which was designated as a Study Area.

Locations within the Study Area that are impacted by historic mining activities are considered part of the Superfund Site. The Agencies are currently working to define the formal Site boundary. Due to the evolving science on lead and the increased residential development in areas of the Study Area, the EPA and CDPHE designated OU5 to investigate the nature and extent of contamination that exists in mine waste piles in residential areas of the Study Area.

EPA placed the site on the Superfund program’s National Priorities List (NPL) in September 1983. The Agencies are currently conducting a Remedial Investigation/Feasibility Study for OU5.

Risks associated and healthy home best practices include washing hands, pets and children’s toys. Keep the dirt outside.

If you live near a waste pile, create a safe space for children to play. Wash the veggies. Lead is a primary concern.

The agencies will continue community involvement and have developed a fact sheet. For questions, email Shannon. Bauman@state.co.uc or Google CDHE Clear Creek.