Boulder Valley Frequency

In the shadow of the mine: Life near Colorado’s most contaminated site

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0:00 | 17:25


July 10, 2026

Colorado's largest Superfund site by area stretches 400 square miles across Gilpin and Clear Creek counties, just north of Boulder County. The site has been in remediation for nearly five decades, and a new scope of remediation is assessing the health risk of lead left behind by historic mining to residents.

At Gilpin County's recent annual health fair, public health workers were testing residents' blood for lead. On today's episode, we sat down with Gilpin's Public Health director Alisa Witt to find out the risks this poses to county residents. 

Check out a map of Colorado's Superfund sites here
Did you know? Boulder County is home to 3 Superfund sites

Contact Gilpin County Public Health at 303-582-5803 to schedule free blood lead testing, or for more information on soil and well water testing.

More on Superfund budget + accelerated cleanups under the Trump administration: sciencefriday.com/articles/epa-accelerates-superfund-site-cleanup/