Colorado · Dolores County

Radon Levels in Dolores County, Colorado

In Dolores County, Colorado, 47.1% of pre-mitigation home radon tests came back at or above the EPA action level of 4 pCi/L — based on 34 tests collected by the Colorado Department of Public Health and Environment between 2005 and 2024. The county’s median pre-mitigation reading was 3.8 pCi/L, with a maximum recorded result of 80.6 pCi/L.

EPA recommends mitigation when long-term indoor radon measures at or above 4 pCi/L. Counties with elevated medians and large test counts — like Dolores — typically warrant testing during real-estate transactions and seasonal retesting in occupied homes.

Dolores County by the numbers

Source: Colorado Department of Public Health and Environment. Pre-mitigation indoor radon tests, 2005–2024.

Tests above 4 pCi/L
47.1%

EPA action level

Total tests recorded
34

CDPHE 2005–2024

Median result
3.8 pCi/L

pre-mitigation

Maximum recorded
80.6 pCi/L

outlier high

How Dolores compares to Colorado as a whole

Both bars show the percentage of pre-mitigation tests that came back at or above the EPA action level of 4 pCi/L.

Dolores County47.1%
Colorado statewide46.9%

CDPHE 2005–2024

Dolores County tests 0.2 percentage points higher than the statewide average.

Service note

We don’t service Dolores County directly.

Colorado Radon Check operates along the Front Range. For radon mitigation in Dolores County, we recommend finding a NRPP-certified mitigator near you — that credential is your best signal of a competent, accountable contractor.

Find an NRPP-certified pro

Filter by “Certified Mitigation Specialist” to see radon mitigation companies in Dolores County.

NRPP (the National Radon Proficiency Program) certifies measurement and mitigation professionals nationally. Colorado also issues state licenses for radon mitigators — ask your pro for both.

Free download

But the free Colorado Radon Risk Map still applies.

All 64 counties on one page — built from CDPHE’s 214,362 pre-mitigation tests. See where Dolores County ranks and what your neighbors are seeing.

No spam. Just the map and the occasional Colorado-radon update.

Dolores County radon questions

What level of radon is dangerous?
The EPA recommends mitigation at 4 pCi/L or higher. Between 2 and 4 pCi/L, you should consider mitigation — long-term exposure at this range still carries lung-cancer risk. Below 2 pCi/L, the EPA suggests retesting every two years.
How much does radon mitigation cost in Colorado?
A standard sub-slab depressurization system in Colorado typically runs $1,200–$2,500, with $1,500 the most common all-in price. That single system reduces indoor radon by 95% or more in the majority of homes. Crawlspace installs cost more ($2,000–$5,000) because the membrane and tie-ins are more involved.
Why are radon levels elevated in Dolores County?
Geology drives most of it. Granitic bedrock and uranium-bearing soils — common across Colorado — release radon as they decay, and Front Range building style (basements, tight envelopes, forced-air systems) concentrates that gas indoors. Higher-elevation counties also tend to have lower atmospheric pressure, which can pull radon up through the foundation more aggressively.