What EPA's radon map says about Duchesne County

Duchesne County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Rank it against the rest of the country and Duchesne County lands in the 82nd percentile for radon potential.

Where Duchesne County sits nationally

About 20,803 people live in Duchesne County, Utah, spread over 3,235.523 square miles. Averaged across its land area, Duchesne County runs about 6 people per square mile. Among counties sharing Duchesne County's EPA zone, it outranks 47% of them by population. EPA's geology-based Region 8 groups Duchesne County with 290 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Duchesne County carries a Zone 1 label because its predicted average clears 4 pCi/L outright — three-plus times the 0.4 pCi/L typical outdoors and above the 1.3 pCi/L most homes see. A Zone 1 rating means testing is worth doing sooner rather than later, but it is still county-wide average, not a reading for any single house — some homes in Duchesne County will test well under the action level, and EPA's guidance is to test regardless of zone.

Next steps for a home in Duchesne County

Mitigation cost doesn't depend on Duchesne County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Utah's state radon program

Duchesne County's test kit answers today; a Airthings radon monitor keeps answering for Duchesne County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

More on how this number was built

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.