What EPA's radon map says about Park County

Park County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Park County sits at the 85th percentile nationally for radon potential — above 85 of every 100 rated counties.

Where Park County sits nationally

About 31,082 people live in Park County, Wyoming, spread over 6,939.039 square miles. That works out to roughly 4 people per square mile. Among counties sharing Park County's EPA zone, it outranks 57% of them by population. Geologically, Park County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

What this actually means for a house in Park County

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Park County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. Some Park County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Next steps for a home in Park County

Mitigation cost doesn't depend on Park 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 Wyoming's state radon program

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

More on how this number was built

Park County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Park County carries, the zone explainer covers what it does and doesn't tell you about any one house.