Cheyenne County, KS: EPA's radon zone, explained

EPA's own radon map rates Cheyenne County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Cheyenne County sits at the 68th percentile nationally for radon potential — above 68 of every 100 rated counties.

Cheyenne County by the numbers

Cheyenne County, Kansas is home to about 2,646 people across 1,019.89 square miles. Averaged across its land area, Cheyenne County runs about 3 people per square mile. By population, Cheyenne County is the 996th largest of every county sharing its EPA zone — the 6th percentile by population within that zone. Geologically, Cheyenne County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Cheyenne County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. That doesn't mean every Cheyenne County house tests high — a zone is a county-wide prediction, never a single-home reading — but it's a reason to test sooner rather than let it wait.

Next steps for a home in Cheyenne County

For a Cheyenne County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Kansas's state radon program

For Cheyenne County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Cheyenne County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

Where Cheyenne County's figures come from

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