What EPA's radon map says about Ellsworth County

EPA's own radon map rates Ellsworth County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. Ellsworth County sits at the 72nd percentile nationally for radon potential — above 72 of every 100 rated counties.

Where Ellsworth County sits nationally

About 6,316 people live in Ellsworth County, Kansas, spread over 715.575 square miles. Population density there runs about 9 people per square mile. Among counties sharing Ellsworth County's EPA zone, it outranks 18% of them by population. EPA's geology-based Region 7 groups Ellsworth County with 411 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Ellsworth County's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Ellsworth County specifically.

If Ellsworth County tests above the action level

Mitigation cost doesn't depend on Ellsworth 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 Kansas's state radon program

Ellsworth County's test kit answers today; a Airthings radon monitor keeps answering for Ellsworth 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. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.