Is Wallowa County, OR a radon risk area?

Wallowa County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. That puts Wallowa County in the 4th percentile nationally for radon potential — higher than 4% of the counties EPA has rated.

Wallowa County by the numbers

About 7,522 people live in Wallowa County, Oregon, spread over 3,145.897 square miles. That works out to roughly 2 people per square mile. Rank 892 by population within its EPA zone puts Wallowa County at the 13th percentile among zone peers. EPA's geology-based Region 10 groups Wallowa County with 141 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Wallowa County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. Even at Zone 3, Wallowa County homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

Testing and mitigation in Wallowa County

Nothing about Wallowa County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Oregon's state radon program

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

More on how this number was built

Wallowa County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.