What EPA's radon map says about McKenzie County

McKenzie County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. That puts McKenzie County in the 79th percentile nationally for radon potential — higher than 79% of the counties EPA has rated.

Where McKenzie County sits nationally

About 14,782 people live in McKenzie County, North Dakota, spread over 2,760.133 square miles. Averaged across its land area, McKenzie County runs about 5 people per square mile. Among counties sharing McKenzie County's EPA zone, it outranks 38% of them by population. Geologically, McKenzie County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

Zone vs. an actual test

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line McKenzie County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. 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 McKenzie County will test well under the action level, and EPA's guidance is to test regardless of zone.

Testing and mitigation in McKenzie County

Mitigation cost doesn't depend on McKenzie 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 North Dakota's state radon program

McKenzie County's test kit answers today; a Airthings radon monitor keeps answering for McKenzie 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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone McKenzie County carries, the zone explainer covers what it does and doesn't tell you about any one house.