Koochiching County, MN: EPA's radon zone, explained

EPA places Koochiching County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 41st percentile for radon potential — Koochiching County outranks 41% of every county EPA has rated.

Koochiching County by the numbers

Koochiching County, Minnesota is home to about 11,594 people across 3,104.706 square miles. That works out to roughly 4 people per square mile. By population, Koochiching County is the 792nd largest of every county sharing its EPA zone — the 23rd percentile by population within that zone. Koochiching County falls in EPA Radon Region 5, one of 524 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Koochiching County's Zone 2 prediction. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Koochiching County — testing is the only way to know an individual home's actual level.

Next steps for a home in Koochiching County

For a Koochiching 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 Minnesota's state radon program

For Koochiching County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Koochiching 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 Koochiching County's figures come from

Koochiching County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.