Grant County, MN radon potential

Grant 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 Grant County in the 72nd percentile nationally for radon potential — higher than 72% of the counties EPA has rated.

Grant County by the numbers

Grant County, Minnesota is home to about 6,109 people across 547.8 square miles. Population density there runs about 11 people per square mile. Within its own EPA zone, Grant County is bigger by population than 18% of the counties that share it. EPA's geology-based Region 5 groups Grant County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Grant 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 Grant 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 Grant County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Minnesota's state radon program

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

Where Grant County's figures come from

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