Grant County, AR radon potential

EPA places Grant County in Zone 3 - Low Potential — a predicted county-wide average indoor radon level below 2 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 12th percentile for radon potential — Grant County outranks 12% of every county EPA has rated.

How Grant County compares

Grant County, Arkansas is home to about 18,546 people across 631.888 square miles. That works out to roughly 29 people per square mile. Within its own EPA zone, Grant County is bigger by population than 37% of the counties that share it. Grant County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Grant 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. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Grant County testing above the action level often enough that skipping a test isn't the safe assumption.

Testing and mitigation 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 Arkansas'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. RADONZONE-10OFF at checkout knocks 10% off.

Where Grant County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Grant County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.