Columbia County, AR radon potential

Columbia County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally that's the 14th percentile for radon potential — Columbia County outranks 14% of every county EPA has rated.

How Columbia County compares

Columbia County, Arkansas is home to about 22,024 people across 766.065 square miles. That works out to roughly 29 people per square mile. Within its own EPA zone, Columbia County is bigger by population than 44% of the counties that share it. Geologically, Columbia County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

Zone vs. an actual test

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Columbia County's Zone 3 prediction is the low end of the scale. Even at Zone 3, Columbia County homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

If Columbia County tests above the action level

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 Columbia County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Columbia 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 Columbia 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 Columbia County carries, the zone explainer covers what it does and doesn't tell you about any one house.