Polk County, AR radon potential
EPA places Polk 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 13th percentile for radon potential — Polk County outranks 13% of every county EPA has rated.
Where Polk County sits nationally
Polk County, Arkansas is home to about 19,434 people across 856.838 square miles. Population density there runs about 23 people per square mile. Within its own EPA zone, Polk County is bigger by population than 39% of the counties that share it. Polk County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.
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, Polk County's Zone 3 prediction is the low end of the scale. A Zone 3 rating means Polk County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.
If Polk 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 Polk County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Polk 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 Polk 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. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.