What EPA's radon map says about Polk County

Polk County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Polk County sits at the 23rd percentile nationally for radon potential — above 23 of every 100 rated counties.

Where Polk County sits nationally

About 54,258 people live in Polk County, Texas, spread over 1,057.053 square miles. Averaged across its land area, Polk County runs about 51 people per square mile. Among counties sharing Polk County's EPA zone, it outranks 69% of them by population. EPA's geology-based Region 6 groups Polk County with 502 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Polk County

A Zone 3 county like Polk County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. A Zone 3 label describes Polk County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Testing and mitigation in Polk County

Mitigation cost doesn't depend on Polk County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Texas's state radon program

Polk County's test kit answers today; a Airthings radon monitor keeps answering for Polk County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

More on how this number was built

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