Willacy County, TX: EPA's radon zone, explained

EPA's own radon map rates Willacy County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Rank it against the rest of the country and Willacy County lands in the 13th percentile for radon potential.

How Willacy County compares

Willacy County, Texas is home to about 20,027 people across 590.613 square miles. That works out to roughly 34 people per square mile. By population, Willacy County is the 618th largest of every county sharing its EPA zone — the 40th percentile by population within that zone. Willacy County falls in EPA Radon Region 6, one of 503 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

Willacy 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. Even at Zone 3, Willacy County homes are not guaranteed a low reading — zone is a county-wide average, and EPA recommends testing every home regardless of zone.

If Willacy County tests above the action level

For a Willacy County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Texas's state radon program

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

Where Willacy 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. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.