What EPA's radon map says about Delta County

EPA places Delta 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. Delta County sits at the 3rd percentile nationally for radon potential — above 3 of every 100 rated counties.

How Delta County compares

About 5,647 people live in Delta County, Texas, spread over 256.832 square miles. That works out to roughly 22 people per square mile. Among counties sharing Delta County's EPA zone, it outranks 10% of them by population. EPA's geology-based Region 6 groups Delta County with 502 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Delta County's Zone 3 prediction is the low end of the scale. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Delta County testing above the action level often enough that skipping a test isn't the safe assumption.

Next steps for a home in Delta County

Mitigation cost doesn't depend on Delta 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

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

More on how this number was built

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.