What EPA's radon map says about Union County

EPA's own radon map rates Union County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Union County sits at the 35th percentile nationally for radon potential — above 35 of every 100 rated counties.

How Union County compares

About 3,926 people live in Union County, New Mexico, spread over 3,825.05 square miles. Averaged across its land area, Union County runs about 1 people per square mile. Among counties sharing Union County's EPA zone, it outranks 7% of them by population. Geologically, Union County is grouped into EPA Region 6 alongside 502 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Union County's Zone 2 prediction lands in the gap between the two. Middle-of-the-pack doesn't mean risk-free for any one Union County address — a moderate county average still leaves individual homes to test either side of it.

Testing and mitigation in Union County

Mitigation cost doesn't depend on Union 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 New Mexico's state radon program

Union County's test kit answers today; a Airthings radon monitor keeps answering for Union 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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone Union County carries, the zone explainer covers what it does and doesn't tell you about any one house.