What EPA's radon map says about Lancaster County

Lancaster County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Rank it against the rest of the country and Lancaster County lands in the 98th percentile for radon potential.

Where Lancaster County sits nationally

About 332,857 people live in Lancaster County, Nebraska, spread over 837.56 square miles. Averaged across its land area, Lancaster County runs about 397 people per square mile. Among counties sharing Lancaster County's EPA zone, it outranks 94% of them by population. EPA's geology-based Region 7 groups Lancaster County with 411 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Lancaster County's predicted average sits above EPA's own action level of 4 pCi/L — the concentration at which EPA recommends fixing a home — versus a national average around 1.3 pCi/L indoors and 0.4 pCi/L outdoors. Some Lancaster County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Testing and mitigation in Lancaster County

Mitigation cost doesn't depend on Lancaster 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 Nebraska's state radon program

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

Lancaster County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.