Lincoln County, WY: EPA's radon zone, explained

EPA places Lincoln County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 82nd percentile for radon potential — Lincoln County outranks 82% of every county EPA has rated.

How Lincoln County compares

Lincoln County, Wyoming is home to about 21,000 people across 4,075.337 square miles. Averaged across its land area, Lincoln County runs about 5 people per square mile. By population, Lincoln County is the 559th largest of every county sharing its EPA zone — the 48th percentile by population within that zone. Geologically, Lincoln County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

What this actually means for a house in Lincoln County

Lincoln 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 Lincoln 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 Lincoln County

For a Lincoln 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 Wyoming's state radon program

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

Where Lincoln County's figures come from

Lincoln County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.