What EPA's radon map says about Vigo County

Vigo County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Vigo County sits at the 60th percentile nationally for radon potential — above 60 of every 100 rated counties.

Vigo County by the numbers

About 106,166 people live in Vigo County, Indiana, spread over 403.631 square miles. That works out to roughly 263 people per square mile. Among counties sharing Vigo County's EPA zone, it outranks 82% of them by population. Geologically, Vigo County is grouped into EPA Region 5 alongside 523 other counties that share its rock and soil setting.

What this actually means for a house in Vigo County

EPA's Zone 2 rating for Vigo County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Middle-of-the-pack doesn't mean risk-free for any one Vigo County address — a moderate county average still leaves individual homes to test either side of it.

Testing and mitigation in Vigo County

Mitigation cost doesn't depend on Vigo 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 Indiana's state radon program

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

The methodology guide shows exactly which EPA and Census sources feed Vigo County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.