What EPA's radon map says about Lake County

EPA's own radon map rates Lake County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Rank it against the rest of the country and Lake County lands in the 64th percentile for radon potential.

Where Lake County sits nationally

About 502,955 people live in Lake County, Indiana, spread over 498.884 square miles. Population density there runs about 1,008 people per square mile. Among counties sharing Lake County's EPA zone, it outranks 95% of them by population. EPA's geology-based Region 5 groups Lake County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Lake County's Zone 2 prediction. A county-wide moderate average, like Lake County's, can still hide a specific house well above or below it — testing is what actually answers the question.

Next steps for a home in Lake County

Mitigation cost doesn't depend on Lake 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

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

More on how this number was built

Lake 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.