Scott County, MO: EPA's radon zone, explained

EPA's own radon map rates Scott County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally that's the 20th percentile for radon potential — Scott County outranks 20% of every county EPA has rated.

Where Scott County sits nationally

Scott County, Missouri is home to about 37,957 people across 420.006 square miles. Averaged across its land area, Scott County runs about 90 people per square mile. By population, Scott County is the 420th largest of every county sharing its EPA zone — the 59th percentile by population within that zone. EPA's geology-based Region 7 groups Scott County with 411 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Scott County

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Scott County's Zone 3 prediction is the low end of the scale. A Zone 3 label describes Scott County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Next steps for a home in Scott County

For a Scott 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 Missouri's state radon program

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

Where Scott County's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.