What EPA's radon map says about Vernon County

EPA places Vernon County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally, Vernon County ranks higher in radon potential than 46% of rated counties (the 46th percentile).

Where Vernon County sits nationally

About 19,787 people live in Vernon County, Missouri, spread over 826.391 square miles. That works out to roughly 24 people per square mile. Among counties sharing Vernon County's EPA zone, it outranks 39% of them by population. Geologically, Vernon County is grouped into EPA Region 7 alongside 411 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Vernon County's Zone 2 prediction lands in the gap between the two. Vernon County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

Testing and mitigation in Vernon County

Mitigation cost doesn't depend on Vernon 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 Missouri's state radon program

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

The methodology guide shows exactly which EPA and Census sources feed Vernon County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.