Calumet County, WI: EPA's radon zone, explained

EPA places Calumet 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, Calumet County ranks higher in radon potential than 55% of rated counties (the 55th percentile).

Calumet County by the numbers

Calumet County, Wisconsin is home to about 53,602 people across 318.25 square miles. That works out to roughly 168 people per square mile. By population, Calumet County is the 335th largest of every county sharing its EPA zone — the 68th percentile by population within that zone. EPA's geology-based Region 5 groups Calumet County with 523 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

EPA's Zone 2 rating for Calumet County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Calumet County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

Next steps for a home in Calumet County

For a Calumet 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 Wisconsin's state radon program

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

Where Calumet County's figures come from

Calumet County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.