Edmunds County, SD radon potential

EPA's own radon map rates Edmunds County zone 1 - highest potential, predicting a county-wide average indoor level above 4 pCi/L. That puts Edmunds County in the 70th percentile nationally for radon potential — higher than 70% of the counties EPA has rated.

Edmunds County by the numbers

Edmunds County, South Dakota is home to about 4,027 people across 1,125.98 square miles. Averaged across its land area, Edmunds County runs about 4 people per square mile. Within its own EPA zone, Edmunds County is bigger by population than 11% of the counties that share it. Geologically, Edmunds County is grouped into EPA Region 8 alongside 290 other counties that share its rock and soil setting.

Zone vs. an actual test

Edmunds County carries a Zone 1 label because its predicted average clears 4 pCi/L outright — three-plus times the 0.4 pCi/L typical outdoors and above the 1.3 pCi/L most homes see. Some Edmunds County homes will test comfortably under the action level despite the county's Zone 1 rating — the only way to know which kind of home you have is an actual test.

Next steps for a home in Edmunds County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find South Dakota's state radon program

For Edmunds County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Edmunds 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 Edmunds County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Edmunds County's numbers. Whatever zone Edmunds County carries, the zone explainer covers what it does and doesn't tell you about any one house.