Is Oglala Lakota County, SD a radon risk area?

Oglala Lakota County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Nationally, Oglala Lakota County ranks higher in radon potential than 42% of rated counties (the 42nd percentile).

How Oglala Lakota County compares

About 13,360 people live in Oglala Lakota County, South Dakota, spread over 2,093.601 square miles. Population density there runs about 6 people per square mile. Rank 748 by population within its EPA zone puts Oglala Lakota County at the 28th percentile among zone peers. EPA's geology-based Region 8 groups Oglala Lakota County with 290 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

EPA's Zone 2 rating for Oglala Lakota County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Nothing about a Zone 2 label lowers the case for testing in Oglala Lakota County — EPA recommends it in every zone, moderate included.

Next steps for a home in Oglala Lakota County

Nothing about Oglala Lakota County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find South Dakota's state radon program

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

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.