Radon levels in ZIP 56738

ModerateEPA Zone 1

ZIP 56738 (Marshall County, Minnesota): predicted long-term basement average of 3.2 pCi/L (model estimate), about 1.5× the average US ZIP (2.2) and about 1.3× the Minnesota average (2.4). This is the most populous ZIP in Marshall County.

Test ZIP 56738 - the EPA says "consider fixing" in this range

The predicted basement average here is 3.2 pCi/L, in the 2-4 pCi/L band where the EPA recommends considering mitigation. Plenty of individual homes in a moderate area test above 4. Start with a short-term test; if it comes back at 2 or higher, follow up with a long-term test or a continuous monitor.

Already tested at 4 pCi/L or higher? Find a certified mitigation professional (EPA). A mitigation system typically runs $800-$2,500 installed.

We may earn a commission from Amazon at no extra cost to you.

Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.

3.2 ± 0.06

pCi/L predicted basement mean (model SD)

1.9 ± 0.07

pCi/L predicted upstairs mean

2.9 ± 0.06

pCi/L predicted typical screening test

How 56738 compares

Within Marshall County, ZIP 56738 ranks #6 of 9 ZIPs by predicted basement level; the county average is 3.3 pCi/L and its ZIPs run from 2.1 to 3.7. The county is EPA Radon Zone 1. About 1,368 people lived in this ZIP at the 2010 Census.

Above-ground floors are predicted at 1.9 pCi/L, below the action level, while basements sit in the 2-4 band. If you spend time in a finished basement, test there first.

Other ZIP codes in Marshall County

ZIP 56738 radon questions

Is radon high in ZIP 56738?
Moderate. The model's predicted long-term basement average for ZIP 56738 is 3.2 pCi/L (SD 0.06), with above-ground floors at 1.9 pCi/L. That is about 1.5× the average US ZIP code (2.2) and close to the Marshall County average of 3.3. It ranks 6 of 9 ZIPs in the county.
Do I need to test my home in 56738?
Yes. 56738's predicted average falls in the EPA's 2-4 pCi/L "consider fixing" band, and a meaningful share of individual homes in such areas test above 4. Test with a short-term kit and confirm anything at 2 or higher with a long-term test.
What EPA radon zone is ZIP 56738 in?
ZIP 56738 lies mostly in Marshall County, which the EPA classifies as Radon Zone 1 (highest potential (predicted average > 4 pCi/L)). Zones are county-wide and date from 1993; the ZIP-level prediction above is from a 2001-2021 model built on millions of tests.

ZIP pages are generated for ZIPs predicted at or above 2.5 pCi/L and for the most populous ZIP in each county; all other ZIPs appear in their county table. Methodology.