Is radon high in Grant County, Minnesota?

Moderate. The model predicts a long-term basement average of 3.4 pCi/L in Grant County (about 1.9× the US average of 1.8 and about 1.4× the Minnesota average of 2.4). That is in the 2-4 pCi/L range where the EPA recommends considering mitigation. Ranked 30 of 87 Minnesota counties.

Should I test for radon in Grant County?

Yes, soon. With a predicted average of 3.4 pCi/L, many homes in Grant County will test above the 4 pCi/L action level. Use a short-term kit first; if it reads 2 or higher, confirm with a long-term test or continuous monitor before deciding on mitigation.

What does EPA Radon Zone 1 mean for Grant County?

Zone 1 - highest potential (predicted average > 4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 3.4 pCi/L does not line up with Zone 1, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.

How much does radon mitigation cost in Grant County?

A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Minnesota quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

Radon levels in Grant County, Minnesota

ModerateEPA Zone 1

Predicted long-term basement average of 3.4 pCi/L (model estimate) across 7 ZIP codes - about 1.9× the US average of 1.8, about 1.4× the Minnesota average of 2.4. Ranked #30 of 87 Minnesota counties.

Test Grant County, MN - the EPA says "consider fixing" in this range

The predicted basement average here is 3.4 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.

Get a short-term test kit →Or track it with 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.

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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. Measured Minnesota test results are shown separately and labeled as such. How the numbers work.

3.4 ± 0.06

pCi/L predicted basement mean (model SD)

2.1 ± 0.07

pCi/L predicted upstairs (above-ground) mean

3.1-3.6

range of ZIP-level basement predictions in the county

Measured tests in Grant County (Minnesota Dept. of Health, 2016-2025)

Actual results from voluntary home tests, separate from the model above. Measured averages usually run higher than the model because tests skew toward basements and worried homeowners.

Mean: 6.6 pCi/L
Median: 5.7 pCi/L
Tests ≥ 4 pCi/L: 66.7%
Tests per year: 12

Source: MN Public Health Data Access.

What this means for Grant

The typical Grant County home is predicted in the 2-4 pCi/L band. The EPA's guidance for this range is to consider fixing, because there is no known safe level and roughly one home in several in a moderate area will test above 4.

Note that the EPA classifies Grant County as Zone 1 while the newer model predicts 3.4 pCi/L. The zone map predates two decades of test data; where they disagree, we grade on the model but show both. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable Minnesota counties: Steele County (3.4), Houston County (3.3), Dodge County (3.3), Clay County (3.5). The state's highest is Rock County at 4.7 pCi/L.

ZIP codes in Grant County

Predicted basement and upstairs means by ZIP (model estimate). ZIPs whose land is mostly in this county.

ZIP	Basement	Upstairs	Grade
56531	3.6 ± 0.07	2.1	Moderate
56309	3.3 ± 0.06	2.0	Moderate
56339	3.1 ± 0.06	2.0	Moderate
56248	3.4 ± 0.05	2.1	Moderate
56311	3.2 ± 0.06	2.0	Moderate
56590	3.4 ± 0.07	2.1	Moderate
56274	3.3 ± 0.06	2.0	Moderate

If your test comes back at 4 pCi/L or higher

Mitigation is a routine job: a fan-driven pipe that vents soil gas from under the slab to above the roofline, typically $800-$2,500 installed (typical range; local quotes vary). Use certified professionals: EPA find-a-professional. Read the full mitigation guide.

Grant County radon questions

Is radon high in Grant County, Minnesota?: Moderate. The model predicts a long-term basement average of 3.4 pCi/L in Grant County (about 1.9× the US average of 1.8 and about 1.4× the Minnesota average of 2.4). That is in the 2-4 pCi/L range where the EPA recommends considering mitigation. Ranked 30 of 87 Minnesota counties.
Should I test for radon in Grant County?: Yes, soon. With a predicted average of 3.4 pCi/L, many homes in Grant County will test above the 4 pCi/L action level. Use a short-term kit first; if it reads 2 or higher, confirm with a long-term test or continuous monitor before deciding on mitigation.
What does EPA Radon Zone 1 mean for Grant County?: Zone 1 - highest potential (predicted average > 4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 3.4 pCi/L does not line up with Zone 1, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.
How much does radon mitigation cost in Grant County?: A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; Minnesota quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

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