Is radon high in Cass County, Minnesota?

Moderate. The model predicts a long-term basement average of 2.5 pCi/L in Cass County (about 1.4× the US average of 1.8 and close to the Minnesota average of 2.4). That is in the 2-4 pCi/L range where the EPA recommends considering mitigation. Ranked 61 of 87 Minnesota counties.

Should I test for radon in Cass County?

Yes, soon. With a predicted average of 2.5 pCi/L, many homes in Cass 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 2 mean for Cass County?

Zone 2 - moderate potential (2-4 pCi/L). The zone map dates from 1993 and classifies whole counties. The 2001-2021 model agrees with the zone here. Neither replaces a test of your own home.

How much does radon mitigation cost in Cass 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 Cass County, Minnesota

ModerateEPA Zone 2

Predicted long-term basement average of 2.5 pCi/L (model estimate) across 13 ZIP codes - about 1.4× the US average of 1.8, close to the Minnesota average of 2.4. Ranked #61 of 87 Minnesota counties.

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

The predicted basement average here is 2.5 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.

2.5 ± 0.07

pCi/L predicted basement mean (model SD)

1.4 ± 0.08

pCi/L predicted upstairs (above-ground) mean

1.7-3.0

range of ZIP-level basement predictions in the county

Measured tests in Cass 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: 3.2 pCi/L
Median: 2.7 pCi/L
Tests ≥ 4 pCi/L: 31.6%
Tests per year: 75

Source: MN Public Health Data Access.

What this means for Cass

The typical Cass 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.

The 1993 EPA zone (2) and the 2001-2021 model agree for Cass. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable Minnesota counties: Hubbard County (2.6), Wright County (2.6), Stearns County (2.6), Morrison County (2.4). The state's highest is Rock County at 4.7 pCi/L.

ZIP codes in Cass County

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

ZIP	Basement	Upstairs	Grade
56472	2.3 ± 0.11	1.1	Moderate
56633	2.0 ± 0.07	0.9	Moderate
56474	2.7 ± 0.07	1.6	Moderate
56473	2.8 ± 0.06	1.8	Moderate
56484	2.7 ± 0.05	1.6	Moderate
56466	2.6 ± 0.06	1.3	Moderate
56435	2.7 ± 0.07	1.6	Moderate
56672	2.7 ± 0.06	1.6	Moderate
56452	3.0 ± 0.06	1.8	Moderate
56655	2.8 ± 0.07	1.8	Moderate
56662	2.2 ± 0.06	1.2	Moderate
56626	1.7 ± 0.06	0.9	Low
56641	2.8 ± 0.06	1.7	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.

Cass County radon questions

Is radon high in Cass County, Minnesota?: Moderate. The model predicts a long-term basement average of 2.5 pCi/L in Cass County (about 1.4× the US average of 1.8 and close to the Minnesota average of 2.4). That is in the 2-4 pCi/L range where the EPA recommends considering mitigation. Ranked 61 of 87 Minnesota counties.
Should I test for radon in Cass County?: Yes, soon. With a predicted average of 2.5 pCi/L, many homes in Cass 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 2 mean for Cass County?: Zone 2 - moderate potential (2-4 pCi/L). The zone map dates from 1993 and classifies whole counties. The 2001-2021 model agrees with the zone here. Neither replaces a test of your own home.
How much does radon mitigation cost in Cass 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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