Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Buffalo County, Wisconsin
EPA puts Buffalo County in Zone 1, its highest radon zone, and high results are common there: 53.6% of the 56 radon tests reported to CDC (2023) came back at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
53.6%
17.9 pts above WI
- Buffalo
- 53.6%
- Wisconsin
- 35.7%
56 tests, 2023
Median result
4.4pCi/L
Action level reached
- Buffalo
- 4.4 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
56
55th of 69 by tests
- Buffalo
- 56
- Dane
- 2,887
Reported to CDC before any fix, 2023
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Wisconsin
6 of 69
Top quarter
- Buffalo
- 53.6%
- Langlade
- 65.8%
By share, of 69 with 30+ tests
Read a result for Buffalo County
Starts at Buffalo County's median, 4.4 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.4 pCi/L
At or above 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. Buffalo County's median reported result, 2023.
The data
Buffalo County, At a glance
Buffalo County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Buffalo County in
USGS geologic potential: High across 84% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Buffalo County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 51.5% |
| 2015 | 54.5% |
| 2016 | 59.6% |
| 2017 | 51.2% |
| 2019 | 38.0% |
| 2020 | 51.7% |
| 2021 | 55.6% |
| 2022 | 60.0% |
| 2023 | 53.6% |
2023: 53.6%. Across these years the share ran from 38.0% to 60.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 56 tests reported to CDC for Buffalo County over 2023, many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Buffalo County, Compared
Buffalo County radon figures, compared
Calculated by Radon411More than half: 53.6% of the 56 radon tests reported to CDC for Buffalo County in 2023 read at least 4 pCi/L. That places it 6th of 69 Wisconsin counties with 30 or more tests for the same period. That is 17.9 points above the 35.7% pooled from 72 Wisconsin counties.
The median result, 4.4 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 38.2 pCi/L. The rest split 19.6% under 2 pCi/L and 26.8% from 2 to 4 (Wisconsin: 41.4% and 23.0%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 53.6% share point the same way here.
No bordering county with a figure for the same period reported a higher share; the closest is Wabasha County, MN at 42.3%, the lowest Pepin County at 15.4%. Statewide for the same period, Langlade County reported the highest share (65.8%) and Bayfield County the lowest (5.7%).
The busiest year on file was 2016, with 104 tests reported; the quietest, 2021, had 9.
Over 7 years of annual figures the share rose 2.1 points, from 51.5% in 2014 to 53.6% in 2023; its peak was 60.0% in 2022. Nationally, every county with a figure for the same period pools to 33.4%; Buffalo County sits 20.2 points above it. CDC also counts 6 tests taken after mitigation in Buffalo County for the same period: tests in homes where a fix was already in.
Buffalo CountyWisconsin, pooled
53.6% % of tests35.7% % of tests
| Year | Tests | Buffalo County, at or above 4 pCi/L | Wisconsin, pooled |
|---|---|---|---|
| 2014 | 33 | 51.5% | 51.1% |
| 2015 | 44 | 54.5% | 51.6% |
| 2016 | 104 | 59.6% | 45.2% |
| 2017 | 82 | 51.2% | 44.8% |
| 2019 | 50 | 38.0% | 42.9% |
| 2022 | 30 | 60.0% | 42.9% |
| 2023 | 56 | 53.6% | 35.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Buffalo County, Geology
The ground under Buffalo County
PredictedMost of the ground under Buffalo County is one class on USGS's geologic map: 84.2% of its land is high radon potential, with 15.8% moderate. The map puts 84.0% of Buffalo County in the area it calls Driftless Area and 15.8% in Driftless Area. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 10, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Driftless Area | Ordovician carbonate rocks. | High | 12 | 84.0% |
| Driftless Area | Cambrian sandstone. | Moderate | 10 | 15.8% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Buffalo County beside the ground around it
Buffalo County has more high-potential ground than Wisconsin as a whole: 84.2% of its land against 34.8%. Of the 5 counties that border it, 2 have more high-potential ground, Wabasha County, MN the most at 100%.
The map rates the ground, not the air in any home.
Local help
Buffalo County, Local resources
Radon testing and mitigation in Buffalo County
Listed radon businesses with an address in Buffalo County:
- Wisconsin's radon programWisconsin Department of Health ServicesWisconsin's radon program does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Wisconsin.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
We recommend starting with your regional Radon Information Center since many centers provide test kits for free or reduced cost, and often with laboratory fees covered.
- Compare kits
- Professionals in Wisconsin19 professionals are listed in Wisconsin.
Listed radon professionals by town: Fountain City
What Wisconsin's program says
- Phone
- 1-888-569-7236
- DHSRadon@dhs.wisconsin.gov
- Licensing of radon professionals
The State of Wisconsin does not require contractors performing radon measurement or mitigation work to be state licensed or nationally certified.
What it means
Buffalo County, Questions
Questions about radon in Buffalo County
Are radon levels high in Buffalo County?
In 2023, 53.6% of the radon tests reported to CDC for Buffalo County, Wisconsin were at or above 4 pCi/L, and the median reported pre-mitigation result was 4.4 pCi/L. Of 69 Wisconsin counties with 30 or more tests for the same period, 5 reported a higher share; pooled, the state comes to 35.7%.
Which counties border Buffalo County?
Buffalo County borders 5 counties: Trempealeau County, WI, Winona County, MN, Pepin County, WI, Wabasha County, MN and Eau Claire County, WI.
Products
Buffalo County, Products
Testing a home in Buffalo County
In Buffalo County, 53.6% of 56 tests reported to CDC in 2023 reached 4 pCi/L, against 35.7% pooled across Wisconsin. In Zone 1 the year-round level in Buffalo County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.
Test kits and monitors3
See every kit and monitor
MonitorAranet
Radon Plus battery digital radon monitor with an e-ink screen
- C-NRPP 2024/25: Approved
- Battery
- Bluetooth
- Alarm
- Screen, app
Method: Ion chamber
First reading: Within 10 minutes
Short-term kit
RA100 short-term liquid scintillation radon test kit
- Lab fee extra
Method: Liquid scintillation
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Buffalo County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Buffalo County
Explore
Buffalo County, Bordering counties
Counties bordering Buffalo County
Calculated by Radon411- Radon levels in Wabasha County, MNEPA zone 1
42.3%at or above 4 pCi/L
Median 3.3 pCi/L · 111 tests · 11.3 points below Buffalo County
- Radon levels in Trempealeau County, WIEPA zone 2
42.0%at or above 4 pCi/L
Median 3.3 pCi/L · 112 tests · 11.6 points below Buffalo County
- Radon levels in Winona County, MNEPA zone 1
38.8%at or above 4 pCi/L
Median 3.0 pCi/L · 139 tests · 14.8 points below Buffalo County
- Radon levels in Eau Claire County, WIEPA zone 2
32.7%at or above 4 pCi/L
Median 2.8 pCi/L · 474 tests · 20.9 points below Buffalo County
- Radon levels in Pepin County, WIEPA zone 1
15.4%at or above 4 pCi/L
Median 1.2 pCi/L · 65 tests · 38.2 points below Buffalo County
Buffalo County, Cities and towns
Cities and towns in Buffalo County
Buffalo County's population has barely moved since 2020: 13,318 residents on July 1, 2025 against 13,333 then, by the Census Bureau's estimates. That works out to 20 people per square mile of land. Its largest town, Mondovi, has 2,853 residents, 21.4% of the total. Together its 6 incorporated places hold 45.6% of those residents; the other 54.4% live outside any of them. CDC's 56 reported tests for 2023 work out to 4.2 per 1,000 residents (2025 estimate), close to Wisconsin's 3.5.
From Mondovi to Nelson, CDC publishes no figure by town: each reads Buffalo County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Mondovi | 2,853 | +0.1% | 21.4% |
| Buffalo City | 1,009 | −0.2% | 7.6% |
| Fountain City | 769 | −4.2% | 5.8% |
| Alma | 718 | Level | 5.4% |
| Cochrane | 416 | −2.3% | 3.1% |
| Nelson | 314 | −1.9% | 2.4% |
6 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025).
Buffalo County, Homes
Homes in Buffalo County
Buffalo County is a place of houses on their own lots: 82% of its 6,546 homes are detached single-family houses, against 66% across Wisconsin. Half of its homes were built before 1970, close to Wisconsin's 1975: 42% date from before 1960 and 17% from 2000 or later. Owners live in 78% of the occupied homes (Wisconsin: 68%), so for most households a test and a fix are their own to order.
| Homes | Buffalo County | Wisconsin |
|---|---|---|
| Housing units | 6,546 | 2,750,750 |
| Detached houses | 82% | 66% |
| In buildings of 5 or more | 5% | 17% |
| Mobile homes | 6% | 3% |
| Built before 1960 | 42% | 34% |
| Built since 2000 | 17% | 20% |
| Middle year built | 1970 | 1975 |
| Owner-occupied | 78% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.