Short-term kit
RA400 short-term liquid scintillation radon test kit, lab fee included
- Lab fee included
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Marquette County, Wisconsin
EPA puts Marquette County in Zone 2, its middle radon zone, and 15.0% of its 40 reported radon tests (2023) were 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
15.0%
20.7 pts below WI
- Marquette
- 15.0%
- Wisconsin
- 35.7%
40 tests, 2023
Median result
1.3pCi/L
Below action level
- Marquette
- 1.3 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
40
67th of 69 by tests
- Marquette
- 40
- Dane
- 2,887
Reported to CDC before any fix, 2023
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Wisconsin
66 of 69
Lowest quarter
- Marquette
- 15.0%
- Langlade
- 65.8%
By share, of 69 with 30+ tests
Read a result for Marquette County
Starts at Marquette County's median, 1.3 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 1.3 pCi/L
Below 2 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is below 2 pCi/L, the level at which EPA says a fix should be considered. Marquette County's median reported result, 2023.
The data
Marquette County, At a glance
Marquette County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Marquette County is a
USGS geologic potential: Moderate across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Marquette County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 30.8% |
| 2015 | 22.2% |
| 2016 | 20.9% |
| 2017 | 7.3% |
| 2019 | 14.8% |
| 2020 | 10.0% |
| 2021 | 21.1% |
| 2022 | 37.0% |
| 2023 | 15.0% |
2023: 15.0%. Across these years the share ran from 7.3% to 37.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 40 tests reported to CDC for Marquette 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).
Marquette County, Compared
Marquette County radon figures, compared
Calculated by Radon411Marquette County's 40 reported tests in 2023 had a middle value of 1.3 pCi/L and a maximum of 11.8 pCi/L, and 15.0% reached 4 pCi/L. Wisconsin as a whole (72 Wisconsin counties, pooled) comes to 35.7%: 20.7 points higher than here.
Among its state's counties it ranks 66th of 69 Wisconsin counties with 30 or more tests for the same period. Statewide for the same period, Langlade County reported the highest share (65.8%) and Bayfield County the lowest (5.7%).
Below the action level, 28 tests (70.0%) came in under 2 pCi/L, against 41.4% statewide, and 6 tests (15.0%) fell between 2 and 4, against 23.0% statewide. The busiest year on file was 2019, with 54 tests reported; the quietest, 2021, had 19.
EPA's 1993 zone map puts Marquette County in Zone 2, a predicted county average between 2 and 4 pCi/L. USGS geology rates 100% of the county's land moderate radon potential.
Next door, the shares run from 20.8% in Adams County to 40.5% in Green Lake County. Over 6 years of annual figures the share fell 7.2 points, from 22.2% in 2015 to 15.0% in 2023; its peak was 22.2% in 2015.
Marquette CountyWisconsin, pooled
15.0% % of tests35.7% % of tests
| Year | Tests | Marquette County, at or above 4 pCi/L | Wisconsin, pooled |
|---|---|---|---|
| 2015 | 36 | 22.2% | 51.6% |
| 2016 | 43 | 20.9% | 45.2% |
| 2017 | 41 | 7.3% | 44.8% |
| 2019 | 54 | 14.8% | 42.9% |
| 2020 | 30 | 10.0% | 27.0% |
| 2023 | 40 | 15.0% | 35.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Marquette County, Geology
The ground under Marquette County
PredictedUSGS's geologic map puts all of Marquette County's mapped land in one class: moderate radon potential. All of it lies in the area the map calls Green Bay Lobe, to which USGS gives a radon index of 10, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Green Bay Lobe | Glacial deposits derived from carbonate and igneous rocks. | Moderate | 10 | 99.9% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Marquette County beside the ground around it
Across Wisconsin 34.8% of the land is rated high; none of Marquette County's is. Of the 4 counties that border it, 2 have more high-potential ground, Green Lake County the most at 42.5%.
The map rates the ground, not the air in any home.
Local help
Marquette County, Local resources
Radon testing and mitigation in Marquette 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.
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
Marquette County, Questions
Questions about radon in Marquette County
Are radon levels high in Marquette County?
In 2023, 15.0% of the radon tests reported to CDC for Marquette County, Wisconsin were at or above 4 pCi/L, and the median reported pre-mitigation result was 1.3 pCi/L. Of 69 Wisconsin counties with 30 or more tests for the same period, 65 reported a higher share; pooled, the state comes to 35.7%.
Which counties border Marquette County?
Marquette County borders 4 counties: Green Lake County, Waushara County, Adams County and Columbia County.
Products
Marquette County, Products
Testing a home in Marquette County
In Marquette County, 15.0% of 40 tests reported to CDC in 2023 reached 4 pCi/L, against 35.7% pooled across Wisconsin. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Marquette County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
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
Monitor
Hello Radon C battery radon monitor with an e-ink screen
- C-NRPP 2024/25: Not included
- Battery
- Screen
Method: Alpha spectrometry
First reading: Within 24 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Marquette County, Bordering counties
Counties bordering Marquette County
Calculated by Radon411- Radon levels in Green Lake CountyEPA zone 1
40.5%at or above 4 pCi/L
Median 3.4 pCi/L · 79 tests · 25.5 points above Marquette County
- Radon levels in Columbia CountyEPA zone 2
28.8%at or above 4 pCi/L
Median 2.0 pCi/L · 163 tests · 13.8 points above Marquette County
- Radon levels in Waushara CountyEPA zone 2
25.4%at or above 4 pCi/L
Median 1.9 pCi/L · 71 tests · 10.4 points above Marquette County
- Radon levels in Adams CountyEPA zone 2
20.8%at or above 4 pCi/L
Median 1.7 pCi/L · 48 tests · 5.8 points above Marquette County
Marquette County, Cities and towns
Cities and towns in Marquette County
The Census Bureau estimates 15,927 residents in Marquette County for July 1, 2025, 333 more than in 2020 (+2.1%). That works out to 35 people per square mile of land. No town dominates: Montello, the largest, has 1,447 residents, 9.1% of the total. Together its 5 incorporated places hold 26.0% of those residents; the other 74.0% live outside any of them. CDC's 40 reported tests for 2023 work out to 2.5 per 1,000 residents (2025 estimate), close to Wisconsin's 3.5.
From Montello to Neshkoro, CDC publishes no figure by town: each reads Marquette County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Montello | 1,447 | +0.3% | 9.1% |
| Westfield | 1,317 | +1.2% | 8.3% |
| Oxford | 536 | Level | 3.4% |
| Endeavor | 426 | −0.2% | 2.7% |
| Neshkoro | 410 | −0.7% | 2.6% |
5 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).
Marquette County, Homes
Homes in Marquette County
Marquette County is a place of houses on their own lots: 83% of its 9,841 homes are detached single-family houses, against 66% across Wisconsin. Half of its homes were built before 1977, close to Wisconsin's 1975: 30% date from before 1960 and 17% from 2000 or later. Owners live in 81% of the occupied homes (Wisconsin: 68%), so for most households a test and a fix are their own to order.
| Homes | Marquette County | Wisconsin |
|---|---|---|
| Housing units | 9,841 | 2,750,750 |
| Detached houses | 83% | 66% |
| In buildings of 5 or more | 3% | 17% |
| Mobile homes | 11% | 3% |
| Built before 1960 | 30% | 34% |
| Built since 2000 | 17% | 20% |
| Middle year built | 1977 | 1975 |
| Owner-occupied | 81% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.