Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Nemaha County, Kansas
EPA puts Nemaha County in Zone 1, its highest radon zone, and only 28 radon tests from it are on file with CDC (2022). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
58.7%
23.3 pts above KS
- Nemaha
- 58.7%
- Kansas
- 35.4%
75 tests, 2016
Median result
5.8pCi/L
Action level reached
- Nemaha
- 5.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2016
Tests reported
75
24th of 38 by tests
- Nemaha
- 75
- Johnson
- 6,586
Reported to CDC before any fix, 2016
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Kansas
6 of 38
Top quarter
- Nemaha
- 58.7%
- Mitchell
- 78.4%
By share, of 38 with 30+ tests
Read a result for Nemaha County
Starts at Nemaha County's median, 5.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 5.8 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. Nemaha County's median reported result, 2016.
The data
Nemaha County, At a glance
Nemaha County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Nemaha County in
USGS geologic potential: High across 83% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Nemaha County, 2022
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2016 | 58.7% |
| 2017 | 58.5% |
| 2018 | 62.5% |
| 2019 | 60.0% |
| 2020 | 46.2% |
| 2021 | 53.8% |
| 2022 | 64.3% |
2022: 64.3%. Across these years the share ran from 46.2% to 64.3%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 28 tests were reported to CDC for Nemaha County over 2022, and tests are often run on homes being sold or already suspected of a problem: so few describe neither the county nor this house.
Measured: CDC tracking data. Figure above: 2022. Measured data period: 2016 to 2022 (every CDC figure on file).
Nemaha County, Compared
Nemaha County radon figures, compared
Calculated by Radon411More than half: 58.7% of the 75 radon tests reported to CDC for Nemaha County in 2016 read at least 4 pCi/L. That places it 6th of 38 Kansas counties with 30 or more tests for the same period. That is 23.3 points above the 35.4% pooled from 99 Kansas counties.
The newest figure, in 2022, counts only 28 tests (64.3% at or above 4 pCi/L), too few to compare, so this reading uses the 75-test figure.
The median result, 5.8 pCi/L, sits above EPA's 4 pCi/L action level, and the top reported result was 38.8 pCi/L. The rest split 18.7% under 2 pCi/L and 22.7% from 2 to 4 (Kansas: 36.1% and 28.5%). Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 58.7% share point the same way here.
1 of its 5 bordering counties with figures ran higher, led by Richardson County, NE at 72.6%; Jackson County reported 13.3%. Statewide for the same period, Mitchell County reported the highest share (78.4%) and Jackson County the lowest (13.3%).
The busiest year on file was 2016, with 75 tests reported; the quietest, 2022, had 28.
Over 6 years of annual figures the share fell 4.9 points, from 58.7% in 2016 to 53.8% in 2021; its peak was 62.5% in 2018. Nationally, every county with a figure for the same period pools to 31.2%; Nemaha County sits 27.5 points above it.
Nemaha CountyKansas, pooled
53.8% % of tests31.8% % of tests
| Year | Tests | Nemaha County, at or above 4 pCi/L | Kansas, pooled |
|---|---|---|---|
| 2016 | 75 | 58.7% | 35.4% |
| 2017 | 41 | 58.5% | 37.3% |
| 2018 | 64 | 62.5% | 37.3% |
| 2019 | 50 | 60.0% | 33.7% |
| 2020 | 52 | 46.2% | 31.3% |
| 2021 | 39 | 53.8% | 31.8% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Nemaha County, Geology
The ground under Nemaha County
PredictedMost of the ground under Nemaha County is one class on USGS's geologic map: 83.4% of its land is high radon potential, with 16.6% moderate. The map puts 83.4% of Nemaha County in the area it calls Glacial Drift and 16.6% in Glaciated Area. USGS gives the first a radon index of 12, in the high band (12 to 17), and the second 9, in the moderate band (9 to 11).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Glacial Drift | Glacial drift and loess of varying thickness, largely locally derived from underlying and nearby Paleozoic sedimentary rocks. | High | 12 | 83.4% |
| Glaciated Area | Glacial till underlain by Pennsylvanian and Permian marine and nonmarine sedimentary shale, sandstone, limestone, coal. | Moderate | 9 | 16.6% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Nemaha County beside the ground around it
Nemaha County has more high-potential ground than Kansas as a whole: 83.4% of its land against 59.9%. Of the 6 counties that border it, 4 have more high-potential ground, Marshall County the most at 99.6%.
The map rates the ground, not the air in any home.
Local help
Nemaha County, Local resources
Radon testing and mitigation in Nemaha County
- Kansas Radon ProgramKansas Radon Program answers questions about testing, mitigation and the rules in Kansas.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsAsk the program whether it has free or discounted kits, or compare kits you can buy.
- Compare kits
- Professionals in Kansas178 professionals are listed in Kansas.
What Kansas's program says
- Phone
- (800) 693-5343
What it means
Nemaha County, Questions
Questions about radon in Nemaha County
Are radon levels high in Nemaha County?
In 2022, 64.3% of the radon tests reported to CDC for Nemaha County, Kansas were at or above 4 pCi/L, and the median reported pre-mitigation result was 7.3 pCi/L. Of 38 Kansas counties with 30 or more tests for the same period, 5 reported a higher share; pooled, the state comes to 35.4%.
Which counties border Nemaha County?
Nemaha County borders 6 counties: Brown County, KS, Pawnee County, NE, Jackson County, KS, Richardson County, NE, Marshall County, KS and Pottawatomie County, KS.
Products
Nemaha County, Products
Testing a home in Nemaha County
In Nemaha County, 58.7% of 75 tests reported to CDC in 2016 reached 4 pCi/L, against 35.4% pooled across Kansas. In Zone 1 the year-round level in Nemaha 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 One battery digital radon monitor with an e-ink screen
- C-NRPP 2024/25: Not included
- Battery
- Bluetooth
- Alarm
- Screen, app
Method: Ion chamber
First reading: Within 10 minutes
Short-term kitKidde
442020 short-term charcoal radon test kit
- Lab fee included
Method: Charcoal
In home: 3 days
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Nemaha County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Nemaha County
Explore
Nemaha County, Bordering counties
Counties bordering Nemaha County
Calculated by Radon411- Radon levels in Richardson County, NEEPA zone 1
72.6%at or above 4 pCi/L
Median 5.9 pCi/L · 405 tests · 13.9 points above Nemaha County
- Radon levels in Brown County, KSEPA zone 1
68.0%at or above 4 pCi/L
Median 7.4 pCi/L · 25 tests · 9.3 points above Nemaha County
- Radon levels in Marshall County, KSEPA zone 1
42.9%at or above 4 pCi/L
Median 3.5 pCi/L · 49 tests · 15.8 points below Nemaha County
- Radon levels in Pawnee County, NEEPA zone 1
37.5%at or above 4 pCi/L
Median 3.0 pCi/L · 96 tests · 21.2 points below Nemaha County
- Radon levels in Pottawatomie County, KSEPA zone 1
33.1%at or above 4 pCi/L
Median 2.9 pCi/L · 151 tests · 25.6 points below Nemaha County
- Radon levels in Jackson County, KSEPA zone 1
13.3%at or above 4 pCi/L
Median 0.8 pCi/L · 83 tests · 45.4 points below Nemaha County
Nemaha County, Cities and towns
Cities and towns in Nemaha County
About 10,054 people live in Nemaha County by the Census Bureau's estimate for July 1, 2025, 214 fewer than in 2020 (−2.1%). That works out to 14 people per square mile of land. Sabetha, the largest place on its list (2,474 residents in all), extends beyond Nemaha County, so no share of the total is worked out for it. CDC's 75 reported tests for 2016 work out to 7.5 per 1,000 residents (2025 estimate), close to Kansas' 5.8.
From Sabetha to Oneida, CDC publishes no figure by town: each reads Nemaha County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Sabethaextends beyond Nemaha County | 2,474 | −2.6% | Counted whole |
| Seneca | 2,139 | +0.5% | 21.3% |
| Centralia | 485 | +1.5% | 4.8% |
| Wetmore | 338 | −3.4% | 3.4% |
| Corning | 206 | −2.8% | 2.0% |
| Bern | 161 | −3.0% | 1.6% |
| Goff | 107 | +0.9% | 1.1% |
| Oneida | 58 | −3.3% | 0.6% |
8 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). A place that extends beyond Nemaha County is counted whole, so it has no share.
Nemaha County, Homes
Homes in Nemaha County
Nemaha County is a place of houses on their own lots: 82% of its 4,501 homes are detached single-family houses, against 72% across Kansas. Half of its homes were built before 1974, close to Kansas' 1975: 38% date from before 1960 and 21% from 2000 or later. Owners live in 79% of the occupied homes (Kansas: 67%), so for most households a test and a fix are their own to order.
| Homes | Nemaha County | Kansas |
|---|---|---|
| Housing units | 4,501 | 1,285,221 |
| Detached houses | 82% | 72% |
| In buildings of 5 or more | 6% | 13% |
| Mobile homes | 4% | 4% |
| Built before 1960 | 38% | 33% |
| Built since 2000 | 21% | 20% |
| Middle year built | 1974 | 1975 |
| Owner-occupied | 79% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.