Short-term kitempowerDX
Standard Radon Test short-term mail-in radon test kit
- Lab fee included
Method: Passive sampler
In home: 48 to 96 hours
Locations and reports
Radon Levels in Bennett County, South Dakota
EPA puts Bennett County in Zone 2, its middle radon zone, and only 3 radon tests from it are on file with CDC (2008 to 2017, laboratory totals). Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Highest bordering
38.5%
Sheridan County
- Sheridan
- 38.5%
1 of 6 neighbours have 30+ tests, 2006 to 2015
Nearest county
51.8%
Pennington County, 81 miles
- Pennington
- 51.8%
- SD
- 58.8%
Share at 4+ pCi/L, 786 tests, 2006 to 2015
Ground above low
80.5%
18.6 pts below SD
- Bennett
- 80.5%
- SD
- 99.0%
Share of land USGS rates moderate or high potential
Tests reported
3
Too few for a share
- Bennett
- 3
- Needed
- 30
2008 to 2017, laboratory
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Read a result for Bennett County
Starts at EPA's action level
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 4.0 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.
The data
Bennett County, At a glance
Bennett County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Bennett County is a
USGS geologic potential: Moderate across 80% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Bennett County, 2008 to 2017, laboratory
CDC holds 3 reported tests for Bennett County over the 2008 to 2017 laboratory totals, with a median of 3.0 pCi/L: too few to describe a county (Radon411 reads a share from 30 tests up). Bennett County beside the counties around it is how this page reads it.
What these figures count
Only 3 tests were reported to CDC for Bennett County over 2008 to 2017 (laboratory totals), 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: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Bennett County, Compared
Bennett County radon figures, compared
Calculated by Radon411CDC's largest figure for Bennett County rests on 3 tests over the 2008 to 2017 laboratory totals, 1 of them at or above 4 pCi/L, so each test moves its share by 33.3 points and no rank or comparison is drawn from it. Results reached as high as 7.8 pCi/L, with a middle value of 3.0 pCi/L.
Sheridan County, NE, the one bordering county with a figure over the 2006 to 2015 laboratory totals, reported 38.5% of its tests at or above 4 pCi/L. Farther out, Pennington County (81 miles away) at 51.8%, Custer County (96 miles away) at 68.3% and Meade County (108 miles away) at 54.5% have figures too. Pooled across 63 South Dakota counties, 58.8% of reported tests reached that level; across every county in the country with a figure, 36.3%.
Statewide for the same period, Bon Homme County reported the highest share (79.5%) and Davison County the lowest (47.9%). EPA's 1993 map puts Bennett County in Zone 2, its middle label: a predicted county average between 2 and 4 pCi/L. USGS geology rates 80% of the county's land moderate radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Bennett County, Geology
The ground under Bennett County
PredictedMost of the ground under Bennett County is one class on USGS's geologic map: 80.5% of its land is moderate radon potential, with 19.5% low. The map puts 80.5% of Bennett County in the area it calls Southern Plateaus and 19.5% in Sand Hills. USGS gives the first a radon index of 11, in the moderate band (9 to 11), and the second 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Southern Plateaus | Late Tertiary continental sandstone. | Moderate | 11 | 80.5% |
| Sand Hills | Tertiary sandstone, siltstone, shale. | Low | 8 | 19.5% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Bennett County beside the ground around it
Across South Dakota 56.7% of the land is rated high; none of Bennett County's is. Of the 6 counties that border it, 1 has more high-potential ground, Sheridan County, NE the most at 0.3%.
The map rates the ground, not the air in any home.
Local help
Bennett County, Local resources
Radon testing and mitigation in Bennett County
- South Dakota's radon programDepartment of Agriculture and Natural ResourcesSouth Dakota's radon program offers free or discounted test kits, and answers questions about testing and mitigation in South Dakota.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
The Department of Agriculture and Natural Resources (DANR) will provide 500 free Radon test kits to South Dakota Residents.
- Compare kits
- Professionals in South Dakota5 professionals are listed in South Dakota.
What South Dakota's program says
- Phone
- 1-800-438-3367
What it means
Bennett County, Questions
Questions about radon in Bennett County
Are radon levels high in Bennett County?
Over the 2008 to 2017 laboratory totals, 33.3% of the radon tests reported to CDC for Bennett County, South Dakota were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.0 pCi/L. Sheridan County, NE, the one bordering county with a figure over the 2006 to 2015 laboratory totals, reported 38.5% of its tests at or above 4 pCi/L.
Which counties border Bennett County?
Bennett County borders 6 counties: Jackson County, SD, Oglala Lakota County, SD, Todd County, SD, Mellette County, SD, Cherry County, NE and Sheridan County, NE.
Products
Bennett County, Products
Testing a home in Bennett County
No CDC figure names Bennett County; the nearest county with one, Pennington County (81 miles away), reported 51.8% of its tests at or above 4 pCi/L over the 2006 to 2015 laboratory totals, the only reading nearby until a test of this home. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Bennett 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
EcoQube Wi-Fi continuous radon monitor
- C-NRPP 2024/25: Approved
- Plug-in
- Wi-Fi
- App only
Method: Ion chamber
First reading: Within 10 minutes
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Bennett County, Bordering counties
Counties bordering Bennett County
Calculated by Radon411- Radon levels in Sheridan County, NEEPA zone 2
38.5%at or above 4 pCi/L
Median 2.9 pCi/L · 109 tests
- Radon levels in Cherry County, NEEPA zone 3
4.5%at or above 4 pCi/L
Median 1.9 pCi/L · 22 tests
- Radon levels in Jackson County, SDEPA zone 2
0.0%at or above 4 pCi/L
Median 1.1 pCi/L · 1 test
- Radon levels in Oglala Lakota County, SDEPA zone 2
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
- Radon levels in Todd County, SDEPA zone 2
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
- Radon levels in Mellette County, SDEPA zone 2
No CDC figure for 2006 to 2015; its page reads it against its own neighbours.
Bennett County, Cities and towns
Cities and towns in Bennett County
About 3,307 people live in Bennett County by the Census Bureau's estimate for July 1, 2025, 90 fewer than in 2020 (−2.6%). Spread over its land, that is 2.8 people to the square mile. Martin, its one incorporated place, has 930 residents, 28.1% of the total. Reported testing is thin here: 3 tests over 2008 to 2017, or 0.9 for every 1,000 residents (2025 estimate), where South Dakota as a whole comes to 6.7.
Martin is the one incorporated place here; CDC publishes no figure by town, so it reads Bennett County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Martin | 930 | −1.7% | 28.1% |
One incorporated place, 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).
Bennett County, Homes
Homes in Bennett County
Bennett County is a place of houses on their own lots: 82% of its 1,232 homes are detached single-family houses, against 67% across South Dakota. Half of its homes were built before 1972, close to South Dakota's 1979: 39% date from before 1960 and 5% from 2000 or later. 58% of occupied homes are lived in by their owner (South Dakota: 69%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Bennett County | South Dakota |
|---|---|---|
| Housing units | 1,232 | 402,364 |
| Detached houses | 82% | 67% |
| In buildings of 5 or more | 3% | 16% |
| Mobile homes | 11% | 8% |
| Built before 1960 | 39% | 29% |
| Built since 2000 | 5% | 28% |
| Middle year built | 1972 | 1979 |
| Owner-occupied | 58% | 69% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.