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 Grant County, Kansas
EPA puts Grant County in Zone 1, its highest radon zone, and only 2 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
Highest bordering
30.1%
Finney County
- Finney
- 30.1%
1 of 6 neighbours have 30+ tests, 2019
Nearest county
52.2%
Seward County, 36 miles
- Seward
- 52.2%
- Kansas
- 33.7%
Share at 4+ pCi/L, 92 tests, 2019
Ground above low
100.0%
Level with Kansas
- Grant
- 100.0%
- Kansas
- 100.0%
Share of land USGS rates moderate or high potential
Tests reported
27
Too few for a share
- Grant
- 27
- Needed
- 30
2021
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Read a result for Grant 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
Grant County, At a glance
Grant County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Grant County in
USGS geologic potential: High across 81% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Grant County, 2022
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2016 | 90.0% |
| 2017 | 8.0% |
| 2018 | 75.0% |
| 2019 | 55.6% |
| 2020 | 25.0% |
| 2021 | 11.1% |
| 2022 | 0.0% |
2022: 0.0%. Across these years the share ran from 0.0% to 90.0%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
Only 2 tests were reported to CDC for Grant 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).
Grant County, Compared
Grant County radon figures, compared
Calculated by Radon411CDC's largest figure for Grant County rests on 27 tests in 2021, 3 of them at or above 4 pCi/L, so each test moves its share by 3.7 points and no rank or comparison is drawn from it. Results reached as high as 4.4 pCi/L, with a middle value of 2.1 pCi/L.
Finney County, the one bordering county with a figure in 2019, reported 30.1% of its tests at or above 4 pCi/L. Farther out, Seward County (36 miles away) at 52.2%, Scott County (67 miles away) at 61.5% and Ford County (78 miles away) at 42.4% have figures too. Pooled across 102 Kansas counties, 33.7% of reported tests reached that level; across every county in the country with a figure, 29.0%.
Statewide for the same period, Jewell County reported the highest share (71.9%) and Reno County the lowest (20.8%). EPA's 1993 map puts Grant County in Zone 1, the map's highest label: a predicted county average above 4 pCi/L. USGS geology rates 81% of the county's land high radon potential.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Grant County, Geology
The ground under Grant County
PredictedMost of the ground under Grant County is one class on USGS's geologic map: 80.8% of its land is high radon potential, with 19.2% moderate. The map puts 80.8% of Grant County in the area it calls Ogallala Formation and 16.1% in Cimmaron River Valley, with one smaller area beside them. 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 |
|---|---|---|---|---|
| Ogallala Formation | Tertiary sandstone, in part covered by windblown eolian sand and loess deposits. | High | 12 | 80.8% |
| Cimmaron River Valley | Tertiary and Quaternary sandstone, siltstone, shale, and alluvium overlain by eolian sand and loess. | Moderate | 10 | 16.1% |
| Arkansas River Lowlands | Dune sands and alluvium. | Moderate | 10 | 3.1% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Grant County beside the ground around it
Grant County has more high-potential ground than Kansas as a whole: 80.8% of its land against 59.9%. Of the 6 counties that border it, 3 have more high-potential ground, Stanton County the most at 100%.
The map rates the ground, not the air in any home.
Local help
Grant County, Local resources
Radon testing and mitigation in Grant 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
Grant County, Questions
Questions about radon in Grant County
Are radon levels high in Grant County?
In 2022, 0.0% of the radon tests reported to CDC for Grant County, Kansas were at or above 4 pCi/L, and the median reported pre-mitigation result was 2.8 pCi/L. Finney County, the one bordering county with a figure in 2019, reported 30.1% of its tests at or above 4 pCi/L.
Which counties border Grant County?
Grant County borders 6 counties: Haskell County, Stevens County, Stanton County, Kearny County, Finney County and Hamilton County.
Products
Grant County, Products
Testing a home in Grant County
No CDC figure names Grant County; the nearest county with one, Seward County (36 miles away), reported 52.2% of its tests at or above 4 pCi/L in 2019, the only reading nearby until a test of this home. In Zone 1 the year-round level in Grant 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
MonitorAEGTEST
HOUND-1011S rechargeable radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 12 hours
Short-term kit
PicoCan short-term charcoal canister radon test
- Lab fee included
Method: Charcoal
In home: 48 to 96 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Grant County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Grant County
Explore
Grant County, Bordering counties
Counties bordering Grant County
Calculated by Radon411- Radon levels in Kearny CountyEPA zone 1
62.5%at or above 4 pCi/L
Median 5.5 pCi/L · 8 tests
- Radon levels in Haskell CountyEPA zone 1
50.0%at or above 4 pCi/L
Median 5.5 pCi/L · 2 tests
- Radon levels in Stevens CountyEPA zone 2
36.0%at or above 4 pCi/L
Median 2.6 pCi/L · 25 tests
- Radon levels in Finney CountyEPA zone 1
30.1%at or above 4 pCi/L
Median 3.0 pCi/L · 156 tests
- Radon levels in Stanton CountyEPA zone 1
0.0%at or above 4 pCi/L
Median 3.9 pCi/L · 1 test
- Radon levels in Hamilton CountyEPA zone 1
0.0%at or above 4 pCi/L
Median 3.1 pCi/L · 2 tests
Grant County, Cities and towns
Cities and towns in Grant County
About 7,028 people live in Grant County by the Census Bureau's estimate for July 1, 2025, 297 fewer than in 2020 (−4.1%). That works out to 12 people per square mile of land. Ulysses, its one incorporated place, has 5,524 residents, 78.6% of the total. Reported testing is thin here: 27 tests over 2021, or 3.8 for every 1,000 residents (2025 estimate), where Kansas as a whole comes to 23.5.
Ulysses is the one incorporated place here; CDC publishes no figure by town, so it reads Grant County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Ulysses | 5,524 | −4.3% | 78.6% |
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).
Grant County, Homes
Homes in Grant County
Of Grant County's 2,932 homes, 66% are detached houses, against 72% across Kansas; 17% are mobile homes. Half of its homes were built before 1979, close to Kansas' 1975: 28% date from before 1960 and 14% from 2000 or later. 75% of occupied homes are lived in by their owner (Kansas: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Grant County | Kansas |
|---|---|---|
| Housing units | 2,932 | 1,285,221 |
| Detached houses | 66% | 72% |
| In buildings of 5 or more | 2% | 13% |
| Mobile homes | 17% | 4% |
| Built before 1960 | 28% | 33% |
| Built since 2000 | 14% | 20% |
| Middle year built | 1979 | 1975 |
| Owner-occupied | 75% | 67% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.