Radon levels in Lawrence County, South Dakota

HighEPA Zone 2

Predicted long-term basement average of 4.4 pCi/L (model estimate) across 6 ZIP codes - about 2.4× the US average of 1.8, close to the South Dakota average of 3.9. Ranked #17 of 66 South Dakota counties.

Test Lawrence County, SD now - and consider a continuous monitor

The model predicts a long-term basement average of 4.4 pCi/L here, at or above the EPA action level of 4. Homes in the same ZIP still vary widely, so a real test is the only way to know your number. A continuous digital monitor shows how your level swings with weather and season, which matters when you're near the action level.

Already tested at 4 pCi/L or higher? Find a certified mitigation professional (EPA). A mitigation system typically runs $800-$2,500 installed.

We may earn a commission from Amazon at no extra cost to you.

Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.

4.4 ± 0.07

pCi/L predicted basement mean (model SD)

2.2 ± 0.06

pCi/L predicted upstairs (above-ground) mean

2.6-5.1

range of ZIP-level basement predictions in the county

What this means for Lawrence

The typical home in Lawrence County is predicted to sit at or above the EPA action level of 4 pCi/L in the basement. In practice that means a large share of houses here would qualify for mitigation if tested, and buyers routinely ask for radon tests in South Dakota transactions.

Note that the EPA classifies Lawrence County as Zone 2 while the newer model predicts 4.4 pCi/L. The zone map predates two decades of test data; where they disagree, we grade on the model but show both. County figures weight each ZIP by its 2010 Census population, so they describe where people live rather than empty land.

Comparable South Dakota counties: Brule County (4.4), Charles Mix County (4.4), Sanborn County (4.4), Miner County (4.4). The state's highest is Jerauld County at 5.2 pCi/L.

ZIP codes in Lawrence County

Predicted basement and upstairs means by ZIP (model estimate). ZIPs whose land is mostly in this county.

ZIPBasementUpstairsGrade
577835.1 ± 0.082.3High
577543.1 ± 0.062.0Moderate
577323.2 ± 0.052.0Moderate
577933.7 ± 0.062.2Moderate
577592.6 ± 0.071.4Moderate
577793.6 ± 0.061.9Moderate

If your test comes back at 4 pCi/L or higher

Mitigation is a routine job: a fan-driven pipe that vents soil gas from under the slab to above the roofline, typically $800-$2,500 installed (typical range; local quotes vary). Use certified professionals: EPA find-a-professional. Read the full mitigation guide.

Lawrence County radon questions

Is radon high in Lawrence County, South Dakota?
High. The model predicts a long-term basement average of 4.4 pCi/L in Lawrence County (about 2.4× the US average of 1.8 and close to the South Dakota average of 3.9). That is at or above the EPA action level of 4 pCi/L, so the typical home here would qualify for mitigation. Ranked 17 of 66 South Dakota counties.
Should I test for radon in Lawrence County?
Yes, soon. With a predicted average of 4.4 pCi/L and at least one ZIP predicted at 5.1, many homes in Lawrence County will test above the 4 pCi/L action level. Use a short-term kit first; if it reads 2 or higher, confirm with a long-term test or continuous monitor before deciding on mitigation.
What does EPA Radon Zone 2 mean for Lawrence County?
Zone 2 - moderate potential (2-4 pCi/L). The zone map dates from 1993 and classifies whole counties. The newer model's predicted average of 4.4 pCi/L does not line up with Zone 2, which is common - the EPA itself says high-radon homes exist in every zone. Neither replaces a test of your own home.
How much does radon mitigation cost in Lawrence County?
A standard active sub-slab depressurization system typically runs $800-$2,500 installed nationally; South Dakota quotes vary with foundation type (slab, crawlspace, basement), home size and local labor. Get two or three bids from certified mitigators listed by your state radon program or the EPA's find-a-professional page.

← All South Dakota counties · How to test · Radon in a home sale · Methodology