Ontario, WI Radon Mitigation and Testing

Q: What EPA Radon Zone is Ontario in?

Ontario is in Vernon County, EPA Zone 1.

Q: How much does radon mitigation cost in Ontario?

Radon mitigation typically costs between $800 and $2,000. Most standard systems fall in the $1,000-$1,500 range.

Vernon County

EPA Zone 1

Ontario in Vernon County near the La Crosse Metro area has limited radon testing data available for residents. Wisconsin's driftless region features limestone bedrock that can contribute to elevated radon levels in homes with basements or lower-level living spaces. Testing is particularly important given the EPA Zone 1 designation for this area.

Ontario, WI Radon Mitigation

Professional radon mitigation is the most effective way to permanently lower radon levels and protect your household.

Ontario, WI Radon Testing

Finding qualified radon testing professionals is the first step toward protecting your home.

Ontario Radon Facts

Key details about the radon risk profile for Ontario and the 54651 zip code area.

EPA Radon Zone

Zone 1 — High Risk

County

Vernon County, WI

Zip Code

54651

Predicted Screening Level

> 4.0 pCi/L (Zone 1)

Ontario and the 54651 zip code are located in Vernon County, which has an EPA assigned Radon Zone of 1. A radon zone of 1 predicts an average indoor radon screening level greater than 4 pCi/L. The EPA recommends testing every home regardless of zone classification.

Radon FAQ for Ontario, WI

What EPA Radon Zone is Ontario in?

Ontario and the 54651 zip code are in Vernon County, which has an EPA assigned Radon Zone of 1. A zone of 1 predicts an average indoor radon screening level greater than 4 pCi/L.

How much does radon mitigation cost in Ontario?

Radon mitigation in Ontario typically costs between $800 and $2,000. Most homes with standard basements can be mitigated with a sub-slab depressurization system in the $1,000–$1,500 range. Factors that can increase cost include complex foundations, crawl spaces, or very high radon levels.

Should I test for radon if I'm buying a home in Ontario?

Yes. Radon testing should be part of every home purchase. A short-term radon test is typically included as part of the home inspection process and costs $150–$250. If elevated levels are found, you can negotiate mitigation as part of the sale.

Most Active Radon Markets in Wisconsin

Cities with the most user-submitted radon test data in the state.

City	Avg User Radon Level	Submissions
Milwaukee	10.00 pCi/L	3
Prairie Du Chien	10.00 pCi/L	2
Stevens Point	5.50 pCi/L	2
Menomonie	10.00 pCi/L	1
Delavan	6.00 pCi/L	1
Shawano	No submissions	0
Sturgeon Bay	No submissions	0