Portage Des Sioux, MO Radon Levels

Q: What EPA Radon Zone is Portage Des Sioux in?

Portage Des Sioux is in St Charles County, EPA Zone Unknown.

Q: How much does radon mitigation cost in Portage Des Sioux?

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

Check local Portage Des Sioux radon levels and find certified testing and mitigation professionals to keep your home safe

Portage Des Sioux, MO Radon Facts

EPA Radon Zone Unknown Unknown

County St Charles County, MO

Zip Code 63373

This historic Missouri River town in St. Charles County sits on floodplain deposits within the greater St. Louis metropolitan region. Radon testing data remains limited for zip code 63373, making professional home testing crucial for residents. The community's location on river alluvium over limestone bedrock, combined with its mix of historic and modern housing, creates variable conditions for radon accumulation.

6.63

pCi/L area average

Above EPA Action Level

St Charles County average: 6.63 pCi/L, based on 8 user-submitted tests across 5 cities in the county. No homeowner readings have been submitted for Portage Des Sioux itself yet, so this county figure is the closest available benchmark. The EPA recommends taking action at or above 4.0 pCi/L.

4.0 EPA

10+

Portage Des Sioux, MO Radon Mitigation

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

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Radon Readings Near Portage Des Sioux, MO

No homeowner tests have been submitted for Portage Des Sioux yet. The closest cities with user-submitted radon data are shown below — explore them to gauge local conditions. Radon varies by home, so testing is the only way to know your level.

City	Distance	Avg User Level	Readings
Hazelwood	10.1 mi	20.00 pCi/L	1
Saint Charles	14.4 mi	5.00 pCi/L	1
Saint Peters	16.2 mi	7.00 pCi/L	1
O Fallon	21.1 mi	7.75 pCi/L	4
Chesterfield	22.2 mi	5.00 pCi/L	1
Lake Saint Louis	23.3 mi	5.00 pCi/L	2
Ballwin	24.5 mi	4.00 pCi/L	1
Fenton	29.7 mi	16.00 pCi/L	2

St Charles County Radon Profile

A specific EPA radon zone has not been established for St Charles County, which is why testing is advised for all homes here irrespective of geology. Homeowner-submitted tests from 5 cities in St Charles County average 6.63 pCi/L across 8 tests — above the EPA's 4 pCi/L action level, reinforcing the need for testing across the county. Since radon is the second leading cause of lung cancer nationally, the EPA urges every household in St Charles County to test, as levels can differ between neighboring homes.

Radon FAQ for Portage Des Sioux, MO

What EPA Radon Zone is Portage Des Sioux in?

Portage Des Sioux and the 63373 zip code are in St Charles County, which has an EPA assigned Radon Zone of Unknown. A zone of Unknown does not have sufficient data for classification.

Why are radon readings shown from areas near Portage Des Sioux?

No homeowner radon tests have been submitted for Portage Des Sioux yet. Because radon is driven by regional soil and bedrock geology, readings from the closest cities—and the St Charles County average—are the best available indicator of local conditions until Portage Des Sioux homeowners submit their own results. The EPA still recommends testing every individual home, since levels can vary significantly from house to house.

How much does radon mitigation cost in Portage Des Sioux?

Radon mitigation in Portage Des Sioux 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 Portage Des Sioux?

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.