Radon Mitigation in Spring Valley, MN
Radon testing and mitigation in Spring Valley.
Spring Valley sits in some of the most studied karst landscape in Minnesota. The town is a few miles from Niagara Cave, and sinkholes are mapped throughout the surrounding townships. For homeowners here, the geology is not abstract.
Karst country
Niagara Cave, six miles southwest of town, is one of the largest commercial caves in the upper Midwest. The cave system, the surrounding sinkholes, and the limestone bluffs along the south branch of the Root River are all part of the same geological story. The rock under Spring Valley homes is the same rock that the cave is carved out of.
For a basement, that geology means that soil gas doesn't move evenly through a uniform soil column the way it does in most of Olmsted County. It finds whatever crack, seam, or fill channel offers the easiest path upward. Two homes a quarter mile apart can sit on noticeably different ground.
The housing in Spring Valley runs from late-1800s homes near the downtown grid to mid-century ranches further out, with rural homes on acreage across the surrounding townships. Each kind of property brings its own set of foundation conditions.
Spring Valley at a glance
Radon work in the heart of Minnesota karst country, where the ground itself is part of the picture.
- Housing
- Older central blocks with mixed-era housing from the late 1800s through the mid-1900s, plus surrounding township properties on rural acreage.
- Geology
- High sinkhole density and shallow limestone, with mapped karst features across Fillmore County and active sinkhole formation documented by the Minnesota Geological Survey.
- Median radon (Spring Valley)
- 5.6 pCi/L , above the EPA action level 23 tests/yr avg, MDH 2014–2023
- Fillmore County ≥ 4 pCi/L
- 54.9% of tested homes Ranks #31 of 87 MN counties
- Distance from Rochester
- 32 miles south
- County
- Fillmore
- Defining feature
- Karst country and Niagara Cave
What the radon numbers actually say in Spring Valley
Across the testing the Minnesota Department of Health, Radon Testing public dataset has on file for Spring Valley (2014–2023), the median home reads 5.6 pCi/L. That is above the EPA action level of 4 pCi/L. The geometric mean comes in at 5 pCi/L. That is a log-scale average that tends to track better when the distribution has a long upper tail, which radon distributions always do.
Zoom out to Fillmore County. 54.9% of tested homes in the county come back at or above 4 pCi/L. That ranks Fillmore County #31 of 87 Minnesota counties for the share of homes above the action level. A separate 73.7% of tested homes are at or above 2 pCi/L, which is the threshold the Minnesota Department of Health uses when it recommends action.
About 23 Spring Valley homes get tested every year on average, drawing from a stock of roughly 1,759 housing units. The number above is not a forecast for your specific home. Radon varies house to house even on the same street. The number is a reasonable starting line for the conversation, not a prediction. See the full data set for the by-county and by-tract picture.
Three steps. On your timeline.
Measure your radon level.
We start with a measurement of what is actually in the air your family breathes. You see the result we see, and we walk through what it means in plain language.
You see the picture first.
Once you have the result, we talk through what your home is dealing with. No scripts, no pressure. You decide what to do next on your own timeline.
A conversation about your home.
If you want to take action, we look at the basement together and talk through what a plan for your foundation could look like. Every home is its own conversation.
Other towns we cover.
Preston
Preston is the county seat of Fillmore County and home to the National Trout Center. The town is built into the bluffs along the Root River, and the terrain here is more dramatic than anywhere else in the region. The geology that drives the trout fishing also shapes what's happening under the homes.
Chatfield
Chatfield straddles the line between Fillmore and Olmsted counties, with most of the city in Fillmore. The downtown core is one of the most intact small-town main streets in this part of Minnesota, and the housing around it covers eight decades of construction.
Stewartville
The median construction year for a Stewartville home is 1987, which means the housing here splits roughly in half between older central blocks and newer subdivisions on the edges. The radon question is the same one either way, but the basement it lives in looks very different.
Find out your radon levels with a free radon test.
About 42% of tested Olmsted County homes come back above the EPA action level. The surrounding counties are higher. The first step is knowing where yours sits, and that is the part we do for free.