By LeAnn R. Ralph
MENOMONIE — A retired geologist and hydrologist with the U.S. Geological Survey says Dunn County must adopt an ordinance to protect groundwater recharge areas from contamination.
Townships could also adopt ordinances to protect groundwater recharge areas, said Neil Koch, who worked as a geologist and hydrologist with the U.S. Geological Survey for 32 years and who lives in Dunn County.
Koch was the featured speaker for a Chippewa Valley Learning in Retirement program at the Rassbach Museum on March 30 entitled “Drinking Water Crisis in North Carolina, Michigan and Wisconsin.”
Koch outlined problems with drinking water in North Carolina from the hog farms, in Michigan with lead contamination of the drinking water in Flint, and the problems posed in Wisconsin by septic systems in rural housing developments and Concentrated Animal Feeding Operations (CAFOs).
After the state of Wisconsin passed the livestock siting law in 2004, the number of CAFOs doubled from 150 to more than 300 because the law severely restricts the ability of local governments to determine where factory farms are located, Koch said.
The CAFOs, which include cattle, hog and poultry operations, are located all over Wisconsin, with a concentration of cattle in the eastern part of the state in Kewaunee County, he said.
In Kewaunee County, 33 percent of the wells are contaminated, and in one year, there were 230 cases of Kewaunee County residents who were sick with acute gastrointestinal illnesses from private wells contaminated with cow manure, Koch said.
Nitrate contamination can occur near manure storage areas and in places where there is land spreading of manure, he said.
The sources for nitrate in well water are manure, fertilizer and septic systems, Koch said.
A CAFO with 2,500 cows generates the same amount of waste as a city of 410,000 people. The state Department of Natural Resources recently issued a permit for an operation that will have 14,000 cows, which will generate the equivalent in waste of two million people, he said.
Dunn County has widespread nitrate contamination of wells, revealed by a study conducted by the Dunn County Health Department in 2016, Koch said.
Nitrate is the “red flag” for groundwater contamination. If there is a high nitrate level in the groundwater, other contaminants are likely present as well, he said.
Percolation
Anything on top of the ground will move down into the groundwater in Dunn County, Koch said.
The county has 91 soil types with varying percolation rates. A high percolation rate is 10 to 20 inches per hour that will seep into the ground, while a more moderate percolation rate is five to 20 inches per hour, Koch said.
Where the percolation rate is the fastest is where there is the highest rate of groundwater contamination, so the townships and the county must act to protect the aquifer. In low percolation areas, there is higher run-off during rain events and snowmelt, but there is less contamination of the groundwater, he said.
Two townships in Dunn County, the Town of Menomonie and the Town of Dunn, have passed ordinances preventing toxic industries from locating in areas with excellent and very good recharge rates for the groundwater, Koch said.
Dunn County has only one aquifer, and in fact, the Chippewa Valley has only one aquifer. Industries say they will only contaminate the top aquifer, and people can get their drinking water for a lower aquifer, but there is only one aquifer in this area, he said.
All counties should have a map that identifies the recharge areas to help local governments and county governments to pass ordinances to protect the groundwater, Koch said.
Land-spreading sites
Koch said he asked the state Department of Natural Resources for a list of land-spreading sites for septic systems.
There are more than 400 sites in Dunn County where the DNR has issued permits for land spreading, but 150 of those sites do not meet DNR requirements for percolation of no more than six inches per hour soaking into the ground, Koch said.
People may become sick with gastrointestinal illnesses but may not realize they are getting sick from their well. Human waste, in addition to bacteria, contains viruses and pharmaceuticals, he said.
Koch noted, that to be fair, the DNR approved many of those sites before there was really good data available about percolation and recharge rates.
After contacting Dunn County, the town boards in Dunn County and state officials, no action has been taken to correct the problem, he said.
After many telephone calls, letters and e-mail messages with the DNR, officials say they are working on eliminating those sites that do not meet the percolation standards but have not yet eliminated any of them, Koch said.
Land spreading of waste from septic systems is the number one polluter of groundwater in the United States, and instead of being spread on land, the waste should be taken to municipal wastewater treatment plants, he said.
Housing developments with wells and septic systems are creating a groundwater crisis, he said.
All together, 60 percent of the recharge of the aquifer in a rural housing development is coming from septic drain field water, Koch said.
Since septic systems contain a variety of viruses, COVID (the SARS-CoV-2 virus) could be in drain field water moving into the aquifer as well, he said, noting that testing of municipal water systems has shown the SARS-CoV-2 virus to be present.
The 150 unacceptable land spreading sites in Dunn County should be eliminated, and Dunn County should ban septic systems in new rural housing developments, Koch said.
