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The city of Viroqua is considering a proposal to participate in a geological study to look at what kind of impact the local "karst" geology may be having on water quality.

The proposal has grown out of the county comprehensive planning process being led by former county board member Lynn Chakoian.

Chakoian said issues discussed in the land use planning portion of developing the plan have raised concerns over ground water contamination. Chakoian attended a Viroqua City Council "committee of the whole" meeting last week that discussed the possibility of conducting a small-scale local geologic study.

Chakoian was joined in the meeting with Kelvin Rodolfo, retired professor of earth and environmental sciences at the University of Illinois. Chakoian said she began thinking about a study when she began to study maps of area wells that have shown evidence of contamination.

"This map is really what got my attention," Chakoian said. "It was concerning, because between Westby and Viroqua there are quite a few contaminated wells." Chakoian said there are wells with high nitrate levels, some that have been contaminated with atrazine and some municipal wells that have been abandoned.

"Its all very concerning," Chakoian said. "There are a lot of private wells out there that are having problems. I am thinking we need to get a handle on what we have out here."

Chakoian said the study being considered would be on a smaller scale with the idea in mind that it could be scaled up to a larger study at a later time if it was needed.

"If we start small with baby steps, that is the idea," Chakoian said.

Chakoian said the information gathered so far is from data sources like well drilling documentation, DNR statistics and interviews with residents.

Rodolfo said he has contacts with experts in the geology field and has been in contact with someone with the University of Nebraska that uses "electrical resistivity" to map underground rock formations. Rodolfo said he is working on having that person come to the area and do some analysis.

Rodolfo said the method is fairly new and uses electrical current to search for rock formations and especially vertical faults. Rodolfo said the research involves placing an electrical current in the ground and picking up the current along a line up to 400 yards long. By measuring electrical resistance from point to point faults can be picked up and mapped, Rodolfo said.

Vertical faults are places that contamination can reach groundwater quickly, Rodolfo said. A study of karst geology in southeast Minnesota revealed a very fractured geology. Rodolfo said usually groundwater travel is measured in inches or feet a day.

"There some areas in that study that showed groundwater traveling up to 800 feet in a day," said Rodolfo. "What that means is that if you pollute, the pollution goes like wildfire. That is sort of bad news here because the geology is the same."

Rodolfo said there are other things that can be done to better understand local geology. Local karst features, like disappearing streams, springs, sink holes, day valleys and caves can be mapped, Rodolfo said.

There are two major sandstone layers that are normally used for well drilling and water sources, Rodolfo said. One layer is known as the Prairie du Chien and another deeper layer known as the Jordan.

"You hear people say, 'I will get good water if I go down to the Jordan sandstone,' but that is not necessarily true, there has been contamination on the Jordan, too," Rodolfo said.

Chakoian said she was bringing the information to the council first for information, but also to see if there is any interest in taking the first "baby step" of a small study.

"If so, then we could come back with what a plan would look like," Chakoian said.

"So, why isn't the DNR doing this?" Alderman Marc Polsean said.

"It is always a good idea to have more and better information," city administrator Jeff Gohlke said. "It is better we know what is going on rather than waking up one day and the DNR walks in and says you have to do this and this and this without any thought of what the cost might be. If we know the road we are traveling at least we can control the expenses to some extent."

Rodolfo and Chakoian said the cost should be little or nothing to do the preliminary study and they would charge nothing for their involvement. Rodolfo said he would like to use local high school students to help gather data to keep the costs down and has offered to house some of the graduate students and geology experts that have offered to come here to conduct the study. Chakoian said she would like to approach other communities to see there is any interest in supporting the study.

"I think the whole idea is to be proactive because reacting to polluted groundwater is a losing proposition," Chakoian said.