Now we know sinkholes can create serious risks to our water supply
Monday, May 13, 2013 9:50 AM
The sinkhole was the best part of Fountain's schoolyard in the 1950s. Maybe 40-feet across and 30-feet deep - in autumn it offered shaded paths among established trees until the leaves fell. In winter it gave us packed sliding runs. The high school boys on the second floor got cardboard from Drury's and slid down several at a time. If we little kids could salvage their scraps, we used them; otherwise we just sat down and slid in our snow pants - to Mother's dismay. Those springs long ago, we engineered miniature dams and diversion ditches to redirect meltwater and sent brown leaves or twigs over rapids and around curves we designed.
Our annual school picnics were held in the tiny park across County Road 8. It had a smaller sinkhole with tree-shaded paths and gooseberry bushes for playing hide-and-seek.
Everyone we knew had sinkholes on their property. They were no good for farming, so they were used as dumps. Sinkholes were used to dispose of all kinds of waste: brush, burn piles, waste oil, old machinery, dead animals, vehicles and batteries, household sewage, surplus farm chemicals like arsenic and DDT.
We didn't know better, but we do now.
In 1966, I was in a University of Minnesota study about arsenic in well water of southeast Minnesota.
It wasn't until I was a parent that I learned from the Department of Natural Resources information by the bike trail sinkhole on the west edge of Fountain about karst geology, why we have sinkholes, and how our surface and groundwater are often the same - and vulnerable to long-term contamination.
Dye studies for tracing underground rivers showed surprising results about our fragile and active karst geology. We can't take it or our water supply for granted. We can't pretend that if sinkholes happen, we can simply fill them in and continue as before. Our challenge now is to work with the realities of protecting our aquifer in karst country.
The Rein frac sand expansion EAW acknowledges that their mining "will increase the potential [of sinkhole formation]" but assures us that "sinkholes can be easily mitigated."
Our officials are responsible for the health, safety and wellbeing of the general public. We are all responsible for a healthy, sustainable future for our young ones. Our Planning and Zoning Commission must see that conditions are put on the Rein permit that protect our precious water into the future.
Bonita A. Underbakke,