I learned a few things at the public hearing on frac sand mining held in La Crescent March 19 and was left wondering about some others.

The geologist, Dale Setterholm, said some of the best sand for hydraulic fracturing (silica sand) comes from our region and the highest quality sand is found in the Jordan sandstone formation.

According to the "Soil Survey of Houston County" issued by the Department of Agriculture, "This formation furnishes water to the towns of Caledonia and Spring Grove."

Setterholm added that silica sand mining has been going on for about a hundred years but at nowhere near the scale that is now being proposed.

DNR hydrologist Jeff Green said there are currently no legal requirements that miners take measures to prevent agricultural pollutants such as herbicides and pesticides from washing into mines. Could mines act like open wounds on the land giving these chemicals access to the now exposed Jordan sandstone formation?

You may be unfortunate enough to live near a sand washing operation that uses chemicals considered to be neurotoxins, or by a mine that has to "dewater" the pit in order to bring the water table down.

Both of these operations go through a tremendous amount of water and a lowered water table could cause wells to dry up. Green said the DNR would help with inspections and mediation, but the mining operation could be let off the hook if it's determined the well is "old."

What constitutes old? It's my understanding that if a well is in the Jordan aquifer it is, by definition, "old."

Green also said that silica sand mining has the potential to warm trout streams to a degree the fish can't tolerate.

The roads specialist, Dr. James Wilde, said that a typical Houston County road is designed to have 50,000 trucks pass over it in its entire lifetime and noted that the expected increase in traffic, once frac sand mining is up and running, could "consume" a new road "in less than five years."

Anyone driving around Houston County knows that many of these roads are already well into their expected lifetimes. Perhaps someone from the Economic Development Authority and a real estate appraiser should have been on hand to explain the effect frac sand mining would have on tourism and property values?

I came away from the meeting thinking there's way too much we don't know about what impact frac sand mining will have on the county and its citizens. And most of what we do know isn't good.

The next informational hearing should include a psychologist and an ethicist to explain why anyone who isn't starving would subject his or her neighbors and, indeed the entire county, to this potential for harm?

Michael Fields