Sand mines have been part of the Minnesota landscape for more than a century. Used mostly in the glass and construction industries, the sand mines have been an accepted part of the economy.

But that was before “fracking” became a household word.

Southeastern Minnesota contains some of the nation’s deepest deposits of silica sand, which is used to extract fuel and gas from underground rock in the process known as hydraulic fracturing. Fueled largely by the boom in oil and gas drilling in North Dakota and Montana, the frac sand market has doubled since 2008, according to the U.S. Geological Survey. The local silica deposits are creating an anticipated gold rush with the dual benefit of creating local jobs and helping America become energy-independent.

So why not jump on the demand for silica sand? As is often the cases with mining, there are many unanswered questions about health and environmental costs.

Silica is a known carcinogen, although the Minnesota Pollution Control Agency says most of its information on silica’s health effects comes “almost exclusively from occupational settings, where exposures are more concentrated. There are no federal or state standards for silica in ambient air.”

Many residents object to the noise and truck traffic caused by the mining. Environmentalists worry about the damage to the region’s hills and bluffs and the potential water and air pollution.

That’s why several counties, cities and townships have adopted silica sand moratoriums to sort out these issues to allow local officials time to update their ordinances.

Here’s a sample of the varying moratoriums throughout the region:

• Winona County’s moratorium expired in May.

• The city of Winona has extended its moratorium until March 2013.

• Goodhue County’s moratorium will expire in September 2012.

• Fillmore and Houston counties’ moratorium will expire in February 2013.

• Wabasha County’s moratorium was recently extended to August 2013.

• Olmsted County hasn’t enacted a moratorium, but a proposed silica mine near Chatfield put county officials on alert. Olmsted officials toured a silica mine in Blair, Wis., on Friday before considering an updated transportation ordinance later this summer.

It was a welcome development when four state agencies — Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, Minnesota Department of Health and Minnesota Department of Transportation — recently sent representatives to a meeting in Winona to discuss the health and environmental concerns related to silica mining.

“It’s really important because what we’re trying to do is identify any gaps between the city (or county) regulations and state code,” said Carlos Espinosa, the assistant city planner in Winona, who organized the June 20 meeting.

There’s little doubt that silica sand mining will embed itself into the regional economy, but there will be some bumps in the road. While we applaud counties for “tapping the brakes” on sand mining and shipping as they form committees and do their own research, we’re troubled by the idea of a patchwork, piecemeal approach to regulating this growing industry.

The state needs to get involved, providing counties with the unbiased information about the ambient risks of silica and solid recommendations on how it can be safely mined and transported.

— Rochester Post-Bulletin, July 2