Mining the sand used in fracking wells involves environmental, health, and economic issues. While scientists are studying these effects, the work continues despite the unknowns. (More)

Most people have heard of hydraulic fracturing or fracking which is the latest way to drill for oil and natural gas embedded in the layers of rock deep beneath the earth’s surface. Fracking requires a certain type of fine silica sand, a chemical cocktail and lots of water. Today we’ll get an overview of some of the issues surrounding the mining of frac sand and tomorrow we’ll look at the responses of communities and governments.

If you are thinking about a child’s sandbox or a walk along an ocean beach, Think again. Think something more like mountain top removal. This photo from the Wisconsin DNR shows a sand mine near Grantsburg, WI near the St. Croix River.

20120518_saint-croix-sand_39 has a nice primer on frac sand with more photos.

Over one million pounds of frac sand can be used to stimulate a single well.

The new fractures in the rock, propped open by the durable sand grains, form a network of pore space that allows petroleum fluids to flow out of the rock and into the well. Frac sand is known as a “proppant” because it props the fractures open.

Reported average prices for frac sand in the U.S. Geological Survey Minerals Yearbook were between $45 per ton and $50 per ton in 2010. This is significantly higher than the average price of $35 per ton for specialty sand sold outside of the construction industry.

Frac sand is currently being mined in Texas, southeast Minnesota, southwest Wisconsin and proposed for northeast Iowa. The Midwest has what’s geologically called the St. Peter sandstone formation. Underneath the farm lands and river bluffs is silica sand that is perfect for fracking. Here’s a link to a map of frac sand mining in Minnesota. And here is Wisconsin.


When frac sand first was mined in the Midwest, the existing state mining regulations did not fit precisely. In some cases, it was up to local communities and/or county governments to decide whether and/or how to proceed. Minnesota and Wisconsin have taken very different approaches. Minnesota has a Democratic legislature and governor. Wisconsin has Republicans in charge. LaCrosse, WI and Winona, MN are situated across the Mississippi River from each other. As the LaCrosse Tribune points out, in the differences we see a tale of two cities:

Doug Losee can sum up the differences between Minnesota’s and Wisconsin’s frac sand mining regulations by describing how much room the two states’ environmental studies take up in his office.

“The Minnesota files really take up a bookcase. And for the most part, Wisconsin I can fit in a filing cabinet,” said Losee, who oversees environmental regulations for Mankato-based Unimin Corp.’s sand mines in Minnesota and Wisconsin.

The thick, three-ring binders that occupy Losee’s office bookcase are filled with scoping documents, data about groundwater and hundreds of pages of public comments, all part of the environmental impact statement (EIS) required for mines of a certain size in Minnesota.

The in-depth environmental study usually isn’t required in Wisconsin. That difference is one way mining experts say the two states have taken different regulatory approaches to the growing silica sand industry.

Obviously, air and groundwater don’t recognize being on opposite sides of a state boundary or a county line. Various units of government are seeking to cooperate, coordinate and even obstruct regulations that, depending on your point of view, are either urgently needed or getting in the way of mining companies and individual landowner’s rights.

Health Risks:

Institute of Medicine of the National Academies of Science held a conference on the health impacts of fracking.

The path to lung cancers from silica dust is one of the oldest occupational health diseases on the books, and in this case completely preventable.

Eric Esswein, a Senior Industrial Hygienist for the National Institute of Occupational Safety and Health (NIOSH). Mr. Esswein presented the occupational health risks he found at 11 fracking operations in five states (CO, ND, PA, TX, and AR). The presentation was straightforward and frank. Fracking uses up to 4 million pounds of silica sand per well to prop open all the newly created fractures in the formation. The NIOSH recommended health limit is that no worker should breathe in more than 500 micrograms of that silica per day or else risk silicosis, an irreversible disease with a well-known, well-documented path to lung cancer. When Mr. Esswein placed monitors on 116 frack site workers to measure their breathing zone exposure, 79% of samples had more silica dust than recommended, 31% were 10 times higher than recommended, and the highest sample was 137 times higher than the NIOSH recommended limit.

Dr. Eula Bingham, a former Assistant Secretary of Labor from the Carter Administration, rose to comment and evoked the Gauley Bridge incident when hundreds of workers died within a few months following silica exposure.

Frac sand mining is creating the same silica dust and trucks carrying the sand are rolling through the countryside. The trucks are supposed to be covered. The sand dust from the mining sites becomes airborne and on a windy day can travel quite a ways. Although the NRDC was addressing fracking, the mining of the silica sand carries the same risks.

Groundwater Pollution:

After it is mined, the sand needs to be processed. This involves using well water to wash the sand. The water is recycled and used again. Crispin Pierce of the University of Wisconsin Eau Claire has planned a five-year study:

Frac sand mines use a lot of water – millions of gallons a month – to process the sand and keep dust down. They typically install high-capacity wells similar to those used for farm irrigation.

The project will also model how mining’s re-shaping of the landscape will affect how precipitation recharges the groundwater.

fracsand-wash-300x200From bottom right, a conveyor carries sand from the crushing area to a wash plant tower to be washed and sorted by grain size at the Preferred Sands plant in Blair, Wis., on June 20, 2012. Wash plants like this use thousands of gallons per minute, most of it recycled. Lukas Keapproth, Wisconsin Center for Investigative Journalism

If the processing water gets into the groundwater, the water needed for human consumption, animal consumption and agriculture will be contaminated. Each well applies for an individual permit. The cumulative effect of all the new wells on the groundwater is not known. The Wisconsin study will be rigorously scientific, but if its results are negative we will know only after five years of pollutants have been dumped in our groundwater.


The frac sand is moved by trucks to rail yards to be shipped to fracking sites elsewhere in the country. Wabasha, MN counts 600 to 900 loaded trucks per day arriving at their storage/shipping facility. Rural roads and bridges were not designed for this much traffic or these heavy loads. Who will pay for upgrading and maintaining the roads and bridges? Right now the answer is local property taxes in Minnesota. In Wisconsin, Gov. Scott Walker is supporting sand mining:

Walker’s budget also includes $6.4 billion worth of investments in the state’s roads, bridges and freight routes. Part of that investment is aimed at improving freight rail in Monroe County, an area of heavy frac sand mining.

Improving freight rail service is key to making sand mining profitable. While the sand itself is easy to mine, moving it by truck is both expensive and hard on local roads. has some estimates of traffic:

If mine growth continues as predicted, the state Department of Transportation estimates frac sand mines could generate nearly 20,000 truck trips a day to and from processing facilities. Those trucks are projected to fill more than 2,000 rail cars daily headed for drill sites outside of Wisconsin.

Economic Impacts:

Proponents of frac sand mining say it will create good paying jobs and it has, says Charlie Walker, president of the Chippewa County Economic Development Corporation:

“The biggest impact we’ve seen is the job creation,” Walker said. “There were 150 unemployed truck drivers in Chippewa County coming out of the great recession. Now, we have a shortage.”

In January, EOG Resources opened its sand plant, the largest in the nation, in Chippewa Falls. EOG employs about 70 people at its processing plant and 30 at the mine sites. The company also contracts with about 100 truck drivers, bringing the direct job total to about 200, Walker said.

In addition to creating jobs, sand mining operations contribute to the local tax base. According to Walker, last year EOG paid $1.4 million in property taxes to the city of Chippewa Falls.

As of July 1, the (Wisconsin Economic Development) Center found 86 mining, processing and rail loading facilities operating or in development in the state, plus an additional 20 in the proposal stage. WEDC estimates 10 jobs per frac sand mine and 50 to 80 jobs for every processing facility or combined operation.
Using the lower end estimates, these 86 facilities could employ 2,780 people, about 2,500 more than in 2008.

In rural areas with higher unemployment, a $15-20/hour job is seen as a really good thing to have. On the other hand, many of these same areas rely on the tourism dollars of hiking, biking, fishing, hunting and other recreational activities. The tourism dollars and associated jobs are threatened by the presence of the sand mines and the sand truck traffic. If one farmer leases part of his land for sand mining and the money helps save his farm, does it matter that his next door neighbor gets asthma or worse?


This represents a brief overview of the main issues associated with the mining of frac sand. Wisconsin is embracing the industry. Minnesota is attempting to balance jobs and economic development versus the environmental and health risks. Iowans are trying very hard to not have it at all.

Frac sand mining has all the classic trade-offs: business versus the environment, preserving the landscape versus exploiting its resources, jobs versus unemployment, socializing business costs versus taxpayers subsidizing profits, and the rights of an individual land owner versus the community’s wishes. Sadly many of the answers to the toughest questions will come through experience.