A frac sand mine in western Wisconsin was shut down earlier this month because it lacked a permit to operate. As one of 135 similar mines in Wisconsin which have appeared throughout the state in the past few years, these mines are walking a fine line between controversy and economic growth.

These mines are becoming increasingly prevalent throughout Wisconsin as hydrofracking becomes more popular nationwide. University of Wisconsin geological engineering professor Craig Benson said the state has a high prevalence of silica sand, which is necessary for fracking sites in other parts of the country.

“We have these wonderful sandstone deposits which have really well-rounded, hard, uniformly-sized sand particles,” said. “They’re a jewel for frac sands and we just have lots of them, geologically, particularly in the western half of the state.”

Benson said these types of silica sands are unique to this part of the country and are useful in hydrofracking because they hold open the cracks in bore holes of fracking sites better than normal sands. This has made Wisconsin’s silica sands highly profitable in recent years, he said.

But this profitability comes with a cost, Stacy Harbaugh, Communications and Outreach coordinator of Midwest Environmental Advocates said. She said people have concerns about the impact on health and the health of the environment in places nearby frac sand mines and links found between silica dust and cancer.

“People are calling it the new strip mining because it takes out a large surface area in places these mines are located,” Harbaugh said.

Harbaugh said frac sand mining is changing the landscape of these regions of Wisconsin, and not in a good way. She said there are negative impacts when soil is disturbed on a grand scale and the large loss of trees has created issues with pollution due to storm water runoff.

Benson said there were issues regarding what frac sand mines do to the environment and the health issues they cause to people who live and work in and around them. But he also said the mines have created jobs in parts of the state that really needed them and the rising price of these sands has been great for miners and the state’s economy.

This conflict was a feature of Friday’s gubernatorial debate. Both candidates expressed concern about mines, like the site which was shut down in Trempealeau County, that are operating without proper licensure.

Gov. Scott Walker said “thanks to God and the glaciers, we have some of the best frac sands in the world,” in the gubernatorial debate, adding that he would like to continue the economic growth from these mines. He also said he would try to do more in the future to add regulation positions to keep the mines operating legally.

Burke, however, expressed concerns over balancing job creation and defending natural resources. She said she would do what she could to give power to the local communities so they could make decisions on frac sand mines instead of “big-money special interests” controlling the process.