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Report: Maiden Rock mine not a health threat

A recent air monitoring study by Wisconsin Industrial Sand Co. shows no ill effects caused by silica sand processing at its Maiden Rock facility, but some of the village’s 120 or so residents remain uneasy about the underground mine located just east of the Mississippi River.

The levels of crystalline silica measuring 4 microns in diameter or smaller — also known as PM4 — in the air near the Maiden Rock mine are “extremely low and well within the range considered to be consistent with good air quality,” according to a news release Tuesday from WISC parent company Fairmount Minerals.

The study also found that the facility does not increase the amount of PM4-sized particles in the air more than other sources such as farming, unpaved roads and construction projects.

“My first response is one of gratitude,” wrote Fred Harding, a local resident and member of the Maiden Rock Concerned Citizens group, in an email response to the R-E about the report. “It is better to know than not, and we have been asking about this since December of 2010.”

Still, Harding said he is skeptical of the study, including the number and placement of monitoring devices and whether they could accurately sample finer 2.5 micron particulates identified by health experts as being hazardous.

Sampling was done at three Maiden Rock locations northeast and southwest of the facility and in the village, WISC Regional Manager Aaron Scott said. The exact spots were chosen based on predominant wind patterns.

The PM4 sampling also included smaller particulates in the 0-2.5 micron and 2.5-4 micron ranges, he said.

The monitoring program was designed with engineer John Richards and Air Control Techniques P.C., a North Carolina-based testing firm. Air Control Techniques produced the report after a year-long study.

Crystalline silica at PM4 or smaller can be dangerous if inhaled, according to a 2013 report from the Minnesota Environmental Quality Board. At that size, particulates are able to reach the lower respiratory tract and cause the lung disease silicosis.

A strand of human hair has a diameter between 50 and 70 microns in comparison.

“We will continue to manage our operations to minimize the impacts to our employees and on the environment, and to strengthen our commitment to be a good neighbor within our communities,” Fairmount Minerals Regional Underground Mine Manager Jeff Himes said in a statement.

Cooperating with WISC has been difficult in the past, Harding said, adding that it resisted years of public efforts calling for an environmental impact study on silica mining and processing.

Harding said his hope is that WISC will present the study for peer review by scientists informed on air quality issues.

Maiden Rock Concerned Citizens was formed in 2010 by residents of Maiden Rock and surrounding communities to oppose expansion of the WISC facility. The group has 241 members.

Fairmount Minerals purchased the mine in 1996 and started major upgrades in 2011, the company says. The facility produces around 1 million tons of sand per year, much of it used by the oil and gas industry for hydraulic fracturing. 

Michael Brun

Michael Brun joined RiverTown Multimedia at the Red Wing Republican Eagle in March 2013, covering county government, health and local events.  He is a graduate of the University of Wisconsin-River Falls journalism program.

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