Winona, Minn., got a clean bill of health from the Minnesota Pollution Control Agency (MPCA), according to its year-long study of pollutants related to diesel truck traffic and silica sand mining, according to the Winona Daily News.
The MPCA study measured data collected from January to December 2014 from an air monitor atop the Winona YMCA in downtown Winona.
The report indicated two times in 2014 that the levels of sand were detectable, but both were well below the level damage from long-term exposure.
The study compared the measurements from the Winona monitor to one placed in Stanton in Minnesota’s Goodhue County, where there are no silica sand related facilities or transportation, but other sources of airborne silica such as unpaved roads and farm fields.
Part of the reason for that control is that silica sand dust is a common pollutant and not particular to the frac sand industry.
The study was conducted over a time frame when the frac sand industry, and the amount of silica sand being moved through Winona, was at its peak. In 2015 the industry slowed to a near stop, following a drop in oil prices and demand for sand of the quality found in Minnesota