Sand Mining in Western Wisconsin Overview

Introduction

Frac sand mining is the process of extracting well-rounded quartz sand from sandstone of a very particular size (425 to 212 microns). This process starts by site location; finding where these deposits exist and if they're economically viable. In order to be deemed economically viable and profitable, a deposit must have no more than 50 feet of overburden (the amount of ground to be removed in order to access the deposit) for a particular deposit and relatively easy access to water. Once the sand is extracted, it undergoes washing, sorting, drying, and is then shipped to a hydraulic oil fracking site to be used in that process.

Where in Wisconsin?

Due to the geologic history of western Wisconsin, much of the country’s frac sand is mined in Wisconsin, but there are also deposits in Minnesota, Michigan, Missouri, and in the eastern United States.

Figure 1. Quartz sandstone formations and frac sand sites in Wisconsin

Environmental and Public Health Concerns

With the excavation and processing methods associated with mining for frac sand (or really any type of mining) comes potential health risks to the workers, citizens in the area, and the environment. One of the major issues associated with frac sand mining is air pollutants, more specifically: silica. Because frac sand is comprised of almost pure quartz (SiO2), drilling, processing, and transporting the sand creates silica dust. These silica particles are then dispersed in the air and can then be inhaled by workers, nearby citizens, and nearby wildlife. This prolonged exposure to silica particles in the air can lead to silicosis.

Another issue concerned with frac sand mining is groundwater depletion and/or contamination. Due to the processing involved with frac sand mining, the operation requires a significant amount of water to wash the sand. Depending on the size, duration, and location of the operation, groundwater wells could be used and therefore, might deplete the wells used, if not contribute to lowering of the water table. This water is also sometimes mixed with chemicals for the purpose of sanitizing or further washing the sand. When the company is done with the washing/sanitizing process, the mixture is dumped and could seep into the ground water. This contamination could affect wildlife, citizens who use water from the same aquifer, and streams that are fed by that aquifer.

GIS and Frac Sand Mining

Using a geographic information system could be extremely beneficial when it comes to mining frac sand in terms of managing deposit data, modeling mine sites and geological deposits, and modeling potential environmental and public health hazards associated with this industry.

Sources

http://www.fracsandinsider.com/mmi_ConferenceDL/2013FSI/FSIThurAlan%20Bennetts%20(2).pdf

https://iisc.uiowa.edu/sites/iisc.uiowa.edu/files/project/files/assessment_of_site_suitability_for_frac_sand_mining_in_winneshiek_county_final_report.pdf

http://wcwrpc.org/frac-sand-factsheet.pdf

http://geology.com/minerals/quartz.shtml

http://www.lung.org/lung-health-and-diseases/lung-disease-lookup/silicosis/silicosis-symptoms-causes-risk.html?referrer=https://www.google.com/

HalfmoonSeminar-Exploring%20Impacts.pdf