Sand Mining in Western Wisconsin: An Overview

Despite becoming highly publicized in the last few years, sand mining has been occurring in the state of Wisconsin for over 100 years. In recent years though it has become increasingly popular for its use in the petroleum industry in a process called hydrofracking. Hydrofracking is a method of extracting natural gas and crude oil from rock across the country. Wisconsin contains quality frac sand, or silica sand, however mining for it has other environmental implications. 

Frac sand is in high demand because of its unique grain shape and size which then is suspended in a fluid substance which is then injected into the ground at high pressure into gas and oil wells. The high pressure of the fluid then enlarges fractures in the rock and opens them up to release natural gas and oil trapped within the rock where the wells cannot get to. 

(Fig. 1) Mining process using frac sand and horizontal drilling techniques.

Not all silica sands are used in the process of hydrofracking because the industry specifications are so specific. For instance, the frac sand needs to be almost purely quartz, well rounded and be very strong against compression (Fig. 2).  The major areas which this sand can be found are in regions of western Wisconsin including Burnett and Chippewa Counties, as well as Trempealeau, Jackson and Monroe counties.

(Fig. 2) This image shows frac sand and is shown to scale alongside a dime.

There are typically about seven stages in the process of the frac sand mining operation which include: overburden removal, excavation, blasting, crushing, processing, transportation and reclamation.Before the actual mining begins the overburden must be removed from the top of the sand formation at the site. Overburden is the portion of the soil which is not desired and must be removed prior to extraction of the frac sand product. Next, excavation and blasting begins in order to break apart the very heavily cemented sandstone. During this process locals can be disrupted by the noise and dust. Once the blasting is done the larger blocks of sandstone are moved to another site and broken into smaller grains. These grains are then processed into a uniform size. The processed frac sand is then transported to facturing sites around the country. There are extensive regulations depending on the location.

(Fig. 3) Locations of frac sand mines in the state of Wisconsin are represented by the red squares, while the sandstone formations are shown in gold.

Throughout this course we will be exploring the various controversial issues concerning frac sand mining. It is important to understand the risk of sand mining in western Wisconsin and sustainability. While frac sand mining can really boost local economy it can also have negative effects on the environment. These mining operations offer jobs for locals there have also been links to causing negative health effects to employees and locals because of the dust produced during the mining process. By the end of the semester we hope to have a better idea of how to incorporate sustainable practices throughout the known mines in Wisconsin. 

Sources

• http://wcwrpc.org/frac-sand-factsheet.pdf 
• http://dnr.wi.gov/topic/Mines/documents/SilicaSandMiningFinal.pdf 
• http://www.propublica.org/special/hydraulic-fracturing-national
• http://wisconsinsand.org/assets/downloads/Econ-Impact-in-Wood-County.pdf