WISCONSIN'S INDUSTRIAL SAND RESOURCE AND THE GROWTH OF THE FRAC SAND INDUSTRY, 2008–2014

In 2008 Wisconsin ranked third in production of industrial sand, with less than ten active sand mines. In 2014 Wisconsin ranked first, with more than 100 mines and processing facilities operating or in the planning stage. In that time period the share of U.S. sand production used in hydraulic fracturing increased from 15% to 72% as horizontal drilling technology was applied to shale oil and gas drilling. Western Wisconsin became the center of frac sand mining because of ideal geology. The Cambrian Mt.Simon, Wonewoc , and Jordan Formations, and the Ordovician St.Peter Formation are composed of monocrystalline quartz grains that are well rounded, highly spherical, and have a high compressive strength, qualities essential for use as frac sand. Western Wisconsin is within the classic Driftless Area, and all of these sandstones are easily accessible for mining.

The Mt. Simon has not been extensively developed due to shaly and silty beds and thickness is limited by erosion. Most Wisconsin sand is produced from the Wonewoc which is well exposed and has ideal gradation and physical properties. Access to the Jordan is limited by the ubiquitous cap of Prairie du Chien carbonates, making underground mining the preferred option in Wisconsin. The St Peter has a finer median grain size than the Cambrian sands. It is not mined for frac sand in the west, but is an important source of foundry sand in Eastern Wisconsin.

The quality and extent of the resource will insure Wisconsin’s future as a leading sand state. The rapid growth of the industry has raised environmental and land use issues and taxed existing transportation infrastructure. The success of hydraulic fracturing has resulted in lower energy prices and a drop in drilling activity, which will impact industry growth in the short term.