Sifting Through Sand Mining
By Brook Lenker and Ted Auch, FracTracker Alliance
Thirty miles northwest of Eau Claire, Wisconsin the land rolls gently. Wooded hills back orderly farms straight from the world of Norman Rockwell but painted red and gold by October’s cool brush. It seems like agrarian perfection, but the harmony is interrupted by the pits and mounds of a newcomer to America’s Dairyland – sand extraction to support hydraulic fracturing for the oil and natural gas industry.
“Mine, Baby, Mine” reads a bumper sticker on a pickup outside the Baron drying plant of Superior Silica Sands – a frac sand company headquartered in Fort Worth, Texas but with significant activities located in Wisconsin. Ted Auch, Ohio Program Coordinator for FracTracker, and I are on a daylong sand mining tour organized by the West Central Wisconsin Regional Planning Commission (WCWRPC). This, the second Superior drying plant we visited, processes up to 2.4 million tons of sand per year (enough sand to complete 800 typical horizontal gas or oil wells). This is among the largest facilities of its kind in the world.
What is frac sand?
Frac sands (99% silicon dioxide – SiO2) are meant to “prop” open the rock after fracturing is complete, termed “proppants.” Aside from water, these sands represent the second largest constituent pumped into a typical well to hydraulically fracture the shale. Usage of frac sand as a proppant is increasing due to the rising costs associated with synthetic substitutes like ceramic and related resin-coated materials. Ideally, such sand must be uniformly fine and spherical, crush-resistant, acid soluble, mature, and clay/silt-free. The northern Great Lakes Basin represents the primary stock for high quality frac sand in the world – causing many industry analysts to label the region Sand Arabia.
And where does it come from?
Most of Superior’s total production (4.2 million tons per year) comes from mines in New Auburn and Clinton, Wisconsin – in the middle of the St. Peter (Ottawa) Sandstone. This formation underlies parts of Iowa, Wisconsin, Minnesota, Illinois and Missouri. Known for its uniform and rounded grains – the region has recently surpassed the Hickory (Brady) formation in Texas, which contains sands that are far more angular, blocky and coarse.
To get an idea of the landscape where these sand mining operations are occurring in Wisconsin, see Figure 1 below.
Figure 1. Land cover types (%) and the location of the mines we visited during our recent frac sands tour of West Central Wisconsin (Note: 1.0 = 100%)
“Thank God for Superior Silica Sands,” said Jim Walker, Director of Operations. He wasn’t directly touting his employer’s virtues, but rather sharing a quote from a landowner pleased with the income derived from leasing their farm for the sand beneath. According to Walker, Superior has over 100,000 acres of mining leases in Wisconsin – enough to support their company’s anticipated needs for the next 30 years. Based on frac sand mine permitting data provided to us by the planning commission, this 100,000 acreage translates to 939,700,000 tons of frac sand (enough for 313,233 horizontal wells). Overall, Wisconsin’s frac sand mines are currently producing 185-211 million tons of frac sand from 128 facilities.
Superior is one of more than six sand companies working in the area. One state resident recently emailed me complaining that “we are being inundated with industrial sand mining.” Her perspective is one of concern, but we are told of farmers who are eager to lease their land for potentially hundreds of thousands of dollars in annual payments. Superior prides itself on hiring from the community. The jobs pay well, nearly twice the regional average, according to the planning commission. Healthcare benefits and a 401k are included. At quick glance, it is an economic boom to a rural region, but will it last? Superior has a 10-year contract to supply sand to Schlumberger, a giant in hydraulic fracturing services. Sand prices – affected by competition and overproduction – are dropping, however.
Sand Mining Risks
Environmental impacts may be the biggest cause for worry. Some mining operations can cover more than 450 acres and often involve the destruction of forests. This may happen piecemeal, perhaps 20 acres at a time, but forest habitat and the associated functions (e.g. carbon storage and accrual) are nevertheless diminished. The land is remediated1, but the landowner makes the decisions as to how this occurs. They might choose to plant prairie grasses or trees, but a common preference is more cropland – the latter option enabled by a post-mining reduction in topography. Adaptable wildlife like deer may take the changes in stride, but forest-dependent species and vulnerable plant communities will likely suffer. Water quality and quantity issues have also been highlighted by Wisconsin Watch, Minneapolis Star Tribune, and Minnesota Public Radio.
Public health impacts are perhaps less clear. Superior officials explain that only the finest sand sizes are a legitimate inhalation hazard, and those are atypical to the frac sand industry. A 2012 OSHA hazard alert, however, listed respirable crystalline silica as a significant workplace hazard on unconventional oil and gas well pads, just behind the risk for physical injuries and hydrogen sulfide exposure. At least at Superior, they rigorously monitor the air quality onsite and outside their boundaries. Employees are even monitored for what they breathe. Superior shows data underscoring its outstanding safety and regulatory compliance record. I observe no noticeable blowing of sand or dust on site. While I am on the ground touring, however, Ted enjoys a bird’s eye view courtesy of LightHawk. From the plane, he witnesses aerial movement of material off of other sand mines.
Emissions from increased truck traffic may also present an air quality concern. Dump trucks ply the back roads like worker ants delivering load after heavy load from the mines to the drying plants. The general increase in activity in these forgotten areas may be a lifesaver for some, and a worry for others. Trains with scores of covered, sand-packed cars rumble down the tracks bound for distant shale basins. Texas awaits the trains departing Superior’s Baron plant. Meanwhile, communities express concern about increasing speeds and the safety of crossings.
A Complicated Perspective
For me, the day’s enlightening dialogue and experiences underscore the rough, expanding tendrils of unconventional oil and gas development. They reach far and have complex, often abrasive effects. Here, in the land of Leopold, the father of the Land Ethic, I can’t help but wonder: What would Aldo say about the transformation of his beloved countryside?
For additional resources and articles on sand mining issues, visit the Land Stewardship Project in Minnesota and Wisconsin Watch.
 Reclamation success, permitting, bond release, inspection and enforcement, and land restrictions were put into law by the Carter administration and introduced by Arizona Republican Morris Udall as defined by the Surface Mining Control and Reclamation Act of 1977, which also created the Office of Surface Mining.
i am gnan kumar from india, want to know from you that
1. do you produce sand from sandstone mines by crushing them or not?
2. if, yes, what are the required physical and chemical propeties of the mines to be suitable for producing sand from ?
pls give me the reply.
The FracTracker Alliance is not in the sand mining business. Apparently though, the sands that are in demand are well-sorted, fine grained, rounded, and with a high silica content.
Great point Bruce. Indeed 1.0 = 100% I just edited the post to reflect your inquiry.
As for the the sandstone comment we know that the surface sandstone geology polygons for the Great Lakes are well correlated with current fracsand mining operations. This stuff is loosely aggregated and near or at the surface more often than not. Sand and sandstone essentially part and parcel at this level of analysis.
See presentation on mechanics and protocol from industry here
And Wisconsin sandstone geologies
The captions for the maps say they are in %, but the legends seem to be in decimal form… Is “1.0” in forest cover map legend 1% or 100%?
Also, the article kind of implies that these are sandstone mines? The article says the mines are “in the middle of the St. Peter (Ottawa) Sandstone… formation.” Do they mine and crush the sandstone, or do they mine sand?