The presence of sand highly suitable for fracking is “amazingly consistent” at sample locations in the northeast corner of Winneshiek County, according to Dr. Emily Finzel.
The assistant professor in the University of Iowa’s Department of Earth and Environmental Sciences and a colleague gave a presentation – “St. Peter sandstone in Winneshiek County: Subsurface Geology and Suitability for Mining” -- via videoconference during the Winneshiek County Board of Supervisors’ meeting Monday afternoon.
As part of a two-year partnership between Winneshiek County and the University of Iowa Initiative for Sustainable Communities, students and faculty across six different departments at the University of Iowa are undertaking extensive research on the potential impact of frac-sand mining in Winneshiek County.
Finzel presented preliminary results of analyses conducted to determine the suitability of the St. Peter sandstone from Winneshiek County as a potential source for frac sand.
Finzel’s colleague, Austen Smith, discussed findings on the depth, thickness and location of St. Peter sandstone throughout the county. He is a Master of Science candidate in the University’s Department of Mechanical and Industrial Engineering. He also is a graduate trainee in the University’s Geoinformatics for Environmental and Energy Modeling and Prediction (GEEMaP) program.
In June of 2013, the Winneshiek County Board of Supervisors established an 18-month moratorium on frac-sand mining that was to have expired Dec. 3, 2014. At the end of September, the Board extended the moratorium to Oct. 15, 2015, to allow the Iowa Initiative for Sustainable Communities enough time to finish and compile the results of their studies.

Hesper, Highland
Smith applied a statistical interpolation approach to well drilling and outcrop geology data from Iowa’s GeoSam database to estimate the upper and lower elevation of the St. Peter sandstone at all points throughout the county.
Under Finzel’s direction, Supervisor Dean Thompson and former Supervisor Dennis Karlsbroten collected hard sandstone samples from 11 locations in Hesper and Highland townships late last year to assist the study.
Smith showed a map of the county, with the northeast corner in red, where the sand is less than 50 feet from the surface and where companies might be interested in mining since its not feasible to mine when the sand is deeper.
Finzel said samples of Winneshiek County sand are in the 40/70-size class. A coarser 20/40-size class is used in places such as the oil fields in North Dakota, but the 40/70 finer class is used in fracking for natural gas, she said.
Winneshiek County sand is also smooth and round, other desirable qualities for frac sand, Finzel said.
“It’s really good, high quality for frac-sand mining,” she said.

Science is there
“The Board instituted a moratorium to study the possibility of industrial frac sand mining and to consider possible effects on public health, safety and welfare. That’s what we’ve done with the help of the University of Iowa,” Thompson said after Monday’s Board meeting.
“Recent U of I analyses of St. Peter sandstone in northeast Winneshiek County indicate the sand is highly suitable for use as frac sand. That does not mean industrial frac sand mining of the St. Peter is certain to occur in our county. Much depends on the future market for frac sand and the costs of mining and transportation.
“But technologies and markets change. It would require a failure of imagination to conclude that industrial frac-sand mining won’t happen in the future. You can’t prove a negative,” Thompson said.

What’s next?
Thompson said this semester the Initiative for Sustainable Communities will be conducting a study of the county’s infrastructure, including roads and bridges, to determine the impact concentrated truck traffic would have if one or more industrial silica sand mines were developed in the northeast part of the county.
The study will take into account the characteristics of the roads in that part of the county, including the age and type of hard-surfaced roads.
Based on mining done in other places, the study will be able to “monetize” the damage hauling sand on local roads would have, Thompson said. From the northeast corner of Winneshiek County, Smith said it would be fastest to truck sand through Allamakee County to the railroad along the Mississippi River for transport to its final destination for fracking
While Minnesota and Wisconsin have a way to seek compensation for road damages, Thompson said local officials aren’t sure they have the same type of authority.
“If we can’t find a means to seek compensation for the damage to roads, that falls back to the property taxpayers,” Thompson said.
The final report from the Sustainable Communities Initiative, including the result of economic and engineering studies, will be presented to the community in person, likely in early in May, Thompson said.