ST. PAUL, Minn. (AP) — The Minnesota Supreme Court on Wednesday upheld Winona County’s ban on the mining and processing of silica sand, which is used in the oil and gas industry for hydraulic fracturing.
A divided high court affirmed a 2018 ruling from the Minnesota Court of Appeals, which rejected a challenge to the county’s 2016 ban filed by Minnesota Sands LLC. The company, which held five mining leases at issue in the case, argued that the ban was unconstitutional.
But the Supreme Court agreed 4-3 with lower court rulings that Winona County’s ordinance was constitutional. The southeastern Minnesota county imposed the ban out of concerns about the environmental and health impacts of silica mining and processing..
Parts of southern Minnesota and western Wisconsin contain rich deposits of high-quality silica sand of the ideal size, hardness and purity for hydraulic fracturing. The sand acts as ball bearings to prop open cracks in underground rock to let oil and gas flow out.
But the silica sand mining industry in the upper Midwest has struggled in recent years due to competition from cheaper sand mined closer to the oil fields of Texas and Oklahoma. While the Texas sand is of lower quality, lower transportation costs often make it more economical.