Environmental reviews of two proposed silica sand mines in Winona County are up for public comment starting Monday.
They are planned for Saratoga Township, just south of St. Charles, where a processing facility is also proposed.
Citizens groups are asking for a broader study.
Johanna Rupprecht, policy organizer for The Land Stewardship, said the projects are so closely connected that the county should do an environmental impact statement that would cover all of them.
"These mines, other mines proposed by the same company in the same area both in Winona County and just across the border in Fillmore County," she said, "and also the county needs to look at the connection between these mines and the proposed processing facility in St. Charles, which is proposed by related companies."
While some local citizens groups criticized the review process, Planning Director Jason Gilman said the process is following state rules.
Gilman said there may not be enough information to answer all environmental questions, such as how much dust trucks will raise as they haul the sand to processing plants and rail hubs.
"For those issues that we aren't able to respond to," he said, "we're going to have to indicate there isn't adequate information available on that topic, and that in itself may become a candidate for further study."
People may comment on the two environmental reviews until Jan. 23. The county will then decide whether a broader study is needed.
These projects are separate from a proposed sand transport facility planned for the Mississippi River at Wabasha.
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