Frac sand mines idling, so one question

When I read this story about the slowdown in frac sand mining in Minnesota and Wisconsin, and wondered who's keeping an eye out for spills, dust and erosion, this quote was not a confidence builder:

In Wisconsin, state officials count some 85 companies statewide actively mining, processing or hauling sand, and 40 inactive companies. Despite slack demand, several companies have sought permits for new or expanded sand operations in Wisconsin, said Roberta Walls, the industrial sand specialist for the Wisconsin Department of Natural Resources. 

Walls doesn’t track how many of the facilities have been idled or cut back on employment though.