My response in the thread:
From this article, I learned:
As of January 2019, the quarry was producing gravel, limestone, and sand. Fracking was mentioned as a future venture with a potential 700 tons of product as well. Any expansions or changes in program such as these would have required an entirely separate set of permits and new conversations. The pit is estimated to have at least another 15 years of material production within it. There are 5 to 6 years’ worth of sand and gravel within the pit and 15 years’ worth of limestone. A layer of silica exists below the other material, but no contract to harvest it was in place. When the lifetime of the quarry has expired, reclamation of the land, per a plan filed with Polk County, is supposed to occur.
As of June 2019, they were mining at deeper levels for silica sand, possibly without necessary permits for the new mining for the new material. I found another article provided by a group called St. Croix River Communities Against Frac Sand Mining: The new permit allows mining to approximately 80 feet below the surface. They are permitted to place temporary concrete and hot mix plants on the site. The only controls on the mine’s activities is a 6-foot buffer zone along their property lines, an annual submission of water samples to the Board, and a requirement that new equipment shall be converted to white noise backup alarms. Under prior owners, blasts caused a couple of wells to collapse at homes along Ridge Road. The owners were never compensated for the cost of new wells.
As of January 2020, according to this article, the township put a moratorium on new permits while they do more research. This halted an attempted expansion beyond the current 80 acres that would have included 200 new acres.
I'm not able to figure out from East Farmington township's meeting notes whether new permits were issued after January 2020. I'm also going to check records for Polk County.
This article has some very suspect information shared by the mine operator. The mine sits atop a bluff that's a half mile from the St. Croix River, and there are wells and crops next to the property line, so water monitoring should be a big concern here.
“They talk about water quality,” said Torgerson, “We’re internally drained. No water can go off the site. We are highly regulated by the DNR. The permit we had to get is called the Industrial Sands Permit. … The DNR goes through a process to make sure we meet all the criteria. Flocculants have to be approved. There’s one chemical we use to wash silica sand. It’s the same flocculent that was used in building the bridge over the St. Croix River because it was a safe flocculent. They approved it.”