Demand for frac sand appears to be plateauing. There's too much of the hard round sand right now, some western Wisconsin operations and one Minnesota facility are idling, and new construction has pretty much stopped, the Winona Daily News reports this week.

"There's simply more sand available than the industry needs at the moment," the story says. "Some of the region's newly permitted sand mines are idle, as are loading and hauling facilities, and some operations are stockpiling sand."

The piece cites U.S. Silica, the second-biggest silica company in the country, saying supply has pretty much reached a balance with demand, and points to the idling of a new facility in Wabasha, Minn.

This is pretty big news for Wisconsin, Minnesota and the big railroads that serve North Dakota through the Twin Cities. It should also be notable for opponents of frac sand mining.

The sand is shot into the ground to hold open rock that's split open by hydraulic fracturing to get at oil and natural gas reserves. The method is used in Texas, North Dakota and the Northeast, and has driven a U.S. energy boom that is shifting the global energy map. (The process is new enough that the environmental impacts aren't clear, though methane emissions and possible effects on drinking water are consistently-raised and much-debated concerns.)

The best sand for fracking is widely available in western Wisconsin and southeastern Minnesota. Wisconsin has an overnight sand industry that's created some economic activity and provoked a lot of opposition, railroads have a new line of business and have done some modest expansion, and Minnesota has pondered frac sand mining but it hasn't really taken off here yet.

Apart from general opposition to fracking, there is heavy opposition to sand mining in both states for the way it can allow wet sand and wastewater to discharge into streams, for using a lot of water to clean the sand, for the noise and hassle of the trucks and the fine dust that drifts up into the air. The Star Tribune has done a thorough job of documenting these concerns here, here, here and here, among many others.

Now we have the prospect of there being no need for Minnesotans to fight frac sand at all.

That's not to say that Wisconsin's mines will close, but if supply is outpacing demand, one would think the chances of a sand mining proliferation in southeastern Minnnesota are getting slimmer. It could be that the market has already played itself out.

(Photo: Brian Peterson, Star Tribune, March 2012. Caption: The Biesanz Stone Company is the only existing sand mine in Winona County. It is experimenting with frac sand mining.)