The Montana Supreme Court issued a decision that will allow the opening of the Black Butte Copper mine in Meagher County. The court declared that the Montana Department of Natural Resources and Conservation (DNRC) properly issued a permit to Tintina Montana Incorporated (now Sandfire Resources) in how it will use groundwater in mining 14 million tons of copper.

The court’s decision is the final legal barrier that stood in the way of the mine becoming operational.

The DNRC’s work and permit approval was challenged in a suit brought Trout Unlimited, Montana Environmental Information Center, Earthworks and American Rivers.  The water at issue is 250 million gallons of groundwater that the mining company is not actually using but is moving to a different location.

In a 5-2 opinion, the judges approved Tintina’s plan to remove water that it doesn’t need for its operation but is in the way– referred to as “remainder water.” It intends to treat the water on-site to remove nitrogen that can be problematic for aquatic ecosystems. They will then inject the water underground from where it will be gradually filtered into the water aquifer.

The company argued that the water is neither used nor wasted, only relocated. Water that the company uses in the mining process – about 100 million gallons — is treated differently.

The opposing environmental groups claimed that the company’s plan will diminish the quantity and quality of water in the Smith River. They claimed that the DNRC has created a “loophole” that circumvents a constitutional requirement that Montana’s water is to be “comprehensively regulated and protected.”

The justices noted that there are “manipulations” of water that don’t fall neatly within the beneficial use or waste categories. They further noted that it’s an area in which the Montana State Legislature could play an important role in determining if the situation can be better regulated.