Here is the background to this story:

The Gros Ventre and Assiniboine Tribes reside on the Fort Belknap Indian Reservation, located in north-central Montana. Two cyanide heap-leach gold mines are located outside, but near the southern boundary of, the Fort Belknap reservation, in the Little Rocky Mountains mining district. The Little Rocky Mountains mining district is a location long used by the Gros Ventre Tribe for subsistence, social, and religious purposes. The district is also Montana’s largest gold producer. The Bureau of Land Management (“BLM”) approved the expansion of the two mines in 1996, despite the Montana Department of Lands’ conclusion that acid rock drainage from the mines had become a wide-spread environmental problem.

In 1998, the Gros Ventre Tribe appealed the expansion of the two mines to the Interior Board of Land Appeals. While the appeal was pending, the mining companies went bankrupt and announced they would abandon the expansion plans and reclaim and close the mines. [4] The BLM subsequently rescinded its expansion approval and issued a new decision requiring the reclamation of the mines.

In 2000 the Gros Ventre Tribe filed suit, claiming that the federal government breached its trust responsibility to the Gros Ventre Tribe by failing to protect the tribe’s trust resources in approving, permitting, and failing to reclaim the mines. The federal government won at the district court, and the Gros Ventre Tribe appealed.

The findings of the Ninth Circuit Court of Appeals was filed November 13, 2006. This is a summary of the finding:

The court upheld the dismissal of Native American tribes' claims against the U.S. government for authorizing the expansion of certain gold mines. Specifically, the tribes argued that the government violated its obligation to protect tribal trust resources--primarily water rights--by authorizing the creation or expansion of two cyanide heap-leach gold mines located upriver from the tribes' reservation. But because none of the statutes or treaties cited by the tribes imposed a specific duty on the government to manage non-tribal resources for their benefit, the tribes did not have a common-law claim for breach of trust. Consequently, the tribes had to rely on the Administrative Procedure Act (APA) for a private right-of-action. But the tribes' National Environmental Policy Act and Federal Land Policy and Management Act claims, subject to the APA, were either barred by statute of limitation, failed to present a "final agency action," or did not involve a controversy for which the tribes had standing to pursue. The lower court, therefore, properly dismissed their claims.

Here is how the Tribal Supreme Court Project sees this decision:

On June 14, 2007, the Gros Ventre and Assiniboine Tribes of the Fort Belknap Reservation filed a petition for cert seeking review of a decision by the U.S. Court of Appeals for the Ninth Circuit in a case that involves a breach of trust claim against the United States for permitting the operation of two cyanide heap-leach gold mines located adjacent to the Reservation that have had, and continue to have, devastating impacts on the Tribes’ water and cultural resources. According to the Ninth Circuit opinion, Tribal claims for breach of trust, which arise from the treaties signed decades ago, must be raised in the context of other federal statutes. The Ninth Circuit held that even if the federal government has a common law trust obligation that could be tied to a statutorily mandated duty, there is no affirmative duty here requiring the federal agency to regulate third parties to protect what the Court termed to be “non-Tribal” resources. The United States’ brief in opposition is due on August 20, 2007.

At this site is a link to a 2006 Final Engineering Evaluation /Cost Analysis for Water Management at the site. The file is 8 mb and takes a while to download and read, so here is an edited summary of the Executive Summary—it makes for sober reading.

The Zortman and Landusky Mines are located in north-central Montana in the Little Rocky Mountain. The mines are near the towns of Zortman and Landusky and located on a mixture of patented mining claims (private lands) and lands managed by the Bureau of Land Management (BLM). Pegasus Gold Corporation and Zortman Mining, Inc. operated the mines from 1979 through 1998, when the operator filed for bankruptcy protection. With filing of bankruptcy and exhaustion of the financial guarantees used to fund reclamation, the mines are abandoned. The BLM is the lead federal agency for conducting removal actions at the Site under its CERCLA authority. The Montana Department of Environmental Quality (DEQ) is assisting with water treatment activities at the Site according to the terms of the memorandum of understanding (MOU) entered by DEQ and BLM in August of 2004.

The purpose of this Engineering Evaluation and Cost Analysis (EE/CA) is to reassess the existing and anticipated water quality Site conditions, evaluate the performance of the current removal actions, and to assess the costs and amounts of funding available to continue or where needed, improve the water collection and treatment practices.

This EE/CA is the next step in continuing removal actions needed to protect public health, welfare, or the environment. It addresses the management of Operable Units OU1, OU2, and OU3 which treat mine drainage, treat leach pad waters, and reclaim reactive mine waste units, respectively.

The estimated annual operating and maintenance costs for the capture and treatment of mine-impacted water is $1.5 million, however, only $731,321 in annual funding is available under the near-term water treatment surety bond through year 2017. Since 1999, the BLM has provided on the average of $100,000 per year in additional funding to keep these facilities operating

because the surety bond payment is not sufficient to pay for operation of the water treatment plants for the entire year.

With completion of reclamation earthwork, overall site management and water treatment costs are projected to exceed the available funding by about $770,000 annually.

A one-time lump sum amount of approximately $8 million is required to finance the yearly shortfall of $770,000 through 2017. After 2017, the source of funding switches to two long term trust funds; a $14.6 million fund established by the mine operator in 1996; and a $19.3 million supplemental trust fund created by the State of Montana House Bill 379 in 2005 (thanks in part to Representative Jonathan Windy Boy and the Fort Belknap Reservation who sponsored and supported the Bill). As of September 2006, a source of funding to ensure water treatment for years 2008 through 2017 has not been secured.

Current Site Conditions

The existing mine drainage water treatment plants and collection systems (OU1) generally do a good job meeting primary drinking water standards, but do not always meet chronic aquatic standards at the water treatment facility discharge points. With natural attenuation, the treated water generally satisfies the DEQ-7 water quality standards before leaving the site boundary (Section 2, Figure 2).

At the Zortman Mine, the majority of the treated water seeps into the bedrock beneath Ruby Gulch and does not appear as surface water downstream of the town of Zortman except during major run-off events. The treated water does infiltrate to the Madison Formation, an important aquifer, where it outcrops in Ruby Gulch near Zortman.

Treated water from the Landusky Mine water treatment plant flows down Montana Gulch into Rock Creek where it merges with flow from other drainages. November 2005 surface water testing of the co-mingled Landusky Mine water treatment plant discharge and the biological treatment plant (OU2) discharge along Rock Creek below the Landusky Mine showed all trace metal concentrations were below the Applicable or Relevant and Appropriate

Requirements (ARARs) downstream from the town of Landusky. It is interesting to note that some of the metals, sulfates and Total Dissolved Solids begin to increase downstream of where Rock Creek crosses highway 191 after flowing across the Cretaceous age sandstones and shales. If the water presently collected and treated at the Landusky Mine were not captured and treated there would be adverse consequences to the domestic wells in Landusky, and considering the acidic condition of the major leach pads, the water quality in Rock Creek would not meet ARARs for either the human health or aquatic life standards.

The treatment of the leach pad waters in the biological treatment plant (OU2) is working well in the removal of selenium and nitrate. Co-mingling of this treated water with treated water from the Landusky Mine water treatment plant in the Montana Gulch Pond provides a discharge that generally meets ARARs where it enters Montana Gulch.

Alternatives to Current Treatment Practices

Passive Treatment - Passive or semi passive water treatment systems could be used to some degree, but pilot scale testing must occur before any informed decisions could be made regarding feasibility. The large amount of aluminum and iron present in some of the untreated water can foul passive systems. Testing would also be necessary to determine the amount of flat real estate required to construct the ponds and passive facilities. The absence of suitable flat ground on site is a major constraint on passive systems. A small passive system would improve the quality of water entering the King Creek drainage.

Low Permeability Reclamation Capping – The ultimate performance of the existing vegetation covers at reducing infiltration is still unknown due to the relatively short time they have been in place. These vegetation covers could be replaced with barrier covers composed of synthetic material. The cost to cap the leach pads, dikes, and dumps with barrier covers is considerably more than the cost to operate the current treatment systems into perpetuity ($ 33.9 million). More importantly, capping the mine waste with barrier covers will only reduce, not eliminate, the production of acid rock drainage. Therefore, operation of the water treatment plants or possibly a passive system (that would require additional capital) would still be necessary. The cost to cap only the Landusky Mine 87/91 leach pads is estimated at $30 million. The most economical and technically reliable alternative is to continue to operate the current system and to continuously improve and fine-tune the treatment processes.

Power Generation - Electricity to operate the pumps and treatment plants presently costs about $260,000 per year and will probably increase in the future. Preliminary studies show that the average wind speed at the Landusky Mine is 17 mph, which is considered very high. Wind power could theoretically be used to generate power and perhaps generate revenue to offset other costs. The site probably has sufficient wind and real estate to generate 50 to 100 MW of power. Presently, the site uses less than 3 million kw-hr each year. This averages about 400 kw constant demand with a peak of about 1200 kw (or 1.2 MW) when the big pumps are turned on. Wind turbines could be used to provide intermittent power for the project. Since the wind does not blow continuously, it is not possible to generate 100% of the power needed by wind alone without relying on power from the local power grid owned by Big Flat Electric.

The economics of wind power are very sensitive to the size of the wind turbine. A turbine sized to satisfy the exact needs of each mine would cost about $0.02/kw-hr to operate and about $0.05-$0.06 for the capital costs. If the capital costs were paid for by a grant or through a demonstration project, then wind power has the potential to reduce about 40% of the yearly costs by about 5/7 or $74,000 per year (5/7 x 40% of $260,000) at current power rates. In other words, annual power costs could be cut by 28% if wind power generators were installed to supplement the power supplied from the local power grid.