Cyanide:

• Cyanide is a highly concentrated poison – an amount equal to a grain of rice is lethal to humans. Fish are even more vulnerable, especially trout. The lethal concentration for trout is only 100 parts per billion – that's equal to about one cup of cyanide dissolved in the water of an olympic-size swimming pool.
• Seven-Up Pete Joint Venture (SPJV) plans to spray 9.2 million pounds of sodium cyanide each year on 880 acres of leach pads. The cyanide spray will have a concentration ranging from 53 to 265 parts per million (530 to 2,650 times the amount that will kill trout). Runoff from the leach pads will be collected in holding ponds that cover 70 acres and will contain 100 million gallons of cyanide solution. Based on experience at every other heap-leach mine in Montana, toxic cyanide solution is likely to enter the Landers Fork or Blackfoot River from surface spills, pond flooding, or from leaks in the leach pad or liner that allow the cyanide to percolate down through the coarse gravels beneath the leach pads into the groundwater.
• EPA studies have found that liners like the ones which the Seven-Up Pete Joint Venture plans to use underneath the heap-leach pads and holding ponds, average one leak per acre. That translates into 880 leaks from the heap-leach pads and 70 leaks from the holding ponds.
• Every cyanide heap-leach mine in Montana has had cyanide leaks or spills in violation of their permits. From 1982-1993, the Zortman/Landusky mines had 6 significant cyanide spills, including one that contaminated the water system of the town of Zortman. These mines are only 1/3 the size of the McDonald Meadows Project.
• Cyanide toxicity is of particular concern to those who have drinking water wells downgradient from the mine.
• Cyanide can persist almost indefinately in groundwater because the sunlight and oxygen that break cyanide down to less harmfull substances are absent. Citizens in Pony, Montana were forced to buy bottled water after the Pony mill contaminated their wells with cyanide.
  

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Acid Mine Drainage:

• Gold deposits are often found in rock that contain sulfides. When sulfides are exposed to water and oxygen, sulfuric acid is formed. This acidic water, called acid mine drainage, can also dissolve metals in the surrounding rock, and release them into streams, sediment and groundwater. The Berkeley Pit, for example, contains 11 billion gallons of toxic water with a pH of 3 (similar to battery acid).
• The upper Blackfoot River is already seriously impaired from past mining operations. The most severe impact occurred in 1975 when the Mike Horse mine tailings dam was breached by a flood and the reservoirs toxic contents were spilled into the headwaters of the Blackfoot. Many cutthroat, brown and brook trout died as a result and the river sediments remain contaminated by these metals. The area is now a state superfund site.
• When the Seven-Up Pete Joint Venture mines the McDonald Meadows pit, 980 million tons of rock will be exposed to oxygen and water for the first time. The pit walls, waste rock piles and leach pads are all potential sources of acid mine drainage. The waste rock piles will be unlined, and will leak directly into the groundwater system of the Blackfoot and Landers Fork. The pit will remain unreclaimed forever.
• According to mine operators, the amount of sulfide rock at the McDonald Meadows mine will be minimal. However, the same prediction was made at the Zortman/Landusky mine. The sulfide content was severely underestimated with devestating results. Wastewater from the mine contained arsenic, cadmium, chromium, iron, nickel and zinc at levels far exceeding state water quality standards. In 1996, the mine operators were forced to pay $37 million to settle a lawsuit for violations of the Clean Water Act due to acid mine drainage and other problems.
• In 1995, the legislature weakened Montana's water quality standards for arsenic from the level expected to produce 1 cancer death per 1,000,000 people to 1 cancer death per 1,000 people.
  

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Groundwater Pumping:

• The McDonald Meadows minewill be dug far into the ground – 800 feet below the surface of the Blackfoot River and Landers Fork. To dewater the pit and keep mine operations dry, an elaborate pumping system will pump an average of 2.5 million gallons of groundwater a day and discharge it into gravel ditches along the banks of the Landers Fork and Blackfoot River.
• Manipulation of this gigantic volume of water will likely result in substantial changes to the Blackfoot River system including: increases in water temperature, changes in flows and even localized dewatering. This would be particularly harmful to the endangered bulltrout, which have very specific flow and temperature requirements for spawning and migration.
• The mine is located less than 10 miles from Rogers Pass, the site of the coldest air temperature ever recorded in Montana (-70 F). Even under the best circumstances, equipment will likely experience failures. A failure in the pump system, for even a short period, will draw water back towards the pit. The Blackfoot and Landers Fork could suffer severe dewatering as a result.
• Zinc, iron and manganese will be discharged into groundwater systems at levels higher than state water quality standards. Canyon Resources plans to use an 8-mile mixing zone (4 miles of the Landers Fork and 4 miles of the Blackfoot River) to dilute the discharge water containing these heavy metals. Heavy metals, however, are not biodegradable. They simply settle to the streambed where they will contaminate the aquatic insects which live and feed there. The insects, in turn, will contaminate the fish that depend on them for food.

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Nitrates:

• Nitrates are one of the major fertilizers or nutrients that encourage algae growth. Elevated nitrate levels in rivers and lakes often cause large mats of algae to grow, depleting the oxygen supply, choking out fish and clogging irrigation ditches.
• Nitrate residue, originating from the 27 million pounds of ammonium nitrate that will be used to blast the pit, will enter the rivers in stormwater run-off and in seepage from the leach pads or waste rock piles.
• Seepage water from the waste rock piles is estimated to contain nitrate concentrations of 7.2 ppm. Heavy algae growth occurs in the Clark Fork River at soluble nitrogen concentrations as low as .25 ppm.
• The Department of Environmental Quality anticipates that nitrate pollution problems will be so long lasting that water treatment facilities at the mine will have to be operated forever.

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Sediment:

• Sediment sources at the mine would be substantial since over 4 square miles of land surface will be disturbed, and the mine's plan of operation calls for the relocation of 3 miles of Highway 200 closer to the river.
• SPJV has estimated that over 2 million cubic yards of soil will be lost during the project life.
• Although the mine plans to remove much of the sediment with a storm water treatment system, some of this material will reach the Blackfoot and Landers Fork in quantities greater than would naturally occur.
• In June 1964 and 1977, major storms and flooding caused significant damage throughout the Blackfoot Valley. If storms of this magnitude were to occur during the mine's operation, even the best designed storm- water treatment system could partially or totally fail.
• Bulltrout and westslope cutthroat are highly sensitve to increases in fine sediment, particularly during spawning, embryo development and rearing stages.

IMPACT ON FISHERIES
FACTS ABOUT THE MINE

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