Yes, water monitoring is important and accomplishes two things. First, it allows us to establish a baseline understanding of water quality and quantity under conditions prior to mining. Second, after mining is underway, monitoring allows us to detect any changes in water quality or quantity. Montana has very stringent water quality laws that protect the environment by stipulating that if we are not meeting all standards, we will be shut down immediately until resolution that protects the environment is completed.
Category Water & The Environment
We are keen to improve all aspects of our community including opportunities for recreationists and tourists. We are working with our Meagher County Stewardship Council for recommended projects and activities embracing positive ways we can support recreation in our community as we develop Black Butte Copper.
Yes, we are looking forward to working with our conservation community to enhance the fisheries. This is an important area for cutthroat trout restoration, and we believe there are opportunities for us to assist in these important efforts. The Meagher County Stewardship Council will help guide us with the correct direction for local conservation enhancements.
The estimated average Winter base flow in Sheep Creek around the project is 15 cfs and at its confluence with the Smith River is 30 cfs. This is during the low flow periods of November through March. The average base flow in the Smith River during this same Winter period is approximately 90-100 cfs.
All of the water not consumed by the milling process at the mine will go through the reverse osmosis (RO) water treatment plant and then be returned back to the groundwater system through an underground infiltration system. The consumptive use rate of the mine is 210 gpm; any additional water pumped from the mine will return directly to the groundwater system with the maximum amount possibly reaching up to 290 gpm). Consumed water is completely mitigated with leased water rights being returned to Sheep Creek to keep flows in balance.
Estimated dewatering rates pumped from the mine range from 220 gpm to 50 gpm as the mine access is developed. The dewatering rate during full operation is estimated between 420 and 470 gpm. All but the 210 gpm of water needed for use in the milling process returns back to the groundwater system via the underground infiltration system after treatment by the reverse osmosis water treatment system.
Our numeric hydrologic model shows that dewatering of the mine area will have an effect on the water table only in the area of the mine itself with noticeable drawdown only in the part of the bedrock hydrologic system containing the mine. Continuously backfilling the mine with cemented tailings reduces the extent of drawdown as mining advances. The water table will return to normal on completion of mining.
Sandfire has designed the BBCP to completely protect Sheep Creek and its fisheries, and in turn the Smith River and all the recreational uses and businesses supported by it. The operation will treat all water released from site to meet Montana’s strict non-degradation standards and return the treated water straight back into the ground water system through an underground infiltration system buried 6-8 feet in the ground.
Yes, the mining process may use explosives that contain nitrates during underground mining. The reverse osmosis water treatment process will remove most nitrogen from the water. The company will construct a treated water storage pond in which to contain treated water during the summer when algal growth in the streams is most easily promoted by nitrogen in the water. Any treated water stored in the pond can then be released outside the summer months. In this way, the mining operation can ensure it is able to meet the non-degradation discharge standards for nitrogen as regulated by the Montana Department of Environmental Quality.