Located completely on private land, our underground mine will have an extremely small foot print above and below ground. The underground workings contain approx. 11.6 million tonnes of copper encompassed in an area of 3,000 feet by 2,000 feet. The surface disturbance of the mine workings will be around 270 acres surrounded by a tall wildlife protection fence which includes the 80 acre cemented tailings facility, 20 acre process water pond, all roads, parking areas, plant facilities, and the temporary waste rock storage areas.

Mining of the Johnny Lee deposit requires only a small underground operation by modern standards. The upper zone is 3,000 feet long in a north south direction, and 1500 feet wide in an east west direction. The Johnny Lee lower zone lies 1500 feet below the bottom of the Sheep Creek Valley, and gently rises to a depth of 1100 feet on its western end. The lower zone is 3,000 feet long in an east west direction. The surface opening (portal) for the 5,000 foot long access tunnel for the Johnny Lee deposit will lay on the south side of Sawmill Hill, well outside the Sheep Creek Valley and is 200 feet above the water table. This deposit hosts just under one billion pounds of high grade copper.

The mining method contemplated in the PEA is called both “cut and fill” or “drift and fill”, which means that part of the deposit will be mined out (cut) and paste backfill non-mineralized rock will be placed in that opening (fill). This greatly reduces the amount of tailings that are stored at surface level as approximately half of the tailings will be placed back underground as paste backfill. Sandfire is evaluating various scenarios to minimize the amount of tailings to be stored at surface.Read More

Once the mined rock is taken from a mine, it is ground to a fine powder in a mill located onsite. There, the copper mineral (chalcopyrite) is separated from the remainder of the rock into a concentrate for shipping. The remaining rock is called tailings.

Black Butte will have a very small footprint with a total area of mine operations close to 270 acres, with in this fenced in area, the cemented tailings facility is 80 acres, the process water pond is 17 acres, and the plant site itself is 14 acres. All areas will be reclaimed at the end of mining. The company secures a bond before construction starts ensuring that sufficient funds are available to properly reclaim all site disturbances.

The underground mine tunnel entrance will be well outside of the Sheep Creek Valley and will form the main haulage way for equipment and workers between the surface and the underground mine development. It will be developed using the drill and blast method. Drill jumbos (underground mechanized drilling machines) will drill 1.75in diameter holes which will be loaded with explosives and then blasted. The broken rock (called muck) will be removed, the roof will be stabilized by bolting, and then the process will begin again. Each cycle advances the decline approximately 14 feet. As currently planned, the decline will be approximately 17ft X 17ft.

Yes, Black Butte involves only underground mining accessed by a tunnel well outside the Sheep Creek Valley.

There will never be any mining from an “open pit”, dramatically reducing our environmental footprint and insuring continued historical uses of the land including cattle grazing and outdoor recreation.

The Black Butte Copper Project will always be an underground mine for the following reasons:

1. We have long term contractual agreements with the rancher land owners that there will never be any open pit mining on their property.
2. These types of deposits are best accessed underground as they are very deep.
3. It is the philosophy of our company that only underground mining fits this environment to properly protect it.

In Montana, construction can begin after a Mine Operating Permit (MOP) is issued by the Montana Department of Environmental Quality (DEQ) and the company has a reclamation bond in place. This will take some time because part of the permitting process is an Environmental Impact Statement (EIS) process requiring substantial review including a public comment period. If the MOP for Black Butte is approved by the DEQ, construction of the mine is expected to take approximately 24 months.