Commodities: Copper (Cu), Molybdenum (Mo), Gold (Au), Silver (Ag)
Location: Huckleberry Mine is located about 123km (by road) southwest of Houston, BC.
Geology and Type of Deposit: Huckleberry is located in the Intermontane Belt of the Canadian Cordillera. This ore is a copper-molybdenum porphyry deposit that is hosted in Jurassic volcanic rocks (tuff) intruded by younger (Cretaceous) granodiorite. The main ore minerals are chalcopyrite and molybdenite that occur mainly in fractures and veins. Gold (Au) and silver (Ag) are also present.
The Operation: The Huckleberry deposit was first discovered in 1962. Construction of the open pit began in 1996 and operations started in October 1997 at a cost of C$142 million. The mine property occupies 19,780 hectares of land. Mining here ceased in August 2016 due to low copper and molybdenite prices, and the mine was placed in Care & Maintenance status.
Huckleberry Mine is owned and operated by Huckleberry Mines Ltd which is owned by Imperial Metals. In 2015, the last full year of production, the mill processed 20,000 tonnes of ore per day, producing more than 43 million lbs of copper, 3,500 ounces of gold, and 206,000 ounces of silver. If the mine goes back into production, the reserves could extend the mine life for 5 years.
Mining: When in operation, the ore is extracted using conventional open pit methods. After drilling and blasting the ore is loaded by a shovel, backhoe, or loader into haul trucks that haul the ore about 1 km to the crusher located next to the mill. Excavated waste rock is loaded into haul trucks and hauled to the tailings impoundment where some of it is used to construct the dam and the remainder is dumped in the impoundment to be stored under water forever.
Processing: From the primary crusher the ore is conveyed to a stockpile, and from there is fed to the mill. There, ore moves with water through a sequence of mills that reduce it to sand size particles. The sandy ore slurry is piped to a series of froth flotation cells, where copper minerals and molybdenum minerals are separately floated and collected. The mineral concentrates are piped to thickener cells and then to a filter press to eliminate most of the water. The two concentrates are stored under cover before shipping.
Tailings are piped from the mill to a new tailings management facility. The water in the pond is returned to the mill and used again.
Markets: Copper concentrate produced at Huckleberry is trucked to Stewart, BC for storage, and then shipped across the Pacific Ocean to smelters and refineries in Japan. Molybdenum concentrate is trucked to Vancouver where it is sold to a broker and shipped to Europe through the Port of Vancouver.
Community and Employment: Prior to the 2016 shut down Huckleberry employed 260 people. Most of them (80%) live in the Bulkley Valley communities of Houston, Smithers, Telkwa, Topley, Granisle and Burns Lake. They travel to and from the mine on a company bus, which travels along a 123 km forest service road from Houston. Employees live in dormitories on site during their work shifts. Each employee is given a private room and free meals, with access to TV, radio, internet, fitness room, library, and other forms of entertainment.
Environmental Considerations: The area surrounding Huckleberry mine is sub-alpine forest. Wildlife in this area includes black bear and moose, which are commonly seen, as well as grizzly bears, caribou, wolves, mountain goats, and many smaller mammals like fox, pine martin and porcupines. Huckleberry's reclamation plan is to restore the site to forests and wildlife habitat. All buildings will be removed, and the site will be covered with native vegetation.
When it is operation, water from the tailings management facility is recycled back to the mill, while excess runoff is pumped to a nearby receiving stream. All run-off and surface water at the mine passes through settling ponds to ensure its cleanliness before it is allowed to re-enter the environment.
The formation of acid rock drainage is a main concern at Huckleberry. Waste rock is routinely tested to determine if it is potentially acid-generating or not. Non-acid-generating rock (NAG) can be used to construct the tailings dam or other projects. Potentially-acid-generating rock (PAG) is stored under water in a tailings management facility where it will not be exposed to air, which is necessary to form acidic drainage.
Annual reclamation activities are on-going. In 2015 the BC Technical and Research Committee on Reclamation awarded Huckleberry Mines the Metal Mine Reclamation Award for its habitat compensation work, involving the successful remediation of fish-ways in a local creek that was completed in collaboration with local First Nations.