Case Study: Mining and Fish Hatchery Co-existing in Alaska
The development of a mine, when well planned, can provide opportunities to address past mining impacts and even create the potential to enhance the surrounding environment. At our Fort Knox facility in Fairbanks, Alaska, mine development has created a self-sustaining Arctic grayling fishery in the waterways immediately downstream of the operation.
Fort Knox is located on Fish Creek about 42 kilometres (26 miles) northeast of Fairbanks in one of the largest gold producing areas in Alaska. Prior to the 1992 development of the current mine, Fish Creek had been classified as an impaired water body by the state’s Department of Environmental Conservation and the U.S. Environmental Protection Agency, as a result of mining activities that had been underway since the Fairbanks Gold Rush of the early 1900s. Water quality and fish habitat were seriously undermined by excessive sediment concentrations, uncontrolled run-off and erosion. Fish populations, including those of the Arctic grayling and the burbot, were decimated.
The development of the new mine created opportunities to fix the damage and revitalize the stream’s fisheries. This included restoration of 2.4 kilometres (1.5 miles) of Fish Creek and neighbouring wetlands, which eliminated major sources of sediment and contamination in the stream. It also involved consultation with local officials to ensure that the 70-hectare (175-acre) freshwater reservoir required for mine operations would also enhance habitat. By implementing these measures, we were successful in restoring a habitat where native fish populations could thrive. The initial goal was to create a self-sustaining Arctic grayling population of between 800 and 1,600 fish within 10 years of waterway restoration; in reality, monitoring by Alaska’s Department of Fish and Game (ADF&G) showed that this goal was achieved in just two years. By 2013, ADF&G monitoring shows the grayling population has grown to more than 7,400, the burbot is self-sustaining, and the habitat is supporting a variety of birds and wildlife, including the horned grebe, osprey, bald eagle, mink, otter and other species that feed on the fish.
The fact that such success has been achieved in an area immediately downstream of the mine’s tailings storage facility is indicative of the high level of environmental protection that is central to ongoing operations at Fort Knox. The facility was designed to operate as a zero-discharge system (in other words, all mine- and process-related water and run-off are retained in the facility) to provide ongoing downstream protection of the fishery and waterway. A series of drains and cut-off wells collect water that seeps under the dam and pumps it back to the facilities. Back-up systems, which are tested regularly, ensure the wells continue operating even in the event of a power outage.
In addition, there is an extensive program of daily and weekly inspections to promptly address issues that may arise. Kinross technicians sample surface and groundwater quarterly, and manage a storm water pollution protection plan below the tailings dam. Summaries of this monitoring are in our annual reports available on the Alaska Department of Natural Resources website (http://dnr.alaska.gov/mlw/mining/largemine/fortknox/pdf/fgmi2013ar.pdf). We also fund ADF&G to monitor water quality in the reservoir and to track annual Arctic grayling and burbot populations. In addition, we undertake periodic upkeep of the restored creek and wetlands, including clearing beaver dams so that the graylings have clear passage to their spawning habitat in the wetland and overwintering habitat in the reservoir.
Having successfully revitalized an important habitat for fish and wildlife, our goal today is to sustain this success well into the future – for the enjoyment and recreational use by people of Alaska long after the mine is closed and our reclamation work is complete.
“I think this is a fantastic example of how mining and fish can not only co-exist but actually the fish can benefit from the efforts of mining.”Delbert Parr, Environmental Manager, Fort Knox