Donlin Gold has taken another step toward opening its proposed mine. State regulators have sent Donlin a draft permit for discharging wastewater into Crooked Creek before it flows into the Kuskokwim River.
For Donlin Gold to operate its proposed mine it’s going to need lots of water: about 17,500 gallons per minute throughout the life of the mine. Most of the water will come from the ground and be used to separate microscopic flecks of gold embedded in the rock. The process will release heavy metals and rely on cyanide.
Diverting the water will reduce the amount in surrounding streams; in some designs, miles of fish-supporting waterways would be lost.
Then there’s the water that is produced by the mine: seeping from the tailings, or the left over rock at the mine, water from the workers’ camp, and water that drains into the mine pit.
All that water needs a place to go. After it’s been treated, Donlin wants to empty it into Crooked Creek, about 10 miles north of the village of Crooked Creek and the Kuskokwim River. The company has received a draft permit from the Alaska Department of Environmental Conservation to do just that. The permit sets the standards for that water.
“The water quality still has to meet the water quality standards under the Clean Water Act,” Allan Nakanishi, the state’s technical engineer on the project, said.
And under state law, the discharged water has to “be adequate to fully protect existing uses of the water.” One of those uses is fishing. The Kuskokwim’s five salmon species have been recorded in Crooked Creek as well as 12 resident fish species. Donlin plans to treat the water with reverse osmosis, a process for removing substances dissolved in water.
“The treatment plant itself is going to operate from early April through the end of October,” Donlin spokesperson Kurt Parkan said. “So during the summer season.”
Donlin will recycle the water during the rest of the year. Contaminants removed from the water will be dumped into the tailings. If approved, the permit would require the discharged water to be tested once a month, with possible legal action to be taken if the standards are not met.
Donlin has had 10 days to comment on the draft permit before the period closes Wednesday. The state will open a 60-day public comment period in mid-December and hold three public hearings in late January. Hearings will be in Bethel, Aniak and Anchorage, and will cover not only this wastewater discharge draft permit, but also draft permits for waste management and the project’s reclamation and closure.