The clock is running on the public comment period for the Kensington Mine's draft supplemental environmental impact statement, with public meetings scheduled in late February in Juneau and Haines.
The draft SEIS was released Friday, and includes mine developer Coeur Alaska's proposed changes to the mine plan that was approved in the late 1990s, as well as two viable alternatives.
"There is not a preferred alternative at this time," said Steve Hohensee, the U.S. Forest Service's SEIS team leader for the Kensington proposal.
"We're leaving it open until we hear comments from the public. (A preferred alternative) will be selected in the final SEIS."
The gold mine, 45 miles north of downtown Juneau, has an estimated reserve of 1.1 million ounces of gold, said Coeur Alaska Vice President Rick Richins. The mine is subject to a supplemental EIS rather than a full EIS because the project already has been permitted twice, once in 1992 and again in 1997. Since then, the company changed its plans in an effort to lower capital and operating costs.
The original plan, which is also Alternative A, or the "no action" alternative in the SEIS, would have all mining operations taking place at the Kensington mine site, which drains into Lynn Canal. The mine would use a dry tailings facility. Employees would be transported to the site by helicopter every couple of weeks and lodge at a personnel camp. The plan would allow for the mining of 4,000 tons of ore per day.
The proposed action, known in the SEIS as Alternative B, would call for the construction of some facilities in the Jualin Mine area, which drains into Berners Bay. Supplies would be shipped in and out on a barge that would dock at a facility to be built in Slate Creek Cove in Berners Bay. The plan would allow for the mining of 2,000 tons of ore per day, and ore would be accessed via a 12,000-foot tunnel connecting the two mines.
Tailings would be deposited in Lower Slate Lake - a wet tailings facility. The personnel camp would be eliminated, and a daily ferry service operating between Slate Creek Cove and Cascade Point would transport employees to and from work.
Kat Hall of the Southeast Alaska Conservation Council said the organization is concerned about the effects of the barge and ferries on the herring and eulachon populations in the water.
"Both (species) are sensitive to increases in hydrocarbons in the water, and this is generally found with increased boat traffic," Hall said.
Alternative C in the SEIS calls for the ferry service to operate between Slate Creek Cove and Echo Cove, at the end of the road in Juneau. Hohensee said the proposal arose from concerns that a ferry terminal at Cascade Point would affect herring spawning that occurs there.
There is a fourth alternative, Alternative A1, which is the same as the no action alternative except it would allow the mining of 2,000 tons of ore per day instead of 4,000 tons of ore. Hohensee said Alternative A1 was included only for comparison, and won't be chosen.
The alternatives attempt to answer issues identified during scoping meetings held in September 2002. People expressed concern that mine-related transportation would affect users of and resources in Berners Bay; that the tailings facility and other facilities would adversely affect streams and lakes as well as the marine environment; and that the tailings facility, dock, and other proposed infrastructure would blemish the landscape.
Hohensee said that except for the proposed dock at Slate Creek Cove, most of the mine facilities won't be visible from Berners Bay.
"There might from some points be a part of the mine that's visible from Berners Bay, but it has yet to be seen. It would be just a very small portion, a road cut or something," he said.
Richins said the proposed action is still Coeur Alaska's preferred plan.
"We think it has a number of environmental advantages over both other alternatives," he said.
Richins said the proposed action would disturb about 195 acres of land, whereas the no-action alternative would disturb about 287 acres.
He also said the wet tailings facility in Lower Slate Lake that is part of the proposed action would actually enhance the lake's productivity. Richins said a consultant's study shows that as the tailings are deposited in the water, the displacement would cause the lake to become shallower and to expand from 20 acres to 56 acres.
"One of the things that limits the productivity of the lake right now is that light only penetrates to a certain depth. By optimizing the depth of the lake you would be enhancing the productivity because of light penetration," Richins said.
Kensington mine alternatives
Alternative A (No Action): All operations would take place at mine site, which drains into Lynn Canal.
Dry tailings facility with wastewater discharged to Sherman Creek and tailings drained to Camp Creek.
Employees to be brought in by helicopter and to stay at personnel camp.
Would allow mining of 4,000 tons of ore per day.
Alternative B (Proposed Action): Mill and administrative facilities would be built in Johnson Creek drainage, which drains into Berners Bay.
Supplies shipped in and out by barge that would dock at a facility built in Slate Creek Cove in Berners Bay.
Ore would be accessed via a 12,000-foot tunnel connecting Jualin Mine to Kensington Mine.
Wet tailings facility would be built in Lower Slate Lake.
Personnel camp would be eliminated in favor of daily ferry service between Slate Creek Cove and Cascade Point.
Would allow for the mining of 2,000 tons of ore per day.
Alternative C: Same as Alternative B, except ferry would operate between Slate Creek Cove and Echo Cove, and Slate Creek Cove marine terminal would be a little smaller than in Alternative B.
Masha Herbst can be reached at email@example.com.
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