Constantine Metal Resources last week won agency approval for 2.5 miles of additional roads, 120 feet of bridges and other infrastructure at the Palmer deposit, a potential mine site near the Canada border.

The “no significant impact” decision favoring the Canada-based exploration company came with completion of an environmental assessment by the federal Bureau of Land Management.

The road straddles the southeast side of Glacier Creek, which flows into the Klehini River about five miles south of the ore deposit.

Dolly Varden trout spawn in Glacier Creek. Coho salmon rear and spawn in a tributary to Glacier Creek located at the lower end of the creek.

Constantine president and CEO Garfield McVeigh this week said the additional road work and improvements were sought to reduce helicopter overflights, improve safety and get the company closer to the source of ore that’s being explored.

“We need to continue to advance exploration and this gets us into the core area of the property. This gets us into the center of activity. It’s as close to getting into it as we can get by road,” McVeigh said.

“The safety element is also a big factor,” he said. “This will reduce helicopter requirements of our operation” as well as provide a way out for workers who might be stranded on the mountain when helicopters can’t fly due to weather.

Glacier Creek serves as a barrier for workers seeking to climb down the mountain, he said. “When you get down there, (the creek) gets pretty difficult to cross standing on your feet.”

Among environmental concerns about the project were erosion and runoff from road-building activities, including acidic runoff from exposed rock. The BLM, in its decision, requires the company to take steps to protect waterways.

“There’s a geo-mat you put down on soil cuts on steeper parts of the slope. There are ways we’re looking at to stabilize the soil,” McVeigh said. He said he saw “no chance whatsoever” that the work would create dangerous runoff. “We’re staying on the alert to cover it, but we see no risk there.”

Lynn Canal Conservation had no official response to the decision this week. President Eric Holle could not be reached. “We’re just reviewing it and evaluating it. We don’t have any specific comments on it right now. It’s quite a big document. It takes quite a bit of work to go through it,” said LCC board member Carrie Weishahn.

“Any time there’s exploration of a high-sulphide deposit, there’s a concern,” Weishahn said.

Guy Archibald of the Southeast Alaska Conservation Council said that because Constantine already has shown shareholders maps of an underground mining tunnel at the end of the road, the document should have included consideration of its construction.

“We primarily sought for BLM to exercise their requirement to consider all reasonably foreseeable future actions,” Archibald said. “Basically, they’re telling BLM one thing and they’re telling their investors something different. It’s a classic bait and switch.”

Tunneling produces waste rock and “contact water” and consideration of those elements would have triggered a federal environmental impact statement, a much higher level of review, Archibald said.

Archibald acknowledged that Constantine didn’t have permits to begin tunneling at this stage. “But it’s the destination of the road.”

Archibald also said that “geotechnical” drilling planned by the company is aimed at finding a stable place to locate a tunnel.

Archibald said the environmental assessment amounted to “incremental permitting,” which is generally not allowed.

BLM received more than 230 letters on the document, “including 14 (that) contained substantive information which was later clarified in the final EA,” according to a BLM press release.

The assessment requires Constantine to have a geologist on site during road work to watch for potential impacts. The analysis considered potential impacts to water quality, wildlife, fish and other resources.