Southeast Alaska mines nearing release of key economic assessments


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Mining projects are on a roll in southern Southeast Alaska.

Heatherdale Resources Ltd. plans to have a pre-feasibility study, an important stage in mine development, done for its proposed Niblack multi-metals mine in mid-2013.

The company hopes to be able to apply for permits to build the mine in mid-2015, according to Heatherdale CEO Patrick Smith.

Niblack is on Prince of Wales Island about 27 miles from Ketchikan, and is blessed with good tidewater access, Smith told the Alaska Miners Association at the group’s annual convention in Anchorage Nov. 8.

If developed, Niblack could produce 1,500 to 2,000 tons of ore per day under the current plan. The ore contains copper, gold, zinc and silver, with much of the value in the copper and gold, Smith said. It would be an underground mine similar to the existing Greens Creek Mine on Admiralty Island near Juneau, Smith said.

An important development is that Heatherdale hopes to finalize a plan to process ore from Niblack in a processing plant in Ketchikan, Smith said.

Ore would be shipped by barge to a proposed plant at an industrial site on Gravina Island, the location of a former sawmill that has access to inexpensive hydro power provided by way of submarine cable from the nearby Ketchikan community.

Building the mill at Gravina Island, if the plan proceeds, would require about 200 construction workers and would take about 18 months, Smith said.

Another Southeast proposed underground mining project at an advanced stage is a rare earths project at Bokan Mountain, also on Prince of Wales Island bout 35 miles from Ketchikan, and also with good access by water.

Ucore Rare Metals Inc., the developer, plans to have its preliminary economic assessment completed and published very soon, Ucore’s chief operating officer, Ken Collison, told the AMA, also on Nov. 8.

A press release with the major conclusions of the PEA would be published first, and followed 45 days later with the release of the full report.

The schedule now calls for a feasibility study for the mine, the final step before approval by the owners, to be completed by the end of 2013.

“Once permits are issued, and how long that will take is the big question, construction would take about one-and-a-half years,” Collison told the miners association.

Ucore would mine just more than 1,000 tons of ore per day but would use a new crushing sorting technique to identify ore with the highest content of rare earths, Collison said. Only about 375 tons of ore per day would be processed.

The remaining waste rock would be temporarily stored on the surface but would eventually be placed back underground as “back-fill” in the mine.

If the mine proceeds to production it would employ about 170 in its operations, with hourly workers on a two-week on, two-week off schedule and members of the management team on a one-week on, one-week off schedule. Ucore also plans to open an office in Ketchikan soon.

The power requirement at a Bokan Mountain mine would be about 3 to 4 megawatts in operation but at the beginning, when the ore process mill is being started, the requirement is expected to reach 6 megawatts.

Collison said Ucore is discussing the possibility of importing liquefied natural gas, or LNG, from a supplier in the Pacific Northwest to fuel power generation.

“It would be about half the cost of using diesel,” he said.

The plan now is to make two concentrates at the mine containing rare earth elements, but Ucore is also experimenting with a new technology that could allow the concentrates to be separated into three rare earth metals at the mine.

The elements would be dysprosium, neodymium and erbium. Laboratory tests performed by IntelliMet LLC, a Montana firm, have demonstrated that the elements can be successfully separated from a composite of solutions that replicate the ores to be mined at Bokan Mountain, Ucore announced Oct. 3 in a press release.

If processing of the rare earth metals could be done at the site it would lessen the dependence of the U.S. on China as a source of rare earth processing. Rare earths are commonly used in technology systems.

Westmountain Gold produces first gold bar at Terra Project

WestMountain Gold has completed analysis of gold and silver concentrates produced in a test run of a pilot processing mill at the company’s Terra project, a mine near the Alaska Range. The company also produced its first gold bar as part of the tests.

“The assay results of gold concentrates from the Terra project mill are 71 percent gold and 29 percent silver. The gold recovery from the first metallurgical testing of the concentrates is greater than 98.5 percent recovered from the concentrate,” the company said in a Nov. 16 press release.

Small quantities of copper, tungsten, antimony and zinc are also present in the ore, the tests have indicated.

A 401-gram gold bar was produced from which 9 ounces of gold and 4 ounces of silver can be recovered through additional refining, the tests indicated.

WestMountain president Greg Schifrin said, “The Terra Project mill has produced high concentration gold from the gravity mill. We are enthusiastic about the equipment and pilot mill upgrades underway and the anticipated production during the upcoming 2013 season.”

Northern Dynasty to own share in “Big Chunk,” near Pebble

Northern Dynasty Minerals has securing a major ownership share in the “Big Chunk” group of state mining claims located near the large Pebble copper/gold prospect near Iliamna southwest of Anchorage.

The agreement between Northern Dynasty, which owns 50 percent of Pebble, and Liberty Star Uranium & Metals Corp., provides for Northern Dynasty to obtain ownership of 199 state mining claims in the “south block” part of the Big Chunk project to satisfy a $4 million loan made to Liberty Star.

Tucson, Ariz.-based Liberty Star will retain 229 mining claims in the prospect area. Liberty Star also owns 184 mining claims in the “north block” part of the prospect area.

Liberty Star did limited test drilling on the Big Chunk project in 2012 and has identified seven other targets through geochemical analysis, according to the company’s chief geologist, Jim Briscoe.

 

Tim Bradner can be reached at

tim.bradner@alaskajournal.com.

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