Ambler Metals finishes summer drilling meant to shape Arctic copper mine design

Ambler Metals completed all 42 geotechnical, hydrogeological, condemnation and exploration holes planned for the 2026 season at the proposed Arctic copper mine in northwestern Alaska's Ambler Mining District, Trilogy Metals Inc. said in a federal securities filing on Oct. 21. The company said the roughly 5,200 meters of drilling was designed to inform mine design and infrastructure placement and to support the permitting process.

Ambler Metals is a 50-50 joint venture of Trilogy and South32 Limited. Arctic is part of its Upper Kobuk Mineral Projects, which also hold the Bornite copper-cobalt deposit. Arctic is proposed 22 miles from Kobuk, Alaska News reported in July.

The drilling concentrated on the mine's proposed waste rock storage facilities, tailings footprint areas and groundwater characterization targets, along with exploration targets on the Arctic mineral horizon.

"This summer's program gives our engineers the geotechnical and hydrogeological data they need to finalize Arctic's mine design and infrastructure placement, and it strengthens the technical record supporting our permit applications," said Tony Giardini, president and chief executive of Trilogy.

Ambler Metals also assessed drill targets along the 100-kilometer volcanogenic massive sulfide belt that hosts Arctic. The belt has about 30 known historic occurrences and electromagnetic anomalies, the company said. It said the results will be used to rank targets and plan accelerated exploration and development drilling in 2027, including at Bornite.

The company is targeting a draft environmental impact statement in October 2027 and a record of decision in September 2028. The government's permitting dashboard lists the review as in progress and estimates completion on Nov. 26, 2028. Alaska News reported Sept. 21 that the Army Corps was starting that review.

The filing names pending litigation and permitting timelines among the risks that could change the company's expectations. Ambler Metals has an agreement with NANA Regional Corporation, an Alaska Native corporation, that the filing describes as a framework for exploration and potential development of the district in cooperation with local communities.

At an Alaska Industrial Development and Export Authority board meeting in Kotzebue on Sept. 22, a testifier said public discussion of the Ambler Road had never considered the effects of the industrial mining complex it would open on caribou, water quality and fish. The testifier said mining in the district could spread for decades, as Red Dog is expanding now.

Field operations are expected to restart in April or May 2027.