The Vancouver-headquartered company said the amended QML allowed underground operations to start at the Bermingham, Flame & Moth, Bellekeno, and Lucky Queen silver deposits, and the Onek zinc-silver deposit, for 17 years. Waste rock and dry stack tailings facilities could also be built and operated.

The QML allowed the Keno District Mill to operate at 400 tonnes a day.

Alexco CEO Clynt Nauman said the permit enabled the company to "immediately advance" the remaining underground development necessary to reach the production areas at Flame & Moth and Bermingham.

Alexco said the WUL was currently in the final stages of the permitting process to include Bermingham, and renew authorisations at other project areas to use and return treated water from mine water treatment plants, and to deposit tailings and waste rock into their respective facilities.

A technical pre-hearing conference for the WUL scheduled for early December, after which issuing of the WUL renewal would be subject to consideration by the Yukon Water Board, would likely extend into the first quarter of 2020, the company said.

Alexco has twice previously postponed an underground production decision citing unreliable permitting timelines. Once it has made a development decision, it could take 6-8 months to move into production.

Alexco is clearly getting ready for action at Keno Hill with the appointment of Wayne Zigarlick as VP operations and GM for Keno Hill. A mining veteran with more than 30 years' experience in North America, Zigarlick previously held senior management roles at Echo Bay Mines, Kinross Gold and Coeur Mining.

Over the past eight years, Zigarlick was GM at the Kensington underground mine north of Juneau, Alaska, as well as GM at the Silvertip mine in northern British Columbia.

Alexco shares (TSX:AXU) gained 4.35%, or C10c, Monday to close at $2.40, which capitalises the explorer at $285 million.