Red Dog produced 1.2B lb zinc during 2017

Teck Resources Ltd. Feb. 14 reported that the Red Dog zinc mine in Northwest Alaska produced 541,900 metric tons (1.19 billion pounds) of zinc and 111,300 metric tons (245.4 million lb) of lead during 2017.

During the fourth quarter, Red Dog produced 141,200 metric tons (331.3 million lb) of zinc, which was 3 percent lower than the same period a year ago. Teck attributes this drop primarily to slightly lower mill throughput and grade. Fourth quarter lead production of 25,000 metric tons (55.1 million lb) is about 10 percent less than the final three months of 2016, as higher lead grades were more than offset by significantly lower recoveries.

During the first quarter of 2017, ore from Qanaiyaq pit was introduced to supplement declining grade ore from the Aqqaluk pit. However, mill performance was adversely affected by the metallurgically complex ores, particularly the highly oxidized material being mined at the surface of Red Dog.

Due to the difficulties, Teck cut back how much Qanaiyaq ore it was feeding the plant. As the company gained processing experience with this ore, and deepened the pit to access less weathered ore, the amount of Qanaiyaq ore in the mill feed blend increased to 20 percent during the fourth quarter. Teck expects to maintain this feed ratio in 2018.

In September, the company began a US$110-million mill upgrade project that is expected to increase average mill throughput by about 15 percent over the remaining mine life at Red Dog, helping to offset lower grades and harder ore.

The increased mill throughput is not expected to shorten the current life expectancy of Red Dog.

"Because the upgrade project will permit lower grade material to be processed, the current mine life, based on existing developed deposits, will remain unchanged through to 2031," Teck penned in its fourth quarter 2017 report.

At the beginning of the fourth quarter, the royalty paid to NANA Regional Corp. on the net proceeds of production at Red Dog increased to 35 percent.

In accordance with the operating agreement between Teck and NANA, this royalty increases by 5 percent every five years to a maximum of 50 percent. The next royalty increase is slated for Oct. 1, 2022.

Teck anticipates Red Dog will produce 525,000 to 545,000 metric tons (roughly 1.16 billion to 1.2 billion lb) of zinc and 95,000 to 100,000 metric tons (roughly 209 million to 220 million lb) of lead during 2018.

–SHANE LASLEY