It is business as usual at Red Dog, the world's largest producer of zinc concentrates.

But a new general manager is in charge of guiding operations at the huge production facility 90 miles north of Kotzebue.

John Knapp, 49, took on the top job at Red Dog earlier in December, when his boss, Robert G. Scott, was appointed vice president of base metal mining at Teck Cominco Ltd., the mine's owner....