Sketches of Alaska: Modern Placer Drift Mining Chatanika ...
Nov 05, 2011· I had a mining engineer friend who, knowing I was interested in modern mining as well as mining history, invited me to see an operating placer drift mine operation in the Chatanika Valley. In placer drift mines, vertical or diagonal shafts are sunk into alluvial deposits (usually to bedrock where the gold accumulates) and horizontal tunnels (the drifts) are dug following the gold deposit.