| In 1983, the Hecla Mining Company organized a Mining Research Department to identify and test alternate technologies and techniques which would improve the safety and profitability of its operations. A direct benefit realized from the formation of the Mining Research Department was the conceptual identification, design and testing of the Lucky Friday Underhand Longwall (LFUL) Mining Method, which not only reduced the cost of operations by 25%, but also reduced the incidence and magnitude of rock bursts at the Lucky Friday Mine.; The method, as designed, consisted of a longwall undercut consolidated backfill in conjunction with diesel powered LHD's for ore transport. A footwall ramp system was developed to allow broken material to be transported to haulage levels below the mining horizon. Ten ton ore cars were introduced to increase the mine's haulage capacities. |
