The Ridgeway gold mining operations, with a work force of 165, is owned and operated by the Kennecott Ridgeway Mining Company, and is located 18 miles northeast of Columbia, South Carolina. Gold production began in 1988. Ridgeway is an open pit mine that uses the standard procedures of drilling, loading, and hauling. Ore is processed through a crushing and grinding stage before being fed through a line of 10 agitation tanks, where gold is dissolved in solution.
Gold is adsorbed from the solution onto activated carbon granules.
Gold-bearing carbon granules are treated in an enclosed tank, followed by a stripping column where gold is dissolved in a hot caustic solution under pressure. From the stripping column, gold is electroplated onto steel wool cathodes, which are transferred to electro-refining cells where the gold is plated onto stainless steel sheets. Gold is removed from the stainless steel sheets, melted in a crucible furnace, and cast as 700-ounce dore' bars containing about 60 percent gold and 40 percent silver. Mining at Ridgeway is expected to continue until late 1999, when ore reserves will be exhausted. In the South Pit, mining has ceased and backfill reclamation is in progress.