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Just around noon the San Manuel Arizona Railroad's train comes into town to exchange cars with the SP. Engines 17 and 16 are GP38s built in 1972. The SMA began operating in 1955 and runs 30 miles south to the San Manuel copper mine and smelter. The smelter produced 325,000 tons of refined copper per year. The mine and smelter shut down in 1999. The picture above is on disk 57.
During our December 1972 trip we visited the San Manuel Arizona Railroad's operation at San Manuel. A loaded train from the mine is just entering the dumper.