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Just outside of Butte is Rocker, MT. The Butte, Anaconda, & Pacific had a small yard there. The BAP was started by the Anaconda Copper Mining Company in 1892. The line electrified its operation in 1913. This lasted until 1967 when operations went to all diesel engines.
BAP 101 had been switching a few cars in the small yard at Rocker on June 20, 1979. Disk 12
Two years later on June 19 engine 102 was pushing mill gondolas over the scales at Rocker. Although the scale is about 50 feet long, mill gondolas are longer, so the crew has to weigh each car one truck at a time. Disk 12