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This former Southern Pacific RS11 2921 (renumbered from 5856) had been used for reclamation work at the Anaconda Bluewater Mill (uranium plant) and was now bound for the Apache Railway to become their engine 901. After repairs, the unit was moved to Holbrook and the Apache took the engine to its shop where it became a source of parts for their Alco locomotives. I think it was built in 1959 and left the SP system in 1982.
Later on the afternoon of July 23, 1988 train 823 stopped and cut the power off of its train in order to provide air for testing the brake system on the unit. Train 823 had engines 5087, 5252, 5366, and 8037. You will see this train later in this series at Baca. Storm clouds were blowing in, so I decided to put the camera away as I was losing my light and there were no more trains to chase. Disk 64