I received an email from someone whose memory must be better than mine, and a little more interesting info on the bin I didn't know.
First, the sand bin was apparently filled from the ramp track behind the coal tower. After the tower was removed in the Spring of '68, filling the bin was problematic so it was removed to allow a truck to drive in and dump sand outside the shed door. The bin was apparently gone in '71.
Thanks to Mr. Elf for the clarification and correction, and as I suggested, I'm sure Thomas is available if you need help down there.