Yes,there was a derailment after this initial delivery of two cars. BP can only unload one car at a time,
so when BO-1 went to pull out the empty and re-spot the load, the unit went on the ground (slightly behind
where the photographer is standing). Meanwhile,a third load arrived and stored at the end of the old MS
Walker spur at 3rd Avenue.
The track was fixed, so the original empty was pulled (was left at MS Walker) and the other load spotted.