I grew up in Plainville yard. My family had a trucking company that transloaded freight from rail to road.I remember PC, and CR, but I really got into it by the late 1980s.
In that time they had 3 jobs, PL1, WA1, and PLED/EDPL. The road job ran overnight. The units were split between the two locals. Next the cars were switched between Plainville and Waterbury. Lots of the time WA1 was heavy. PL1 would arrange to go to Carnation or New Departure, in Bristol. PL1 would push to the tunnel, and go up the branch to do Carnation.
WA1 did work in the city at Waterbury Republican, Tilcon, and Porta Nova. Sometimes they went to Albert Bros. scrap on the north end, a remnant of the Watertown Branch, and Stone Container in Torrington. Other days was to Derby Jct.
On the Derby Jct. days I sometimes got candy bars, since they spotted corn syrup at Peter Paul.
PL1 would return from Bristol and do Tilcon in Plainville, Stanley Works a and Perma Treat in New Britain. They would also work the Canal in both directions.
When PLED could no longer make it to ED, due to the deterioration of the Conn River, they changer to PLSP, which met a turn out of ED at Springfield.