Caption: A major component of keeping the roadbed clean and able to properly drain is ballast undercutting. Back in the 80's, 90's and 2000's, CN had several Plasser RM-76 UHR ballast undercutters across the system. CN 50553, s/n 203, built in 1981 is seen here sitting in the Transcona Work Equipment Yard after a long season of undercutting, waiting its turn to go through the shop for necessary repairs before once again heading out for another work program.