The widespread withdrawal of 21t hoppers from the mainline network led to many being repurposed by BR or sold on to private companies for internal use. One such operator was the National Coal board who had a coal disposal site and washery at Gwaun-Cae-Gurwen, South Wales. The railhead was operated by Powell Duffryn Coal Preparation, and they required a fleet of internal user wagons for the transfer of coal around the site.During the early 1990s this fleet, made up from redundant HTV’s and HEA’s received the striking green and grey livery seen on our models. These wagons would see use right through the decade until the site was mothballed in 1999.