The locomotive in question is Peckett No. 2013, an industrial locomotive that never worked in the Forest and one of several owned  by Fred Watkins.

The location is the end of the truncated GWR Coleford/Monmouth line at Whitecliff Quarry, which Fred Watkins owned from the mid 1940s to the mid 1960s, where he stored the loco in question. How it ended up wedged in the buffer stop is still a mystery.

– Martin Vincent, by e-mail.