Many thanks to David Hibberd
ICI Severnside Two 0-6-0 Yorkshire Engine Co 'Janus' shunters. These were: 'Iburndale', Works No 2725 built in 1958 and 'Kildale', Works No 2741 built in 1959. I would say Derek's picture shows 'Kildale' based on the nameplate size.
According to information posted on the RCTS Mystery Photographs site along with a 1968 photo of a single car DMU at Severn Beach, the Janus shunters used to come out onto the former Pilning line to assist with shunting trains into and out of the ICI plant that was located on the Avonmouth side of Severn Beach station.
Reference: The Bristol Railway Archive. Post subject: Industrial Railways in the Bristol area, date posted 23.04.2010
Reference: RCTS Mystery Photographs. Severn Beach. Posts dated between November 2010 and February 2011
Reference: Flickr EN L Kildale Severnside. A good B/W shot of 'Kildale' working within the Severnside plant on 25th June 1990. No other details found on the fate of this loco.
Reference: Flickr Gordon Edgar ICI Severnside Works. A nice photo dated 07.03.1970 of 'Iburndale' in the ICI Severnside complex. A comment below the photo says that this loco was located at Flixborough Wharf in 1994, was moved to Morley Waste Traders at Ripponden, West Yorkshire by 22.08.2008 and scrapped before 18.03.2011. The shunters were both plated to run on BR metals.
Another good week of contributions on the site, especially Ron's D1057 shots and John's Somerton 'Western' to name two.
Best regards for now. Very many thanks indeed to you Guy