These two C36-7M units are rumoured to be getting scrapped shortly. They have been sitting here on a spur within the Seven Mile complex for many years, since ~2009.
History - 5051 [Bill] started life for Mount Newman Mining as an ALCo C636 model originally numbered 5461 and built by AE Goodwin (NSW) in 1969 with serial number G-6035-2. In 1987, in a world first, eight ALCo C636 locomotives were rebuilt into GE C36-7 units, with everything above the frame new, and the bogies and fuel tanks remaining ALCo. 5461 was rebuilt by Goninan at their Welshpool WA plant into 5507 with new serial number4839-03/87-072. 5507 went on to carry several names, in 1991 the original name was transposed with 5506 following repainting from Mt Newman orange to BHP blue, then other changes took place. When delivered 5507 carried Ethel Creek. Then 5507, once wearing BHP livery carried Mt Whaleback, then Corunna Downs and finally Nimingarra. 5507 along with the entire C36-7M fleet were retired in 1999 after the new AC6000CW locomotives were delivered. After a period of storage at Nelson Point, then the Flashbutt yard, and then back to Nelson Point, they were sold, four units to Goninan and four units to Asset Kinetics.
5507 has the distinction of carrying four names for Mt Newman / BHP Iron Ore and two liveries, and then a further livery once overhauled and leased to Pilbara Rail as 5051 when used as a yard pilot loco in the striking Pilbara Rail livery operating out of Dampier's Seven Mile yard with sister loco 5052 [Ben] which is an overhauled 5508.
***Postscript, I have been informed, on the 8th of June 2023, that both 5051 and 5052 have now been moved to the 2 Mile yard, no doubt scrapping them is easier there.