With the rarely photographed (on WHL) ICI chemical tanks behind the barrier wagon destined for the Wiggins Teape Pup Mill at Corpach.
5415 was not as far as I can see ETH fitted at any time, and certainly not when this photo was taken.
You may be mistakenly thinking the MU cable on the far side of the loco is an ETS/ETH cable - it is not. Indeed the MU socket is also visible on adjacent to the nearest buffer in the photo.
