Thanks for that. I checked Google Maps and it didn't look too promising. Bit local knowledge confirming my doubts
The public footpath to the north of the A50 would be your best viewpoint. There is a steel sided bridge over the start of the fan of sidings. You will need something to stand on as it has high sides.
Directions:
From the canal towpath by the incinerator (shown as MES Environmental on Google) you go up the ramp, over the canal on the south side of the A50, loop around to go under the A50 then turn right to head along the north side of the A50. The path continues on the north side of the A50 to Heron Cross. Parking is difficult, lots of double yellows to deal with employees at nearby warehouses and football fans when a match is on. Somewhere along Grove Road / Whieldon Road, or one of the streets off, is probably your closest option, you can cross the open space from the end of Kemball Avenue.
I'm not sure what you can see from the open space directly east of the works, across the mainline, but there is nothing to prevent access - except prickly bushes and possibly degenerates.