I always fancied modelling an underground mine line but have never got around to it although I used to play work with the real thing once upon a good time when I was young and needed the money, a hole in the ground near Baldhu. I did maintenance on the locos and on one occasion forgot that the old Greenbat was, like a car, wired with one battery pole connected to the chassis. All the others were from Clayton and were fully insulated. The spanner slipped and shorted to the battery box, blinding flash, tops out of a dozen cells with acid spurting out over my face. Cut my Bahco adjustable spanner in two and melted a sizeable area of the battery box. Yes, fascinating things.
One train that really needs to be modelled is the 'facilities' train. Miners, having had their pasty would sometimes have a real need to use the 'facilities' - you didn't use them unless there was a real need.
The toilet unit was a tallish (guess about 4ft) galvanised steel tank with the appropriate seat and cover on top, it was, in fact, a very good unit, having an air system to keep the biological activity going in the contents and free of smell. Fortunately the aeration and bubbling stopped when you lifted the cover to use it. These things were on simple four wheel chassis and parked in short sidings with a canvas screen around them with an air driven light for those who couldn't go by feel alone, but I recall that reversing up a couple of ladder rungs with overalls around the ankles, they wern't the easiest of things to use. Now, a mine has a lot of safety instructions designed to be flouted, especially like not to carry explosives and detonaters on the battery boxes, then driving at breakneck speed down the driveways without the loco lights on (the battery might not last until the end of the shift and high production is a high pay packet, the rails guided the train, so lights were not really required).
On Saturdays these toilets were taken to the surface to be emptied and suddenly a whole new breed of superhuman miners took over. The train loco went through the level with lights on full, horn blaring and at less than a walking pace. In case something went wrong, there would be one or more empty vee skips as idlers between the loco with it's exposed driver and the toilet wagon and often another at the rear. Once at the shaft, the thing was put in the cage for a slow gentle ride to the surface and a trip to the main sewage works. To be honest, it's not the sort of thing I took pictures of - sort of wish I had now, and at present the pics from this era are hiding. I'll try and find them dreckly.
Steve