Rockets do often have some kind of exahust pit just below them, this one just happens to be filled with nuclear waste. I know its a little strange but then pretty much all the launch locations in TF2 don't make logical sense, I mean how the hell did they get a saturn V sized rocket into the middle of dustbowl?? build it in situ?? I think not, or how about those huge rooms in well, no one would launch a rocket of that size in that nice clean room it would just ruin the room, not to mention the structural integrety of the building. And in goldrush, theres a track leading right up to a pit of neatly stacked nuclear waste, they certainly didn't tip the barrels in so how did they do it? theres no door into there.. How about in turbine, those containers in the middle room, how did they get there, there aren't any doors bigg enough to take one of those and a lorry, and theres no crane or anything. Gravel pit - who would build tunnels that end half way up a cliff?? even if they aren't part of your complex you'd still make sure they ended at ground level or make a ramp up to them. I'm just trying to make it clear that there are a lot of unrealistic things in TF2 that aren't just because of its cartoony style and they you need to take things with a pinch of salt.