These guys said dams are probably the most dangerous they do and they had basically been all over the world doing anything.
Speaking of tubes. I worked for a company who did a lot of work on hydro plants. One of the labor foreman was telling me about a job where they sleeved some old riveted iron pipe with hdpe and then grouted the gap. They did 2 identical dams, and one took was less grout, for whatever reason they had to get it fixed right away. These were near the Rubicon in the Sierra, so ~5' of snow at the time.
They flew in a helicopter and had to jump out and shovel the pad just for him to land. The pipes had pigs in the top since the lake was full, so they had to climb in from the bottom. The plan was to drill holes every so often and then pump grout into whatever void they could find.
They finish up, and start shimmying out, when dude on the bottom says he's stuck? Wtf, do you mean you're stuck, just get out we gotta go. Uh, no I'm stuck, I think the pipe is collapsing
first dude was able to wiggle out, but is much slimmer than 2nd dude. So he's thinking the top is 5' of snow and ice, and there 8s no way he's fitting through the small gap. Luckily they had the safety line and 3 guys had to yank him out.
About this time, the pilot is telling them they need to leave now, the storm was lowing the ceiling that the helo can fly at. They start trying to clean up and he says, no I mean now, I'm leaving with or without you guys. So they end up leaving with generators running, grout in the pumps, ect.
They take off over the lake and end up almost end up in the trees. Guy banks left and they end up literally having to take the road down, and the hwy 50 down, because they couldn't pull over the tree line.
All this was the bigger guys first week
Ive never thought I was claustrophobic, but that story pretty much made me feel like I am.
