[Eupalinos of Megara appears out of a time portal from ancient Ionia] Wow, you guys must be really good at digging tunnels by now, right?
[Eupalinos of Megara appears out of a time portal from ancient Ionia] Wow, you guys must be really good at digging tunnels by now, right?
Why would a grout accelerant burn people?
The Lime in Portland cement.
Linky
Guessing it is an oxidizer
Cements and other pozzalanic materials also tend to be very alkaline. Industrial dumping of waste concrete can create a huge environmental hazard.