For the Foundry malfunction, I suppose you found the note which explains the "emergency protocole"? Here is the solution:
Gaz compressor up
Deoxydation process down
Thermic exchange generator up
Ignifuge injection up
Micro-pulse timer up
Did you get the flamethrower?
Also, there is a chest to dig in the Gardens of Madness, along with two other secrets. One is easy (lever/secret door). The second one is less obvious, it is about lighting the lanterns in the right order...
In the Power Plant, did you understand the hint "He watches your back" ? Unfortunately, once the power plant destroyed, you won't be able to solve this one.