As asked earlier, how do they prevent an enormous loss of liquid via seepage?
From my understanding, isn't that was the ice walls are designed to accomplish? I understand that that would create a walled structure leaving the bottom open. I assume though that the shale and rock would maybe act as a liner on the bottom? I'm sure the engineers thinking of this already figured that out.
"As asked earlier, how do they prevent an enormous loss of liquid via seepage?"
I don't know. Sorry. I'm sure the pumping system is in place around the localized heating to get the majority, however.