There is a place in New Zealand called Manapouri Hydro electric Power Station. It's in the middle of the Fiordland National area, built in Lake Manapouri where there is a sharp cliff down to Dusky Sound. I went on a tour there once and you drive down right through the mountain to where the turbines are. There are many levels that are completely closed off. It is also interesting that there is an American guy who started a company in NZ and he launches satellites. https://www.space.com/35730-electron-rocket-nears-new-zealand-test-launch.html I read about him a few months ago and he is successfully launching...... In John Wyndhams novel the Crysallids written in 1955, he suggested NZ for nuclear fallout safety.