ECS Chains

Hey guys,
This one is mostly directed at Michael, but I'm sure you'll all have
something to say about it.
In my implementation of the ECS Standards, I wanted to add a chain concerned
with Nuclear Power. Noticing that the standards had completely ignored such
an option, I've decided to throw this up for discussion: which three
cargoes(and three industries, if need be) should the Nuclear Power chain
replace. I'd prefer the Industries be directly related, since that would
remove any possible mess-ups which would occur from mixing ECS
Implementations.

Cheers,
WhiteHand