>>723387170
>If there are other contaminants, they don't seem to be making anyone sick.
Seeing as most normal humans and life has already mutated this is par course. How will the kids of those people end up in the far future is another issue. For all you know light FEV and radiation adaptation humans have acquired now will ruin human form in near or far future, so making a mass-proceessing plant is a good idea.
More importantly, there can be military contaminants, delivered in the future by any potential enemy, so a system that makes pure drinkable water (and all sorts of desired chemicals) on demand with 100% guarantee is an excellent long term investment, both on its own, or in conjunction with, say, poisoning all other wells.
Dehydration, that I can't argue. I don't remember F3 so well at this point.
As for Nee-san (heh), Dr. Li is implied to have went, or went back to the Institute I think?
Either way you can induce that the purifier is too ambitious, so without a man with a particular set of skills, both technical and leadership, the project becomes unviable or unreachable due to the Enclave. Once it is active it is complete.
Megaton I too don't recall. I recall a hobo near a door, but the rest? Nah.