we have reusable mugs, but most people bring their own personal mugs.

We have bottled water down where I work, as there are no sinks or kitchen nearby on this floor. The problem I have with that is, my being a germaphobe, I wonder what sort of critters may be incubating in the holding tank before it's pumped out. And are they sterilizing the reusable bottles? can I trust the hands that handle them? *shiver*