I gather even artesian wells can contain these chemicals, which get pretty much everywhere. On the other hand, based on the article you linked to, if something

I gather even artesian wells can contain these chemicals, which get pretty much everywhere. On the other hand, based on the article you linked to, if something like a Berkey filter is sufficient (I have doubts about their testing, but whatever) the cost is probably not prohibitive. Assuming there's something as effective as a Berkey which can handle a more practical flow of water, but at the same cost per volume of water handled.