Of course anything to do with safe drinking water or unsafe drinking water is relevant, but being relevant does not mean it belongs in the article. If it is relevant and integral to the article, in it should go, but as far as I can make out, it is not integral to this article, but to the fraccing issue in general. As such it should go into fraccing articles, and though it might well rate a mention in this article, all such a mention should comprise is that there are concerns and controversies on fraccing safety and desirability, with links to the most relevant fraccing articles. If you think that those articles do not mention the drinking water issues in sufficient detail and balance, go to the fraccing articles to make up the deficiency, not here. Otherwise we finally wind up with a separate (and very likely conflicting) fraccing discussion in every drinking water article for every major community in the Eastern US. And each of those will need its own updating and reconciliation etc. In short: a mess. Mention fraccing by all means. But do not explain, argue or enlarge at all in this article.  If you want to expound, feel welcome, but do it in articles where it will be appreciated. The principle has nothing to do with fraccing as such; it has to do with decent construction of articles. (OH, and in case you were about to ask about my personal interests in the matter and my connection with fraccing concerns, save yourself the trouble; I have none whatsoever, and I am not even American, nor do I live anywhere near the US.)