That may depend on the filter you're using. Berkey has 2 types of filters - the black carbon ones that come with it normally, and white ones that are made for heavy metals, etc. They are marketed for flouride.All this talk of wells has me creeped out now I have a shallow well not sure how deep it’s a sand point ……. But I run all my drinking and cooking water through a Berkey water filter system…. Does that do the trick for herbicide / pesticide issues until spring when I can afford to install a deeper “real” well? Or should I switch to bottled water…….. ugh. Out of sight out of mind doesn’t work for me.