We've barely figured out how to even detect a tiny portion of PFAS, and even then can't quantify it, we don't have any way of removing PFAS specifically, the best general purpose technology we have is reverse osmosis which is not economical. If it's in the ground water it will be in the drinking water.
What we need to do (as in the human race because this stuff just propagates around the globe), is to stop manufacturing them, immediately, because this stuff accumulates. The mentality of "shoot and ask questions later" in the name of industry, technological progress and "my wallet" needs to stop. Prevention is the answer, not more technology to fix a technology that should have already have been deprecated over a decade ago - and to be clear i mean all PFAS, until individual formulas can be proven ecologically and biologically safe.
To prevent history from repeating itself new chemicals beyond the thousands of PFAS should go through ecological and biological testing before allowing them to be manufactured at scale and released into the environment. In the same way we test products for human consumption, we need to learn that the environment is an extension of us, and if we disregard it, it will come back to bite us.