The Environmental Protection Agency (EPA) is proposing limiting the amount of harmful “forever chemicals” in drinking water to the lowest level that tests can detect. The chemicals have been used since the 1940s and their use is now mostly phased out in the US, but some still remain. The proposal would set strict limits of 4 parts per trillion for two common types of PFAS chemicals, PFOA and PFOS. Water providers will have to monitor for PFAS and the public will have a chance to comment. If the rules are finalized and imposed, many communities will learn they have been supplying drinking water with harmful compounds.