S. 3590 would authorize appropriations for the Environmental Protection Agency (EPA) to fund 17 grant programs aimed at improving the quality of drinking water. The bill also would direct EPA to issue a national primary drinking water regulation, which would establish legally enforceable limits on concentrations of certain perfluoroalkyl and polyfluoroalkyl substances (PFAS) in drinking water. In addition, S. 3590 would direct EPA to study access to affordable supplies of drinking water, issue new guidance and testing protocols for lead contamination, and report on new technologies to enhance the treatment, safety, and affordability of drinking water.