Drinking water utilities and the chemical sector have filed their opening briefs in their suits challenging EPA’s landmark PFAS drinking water rule, charging that the agency violated legal mandates when it evaluated the rule’s costs and benefits, bypassed procedural requirements for standard-setting, made novel use of a formula to regulate mixtures, and failed to use up-to-date occurrence data. “The themes of EPA’s rulemaking are apparent -- hastiness, novelty, and inadequate data,” say American Water Works Association (AWWA) and Association of...