EPA finalized national primary drinking water regulations for six per- and polyfluoroalkyl substances (PFAS): perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA), and perfluorobutane sulfonic acid (PFBS); the Agency also finalized a Hazard Index of 1 as the maximum contaminant level goal and maximum contaminant level for any mixture containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS.

NOAA announced the availability of final evaluation findings for seven state and territory coastal management programs and four national estuarine research reserves under the CZMA. 

The Mine Safety and Health Administration amended its existing standards to better protect miners against occupational exposure to respirable crystalline silica, a significant health hazard, and to improve respiratory protection for miners from exposure to airborne contaminants.

The National Highway Traffic Safety Administration proposed to establish two new federal motor vehicle safety standards specifying performance requirements for all motor vehicles that use hydrogen as a fuel source.