EPA proposed drinking water limits for a rocket fuel ingredient to satisfy a court order, in a rare example of the Trump administration setting a new regulation despite its deregulatory focus.
Monday’s proposal would set maximum allowable levels for perchlorate, a substance that interferes with thyroid functions and can hamper the brain development of fetuses. Used in explosives and rocket fuel, perchlorate is estimated to taint the tap water of millions of Americans, with people living near military sites most at risk of exposure.
The proposed legal limits exceed the concentrations environmentalists have previously suggested as safe, raising questions about whether the new regulation will end — or spur additional — litigation.
The agency proposed a maximum level in tap water of 20, 40 or 80 parts per billion and a nonenforceable maximum contaminant goal of 20 parts per billion. By comparison, California’s drinking water limit for perchlorate is 6 parts per billion, while the maximum limit in Massachusetts is 2 parts per billion.
