NRDC Agrees to Extension of Time for Perchlorate Rule

“Agrees” is brief wording for a headline, but a better description is that the Natural Resources Defense Council (NRDC) reluctantly decided not to oppose EPA’s request of the Court to delay by six months the date for proposing a rule to regulate perchlorate.  That will push the deadline for a rule proposal to April 30, 2019.

EPA made the decision to regulate perchlorate in 2011.  When EPA formally made that decision, it started a two-year time clock under the SDWA for proposing a rule. After EPA went well past the original date, with no rule in sight, NRDC filed a lawsuit to force EPA to take action.  A 2016 consent decree in that case required EPA to propose a perchlorate rule by October 31, 2018.  In the course of preparing the rule, EPA’s Science Advisory Board recommended that EPA take a novel new approach to derive the Maximum Contaminant Level Goal (MCLG) using a biologically-based dose-response model.  This modeling approach and the subsequent peer review process took six months longer than originally estimated which prompted EPA to request the extension.  Perchlorate will be the first completely new contaminant regulated since the 1996 SDWA Amendments.