In an April 11 letter to new EPA Assistant Administrator for Water David Ross, AMWA reiterated its previous comments on the agency’s work to develop a Maximum Contaminant Level Goal (MCLG) for perchlorate.
In particular, AMWA highlighted concerns with the methods and model shown in the draft report, Proposed Approaches to Inform the Derivation of a Maximum Contaminant Level Goal for Perchlorate in Drinking Water, stating: “[t]he association has concerns with the methodology of the model and its use to extrapolate possible neurological outcomes in children. AMWA is not certain that the model is precise and reliable enough.” The letter also stated that AMWA “is concerned with the possible biases that are introduced by using the model’s output with already existing neurodevelopment data from the literature in order to make conclusions on the impact of perchlorate on neurodevelopment.” AMWA attached the association’s previous comments, submitted to EPA in November in response to a public notice, where specific issues and concerns with the model and methodology were detailed.
The letter concluded by noting that the report “sets a worrying precedent for regulatory determination decisions in the future.” EPA has until October 31, 2018 to propose a drinking water regulation for perchlorate and a deadline of December 19, 2019 to finalize it per consent decree.