On March 9, 2026, Environmental Protection Network submitted formal comments to EPA on the proposed National Primary Drinking Water Regulation for Perchlorate. EPA is proposing a maximum contaminant level goal (MCLG) of 20 μg/L and is taking comment on maximum contaminant levels (MCLs) of 20, 40, or 80 μg/L. EPA does not believe the benefits of this proposal outweigh the costs of its implementation but is required to publish MCLs and MCLG. EPN asserts that EPA has done inadequate analysis of the uncertainty factors involved in setting the MCLG. EPN points to data that would support a much lower MCLG and recommends that EPA evaluate the timing of peak perchlorate occurrence, coordinate with states with existing perchlorate monitoring requirements to minimize administrative workload on public water systems, and consider treatment options that could result in significant cost savings while protecting human health.
EPN Comments on National Primary Drinking Water Regulation for Perchlorate
