Perchlorate: Revisiting Recommendations for New EPA Rules

Key Takeaways The US Environmental Protection Agency has released a preliminary drinking water rule for perchlorate that could set maximum contaminant levels in drinking water at 20, 40, or 80 μg/L. Perchlorate contamination, often a localized groundwater issue, has been found in Colorado River water as a result of legacy industrial contamination. Perchlorate also forms during the storage of bulk hypochlorite solutions, though it is unlikely to be a driver for change at drinking water utilities. Extensive guidance has been developed from past studies and is summarized here, considering the new preliminary drinking water rule.