AWWA MEMBER ALERT

Court Strikes Down Regulation –  Maximum Contaminant Level of 10 parts per billion (ppb, also micrograms per liter) for hexavalent chromium (Cr6)

On May 5th the Superior Court in Sacramento issued its final ruling in a case challenging the regulation that set a Maximum Contaminant Level of 10 parts per billion (ppb, also micrograms per liter) for hexavalent chromium (Cr6). The court ruling struck down that regulation for the time being, and sent it back to the SWRCB for a better analysis of the economic feasibility of an MCL at different levels. In reaching this decision the court rejected many of the responses of the California Department of Public Health (the agency responsible for setting state drinking water regulations at that time) to comments raising concerns about the economic feasibility of meeting the MCL at that level, especially for small water systems lacking economies of scale. This was a major issue raised in a technical analysis completed for the Section, jointly with the Association (AWWA), the Association of California Water Agencies (ACWA), and the California Water Association (CWA).

The responsibility for a fresh look at the Cr6 regulation now resides with the Division of Drinking Water, under the final authority of the State Water Resources Control Board. In correspondence with the Section, SWRCB Deputy Director and head of DDW Darrin Polhemus indicated it will take some weeks for a new regulatory process and schedule to be announced. Meanwhile, drinking water systems planning or already constructing new facilities to meet an MCL of 10 ppb must decide how to proceed, with very little guidance except that at some point there will be a regulation for Cr6; whether it will be changed from the previously adopted one is anyone’s guess.

On a related front, the Office of Environmental Health Hazard Assessment (OEHHA) is expected to complete sometime this year its 5-year review of the Public Health Goal for Cr6. The PHG is currently set at 0.02 ppb. That review was initiated late in 2016, with an abundance of new scientific research about health effects of Cr6. The most recent publicized activity on this was OEHHA’s extension of the comment period for this review until December 13, 2016.

The Section’s Safe Drinking Water Act Committee will continue to monitor and report to members on new developments related to Cr6 as a drinking water contaminant.

Complete Court Ruling
AWWA Section’s Safe Drinking Water Act Committee

For more information, please contact The Section Office.

CA-NV AWWA |10435 Ashford St., 2nd Floor | Rancho Cucamonga, CA 91730 | Phone: (909) 481-7200 | Fax: (909) 481-4688