California Water News Daily Your Source For Water News in California
Last week the State Water Resources Control Board (SWRCB) formally proposed to set the maximum contaminant level (MCL) for hexavalent chromium in drinking water to 10 parts per billion (ppb).
SWRCB’s proposal included a three-stage compliance schedule that would provide small water systems with more time to acquire and implement the necessary water treatment technologies to meet the standard. Systems with over 10,000 service connections would have two years to comply with the new limits, while systems with under 1,000 connections would have four years.
“It has been a challenging path to a maximum contaminant level for hexavalent chromium that makes sense for California, but we are confident that the board can set a level that is more protective of public health than the current one for total chromium and that is economically feasible for our state’s diverse public water systems. Ultimately, protecting public health means having a standard that most systems can achieve,” said Darrin Polhemus, deputy director for the Division of Drinking Water.
The prior MCL for hexavalent chromium was invalidated in 2017 when a court ruled the state did not adequately document if it was economically feasible for water systems to implement. The only MCL currently in place is for total chromium, which is all chromium compounds present in water, including trivalent and hexavalent chromium. This level is set at 50 ppb in California and 100 ppb federally.
The formal period for public comment on the proposed regulation and the draft environmental impact report concludes on Aug. 4. A public hearing is scheduled on Aug. 2.
If adopted by the board, the new MCL would likely take effect sometime in 2024.
