On July 1, 2014, the State Water Resources Control Board - Division of Drinking Water standard for hexavalent chromium (chromium-6) took effect. California is the first state in the nation to establish a regulation specific to chromium-6, demonstrating a proactive response to a public health concern.
The new standard, or maximum contaminant level (MCL), is 10 parts per billion (ppb). To put that in perspective, one ppb is one drop of water in a full Olympic-size pool.
Where Chromium-6 Is Found
Chromium-6 tends to be predominately found at highest levels in groundwater because of industrial contamination, or naturally occurring mineral deposits. Concerns about the health impacts of chromium-6 have been highlighted by contamination levels measured in cities like Hinkley, California.
Chromium-6 has not been a concern in CCWD's service area, However, CCWD has actively participated in efforts to develop testing to monitor for the presence of chromium-6 in drinking water. Historically, water quality tests looked at total chromium and did not differentiate down to the molecular form.