The agency released this draft
after working on the issue for more than a year.
While the current state standard pertains to total chromium and is set at 50 parts per billion (ppb), the new draft standard will specifically address hexavalent chromium and establish a MCL of 10 ppb. The new draft MCL will also be the first primary drinking water standard for hexavalent chromium promulgated by any state or federal agency.
Hexavalent chromium is present in a large number of drinking water sources and can be found naturally in groundwater as well as from industrial pollution, as it was made famous by Erin Brockovich and the community of Hinkley. According to CDPH, most detections of hexavalent chromium have occurred in Los Angeles, San Bernardino and Fresno counties. However, elevated levels of hexavalent chromium have been detected statewide.
Water agencies throughout the state have been working to reduce hexavalent chromium with some success; however, the cost to treat drinking water with elevated levels of hexavalent chromium may be considerable for some jurisdictions. In its Initial Statement of Reasons
, CDPH estimated that the total statewide annualized cost of complying with the proposed MCL of 10 ppb is approximately $156 million. The Association of California Water Agencies
(ACWA) in a comment letter (regarding the proposed MCL), noted that it felt CDPH had underestimated the number of affected systems and had severely underestimated the statewide annualized cost of compliance with the proposed MCL, which it believes to be significantly higher at more than $600 million. ACWA issued this letter
on Oct. 10, 2013.
Many of these costs will be reflected in increased water rates, which can impose a real hardship on residents. Some communities, like the city of Watsonville, have noted that their water bills could increase 78 percent to cover the more than $26 million cost to install a treatment system and maintain ongoing operations to meet the proposed hexavalent chromium MCL of 10 ppb at their municipal wells. The city of Glendale municipal utility oversaw a study identifying and implementing drinking water treatment technologies for hexavalent chromium that spanned 10 years and cost more than $9 million. In February, the Glendale City Council approved additional grant funds to continue their research on hexavalent chromium.
While communities grapple with how to fund treatment of hexavalent chromium, the CDPH will continue work on the draft MCL. A final, enforceable MCL is expected sometime this spring, with the regulation being effective immediately. However, a jurisdiction will not be deemed out of compliance until several tests confirm hexavalent chromium levels are above the MCL over a 12–16 month period. Additionally, funds may be available in the Safe Drinking Water State Revolving Fund
to assist local agencies with compliance.