Chromium 6

 

 

Work on the District's Chromium 6 Removal Treatment Facility and Improvements are underway. Pipeline construction in the Seacape and La Selva Beach will be late June-September 2016.

What is Chromium 6?

Chromium 6 is naturally occurring metallic element found in rocks, soils, plants and animals. The most common forms are Chromium 3 and Chromium 6. Chromium 3 is found in foods and is an essential dietary nutrient. Chromium 6 can be toxic if consumed in large amounts.

The Chromium 6 detected in our water supply is naturally occurring. There was no industrial spill or discharge. Scientists have estimated that up to 80% of the drinking water sources in the United States could have Chromium 6.

Are there regulation requirements on Chromium 6?

Since the 1970s until 2014, California enforced a drinking water standard for total Chromium (which includes Chromium 6) of 50 parts per billion (ppb). That level is more stringent than the federal standard of 100 ppb.  Note: One part per billion is about one drop in an Olympic-size swimming pool.

The California Division of Drinking Water adopted a new drinking water standard for just Chromium 6 in July 2014 of 10 ppb. Water suppliers in some situations have up to five years to comply with the new standard.  This is the first standard for Chromium 6 in the nation.

For more information on Chromium 6 in drinking water please visit the Division of Drinking Water http://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Chromium6.shtml.

What We've Done to Address Chromium 6

The District has been and continues to be very proactive to meet the State’s upcoming standard.

  • Four wells (Altivo, Seascape, San Andreas, and Bonita) have levels above 10 ppb.
  • Seascape and Altivo Wells were switched to standby for use only in an emergency.
  • We conducted a successful pilot treatment project with grant funding by the Water Research Foundation from April to August 2013– Read complete report published in September of 2014.
  • We demonstrated our local water could successfully be treated to remove Chromium 6 to the new CA standards.
  • On August 12, 2014 the Board of Directors set a treatment goal of 2 ppb for Chromium 6 where treatment is implemented. This is 1/5 of the State Standard of 10 ppb.
  • We began operating a temporary treatment plant in October 2014.

What We're Currently Doing

  • We have been successfully meeting the new drinking water standard for Chromium 6.
  • We are currently constructing components of the permanent full-scale treatment plant that is a Proposition 84 partially grant-funded project. The overall effort includes construction of a new treatment facility for chromium 6 removal at the District's Bonita well site, a new raw water pipeline from the District's Seascape well to the San Andreas well to deliver water to the new treatment facility, and replacement of groundwater pumps at the Seascape, Bonita and San Andreas wells. A new sewer line will also be constructed to connect the treatment facility to the existing County of Santa Cruz Sanitation District sewer system.
  • We anticipate this full-scale facility to be on-line in 2018.