The City of Hollister and the Sunnyslope County Water District are continuing to implement the approved approach to comply with California’s new limits on the regulated compound Chromium-VI (Hexavelent Chromium) that is naturally occurring in our drinking water.
Chromium VI is a potential carcinogen and can cause other health problems. More information can be obtained by searching for Chromium VI on the internet.
In 2014, the California Department of Public Health approved a maximum contaminant level of 10 parts per billion (ppb) for Chromium-VI in drinking water, making it the only state to regulate the specific Chromium compound. For comparisons sake, that’s about 10 drops of liquid in an Olympic-sized swimming pools worth of water. It is the first state standard for Chromium-VI in the nation. The federal limit for total Chromium; established by the Environmental Protection Agency, is 100 ppb.
Test results from our wells are highly variable with some water indicating Chromium VI as high as 15 ppb, or 5 ppb over the mandatory limits.
What is Chromium?
All Chromium’s are naturally occurring elements found in rocks, animals, plants, soil, and in volcanic dust and gases. Chromium is present in the environment in several different forms. The most common forms are Chromium (0), Chromium (III), and Chromium(VI). No taste or odor is associated with Chromium compounds. Chromium (III) occurs naturally in the environment and is an essential nutrient. Chromium (VI) and Chromium(0) can also be byproducts of some industrial processes. The metal Chromium, which is the Chromium (0) form, is used for making steel. Chromium (VI) and Chromium(III) are used for chrome plating, dyes and pigments, leather tanning, and wood preserving.
What’s being done locally about it?
The West Hills Water Treatment Plant, which is part of the Hollister Urban Area Water Project (HUAWP), is under construction and will be operational by the end of 2017. The current plan; to address the Chromium-VI regulations, takes advantage of these already planned water treatment and water supply infrastructure improvements. As an alternative to a very expensive wellhead treatment to reduce Chromium VI levels in our drinking water, water from the West Hills Treatment Plant will be used to blend with well water, thereby saving millions of dollars now and into the future
Blending groundwater with high quality, treated surface water would be provided at existing municipal wells that show levels of Chromium-VI higher than state guidelines. The surface water will reduce the Chromium-VI to levels below these standards. State regulators have accepted this solution.
The West Hills Water Treatment Plant is a part of the HUAWP, a collaborative effort between the City of Hollister, Sunnyslope County Water District and the San Benito County Water District to improve water quality for drinking water customers, protect the groundwater basin, help meet wastewater discharge requirements, assist the agencies in developing a high quality recycled water and will allow the agencies to comply with the new drinking water standards. The HUAWP — approved in 2013 — was the most technically feasible and fiscally responsible solution to meet all these needs.
For more information on the Hollister Water Project go to: www.hollisterwaterproject.com or call (831) 637-8218, Ext 189
For more information on our drinking water in the Sunnsylope service area call (831) 637-4670, for City of Hollister customers call (831) 636-4377.
Shawn Novack is program manager for the Water Resources Association of San Benito County and submits a column to the Free Lance.
