Innovative Chromium 6 Treatment Exceeds State Requirements

New Treatment Facility Running Smoothly

Soquel Creek Water District’s innovative pilot facility to treat naturally occurring Chromium 6 continues to be on-track in successfully meeting the new state requirements. Over the next several weeks, the new treatment facility will be brought on-line treating up to 1,000 gallons per minute (gpm) of water by the middle of next month.

“The District has been ahead of requirements all along,” said Taj Dufour, Chief Engineer for the District. “Two wells that tested above the new state limit for Chromium 6 were removed from regular production long before the new standards went into effect in July. We are very proud to say that, on September 25, we received one of the first treatment facility permits in the State, and on October 10 we became among the first to successfully deliver treated water with reduced levels of Chromium 6 to our customers.”

The Chromium 6 detected in our water supply is a naturally occurring metallic element that is found in rocks, soils, and plants. There was no industrial spill or discharge. Scientists have estimated that up to 80% of the drinking water sources in the US could have Chromium 6.

In July, California tightened the Chromium 6 standard to a maximum of 10 parts per billion (ppb), well below the federal standard of 100 ppb and the California limit for total Chromium of 50 ppb. The standards were created because Chromium 6 may be harmful to human health if consumed in large amounts over an extended period of time. The District’s new treatment protocols will exceed federal and state standards to further protect the health of our customers.

“We’re confident that the quality of water we’re providing to our customers far exceeds even the new State standard. In fact, the District Board has set our goal to be one-fifth of the State’s requirement (2 ppb) for our water supply and we’re aiming to meet that,” Dufour said.

Four of the District’s 16 wells used for producing water have naturally occurring Chromium 6 levels higher than the new State standard. Over the next two years the full-scale permanent facility will be designed, permitted, and constructed, giving the District the option to treat water from three wells. The fourth well will remain in standby mode for emergency-use-only.

The pilot treatment system is located at the San Andreas well site near Hwy 1 and San Andreas Road. The facility showcases an innovative ion exchange technology that the District evaluated after being awarded grant funding by the Water Research Foundation in 2013. This pioneering research determined that the District could capture and neutralize the Chromium 6 with near-zero wastewater—ten times less waste than previous types of treatments—and at a significantly lower cost. “It’s the first time this technology has been used in the US, and the pilot results have been extremely impressive,” Dufour says.

The current facility is temporary until the District constructs a larger, permanent facility that will be operational by October 2016.

For more information: http://www.soquelcreekwater.org/water-quality/chromium-6

The Soquel Creek Water District is a non-profit, local government agency providing water to Capitola, Aptos, La Selva Beach, Opal Cliffs, Rio Del Mar, Seascape and Soquel. www.soquelcreekwater.org