CA to receive first-of-its-kind hex chrome treatment system for drinking water

Envirogen Technologies recently announced the successful startup of a high-efficiency ion exchange system for the treatment of hexavalent chromium in drinking water supplies for California Water Service in Salinas, Calif.

KINGWOOD, TEXAS, July 13, 2015 -- Envirogen Technologies Inc., an environmental technology and process solutions provider, recently announced the successful startup of a high-efficiency ion exchange (IE) system for the treatment of hexavalent chromium (hex chrome) in drinking water supplies for California Water Service (Cal Water) in Salinas, Calif.

This is the first permitted full-scale system to go online for treating hex chrome since California's Division of Drinking Water (DDW) released a new maximum contaminant level (MCL) of 10 µg/L (10 micrograms per liter) in July of 2014. The IE system will treat groundwater sourced from a well in the Cal Water system to be more than 20 percent lower than the MCL.

The selection of Envirogen's technology was based on a system design that offers a high level of reliability, low waste and disposal rates and the lowest lifecycle cost. The system was designed, manufactured, installed, and started up in less than 90 days from project go-ahead. A second IE system is planned to come online for Cal Water this summer. These systems represent the eighth and ninth systems provided by Envirogen and in operation for Cal Water to treat drinking water -- with the previous systems treating nitrate and perchlorate.

For Cal Water, the IE system features a multi-vessel bed design that operates in a staggered configuration, blending the water from each vessel and producing a consistent treated water quality. Depending on the flow range, between eight to 13 vessels are online at any time, with three vessels in regeneration or standby. These systems utilize Envirogen's patented, counter-current, cascading bed regeneration process to minimize waste, resulting in one bed volume of waste per regeneration cycle and allowing waste rates as low as 0.01 percent.

The largest component of the operating cost associated with most IE systems is waste handling. For hex chrome treatment, the IE waste brine may be a Federal hazardous waste (i.e. Cr > 5 mg/L) that is expensive to dispose of directly. Envirogen's solution for Cal Water is a Brine Processing Unit (BPU) that converts hex chrome to a less hazardous, trivalent chromium that is then precipated using an NSF-61-approved coagulant. The result is a non-hazardous liquid brine waste and a small volume of 2 percent solid waste. The process units -- IE and BPU -- were containerized for rapid deployment at the Cal Water wellhead, allowing a small facility footprint.

See also:

"Envirogen provides water solutions for North American food & beverage industry"

"Envirogen secures financing for environmental treatment projects"

About Envirogen Technologies, Inc.

Envirogen Technologies, Inc. is an environmental technology and process solutions provider that combines experience in water and vapor phase treatment with process development expertise - delivering long-term, guaranteed solutions in a broad range of treatment and process-related applications. In industrial markets such as mining, hydrocarbon processing and chemical processing, Envirogen also specializes in process water treatment, byproduct recovery and chemical purification. For more information, visit


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