Removing Nitrates from Groundwater

Envirogen Technologies (USA) announced today the successful start-up of an ion exchange system for California Water Services, Salinas District (Cal Water) to remove nitrates from groundwater at the District’s 65-01 well site. The system is the seventh turnkey drinking water treatment system installed for Cal Water by Envirogen in the past decade, and will operate under a 10-year “technology+services” agreement that guarantees system performance and manages operating costs for the life of the contract. The cost to Cal Water will be based on volume and quantity of treated water. In addition to guaranteed performance, the custom-designed ion exchange system will generate low waste rates, maximize water recovery and allow the District to fit the new treatment capacity into a minimal footprint at the well-head.

According to Dr. Todd Webster, Director, Western Region, the new system demonstrates both the effectiveness of Envirogen’s patented ion exchange technology and the benefits of a “technology+services” approach for drinking water treatment. “Our partner-type relationship with Cal Water is a model case for the services approach for employing advanced technology for drinking water treatment. It also underscores our ability to meet the guarantees we put in place when we operate these facilities for our customers,” Dr. Webster said. “With seven successful projects over a decade working together, we are pleased that Cal Water has seen the benefits for its customer base of combining innovative technology solutions with a performance guarantee. We’ve been able to offer trouble-free operation and maintenance and significantly lower lifecycle costs,” he continued.

The nitrate removal system at Salinas District Station 65-01 is designed to handle 1.1 million gallons per day (GPD) of groundwater and will treat influent nitrate concentrations of up to 41 milligrams per liter (mg/L) down to less than 30 mg/L, incorporating a blending step for maximum operational efficiency. The 10-year services agreement, typical of Envirogen’s projects for Cal Water, provides guarantees of performance for the life of the asset, volume of salt consumption, volume of waste brine and finished water quality. The agreement covers all treatment equipment and associated connections. In addition, Envirogen conducted start-up and commissioning services and will be responsible for disposal of waste brine and full operation and maintenance of the unit for the 10-year period. Envirogen employs a full-time dedicated technician in the Salinas District to provide these services at all seven installations.

According to Mike Jones, District Manager for Cal Water Salinas District, the new treatment system will provide further support for the District’s service mission. "We are looking forward to having the new Envirogen plant operational,” Jones said. “This plant will strengthen our ability in providing our customers with safe, high quality water."

Cal Water is one of four subsidiaries of California Water Services Group, one of the largest investor-owned utilities in the United States (based on population served) with nearly 900 wells providing service to more than 1.7 million people. The Salinas District is located in a heavily agricultural area and is 100% dependent on groundwater sources, facing constant issues of both nitrate contamination and saltwater intrusion.