Public Utility Uses Re-Injection Of Treated Arsenic Contaminated Water To Reduce Underground Plume Leaching

In December 2009, Siemens was contacted to treat groundwater for arsenic removal to achieve a 1 ppb goal. The 1 ppb goal limit is equivalent to 10 percent of the current drinking water standard in California and represents the first request at this low treatment goal in the US. The treated groundwater is reinjected on the property to reduce the size and mass of the contaminated plume leaching from the property. The Siemens system was requested on an emergency basis and employs a once through adsorptive media treatment which was selected to reduce levels from as high as 65 ppb to the 1 ppb goal. To achieve the lower standard at the 80 gpm continuous flow rate required a system with three media tanks operating in series.

The project was initiated as an emergency treatment requirement and later was modified as a permanent solution to increase the system flowrate. Additional expansion followed the permanent installation. Siemens provided a complete, turn-key service solution which included pretreatment equipment, storage tanks, exchange vessels and media.

When the media capacity is exhausted, Siemens local service technicians remove spent media/vessels from the site and replace them with fresh tanks containing new media. The vessels are transported to our company-owned RCRA permitted and licensed TDSF treatment facility for compliant treatment and recovery of metals. The system’s modular design allows for easy exchange and service with minimal disruption to daily operation.