At SLAC National Accelerator Laboratory, rainwater collects in many types of secondary containers installed around electrical equipment, storage tanks, chemical storage areas, and other structures. As of 2014, these containments undergo monitoring for rainwater accumulation and are evacuated by a vacuum truck with a 2,000-gallon tank. The water is processed through a nonhazardous water treatment unit, which uses activated carbon canisters to remove organics and solids and is equipped with a 100-micron prefilter. The water is then discharged into the reservoir of Cooling Tower 1701 for reuse in cooling operations. Clean wastewater from construction projects and pipe testing is also being collected and filtered for use in the cooling towers, or discharged to landscaping for irrigation during the dry summer months.

SLAC’s other wastewater is treated off site at Silicon Valley Clean Water for discharge. The Environment, Safety and Health Division formed an industrial wastewater working group to address issues and information gaps related to reducing sanitary sewer discharges. In addition, the SLAC Water Balance Equation was updated to more accurately reflect water usage and wastewater generation. Sanitary sewer and storm drain discharge will continue to be monitored with the intent to minimize sewer discharge and increase water reuse where appropriate.