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bead or sand blasting to remove scale, vapor degreasing to remove machining oils and other organics, alkaline cleaning to remove organics and for surface preparation, acid cleaning to remove oxidation and for surface preparation for plating, electroplating or electroless plating,, and'drying. Metals that are plated by WO include mainly copper, nickel, tin, rhodium, indium, silver, and gold. The process steps employed depend on the surface finishing specifications required of the research being performed and the application of the equipment being fabricated. MFO has traditionally used copper cyanide to plate parts, for example, in the high-voltage klystrons used in the two-mile linear accelerator at SLAC. Copper cyanide plating provides unique coating properties that are not readily replicated with non -cyanide copper plating baths. WO also uses its cyanide plating capabilities to support other national laboratory research throughout the country. Other laboratory researchers have also requested copper cyanide in their surface finishing specifications. After the parts are immersed in the cyanide bath, they are handled carefi�lly to reduce drag - out before the parts are immersed in a single -stage rinse water bath. The rinse water is treated on-site in batch mode in treatment tanks, using a conventional, two-step alkaline and sodium hypochlorite oxidation process to destroy the cyanide. After the cyanide destruction processing, the treated rinse water is forwarded to the Metal Finishing Pretreatment Facility (MFPF), a conventional pH adjustment4locculation- sedimentation pretreatment system of tanks, to precipitate and remove the copper and other heavy metal before discharging the treated water to the sanitary sewer. This cyanide rinse water is considered Category A because it is treated on-site and treated water's discharged to the POTW. The water is treated to meet discharge requirements of the POTW under the Clean Water Act. The copper is precipitated and collected in a settling tank in the form of metal hydroxide sludge in the MFPF. The sludge is concentrated in a filter press to form a filter cake. The filter cake is dried and packaged for shipment to an off-site, permitted treatment, storage and disposal facility. The copper cyanide treatment process, the MFPF, and the sludge dryJng processes are authorized to operate under the California Tiered Permitting program, MFO also works with gold and silver cyanide baths. Drag -out an d rinse waters are typically minimal, as the paras being plated'tend to be small. Asa result, drag -out and rinse waters are returned to the bath to conserve gold and silver use, eliminating the need for treatment of a rinse water waste stream. This approach is not as easily done with copper cyanide, since the parts can be larger in size and bath integrity can be more difficult to control. Hazardous Waste Management Ap roaches Source reduction measures implemented to date include careful monitoring of all the baths, including cyanide baths, to prolong their useful life. Alternative measures in the form of operation changes, such as using a countercurrent rinse bath, are not technically feasible due to space limitations. Some efforts have been made in September 1, 2015 SB14 Plan II -2