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1 0 1 P F� 1 1 1 1 H, 1 1 1 P 7 2.26 Processing and Storage of Materials. Facility processes are designed to manage inorganic wastes generated typically by electroplaters and printed circuit: fabricators. The Facility will manage these materials by rendering them safe for recovery and reuse or for later disposal in secure landfills. Typical wastes managed by the Facility are: heavy toxic metals such as copper, chromium, nickel, cadmium, zinc, and lead; cyanide in caustic solution; metal hydroxides precipitated as low solids sludge, and liquids; and oily waters, such as cutting liquids used during metal milling processes. All organic materials received will remain as drummed, stored materials awaiting consolidation and transhipment to appropriate treatment and/or disposal facilities in other states. 2.261 Ion Exchange. Ion exchange is known in households as water softening. Used in an industrial process, it is a means of scavenging or removing ions in solution, based on a chemically active resin or small plastic bead which attracts appropriate ions in solution to its surface and chemically binds that material. When the ion exchange canister is saturated or full, it is replaced in the generating plant with a fresh canister. The saturated canister is shipped to the Facility. Upon receipt at the Facility, the canister is segregated by the resin type: cation or anion. The cation resins remove metals from water solutions and the anion resins remove chlorides, sulfates, phosphates, and other typical negative valence anions. The saturated canisters are regenerated at the Facility by either flushing with a concentrated acid or alkali solution, depending on the resin type. This effectively reverses the chemical reaction at the surface of the resin bead and flushes the bound material out of the canister into a collection tank. The canister is regenerated and put back into the inventory for later shipment to a generator's plant. 2.262 Chromium Reduction. Chromium exists in the hexavalent form in etching, plating, and chromating baths and rinse waters. Hexavalent chromium is much more reactive and toxic than other form of trivalent chromium. It must be reduced to the trivalent form in order to be less toxic and prepared for later hydroxide precipitation, if that is the form of disposal. The reduction reaction is accomplished through the addition of sodium bisulfite in an acid solution. It is performed in a simple mixing tank with a mixer. 2.263 Cyanide Oxidation. Cyanide destruction or oxidation is required to remove the material from solution prior to precipitating the metals that remain