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FILE NO. 20-3978-01.WR6 K L E I N f E L D E R FEBRUARY 24, 1997 The raw sugar water or "juice" is purified by adding "milk of lime" and carbon dioxide to precipitate out the impurities. The milk of lime is produced by "calcining" the lime in the lime kiln and then adding water. The kiln is lined with a refractory material to withstand the high operating temperatures. The "used" lime is regenerated for reuse, and eventually the spent lime is disposed of at the lime ponds. Activated carbon is used to regenerate the lime. After the precipitation of impurities using lime, the raw sugar juice is passed through a series of filters to further purify it. Sulfur dioxide may be used to inhibit discoloration of the sugar. After filtering, the raw sugar juice is sent to the evaporators to thicken it. The thickened juice is then sent through a series of centrifuges which crystallize out the sugar. The syrup left after crystallization is known as molasses. The sugar is then dried in granulators and stored in the sugar warehouse or silos, or ground into powdered sugar. According to Mr. Tucker, the sugar produced at the Manteca plant was shipped off site in bulk for packaging at other facilities. The various heating and evaporating processes utilize steam produced by the boilers. The boilers on site were fired using fuel oil and/or natural gas. The heated water was cooled in cooling towers. Prior to the use of cooling towers, the hot water was discharged to a canal formerly located on the Spreckels property which traveled through the City of Manteca and discharged at the French Camp Slough. The cooling towers were installed in an attempt to reduce odors emanating from the plant, and in response to community concerns over the temperature of the water in the canal. According to Mr. Tucker, the cooling towers on site have never used hexavalent chromium as a scale inhibitor. Process water generated during the manufacturing process is discharged to the wastewater ponds. After sediment has settled out of the wastewater, the water is reclaimed for use on the crops grown on site. This waste stream included boiler blowdown, acidic and caustic wastes, laboratory wastes, and scrubber wastes. The-manufacturing plant equipment requires lubrication in the-form of industrial greases. Hydraulic oil is also likely used in the plant equipment and possibly the truck scales. The processing equipment is cleaned between the processing seasons or"campaigns"using acid or caustic solutions. Solvents were used in the machine shop and most likely within the plant for parts cleaning during repair operations. Cutting oils are also commonly used in machine shops. Maintenance activities at the Spreckels Manteca plant also included the repair of motor vehicles such as cars, and farm machinery, and the maintenance of a locomotive operated on site by Spreckels. The locomotive maintenance was not conducted at a specific location but was done on the tracks wherever necessary. 20-3978-01.WR6/207RE074.doc Page 7of17 01997.Kleinfelder./nc.