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INFORMATION SHEET BROWN SAND, INC. , MOSSDALE ASSOCIATES, LTD. MOSSDALE RANCH AGGREGATE SAND EXCAVATION AND PLANT SAN JOAQUIN COUNTY Brown Sand Inc. will be operating an aggregate sand excavation and processing plant on 303 acres of land owned by Mossdale Associates, Ltd. , adjacent to the San Joaquin River, south of Interstate 5 crossing of the river, near Manteca. Brown Sand, Inc. will be excavating an anticipated 400,000 cubic yards per year of near surface sand deposits from approximately 185 of the 303 acres. The surface soils and sediments lying above the water table will be excavated using a five- yard loader, and excavator, and a caterpillar-type tractor. Excavated material; will be loaded onto rubber tired scrapers and delivered to the plant. Below the ground water table, a bucket type dredge will be utilized to excavate sands to a depth of 55-60 feet below ground surface. The dredge will float on the surface of the dredge pond and deliver the dredged sand to a washing and screening plant via a conveyor belt or a slurry pipeline. No dewatering of the excavation will be necessary. Initially, the wastewater from the sand washing operations will be discharged to a sedimentation/recycle pond. A coagulant and a flocculant will be added to the washwater to enhance settleability of the fines. Concentrations of these chemicals in the 3.6 million gallons per day of washwater will be 1-3 ppm. These chemicals are designed to be bound to the sediments and should not pose a significant threat to ground water quality. The sedimentation/recycle will be monitored for the chemical constituents found in the coagulant and flocculent. It is anticipated that eventually the washwater will be discharged to the excavation without the addition of chemicals. Fines generated will be periodically removed from the sedimentation pond and placed next to the pond for decanting. Ultimate deposition of the fines will be next to the excavation area. The site will be designed to have surface water runoff contained on-site. All chemicals and steam cleaning operations will be designed to be contain all waste material and storage and operating areas, and prohibit storm water from contacting potential contaminants in those areas. Wastewater sedimentation/recycling ponds will be designed to contain washwaters, sediments, and rainfall from a 24-hour storm with a return frequency of 100 years. Ground water samples have been analyzed from an existing ground water monitor well . The first round of sampling has found the ground water to have a pH of 8.0, a TDS concentration of 985 mg/1 , a chloride concentration of 262 mg/1 , an iron concentration of 10.75 mg/l , and a manganese concentration of 1 .25 mg/1 . The iron and manganese concentrations are above their Secondary Drinking Water Standards (SDWS) of 0.3 and 0.05 mg/1 , respectively. The SDWS are established for taste and esthetic values. AMM ,