SITE INFORMATION AND CORRESPONDENCE CASE 2

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STAFF REPORT _2_ PAT MITCHELL AND CALIFORNIA NATURAL PRODUCTS LATHROP, SAN JOAQUIN COUNTY laser leveled and is surrounded by a berm approximately two feet high. The Discharger has recently added a pump station to allow reclamation of wastewater to 9.2 acres of landscaped area at the south warehouse. The wastewater will be sprinkler applied to landscaped areas. In the year 2000, wastewater discharge to the land application area ranged from 80,000 to 171,000 gallons per day(gpd). The City of Lathrop and the City of Manteca have permitted CNP to discharge up to 150,000 gpd of process wastewater and domestic wastewater to the Manteca wastewater treatment plant on an interim basis. CNP typically discharges approximately 50,000 gpd to the municipal system; discharge above 50,000 gpd incurs additional disposal fees. Since the installation of the pretreatment equipment in early 2000, a significant amount of wastewater(up to 84.4%) has bypassed the treatment equipment. Bypassing the treatment system resulted in high strength wastewater being discharged to land and caused objectionable odors. The Discharger reports that the bypass lines have been decommissioned. The Board received odor complaints about the Discharger's land treatment and disposal operations in October 1987, July 1997, July 1998, March 2000, and July 2000. As a result of the successful optimization of the treatment system equipment,wastewater discharged to the land application site is of much better quality than in the past. The anticipated wastewater quality is presented below: Constituent Units Untreated Wastewater Treated Wastewater Biochemical Oxygen Demand mg/l 2,205 100 Chemical Oxygen Demand mg/l 5,287 517 Electrical Conductivity µmhos/cm 1,550 1,681 Total Dissolved Solids mg/l 2,190 1,145 Fixed TDS mg/l 1,279 994 Total Nitrogen mg/1 49.3 37 pH Standard 8.6 7.8 Groundwater Conditions Groundwater monitoring has been performed since July 1988. However,much of the groundwater elevation data is poor quality and may not be reliable. The depth to groundwater is approximately 10 to 15 feet below ground surface(bgs). The direction of shallow groundwater movement is uncertain due to poor data quality. The average analytical results for groundwater samples collected since 1994 from the three wells in the land application area(MW 1,MW2,and MW3)are presented below. Also presented is the average concentration of analytes in samples collected from monitoring wells located at the processing facility(Wells A,B, and C)where land application has not occurred. Regular quarterly