SITE INFORMATION AND CORRESPONDENCE CASE 2

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WASTE DISCHARGE REQUIREMENTS ORDER NO.R5-2002-0071 -7- CALIFORNIA NATURAL PRODUCTS WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY 42. The depth to groundwater is approximately 10 to 15 feet bgs and the groundwater gradient is reportedly to the northwest and west, although locally, groundwater depth and flow may be influenced by local pumping and irrigation patterns. 43. The average analytical results for groundwater samples collected from May through September 2001 from Wells W-1 through W-4, and L-1 through L-3 are presented below. Earlier analytical data is not presented because it is considered to be low quality and therefore unreliable. 17.6 Acre Area Proposed 16.0 Acre Area Analytes Units Average (W-1 throu W-4) Average (L-1 through L-3) pH Std. 7.26 7.83 TDS mg/1 1,492 512 NO3 as N mg/1 39.6 20.8 TKN mg/1 ND (0.50) ND (0.50) TDS denotes Total Dissolved Solids. NO3 as N denotes Nitrate as Nitrogen. TKN denotes Total Kjeldahl Nitrogen. 44. As indicated in the table above, the average TDS concentration in the groundwater below the current land application areas is almost three times higher than that of the groundwater below the area that has not yet been used for land application, and the average nitrate (as nitrogen) concentration in the groundwater below the current land application areas is almost twice as high as that of the groundwater below the area that has not yet been used for land application. This data, coupled with the reported groundwater gradient to the northwest, indicates that groundwater below the 17.6 acre land application area and 9.2 acre landscaped area may be impacted by the discharge of wastewater from the facility. It is noted that none of the wells in the 17.6 acre land application area are located upgradient of wastewater application activities, therefore, the Discharger must install additional background wells. A similar situation will exist at the 16.0 acre land application area once wastewater application begins. 45. These WDRs require monitoring of shallow groundwater conditions, including background water quality and direction of groundwater movement throughout the year. 46. The Discharger has substituted certain chemicals in the processing facility with more environmentally acceptable alternatives (i.e. potassium hydroxide for sodium hydroxide, and nitric or phosphoric acid for pH neutralization) resulting in wastewater with more plant nutrients. This approach should result in lower TDS percolate concentrations when applied to cropped land application areas. In addition, the Discharger began growing crops on the 17.6 acre land application area in the year 2001; both actions should lead to a reduction in TDS and nitrate concentrations beneath the 17.6 acre land application area. If reductions are not observed, the Discharger will have to reduce the groundwater impacts through other alternatives. SITE SPECIFIC CONDITIONS 47. Local land use consists of industrial,residential, and agricultural operations. The topography of the surrounding area is level.