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KLEINFELDER Nitrate Loading Study Comments Section 1.2 Page three of Study describes soil textures but does not describe how these soils will affect nitrate movement through soil. The near surface soils at the project site are moderately permeable (silty sand and sand with silt) and therefor(e are not likely to inhibit nitrate movement through the soil. Accordingly, a factor of 0.15�was selected as the percent denitrification of leach field effluent in the nitrate loading calculation in the referenced report. Section 2.3 Study must include verification that owner has made application for a wastewater discharge permit from the California Regional Water Quality Control Board in order to legally discharge wastewater into the retention pond. Notle Associates, Inc has prepared a study titled 'Technical Memorandum For Evaluation Of Wastewater Disposal', for the subject property owner in May 2005. As part of this study, recommendations are made for wastewater discharge improvements at the subject project site. It is our understanding the report has been forwarded to the Regional Water Quality Control Board and waste discharge requirements are pending. Section 3.3 Study does not include data nor discusses as to the constitutes of the 160,000 gallons/month of wastewater that enters the detention pond. The Study must discuss how nitrates included in this wastewater may affect the nitrate-nitrogen (N) in the groundwater. As stated in the above referenced report by Nolte Associates, the wastewater, from corn peeling, steeping, and cooking operations, drains to an approximate 404,000-gallon detention pond. It is our understanding that the wastewater contains small amounts of starch, citric acid, and lime. — The current groundwater flow direction on the site is generally towards the west. Two groundwater monitoring wells are located downgradient of the wastewater ponds and two monitoring wells are located upgradient of the wastewater ponds. To date nitrate as N has only been detected in one downgradient monitoring well (MW-3) with concentrations ranging from 0.5 mg/I to 1.5 mg/I:, The nitrate as N concentrations upgradient of the ponds ranges from 2 9 Tng/f to 7.8 mg/I. The MCL for nitrate as N is 10 mg/I. The shallow groundwater near the ponds does not appear to be affected by nitrate at this time. LIMITATIONS Kleinfelder has prepared this report in accordance with the generally accepted standards of care that exist in San Joaquin County at the time of writing. It should be recognized that definition and evaluation of geologic and chemical subsurface conditions are difficult. Judgments leading to conclusions and recommendations are generally made with an incomplete knowledge of the subsurface and/or historic conditions applicable to the site. The conclusions of this report are based on the information provided regarding the existing and proposed development and on-site conditions as well as our field observations, percolation test results, and experience in the project area. It was assumed that the percolation test results are representative of 50890.E02/STO6R1062 Page 2 of 3 Q 2006 Kleinfelder, Inc October 3, 2006