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NLS 2. .,3.1 SSS 2.9,�.:t!7 Since surrounding properties have been intensely farmed for several de otential\ -fate con � ftamination in the underlying groundwater is signific However, well water obtained directly from the aquifers underlying the property indicate edium 'nitrate imps . This relatively low concentration may be attributed to the denitrification po tia hin.the-11t`nderlying aquifers, as referenced. A potential rise in the water table elevation may be from the cropland surrounding the property to the east and to the south. Irrigation recharge can have a significant influence on the underlying and surrounding water table, although in this locale it is my opinion that the rise in the water table elevation would be minimal due to the sandy nature of the underlying soil at the water table depth. The critical issue regarding the groundwater elevation is: 1.) There must be sufficient distance between the soil/effluent interface and the highest anticipated depth to groundwater for sufficient treatment of effluent to occur,which is generally accepted to be five feet, and 2.) The water table cannot encroach upon the septic tanks, which may cause buoyancy. These two issues are inconsequential to this project. NS§ 2.3 .SSS§ 4.3,4.4,4.5. As referenced, there a two xisting wells on the-property; the sar�le omestic well and art irrigation well. There is no ectricity to the*j well d therefore, was not sampled: On-May 9, 2007, the domestic well sampled under theTollowing procedures: The domestic well had been running for three hours because it was pumping to irrigate the small ag production acreage. Consequently, aquifer water and not stagnant well water was sampled. Well water was sampled from a sampling port on top of the well casing. A one pint plastic bottle was used for the nitrate analysis and a 100 ml plastic bottle was used for the , bacteriological sample. Thes_twc sample containers were placed in a cooled ice chest after sampling, and then transported to A"Agricultural Laboratories in Modesto under the attached Chain of Custody. As referenced, the constituents tested were for nitrate and bacteriological (Total and Fecal Coliform), exclusively, in compliance with EHD's request and under the California Uniform Retail Food Facilities Law (CURFFL). The following table illustrates the test results: TABLE 4 UNDERLYING GROUNDWATER ANALYSIS FROM ON-SITE DOMESTIC WELL ANALYTE LEVEL FOUND MAXIMUM CONTAMINANT LEVEL(MCL) Nitrate4�1 mg/L 45 mg/L Bacteriological: \bsent Absent Total and Fecal Coliform fVV Calculation of Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculations on Page 12 are contingent upon the environmental factors required for nitrification to occur. These conditions include soil pore-space oxygen content, soil temperature,pH, electrical conductivity, organic matter, cation exchange capacity, and alkalinity. Alkalinity in wastewater effluent is derived from the domestic well water supply in addition to the introduction of wastes. 6 Chesney Consulting