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r�A water sample was obtained from a hose bibb next to the domestic well and tested for nitrate and the agrichemicals DBCP/EDB. The nitrate water sample was placed in a plastic bottle and the DBCP/EDB sample was placed in a VOA bottle with preservative. The samples were placed in a cooled ice chest and subsequently delivered to A&L Labs in Modesto under the attached Chain of Custody. A low nitrate concentration of 15 ppm was determined in the well water and DBCP/EDB was Below Detectable Levels (BDL), which is non-detect. The depth of the sampled domestic well is unknown. Considering the intensely farmed land upgradient to the subject property over the past 60 years, a higher nitrate concentration would be expected. This may be attributed to the high clay content surface and subsurface clay soils and the deep groundwater elevation. High nitrate impact to the shallower aquifers and significantly lower nitrate concentrations in the deeper aquifers is often observed throughout San Joaquin County. CONCLUSIONS The deep perc test results for Parcel 2 in the specific area of testing, show acceptable percolation for the management of septic effluent flows that can be expected at a depth representative of sumps or limited depth seepage pits at 126 inches or 10.5 feet. This favorable soil material may be due to natural soil deposition from Little Johns Creek. Leachlines would manage only a very small volume of effluent flows. Although there is no proposal to build on Parcel 2, if building will take place in any area other than the area tested, EHD will require a perc test be done in that specific location. The area perc tested on Parcel 2 is not in the flood plain; however, any building must be built substantially above the highest irrigation levels. Parcel 1 perc tests exhibited failing rates for both the shallow and deep perc borings. Consequently, if a second unit dwelling is ever proposed to be built on this Parcel, an engineered system would have to be designed to compensate for these failing rates. As referenced, there is no proposal to build on either Parcel 1 or 2. Any future repairs or replacement to the primary residence or existing farm labor mobile home must be engineered. With regard to the DBCP/EDB testing, an extremely high DBCP concentration was found in a domestic well one-half mile north of the property. The acreage surrounding this well had been planted in grapes for several years during the 1970s and 1980s. This must have contributed to the DBCP concentration. Since the groundwater directional flow is to the northwest, this vineyard was downgradient to the subject property and probably explains why DBCP was not detected in the Van Vuren's domestic well. Additionally, Little John's Creek may have acted as a"barrier"preventing top aquifer water from traveling southward towards the Van Vuren property. The EHD requires that there be sufficient distance for"treatment" of septic effluent before it encounters the groundwater table. This distance is normally regarded to be five feet for leachlines and 10 feet for seepage pits. Therefore, sufficient distance exists between the bottom of a maximum seepage pit depth of 25 feet and the current groundwater depth of 103 feet. Chesney Consulting