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Freaused r table is shallow at approximately 8.5 feet. There is no potential for future septic ace waters, provided that for any future systems, applicable distance requirements are ere is virtually no possibility of the surfacing of effluent from inundated conditions ding since the land surface slope would allow adequate drainage. water samples were obtained for analysis. A sample from the domestic well on Parcel 1 (Mrs. Ormonde's well at 15345 West Grant Line) is a shallow well of approximately 70 feet in depth. This well was tested for both nitrate and the agrichemical DBCP. Nitrate test results show a concentration of 31 ppm NO3. Since the Maximum Contaminant Level (MCL) for NO3 in drinking water is 45 ppm, the nitrate concentration in this well is under the MCL, but over the median (one-half)MCL concentration of 22.5 ppm NO3. The agrichemicals DBCP and EDB were below detection limits(BDL), which is equivalent to non-detect (ND). The second well tested was Mr. Pereira's well. This well is approximately 200 feet deep and was tested for nitrate comparison with the results of Mrs. Ormonde's shallow well. Test results reveal a lower nitrate concentration in the deeper well at 3 ppm NO3 versus 31 ppm NO3 for the shallow well. Nitrate impact to the shallower aquifers and significantly lower nitrate concentrations in the deeper aquifers is observed often throughout San Joaquin County. CONCLUSIONS The perc test result for Parcel "I" suggests average percolation of septic effluent is to be expected at the maximum and typical leachline depth of 42 inches. As stated by Mr. Pereira, there have been no problems with his septic system, or with Mrs. Ormonde's, which may be attributed to keeping a close watch on water usage and the fact that no children live in either residence. The shallow perc test depth also reveals sufficient distance for "treatment" of septic effluent before it encounters the groundwater table. This distance is normally regarded to be five feet. It was also evident from the perc test that percolative capacity decreases with soil saturation. The Environmental Health Department may require that a new structure built, or moved onto the subject properties(both Parcel "I" and/or the Designated Remainder) have a percolation test done in the exact location of the proposed leachfield area. If a new septic system is installed at some time in the future, consideration may be given to installing the leachlines high in elevation to take advantage of the indigenous clay soils. These soils may enhance the denitrification process and take advantage of evaporative capacity during favorable weather throughout the year. A new system must have a 50% standby replacement area incorporated into the design and all related septic system structures and a possible new domestic well must comply with the published "distance" requirements from property borders, roads, irrigation fields,etc. It is important to note that all septic systems have a lifespan. This lifespan is dependant on several factors and is therefore difficult to determine. Although repairs and additions were not Page -3- Chemn Consulting