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Test results reveal the water contains 107 ppm nitrate(as NO,),which is 2.38 times the Maximum Contaminant Level (MCL) for drinking water at 45 ppm. The DBCP concentration was found to be 3.2 gg/L, which is 16 times the MCL for DBCP at 0.2 gg/L (ppb). The agrichemica was oun to be non-detect (ND). Regarding surface water, the subject property is in the A-O Flood Zone due to the adjacent Little Johns Creek. The prior history of the property included two large irrigation reservoirs, as denoted on the USDA Soil Map, which were removed when the almond trees were planted. If the property is ever developed in the future, on-site stormwater management will have to be incorporated into the development plans for each Parcel. This should pose no problem given the size of each individual Parcel. CONCLUSIONS The perc test results for proposed Parcels 1, 2, 3, 4, 5 and 6 show acceptable percolation for the management of septic effluent flows either from leachlines or from seepage pits, and/or possibly sumps. The proposed Parcels are obviously large areas (61.8 acres each). A structure and accompanying improvements such as pools, landscaping, driveways, a potential second unit dwelling, etc. would take up a small percentage of the total parcel area. It appears from our testing program, that favorable soil with acceptable percolative capacity exists north of the dirt road(access easement) that traverses east-west through the middle of the property. If structures are proposed for any of the Parcels in the future, they should be built north of this access easement. If structures are proposed in any other location,primarily south of the access easement, the EHD may require percolation testing in the anticipated disposal field location. 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 seepage pit (25 feet) and the current groundwater depth of approximately 93 feet. The attached Well Logs indicate the standing water level to be 125 feet in 1984 and 104 feet in 1973; therefore,the groundwater level has risen in the past three decades. Each of the deep perc test borings were terminated at the referenced depths when a sand strata was encountered, instead of drilling to the maximum depth of 25 feet(except for Parcels 1 and 2). By terminating the borings at these depths,the effluent managed by future deep septic system structures on the property can be installed with the greatest distance possible from the underlying groundwater table. Since the sand strata were encountered at relatively shallow depths for Parcels 3, 4 , 5 and 6, approval may_be sought from EHD to install sumps with an extend-a-hod,in lieu of seepage pits. Infiltrator.Chambers®should be_cons idered and are recommended for any-new septic system proposed for the six Parcels to keep the soil/effluent interface as high in elevation as possible. This is to take advantage of the evaporative and evapotranspiration capacity during favorable weather conditions throughout the year. In addition, the full lineal feet of leachline requirement must be used when chambers are installed. This theoretically provides for additional drainage. Other than this deviation from conventional leachlines, there is no need for engineered septic systems. Page -4- Chesney Consulting