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Topography of the site is flat with very little change in elevation; consequently, no slope compensating factors will have to be incorporated into the design of the septic systems. The north property line contains the Angel Lateral for the Oakdale Irrigation District (O.I.D.). There are various easements at the north and south ends of the subject parcels. The subject property is located 8 miles northwest of Oakdale, and 1 mile west of the town of Valley Home. The study area consists of predominately agricultural production land, primarily rice land, dairies and pasture. Surrounding structures consist of very low density single family housing, dairy farms and ranchettes. Current zoning of the property is AG-40. A review of Application Permits on file with the San Joaquin County Environmental Health Department indicates there have been six Applications for Repairs/Additions in the one mile diameter study area. These applications for system modifications to existing systems were for additional drainage(leachlines), sumps and seepage pits. This can be considered an upper-medium number of Applications considering the low density housing in the area and indicates the shallow soil is not conducive for acceptable septic effluent management. The closest Well Driller's Logs that were on file at the Environmental Health Department shows varied soil strata of sand and clay down to 175 feet in depth. [3] SOIL PROFILE AND PERCOLATION TESTING Backhoe trench pump-in percolation tests were conducted on each of the four Parcels. No perc test was done on the Designated Remainder in accordance with San Joaquin County Department of Environmental Health Department regulations. All percolation test procedures were conducted according to Health Department regulations. Perc test locations are denoted on the attached PARCEL MAP. The Field Test Data Sheets with the percolation test results can also be found in the Appendix. The percolation test pits were composed of lean clay down to severe hardpan. The hardpan layer is composed of cemented silts and is found at various elevations and various thicknesses. It was nonexistent at the perc test location of Parcel 2. Due to the fact that at this point in time it is unknown where future septic systems will be placed, it must be assumed that hardpan conditions will be prevalent throughout each of the four Parcels. Generally, below the hardpan layer exists a very fine sandy silt and silt strata which becomes sandier with depth. However, each of the parcels exhibited completely different soil strata and again,it can be assumed that extreme soil variability will be encountered on each of the four parcels during septic system emplacement. The water drop and the calculated perc rate for the last half-hour of the four-hour test period for each of the four parcels is as follows: Parcel 1: 4.0 in. water drop= 7.5 min/in Parcel 2: 0.72 in. water drop=42 min/in Malley?Ig?research