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within the one-mile study area: Two on Alice Road and one on West Ripon Road. These applications for repairs to existing systems were for additional leachline drainage; however, one additional drainage was to serve a home addition. These septic system repairs/additions within the study area can be considered a relatively low number, and indicate the shallow soils are conducive for acceptable, long-term sewage effluent management. [31 SOIL PROFILE AND PERCOLATION TESTING The surface soil profile from 0 ft to 2 ft consists of a light brown very fine sandy silt (SM). Sand content increases with depth; however, so does the density. Soil at the bottom of the perc test boring is comparatively tight and dense. Percolation testing was conducted on Parcel 1 in the area of the existing septic system. Pere testing was not done on the Designated Remainder, in accordance with Environmental Health Department regulations. A Log of Boring for the percolation test holes accompanies the FIELD PERCOLATION TESTING REPORT and illustrates the subsurface soil characteristics to the test depth of 42 inches. The boring was drilled, scarified and pre-saturated the day before testing. Readings were taken over a one-hour test period since the soil possesses a sand structure with water seepin awaX in 30 minutes before test. Perc test results reveal a fairly rapid perc rate of 14 minutes per inch(min/in) and indicate there is obviously granularity to the shallow soil structure. A Well Driller's Log closest to the subject property that was on file at the Environmental Health Department shows underlying soil structures to be intervening strata of sand and clay. [4] LOCAL GROUNDWATER AND SURFACE WATER INFORMATION The 1998 Lines of Equal Depth Map published by the San Joaquin County Flood Control District indicates the depth to groundwater in this area to be approximately 13 feet below grade. The Lines of Equal Elevation Map indicates the groundwater elevation to be 28 ft above mean sea level. The project elevation is 40 feet above sea level; therefore, the equal depth and equal elevation maps place the water table around 12 to 13 feet. The previously referenced well log reveals the depth of first water to be 19 feet in 1978. Therefore, the wa a 7 to i t 23 ears. Groundwater directional flow appears to be in a westerly direction toward the San Joaquin River. It is unlikely that perched water table conditions exist at higher elevations than the static water table. There is no potential for future septic impact to surface waters, provided applicable It requirements are followed, and there is no surfacing of effluent from inundated conditions caused by over-irrigation. 2 Va&y Ag research