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[3] SOIL PROFILE AND PERCOLATION TESTING The perc test boring was hand-drilled; therefore, the surface and subsurface soil characteristics were easily identified. Surface soil consists of a compacted fine sandy silt. Compaction has occurred from machinery between the tree rows. Below approximately 20 inches, the soil becomes much less dense and tight, and continues to become less compacted with depth. The surface and subsurface soils have been classified under the Unified Soil Classification System (USCS). Classifications are illustrated on the Percolation Field Test Form and are as follows: ML=silt and SM=sandy silt. One perc test boring was hand-drilled on proposed Parcel 1, in the center of the proposed leachfield. This test location was determined from the surveyor's markers, and a tape measure was used to find the exact center ' osal field. The boring was drilled to a depth of 42 inc es. a oring was not scarified due to the sandy characteristics of the soil. After drilling, two inches of gravel was placed in the four-inch diameter boring and pre-saturated on October 9, 2003, the day before testing. Presaturation consisted of completely filling the test boring with water. On October 10, the test boring had no standing water. The perc test was started under Test Procedure #2 and readings taken over a four-hour test period to ensure that the soil was completely saturated during the test. Although the entire head water seeped away in the first 30- minute segment, the test could have been run under Test Procedure 3#. The four-hour test revealed that the perc rate slowed in response to increased soil saturation. However, perc test results still show a rapid perc rate of 7.9 minutes per inch(min/in)at the end of the four-hour test and suggest excellent percolative capacity, even under saturated conditions. [4] LOCAL GROUNDWATER AND SURFACE WATER INFORMATION The 2000 Lines of Equal Depth Map published by the San Joaquin County Flood Control District illustrate the depth to groundwater in this area to be between the 10 and 20 foot lines of equal depth, so about 15 feet below grade. Lines of Equal Elevation Map shows the groundwater elevation to be approximately 38 feet mean sea level. The project elevation is approximately 55 feet above sea level; therefore,the groundwater equal elevation map correlate with the water table depth. From the equal lines map,the groundwater directional flow is in a westerly direction, toward the San Joaquin River. It is highly unlikely that perched water table conditions exist at higher elevations than the static groundwater table. There is no potential for future septic impact to surface waters. As referenced above, the cherry trees are under micro-sprinkler irrigation, so no possibility exists of inundated conditions caused by flood irrigation. 2 Chemey Consulting