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The percolation exhibited an excellent final rate of 7:4 min/in. There was an approximate 33% decline in the perc rate over the four hour period. The last half hour of the test was witnessed by Justin Hess of the San Joaquin County Environmental Health Department. In addition to the conventional perc tests described above, hydraulic conductivity data of shallow soils from zero to 24 inches in depth has been conducted in similar soils in.a parcel approximately one-quarter mile to the east of the subject property. Hydraulic.conductivity testing was not, conducted in the area of percolation testing since the soils had been plowed in the cherry orchard. After four hours of testing in the same type soil as the subject property, it was determined that the shallow soils absorb 1,200 cc/hr. This is equivalent to 0.00528 gal/min or 7.6 gallons/day. Since the internal area of the 24-inch deep x 4.5 inch dia. boring was 355 in' or 2.5 ft', the application rate for the surface soils is theoretically 3.0 gallons/ft'/day. In comparison, the percolation test run in conjunction with the above-referenced hydraulic conductivity test exhibited a perc rate of 10.0 min/in. The percolation test for the subject property and the hydraulic conductivity test performed on a nearby property two years ago are summarized in Table 3: TABLE 3 ° } RESULTS17. t SHALLOW PERC TEST PERC RATE IN ASSUMED HYDRAULIC GALLONS/SQ MIN/INCH -CONDUCTIVITY FROM FTIDAY A NEARBY TEST Conducted in the Anticipated 7.4 min/in Shallow Soils(24 in) 3.0 gals/W/day Leachfield of a Second Unit Dwelling Homesite: Shallow Soils(38 in.) III. NITRATE LOADING STUDY FINDINGS A. GROUNDWATER INFORMATION The static water level in the DeAngelis domestic well was measured at 52 feet on 9-13-01 and 50 feet on 10-28-02, as depicted on the two attached Well/Pump Permits. The Lines of Equal Depth Map and the Lines of Equal Elevation Map published by the San Joaquin County Flood Control District do not illustrate the groundwater depth and elevation for the Tracy area. However, the 1992 Lines of Equal Elevation map illustrates the groundwater flow to be in a northeasterly direction. This groundwater directional flow is confirmed by the contaminant plume originating from the Tracy Defense Depot that has been under remediation for several years. Page-6- Chesney Consulting