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The test results indicate a perc rate after complete soil saturation of 83.3 min/in for the 24" boring and 50.0 min/in for the 36" test boring. The 36" test boring is the official EHD test. A perc rate of 60 min/inch or faster is considered passing and rates slower than this require an engineered system. A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil per day are illustrated in Table 2 below: TABLE 2 PERCOLATION TEST RESULTS FOR BUILDING E&E WITH CORRESPONDING SOIL TYPE, PERCOLATION RATE AND APPLICATION RATE IN GALLONS / FV / DAY 24 INCH DEEP PERC TEST BORING 83.3 min/inch / 0.123 gallons/ft-/day SILTY CLAY LOAM (CL -ML) 36 INCH DEEP PERC TEST BORING- OFFICIAL TEST 50.0 min/inch / 0.311 gallons/ft'/day SILTY CLAY LOAM CL -ML Application Rates adapted from Table 3 of the OWTS Policy of the S WRCB and is correlated with the Perc Rate obtained. D. GROUNDWATER INFORMATION NLS§ 2.1, SSS§ 4.1. There has been groundwater monitoring over the entire North Tracy/Holly Commerce Center that has determined the water table to be relatively shallow in this locale. Siegfried has completed an entire topographical survey of the project, which has been correlated with the measured water table elevations. NLS§ 2.2, 3.1, SSS§ 2.1, 4.2. As referenced, past land use has significantly affected the underlying soils and groundwater. In addition, since the surrounding properties have been farmed for a number of decades, this has also contributed to a potential increase of nitrate concentration within the upper groundwater aquifers. A water table sample was retrieved from a boring adjacent to the perc test borings. Test results reveal a nitrate as nitrate concentration of 85.1 ppm, which is nearly 2x the drinking water MCL for nitrate. The concentration translates to 51.9 lbs of nitrogen/ac-ft of groundwater and will be discussed further in the Conclusions Section of this report. Total Alkalinity is 400 mg/L and discussed below. The electrical conductivity is a very high 41.1 mmhos/cm and the pH is almost neutral. The Total Kjeldahl Nitrogen (TKN) is the measurement of the ammonium and organic nitrogen fractions, and was also found to be a high concentration. Most of this concentration should be in the ammonium fraction. Page -4- Chesney Consulting