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boring were prepared on each of the four proposed parcels. Each test boring was pre-saturated the day before perc testing, In addition to pre-saturation, the shallow test borings were scarified to open smeared soil surfaces within the hardpan stratum caused by the drilling process. There was no standing water in any of the test borings after the 24-hr pre-saturation period, except the shallow test borings on parcels 3 and 4. As indicated on the attached FIELD PERCOLATION TESTING REPORTS, the shallow perc rate for parcel 2 was the only shallow test to have acceptable percolation. All four deep perc tests passed with relatively rapid rates. These deep perc rates illustrate the larger porosity of the underlying sand and gravel strata. The perc test results are summarized below for each of the four proposed parcels: PERCOLATION TEST RESULTS PARCEL No SHALLOW t42")PERC RATE IN MIN/INCH PARCEL No DEEP(25')PERC RATE IN MINANCH Parcel 1 75 min/in (Failed) Parcel 1 42 min/in Parcel 2 21,4 min/in Parcel 2 6,$ min/in Parcel 3 0 min/in (Failed) Parcel 3 4.6 min/in Parcel 4 0 min/in (Failed) Parcel 4 12 min/in III. NITRATE LOADING STUDY RESULTS A. GROUNDWATER INFORMATION 1. GROUNDWATER GRADIENT, VELOCITY AND ANALYSES The static water level under the center of the project is located approximately 120 ft below grade according to the 1999 Lines ofEquol Depth Map published by the San Joaquin County Flood Control District. The 1999 Lines of Equal Elevation map illustrate the groundwater to be approximately -30 ft MSL. Additional data was obtained from the attached 2000 Groundwater Contour and Monitoring Well Location Map for the Harney Landfill. This report indicates the groundwater elevation to be approximately -20 ft MSL. The 1992 Lines of'Equal Elevation map illustrates the groundwater to be -40 ft MSL. Therefore, the static groundwater level appears to have risen 20 feet in the past nine years. Groundwater directional flow is in a south-southeasterly direction according to the Groundwater Contour map. From this map, it appears the gradient is to the south near Harney Lane, and then changes to a southeasterly direction at the south end of the Landfill. 4