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UEC Document No.: R3579811 December 7, 1998 Soil Percolation test hole #3 maintained good integrity throughout the 4 hour time period of the soil percolation test. During the test, drops in water level ranged from 3.75" in a 30 minute interval to 0.5" in a 30 minute interval. The 0.5" drop in water level was observed during the final test interval; the following calculated percolation rates are based upon the final test period. The resultant calculated soil percolation rates for hole#3 are .0167 inches of water per minute or 59.9 minutes per inch of water. Consequently, the area located immediately north of the Calva Products structure and west of the existing septic system percolates adequately. 3.0 NITRATE LOADING ANALYSIS An analytical assessment of the potential impact to groundwater from nitrates contained within the septic system waste water has been performed by the UEC staff; the basis of the assessment is the research work performed by Norman N. Hantzche of the Questa Engineering Corporation and E. John Finnemore of the Department of Civil Engineering at Santa Clara Universi . %us oil samples were collected as part of this assessment; the assumptions made and the n ric al in performing our calculations are meant to be representative of the current site an t 113 st usage conditions. 3.1 Site Hydrogeology According to the SJC Flood Control and Water Conservation District "Lines of Equal Depth To Groundwater" map dated Spring 1997, the approximate depth to groundwater beneath the site is 50 feet; heavy rainfall between the Spring of 1997 and the Spring of 1998 may be expected to have raised the groundwater level no more than 10%,, or to a depth of 45 feet below grade. The groundwater flow direction tends to be to the east-northeast in the immediate vicinity of the subject site. 3.2 Known Wor Suspected Nitrate Sources A primary source of nitrate groundwater contamination tends to be from dairy farms and other farming operations where large quantities of livestock reside. No such farming operations exist on or adjacent to the subject site. Additionally, certain food processing plants have the capacity to discharge waters which contain relatively high levels of nitrogen which is eventually transformed into nitrates. Victor Foods, existing to the east of the subject site and east of State Highway Route 99, may be a source of elevated nitrates; Victor foods appears to be down gradient of the subject site and could therefore be expected to have minimal impact on the groundwater beneath the subject site. However, groundwater gradients have a tendency to fluctuate, especially in agricultural areas; as a result, the impact of the Victor Foods site upon 4