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✓ On March 5, 1000 hours, percolation testing commenced for the two borings. There was no standing water in the test borings after the soak period. The initial volume of water did not seep away in the first 30 minutes at the start of the percolation tests for the test borings. Consequently,Percolation Test Procedure#2 was used in which perc readings for the two borings were taken over a four-hour test period to ensure maximum soil saturation under"worst- case scenario" conditions. The two perc tests exhibited identical and mediocre percolation rates for both parcels. The last half hour of the tests was witnessed by Michael Escotto of the San Joaquin County Environmental Health Department. The following chart summarizes and illustrates the parcel number,proposed acreage and perc test results: PROPOSED PARCEL PROPOSED ACREAGE PE ST RESULTS Parcel 1 7.89 Acres 35.7 min/in @-4d inches depth Parcel 2 5.00 Acres 5.7 min/in @ inches depth LOCAL GROUNDWATER AND SURFACE WATER INFORMATION The 1999 Lines of Equal Elevation Map published by the San Joaquin County Flood Control illustrates the groundwater elevation and the directional flow. It appears, and is generally accepted, that the groundwater is flowing in a north-northwest direction toward the San Joaquin River; however, at the intersection of Small Road and French Camp Road, the groundwater flow appears to be in a northeast direction. The 1999 Lines of Equal Depth Map illustrate the groundwater depth to be 27 feet below ground surface. A Well Driller's Log for a domestic well on South Small Road, directly to the southwest was available to illustrate the underlying soil lithology. Interestingly, the well log shows clay from 5 feet to 57 feet below grade. Consequently,perched water table conditions probably do not exist at higher elevations than the existing water table. From the 57400t depth on down to the well depth of 160 feet,there are intervening strata of sand and clay. Considering that the soil was saturated from this winter's heavy rainfall and pre-saturation, there is an extremely remote possibility of the surfacing of effluent from inundated conditions caused by flooding. The porosity of the subsurface soils as evidenced from the percolation test results should allow for adequate drainage. The subject property is not subject to the 100-year flood. It will be a reglement of EHD to install a 200-foot snout seal due to the proximity of the property to-the-Sharpe Army Depot. A water sample was obtained from a hose bibb 75 f .t w of h . domestic well and tested for nitrate and the agrichemicals DBCP/EDB. The nitrate water sample was placed in a plastic bottle and the DBCP/EDB sample was placed in a VOA with preservative. Both samples were placed in a cooled ice chest and subsequently delivered to A&L Labs in Modesto under the attached Chain of Custody. A low nitrate concentration of 11 ppm was determined in the well water and DBCP/EDB was non-detect. The depth of the sampled domestic well is unknown. Page -3- Chesney Consulting