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KLEINFELDER Historically, the original restaurant at the site was constructed in approximately 1957. This facility was destroyed by fire, and a new restaurant was constructed in 1985/1986. Much of the original leach line and septic tanks associated with the original restaurant were removed, except for a polishing pond constructed by Parrish& Sons in the 1970's. The new kitchen now has two lines that first discharge into two 1,600 gallon grease traps which are cleaned at least twice a year. These grease traps then discharge into three large septic tanks placed in series, each with double compartments. The septic tanks then discharge to the polishing pond and from there to leach lines and seepage pits. Presented on Plate A-1 are photographs of the some of the lines and pits east of the residence, restaurant, and kitchen facility. The main elements of the system are accessible and visible. We understand that your recollection is that inspectors were present during the installation of the system. We further understand that you still have copies of invoices submitted from a firm in Escalon showing the sizes of the components installed at that time. GROUNDWATER DEPTH According to Lines of Equal Depth to Groundwater depth maps maintained by the San Joaquin County Flood Control and Water Conservation District, the depth to groundwater at this location is typically between 70 to 80 feet. As discussed below, there is an existing well at Pollardville which was sampled for a soils suitability study completed by our firm for the Korean Ebenezer Presbyterian Church located adjacent to and south of the site. The well was not sounded at that time. A water sample obtained from this well was submitted to Sequoia Laboratories for analytical testing of nitrate as N. The result, as reported in this referenced study, indicated a concentration of 2.25 milligrams per liter (mg/1). This value is consistent with other testing by our firm in this area which has also indicated relatively low nitrate levels. These low values are most likely attributable to the depth to groundwater and the presence of predominately clay and "hardpan"soils in this area that restrict downward percolation. FIELD EXPLORATIONS AND TESTING The subsurface conditions at the site were explored on November 18, 2002, by drilling two percolation test holes to depths of 3 feet (required shallow test) and approximately 10 feet (the required deeper test). The borings were drilled using a Simco 2400 truck-mounted drill rig equipped with 6-inch O.D. solid-stem auger. The locations of the percolation tests were approximately 110 feet east of the residence and 60 feet south of the gravel access road and fence in the area depicted in the photograph on Plate A-1. The percolation test locations are presented as P-1 and P-2 on the attached County percolation test sheets. Based on our findings, the subsurface conditions consisted of dark brown silty clay and brown sandy and clayey silt to the depth of approximately 8 feet. Between the depths of 8 to approximately 10 feet, a brown very-silty fine sand was encountered. The percolation tests were performed on November 20, 2002, in accordance with accepted guidelines using clear potable water. The procedure calls for first placing about 2 inches of fine gravel at the bottom of the bore hole. The hole is then pre-soaked with water at least 24 hours prior to performing the test. From a fixed reference point, the drop in water level is measured in 20-0268-01/ST02R886 December 5,2002 0 2002 Kleinfelder,Inc. Page 2 of 5