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FFA. COPE OF WORK llowing sZhe�, arizes the purpose and scope of work of this investigation and septic system criteria: Testing ysical and chemical characteristics of the soil under the future filter bed area. • Testing of the underlying groundwater and domestic water supplied by the City of Manteca. • Provide septic system design criteria to: 1.) Mitigate existing nitrate impact underlying the project, 2.) Prevent future additional nitrate impact from unexpected nitrate release from the treatment system, 3.)Assess possible mounding effects from effluent percolation onto the shallow water table, 4.) Determine nitrate impact without treatment, and 5.) Monitoring criteria. • Delineate and describe the design of the primary disposal and 100%replacement areas. II. SOIL TESTING Testing of the physical and chemical characteristics of the soil were conducted on two samples retrieved from a drilled test boring down to 12 feet. This boring was drilled outside the proposed disposal area in a location near proposed Building "C" according to the plans drawn by Associated Engineering Group of Modesto. A. Soil Physical Test Results Soil physical testing consisted of percolation, infiltration and particle size analysis of retrieved subsurface samples. Unified Soil Classifications (USCS) are found on the Percolation Test Form and Particle Size Analysis was done by A&L Laboratories of Modesto. Laboratory (USDA) classifications reveal the underlying soil to consist of a sandy loam at the 24 inch depth and a loamy sand at the 8-foot depth. Both samples had a clay content of 12%. Considering that confined animal soil containment structures must contain at least 10%clay to meet State of California Regulations, the particle size test results indicate that sufficiently,minimal clay content exists within the soil profile for biological activity to occur and to deter saturated flow conditions. Biological activity is favorable for the destruction of bacteria and viruses. The attached Water Well Drillers Report(Well Log) of the on-site well drilled in 1976 illustrates the strata underlying the property. As noted, coarse sand exists from 4 to 16 feet below grade. There is a considerable clay stratum from 16 ft to 60 ft. From 60 ft to 68 ft is a thin water bearing stratum with another significant clay layer from 68 ft to 116 ft. The second physical tests to be conducted were percolation and infiltration tests in the location of the future filter bed. Percolation testing was done at 24 inches and 42 inches below existing grade and according to EHD Regulations. After the borings were drilled on September 8,two inches of pea gravel was placed in each boring, along with athree-inch O.D. PVC perforated pipe, and each four-inch diameter boring was completely filled with water four times. This ensured complete soil saturation. Pere testing commenced on September 9 and was conducted Page -2- ChWey CMMAing