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C) 1 + The Banta area has always had a significantly higher number of repair permits due to the clayey soil and shallow groundwater, and may also be due to inadequate systems originally installed, in addition to the age of the systems. The project site has level terrain; conse uentl there will be no need to incorporate design p J � q Y� rP considerations for slopes within a disposal area. Under EHD requirements and regulations, a mound system for effluent disposal can be required in this locale due to the clayey soils and more particularly, the high groundwater table. Mound systems are sensitive to sloping, and changes in design must be taken into consideration when natural ground sloping is present. However, based upon the findings of these Studies, particularly with respect to depth to groundwater and the theoretical rise in the water table, a mound system may not be required. A filter bed system and disposal parameters will be discussed in a design report for any future project on this property. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture - Soil Conservation Service (USDA-SCS) indicates the property soils are on the edge between Stomar clay loam (#252) and Willows clay(#274). The Soil Survey of San Joaquin County states that permeability is slow and very slow in these two soils, although this was not observed in the percolation tests conducted. SSS§ 5.2.The surface and subsurface soil investigation and testing began on May 16, 2007 with hand drilling a 24-inch and 40-inch percolation test boring in the extreme north corner of the property. This test location was chosen for two reasons: First, a required distance of 100 ft had to be maintained between the test locations and the on-site well, and the two wells on adjoining properties. Secondly, it is probable that a wastewater disposal area for any future commercial development of the property would take place in the"back"of the property, near this north corner. The test locations are denoted on the San Joaquin County Site maps found in Appendix A. Soil cutting samples from the bottom of these two borings were retrieved for physical and chemical analysis. On May 24, 2007, a backhoe became available from Santos Backhoe Service to sample soil at deeper depths. Samples from 72 inches and 92 inches in depth were retrieved. At the 17-inch depth, very moist soil conditions were encountered which was representative of the capillary fringe. At e 92- inch depth, saturated soils conditions were encountered and groundw er seeped into the test�it. After one hour, the depth to standing water within the test pit was17.2 feet below the ground sur ace, then a water table sample was retrieved with a stainless steel bailer--T e test pit was then subsequently closed-in. NLS§ 1.1, 1.2. As the noted on the A&L Laboratory Soil Analysis Reports, chemical analyses of the four soil samples quantify several constituents that influence nitrate loading from this project. The important parameters for nitrate loading assessment are the organic matter, pH, cation exchange capacity(CEC), clay content percentage, along with nitrate-nitrogen content of the soil. As noted, the organic matter in the surface soils is actually lower than in the deeper soil samples. The nitrate-nitrogen concentrations are again low at 4 ppm and 3 ppm at the 24" and 40" depths,but increases to 6 ppm at both the 72" and 92" depths. t 3 Chesney Consulting