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SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. The Google Aerial photo illustrates the subject property. Land use to the immediate north, south, east and west is open land, the town of French Camp, sparse rural residential, and commercial/industrial properties. The surrounding rural residential units are all on onsite wastewater treatment systems and domestic wells. SSS§ 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 6.8. Permit applications within the one-half mile radius study area from the property were reviewed for repairs/replacements/additions to existing septic systems. Three permits primarily for repair of leachlines were found. This can be considered a typical number of permits within a study area, particularly since rural residential units are sparse. Considering the increasing permeability with increasing depth, OWTS in this locale should have comparatively long life spans. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The UC Davis Soil Web indicates the future effluent disposal area soils consist of Veritas fine sandy loam (#266), with 4% Tinnin soils. SSS§ 5.2, NLS§ 1.1, 1.2. The surface and subsurface soil investigation began on December 29, 2021. A Mobile Drill Rig was used to drill down to 20 ft below grade, one ft immediately adjacent to the east end of the sump effluent disposal structure. Soil samples were retrieved that unquestionably are being influenced by septic effluent. The sump structure is 48 ft L x 15 ft W x 7.5 ft D. Soil samples were obtained from the 5 ft, 10 ft, 15 ft and 20 ft depths using a split-spoon sampler. Consequently, precise soil sample depths were sampled. The attached A&L Laboratory Soil Analysis Report in Appendix B illustrates the chemical analyses of the soil samples quantifying several constituents that influence nitrate loading for this project. The primary parameters for nitrate loading assessment are the organic matter, clay content, pH, cation exchange capacity (CEC), Total Kjeldahl Nitrogen (TKN), and the nitrate-nitrogen fractions of the soil. The organic matter in the samples is low, which is typical for San Joaquin Valley soils. The 5ft depth possesses 6% clay content, increases substantially to 22% and 46% in the 10 ft and 15 ft depths, respectively, and then decreases to 20% at the 20 ft depth. The pH of the soil is alkaline and may be causing a decrease in Nitrobactor activity, thus inhibiting the second step of the nitrification process. The TKN concentration increases 175% from the 5 ft to the 15 ft depth, but decreases 44% from the 15 ft to 20 ft depths. The nitrate-nitrogen concentrations reveal a concentration of 4 ppm at the 5 ft depth, and then decreasing to 1 ppm at the remaining three sampled depths; a 75% reduction. This 75% decrease indicates the denitrification potential that will be used in the nitrate loading calculations and can be attributed to sufficient organic matter, increasing clay content, and saturated subsurface soil conditions. NLS§ 3.3, SSS§ 5.3, 5.4. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil samples: Page -2- Chesney Consulting