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The percolation testing protocol found the soils under the proposed effluent disposal area at the 40 inch depth to contain a sandy loam that was compacted in preparation for the construction of the Distillation Area Facility. This issue is discussed in Section IIC and the Conclusions Section. II. SOIL SUITABILITY STUDY FINDINGS A. 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 agricultural production land, primarily wine grape vineyards and almond/walnut orchards. There are surrounding rural residential structures, all on OWTSs and domestic wells. Application for Liquid Waste/Water Well Permits found in the EHD data base pertaining to the subject property and project exclusively were provided in the original SSNL. The area designated for septic tank effluent disposal is level terrain, but has been elevated above surrounding original grade by soil importation. From the elevation of this area, terrain slopes downward to original grade approximately 20 ft to the west of the proposed filter bed. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The UC Davis Soil Web indicates the future effluent disposal area soils consist of Honcut sandy loam (#175), with 4% Chuloak, 4% Tinnin, 4% Delhi, and 3% Veritas soils. SSS§ 5.2, NLS§ 1.1, 1.2. The soil investigation began on April 19, 2022. A shallow percolation test boring was drilled in the proposed effluent disposal area. A soil sample was retrieved from the 36-40 inch depth for chemical and particle size analysis. As noted on the attached A&L Laboratory Soil Analysis Report in Appendix B, chemical analyses of the soil samples quantify several constituents that influence nitrate loading for this specific project. These constituents include the organic matter, clay content, pH, cation exchange capacity (CEC), sodium and magnesium concentrations, and the nitrate -nitrogen fractions of the soil. The organic matter in the soil is very low, which is common in San Joaquin Valley soils. The soil at the sampled depth possesses 8.8% clay content. It was observed in a backhoe test pit for the original SSNL that clay content decreases substantially. The pH is very acidic at 5.7. This will have a significant effect on nitrification, since it has been observed that nitrification dramatically slows below pH 6.8. The CEC indicates low calcium, high magnesium and medium sodium concentrations. The high magnesium content most assuredly has an effect on the 74.3% sand content at this depth by binding the sand particles, leading to a restriction of permeability. Page -2- Chesney Consu[tin-