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Section 2 Soil Suitability Soil Profile and Geologic Information Natural Resources Conservation Service (NRCS) data for the Project site include soil samples to approximately 60" bgs. Two (2) soil types were identified, Capay clay (118) and Stomar clay (252). Both soils were described as "Moderately well drained" and capacity of the most limiting layer to transmit water as "Moderately low to moderately high". Both soils were also described as "Nonsaline to very slightly saline". NRCS surveys stated slopes ranged from 0 to 2 percent. See Appendix B. Soil samples were taken at each of the three (3) percolation test sites and analyzed by an independent laboratory for texture. Soils were classified as either clay or clay loam, with % clay ranging from approximately 36% to 49%. The laboratory test results are provided in the attachments. The laboratory test report is provided in Appendix D. Percolation Testing Percolation testing was conducted by Keir & Wright between June 16 and June 3, 2022. Three (3) percolation tests were performed at different locations on the property, and tests were performed at three (3) depths in all locations (See Appendix A). A soil mantle pit of 10' depth was excavated using a backhoe at each test site. No standing water was observed. Percolation test procedures conformed to the San Joaquin County Environmental Health Department requirements, as discussed herein. 1. Test Preparation: Shelves were cut at 24 inches, 48 inches, and 60 inches. In each shelf, a 12" x 6" diameter hole was prepared and 2" of gravel was added to the bottom of each hole. Soil removed from the hole was examined and logged. Reference boards were installed level and above the test holes. The test holes were saturated approximately 24 hours prior to beginning the test. 2. Test Procedure: A four (4) hour test was performed for each hole. Water level measurements were taken every 30 minutes or shorter (if the water level was low) during this four-hour period. A San Joaquin County Environmental Health Department representative was present on-site to observe the last half hour of each test. Test Results: The completed percolation test form from field measurements is included in the appendix. Field data includes percolation rates for each of the holes tested. Only two (2) of the nine (9) test holes failed to fall within allowable standard design limits. Since the project is proposing to construct and operate a wastewater treatment process, no standard on-site wastewater system design parameters are recommended herein. See Appendix C for field data. Results of the percolation tests are summarized in the following table. 31 Page