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CONCLUSIONS AND RECOMMENDATIONS In summary, the soil conditions examined near the potential future septic drain field were found to be suitable for a standard septic system. Satisfactory soil percolation rates of 1.93 min/in (shallow) and 5.95 min/in (deep) were observed in the soil at the test location. The soil in the test location was found to be sandy silt, silty sand, and sand with silt. No septic construction is planned at this time. The depth of ground water based on recent aquifer levels is approximately 81 to 84 feet below ground surface. The ground-water flow is to the south-southeast in the area at a rate of approximately 11 to 13 feet per mile. Water samples were collected from the main well and fire suppression well on the Site as part of this investigation. Nitrate was detected in the samples at concentrations of 2.6 and 3.2 mg/L-N, respectively, well below the MCL of 10 mg/L-N. DBCP was detected in the samples at concentrations of 0.63 and 0.81 A,g/L, respectively, significantly above the MCL of 0.2 [Ag/L. The well water should not be consumed until it can be brought to below the MCL. Delta Packing is currently working on a plan to mitigate DBCP through the use of an ozone system. Additionally, the facility currently supplies bottled water for worker consumption at watering stations. Based on the methods and assumptions described, the nitrate loading calculation indicates that the use of on-site septic tanks and drain field systems on the Site has the potential to cause a buildup of nitrate in the aquifer up to 2.3 mg/L-N, well below the MCL of 10 mg/L-N. Septic system construction utilizing leach lines and seepage pits should follow the San Joaquin County On-Site Wastewater Treatment Systems Standards (2017) where applicable. Based on the results of the nitrate loading analysis, no nitrate mitigation is recommended. LOGE 20-33 Page 16