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Trans Sohal Logistics—Soil Suitability Section Page 6 of 13 Our Project Number: LGS140011 October 8,2014 performed for soil characterization to aid in the design of a proposed on-site septic field to be performed at a later date. 1.6.3 Boring Preparation and Presaturation The two soil borings were advanced on the subject property with a Simco Drilling Rig on September 16, 2014. Approximately two (2) inches of "pea gravel" were placed in the bottom of the open soil borings, then 1.5-inch diameter PVC pipes with perforations on the bottom were installed on top of the gravel in each boring. "Pea gravel" was then used to backfill in the ✓, annular space. Presaturation of the percolation test holes occurred approximately 24 hours prior to the day of testing (September 17, 2014). The depth of water used to pre-soak was 12 inches and 6 inches above the bottom of the borings for the shallow and deep tests, respectively. 1.6.4 Condition of Borings After Presaturation After the 24-hour soak period, the presaturated holes were found to be intact and dry on the 6'.a day of testing (September 17, 2014). 1.6.5 Percolation Test Procedure Percolation tests were conducted for the two borings on September 17, 2014 in accordance with the requirements of the San Joaquin County EHD. Each percolation test had a duration of four hours. The last half an hour of each test was observed by Michael Escotto, Registered Environmental Health Specialist (REHS), EHD. Measurement of the water level during the percolation tests was from a fixed reference point on the PVC casing using an electric well sounder with a depth accuracy of 1/100th foot. All tabulated values on the field data sheet (Appendix C) are in decimal feet. After water drop was observed, the holes were checked for refill. The holes were refilled as necessary to maintain approximately 0.5 feet (6 inches) of water above the bottom level of the percolation test holes. The readings were taken every 30 minutes for a period of four (4) hours. 1.6.6 Percolation Test Forms and Results The completed percolation test form with Michael Escotto's REHS verification signature is included in Appendix C of this report. A shallow percolation test is defined by the EHD as being between 36 and 42 inches in depth; a satisfactory percolation rate for a shallow test is less than or equal to 60 minutes per inch drop. A deep percolation test is defined as being between 3.5 and 25 feet in depth; a satisfactory percolation rate for a deep test is 30 min/in or less. One percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field of a parcel to utilize a standard septic system. Details of the percolation tests are summarized in the table below. ©2014 Neil O.Anderson&Associates,Inc. A Terracon Company