SR0080386 SSNL - Laserfiche WebLink

Home Browse Search

Table 2. Percolation Test Summary Test No., Percolation Test Percolation Rate Test Duration Comments Date Tested Depth (ft.) (minutes/inch) (see notes) P1, 3/13/2019 3.17 2.98 1 hr. Satisfactory pert. rate Shallow Test Note: A satisfactory percolation rate for a "shallow" test is greater than 1 but less than or equal to 60 minutes per inch. 1 Per San Joaquin County Environmental Health Department, a rate between 1.0 and 5.0 min/in requires a 20' separation between the bottom of dispersal system and ground water, or mitigation by system design or enhancement. Discussion of Percolation Test Results The soils within the proposed sewage disposal area of the Site have demonstrated a satisfactory percolation rate for the use of a standard septic system in accordance with the requirements of the San Joaquin County Environmental Health Department. Because of the percolation rate between 1.0 and 5.0 encountered in the test hole, the San Joaquin County Environmental Health Department will require a 20-foot separation from the bottom of the dispersal system to ground water (see Table 2). Ground water is anticipated to be encountered approximately 45 to 58 feet below ground surface at the Site; consequently, no modifications to standard septic systems should be required. If the 1983 high ground-water level of 30 feet below ground surface is to be considered, sumps no deeper than 10 feet should be utilized rather than 25-foot deep seepage pits; this option should be discussed with the San Joaquin County Environmental Health Department. The existing septic system utilizes eight-foot-deep sumps. Discussion of Septic System Sizing Septic system construction utilizinLlleach lines and seepage pits or sumps should follow the San Joaquin County On-Site Wastewater Treatment Systems Standards (2017) where applicable. It is anticipated that the new office building will connect to the existing septic system. LOGE 1912 Page 9