SU0003975 SSNL - Laserfiche WebLink

Home Browse Search

..� kn KLEINFELDER ENVIRONMENTAL HEALTH DEPARTMENT PERMIT REVIEW A study was conducted on adjacent properties to evaluate the performance of existing septic systems. On April 25, 2003, an employee of the Environmental Health Department (EHD) pulled the relevant permits on file to conduct this evaluation. Only 2 septic permits were on file, both for adjacent properties. The first Permit, No. 74-386, dated May 10, 1974, was for 11708 East Tokay Colony Road. This permit is for an addition of one 80-foot leach line and an addition of one 33-inch diameter by 25-foot deep seepage pit. The second Permit, No. 71-314, dated April 12, 1971, is for the installation of three 75-foot leach lines and two 33-inch diameter by 25-foot deep seepage pits. Both of the permits were for additions/installations. GROUNDWATER DEPTH During the time of our investigation, groundwater was not encountered. Lines of Equal Depth to Groundwater contour maps published in groundwater reports by the San Joaquin County Flood Control and Water Conservation District show groundwater levels in the project area ranging from about 90 to 115 feet below ground surface from Spring 1981 to Spring 1999. FIELD EXPLORATIONS AND TESTING The subsurface conditions at the site were explored on January 20, 2003, by drilling four percolation borings to depths between approximately 6.5 and 7.5 feet below existing grade. The borings were drilled using a Simco 2400 crawler-mounted drill rig equipped with 6-inch diameter solid-stem auger. The locations of the percolation tests are given in the table below. The approximate percolation test locations are presented on the attached plate. Parcel Number Location 1 280' east and 420'north of southwest property corner 2 570' east and 300'north of southwest property corner 3 260' east and 785'north of southwest property corner 4 540' east and 730'north of southwest property corner Based on our findings, the subsurface soils encountered consisted of surficial clay underlain by interbedded layers of clayey and sandy silts and silty sands to the maximum depths explored. The percolation tests were performed on April 21, 2003, in accordance with accepted guidelines using clear potable water. The procedure calls for first placing about 2 inches of fine gravel at the bottom of the borehole. The hole is then pre-soaked with water at least 24 hours prior t performing the test. The 6.5 to 7.5-foot deep tests were performed by adding about 1 to 2.5 feet of water above the gravel in the hole. From a fixed reference point, the drop in water level is measured in approximately 30-minute intervals for four hours, refilling as necessary to maintain the prescribed amount of water over the gravel. Under the observation of a sanitarian from the San Joaquin County, Environmental Health Department (SJC/EHD), the last 30-minute reading 25208.G01/ST03R716 May 5,2003 ©2003 Kleinfelder,Inc. Page 2 of 3