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C. PERCOLATION TEST RESULTS SSS§ 6.2. As referenced,to assess the permeability of the proposed leachfield soils,percolation test borings were completed as noted. Four perc tests were conducted within the leachfield area due to its large size. Test locations are depicted on the project Site Plan produced by Lawrence Engineering Group. SSS§ 6.3. After drilling, the sidewalls of the four borings were scored with a pry-bar to open potentially smeared soil surfaces and the cuttings removed. Two inches of pea gravel was placed at the bottom and a three-inch perforated PVC pipe was inserted in each test boring. After these procedures,the borings were pre-saturated with 12 inches of water approximately 24 hrs prior to the start of testing. SSS§ 6.4,6.5. On June 30 and July 1, 2020,percolation testing commenced at 0700 hrs. No standing water was observed in any of the borings after the 24-hr soak period. Consequently, EHD Perc Test Procedure#2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation. A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil per day, along with the averages,are illustrated below: TABLE 2 PERCOLATION TEST RESULTS WITH CORRESPONDIN� G APPLICATION RATES IN GALLONS/FT'/DAY NEC40 PERC TEST 10.0 min/inch / 0.800 gallons/ft/day Northeast Corner 40"Deep Pere Test NWC40 PERC TEST 13.9 min/inch / 0.743 gallons/ft/day Northwest Corner 40"Deep Pere Test SEC40 PERC TEST 11.4 min/inch / 0.786 gallons/ftZ/day Southeast Corner 40"Deep Pere Test SWC40 PERC TEST 11.4 min/inch / 0.786 gallons/ft/day Southwest Corner 40"Deep Pere Test AVERAGES 1 11.7 min/inch / 0.779 gallons/ft/day Application Rates adapted from Waste Quality Control for Saing Design,Operation and Maintenance of On-site Wastewater Treatment Systems,based on the Pert Rate. D. GROUNDWATER INFORMATION NLS§2.1, SSS§ 4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The 2007 Lines of Equal Depth Map indicates the depth to water at approximately 40 ft. The Fall 2016 Lines of Equal Depth Map illustrate approximately 70 ft depth to groundwater,thus revealing a significant drop in water table elevation due to excessive pumping and limited recharge during serious drought periods. From the Lines of Equal Elevation Maps, groundwater directional flow appears to be in a north-northeasterly direction. Page -4- Chesney Consulting