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TABLE 1 <br />PERCOLATION TEST RESULTS AND RELATED DATA <br />SEPTIC SYSTEM <br />PERC TEST <br />POST -SOAK PERIOD <br />PERC TEST <br />ACCEPTANCE RATE <br />STRUCTURE TO BE <br />DEPTH <br />STATUS <br />RESULTS <br />INSTALLED <br />Proposed Four <br />40 INCHES <br />No Standing Water <br />25.0 min/in <br />0.589 <br />Bedroom House: <br />(3.3 FT) <br />in Test Boring After 24 hr <br />gals/ft`/day <br />1600 Gallon Septic <br />Pre -Soak <br />Tank <br />320 Lineal Ft of <br />Leachline (LFLL) <br />CONCLUSIONS <br />The shallow depth percolation test results indicate a conventional OWTS with leachlines can be installed <br />under EHD permit and requirements. Eventually, however, due to biomat buildup and the quasi -sealing of <br />the leachline trenches, this may impede percolation to the extent that the 100% replacement area must be <br />activated. Ample area exists on "the subject property for the 100% replacement area since it is three acres. <br />The proposed OWTS should have a comparatively long lifespan. <br />From the acceptance rate obtained, the OWTS to be installed can manage: <br />0.589 gals/ft'/day x 1,280 ftZ (infiltration area of 320 LFLL) = 754 gpd. Residences of a four-bedroom <br />house theoretically produce between 280 and 560 gpd of wastewater. <br />Based upon Table 1. 10.2 of the SJC OWTS Standards - Minimum Soil Depth from the Bottom of <br />Dispersal Systems to Groundwater, as determined from the perc rate of 25 min/in, there is to be an eight ft <br />minimum soil depth. In Spring 1999, the depth to groundwater was measured at 28 ft bgs. This can be <br />considered the highest depth to groundwater. In the Spring of 2017; the depth to groundwater was <br />measured at approximately 45 ft bgs. This drop in water table depth is due to drought and over -pumping. <br />Therefore, there will be currently more than 40 ft separation distance after OWTS installation. <br />If there should be any questions regarding this report, please contact the undersigned. <br />Respectfully submitted, <br />CHESNEY CONSULTING olofess , <br />Ctill <br />her a �' <br />No. 75479 CD <br />Don Chesney, PE <br />Registered Civil Engine r #C75479 of Civil o� <br />e If Califot <br />ATTACHMENTS <br />APN and District Viewer Maps Denoting Project Location <br />EHD Percolation Test Rate Form with Test Location and Field Data <br />Page 2 of 2 <br />Chesney Consulting <br />