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IV. CURRENT OWTS OPERATIONAL PARAMETERS AND COMPONENTS SSS§ 3.7. Currently, all domestic wastewater influent sources flow into a 3,600 gallon septic tank and then gravity to the large sump structure in the NWC of the property. A conventional leachfield with leachlines is adjacent to the north of the septic tank. The previous use of these leachlines is unknown and may not have been used since the sump structure was installed in 1996. Sizing for the 3,600 calculated tank capacity (CTC) is based on SJC EHD Form 42-01-004 and by using the EHD specified ADF in gpd: 1,125 gal tank + (2,220 gpd ADF x 0.75) = 2,790 gals. Therefore, the 3,600 gal septic tank capacity is adequate but still must be pumped quarterly to due observed severe solids build-up. OWTS DISPOSAL AREA CALCULATIONS The following calculations determine the adequacy of the existing leachlines to accept the daily wastewater flows and is based on the infiltrative area of the leachlines. Taking the acceptance rate of the soil from the 36" deep perc test at 0.467 gallons/ft2/day and applying this rate to the infiltrative area of the leachlines: There are 5 leachlines, each 90 ft long. Assigning 4 sq ft/ LF of leachline for infiltration area =5 x 90 = 450 LFLL x 4 ft2/ LF = 1,800 ft2. 1,800 ft2 x 0.467 gallons/ft2/day = 840.6 gpd the leachline can theoretically assimilate. Given that the meter reading on the domestic well totaled 26,987 gallons for the year 2020, equivalent to 74 gpd, on average. Consequently, the leachlines should manage anticipated daily flows. The sump structure has a surface area of 48 ft x 15 ft = 720 ft2 x 5 ft deep = 3,600 ft2. The application rate at the 8 ft depth was 0.729 gallons/ft2/day. Therefore the sump can theoretically manage 3,600 ft2 x 0.729 gallons/ft2 /day = 2,624 gpd. Page -7- Chesney Consulting