SU0006571 SSNL - Laserfiche WebLink

Home Browse Search

LEACHLINE REQUIREMENT CALCULATIONS BASED ON SAN JOAQUIN COUNTY SEWAGE STANDARDS FOR COMMERCIAL SEPTIC SYSTEMS: Base Tank Capacity= 1,200 gal. ADF=215 d Leachline Equivalent Requirement= 1,200 gallo TC+215 ADF x 0.225 ndy silt Soil Factor(SF)at native soil-effluent interface=320 lineal feet of leach i ed. Proposed: 3 x 50 ft long leachlines= 150 LFLL. Each 2 ft wide x 12 ft long x 10 ft deep sump is equivalent to 60 ft of leachline: 1 sump at the end of each leachline= 3 sumps x 60 ft= 180 LFLL 150 LFLL+ 180 LFLL=330 Lineal Feet of Leachline to be installed. 100% Reserve Replacement Area: The primary area is calculated to be 2,728 sq ft. The 100%replacement area can be accommodated to the north/northwest(1,500 sq ft),east and south(1,634 sq ft)of the primary leachfield area(Total reserve area= 1,500+ 1,634=3,134 sq ft). IV. CONCLUSIONS AND RECOMMENDATIONS SSS§ 5.4. The soils underlying the proposed leachfield disposal area to serve the Sunset Kennels show poor permeability at the typical leachline depth of 36 inches,but exceptional permeability at the proposed sump depth of 10 feet. As referenced, the sumps must be installed to a maximum depth of 10 feet, thus maintaining a 10-foot separation distance between the bottom of the sump and the water table as measured by sounding the new domestic well. This separation distance also allows a 2.8 foot safety margin: 22.8 f water table depth minus 10 ft separation distance= 12.8 ft 12.8 ft - 10 ft deep sump = 2.8 feet.,/ NLS§ 4.2, SSS§ 6.7. From the soil chemistry test results, it appears that denitrification potential will be medium based upon the clay content and the slight decrease in nitrate-nitrogen content through the soil profile. This medium denitrification potential in combination with comparatively shallow-rooted landscape plants such as grasses in the leachfield area should also reduce nitrate impact by evapotranspiring and mineralizing a percentage of the effluent during favorable weather times of the year(i.e., April through September). ✓The well water analytical chemistry results obtained from the old original on-site domestic well indicates the nitrate impact to the underlying shallow aquifers is high at 76.1 ppm nitrate. This impact is probably due to the agricultural production land upgradient to the project site. The depth of the old well is unknown. The new well, with a depth of 290 feet contains no nitrate and is screened from 250 ft to 290 ft. SSS§ 6.8. The Average Daily Flow is calculated to be 215 gals/day from the entire project. The Application Rate at the native soil-effluent interface is 0.200 gals/ft'/day from the obtained perc rate of 125 min/in at the 36 inch perc test depth. At the sump depth of nine feet, an application rate of 0.971 gals/ft2/day from the perc rate of 5.6 min/in was obtained. 12 Chesney Consulting