SU0001451 - Laserfiche WebLink

Home Browse Search

4) Gravel should be placed at the base of the excavation. Within the gravel bed, 4 inch perforated pipe should be placed so that it distributes flow over to all parts of the filter bed evenly. Gravel cover shall cover the 4 inch perforated pipe. See the engineered septic system drawing for the layout of perforated pipe. 5) Non-woven filter cloth/fabric or equivalent should be used on top of the gravel to prevent the overlying sand from settling into the aggregate, thus reducing the void capacity. 6) The filter material shall consist of washed, clean, uniform sand in the size of D50= 0.1 to 0.15 mm (50%by weight smaller than or equal to 0.1 mm - 0.15 mm). 7) A local "sandy loam"produced by KRC Aggregate, Inc. Clements, California was evaluated for grain size and capillary rise. It was found to have a capillary rise of 15.3 inches and the D50 size is 0.15 mm. The dimensions of this sand are#30 sieve(0.6 mm), 100 percent passing, #50 sieve (0.3 mm), 97 percent passing, # 100 sieve(0.15 mm), 43 percent passing, # 200 (0.075 mm), 8 percent passing. This sand was found to be satisfactory for use as filter material. 8) The top of the bed surface should be slightly sloped for positive drainage. 9) Any surface runoff from adjacent areas should be diverted around the system by berms or drainage swales. The purpose of this review is to ensure that the septic field is not sited in an area that will accumulate runoff during rain storms. 10) The septic field is to be located in an area free and clear of vehicle use. Essentially, compaction of the filter bed soils is not permitted. 11) The planting of grasses, flowers, or soft plants is acceptable and recommended on the bed to promote evapotranspiration. 12) The septic tanks are required to be pumped and cleaned a minimum of every three (3) years. Access to the septic system disposal field by service equipment should be maintained. 13) It is not acceptable to dispose of mineral salt from a-water softener into the septic field. 14) A 100% septic system replacement area is required. The replacement area must remain undeveloped. Access to the septic system disposal field and replacement area by service equipment should be maintained. —Calculations,Page 4—