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F content at the time of ripping is critical and should not be too wet or too dry71n��a be perpendicular(east to west)to the surrounding land contour and only witd/native soil interface. After ripping and before emplacement of the peat ma, it is imperative that no equipment be driven over this area. C. CALCULATION OF MOUND DIMENSIONS BASAL LOADING RATE Due to the long-term acceptance rate (LTAR) anticipated, a conservative basal loading rate employed for design purposes. Consequently, a loading rate figure of 0.33 gallons/ftZ/day w used. HYDRAULIC LINEAR LOADING RATE From the percolation tests and direct observation of the soil from the infiltration test, it was evident that there was both vertical and lateral flow of water. A linear loading rate of 15 gallons/lineal foot/day will be used. SAND MEDIA/GRAVEL BED SPECIFICATIONS AND LOADING RATE The filter media is a sand material that underlies the gravel bed. The sand media should be tested by an engineering laboratory, or be certified by the sand supplier before emplacement. A sieve analysis (ASTM C-33 Specifications) should demonstrate the sand media material must not have more than 20%(by wt.) of material greater than 2 mm dia. and no more than 2% (by wt.)passing the No. 200 sieve. Effective Diameter (d10) should be 0.20 to 0.30 mm with a Uniformity Coefficient(D60/Djc) of approximately <4. The sand media loading rate complying with the specifications above is 1.6 gpd/ft2. The gravel bed on top of the sand media shall also be tested for conformance with the following size distribution: 3/8 in. washed pea gravel to 1.5 in. washed drain rock. A geotextile filter fabric must be placed over the top of the drain rock bed as noted on the Design Plans. AGGREGATE ABSORPTION AREA(A) A= 1.700 MAX ADF Based on Sundays A= 1063 ft'(use 1500 fig; 15 ft wide x 100 ft long) 1.6 gpd/f(from above) BASAL AREA WIDTH(A+I+.J) A+I+J=Linear Loading Rate=Basal Loading Rate(Based on Long-Term Acceptance Rate-LTAR) = 15 gals/day/ft-0.33gallons/ft2/day =46(say 50 ft)ft Use A= 18 ft, I= 15 ft and J= 18 ft MOUND DEPTHS Peat Material=4 in. Washed Sand= 12 in. Aggregate Absorption Area thickness=9 in. (6 in.of aggregate below the laterals, 1 in.for pipe height and 2 in.for cover over pipe=9 inches) Thickness of Topsoil(Fill and Cap)over the Aggregate Absorption Area = 12 in. Thickness of Topsoil(Fill and Cap)on the sides of the mound system=6 in. 14 Chesney Consulting