Rule 15-15-77-2-5.6.17 - System Design2. Determine the average daily flow from the residence: Number of bedrooms X 130 gallons per day3. Determining the size of the absorption area, basal area, side slopes, and maximizing length requirements: a. a. Sizing the absorption area The absorption area size shall be determined by the loading rate of the fill material. The fill material shall be coarse sand, 0.5-1.0 mm (USDA designation), and is the same as concrete sand (Section S-703, MS Standard Specification for State Aid road and bridge construction). The loading rate of this material is 1.2 gallons per day per square foot. Note: A fill material as heavy as a light loam may be used, but this will change the size of the absorption area size. Use the appropriate loading rate of the fill to calculate the absorption area. i. Example: Three (3) bedroom home @ 390 gallons per dayii. 390 gallons per day / 1.2 gallons per day per square foot = 325 square feet
iii. Absorption area = 325 square feetb. Sizing the basal area: Using the information gathered from the soil and site evaluation, determine the loading rate of the natural soil within two (2) feet of the surface. Use the heaviest textured soil loading rate to size the basal area. Divide the average daily flow from the residence by the loading rate of the natural soil. i. Example: Three (3) bedroom home @ 390 gallons per day a natural soil of a heavy loamii. 390 gallons per day /0.45 gallons per day per square foot = 867 square feet basal area15 Miss. Code. R. 15-77-2-5.6.17