Rule 511-3-1-.18 - Standards for Non-Conventional On-Site Sewage Management Systems(1) The Department shall review absorption field products that differ in design from the conventional on-site sewage management system. The following standards will be used to determine equivalency to the conventional on-site sewage management system: (a) The design infiltrative surface is the wetted trench bottom area.(b) Due to the combined effects of compaction, contact area and fines associated with gravel aggregate, the effective infiltrative surface area shall be reduced by an estimated 50%.(c) The minimum amount of effective trench bottom infiltrative surface area per linear foot shall be equivalent to the conventional 36-inch wide gravel system.(d) Sidewall area shall not be considered for design reduction. The minimum amount of effective sidewall infiltrative surface area per linear foot shall be equivalent to a conventional 36-inch wide gravel system.(e) The minimum storage volume required for a system shall be equivalent to a conventional 36-inch wide gravel system.(f) The design absorption area required is based on the most hydraulically limiting soil horizon that comes into contact with the infiltrative surface of the sidewall, trench bottom, and for a distance 1 foot below the absorption trench bottom.(2) The infiltration area for conventional 36-inch wide gravel trench absorption shall be considered to be as follows: (a) Sidewall Infiltration Area: 2 sq. ft./ft x .50 = 1 sq.ft. / linear foot(b) Trench Bottom Infiltration Area: 3 sq. ft./ft x .50 = 1.5 sq.ft. / linear foot(c) Storage Volume: 3 cubic feet / linear foot x 7.48 gallons / cubic foot x .35 = 7.85 gallons / linear foot (3) Lots approved for development based on a reduction in absorption trench length up to 50% shall continued to be approved and permitted for up to a 50% reduction in absorption trench length provided the lot is part of a recorded plat or part of a preliminary development plan submitted to the County Board of Health within one year of the April 1, 2007 rule adoption. Preliminary plans must include proposed lots and streets with lot identifications, lot dimensions, and square footage; a topographic map with water courses and flood plain identified; a level 3 soil report; the location of the water supply system, right-of-ways, easements and utilities; and the name, registration number and seal of the professional surveyor or engineer.Ga. Comp. R. & Regs. R. 511-3-1-.18
O.C.G.A. Secs. 12-8-1, 31-2A-6, 31-2A-11.
Original Rule entitled "Standards for Non-Conventional On-Site Sewage Management Systems" adopted. F. Dec. 20, 2013; eff. Jan. 9, 2014.