(l) The following systems or site characteristics shall require a design by an engineer:
- (a) The system has a design flow of more than 1,800 gpd of sewage. See 420-3-1-.52 Design Flow and Wastewater Concentrations.
- (b) The system will serve a food establishment that is classified as a Priority Category 3 or 4 establishment by the Board's Rules for Food Establishment Sanitation, Chapter 420-3-22, Ala. Admin. Code.
- (c) The system will receive high strength sewage. These systems do not have to use advanced treatment unless the design flow is over 1,800 gpd, but the field shall be sized according to 420-3-1-.55 Gravel Field Standard EDF Sizing for Establishments.
- (d) The site characteristics prohibit the use of a Conventional OSS. See Table 7 and Table 18.
- (e) The site characteristics set forth under 420-3-1-.51 Lot Modification – Planned and Unplanned stipulate engineer involvement.
- (f) The lot is smaller than the minimums set out in 420-3-1-.10 Minimum Lot Size Requirements.
- (g) Slopes over 25 percent in the EDF area.
- (h) A system that does not meet the definition of a Conventional OSS.
- (i) An Innovative EDS.
Author: Thad Pittman, Matthew Conner, Ken Stephens, Bob Bright
Statutory Authority: Code of Ala. 1975, §§22-2-2(4); 22-2-2(6); 22-10-1, et seq.; 22-26-1 et seq.
Editor’s Note: Previous Rule .08 was renumbered .09 per certification published December 30, 2022; effective February 13, 2023.
History: New Rule: Filed January 19, 2017; effective March 5, 2017. Repealed and New Rule: Published December 30, 2022; effective February 13, 2023.