Illinois Administrative Code
Title 77 - PUBLIC HEALTH
Part 906 - PRIVATE SEWAGE MOUND CODE
Section 906.60 - Distribution System (for sewage flows of less than 800 gallons per day)
Current through Register Vol. 48, No. 12, March 22, 2024
a) Piping System. The piping distribution system for the mound shall consist of a manifold pipe and small diameter laterals with perforations. The perforations shall be drilled at 30"-36" intervals along with the invert of the lateral. Perforations shall be installed perpendicular to the pipe axis. Perforation diameters shall be between 3/16" and 1/4". If the distance between the end of the lateral and the nearest perforation is greater than 1/2 the perforation spacing used, another hole shall be installed in or near the end cap of the lateral. A typical distribution system of a mound is shown in Appendix A, Illustration E. For a trench system, one lateral shall be required per trench; for a bed system, up to 3 laterals may be used. Laterals shall extend to within 6 inches of the end of the bed or trench. Lateral spacing shall be a maximum of 3 ft. for beds in small mounds only (1-4 bedroom sized system). Pipe diameter will depend upon the length of bed or trenches. The allowable lateral lengths for various size diameter pipes and various hole spacings are given in Appendix A, Exhibit D. The system shall be designed and placed so that the laterals and manifold drain after every dosing. If the mound is downslope of the pumping chamber, the manifold shall be on top of the laterals so the manifold drains, or cross-to-cross construction used. For systems which are to treat a flow of more than 800 gallons per day, the manifold and lateral network must be designed in accordance with Section 906.70. All piping shall be Schedule 40 Polyvinyl Chloride (ASTM Standard D1785/76) or Schedule 40 Acrylonitrile/Butadiene/Styrene (ASTM Standard D1527/77).
b) Pumping System. The components of the pumping system shall consist of the pumping chamber, pump, pump controls and alarm system as shown in Appendix A, Illustration F. The dosing volume shall be ten times the total lateral pipe void volume or one-fourth the estimated daily sewage flow, whichever is greater. Appendix A, Exhibit F lists the void volumes for various sizes of pipe. The daily volume of sewage shall be determined using Appendix A, Illustration A of the Private Sewage Disposal Code (77 Ill. Adm. Code 905).