A chamber disposal system that disposes of effluent from a septic tank installed after the effective date of this chapter shall meet the following requirements:
(a) The minimum length of any leach trench being used as a component of a chamber system shall be at least 200 linear feet.
(b) The chambers shall have IAPMO approval for use in an on-site wastewater treatment system and shall be installed in compliance with section 68.340.
(c) Each chamber shall have a minimum width of 18 inches to provide the equivalent trench bottom absorption area of an 18-inch wide leach trench. Chambers less than 18 inches wide may be used, but will require a correction factor to provide the equivalent trench bottom absorption area of an 18 inch wide leach trench. The chambers shall be installed in a trench 24 to 36 inches deep and be located no closer than 10 feet on center from any adjacent line.
(d) Leach trenches and chambers shall be level, with no more than 2 inches per 100 linear feet of variation in grade.
(e) Chamber trench depth may exceed 36 inches below the ground surface when percolation testing substantiates adequate soil conditions exist at the depth approved to receive and treat effluent. Clean washed rock or gravel, grading 1 to 1-1/2 inches, shall be added to the trench below the chamber to prevent the chamber depth from falling below the approved depth. The maximum trench depth shall not exceed 60 inches unless steep slopes on the property make it impracticable to install the system without placing the chamber trenches below 60 inches. If it is necessary to install leach trenches more than 60 inches below the surface, the property owner shall only be allowed to exceed 60 inches if the installation complies with resource protection provisions in sections 86.601 et seq., grading provisions in sections 87.101 et seq. and the California Occupational Health and Safety Act.
(Added by Ord. No. 9273 (N.S.), effective 12-15-00; amended by Ord. No. 10136 (N.S.), effective 4-15-11)