410 IAC 6-10.1-96 Elevated sand mound on-site sewage systems: construction of the aggregate bed

Sec. 96. (a) The surface of the INDOT Specification 23 sand at the sand/aggregate interface shall be smooth and free of ruts and depressions before the placement of the aggregate. (b) The depth of aggregate in the aggregate bed from side to side and end to end shall be at least: (1) six (6) inches below the pressure distribution laterals; (2) plus the outside diameter of the pressure distribution laterals; (3) plus two (2) inches above the pressure distribution laterals. (c) The aggregate bed shall be covered with a barrier material which meets the minimum requirements of section 77 of this rule. The barrier material shall cover the aggregate bed from side to side and from end to end.