(A) Granular material, where required, shall comply with § 211.02 of the INDOT Standard Specifications. Maximum stone size shall not exceed one inch or the maximum size recommended by the pipe manufacturer, whichever is smaller.
(B) Backfill and bedding for trenches shall consist of the various materials classified in this division (B) below as specified herein:
(1) Class I: Angular, six to 40 millimeters (one-fourth to one and one-half inch) graded stone such as crushed stone. A No. 8 gravel possessing a minimum 50% mechanical crush count and meeting the following nominal sizes and percents passing will be considered an equivalent Class I material: 100% passing a one-inch sieve; 75-95% passing a three- fourths-inch sieve, 40-70% passing a one-half-inch sieve, and 0-15% passing a No. 4 sieve;
(2) Class II: Coarse sands and gravel-sand mixtures with a maximum particle size of 40 millimeters (one and one-half inches), including variously-graded sands and gravels containing small percentages of fine, generally granular and non- cohesive, either wet or dry. Soil types GW, GP, SW and SP are included in this class (Indiana Department of Transportation (INDOT) Classification for Structural Backfill);
(3) Class III: Fine sand and clay gravels, including fine sands, sand-clay mixtures and gravel- clay mixtures. Soil types GM, GC, SM and SC (ASTM D2487) are included in this class. These materials will not be accepted as pipe bedding; or
(4) Class IV: Silt, silty clays and clays, including organic-clays and silts of medium to high plasticity and liquid limits. Soil types MH, ML, CH and CL (ASTM D2487) are included in this class. These materials will not be accepted as pipe bedding.
(C) Crushed stone material shall be No. 53 complying with § 904.03 of the INDOT Standard Specifications.
(Ord. 2010-3, passed 10-6-2010)