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conforming to ASTM Designation C33 -Ila requirements. This material shall be used primarily for pipeline and manhole foundations. B. Type 2 - Type 2 material shall be unclassified material obtained from w the Contractors excavations and approved by the Engineer. The material shall be substantially free from wood, roots, humus, peat, muck, and r other organic materials, and shall not contain clods, stones, masonry ] rubble, and the like, greater than 6 inches through the largest dimension. In general, the material shall consist of sand, loam, sandy- loam, clayey - sand, gravel, or crashed stone. C. Type 3 Type 3 material shall be select granular material, free from organic matter, of such size and gradation that the desired compaction can be readily attained and shall meet the requirements for A3 material according to the Revised Bureau of Public Roads Classifications. Material from the Contractor's excavations may be used, if it meets the above requirements. Otherwise it must be imported. 7. .BEDDING AND FOUNDATIONS A. CLASS A (CONCRETE CRADLE OR CONCRETE ARCH BEDDING) 1) This class of bedding shall be used only where specifically shown in the Drawings or directed by the Engineer. Ii the use of a concrete cradle is required the pipe shall be bedded in a monolithic cradle of ! a 1,540 PSI concrete with a minimum thickness equal to 114 the outside pipe diameter or to a minimum of four inches under the barrel, whichever is greatest, and extending up to the sides of the pipe to a height equal to 112 of the outside pipe diameter. The cradle shall have an overall width equal to 1-1/4 of the outside diameter of the pipe or a minimum width equal to the outside diameter of'the pipe plus eight inches, whichever is greater. 2) If a concrete arch is required, the pipe shall be embedded in carefully compacted Type I material having a minimum thickness equal to 1/4 the outside pipe diameter or to a minimum of four inches under the barrel, which ever is greater, and extending up the sides for a height equal to 1/2 of the outside pipe diameter. The top half of the pipe shall be covered with a monolithic Class C concrete arch having a minimum thickness equal to 1/4 the outside diameter of the pipe or a minimum of four inches over the crown of the pipe, whichever is greater, and extending down the sides for a depth equal to 1/2 of the outside pipe diameter. The arch shall have an over all width equal to 1 1/4 of the outside diameter Iw of the pipe or a minimum width equal to the outside diameter of the pipe plus eight inches, whichever is greater. B. CLASS B (FIRST-CLASS BEDDING) 1) Where Class B Bedding is required, the trench shall be excavated below the planned bottom of the pipe to a depth equal to 1/4 the nominal diameter of the pipe, or 6 inches, whichever is greater. The over excavated depth shall be backfilled using either Type 1 or Type 3 materials carefully compacted and shaped using hand tools so as to provide a uniform support for the lower portion of the pipe barrel. Shaping under the pipe bells shalt be so that the bell does not support the pipe and joints can be