2012-03-07_PERMIT FILE - C2010088 (24)

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FJPVA;-ICSN' `. t Pipe laying shall begin at the downstream end of the culvert. The bell or groove end of the pipe shall be placed facing upstream. No culvert shall be placed in service until a suitable outlet is provided. 8.22.10 BACKFILLING AND COMPACTION - Backfill materials shall be placed simultaneously on both sides of the pipe culvert in uniform layers not exceeding six inches (6 ") in thickness. For multiple pipes the backfill shall be placed simultaneously in uniform layers between and outside of the pipes. Each successive layer shall be compacted to not less than 95% (Modified Proctor) of maximum density as determined by ASTM D 1557, with moisture content adjusted if necessary, and each six inch (6 ") layers shall be properly compacted before the next layer is placed. Backfilling shall be started and completed as quickly as possible after the pipe culvert has been assembled and placed on its bed. Special care must be taken to obtain adequate compaction under the pipe culvert haunches; however, care must be exercised to avoid lifting of the pipe culvert as the result of tamping to compact material under the haunches. Where pipe culvert is placed in a confined area, making it difficult to obtain adequate compaction under the pipe culvert haunches through tamping, a Controlled I,ow- Strength Material (CLSM) fill may be used, see UP Bridge Standard Plan No. 680000, Sheet 2 of 2 (this plan refers to steel pipe but the CLSM fill section shall also apply to concrete pipe. All backfill material placed around and adjacent to pipe culverts to a point at least one foot above the top of the pipe culvert shall consist of sand, gravel, sandy -clay, or a combination thereof, free from all vegetation and rock or lumps greater than one and one -half inches (1 -1/2 ") in diameter in their greatest dimension. Granular material containing a small amount of silt or clay is an ideal backfill material because it makes a dense, stable fill. Where granular material is used for backfill, the ends of the pipe culvert embankment shall be sealed with well- tamped clay to prevent leaking and infiltration of water along the pipe culvert. Materials used to complete the embankment over the pipe culvert should be essentially the same as the materials used for the pipe culvert backfill and should be placed and compacted in the same manner as pipe culvert backfill materials are placed. Such material must be used to complete the embankment at least to a height over the top of the pipe culvert equal to the nominal diameter of the pipe culvert, or if the height of the completed embankment over the top of the pipe culvert is less than the nominal diameter of the pipe culvert, then such material must be used to complete the embankment. The pipe culvert must be protected from damage during the entire construction period, especially if heavy compaction and/or construction equipment is used. Heavy equipment shall not be operated over the pipe culvert until it has been covered with compacted backfill material to a depth of twenty -four inches (24 "). Copies of all compaction tests shall be supplied to the Engineer. 8.22.11 REMOVAL OF EXISTING IIEADWALLS OR CULVERTS IN PREPARATION FOR EXTENSION OF EXISTING PIPE CULVERTS - The Industry shall remove existing headwalls and/or culverts in whole or in part as shown on the Drawings and in the Specifications. The Industry shall perform all work called for, as shown on the Drawings and in the Specifications, which may be necessary to adapt existing pipe culverts for extension or reconstruction, including required excavation and backfilling. Except as otherwise provided for 39