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connections, to be paralleled or crossed prior to the start of directional drilling <br />operations <br />5. Modify alignment, depth or grade as necessary to avoid utilities and minimize the <br />number of peaks and valleys along the alignment <br />6. Expose all utilities that will be crossing with horizontal directional drilling <br />7. All major utilities (high pressure gas, fiber optic, high voltage electric, major pipe <br />lines, water and sewer lines, etc.) should be exposed every 100 feet at minimum, if <br />parallel within five feet of excavation area to verify depth and location of the utility <br />8. The utility owner should be contacted immediately if location is not accurate <br />B. Surface Preparation <br />1. Per specification Section 312333, Trenching and Backfilling <br />3.2 INSTALLATION <br />A. General <br />1. Install pipe by the directional drilling methods unless conditions require open trench <br />installation. Obtain Owner approval prior to open trench construction. <br />2. Install pipe by continuously pulling the pipe into place from insertion point to exit <br />point without causing damage to the pipe being inserted. Provide lubricants as <br />required by the pipe manufacturer to avoid stressing the pipe past its elastic limit. <br />Contractor to provide rollers or alternative apparatus to prevent damage to the pipe. <br />3. Provide installation and receiving pits as necessary for complete installation of the <br />pipe. The excavation of the installation and receiving pits shall be incidental to the <br />work. <br />4. The Contractor shall not start the pullback unless it can be completed without <br />interruptions. Contractor shall coordinate scheduling with the Owner /Engineer. <br />- -- 5. The Contractor shall provide sediment and erosion control measures to prevent <br />drilling fluid or borehole cuttings from entering the adjacent parcels to the <br />construction limits. <br />6. The pilot hole shall establish the horizontal plane of the pipeline. A plot of length <br />versus elevation versus left/right variance will dictate the actual as -built plan and <br />profile of the pipeline. Data feedback and electronic guidance systems shall be used <br />to provide confirmation of position. <br />7. Reaming shall consist of using an appropriate tool to open the pilot hole to a slightly <br />larger diameter than the carrier pipeline. The percentage oversize shall depend on soil <br />types, soil stability, depth, drilling fluid hydrostatic pressures, etc. Normal over sizing <br />shall be from 120 to 150 percent of the product pipe diameter. Drilling fluid shall be <br />forced down the hole to stabilize the hole and to remove soil cuttings. The Contractor <br />shall carefully monitor the reaming operations to prevent damage to adjacent utilities. <br />- 8. The Contractor shall maintain accurate alignment and grade control and shall <br />determine the pipe elevation (above mean sea level) at intervals not exceeding 30 feet. <br />9. The pipe shall be installed by continuously pulling and /or pushing the pipe into place <br />- -. -. through the drilling fluid along the reamed hole pathway from insertion point to exit <br />point without causing damage to the pipe and pipe joints being inserted. The pullback <br />speed shall be within the pipe manufacturer's recommendations. Drilling <br />fluid /lubricants shall be provided as required by the pipe manufacturer's <br />recommendations and specifications to avoid stressing the pipe and joints past the <br />33 05 23.13 - 4 <br />