Section 15080- Horizontal Directional Drilling

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15080 - 6/10 services rendered, including services required due to around-the-clock construction, the costs shall be borne by the Contractor. B. The Contractor shall obtain all necessary permits required for around-the clock operation from the various agencies having jurisdiction over the work area, if he intends to schedule work as such. Additionally, the Contractor shall furnish and install temporary noise barriers as required to comply with noise ordinances of the various agencies having jurisdiction over the work area. C. The Contractor shall have performed exploratory excavations or soft digs to locate existing utilities prior to commencement of work. 3.02 INSTALLATION A. General: 1. In general, the Work will proceed as follows with the horizontal directional drilling material being HDPE: a. Drill a pilot hole from one side of the bore path to the other side. The pilot hole shall follow the design centerline of the pipe with the path recorded and controlled using a specially designed instrument package situated behind the drill bit. b. The entire length of pipeline shall be fused and hydrostatically tested prior to pull back. c. A cutter/reamer shall be used to widen the drilled hole to its final diameter. A barrel reamer shall be used to smooth the wall of the hole and direct cuttings to the surface. A swivel shall be installed between the barrel reamer and the pipeline to ensure that no torque is transmitted to the pipeline while being pulled back. A bulkhead shall be fused to the end of the pipeline prior to attaching the swivel and barrel reamer. d. The HDPE pipeline shall be pulled back in a continuous operation at a constant speed until the pullback is complete. The pipe shall be filled with potable water during pull back unless otherwise approved by the OWNER. The pipe shall be pulled beyond the exit pit a minimum distance equilibrium before any other work is performed on the pipeline. e. Should the pipe become lodged during the pullback operation, the CONTRACTOR shall be responsible for all additional costs to dislodge the pipe. Additional costs may include, but shall not be limited to, replacement of overstressed sections of the pipe, additional excavation, environmental damage, or drilling of a new hole. All required work must be in compliance with all necessary permits. f. After the pipeline is in place, it shall be hydrostatically tested in accordance with the requirements of, Cleaning, Testing, and Disinfecting of Piping, Section 15060. B. Drill Path Geometry: 1. The CONTRACTOR is responsible for horizontal and vertical alignment of the pilot drill and final installed pipe. The pilot drill alignment shall conform to the pipeline alignments submitted by the contractor in Bore Path Report. The CONTRACTOR shall submit all proposed changes to the vertical alignment shown on the Contract Drawings for approval prior to commencing work. Under