2021-205-E-Solid Waste-Full Circle Environmental-Walnut Grove Wastewater Disposal System

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DocuSign Envelope ID:81 E05E8E-EED7-43D3-8B8A-0811 OE72140A SECTION 33 34 00 - FORCE MAINS 4. The Contractor shall also pay the cost of flagmen or other expenses of the railroad in protecting traffic. He shall notify the railroad of the time that the work will be done and shall not begin work until authorized by railroad officials. 4.2 BORED ENCASEMENT INSTALLATION A. Encasement pipe which is dry bored under highways and railroads for installation of force mains shall be installed at the locations, to the gradients, and within the tolerances (if any), as shown on the plans. In event the encasement is installed off grade or seriously out of line, then another encasement pipe will be dry bored as close as practical to the original pipe with no additional compensation allowed therefor. The original encasement must be sealed with a watertight concrete plug (min. 3' deep)at each end. B. Any additional pipe or other work required for realignment of the force main with an alternate encasement location which was required due to improper gradient or misalignment in the original installation, shall be completed at the Contractor's expense. C. In event an obstruction is encountered during encasement boring operations which cannot be overcome, a second encasement shall be bored at a location designated by the Engineer. No additional compensation will be allowed for the second encasement installation. In event an obstruction is encountered in the second installation, at the direction of the Engineer, a third attempt shall be made to complete the encasement installation. Consideration will be given for additional compensation in event a third installation attempt is required. All abandoned encasement pipes shall be sealed as specified in paragraph 4.5.1 above. D. Pipelines installed through steel encasement shall meet specifications herein described and all Department of Transportation or Railroad specifications and guidelines for installing pipelines through steel encasement pipe. Upon insertion of the pipeline through the encasement pipe, the ends of the encasement pipe shall be sealed with brick and mortar. Brick and mortar shall be as herein specified, and the seal shall be such to withstand hydrostatic pressure from ground water and all backfill loads. Contractor shall provide means to prevent water line from floating within the encasement pipe. Grouting procedure will not be allowed. E. Casing pipe and joints shall be of leakproof construction, capable of withstanding railway or traffic loading. The diameter of the casing pipe shall be at least 2" greater than the largest outside diameter of the carrier pipe, joints, or couplings for carrier pipe less than 6" in diameter and at least 4" greater for carrier pipe, 6" in diameter and greater, unless indicated differently on drawings. Further, the casing pipe shall be of great enough diameter to allow carrier pipe to be removed subsequently without disturbing the case pipe and immediate areas. F. Steel encasement pipe shall be as specified in item 2.23 of this section. 4.3 TRENCH EXCAVATION A. Trenches for pipe shall be dug true to line and grade and to the following requirements. Depth of cover shall not be less than 3'-6" for pipe 10" and larger in diameter, measured to the top of pipe, unless shown differently on the profile or authorized by the Engineer. B. Sides of trenches shall be kept as nearly vertical as possible. They shall be at least 12", and not more than 24" wider at the top of the pipe than wide diameter of the pipe, plus sheathing where it is necessary. Where paving is to be cut, it shall be cut in advance of trenching 1'wider than the specified width of the trench. Orange County DAA PN R00592-225N2 Walnut Grove Wastewater System January, 2021 33 34 00-12