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8 <br />Transportation Infrastructure using a plow type installation process. Do not install pipeline by <br />jack and bore process. When installed using an open cut, the bedding and pipe zone of the pipeline can be backfilled with material excavated for pipeline placement. Compact backfill to a minimum ninety-five percent (95%) of maximum dry density. For directional drilling, conform to the requirements for crossing the DCAI. <br />(c) Geotechnical calculations – Prepare and submit calculations to demonstrate that the Natural Gas Transportation Infrastructure has adequate strength, flexibility, and slack to withstand the expected loading, rebound, and settlement beneath levees and other fills and that the selected depth accounts for rebound and settlement. The Utility shall base the geotechnical calculations on the DCAI <br />cross section at Station 645+00+/- as shown in Exhibit 1. The right and left EMBs shall be compacted to ninety-five percent (95%) of maximum dry density as determined by the standard proctor. <br /> <br />(d) Design requirement – Design and construct the Natural Gas Transportation Infrastructure crossing the IDF Line of Protection in accordance with the following USACE publications. In the case of a conflict with stated requirements, design and construct in accordance with the more stringent requirement, unless <br />otherwise agreed to by the Parties hereto. <br /> (1) Engineer Manual, EM 1110-2-1913, "Design and Construction of Levees" <br /> <br />(e) Manual Isolation Valves – Install manual isolation valves for emergency closure that are consistent with the Utility’s safety requirements in a location accessible by the Utility to the west of the Project Site and to the east of the Project Site as identified on Exhibit 2 attached hereto. Manual isolation valves may be placed <br />outside of the Project Site. Provide security and protective features as required by <br />the Utility. <br />(f) Casing for utilities – Casing is not required for the Utility’s crossings. <br />(g) Grouting – Where horizontal directional drilling is used to cross the DCAI and <br />IDF Line of Protection, grout the annular space between the borehole and the <br />casing or pipe with cementitious grout for fifty (50) linear feet from the end of the <br />pipe at the entrance and exit pits. Inject grout into the annular space at multiple <br />points around the circumference of the pipeline throughout this 50-foot length. <br />Install baskets or other techniques on the pipeline just beyond the 50-foot length <br />to prevent the grout from flowing more deeply into the hole, but completely fill <br />the annular space between the basket and the ground surface. Limit grout pressure <br />to the mud pressure used for the directional drill. <br /> <br />(h) Crossing identification – Install permanent utility markers in adequate quantity to <br />clearly identify the existence and location of the Utility’s pipeline facilities. If <br />requested by the Metro Flood Diversion Authority, additional markers will be