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(a) The applicant has committed to a five-foot mining setback from the pipeline easement boundaries. In order to assure that the setback is maintained, the Division will require that the right-of way be delineated and marked. The applicant must provide a clearly written commitment to have the right-of--way surveyed by a licensed surveyor, and to erect a fence or other durable and clearly visible marker along the boundary. (b) The applicant has committed to mining temporary cut slopes at an angle no steeper than 1 h: I v. Typically, gravel pits are mined by excavation at the toe of a gravel bank, whereby the bank collapses progressively into the pit, usually at a near vertical slope. It has been the Division's direct experience that efforts to maintain the mined face at a slope no steeper than Ih:ly is rarely successful unless the operator mines the gravel by pushing material down the bank using a bulldozer, in which case safety considerations require that slopes no steeper than 2.Sh:l v or 3h:ly be developed. For this reason, the applicant must describe in terms of mechanics of earth moving the procedures to be used to mine at a 1 h: l v slope. It must be emphasized that under the mine plan as it is proposed, the Division would consider mining of the slopes parallel to the pipeline at a slope angle steeper than 1 h:1 v at any point during the excavation of the pit to be a serious violation for which an enforcement action would be immediately implemented. (c) As discussed above, the Division is satisfied that the proposed mine plan will be protective of the pipeline easement from the standpoint of bulk stability. However, small strains may be sufficient to adversely affect the pipeline, and for this reason the installation of two or three strain gauge emplacements on the pipeline would be a reasonable and prudent measure to detect any small movements in the pipeline that may occur. Eazly detection of small movements in the pipeline would allow for timely stress relieving measures that would prevent damage. In summary, the Division's position on the installation of strain gauges is that: The gas pipeline is a critical structure, and the consequences of a failure of the pipeline could be catastrophic. As such, a high degree of conservatism is called for in determining appropriate measures to protect the pipeline. The strain gauges are an accepted and easy-to-use pipeline-monitoring device that can be installed at a reasonable cost. The added degree of pipeline protection provided by strain gauges can be realized relatively inexpensively; requiring their installation a prudent addition to the proposed mine plan. Strain gauge installation and monitoring will require the cooperation of the pipeline operator. If such cooperation cannot be secured, the Division would consider proposals for alternate monitoring methods. Strain gauge specifics and altemate monitoring devices are discussed further below. (d) It is stated in the geotechnical report included with the application that Public Service Company was consulted concerning the design provided for haul road crossings over the pipeline easement. In order to satisfy the regulatory requirement for an engineering demonstration, the Division could accept either documentation that the proposed haul road is acceptable to Public Service Company, or a rigorous engineering evaluation.