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The LRP is inspected quarterly by a qualified professional specialist under the direction <br /> of a professional engineer, experienced in construction of similar earth and waste <br /> structures. Features inspected are erosional, drainage, structural, reclamation, and <br /> general compliance and other miscellaneous features (4.10.2(1)). <br /> In January of 1997, MCC submitted an application for TR-79 which proposed the <br /> addition of the RPE on approximately 20 acres immediately east of the LRP, on the <br /> opposite (east) side of Sylvester Gulch. TR-79 was approved in 1997. The plan is to <br /> develop the pile in stages. Phase I is the buildout which involved the removal of topsoil, <br /> initial grading, construction of a dual-cell sedimentation pond, liner, and underdrains <br /> along with run-off control. Phase II was the initial refuse emplacement. Phase III will <br /> involve the main build-out as the pile will proceed up the hillslope to the north at a slope <br /> of 2.5 to 1. Sediment controls will be extended to the west, south and east sides. <br /> Ultimately Phase IV will be the completion of the pile with a capacity of 1,384,102 <br /> cubic yards total. <br /> The sedimentation ponds and initial run-off control berms and ditches were completed <br /> prior to the beginning of Phase I. Topsoil was placed north of Highway 133 in an area <br /> known as the north soil storage area(NSSA). Subsoil from Phases I and II were used in <br /> the development of the Sylvester Gulch facilities area(PR-7). Subsoil removed in <br /> phases III and IV will be sufficient for reclamation of the RPE area itself and will be <br /> placed in a stockpile to be determined prior to the beginning of Phase III. <br /> The RPE area of Phases I and II is lined with high-density polyethylene liner. An <br /> underdrain, designated as a rock drain, is used for collecting refuse fill drainage. The <br /> liner will allow subsurface water to migrate into the rock drain system and be routed to <br /> the RPE sedimentation pond. Phases III and IV subsurface will not be lined because of <br /> the steeper slope grade (2.5H:IV) and the greater clay content of the colluvium. <br /> The reclamation of the RPE was approved with an average total of 18 to 24 inches of <br /> subsoil and topsoil. A variance to cover the LRP was approved through TR-43 in July, <br /> 1987. That variance was applied also to the RPE. As the RPE is graded and covered <br /> with subsoil and topsoil, it will be revegetated with the approved permanent seed mix. <br /> The seeding will be done either by broadcast or by hydroseeding and then mulched. <br /> Interim and final revegetation will be conducted in the same manner as for the LRP. <br /> The haul road for the RPE will be reclaimed at the end of mine life to approximate <br /> original contour. <br /> A small waste pile at the Lone Pine ventilation fan site was approved through TR-69 on <br /> August 12, 1994. The pile stores refuse from the development of that facility. It covers <br /> 0.7 acres, storing 17,000 cubic yards of refuse. A subdrain system was installed. The <br /> pile was covered with three feet of subsoil and one foot of topsoil and reclaimed. <br /> The RPEE was approved with TR-121 in 2010, and was under construction in 2011. <br /> This pile has an approximate maximum capacity of 4 million cubic yards. Colluvium is <br /> to be left in place underneath the refuse pile, and an underdrain is to be constructed on <br /> top of the colluvium after 24 inches of soil is removed and stockpiled. Ditches designed <br /> for a one hundred year storm will be constructed on either side of the pile. These ditches <br /> 52 <br />