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The Munger Canyon site is located in an area which characteristically receives less than <br />ten inches of rainfall annually. This may be detrimental to revegetation. For this reason, <br />surface manipulation of the soils to enhance moisture retention and reduce erosion during <br />reclamation will be initiated by the applicant prior to seeding. Stipulation 8 was attached <br />to the permit. during the 1985 Permit Revision No. 1. The operator complied with this <br />stipulation with submittal and Division approval of Technical Revision No. 4. <br />As previously noted, no topsoil was salvaged from the existing disturbances. During the <br />life of the mine, minor amounts of soil sloughed off the haul road slopes. The soil has <br />been stored in the topsoil stockpile area, as well as on the mine bench. This material is <br />not considered topsoil, but Grand Valley was permitted to store the material in the <br />stockpile because analysis indicated that the material was suitable for reclamation. Grand <br />Valley will use this material on the mine site area, where it will be trucked to the mine <br />site and spread to approximately one foot thick. The material will also be used as top <br />dressing in areas where excessive rock is exposed on the surface after recontouring. <br />With acceptance by the applicant of the above stipulations, the operation will be in <br />compliance with the requirements of this section. <br />The Division is proposing to grant a variance from topsoil removal in accordance with <br />Rule 4.06.2(2)(a). This variance applies to the mine bench azea and access road that were <br />constructed prior to August 3, 1977. No topsoil was salvaged or required to be salvaged <br />at the time of the disturbance. <br />V. Sealing of Drilled Holes and Underground Openings <br />The appropriate information satisfying these requirements appeazs in Sections 2.1 and 3.7 <br />of the application (Volume I). The applicant has committed to conform with al] the <br />applicable regulations regazding the sealing and management of borings. <br />The applicant proposes to abandon the portals at the Munger Canyon Mine by <br />constructing a 16-inch-thick double concrete block wall, keyed a minimum of 12 inches <br />into the floor, roof and ribs or an MSHA approved concrete foam structure. This wall <br />will be constructed at a minimum of 25 feet from the surface. Temporary seals of <br />MSHA-approved concrete foam were installed in the portals during 1992. When the <br />portals require permanent sealing, the remaining portion of the portal will be backfilled <br />with incombustible materials. As such, the proposed technique conforms with the <br />M.S.H.A. regulations as stated in 30 CFR 75-1711, Federal Code of Regulations. The <br />technique will also satisfy the requirements of the permanent regulatory program. <br />Drainage will not occur at the portals, based upon information submitted with the <br />application. <br />39 <br />