2015-10-13_REVISION - C1981014 (7)

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SOUTHFIELD MINE PHASE II BOND RELEASE MINE SITE TOPSOIL REPLACEMENT THICKNESS SUMMARY AND PRE -FERTILIZER FERTILITY SAMPLING RESULTS INTRODUCTION For Phase II bond release, the Division of Reclamation, Mining and Safety Guideline Regarding Selected Coal Mine Bond Release Issues requires submittal of "a map or description of topsoil replacement thickness, and replacement documentation methodology". The Mine site, consisting of the Portal Area and remaining active RDA, was reclaimed during 2002 in accordance with the approved reclamation plan. The Portal Area was backfilled and graded with the exception of one sediment pond. At the RDA, subsoil and topsoil were placed separately to achieve the required total cover depth. Most of the RDA had been previously reclaimed on a contemporaneous basis involving subsoil and topsoil cover placement and revegetation beginning in 1983. Documentation of the previous reclamation work is shown in applicable Annual Reclamation Reports. Permit application Section 2.05.4, Redistribution of Topsoil, addresses topsoil sources, replacement methodology, replacement thickness, and fertility sampling at the Mine site. Topsoil replacement depth requirements varied throughout the Mine because of previous disturbance in the Portal Area and subsequent limited removal and stockpiling of topsoil. In order to achieve adequate overall topsoil placement thickness, EFCI obtained approval prior to reclamation to utilize an existing topsoil stockpile on the adjacent reclaimed Newlin Creek mine area, and to excavate a soil borrow area next to the RDA. Specific topsoil placement thickness requirements were as follows: Portal Area: approximately 6 inches Pond 3 area: approximately 6 inches RDA borrow area: approximately 6 inches RDA: based on soil volume excavated, approximately 12 inches average During reclamation of the Portal Area and Pond 3 area, topsoil was placed on regraded areas that were intentionally left in a roughened condition after backfilling and grading operations. All topsoil was placed by tractor scrapers and tracked dozers from existing stockpiles and, at Pond 3, from the borrow area. A road grader was utilized in some areas to insure that a uniform depth was achieved. EFCI relied on operator judgment to control soil replacement depth. Reclamation of the remaining active RDA site involved placement of topsoil immediately following placement of suitable subsoil material. All topsoil was placed by tractor scrapers and tracked dozers from one existing stockpile and the borrow area. A road grader was utilized in some areas to insure that a uniform depth was achieved. Surveying stakes were set prior to topsoil placement on the RDA and RDA borrow area to provide depth control for equipment operators. Contemporaneous reclamation of the RDA prior to reclaiming the final active area in 2002 was accomplished initially by Dorchester Coal Co. (DCC), then by several outside contractors. DCC and these contractors utilized their individual methods and means to place topsoil on those sections of the RDA in accordance with approved requirements.