2015-10-13_REVISION - C1981014 (7)

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SOUTHFIELD MINE PHASE II BOND RELEASE LOADOUT AREA 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 Loadout area was reclaimed during 1996 in accordance with the approved reclamation plan. The entire site was backfilled and graded with the exception of the two sediment ponds. Topsoil from the two existing topsoil piles was then distributed over the entire area. Permit application Section 2.05.4, Redistribution of Topsoil, addresses topsoil sources, replacement methodology, replacement thickness, and fertility sampling at the Loadout Area. The permit required that approximately 6 inches of topsoil be placed on regraded areas from the two existing topsoil piles. Topsoil was placed on regraded areas that were intentionally left in a roughened condition after backfilling and grading operations. All available topsoil was placed by tractor scrapers and tracked dozers from the stockpiles. 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. TOPSOIL THICKNESS AND FERTILITY TESTING AND RESULTS Topsoil thickness was monitored during placement activities described above. Thickness depth and fertility testing were spot checked in 2015. A summary of the measurement results are shown on Table 1. Test locations are shown on the accompanying map "Topsoil Test Sites - Loadout Area". Loadout area topsoil thickness measurements taken in 2015 indicate an average topsoil thickness of 5.1 inches. The topsoil at the time of testing has compacted over time, and is generally representative of the approximately 6 inches of topsoil placed in 1996. EFCI sampled and completed laboratory analyses from topsoil sampled at the test sites shown on Table 1, and a summary of the laboratory data is shown on Table 2. Topsoil fertility test results do not indicate any deficiencies in critical soil nutrients or any potential salinity problems that could limit vegetative establishment. Vegetation establishment has in fact been successful as demonstrated in the 2013 and 2014 vegetation sampling results included with this application.