2018-01-03_REVISION - C1994082 (29)

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All exploration, drill or boreholes, wells, or other underground openings except those used solely for surface blasting will be plugged or sealed to prevent acid or toxic drainage from entering the groundwater, minimize disturbance to the prevailing hydrologic balance, and ensure safety. Details of the sealing plan are located in Tab 18 of the permit application package. No variance from regulatory requirements regarding sealing has been requested or proposed for approval, and so no specific findings apply. VI. Use of Explosives Blasting will not occur during the 2015-2020 permit term, as all mining has ceased. Explosives were previously used to fragment overburden and exposed coal at the Yoast Mine. Seneca Property, LLC typically used ammonium nitrate and fuel oil (ANFO) for this purpose, primed with cast primers and detonated with detonating cord. A certified blaster was required to be in charge of all blasting operations to ensure compliance with state and federal laws. Additional information regarding blasting operations is located in Tab 14 of the permit application package. VII. Backfilling and Grading Previously approved backfilling and grading plans ensured that disturbed areas were returned to approximate original contour in a timely manner. Findings from the three Phase I bond release approvals indicate that Seneca Property, LLC succeeded in implementing the approved plan. Details of the backfilling and grading plan, schedule, and post -mine topography are located in Tabs 19 and 20 of the permit application package. Seneca Property, LLC previously generated a topographic map, using photogrammetric methods, of backfilled and regraded areas on an annual basis. The map was used to determine whether regraded areas are consistent with the approved post mining topography. The map had been submitted to the Division in the Annual Reclamation Report each year up to 2012 when all backfilling and regrading activities had ceased. The following findings were made regarding backfilling and grading practices at the mine: The applicant requested additional time for backfilling and grading following coal removal in an area strip mine. A detailed written analysis under 2.05.4(2)(c) demonstrated that additional time was necessary to accommodate highwall mining and coal haulage access. Therefore, the Division approved backfilling and grading beyond 180 days following coal removal for select areas of final dragline pits in existing mining areas. The variance areas described below are depicted on Exhibit 19-1A, Backfilling and Grading Plan. Lower Neck Pit - Approximately 1,200 ft. of pit backfilling and grading was completed in 2004 in accordance with the approved variance schedule. North Valora Pit (directly east of Pond 012) — The lower 1,800 feet was final graded and 27