2020-08-21_REVISION - C1994082 (36)

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Exhibit 12-1. Five topsoil stockpiles remain, with a total combined volume of 70.5 acre feet. Stockpiles were seeded following construction, to protect the topsoil from erosion; the remaining five stockpiles are marked with identification signs. Topsoil was not salvaged from approximately 69 of the 989.6 affected acres at the Yoast Mine. Topsoil was not salvaged from these areas because: 1. steep slopes made salvage operations unsafe 2. rock outcrops or unsuitably high clay content precluded use of the material, and/or 3. the area was been disturbed prior to mining or was under water. Soil salvage operations were monitored by Seneca Property in the field to verify removal of all available topsoil. Replaced topsoil thickness was verified by sampling reclaimed areas prior to seeding with at least one hole per five acres. Results of this sampling are documented in the Annual Reclamation Reports submitted to the Division each year. Regraded pit areas were covered with an average of 1.8 feet, and a minimum of 1.0 foot, of topsoil. Areas where shrub or tree islands were to be established were to be covered with 0.5 feet of topsoil. The facilities areas, where subsoils will not be disturbed, were to be covered with an average of 1.1 feet, and a minimum oft 5 feet of topsoil. No topsoil substitute materials are proposed for use in the Yoast reclamation plan. Reclaimed areas will continue to be monitored annually for the presence of rills and gullies. The location of these erosional features will be indicated on a map, and a report will be generated to describe the features noted and any necessary mitigation. A copy of the map and report will be submitted to the Division for its review. Details regarding the rill and gully survey and reporting are located in Tab 22 of the permit application package. V. Sealing of Drilled Holes and Underground Openings 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 historically 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 four 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 21