2020-12-11_GENERAL DOCUMENTS - C1981010

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The approved postmining land use for the land applicable to SL21 is rangeland/wildlife habitat and the 298.3 acre bond release block is being reclaimed as such. The backfilling and grading plan is designed to achieve the approved postmining land use. After final backfilling and grading, topsoil is required to be placed on the spoil to a depth of 18 inches on cropland and 12 inches on rangeland. A variation of +/- 2 inches is allowed due to compaction and operational considerations as per TMI's permit(page 4-256). Trapper constructs drainages on newly deposited spoil, consisting of relatively unconsolidated rock and soil comprised of the overburden material removed in the mining process in accessing the coal seam. Channels are seeded, achieving a grass lined channel within approximately two years. When the majority of the watershed is at two years or more of vegetative growth,the grass lined channel is generally stable without requiring armoring. IV. OBSERVATIONS AND FINDINGS Reclamation, comprised of backfilling and grading, topsoil placement and seeding for the requested Phase I SL21 reclamation parcels,occurred between 2017 and 2019. TMI verifies topsoil replacement thickness by scraper load counts. TMI included a load count for reclamation parcels in the bond release application as well as topsoil depth verification. Although not required for Phase I bond release, DRMS frequently conducts topsoil replacement depth verification during monthly inspections as documented in DRMS inspection reports. Constructed drainage do not require topsoil. The Division confirms that reclamation parcels have been backfilled and graded in accordance with the approved postmining topography and that drainage control has been accomplished. The Division in October 2017, September 2018, and in September and October of 2019, measured topsoil depths on the parcels associated with this bond release and found that topsoil replacement occurred in accordance with the approved reclamation plan. Documentation of DRMS measurements can be found in the associated inspection reports. Compliance with Approved Post Mining Topography The Division evaluated the reclamation parcels to determine if the affected areas have been backfilled and graded in accordance with the approved post mine topography. To evaluate the SL21 bond release block for Phase I bond release, the Division compared the approved post mining topography (PMT) as depicted on Map M12 in the permit application package with the Annual Reclamation Report Maps (ARR Map M1, approved by the Division November 2020 and integrated into the permit at that time as the defacto on the ground topography) and the actual on the ground conditions after backfilling and grading that occurred as represented by the SL21 bond release maps (M1). Reclaimed topography is reported each year with TMI's annual reclamation report maps reviewed and approved by the Division. Prior to the field inspection, DRMS performed a map evaluation on parcels ZA17 and LA18 of submitted reclamation topography utilizing Map M12,Post Mining Topography (current PMT map), and M1(SL21 submittal). During the Phase I field Permit Number C1981010 Prepared by: R.Reilley,MS,GISP SL21 Page 9 of 15