2014-10-27_INSPECTION - C1981035

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October 23, 2014 C- 1981 - 035 /King Coal Mine MLT HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5, 4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water Monitoring 4.05.13; Surface Water Monitoring 4.05.13; Drainage — Acid and Toxic Materials 4.05.8; Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18: • Culverts and ditches throughout the King II surface facilities were generally clear and in excellent condition. All drop inlets were found to be unobstructed and well maintained. • The outlet of culvert C3 (twin 24" culverts) were partially blocked with sediment, as noted in the 3rd quarter pond inspection report. Maintenance of the outlets is needed. The outlet of culvert C5B was about one -third filled with sediment, and should be cleaned. (For culvert locations, see Map King II- 007A.) • The King II sediment pond held a shallow pool of water, at an elevation well below the top of the concrete footer for the discharge structures. Both ponds at King I were holding a small amount of water; no discharge was occurring. EXCESS SPOIL and DEVELOPMENT WASTE Rule 4.09 Placement; Drainage Control; Surface Stabilization: • The King I Refuse Pile surface had a number of end - dumped piles of coal mine waste on it, awaiting placement and compaction. The majority of this material was generated over the past winter, and had been hauled uphill from its temporary storage location below. Mr. Wymore pointed out a few loads that were "fresh ". This material was rocky, or "bony'' containing less fines and less coal. For placement and compaction, these materials (older fine and newer coarse) should be mixed together to the extent possible to create a more consistent material without rocky zones, which are difficult to compact. • The footprint of the lower coal mine waste disposal area proposed for King I has been graded smooth, and trash was removed from the corner. To take advantage of the large excavator temporarily on site, a trench drain was dug along both highwalls as shown in the proposed design. • While the pad gradient is smooth, we found certain areas that may not have been firmly compacted. The entire surface should be compacted, with moisture added as necessary, then graded /trimmed smooth prior to the placement of coal mine waste. • The majority of the exposed highwall consists of competent, exposed bedrock (sandstone and shale). However, the trench along the back highwall skirts an area of unconsolidated material that has sloughed down from above (Photo 3). This loose material probably should be removed, to expose a clean surface of bedrock behind, against which to compact the coal mine waste. REVEGETATION Rule 4.15 Vegetative Cover; Timing: • A utility line corridor between the man portal and belt portal access road was seeded approximately five years ago. The grass component of the revegetation has diminished with time, but shrubs such as rubber rabbit brush appear to be lasting. No noxious weed species have become established along the corridor. Number of Partial Inspection this Fiscal Year: 4 Number of Complete Inspections this Fiscal Year: I Page 3 of 6