2008-01-11_PERMIT FILE - C1982056A (2)

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• Replace the initial segment of the existing Overland Conveyor with an inclined Crushing/Screening Feed Conveyor, and shift the Overland Conveyor tailpiece to the west • • Construct a new coal Crushing/Screening Building and install related equipment and control systems • Erect atwo-flight Washplant Feed Conveyor and Transfer Tower to transfer the intermediate coal product from the bottom of the Crushing/Screening Building to the top of the new Washplant Building • Construct Washplant II Building and install 1,300 tph washing, screening, and heavy-media and dewatering cyclone circuits • Construct a new Thickener, Thickener Underflow Line connecting to the drop-borehole into the mine, and excavate a new Thickener Overflow Sump_ ~ «°~-~ ~-~i5-~ ~-r ? • Construct the MCC/Office Building for the Washplant II complex • Erect a new Refuse Conveyor and Refuse Loading Bin • Construct a new Sampling Station on the overland conveyor • Extend a 69KV distribution line from the existing 69KV powerline, and establish a new Washplant Substation Although not specifically a component of the Washplant II project, the Stacking Tube and associated conveyor structures on the Truck Loadout pad were dismantled/demolished, and the conveyor components salvaged for reuse. The following modifications to the existing coal-handling system were made in order to integrate the new Washplant: • Continuous readings from an ash analyzer on the main underground production coal conveyor detemune whether the production flow on the slope conveyor is routed to the Run-of--Mine (ROM) Coal Stockpile or the Low-Quality Coal Stockpile by the flop-gate at the dischazge of the slope conveyor. Since the new Washplant is designed to process a significant portion of the ROM coal flow, the ash cut-off threshold for designation as low-quality coal was increased. This change results in an increase in the percentage of coal routed to the ROM Stockpile and a reduction in percentage to the Low-Quality Coal Stockpile. • • The coal-handling system for the low-quality coal was simplified to eliminate the flex-tooth crusher, one intermediate conveyor, and the two associated transfer points • The tailpiece for the existing Overland Conveyor was moved to the west and the belt shortened by approximately 700 feet to accommodate the elevated belt from the ROM Stockpile reclaim system to the top of the new Screening/Crushing Building. Belt speed was increased to accommodate a feed rate of 2,200 tph (12.OMM tpy) • The thickener overflow sump for Washplant I was eliminated and replaced with piping to carry thickener '~ overflow to the larger overflow sump constmcted for Washplant II • The primary and secondary crushers, and stoker coal and coal sampling systems in the BOB area were removed and the associated chute-work modified to allow direct pass-through of the product coal stream, since screening, crushing, and sampling will now occur in the Washplant II area. The associated Primary Crusher, Secondary Crusher, and Sampling buildings were retained, along with utilities and dust-control equipment to address potential air emissions from coal-handling and transfer points. The following sections describe the construction and operation of the various components of the new Washplant Il complex. Facility locations, configuration, and operating relationships are shown by the Freshwater Systems and Surface facilities Map, Map 24 (Sheet 1/3), and the design drawings and process flow diagrams included in Exhibit 49K, Washplant II Design Drawings. „The entire Washplant II area was disturbed by soil pre-strip activities associated with the previous surface mining activities, therefore, no soil material remained in this area. Drainage from and through this area is controlled by the existing Sedimentation Ponds D and E. Due to changes in site topography resulting from construction grading activities, the following drainage modifications were necessary: r1 LJ TR07-60 2.05-32.1 05/01/07