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The location and configuration of the proposed activities are shown on Figure 49W -F1, WMD Stabilization <br />Boreholes. <br />isfoot drainage control and sediment control measures for these activities include placement of a 36 -inch x 80 <br />foot CMP culvert in the borrow ditch for County Road 27 to allow road runoff to pass under the temporary access <br />road (culvert is sized to match the existing downgradient culvert crossing under the road), construction of a <br />temporary diversion ditch and catch basins upgradient of the drill pad to intercept and route any natural runoff <br />around the pad, and placement of straw wattles downgradient of the pad to intercept and control any runoff that <br />escapes the pad. Temporary drainage and sediment control measures will be in -place before any other activities <br />proceed. <br />Available soil materials will be recovered from both the short access road segment and the pad area and placed in a <br />temporary stockpile upgradient of the pad. With a road area of approximately 40 x 240 feet, a pad area of <br />approximately 200 x 300 feet, and an average soil recovery depth of approximately 1 -foot, approximately 2,600 bcy <br />of soil material will be recovered and stockpiled. Pad construction will involve cut and fill grading of the pad area <br />to establish a level surface approximately 200 x 300 feet. A temporary cuttings pit, with a capacity of <br />approximately 60 cy, will be excavated during pad construction, and the excavated material will be incorporated <br />into the cut /fill balance. The pad will be constructed so that surface runoff from the pad area will be retained on the <br />pad (ie: the pad surface will be sloped to drain to the cuttings pit). <br />Two boreholes, approximately 13- inches in diameter and 1,425 feet in depth will be drilled from the pad to <br />intercept the 17 -Left gate -road. During drilling operations, any excess cuttings will be removed from the cuttings <br />pit and trucked off -site by a qualified contractor, in order to maintain adequate buffer capacity in the pit and avoid <br />any discharge. The boreholes will be cased with up to 8- 5/8 inch steel casing and the casing will be grouted in the <br />hole. A temporary concrete batch plant will be set -up on the existing 18 -Left Shaft Pad, and a temporary concrete <br />transfer line will be laid on the ground surface between the batch -plant and the boreholes. Concrete will be pumped <br />through the transfer line and down the boreholes into the 17 -Left gate -road, where it will be transferred through an <br />underground line to the area of instability to establish supplemental support pillars. <br />• Once concrete pumping operations are completed, the temporary transfer line and batchplant will be moved off -site, <br />and the boreholes and associated disturbance areas will be reclaimed. Boreholes will be plugged and sealed in <br />accordance with applicable State Engineer requirements. Any residual cuttings in the cuttings pit will be allowed to <br />dry -out, and the cuttings pit will be completely backfilled. The pad area and road will be regraded to their <br />approximate original configuration and to blend with the surrounding terrain, the temporary diversion ditch will be <br />removed, stockpiled soil material will be replaced, and all disturbance areas will be reseeded with TC's standard <br />Pastureland Seed Mixture, or an alternate seed mix, if requested by the surface landowner. <br />16 -Left Utility Borehole (TR11 -78) <br />TC proposes to complete a new utility borehole, to be located over the 16 -Left (16LT) gateroads in the Western <br />Mining District (WMD). The utility borehole will initially serve as a conduit to transfer concrete from the surface <br />to the underground workings to provide supplemental support for an area where elevated geologic stresses were <br />encountered in the previous longwall panel. Subsequent to this initial use, it is anticipated that the borehole will be <br />retained and utilized as a supplemental utility borehole for transfer of concrete, gravel, or other materials to the <br />underground workings for use in the WMD. The proposed facilities will be accessed from the paved County Road <br />(RCR27), using the existing access for the 17 -Left Concrete Borehole (MR11 -253), with a new light -use road to the <br />borehole pad location, as shown on Map 24 (4/4) and Figure 49Z -F 1. <br />The proposed utility borehole installation will require construction of approximately 1.25 mile of new light -use <br />road from the existing 17LT access point to the borehole pad location, and construction of a new borehole pad <br />(approximately 200 x 300 ft.). The 16LT Utility Borehole installation will consist of the new light -use road and <br />borehole pad; adjacent soil material stockpiles, and the lined and grouted borehole extending into the active mine <br />•workings. The road disturbance corridor will be 40 feet wide, although the actual road surface will only be <br />approximately 24 feet wide. The total road disturbance area will be approximately 6.1 acres, and the pad <br />disturbance area (includes cut /fill slopes and soil stockpiles) will be approximately 2.2 acres. <br />TR11 -78 2.05-45.21 09/15/11 <br />