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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 <br />bcy of soil material will be recovered and stockpiled. Pad construction will involve cut and fill grading of the pad <br />area 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 <br />the 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 gateroad. 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 batchplant and the boreholes. Concrete will be pumped <br />through the transfer line and down the boreholes into the 17-Left gateroad, 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- <br />site, 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 <br />to 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 />MRl 1-253 2.05-45.21 04/18/11