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When the Barricade ChamberlFCM-2 facilities are no longer needed to support ongoing or future mining operations,
<br />the shaft and borehole will be plugged and sealed, the shaft collar and borehole casing will be demolished or cut-off a
<br />minimum of three feet below the ground surface, the hole locations will be marked, remaining foundations will be
<br />removed, and the disturbed areas will be regraded to blend with the surrounding terrain, stockpiled topsoil will be
<br />replaced, and the areas will be reseeded. It is anticipated that when the pipeline is no longer needed to support
<br />mining and related operations, it will be plugged below grade and abandoned in-place.
<br />IORT Dewaterin~ Wells (Eastern Mining District
<br />The l ORT dewatering system (original) consists of two primary components: 1) Dewatering wells and control
<br />building (existing), and 2) Treatment facility (future). The initial dewatering well was drilled to connect into the
<br />sump developed off the 10-Right entry. Please refer to Map 23, Mine Plan, for the location of the sump. A light-
<br />duty road was constructed to the site, beginning at the proposed treatment facility and terminating at the borehole.
<br />The beginning 1,600 feet of this road required new construction, while the remainder of the road involved
<br />upgrading an existing ranch road. The location of the access road is shown on Maps 17 and 18. As shown on the
<br />maps, the overall road length is approximately 4,600 feet. This location of the initial 1,600 feet of the road differs
<br />slightly from the original proposal to improve visibility and safety at the road entrance.
<br />During construction of the road, approximately 6,815 CY of topsoil was windrowed to the side of the road. This
<br />volume is based on constructing a road 4,600 feet long, 20 feet wide and salvaging topsoil to a depth of 24 inches.
<br />The topsoil was stockpiled adjacent to or windrowed to the side of the road. The stockpiled topsoil was seeded
<br />with the pastureland seed mixture applied at the appropriate rate. The finished width of the road is approximately
<br />12 feet and it is covered with approximately 9 to 12 inches of 6-inch pit run and 3 to 4 inches of 1'/s-inch road base
<br />or crushed rock. Based on use and regulatory definitions, the initial 700 feet of the road is an access road, and the
<br />remaining 3,900 feet of road is a light-duty road. Culverts were installed in the small ephemeral drainages along
<br />the road, where needed. The design calculations for these culverts, numbered EMD-1 through EMD-4, are
<br />presented in Exhibit 8A, Culvert Sizing -EMD Dewatering Facility Access Road.
<br />While permitted for installation of a water treatment facility (see the following text), the only facilities currently
<br />existing (2008) are the TORT Dewatering Well installation, powerline, discharge line, and associated light-use road.
<br />Reclamation will involve culvert removal and ripping, grading, soil replacement, and revegetation of the borehole
<br />pad disturbance and road.
<br />As constructed, the dewatering borehole installation consists of the drill-pad a 14-inch cased borehole, pump and
<br />control building, and transformer. The original drill pad was approximately 100 x 200 feet, within which two 10 x
<br />10 x 50 foot mud pits were excavated. A 17.5-inch nominal diameter borehole was drilled into the sump area,
<br />approximately 1,350 feet of 14-inch metal casing was installed in the borehole, and the annular space grouted. On
<br />completion of drilling, the mud pits were backfilled with the excavated material. A submersible purrip capable of
<br />pumping 600 gpm was installed in the casing. To complete the well installation, an 8-foot length of 8-foot diameter
<br />corrugated metal pipe with lid was installed over the cased borehole. The material excavated for the 8-foot
<br />diameter cap was spread over the pad. The control building is approximately 10 x 10 x 10 feet, and sets on a
<br />concrete pad 10 x 10 x 0.5 foot thick. A transformer was installed at the site to provide the required power for the
<br />pump. The transformer area is fenced with a 7-foot high security chain-link fence around its perimeter. A
<br />powerline, approximately 1.5 miles in length, was constructed to tie this location into TCC's power system.
<br />A 6-inch riser pipe from the pump exits the 14-inch casing, and a 90-degree elbow and associated valuing are
<br />attached for directing the discharge to the lORT/FCM-2 Transfer Pipeline or (future) into the 8-inch I-IPDE line
<br />going to the settling ponds. HDPE pipe is extremely flexible. With a cold bend radius 160 inches, the pipe can be
<br />offset 80 inches vertically over a length of 160 inches. This greatly exceeds any potential offset due to surface
<br />subsidence. Any future piping to the ponds (approximately 4,800 feet) will be buried to minirruze freezing
<br />problems.
<br />MR08-230 2.05-50.4 11/20/08
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