2015-10-06_PERMIT FILE - C1981019A

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 10/6/2015
• Doc Name: Operation and Reclamaiton Plans
• Section_Exhibit Name: Volume 15 Rule 2.05
• Media Type: D
• Archive: Yes

RULE 2 PERMITS
approximately 7 bcy per ton. Normal bench dimensions and heights as described in the ground control
plan will be used. Table 2.05.2 -3 presents the estimated yearly production.
The Little Collom X pit is located approximately one and one -half mile north and 600 feet lower in
elevation relative to the Collom Lite pit. Similar to the Collom Lite pit area, the area to be mined within
the Little Collom X pit covers an area of two long ridge lines at about 7000 feet in elevation which is
bisected by a 100 foot deep valley formed by the stream channel of Little Collom Gulch. Ultimately the
Little Collom X pit will cover approximately 213 acres and will be 100 feet deep in places.
Seams to be mined in the Little Collom X pit include the Y and X seams. As shown on the geologic
cross - sections presented in Figure 2.04.6 and on Map 7, the coal seams to be mined are located in the axis
of the Collom syncline with the northern portion of the pit having beds dipping approximately 3 to 10
degrees to the southwest re- orientating to flat in the axis hinge and then slightly dipping to the northeast
in the southern portion of the pit. Mining will proceed as described on Map 2313, generally in a
southward direction into the hillside along the bedding plane beneath the X coal seam.
A specific description of the initiation of mining activities in the Little Collom X Pit is described
below:
Sediment Control System Construction:
Initially, Colowyo will construct the downstream sediment control pond and the sump
near the eventual toe of the proposed temporary spoil pile in order to establish sediment
control in the area. (See drawings Exh. 7, Item 26, Figure I and Exh. 7, Item 26, Figure 2
for location and layout of the sediment control ponds.)
Little Collom X Pit and Initial Areas of Temporary Spoil Pile:
Topsoil will then be stripped from the initial X seam coal footprint, the initial Temporary
Spoil Pile footprint, and the corridor for construction of the Temporary Spoil Pile
underdrain. These areas are depicted in the upper part of Map 23B. Construction of the
Temporary Spoil Pile underdrain will commence in the valley bottom progressing
upstream from the southernmost limit of the Little Collom X Pit and progressing
downstream toward the Little Collom Sump as mined overburden from the X Pit backfrlls
the pit. This will ultimately be occupied by the northern end of the temporary spoil pile,
although the toe of the pile will not approach the Little Collom Sump until about 2015
(See profile A -A' on Map 29C). Backfilling of the X seam pit will closely follow coal
removal given the shallow nature of the pit and strip ratio of the coal. Initial construction
of the toe of the temporary spoil pile (northern extent) cannot commence until mining of
the X seam under the footprint is completed, the area is backfilled and the underdrain
constructed. Map 23B presents the anticipated timing sequence of mining progression in
the Little Collom X Pit, while Map 29B shows reclamation sequencing. Note that on
Map 29B the final reclamation of the southernmost portion of the Little Collom X pit is
not scheduled until 2033, keyed to completion of removal of the temporary spoil pile.
Exh. 7, Item 23, Fig Al shows the estimated disturbance footprint six months after start
of stripping (see tan shaded CN 85 areas). That "tan" area includes striping for Collom
X pit as well as stripping for the Temporary Spoil Pile and associated roads. Map 23B
Collom — Rule 2, Page 92 Revision Date: 9/28/11
Revision No.: PR -03