2016-01-07_GENERAL DOCUMENTS - C1981019

• Permit No: C1981019
• IBM Index Class Name: General Documents
• Doc Date: 1/7/2016
• Doc Name: Proposed Decision & Findings
• From: DRMS
• To: Colowyo Coal Company
• Permit Index Doc Type: Findings
• Media Type: D
• Archive: No

coal seams extracted from, the West Pit were the same as those of the East Pit. The West Pit was
roughly the same overall size as the East Pit. Mining in the West Pit advanced from the north to
south, paralleling the movement of the adjacent East Pit. Mining operations in the West Pit was
completed in 2015.

Colowyo is continuing to perform reclaimation activities in the East Pit and West Pit.
Reclamation in the East Pit and West Pit is expected to conclude in 2029.

Operations in the South Taylor Pit began after the approval of PR-02 in 2007. This pit is located
north and west of the northward flowing Good Spring Creek and southwest of the West Pit. It
lies partially in Rio Blanco County. In the South Taylor Pit, 17 seam and sub-seam complexes
will be mined. The seams are the A, B, C, D, E, F and G seams and their seam complexes (for
example, the G-Seam is separated into G7, G8 and G9 in the South Taylor Area). The South
Taylor Pit will be nearly 4,000 feet wide, 6,000 feet long, and 550 feet deep. Pit progression is
from southeast to northwest. Projected life of the South Taylor Pit is estimated to be until 2017,
not including potential highwall mining, which could prolong this schedule.

The East Taylor Fill is permitted for approximately 19.8 million cubic yards of permanent
excess spoil from this pit. Additionally, Colowyo has permitted the West Taylor Fill for
approximately 27.6 million cubic yards of permanent excess spoil. Two of the parcels in the SL-
08 application is a portion of the West Taylor Fill.

Reclamation in the South Taylor Pit is expected to conclude in 2029.

Permit, Performance Bond, and Bond Release History

The permanent program mining permit was issued on November 4, 1982. Six successive permit
renewals have been approved subsequent to the initial permanent program permit approval; the
most recent, Permit Renewal No. 6, was issued April 5, 2013, for a permit term that will expire
November 5, 2017. The Division currently holds a reclamation bond, in the form of two
corporate sureties, in the amount of $80,517,829.00.

Colowyo applied for seven previous bond releases: SL-01 was a Phase I/II Bond Release submitted
on 2 June 1987 and approved on 8 October 1987; SL-02 was a Phase I Bond Release submitted on
25 September 1997 and approved on 27 April 1998; SL-03 was a Phase II Bond Release submitted
on 26 September 2000 and approved on 15 August 2001; SL-04 was a Phase I/II Bond Release
submitted on 1 June 2010 and approved on 2 May 2011; SL-05 was a Phase III Bond Release
submitted on 28 June 2010 and approved on 25 July 2012; SL-06 was a Phase I Bond Release
submitted on 26 April 2012 and approved on 9 April 2013; SL-07 was a Phase I Bond Release
submitted on 2 April 2013 and approved on 29 August 2013. See Exhibit 1 in the SL-08 application
for the locations of the previous Phase I Bond Releases at the Colowyo Mine. See Table 1 in this
document for the previous bond release acreages and Table 2 in this document for the previous bond
release amounts (no amount was released with SL-02 and SL-03 as the associated monies were
“floated” to other areas of the mine where there was new disturbance).

Proposed Decision and Findings of Compliance January 2016
Partial Phase I Bond Release SL-08 Page 3