2014-10-15_PERMIT FILE - C1982056A ‎(7)‎

• Permit No: C1982056A
• IBM Index Class Name: Permit File
• Doc Date: 10/15/2014
• Doc Name: Pages 2.05-65 to 2.05-197.3 part 2
• Section_Exhibit Name: 2.05 Operation and Reclamation Plans Part 2
• Media Type: D
• Archive: Yes

NMD (Panels 12 -Right through 16- Ri2ht, PR 99 -05
The geology description provided in PR -03 is also applicable for the NMD. One item to note is that TCC
discontinued pumping from the Fish Creek Borehole for a period of approximately 18 months. When pumping
recommenced the total recoverable iron and total dissolved solids concentrations increased to approximately 17
mg /l and 7,200 mg /l respectively. TCC is applying caustic soda to reduce the total recoverable iron concentration
as per its CDPHE discharge permit. TCC believes the elevated concentrations are the results of the water
stagnating in the underground sump. Once this pool of water is discharged, TCC believes the concentration will
return to levels previously reported for the Fish Creek Borehole. TCC will continue to monitor the concentration,
and anticipates the concentration to return to historic levels by late summer, 2000 or 2001.
In regards to future impacts, TCC will not discontinue pumping of the underground sump for extended periods of
time. This will eliminate the potential for the above situation to occur in the future. Once mining is completed at
the facility, no further discharging will occur. Based upon this, there should be no impact to the postmining land
use.
Coal Refuse Disposal Area (CRDA TR92 -15 TR95 -21 MR08 233 TR09 67)
The original Coal Refuse Disposal Area (CRDA), located to the southwest of the Area 1 Pit, as shown on Map 24,
Surface Facilities, has been designed to hold approximately 3,000,000 cubic yards of material. The CRDA is
designed to accommodate temporary placement and permanent disposal of coal refuse materials generated from the
preparation plant, excess coal development waste material from the mine, or a combination of preparation. plant and
mine waste material. This material or combination of materials will be hauled to the pile using either TCC's
existing mobile equipment fleet or contractor equipment. The original design of the CRDA was contracted to
CTL /Thompson. The design was revised and updated to reduce the overall footprint and address operational
placement and final grading concerns, by Northwest Colorado Consultants. Both the original design and revisions
are documented in Exhibits 26A, 26A -1, and 26A -2. Within 30 days of start-up of the preparation plant, a sample
of the waste material generated from the preparation plant was obtained and analyzed to verify the assumptions
used for the pile design presented in Exhibit 26A. TCC forwarded results of this analysis to the Division along with
a certified statement from a registered P.E. summarizing the results of the analyses as compared to the original
design assumptions. The surface runoff/diversion system design for the pile was developed in -house by TCC and is
presented as Appendix D to the CTL /Thompson Report. The locations of the CRDA and associated drainage
features are shown on Map 24, Surface Facilities.
As shown on Exhibit 26A, Figure 1, the CRDA is constructed west of the reclaimed valley to the west of the Area 1
Pit. Prior to construction, approximately 18 inches of topsoil from within the pile footprint were removed and
placed in topsoil stockpile SF -12 (see Map 29). During reclamation of completed pile benches, suitable cover
materials and topsoil will be redistributed over the face of the pile. Direct placement of topsoil will occur to the
extent possible during the bench reclamation/pile extension process. It is anticipated that topsoil replacement will
stay one bench below the active working zone of the pile. During construction of the CRDA, inactive portions of
topsoil stockpile SF -12 will be seeded with the topsoil stabilization seed mixture at the first appropriate opportunity
following stockpiling operations. Table 49A, Topsoil Stockpile Summary, has been revised to show the potential
modification to the existing stockpile SF -12 resulting from the construction of the refuse pile. Also, the table
presents information for all other Twentymile topsoil stockpiles. The stockpile identification numbers in the table
correlate with the stockpile designations presented on Map 29.
Spoil/subsoil material will be used as suitable, non -toxic cover, to be placed over completed refuse benches prior to
topsoil replacement. During development of the refuse pile, spoil /subsoil material will be selectively removed from
within the footprint of the pile. The spoil/subsoil will normally be hauled directly to an active reclamation area and
spread over the completed refuse bench. In cases where direct placement is not operationally feasible, cover
materials may be temporarily stockpiled within the pile footprint or in adjacent areas. After placement of the
spoil /subsoil material, the area will be topsoiled, as previously described. Redistributed topsoil will be seeded with
the pastureland seed mixture.
TR09 -67 2.05 -96 06/16/09