2010-04-13_REVISION - C1980007

• Permit No: C1980007
• IBM Index Class Name: REVISION
• Doc Date: 4/13/2010
• Doc Name: Adequacy Letter
• From: DRMS
• To: Mountain Coal Company, LLC
• Type & Sequence: TR120
• Email Name: TAK
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203 C O L O R A D O
Phone: [phone] D IVI S ION OF
RECLAMATION
FAX: [phone] MINING

April 13, 2010 SAFETY
Kathleen G. Welt Bill Ritter, Jr.
Mountain Coal Company, LLC Governor
P.O. BOX 591 James B. Martin

Somerset, CO 81434 Executive Director
Loretta E. Pirieda
Director
Re: West Elk Mine (Permit No. C-1980-007)
Technical Revision No. 120 (TR-120)
Refuse Pile Expansion East
Dear Ms. Welt:
The Division has received Mountain Coal Company's emailed responses of April 7 and April 9, 2010. The Division's
follow-up comments are provided below, using the numbering of our previous comments.
8. b) As previously requested in our letter of April 5, 2010, please add to Section 3.2 the dimensions of the manholes,
and identify the construction materials of these structures. Also, please add to Appendix 82 a cross-section drawing
showing the details of a manhole structure.
c) As previously requested in our letter of April 5, 2010, please add to Appendix F a SEDCAD run (or other similar
analyses) for the east and west clear water diversion ditches that includes runoff from the surface of the reclaimed
RPE East after final reclamation. Buried pipes are not acceptable as permanent diversions because of their
potential for failure over a long period of time. Failure may enable surface water to enter the fill and cause
structural instability. Rule 4.05.3(1)(e) requires that diversions be designed to be stable. Rule 4.05.3(1)(d)
requires diversions to be designed so that they do not endanger property or public safety. Rule 4.05.4(4)(b)
allows the use of artificial structural controls for permanent diversions only if approved by the Division. The
Division believes open channels on the surface are more likely than buried pipes to allow the drainage channel in
No Name Gulch to remain in dynamic equilibrium with the drainage basin system; therefore, the Division cannot
approve the proposal to use buried pipes as permanent diversions.
11. As previously requested in our letter of April 5, 2010, please add to Section 8.1 the following commitment: Upon
approval of the previously mentioned technical revision, the east and west sediment drainage pipes and manhole covers
will be removed, and the perimeter of the refuse pile will be re-graded so that surface drainage is routed to the 100-year
clear water ditches. Please include a description of the final configuration of the areas that will be re-graded. As
explained in our preceding comment 8c, the Division cannot approve the pipes as permanent diversions; therefore, they
will be temporary diversions. Rule 4.05.3(6) requires removal of temporary diversions. Also, in order to document that
roads will need to remain in place for completing reclamation operations, please add the words " reclamation or"
immediately before the word "other" in the first sentence of Section 8.1.3.
The Division will complete a reclamation cost estimate upon resolution of the preceding comments.
Sincerely,
kVe,
Tom Kaldenbach
Environmental Protection Specialist
cc (via email): Dan Hernandez, DRMS
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines