2011-12-30_REVISION - C1994082

• Permit No: C1994082
• IBM Index Class Name: REVISION
• Doc Date: 12/30/2011
• Doc Name: Review Letter
• From: DRMS
• To: Seneca Coal Company
• Type & Sequence: TR51
• Email Name: SLB
• Email Name: SB1
• Media Type: D
• Archive: No

DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
December 30, 2011
Mr. Roy Karo
Seneca Coal Company
P.O. Box 670
Hayden, Colorado 81639
Re: Yoast Mine (Permit No. C- 1994 -082)
Technical Revision No. 51 (TR -51)
Landslide/Instability Identification/Remediation Plans
Dear Mr. Karo:
Office of
Mined Land Reclamation
STATE OF COLORADO
COLORADO
D I V I S I O N OF
RECLAMATION
MINING
—&—
SAFETY
John W. Hickenlooper
Governor
Mike King
Executive Director
Loretta E. Pineda
Director
The Division has reviewed your application for TR -51 to the Yoast Mine permit (Permit No. C-
1994 -082), and we do not have any adequacy concerns with the revision as proposed. Once the
Division has received proof of the publication required by Rule 2.08.4(6)(b)(i), we will propose a
decision to approve the revision.
The Division also asked the Colorado Geological Survey (CGS) to review the revision materials.
CGS notes that the various proposals described in TR -51 (with the exception of the Pond 012 slide)
are improvements to drainage and/or revegetation for short term stability, and cautions that
quantitative geotechnical investigations or analyses would be necessary to better determine long
term stability. CGS recommends visual observation of the slide areas. Should there be major
instability in the future, a detailed geotechnical investigation may be warranted. I have enclosed a
copy of Jill Carlson's (CGS) memo.
The Division also received comments on the proposal from the Bureau of Land Management
(BLM). A copy of those comments is enclosed.
The Pond 013 and Neck Pit slides are within areas previously Phase I bond released. The current
instability of these areas will necessitate rescission of the Division's Phase I bond release approval.
Accordingly, the Division will initiate a surety increase action (SI -1), as provided by Rule 3.02.2(4),
to require SCC to resume reclamation liability on those areas. The notification for SI -1 as required
by Rule 3.02.2(4)(a) will be forthcoming.
The remaining areas of minor instability previously identified by the Division and not specifically
addressed in this revision application (settlement cracks along highwalls) will be further monitored
Office of
Denver • Grand Junction • Durango Active and Inactive Mines