REV88232

• Permit No: C1980007
• IBM Index Class Name: Revision
• Doc Date: 3/18/2005
• Doc Name: Response to the Divisions 2nd Adequacy Review of 3/1/05
• From: Mountain Coal Company, LLC
• To: DMG
• Type & Sequence: PR11
• Media Type: D
• Archive: No

Permit Revision Noll
Response to CDMG Adequacy Comments, March 1$ 2005
Rule 2.04.12
3. Response accepted.
Rule 2.05.3 (3) (C) (v) (A)
4. Response accepted.
Rule 2.05.6 (6)
Page 2
5. Original Comment: Pane118A undermines an area where the state highway lies on the
same side of the river (south side of the North Fork of the Gunnison). Please discuss in the
subsidence evaluation the proximity of the slopes overlying Pane118A to the highway and
evaluate potential hazards. Please discuss any actions planned by MCC to mitigate
potential hazards.
MCC's response: Comment No. 5 concerns the presence of State Highway 133 on
the south side of the North ForkGunnison River in the vicinity of longwall panel 18A.
While the highway is only south of the river near the northwest corner of panel 18A
prior to crossing back to the north side, Wright Water Engineers (WWE) addressed
the probable impacts to the documented landslides in a recent report. In the 2004
Subsidence Report, Subsidence and Geologic Field Observations, Apache Rocks and Box
Canyon Mining Areas, July12-I5, 2004, Rich Dunrud included the following paragraph
under the heading of Analysis of the Effects of Longwall Mining on Landslides:
Based on this historic information, no effects on the landslides located south of the
North Fork of the Gunnison River (the Highway 1331andslides), are expected if
longwall mining panels 18, 18A, and 19 are mined in times of normal precipitation.
Should these longwall panels be mined during a very wet period, renewed
landslide activity could occur. However, based on the observation that very little, if
any, effects were observed on landslides on Jumbo Mountain during the mining of
longwall panels 8 and 9, any renewed landslide activity would be primarily due to
natural mass-gravity movements.
Unfortunately, this paragraph did not appear in Exhibit 60C, Subsidence Evaluation
and 2004 Geologic Hazard Field Observations West Flatiron Lease Area. WWE has
recommended referencing the 2004 Subsidence Report and adding the paragraph to
Exhibit 60C in response to CDMG's comment No. 5. MCC will request that WWE add
the paragraph to Exhibit 60C.
New Comment: The Division requests that MCC add information to satisfy Rule 2.05.6 (6).
The discussion in the PAP should include all those items presented in the appropriate Rules,
to include but not limited to the following discussion:
(a) a description of the worst possible consequences which subsidence, if it occurred,
could have on man-made structures within the permit and adjacent areas
[2.05.6(6)(a) and (b)];
(b) description of a monitoring program [2.05.6(6)(c)];
(c) an evaluation of possible material damage [2.05.6(6)(e)(ii), (iii) and (iv); and