REV93319

• Permit No: C1981033
• IBM Index Class Name: Revision
• Doc Date: 11/7/1994
• Doc Name: TR SUBSIDENCE MONITORING BEAR COAL CO PN C-81-033
• From: DMG
• To: TONY WALDRON
• Type & Sequence: TR20
• Media Type: D
• Archive: No

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STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Depanment of Nawral Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
fA%: X3031 8328106
Date: November 7, 1994
To: Tony Waldron
From: David Berry
Re: Technical Revision/Subsidence Monitoring
Bear Coal Company, Permit No. C-81-033
~~~~~
DEPARTMENT OF
NATURAL
RESOURCES
Roy Romer
Governor
dames S. Lochhead
E*ecutive Director
Michael 8. Long
Division Dvecror
I have reviewed the technical revision package submitted by Bear Coal Company, received
August 29, 1994. I have also reviewed the staff memoranda from Kent Gorham (dated
October 19, 1994) and from Jim Pendleton (dated October 18, 1994). As a result of my review,
I have some concerns which appear to be similar to the concerns voiced by Kent. Today, I spoke
with Jim Pendleton about the conflicting views, since Jim has been involved with all subsidence
and landslide-related matters in the North Fork of the Gunnison River since original permitting of
the local mines.
As I understand it, Jim is fairly confident that mobilization of the large landslide(s) adjacent to
the Bear Mine is not likely. However, it must be noted that there has been considerable surface
slide activity in the general area near the mine during spring of 1993.
Jim has now recommended that if all monitoring is to be eliminated as proposed in the most
recent technical revision, then a definitive study must be conducted by an expert in the field of
mass wasting, relative to Bear Mine subsidence impacts. Jim recommends John Ivy or Michael
Bukovanski.
It may also be premature to assess this proposal, given the ongoing permit revision application
for the Bear Mine. The proposal should be denied at this time, for the specific reasons outlined
below. Reconsideration can be allowed as also discussed below.
1. Station UAl Must continue monitoring since additional mining impacts are projected. It is
interesting to note that the largest vertical movement in this station seems to
correspond with the recent period of slide activity in the spring of 1993.
Station Ll'I2 This station may not have stabilized. Continue monitoring. Vertical move-
ment possibly corresponds with the spring 1993 slide activity.
Station Ul Additional mining impacts are anticipated. Vertical movement may
correspond with spring 1993 slide activity. Keep monitoring.