REP05084

• Permit No: C1981044
• IBM Index Class Name: Report
• Doc Date: 3/5/1997
• Doc Name: 1996 SEMI ANNUAL SUBSIDENCE MONITORING REPORTS CYPRUS EMPIRE CORP EAGLE MINE 5 JAN-DEC 1996 C-81-044
• From: DMG
• To: BYRON WALKER
• Permit Index Doc Type: SUBSIDENCE REPORT
• Media Type: D
• Archive: No

lIII IIIIIIIIIIIIIIII
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Department of Nawral Resources
I31 3 Sherman 51., Room 21 S
Denver, CnloraAo 80203
Phone: [phone]
FAX: 13031 R32-8106
DATE: March 5, 1997
TO: Byron walker
FROM: Jim Pendleton
,~Y/~
~~
DEPARTMEMC OF
NATURAL
RESOURCES
Roy Romer
Governor
lames 5. Lochhead
Executive D~reclor
Michael 8. Long
Division Uireaor
RE: "1996 Semi-P~,rt~iual ~bsidence Monitoring Reports
Cyprus Em ire rporation, Eagle Mine No. 5
January - December 1996" (Permit No. C-81-044)
I have reviewed the above referenced annual subsidence monitoring data
summary reports, submitted by Cyprus Empire Corp. for their Eagle mine.
The data presentation is clear and well formatted. The color map is also
helpful and very easily read. I have also read your draft adequacy
letter, as you requested.
As you are probably aware, from examining the Eagle Mine file, I have been
involved sporadically with their subsidence monitoring requests over the
past 18 years. In general, they have compiled one of the most
comprehensive subsidence monitoring data bases in Colorado. In fact, they
have collected considerably more engineering-related subsidence data than
they are obliged to submit by their permit. Cyprus Energy's corporate
philosophy zealously guards this data. They only share it with us if
necessary to resolve a dispute, and then they usually demand it be kept
confidential. Their corporate policy also abhors blithely conceding to
any regulatory request.
In the event that you may not be aware, Monitoring Points N-1, N-2 and N-3
can be found on Permit Application Map #31, "Subsidence Monitoring". They
were incorporated in monument lines "K" and "R", whose monitoring
cessation was previously approved.
Because the multiple seam extraction beneath monument lines A, B, C, D and
S have been extracted for some time, I see no reason not to approve
cessation of monitoring of these monument sets. I would, however, require
CEC to maintain the monuments so that they could be resurveyed in the
event that any concern were to develop regarding subsidence of those
areas. Finally, we may want to require them to survey them as a condition
of final liability release for these permit areas.
In regards to CEC's request to cease monitoring monument line J and
monument sets H and N temporarily, until recommencement of mining, I would