REP32950

• Permit No: C1982056
• IBM Index Class Name: Report
• Doc Date: 8/26/1985
• Doc Name: SUBSIDENCE SURVEY REPORT REQUEST FOR MONITORING REDUCTION
• From: MLRD
• To: TWENTYMILE COAL CO
• Permit Index Doc Type: SUBSIDENCE REPORT
• Media Type: D
• Archive: No

•
DEPARTMENT OF NATURAL RESOURCES
David H. Getches. Executive Director
i
MINED LAND RECLAMATION DIVISION
DAVID C. SHELTDN, Director
Richard D. Lamm
Governor
MEMORANDUM
August 1985
T0: Dan Mathews ~
FROM: Jim Pendleton
RE: Foidel Cree ine
Inc h
mit C-82-056) - Semi-annual Subsdience Report
Request for Reduction of Frequency
Pursuant to your request, I have completed a review of the monitoring report
submitted by Twentymile Coal Company for its Foidel Creek underground coal
mine. The operator is required to submit monitoring data semi-annually to
verify the effects of subsidence upon Foidel Creek and its adjoining alluvial
aquifer, and to verify the slope stability of the spoils slope opposite the
portal installation. The semi-annual monitoring data continues to demonstrate
that no measurable subsidence has been detected adjoining Foidel Creek and
that the spoils slope opposite the portals remains stable.
In addition, the operator requests that the requirement for both the Foidel
Creek subsidence and spoil slope stability monitoring be reduced in frequency
from semi-annually to annually. While I agree that no subsidence or slope
instability has been detected to date, I do not feel that it would be
appropriate to reduce the required monitoring frequency at this time. Because
of the critical consequences of either occurrence, and the relatively minor
manpower requirements to complete the semi-annual monitoring, I believe it
appropriate to continue semi-annual monitoring of both the three Foidel Creek
subsidence monuments and the three spoil slope stability monuments.
Twentymile Coal Company may resubmit their request for consideration in the
future. I don't believe it appropriate to be reducing monitoring requirements
prior to completion of the mid-term review.
cc: Bob Liddle
423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203 Tel. [phone]