_INSPECTION - C1980007 ‎(26)‎

• Permit No: C1980007
• IBM Index Class Name: INSPECTION
• Doc Name: OSM Inspection Report
• From: OSM
• To: DRMS
• Inspection Date: 7/29/2009
• Email Name: TAK
• Media Type: D
• Archive: No

J
West Elk Mine Field Evaluation
Colorado Division Reclamation, Mining and Safety(CDRMS) Permit No. C-80-007
Tuesday, July 28, 2009 8:30 a.m. —4:00 p.m.
Participants:
Elizabeth Shaeffer, USDUOffice of Surface Mining(OSM)
Howard Strand, OSM
Tom Kaldenbach, Colorado Division of Reclamation, Mining, and Safety(CDRMS)
Ryan Sweetwood, Mountain Coal Company
Kathy Welt,Mountain Coal Company
Weather conditions: sunny and warm in the morning, overcast in the afternoon
The purpose of this evaluation was to gather information on subsidence related material damage
to, and of the diminution of reasonably foreseeable use of, structures and renewable resource
lands within permit and adjacent areas at the West Elk mine. As part of our oversight process,
the Colorado Team is evaluating"Prevention of Material Subsidence Damage to, and the
Diminution of Reasonably Foreseeable Use of, Structures and Renewable Resource Lands."
This site visit helped the Evaluation Team assess subsidence-related impacts and mitigation
measures for the purpose of our study, and verified whether mine operators are complying with
applicable regulatory and permit requirements pertaining to the monitoring and reporting of the
effects of underground mine subsidence.
Kathy Welt and Ryan Sweetwood provided a summary briefing of the situation at the main
office. They referenced maps and aerial photographs of the mine and explained to us that current
longwall mining operations are located in approximately the middle of Panel 1 in the E Seam,
and that the B Seam was mined from 1990 to December of 2008. Mining Seam Panels B 18,
B25, and El were evaluated in the field for this topic. There are no structures within the angle of
draw for mining operations in these panels over the last 24 months. Similarly,there are no
renewable resource lands (recharge areas for aquifers and areas that support food and fiber).
Offsite impacts from subsidence for Panel B18 would consist of cracks, slides, and rock falls.
However,none have been identified to date.
Panel B25 extends under Sylvester Gulch, whose alluvium is not an aquifer that produces water
for beneficial use. Although some rock falls have occurred, they were predicted by the mine in
accordance with their approved subsidence monitoring program. In addition, there is evidence of
rock falls from the rock face on the east edge of Panel B25. These, too, were predicted by the
mine.
The Team was also concerned about the possibility of diminishing the water in the North Fork of
the Gunnison River(i.e., stream pirating) as a result of subsidence,but none was observed.
CDRMS' primary concern is the potential for subsidence-related impacts to State Highway 133,
which runs parallel to Panel B18, since the mine facilities appear to be shifting toward the
highway at a rate of a few centimeters per year(see Figure 1). The mine has not installed long-