2010-05-12_PERMIT FILE - C1981010

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 5/12/2010
• Doc Name: Revised K-Pit Butttress Fill Stability Analysis, Feb 2010
• Section_Exhibit Name: Appendix T
• Media Type: D
• Archive: No

February 1, 2010 Page 9
Agapito Associates, Inc. (2008b), "Horse Gulch Fill Stability Analysis— Trapper Mine,
Colorado," prepared for Trapper Mining, Inc., December.
Agapito Associates, Inc. (2007), "G -Pit Landslide Stability Report—Task 2" prepared for
Trapper Mining, Inc., .March 19.
Capstone Enterprises West, LLC. (2008), "Geologic Review and Soils Engineering Report,"
prepared for Trapper Mining, Inc., June 4.
Colorado Division of Minerals and Geology (1980), Regulations of the Colorado Mined Land
Reclamation Board for Coal Mining, effective August 30, Section 4.09.1, p. 305.
Douglass, P., and M. Bailey (1983), "Evaluation of Surface Coal Mine Spoil Pile Failures,"
Third International Conference on Stability in Surface Mining, Vol. 3, pp. 815 -836.
Itasca Consulting Group, Inc. (2005), Fast Lagrangian Analysis of Continua — User's, Guide,
Minneapolis, MN, Version 5.0.
GEO -SLOPE International Ltd. (2008), Stability Modeling with SLOPE /W 2007 —An
Engineering Methodology, 4 "' Edition, November, Calgary, Canada, 355 p.
Rocscience Inc. (2009), RocLab v.:1.0, free download from <http: / /www.rocscience.com/
products/Roc Lab. asp >.
Agapito Associates, Inc.