2010-06-28_REVISION - C1981019 (3)

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1.0 INTRODUCTION Cedar Creek Associates, Inc. (Cedar Creek) was contracted in 2007 by Colowyo Coal Company (Colowyo) to evaluate revegetated units for Phase III bond release at the Colowyo Mine. Monitoring was performed in the interest of ascertaining progress toward revegetation success in general accordance with the proposed technical revision (TR-72) authored by Cedar Creek in early 2008. The data and corresponding success testing in this document are presented under the predication that the technical revision be acceptable to Colowyo and the Colorado Department of Reclamation, Mining, and Safety. Revegetated areas evaluated in 2007 consisted of all or part of 29 units over 777.3 acres in East Pit and West Pit. In addition, two reference areas (Mountain Shrub and Sagebrush) and three benchmark areas were sampled to provide cover and production comparison values to facilitate an evaluation of success for the reclaimed units. Phase III bond release data analysis and presentation by Cedar Creek occurred using the proposed standards for the post-mining land use subcomponent of grazing land. The sample points for Phase III bond release, reference areas, and benchmark areas evaluated in 2007 are provided on Maps 1 - 7. Field sampling for the directly measurable variable of ground cover was systematically conducted from July 27 through August 2, 2007. The growing season prior to and during the sampling period could be qualitatively characterized as above average with regard to precipitation. Sampling occurred immediately following the peak of growth in July. Field efforts in 2007 were conducted by or under the direct supervision of Cedar Creek's Senior Range Ecologist, Mr. Steven R. Viert, Senior Plant Ecologist, Mr. Erik M. Mohr, and Range Ecologist. Mr. Jesse H. Dillon. The remainder of this document is divided into logical sections. Section 2.0 provides the methodology, whereas, Section 3.0 provides results and discussion. Raw data tables are presented in Appendix A. Acreages presented in this document are approximate as determined by Cedar Creek but are based on values provided by Colowyo. Precipitation data presented on Table P and Chart P is the average of two weather stations at the Colowyo Mine (SCN16 and WSTPT). Precipitation in the project area was determined to be above average when compared with the seven-year average for the 2006 / 2007 growing season (September 2006 through August 2007). However, this seven-year average is potentially below the actual long-term average for the mine given that 2001 through 2004 are recognized as below-average precipitation years region wide (drought years). For example, the nearest official weather station (Craig 4SW) received only Phase III Bond Release Page 2 Colowyo Mine