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I. INTRODUCTION <br />In 1996 the West Elk Mine initiated activities related to expansion of long-term mine <br />facilities in the Sylvester Gulch drainage, which was the location of the dry meadow <br />reference area. In order to address performance standards related to revegetation <br />success and minimize expenditures related to identifying, sampling, and maintaining <br />reference areas for each vegetation community disturbed by mine activities, Mountain <br />Coal Company pursued approval of alternative means of establishing revegetation <br />success criteria for the West Elk Mine from the Colorado Division of Minerals and <br />Geology. The alternative method selected was a historic record approach. During the <br />summer of 1996, Mountain Coal Company and Savage and Savage, Inc. developed a <br />historic record approach to establishing revegetation success criteria specific to the <br />West Elk Mine. The approach was approved by CDMG in Permit Revision No. 07. <br />The approved approach to establishing a historic record, and subsequent revegetation <br />success criteria involved identification and selection of a representative vegetation <br />community which could be sampled in a controlled manner during a range of <br />environmental conditions, specifically, precipitation regimes. After the selection of the <br />historic record vegetation community in concert with CDMG, the selected area was <br />quantitatively sampled for four vegetation parameters; vegetation Grover, herbaceous <br />production, species composition, and woody plant numbers. Additionally, the soil <br />characteristics of the selected area were quantitatively analyzed and evaluated in 1996. <br />Precipitation data over a ninety year period was analyzed to specify a precipitation <br />regime range. A requirement of the historic record approach was to sample the historic -- <br />record vegetation community over a range of precipitation conditions (dry, normal, and <br />wet years). From the historic precipitation records, a "normal" precipitation regime (in <br />inches of precipitation) was developed based on the amount of precipitation received <br />during the eight months preceding the growing season (October through May). <br />Relative to this "normal" precipitation amount, "dry" and "wet" precipitation years <br />were defined, using the standard deviation of the "pre-growing season" precipitation <br />record. <br />The initial quantitative vegetation sampling of the historic record vegetation community <br />took place in 1996. In 1997, the second year of quantitative vegetation sampling was <br />undertaken. While the precipitation regime of 1996 was classified as a "dry" year, the <br />1997 "pre-growing season" precipitation revealed a "normal" year. <br />This report discusses the results of the 1997 vegetation sampling conducted at the <br />historic record study area. This year's results are compared with the sampling results <br />from 1996 at the historic record study area, the dry meadow reference area, and the dry <br />meadow community, to analyze vegetation community responses (total cover and <br />herbaceous production) to varying "pre-growing season" precipitation amounts. <br />-1- <br />