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3.0 RESULTS <br />3.1 QUANTITATIVE EVALUATION: PRE-SMCRA RECLAIMED AREAS <br />The eligible pre-SMCRA reclaimed areas range from 0.3 to 3.3 acres in size and range in age <br />from 8 to 23 years. The location, size, and age of the reclaimed sites are provided in the <br />Appendix. Specific vegetation information for the pre-SMCRA reclaimed areas is contained <br />in Tables 1 and 2. <br />3.1.1 Total Vegetation Cover: Pre-SMCRA Reclaimed Areas <br />Fifteen quantitative cover samples were collected in the pre-SMCRA reclaimed areas. Total <br />mean live vegetation cover of the pre-SMCRA reclaimed areas was 57.73 percent. Graminoids <br />provided 23.87 percent mean vegetation cover, forbs accounted for 29.87 percent mean <br />vegetation cover, and woody species contributed 4.00 percent mean vegetation cover. <br />The most frequently encountered species was Lepidium perfoliatum (pepperweed), present in <br />93 percent of the 15 transects sampled for vegetation cover. Agropyron smithii (western <br />wheatgrass) and Bromus tectorum (cheatgrass) were found in 87 percent of all transects. <br />Convolvulus arvensis (field bindweed) was present in 80 percent of transects, and Medicago <br />sativa (alfalfa) was encountered in 67 percent of the cover transects. All other species were <br />encountered in fewer than fifty percent of the vegetation cover transects. <br />Vegetative litter (prior years growth, dead wood, and other biologic organic material) <br />comprised 19.20 percent ground cover overall within the pre-SMCRA reclaimed areas. Bare <br />soil comprised 16.53 percent of the ground cover. Rock accounted for 6.53 percent of the <br />ground cover sampled. <br />3.2 COMPARISON OF RECLAIMED AREAS WITH THE PHASE III RE - <br />VEGETATION SUCCESS CRITERION <br />Comparison of the reclaimed area mean for total live vegetation cover for pre-SMCRA <br />reclaimed areas with the total live vegetation cover bond release success criterion indicates <br />whether revegetation has been successful and compliant with requirements for Phase III bond <br />release. CDRMS Rule 3.03.1(2) provides for release of bond, "upon the establishment of <br />vegetation which supports the approved post- mining land use and which meets the approved <br />success standard for cover..." Applicable Rule 4.15.10(1) requires that the minimum ground <br />cover of living plants shall not be less than can be supported by the best available topsoil or <br />other suitable material in the areas, shall not be less than the ground cover existing before <br />redisturbance, and shall be adequate to control erosion. The final bond release vegetation <br />success criterion for cover was developed and approved in Technical Revision 77. The total <br />live vegetation cover success criterion is 19.3 percent. <br />Oxbow Mining, LLC Elk Creek Mine Page 6 <br />2019 Phase III Bond Kelease Pre-5MCKA Vegetation Report <br />