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Don Macdonald; CEC <br />2011; ARR Review <br />April 3, 2012 <br />Area 31 <br />Vegetation Cover <br />Page 5 of 6 <br />The monitoring report indicates the total mean vegetative cover for RA 31 was measured to be 38.4 %. This <br />includes 27% cover contributed by graminoid species and 11.4% cover contributed by forb species. The relative <br />cover percentages reported on Table 4. of the vegetation monitoring report does not appear to be correct. The <br />Division recreated Table 4. and calculated a different relative cover percentage for all of the species. The <br />vegetation monitoring report indicated graminoids accounted for 70.1% relative cover and forbs account for <br />29.9% relative cover. Based on the Divisions analysis, graminoids accounted for 70.31% relative cover and forbs <br />accounted for 29.69% relative cover. It is unclear how the reported relative cover percentage was determined. <br />The reported total mean vegetative cover of 38.4% included contributions of Cheatgrass and several <br />annual/biennial species. According to the monitoring report, Cheatgrass accounted for 8.8% of the total mean <br />vegetative cover (Table 4.). Based on the Divisions analysis, 29.69% of the relative cover is contributed by <br />annual/biennial species (not including Cheatgrass). The Division subtracted out the percent cover contributions of <br />Cheatgrass and the percent cover contributions of annual/biennial plants in excess of allowed amount. Based off <br />this, the Division determined the total mean vegetative cover to be 21.16 %. <br />The dominant species reported at the site are Prairie Sandreed (Calamovilfa longifolia), Cheatgrass, Curlycup <br />Gumweed (Grindelia squarrosal) and Black Medic. <br />CEC determined the 2011 success standard for cover to be 35.41% based on the precipitation measured for that <br />growing season in accordance with their approved permit. 90% of the success standard is 31.87 %. By a direct <br />comparison, RA 31 does not exceed the success standard for cover or 90% of the approved success standard. <br />Production <br />The vegetation monitoring report indicated the total herbaceous production for RA 31 was 168.87g/m ^2. The <br />production success standards for 2011 was reported to be 127.65g/m ^2 based on the approved predictive <br />equation. It is unclear if the success standard has been met for 2011 because the amount of production <br />contributed by noxious weeds or annual/biennial species was not reported. <br />Species composition <br />Based on the reported values, one perennial warm season grass and one perennial cool season grass meet the <br />species composition criteria. The Divisions analysis of the data agrees with the reported findings. Two additional <br />perennial warm season grasses are necessary for RA 30 to meet the revegetation success criteria for species <br />composition. <br />Vegetation Monitoring Summary and Conclusion <br />The post mining land use approved for the Keenesburg Mine is designated as rangeland with small portions of <br />industrial commercial sites for hydro- carbon production. The success standards for cover, herbaceous production <br />and species composition were set in order to quantitatively measure if the post mining land use has been achieved. <br />In order to be considered for bond release, the statistical adequacy of the measures must be demonstrated in <br />accordance with Rule 4.15.11. However for the purpose of this report, statistical adequacy was not analyzed. <br />Total mean vegetation cover found in RA 29 and 30 would meet the success standards, but RA 31 would not. <br />Based on the Divisions analysis of the data and relative cover percentages, none of the reclamation areas would <br />meet the success criteria for species composition. However, RA 29 and 30 nearly meet the success standard for <br />