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Page 6 of 9 <br />for the Irrigated Pasture Reference area and Area 6, utilizing the information presented, the Division was <br />able to review and verify the results of sampling using Microsoft Excel®. <br />Total plant cover measured in the Reference Area was reported to be 61.47 %; this included all the plant <br />life forms such as perennial grass and grasslikes, perennial forbs, annual and biennials, and noxious weed <br />species. The applicant also reported what they believed to be the "allowable cover" percent used to <br />determine the revegetation success criteria for Irrigated Pasture Reclaimed Areas. They included the <br />cover attributed from perennial grasses and grasslikes and perennial forbs, but they excluded annual and <br />biennial species and noxious weeds in the measure of "allowable cover ". The "allowable cover" <br />percentage was reported to be 58.67 %, making the success standard for cover to be 52.80% (90% of <br />58.67 %). The dominant species found in the Irrigated Pasture Reference Area were Meadow Fescue <br />(Festuca pratensis), Quackgrass (Agropyron repens), Tall Fescue (Festuca arundinacea), Small- winged <br />Sedge (Carex micropteral), Kentucky Bluegrass (Poa pratensis), Baltic Rush (Juncus balticus) and Fowl <br />Bluegrass (Poa palustris); contributing 24.4, 10.83, 10.09, 9.11, 8.03 and 6.83 percent of the relative <br />cover at the site respectively. The Division does not consider state listed noxious weeds as contributing <br />to the successful establishment of the post mine land use and in accordance with our "Guidelines <br />Regarding Selected Coal Mine Bond Release Issues, " dated April 18, 1995, the Division requires all <br />noxious weed contributions to cover and production be deleted from both reference and reclaimed area <br />data prior to success comparison of those parameters. Based on the Division's review of the data, the <br />applicant included two species in the "allowable cover percentage" that are currently on the State noxious <br />weeds list, Quackgrass and Field Bindweed (Convolvulus arvensis). The applicant argues these species <br />are not currently on the Montrose County noxious weed list and thus were included in the "allowable <br />cover" measurement. The Division re- categorized these species as noxious weeds and found the <br />"allowable cover" percentage to be 51.60 %, thus making the success standard for cover to be 46.44 % <br />(90% of 51.6 %). <br />For Area 6 (IP -4 area), the applicant found the total plant cover and the "allowable cover" to be 81 %. <br />The dominant species encountered included Alfalfa (Medicago sativa), Orchardgrass (Dactylis <br />glomerata) and Meadow Brome (Bromus biebersteinii) contributing 50.86, 22.63 and 16.54 percent <br />relative cover respectively. Similar to the Reference Area, the applicant included Quackgrass and Field <br />Bindweed in the "allowable cover" measurement. The Division re- categorized these species as noxious <br />weeds and found the "allowable cover" to be 79.07 %. These species were not as prevalent in the <br />Reclaimed Area as opposed to the Reference Area. This is likely due to the fact the Reference Area is <br />dominated by perennial grasses and grasslike species where the Reclaimed Area is dominated primarily <br />by Alfalfa, a perennial forb. <br />Based on the Division findings, the success standard for allowable plant cover for 2010 based on the <br />reference area is 46.44 %; the allowable cover found on the Area 6 (IP -4) was 79.07 %. Sample adequacy <br />was demonstrated for both the sample efforts on the reclaimed and the reference area. Given this, in <br />accordance with Rule 4.15.8(3)(a) the vegetative cover found on Area 6 exceeds the success standard <br />derived from the Irrigated Pasture Reference Area. <br />As indicated above, revegetation will be deemed successful if the herbaceous production of the reclaimed <br />irrigated pasture is greater than 90% of the herbaceous production of the Irrigated Pasture Reference Area <br />after the weighted average soil adjustment has been applied. According to the 2010 revegetation <br />monitoring report, weighted average soil adjustment factor for reclaimed area IP -4 (Area 6 in SL14), was <br />found in the 2009 revegetation monitoring report. This parcel of land was not evaluated in the 2009 <br />revegetation monitoring report submitted to the Division for SL14. The applicant will need to provide a <br />demonstration of how the weighted average soil adjustment factor was calculated for Area 6. This issue <br />is further discussed below. In the 2010 revegetation monitoring report they used .728 as the weighted <br />average soil adjustment factor. The Division used this number to evaluate and review the production <br />data. <br />