2021-03-15_REVISION - C1981044 (2)

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of an infestation. For additional information on this effort please see the DRMS interoffice memo of 10 September 2019 and associated imagery. DRMS concluded that weed species comprise a small set, in both numbers and extent and did not appear to significantly impact the establishment of the desired vegetation. Pre Law The pre law area exhibited a mean allowable first hit cover of 31.3%, exceeding the technical performance standard of 30%. Post Law Sample adequacy was achieved in both 2014 and 2015 in the Strip Pit but not in reference area B in 2014. A null test is used when sample adequacy is not achieved. Vegetation data for Strip Pit in 2014 showed a mean allowable first hit cover of 23.3%, less than the 90% of the success standard, 23.5%. In accordance with Rule 4.15.11(2)(b), a t test was used to determine cover success. The calculated t value was 0.071, less than the table t value of 1.330 indicating that the bond release block mean is greater than or equal to 90%of the standard meeting the successful cover criteria. For 2015, sample adequacy for total all hit cover was achieved for both areas allowing for a direct comparison between reclaimed and reference areas as per Rule 4.15.11(2)(a). Mean allowable first hit cover of 31.9%, exceeding the 14.9%cover performance standard. The required cover success criteria for the Pre May 3, 1978 as well as the post law areas have been met. For the two bond release blocks cover vegetation was diverse,well established and mature. Ponds in the Strip Pit with the exception of Pond 9A-P2 which was withdrawn from the bond release request, received permanent designation. The only indication of hydrologic control structures remaining in place comprised permanent on contour ditches and a small swale in the Utah Tract. Contour ditches have filled in with sediment and blend into the reclaimed topography. Erosional features were not observed in either parcel. The vegetative cover was consistent with the vegetation sampling results reported in the SL4 application. Noxious perennial weeds Cheatgrass (Bromus tectorum) and whitetop (Cardaria draba), were present in small, isolated patches that do not pose a threat to the existing mature vegetation. While noxious weeds were encountered at the site, they comprised a small percentage of the vegetative cover. Although, species diversity is not a requirement for phase II bond release,the establishment of a diverse and effective reclaimed community that supports the post mining land use, allows the Division to confirm that the reclaimed area can achieve final reclamation success. Based on the perennial species of grasses, forbs and shrubs observed at the site and as indicated in the SL4 application, the species diversity and composition will support the post-mine land use. Permit Number C1981044 Page 20 of 25