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Revegetation <br />The thirteen reclamation parcels, totaling 182.5 acres, included in the PartialPhase II and III Bond <br />Release SL -12 are Parcels 16002, 16003, 16005, 16006, 16008, 16009, 16010, 16011, 16012, <br />16013, 16014, 16015 and 16016. All reclamation parcels are located in the Section 16 Pit. Of those <br />thirteen reclamation parcels, Parcels 16002, 16005, 16009, 16011, 16012, 16013 and 16016 are also <br />being requested for Partial Phase Il bond release. All other reclamation parcels being requested for <br />partial Phase III bond release have received Phase II release under previous bond release <br />applications. The seed mixes used for reclamation parcels can be found in Tables 2.05-7, 2.05-8 and <br />2.05-9 in Colowyo's PAP. The post -mining land use for the Phase III Bond Release area is <br />rangeland, as definedby Rule 1.04(71)(c). <br />The Colowyo Mine uses two reference areas for the comparison of success of their reclamation <br />parcels. The reference areas are the sagebrush reference area (established 198 1) and the mountain <br />shrub reference area (established in 1980, which is further separated into a mesic aspect and a xeric <br />aspect). Success standards are based on weighted average of the pre -mining vegetation communities <br />in each reclamation block (as shown on Map 3 and 4 in Colowyo's PAP). <br />Permit Page 4.15-18 states that the "...herbaceous cover of the revegetated area will be considered <br />adequate for inial bond release if it is not less than 90% of the herbaceous cover as determined from <br />the reference areas with 90% statistical confidence utilizing a standard student's statistical t-test <br />comparison of the means." <br />The reclamation parcels contained in SL -12 were sampled in 2013 and 2014 in accordance with the <br />vegetation monitoring plan, detailed in Volume 1, Section 4.15 in the Colowyo PAP. Sample <br />adequacy was determined using the Cochran formula. Both the sampling plan and the sample <br />adequacy determination are acceptable to the Division. <br />Section 16 Pit Bond Release Parcel Results <br />2013 Cover: Herbaceous cover: 47.90% <br />Herbaceous cover standard (90%): 36.93% <br />The 2013 sample data for the Section 16 Pit successfully exceeds 90% of the <br />herbaceous cover standard. <br />2014 Cover: Herbaceous cover: 53.98% <br />Herbaceous cover standard (90%):40.77% <br />The 2014 sample data for the East and West Pit successfully exceeds 90% of <br />the herbaceous cover standard. <br />2013 Productivity: Herbaceous production: 1646.93 lbs/acre <br />Herbaceous production standard (90%): 341.39 lbs/acre <br />The 2013 sample data for the Section 16 Pit successfully exceeds 90% of the <br />herbaceous productivity standard. <br />Proposed Decision and Findings of Compliance December 2017 <br />Partial Phase I1 and III Bond Release SL -12 Page 8 <br />