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CEC has applied for Phase II bond release on 29.34 acres in parcels 31, 32, and 33. Parcel 31 was <br />seeded in 2009, Parcels 32 and 33 were seeded in 2015. The vegetative cover on all three parcels was <br />very good. The vegetative communities were dominated by warm season grasses. <br />Vegetative sampling for reclamation success was conducted in August 2018. All three parcels were <br />sampled to adequacy. Sample transects were randomly generated on a grid. <br />Phase II vegetative success is requires vegetative cover to meet 90% of the reclamation success <br />standard. (Permit Section 2.05.4) Vegetative cover success for the Keenesburg mine is based upon a <br />predictive equation approved by the Division and the previous 11 months precipitation values. The <br />operator recorded 14.9 inches of precipitation for the previous 11 months record, September 2017 <br />through July 2018. <br />For the 2018 vegetation sampling event, the live vegetation success standard was calculated as: <br />37.3% (90% of the standard =33.57%). The following allowable vegetative cover was measured in <br />the bond release blocks in 2018: Area 31= 37.1 %, Area 32: 37.6%, Area 33: 42.3%. Each of the <br />three bond release parcels exceeded the 90% standard value. The Division determines that the bond <br />release block is successful for live vegetative cover for SL10. <br />Although species composition is not a requirement for phase II bond release success, the Division <br />evaluates the vegetation data at Phase II bond release to see how the reclaimed community is likely to <br />achieve species composition standard in the near future. The species composition for the Keenesburg <br />mine is considered successful when there are 4 perennial species, three of which are warm season <br />grasses and on is a cool season grass. Each species should contribute a minimum of 3% relative <br />cover, yet no more than 40% relative cover. Species may be native or introduced, but may not be <br />considered noxious or prohibited species. <br />CEC has provided vegetation species data to demonstrate that the reclaimed parcels are achieving or <br />approaching the species composition standard. All bond release parcels are dominated by warm <br />season grass species. This is expected based upon the seed mix, the climate and the post -mining land <br />use. <br />In the Area 31 parcel 3 cool season grasses were present; Indian ricegrass, Crested wheatgrass and <br />Needle and Thread grass, with an allowable relative cover of 0.4%. Eight species of warm season <br />grasses contributed a combined total of 95.4% allowable relative cover. Although no one cool season <br />grass species contributes 3%relative cover or greater, the presence of the three cool season species <br />and eight warm season species support that the established vegetation community is approaching <br />adequate diversity. The Area 32 parcel exhibited 4 cool season grass species, Indian ricegrass, <br />Thickspike wheatgrass, Bluebunch wheatgrass, and Tall wheatgrass. Blue bunch wheatgrass <br />contributed 7.8% allowable relative cover, with the sum of all 4 cool season grasses contributing <br />9.5% allowable relative cover. Eight warm season grasses contributed a total of 90.2% allowable <br />relative cover. Three of the warm season grasses; blue grama, Prairie sandreed, and Sand dropseed <br />contributed greater than 3% allowable relative cover. Prairie sandreed contributed greater than 40% <br />allowable relative cover. However, the presence of the additional species assures that this reclaimed <br />community is not becoming dominated by a single species. Area 33 parcel was found to have 6 cool <br />Keenesburg Mine C1981-028 SL -10 Page 6 of 9 <br />