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The Colowyo Mine uses two reference areas for the comparison of success of their <br />reclamation blocks. The reference areas are the sagebrush reference area (established in <br />1981) and the mountain shrub reference area (established in 1980, which is further <br />separated into a mesic aspect and a xeric aspect). Success standards are based on a <br />weighted average of the premining vegetation communities in each reclamation block (as <br />shown on Maps 3 and 4). <br />Permit Page 4.15-16 states that the "...herbaceous cover of the revegetated area will be <br />considered adequate for final bond release if it is not less than 90% of the herbaceous <br />cover as determined from the reference areas with a 90% statistical confidence utilizing a <br />standard students statistical t-test comparison of the means." <br />The reclamation blocks contained in SL-04 were sampled in 2006, 2007, 2008 and 2009 <br />in accordance with the vegetation monitoring plan, detailed on Permit Page 4.15-1. <br />Sample adequacy was determined using the Cochran formula. Both the sampling plan <br />and the sample adequacy determination are acceptable to the Division. <br />Review of Results Partial Phase 11 Bond Release SL-04 Vegetation Sampling <br />Colowyo sampled all of the reclamation blocks that were included in the Partial Phase 11 <br />Bond Release SL-04 in both the 2006 and 2007 sampling years. However, the vegetation <br />sampling data Colowyo provided from 2006 and 2007 includes reclamation blocks that <br />were not included in the Partial Phase 11 Bond Release SL-04. These parcels include <br />FA001, FA002, FA003, S 16002, S 16005, S 16009, S 16011, S 16012, S 16013, S 16015, <br />and S16016. Data collected during the 2006 sampling year from transects 3, 30, 31, 32, <br />34 and 35 fell within the above referenced reclamation blocks. Data collected during the <br />2007 sampling year from transects 4, 33, 34, 35, 36, 38 and 39 fell within the above <br />referenced reclamation blocks. Colowyo cannot use vegetation sampling data from <br />reclamation blocks not included in SL-04 to make a demonstration of successful cover <br />for the Partial Phase II Bond Release SL-04. Colowyo will need to amend the 2006 and <br />2007 vegetation sampling reports to remove the transects that are not in the reclamation <br />blocks included in SL-04. The Division cannot analyze the data provided in the 2006 and <br />2007 vegetation monitoring reports until they are amended and resubmitted. <br />Colowyo sampled all of the reclamation blocks that were included in the Partial Phase 11 <br />Bond Release SL-04 during the 2008 monitoring year with the exception of reclamation <br />blocks S 16010 and S 16014. Data collected at all of the transects during the 2008 <br />sampling year fell within reclamation blocks included in SL-04. The SL-04 reclamation <br />blocks were sampled to adequacy during the 2008 sampling year. Colowyo also sampled <br />both the sagebrush and the mountain shrub reference areas to adequacy during the 2008 <br />sampling year. The live vegetative cover average for the SL-04 reclamation blocks <br />exceeded the weighted average of the two reference areas in 2008. The live vegetative <br />cover for the Partial Phase 11 Bond Release SL-04 reclamation blocks, with the exception <br />of S 16010 and S 16014, is considered successful in accordance with Rule 4.15.7 and <br />Sections 4.15.7 and 4.15.8 of the Colowyo Permit. The following chart shows the 2008 <br />vegetation sampling results.