2015-10-13_REVISION - C1981014 (18)

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2013. The New Portal Reference Area was sampled on September 6 & 7, 2013. The Vento Portal Reclamation was sampled on August 29, 2013 and September 9 & 10, 2013. The Old Portal Reference Area and the Corley Reclamation were sampled between August 31 - September 4, 2013. The field sampling efforts for the Loadout Reference Area and the Loadout Reclamation were performed between August 27 - 31, 2013. At the time of the field sampling, plants were actively growing and near the period of optimum plant growth, when the plant cover and forage production were near their maximum. A total of 107 different plant species were either encountered or observed in sampling of 165 cover transects, 240 forage production and 200 shrub density transects sampled in this evaluation. The compiled plant species listed collected is presented in Table 1, Southfield - Mine Plant Species List. Sample Adequacy. A statistical summary and analysis of the data collected to characterize the plant cover, forage production and woody plant densities are presented in Table 2, 2013 Statistical Summary and Sample Adequacy Calculations. This table documents that a sufficient number of samples were collected to describe the parameters of "plant cover," and "forage production" at the 90% confidence interval or the required minimum sample size as required for the "reverse null" statistical comparison, defined in Section 4.15.11 (2)c of the CDRMS regulations was achieved. Transect Locations. The locations of all of the plant cover, forage production and shrub density transects are shown on the enclosed maps. The specific details corresponding to each reclamation area or reference area sampled are discussed for each area individually. REFUSE PILE REFERENCE AREA Plant Cover. Results of the 15 cover transects are found in Table 3, Refuse Pile Reference Area - 2013 Plant Cover. Total plant cover averaged 29.00% and litter averaged 41.27%. "Allowable plant cover" averaged 28.67%. Perennial grasses and grasslikes dominated the plant cover, contributing 24.33% of the total plant cover or 83.91 % of the total plant relative plant cover on this reference area. Woody plants consisting of trees, shrubs and half -shrubs was the second most dominant plant life form, contributing 3.73% of the total plant cover and 12.88% of the total plant relative plant cover. Annuals was the third most dominant plant category, contributing 0.33% of the total plant cover and 1.15% of the total relative plant cover. Perennial forbs contributed 0.34% of the total plant cover or 1.15% of the total relative plant cover. Succulents contributed 0.27% of the total plant cover or 0.92 percent of the total relative plant cover. Blue Grama was the dominant plant species, contributing 18.27% of the total plant cover and 62.99% of the total relative plant cover. Sand Dropseed, One -seed Juniper and Western Wheatgrass were the other dominant species, contributing 9.43%, 8.28% and 7.13%, respectively, of the total relative plant cover on this area. The locations of the 15 cover transects are shown on Map 2, Refuse Pile Reference Area - 2013 Transect Location Map. The sample adequacy calculations in Table 2, 2013 Statistical Summary and Sample Adequacy Calculations, document that the number of samples required to describe this site at the 90% confidence interval with respect to both "total plant cover" and "allowable plant cover," was 2.5 transects. These calculations mean that a sufficient number of