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MCC proposed replacing the two reference areas with the use of a historic reference area <br />for evaluation of revegetation success. The vegetation in the historic reference area <br />resembles the expected post-mining vegetation community. Data is collected in a former <br />agricultural and pasture area southwest of the facilities area as seen on Map 53. Use of <br />the historic reference area was approved in PR-7 and is presented in Section 2.05, page <br />2.05-69 of the permit application. <br />To establish the historic reference, three years of data are to be collected to represent a <br />dry, normal and wet year. A historic analysis was developed using precipitation data <br />from the National Climatic Data Center (NCDC) for the Paonia 1 SW station collected <br />from 1905-1965. Data from the "pre-growing" season, October through May, were <br />considered. The average annual precipitation during the "pre-growing' season was 11.08 <br />inches. From this data it was decided that wet and dry years would be those years during <br />which the precipitation varies by more than one standard deviation from the mean. The <br />standard deviation was 2.63. Thus, precipitation during a "dry" year would be less than <br />8.45 inches and during a "wet" year, precipitation would be greater than 13.71 inches <br />from October through May. As conditions permit, West Elk will collect data in <br />representative years and submit the data to the DBMS. <br />Shrubs will be re-established to a minimum standard of 1,000 stems per acre. This <br />criterion was established by the Colorado Division of Wildlife. For specific information <br />regarding this criterion, see Exhibit 62 in the permit document. <br />The proposed post-mining land use is rangeland and wildlife habitat. Tables 48 and 49 of <br />the permit document list the seeds and shrubs to be planted to establish this land use. The <br />West Elk Mine also will reclaim 1.3 acres within a riparian buffer zone. The riparian <br />seed and shrub mix is listed on page 2.05.53 of the permit document. The mine based <br />their selection of plant species on species listed in the baseline biological survey, species <br />geographical range, soils, climate, slope and aspect, root competition, cover and seasonal <br />variation. Seed mixes are also based on experience gained on West Elk Mine <br />revegetation plots, and quantitative data collected in 1980 describing the present <br />vegetative cover, and in terms of wildlife requirements suggested in literature. The <br />Division approves the use of these species based on the post-mining land use. <br />Once the topsoil has been distributed and graded, the surface is prepared for planting. <br />Surface preparation loosens and roughens the surface by disking, harrowing, or dragging <br />which increases infiltration and reduces surface runoff. Seeding and planting are <br />conducted parallel to the contour unless such activities prove hazardous to equipment <br />and/or operators. Various conditioners and neutralizers may be used to modify the <br />seedbed conditions. Seeding and shrub planting will be done during the spring (March 15 <br />through June 15) or fall (September 15 through November 15). <br />The grasses and forbs are seeded primarily by drill seeding. Broadcast of seed is utilized <br />on small areas, with hydroseeding used on areas with slopes steeper than 3:1. Shrubs are <br />planted in conjunction with seeding operations. The shrubs will be planted after the <br />45