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West Efk Mine <br />In the reference area for the dry meadow community, the total vegetation cover was slightly higher <br />at 46.8 percent (Exhibit 32). The dominant species were also western wheatgrass, smooth brome, <br />and Kentucky bluegrass. These grasses accounted for about 87 percent of the total vegetation cover. <br />Common forb species included morning-glory, dandelion and Oregon fleabane (Erigeron <br />speciosus).. Total production for the affected dry meadow-was 278.86 grams per square meter. <br />Grasses accounted for 94 percent of the total biomass (Exhibit 32). Western wheatgrass was the <br />most productive species with -187.23. grams per squaze meter. Perennial and annual forbs provided <br />about 6 percent of the total biomass. <br />In the reference azea, the total production was 363.91 grams per square meter (Exhibit 33). Grasses <br />were most important, and accounted for 351.33 grams per square meter. Western wheatgrass and <br />smooth brome were the most productive species with 249.30 and 96.02 grams per square meter, <br />respectively. Perennial forbs accounted for 3 percent of the total. Annual forbs were of very minor <br />importance, accounting for less than 0.1 percent of the total biomass. <br />The affected area had a greater species diversity with 6.3 species per square meter while the <br />reference plot has 4.4 species per square meter. The difference was related to the higher number of <br />forb species encountered in the affected area. Most of the forb species were weeds and are <br />characteristic of disturbed areas. <br />As mentioned eazlier, the ]azge meadow in the affected azea appeazed to have been bulldozed. It <br />should, therefore, be recognized that many meadow communities occur as a function of human <br />manigulation. As such, they may not be in a state of equilibrium with the surrounding environment. <br />The level of management on both the affected and reference areas of the dry meadow vegetation <br />type has been similaz over the years. Both areas were close to homesteader's cabins and were <br />probably cleazed to provide acreage for crops and gazdens. In addition, Mr. Hazold Ross has grazed <br />livestock on both areas for the past 25 years. Thus, both areas have been subject to human <br />manipulation in terms of brush clearing and grazing by livestock for an extended period. These <br />considerations were evaluated during the reference azea selection process,-and for these reasons, <br />MCC believes that the dry meadow vegetation type reference area is as compazable to the affected <br />area as can be reasonably expected. <br />In order to evaluate the similarity between the dry meadow control and affected azeas, t-tests were <br />conducted on the cover and productivity data. In both tests, the difference was significant. The <br />reference area had significantly higher cover and production. <br />As a second means of comparison a similarity index between the affected area and reference azea <br />was calculated on the basis of relative cover (percent of total cover). The percent similarity was <br />obtained by summing the amount of relative cover shazed by each of the species in the affected and <br />reference areas. On this basis, the two areas were 69.2 percent similaz. <br />Even though the reference area has significantly greater cover and production, MCC still considers <br />it a suitable site for a reference area. It is the only comparable site located neaz the affected area and <br />outside the area of mining activity. Also, because the cover and production reclamation standards <br />based on this reference area would ensure that the affected areas aze more than .adequately <br />reclaimed. <br />2.04-148 RrviseAApri(2004 PRIG <br />