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Consistent with pre -disturbance vegetation boundaries, and disturbed area mapping, the <br />weighting factors for the reclaimed areas at the Southfield Mine will be 79.8 percent for <br />grassland/Refuse Pile reclamation and 20.2 percent for the pinion/juniper woodland type, <br />corresponding to the Vento Portal and Corley reclaimed areas located on the old surface <br />facilities area. Based upon detailed measurements taken of these reclaimed areas in the fall of <br />2013, the 20.2 percent factor for the mine facilities area will be subdivided as follows: <br />The weighting factor for the Vento Portal reclaimed area will be 9.41 percent and the <br />weighting factor for the Corley reclaimed area will be 10.99 percent. The contribution from <br />the Refuse Pile, Vento Portal and Corley reclaimed areas will then be summed into the <br />composite final revegetation weighted average value to represent the reclaimed areas at the <br />Southfield mine, similar to the approach outlined for the three reference areas described on <br />pages 2.04.10-4, 2.04.10-5 and 2.04.10-5a. <br />Vegetative productivity of reclaimed areas will be evaluated by clipping one-quarter square <br />meter circular quadrates along the sample transect. All plant species will be clipped, dried and <br />weighed and determine total vegetative production. If the absolute value of production from <br />the reclaimed area is greater than or equal to the calculated 90 percent confidence level for the <br />weighted -average reference area value, then the corresponding means shall be determined <br />statistically equivalent and vegetative productivity for the reclaimed area will be judged to be <br />adequate to meet regulatory revegetation success standards. <br />Species diversity will be evaluated for revegetated areas utilizing data from vegetative cover <br />sampling. Species diversity shall be considered adequate when the four (4) dominant species, <br />based on plant cover, comprise no more than 80 percent of the total species composition. <br />The final warm season grass vegetation success standard for all the reclaimed areas at both <br />the Southfield mine and the Southfield Loadout will consist of the number of warm season <br />grasses having relative percent composition values greater than 3 percent as identified in. the <br />2013 and 2014 Phase III revegetation monitoring reports for the four currently approved <br />reference areas. The final warm season species diversity revegetation success criteria will be <br />based on a weighted average factor, based upon the acreages of the four currently approved <br />reference areas in calculating the final warm -season species diversity revegetation success <br />standard. <br />Conventional statistical analysis methods will be used to evaluate woody plant densities on <br />reclaimed areas within the Mine Area and for both vegetation reference areas. Woody plant <br />density for seeded areas and the reference area will be measured using 50m x 1 m belt <br />transects along the same transect lines. This data will be combined with direct count woody <br />plant density data for the shrub clumps using a weighted average approach. The "t-test" <br />method (Larson, 1980) will be used to evaluate similarity of woody plant densities between <br />the weighted average reclaimed area value and the corresponding reference area or, in the <br />case of the grasslands type, the revised woody plant count. <br />TR45 2.05.4-27 Revised 07/15/15 <br />