2012-12-06_REVISION - C1981008 (4)

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Required Topsoil Sample Point Thickness (ft) Thickness (in) Thickness (in) Phase II Area 1 23 -39 TS54 4.0 48 efforts on either the reclaimed or reference areas. As recommended in the DRMS Guideline, the cover data for all annuals and biennials has been deleted from the "allowable plant cover" revegetation success comparisons. 4. Alluvial Valley Floor and Cropland Productivity: For reclaimed alluvial valley floors (AVF), and croplands (other than prime farmlands), an adequate sample of production collected from the reclaimed area and the approved reference area during a single year is needed. Agricultural productivity will be considered acceptable if the crop production from the AVF or cropland is at least 90 percent of the production from the approved standard. Documentation must also be presented that the essential hydrologic functions have been restored, for alluvial valley floors. Vegetation cover and species diversity demonstrations are not applicable to croplands, but are applicable to non - cropland alluvial valley floors. Response: There are no alluvial valley floors or croplands in the release areas covered by this application. 5. Topsoil Replacement Methodology: A map or description of topsoil replacement thickness, and replacement documentation methodology. This will be compared to the approved topsoil replacement plan. Response: Map R -3 shows the topsoil replacement thickness in the Phase II area along with the years that topsoil was placed in these areas. The topsoil over both areas was replaced in accordance with the approved topsoil redistribution plan found in Section 2.05.4(2)(d). As can be seen in the Phase II topsoil thickness samples table below, topsoil was placed at a sufficient thickness in both Phase II areas. The average thickness in Area 2 is only lower than the approved thickness due to sample point TS51. TS51 is located just south of BB Road (Map R -3). Topsoil is always thinner near roads, due to the presence of the outside slopes of the underlying road bed spreading out onto adjoining land. Therefore, point TS51 should be removed from the calculation of the average topsoil thickness for Area 2. Without TS51, the average topsoil thickness over Area 2 is 43 inches. This satisfies the minimum required post -mine topsoil thickness of 37 inches for this area. Table 1 - Phase II Area - Topsoil Thickness Samples Table' SL -14 03DEC12.wpd 28