2014-12-19_REVISION - C1980005 (2)

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Woody Plant Density The success standard for woody plant density on the Seneca II Mine site consists of two requirements. The first criterion for determination of woody plant success requires 90% of a minimum of 100 stems per acre in the total BRB, or background area. The second criterion requires that at least 5% of the BRB contain a concentration of 90% of 1000 stems per acre. SCC identified "concentrated" shrub areas using aerial photography collected in 2009. Any reclaimed area within the BRB -5, but outside of the concentrated shrub areas, was considered "background ". BRB -5 2011 woody stem density sampling in background areas resulted in 554.4 stems per acre. Woody stem density did not achieve sample adequacy in 2011, but SCC collected a minimum of 30 sample transects. SCC provided a reverse t -test demonstration to validate that the sample value of 554.4 woody stems per acre surpassed the required 90 stems per acre in the background reclamation area. SCC measured 2035 stems per acre in concentrated shrub areas within BRB -5 in 2011. The concentrated shrub areas comprised 19.0 acres, or 7% of BRB -5 acreage. Woody stem density did not achieve sample adequacy in the concentrated shrub areas in 2011, but SCC collected a minimum of 50 transects, and conducted reverse null t -test calculations to validate the 2011 concentrated shrub success. The Division finds the data and calculations acceptable and finds the woody stem density establishment successful for 2011 in BRB -5. BRB -5 2012 results in background areas resulted in 210.4 stems per acre. Woody stem density did not achieve sample adequacy in 2012, but SCC collected an excess of 30 (53) sample transects. SCC provided a reverse t -test demonstration to validate that the sample value of 210.4 woody stems per acre surpassed the required 90 stems per acre in the "background" reclamation area. SCC measured 1614.7 stems per acre in concentrated shrub areas within BRB -5 in 2012. The concentrated shrub areas comprised 19.0 acres, or 7% of BRB -5 acreage. Woody stem density did not achieve sample adequacy in the concentrated shrub areas in 2012, but SCC collected a minimum of 53 transects, and conducted reverse null t -test calculations to validate the 2012 concentrated shrub success. The Division finds the data and calculations acceptable, and finds the woody stem density establishment successful for 2012 in BRB -5. The Division finds that SCC has achieved reclamation success on BRB -5 based on sample results collected in 2011 and 2012. In accordance with Rule 4.15.8(2) and permit requirements, reclamation is successful for vegetative cover, herbaceous production, species diversity and woody plant density. Post Mining Land Use The post- mining land use for the Seneca II Mine is rangeland for enhanced domestic livestock grazing and wildlife habitat. The reclaimed lands have vegetative cover composed of a variety of grasses, forbs, and woody shrubs. The seasonality and forage characteristics of the vegetative species are suitable for the approved post- mining land use. No significant weed problems or bare areas were identified. The revegetation success standards were based on what would be necessary for the land to properly function as grazing and wildlife habitat. Based on the achievement of the requirements, the Division