2013-07-24_REVISION - C1980007 (8)

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II Bond Release SL-04 application package. The permanent seed mix shown in Table 37 of the PAP was used for all sites. All acreage under consideration for Phase II Bond Release has been approved for Phase I Bond Release. Live vegetative cover was determined by an acreage-weighted distribution of random cover transects. The discontinuous reclaimed areas were divided into nine (9) sample groups by year of reclamation. Additionally, each of the nine groups was ecologically similar. The operator determined that a minimum of 30 vegetation transects would be collected. The 30 transects were allocated proportionally among the sample groups based on a weighted acreage percentage. Each transect was then randomly located on a specific reclamation area using random start locations. The start locations were determined by gridding the sample areas using a 50-foot by 50-foot grid. Fifty sample points were collected at each location along 25-meter transects. Sample adequacy was achieved for vegetative cover using the 30 transects. Live vegetative cover equaled 57.53%, with only 0.47% attributed to noxious species. The noxious species included Canada thistle (0.33%), hounds tongue (0.07%), and musk thistle (0.07%). Subtraction of the noxious species from the total cover value resulted in a non-noxious cover value of 57.06%. The approved cover standard for the reclaimed areas is 53.04% live vegetative cover. West Elk’s revegetation is considered successful if they achieve 90% of the required 53.04% cover value at a 90% confidence level. West Elk exceeded the approved standard of 53.04%. Finally, the Division allows for up to 10% of the relative vegetative cover to consist of annual and biennials. Only 6 annual or biennial species were sampled on the reclaimed areas, accounting for 4.06% relative vegetative cover. This contribution of annual/biennial species is acceptable and no adjustment of the cover data is required. Based on the approved reclamation plan and the vegetation monitoring report included in the SL-04 application, the Division finds that the West Elk Mine has achieved the Phase II reclamation success criteria in accordance with Rule 3.03.1(2)(b). Soil Loss Pursuant to Rule 3.03.1(3)(b), “No more than sixty (60) percent of the bond shall be released so long as the lands to which the release would be applicable are contributing suspended solids to streamflow or runoff outside the permit area in excess of premining levels as determined by baseline data or in excess of levels determined on adjacent nonmined areas...” In their SL-04 application, MCC provided a demonstration of pre-mining and post-mining sediment loss for the Phase II Bond Release areas. The demonstration used the Revised Universal Soil Loss Equation (RUSLE), which is a method for demonstrating pre-mining and post-mining soil loss approved by the Division. The average pre-mining sediment yield from the Phase II reclamation areas was calculated at 13.68 tons/acre/year. The post-mining sediment yield for the Phase II reclamation areas was calculated at 3.03 tons/acre/year. The soil loss data confirms what was observed on the bond release inspections. The reclaimed areas had more vegetative cover than the surrounding, Proposed Decision and Findings of Compliance 7 July 2013 Partial Phase II Bond Release SL-04 Page 5