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Date: June 11, 2010 To: Rob Zuber From: Janet Bin Re: Keens g T 1981-02k Phase II BoAd Release SL5 application review. I have review?e I?e? us rg Mine application for a phase II bond release application for reclamation areas 2, 5, 6, 7, 9, 10, 15, 16, 23 and 29. Coors Energy Company (the operator) sampled these reclaimed areas as combined Bond Release Block (BRB). This is acceptable the Division based upon topsoil replacement thickness and methods, dates and timing of seeding, topography, seed mix used and land management. This BRB meets the definition of a logical land management unit as defined in the Division's Guideline Regarding Selected Coal Mine Bond Release Issues (April 18, 1995). The operator sampled the BRB Between August 5 and August 15, 2009. I have one question for the operator: 1) Table 3, titled "Vegetative Cover: 2006 Reclamation Area (2009)" indicates that this data was collected from Area 29. Area 30 was reseeded in 2006 and Reclamation Area 29 was reseeded in 2003. Is this Table 3 data meant to represent data from Area 30 or Area 29? Please provided a corrected Table 3 for the record. The following is my review of the presented data: Reclaimed areas seeded in 1998, 1999, and 2000 (Reclamation areas 2, 5, 6, 7, 9, 10, 15, 16 and 19) meet the reclamation standard for cover. In 2006 the operator requested a revision to the reclamation success standards from comparison to an approved reference area, to comparison to calculated cover and production standards derived from historic reference area data. Precipitation from September to July immediately preceding the sampling event is incorporated into the standard formula as the variable. The Division approved this revision (TR37, approved 6/15/2006), thereby removing any direct comparison with species composition in a reference area. The calculated live vegetative cover (LVC) value using the measured 13.71 inches of precipitation for the preceding September to July resulted in a cover standard of 35.69% LVC. The operator reported in the 2009 vegetation sampling report that the overall vegetative cover for this sampling block was 60.96% live vegetative cover. However, reference to Rule 4.15.1(2) and the Division's 1995 Bond Release Guidelines, noxious species can not contribute to reclamation success. Therefore, the cover attributed to Bromus tectorum (Downy brome) must be subtracted out of the live vegetative cover value. Table 2 shows that Bromus tectorum contributed 8.3% to the live vegetative cover (LVC) on this block. Therefore, 60.96% cover minus 8.3% cover attributed to Bromus tectorum results in LVC of 52.66% LVC. Furthermore, Division policy and direction provided by the Division's 1995 Guideline notes that "the allowable cover contribution of annual and biennial species should not exceed 10 percent or the relative cover of such species in the associated reference area or approved technical standard, whichever is higher." Of the thirty-six plant species sampled on the 1998/1999/2000 Reclamation block, fourteen species were determined to be annual or biennial. After removal of cover attributed to the one noxious species (Bromus tectorum), the Division can allow up to 10 percent relative cover of the remaining annual and biennial species to count towards reclamation success for cover establishment. The fourteen annual or biennial species contributed 13.19% cover, or 28.67% relative cover to the total cover value. Allowing up to 10% relative cover attributed to annual or biennial species to count towards the cover success value, this means that 18.67% relative cover or 8.59% total cover would be removed from the cover values. Therefore, 52.66% LVC minus 8.59% LVC, equals 44.07% LVC. The calculated value using the measured 13.71 inches of precipitation for the preceding September to July resulted in a cover standard of 35.69% LVC. The live vegetative cover measured on the 1998/1999/2000 reclaimed block exceeds the calculated cover standard and is considered successful for the 2009 sample year. This bond release block was sampled to statistical adequacy. "No woody species are required for bond release. Coors Energy Company has a noxious weed management plan and actively implements it. Only one noxious weed species, Cheatgrass, was measured in the 2009 vegetation sampling. Cheatgrass, or Bromus tectorum. Coors Energy Company has implemented its approved weed management plan to control Cheatgrass in the reclaimed areas. Bromus tectorum is considered a noxious Keenesburg SL5 Memo 1 June 11, 2010