2011-12-06_REVISION - C1981010 - Laserfiche WebLink

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C1981 -010; SL13 December 1, 2011 a total 52% effective cover. For range site B, the required herbaceous cover standard is 29% and 23% litter cover for a total effective cover of 52 %. For range site C, the required herbaceous cover standard is 23.6% and 20.0% litter cover for a total effective cover of 43.6 %. These standards for each of the range sites are listed on Table 4.4 -1 of the permit. For this application, the release block consists of all range A, B and C sites. Therefore, the revegetation standard for range site A was used to evaluate revegetation success since it has the most conservative standard. As discussed above, parcel D -C -99 should be removed from the bond release block so that only 359.5 acres of range site A and B parcels will be considered. The vegetative cover was measured at 20 randomly selected transect points. For each transect, ten points along a fifty meter tape were sampled at random intervals. At each sample interval, the vegetation was sampled using a ten point metal fame, yielding 100 points per transect. The sampling method used meets the criteria outlined in Rule 4.15.11(1) and the permit application. The total effective cover (perennial cover minus noxious weed, plus up to 10% annual /biennial cover, plus the allowable 19% litter cover) measured at the site in 2010 and 2011 was 76.2% and 84.4% respectively. Based on cover data submitted in Table 3. with both the revegetation reports in the SL13 application, the required number of samples taken to substantiate these results was adequate. Also, based on this data, the species diversity standard outlined in the permit was met. Cheatgrass /Downy Brome: Bromus tectorum was included in cover data as an annual /biennial species. Bromus tectorum made up 5.38 % relative cover based on the 2010 cover data and 1.49% in the 2011 data. This annual grass is listed as a noxious weed by the Colorado Department of Agriculture. The Division does not allow plant species listed on the State Noxious Weed list (Department of Agriculture, Conservation Services Division, 8 CCR 1206 -2: Rules Pertaining to the Administration and Enforcement of the Colorado Noxious Weed Act #1) to contribute to Phase III reclamation success. The Division Guidelines; Guideline Regarding Selected Coal Mine Bond Release issues, April 18, 1995, specifically state that, "under no condition will noxious weeds count towards the success standard." Given this, the Division adjusted the cover data submitted with SL13 to remove the cover contribution of Bromus tectorum from the percent allowable cover for each transect. This had a minor effect on the average percent allowable cover. After the subtraction, in both cases the sample was found to be adequate and the success standard was met. I suggest that TMI modify their methods in the future to ensure Bromus tectorum is treated and categorized as a noxious weed when tabulating their data for future bond release applications. Species Diversity , The Trapper Mine uses their plant cover data to determine if their species diversity standards have been met. As listed on page 4 -121a of the permit, the species diversity standard at the Trapper Mine is as follows: 1) At least five principle species including a minimum of four cool season grasses and a minimum of one perennial forb must be established throughout the site. 2) Each of the principle species shall contribute no less than 3% relative cover. 3) No single species shall contribute in excess of 50% relative cover. 4) No four species in combination shall exceed 80% relative cover. Upon review of the cover data supplied by TMI, for both the 2010 and 2011 sample years four principle species of cool season grasses and at least two forb species have established throughout the site. Each of these species contribute no less than 3% relative cover. For 2010, the highest percentage