2010-06-11_REVISION - C1981028 - Laserfiche WebLink

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The operator measured total vegetative cover on areas 23 and 25 to be 61.20% in 2009. As noted previously noxious species cannot count towards the vegetative cover success. Two species were identified as noxious species based upon the Colorado State Department of Agriculture Noxious Weed List; Bromus tectorum (Cheatgrass), and Tribulus terestris (Puncturevine). Subtraction of these two species from the vegetative cover results finds the vegetative cover value for the 2009 sampling event to be 47.8% live vegetative cover (LVC). If this reclamation block had been sampled to adequacy, the Division would have been able to find that the 2002 Bond Release Block (BRB) had achieved the reclamation success for vegetative cover. Required vegetative cover for 2009 sampling is 35.69% LVC. Species composition evaluation for the 2002 BRB found only one warm season grass meeting the minimum greater than 3% relative cover requirement. Species composition success was not achieved for the 2002 BRB for the 2009 sampling event. The operator provided herbaceous production data for the 2002 BRB. Sample adequacy was achieved for the 2009 herbaceous production sampling event for the 2002 BRB. The required success standard for 2009 herbaceous productivity was 135.07 g/m2,(using 13.71 inches precipitation for the x variable). The measured herbaceous production value on the 2002 BRB for 2009 was 190.88 g/m2. As stated previously, noxious species may not count towards revegetation success standards. As long as the herbaceous productivity data did not include any of the noxious species, the herbaceous productivity standard was successful for the 2002 BRB in 2009. Reclamation area 30 was not sampled for bond release application, solely for monitoring, therefore, statistical sample adequacy was not achieved for reclamation area 29. Reclaimed area 30 was reclaimed and seeded in 2006. Only one noxious species, Bromus tectorum (Cheatgrass), was identified in the Reclamation Area 29 vegetative cover data. Removal of the cover contributed by Bromus tectorum found that the measured vegetation cover on Area 30 in 2009 was 47.00% vegetative cover. This value exceeds the calculated 35.69% live vegetative cover for 2009. Area 30 was not sampled to adequacy for herbaceous productivity. The measured value of 189.59 g/m, exceeded the calculated 135.07 g/m2 herbaceous productivity success standard for 2009. 2009 Sampling for Reclamation Area 29: Reclamation Area 29 was reclaimed and reseeded in 2003. This reclaimed area consisting of 8.1 acres was sampled as an individual bond release block (BRB-29). Vegetation Sampling on BRB-29 was conducted August 34, 2009. Sample adequacy was achieved for both the vegetative cover sampling and the herbaceous productivity sampling for BRB-29. The calculated vegetative cover standard for 2009 was 35.69% live vegetative cover. The operator measured total vegetative cover of 61.6%, however, this cover value includes cover from one noxious species, Bromus tectorum. Removal of the noxious species cover contribution results in total vegetative cover of 54.4% LVC. Removal of annual and biennial species in excess of 10% relative cover (24.44% annual biennial relative cover- 10% allowable annual cover=14.44% annual relative cover to subtract) results in allowable live vegetative cover of 39.96%. This adjusted value exceeds the live vegetative cover standard of 35.69% for 2009. Reclamation Area 29 (BRB-29) is considered successful for live vegetative cover for 2009. The calculated herbaceous productivity standard for 2009 was 135.07 g/m2. The operator measured herbaceous production on Reclamation Area 29 (BRB-29) as 258.63 g/m2. This value exceeds the calculated herbaceous productivity standard. The operator needs to assure that noxious species did not contribute to the herbaceous productivity value. Herbaceous productivity is considered to have met the required productivity standard on Reclaimed Area 29. BRB-29 had four perennial grasses with greater than 3% relative cover measured during the 2009 sampling event. These were Sand bluestem, Andropogon hallii, a perennial warm season grass, Blue grama, Bouteloua gracilis, a perennial warm season grass, Prairie Sandreed, Calamovilfa longifolia, a perennial warm season grass, and Indian ricegrass, Oryzopsis hymenoides, a perennial cool season grass. This species composition fulfills the requirement for species composition for BRB-29. No one species exceeded 40% relative cover during the 2009 sampling event. Keenesburg SL5 Memo 3 June 11, 2010