2011-08-19_REVISION - C1980001 - Laserfiche WebLink

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Chevron Mining, Inc. Edna Mine: 2011 Weed Management Report • Vegetative cover was measured using 10 -meter transects with 100 point intercepts per transect. The value of each intercept equals 1% of the total cover. • Transect locations throughout the Moffat area were determined by locating a square grid using random number generation. Transects were oriented in a random direction using the second hand of a watch. Total number of transects was determined by satisfying statistical adequacy requirements for the sample population at a 90% confidence interval as described in the permit. Vegetation sampling was conducted on August 4 and 5, 2010 by Chris Keough and Lindsey Brandt of HMI. Eighteen vegetation cover samples were collected in order to obtain statistical adequacy throughout the Moffat area. The results demonstrated that absolute vegetation cover of noxious weeds in the Moffat area was 0.7 %. Relative cover of noxious weeds in the Moffat area was 1.6 %, which is significantly below the 3% maximum level allowed by the DRMS. At the conclusion of sampling, it was noted that a few weed infestations persisted in the lower Moffat area; however, these areas did not reflect the condition of the Moffat area as a whole. This vegetation sampling data was reported to CMI in August 2010. Although 2010 noxious weed management criteria set forth by DRMS was satisfied using approved sampling methods, a final bond release inspection could not be scheduled by DRMS in 2010 to accommodate interested members of the public. As a result, final bond release was delayed into 2011. CMI subsequently contracted HMI in 2011 to continue weed management at the mine: 1) In preparation for the final bond release inspection; and 2) In order to address potential concerns voiced by the public. 2011 Weed Management Prioritization Edna weed management efforts in 2011 were prioritized under the direction of Steve Leach of CMI and Janet Binns of DRMS. In anticipation of a DRMS bond release inspection, an initial evaluation of potential early season weed concerns was made by State of Colorado - licensed Qualified Supervisor Chris Keough of HMI on June 9. At that time, whitetop infestations were found to be a concern across both the West Ridge and Moffat areas, with small populations of Canada thistle and houndstongue beginning to appear sporadically throughout the Moffat area, particularly in the vicinity of Moffat Pond. As a result, HMI and CMI determined that an early season herbicide application would be beneficial in combatting whitetop populations in particular, and the first treatment visit was scheduled for and conducted June 13 through June 16. On June 21, DRMS conducted a bond release inspection at the Edna Mine to determine the extent of remaining noxious weed infestations and prioritize additional 2011 treatments based on their observations and upon public comment received as a result of the inspection. At the inspection, Janet Binns of DRMS identified four remaining areas containing infestations of concern to the State and other interested parties. At the conclusion of the inspection, it was understood by HMI and CMI that a second round of herbicide applications would focus on these remaining areas, and that if treatment of these infestations was deemed successful by DRMS, no further herbicide applications would likely be required. The areas of concern noted by Janet Binns at the inspection included the area immediately surrounding Moffat Pond (perennial pepperweed, houndstongue, Canada thistle), the area immediately east and upslope of Moffat Habitat Management, Inc. 2 August 19, 2011