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noxious weed species in the Moffat area measured 0.7 %. Relative cover was determined by <br />dividing the vegetative cover of the species of concern by the total vegetative cover value of <br />all species measured. Relative cover of all noxious species measured in the August 2010 <br />vegetation sampling in the Moffat area was 1.6 %. Total Vegetative cover in the Moffat area <br />in 2010 was 42.0 %. Sampling was conducted to statistical adequacy. The Division <br />guidelines (Guideline Regarding Selected Coal Mine Bond Release Issues, dated April 18, <br />1995) identified 3% relative cover attributed to noxious weed species as the level of concern. <br />Chevron measurement of 1.6% relative cover attributed by all noxious weed species <br />encountered is acceptable to the Division. The species encountered in the 2010 sampling <br />effort were; Canada thistle, Musk thistle, houndstongue, and Perennial pepperweed. <br />Although Chevron Mining, Inc. had achieved the required weed management success in <br />2010, the operator conducted additional weed control efforts in 2011 in accordance with <br />Routt County Weed Program recommendations and to address landowners continued <br />concerns. <br />Post - Mining Land Use <br />The post- mining land use for the Edna Mine is rangeland for enhanced domestic livestock <br />grazing and wildlife habitat. The reclaimed lands have vegetative cover composed of a <br />variety of grasses, forbs, and woody shrubs. The seasonality and forage characteristics of the <br />vegetative species appear suitable for the approved post- mining land use. No significant <br />weed problems or bare areas were found. Weed patches identified during inspections have <br />been addressed by the operator and do not appear to be problematic. <br />The revegetation success standards were based on what would be necessary for the land to <br />properly function as grazing and wildlife habitat. Based on the achievement of the <br />requirements, the Division finds that the revegetation on the Edna Mine reclaimed areas is <br />capable of supporting the approved post- mining land use. <br />On August 22, 2011, WWC Engineering, for Chevron Mining, Inc., provided follow up <br />documentation and photos demonstrating that repairs to the North road had been completed. <br />Division inspection on September 19, 2011, confirmed that the work had been satisfactorily <br />completed. <br />Evaluation of Hydrologic Impacts Required by Section 3.03.2(2) <br />Rule 3.03.2(2) requires the Division to evaluate hydrologic impacts prior to releasing <br />reclamation liability. This evaluation must consider whether pollution of surface or <br />subsurface water is occurring and the probability of future occurrence of such pollution. The <br />Division's evaluation is summarized below. <br />Ground water in the Trout Creek alluvium, on the west side of the mine, is the only ground <br />water that could be adversely affected by the Edna Mine. Bedrock aquifers that abut spoil <br />backfill are likely to impermeable too transmit leachate. Chevron Mining Inc. has <br />monitored alluvial water quality in two downstream alluvial wells, TR -3 and TR -4. Data <br />Edna Mine Page 22 April 12, 2013 <br />Phase II. and III Bond Release <br />