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PROPOSED DECISION - Canadian Strip/Phase II Bond Release <br /> October 1 , 1990 <br /> Page 5 <br /> In summary, since modeling shows that post-mining sediment generation is <br /> less than in the pre-mining situation and since the field observations <br /> document that erosion at the site would not be disruptive to the <br /> post-mining land use, the Division finds that both the '79-'81 reclaim <br /> and the 1987 reclaim at Canadian Strip are eligible for Phase II Bond <br /> Release. <br /> The second condition which must be met for Phase II Bond Release regards <br /> the successful establishment of vegetation, per Rule 3.03.1 (2)(b) . The <br /> Division considers that the vegetative cover standard must be met, as <br /> this parameter relates directly to erosional stability of a site. <br /> Wyoming Fuel Company utilizes a reference area in establishing their <br /> vegetation standards. Rule 4.15.7(2)(c) states that sampling should be <br /> valid at the 90% confidence level with a 0.10 alpha probability on a <br /> one-sided error test. <br /> Sampling was performed by both the Division and Wyoming Fuel in 1989 and <br /> 1990. The Division did not sample the reference area in 1989 and was <br /> unable to verify the results submitted by the operator as part of the <br /> Bond Release request on March 1 , 1990. The Division's 1990 evaluation <br /> confirmed the Wyoming Fuel data from 1989 as shown by the information <br /> found in Table 5; the areas reclaimed between 1979 and 1981 do meet the <br /> vegetative cover standard, while the area reclaimed in 1987 does not. <br /> TABLE 5: Comparison of Cover Sampling Data <br /> CMLRD WYOMING FUEL <br /> Date of Percent Date of Percent <br /> Sampling -Cover" Sampling Cover <br /> 1989 <br /> '79-'81 8/21 /89 27.3% 9/22/89 68.4% <br /> '87 8/21 /89 32% 9/22/89 60% <br /> Reference N.D. N.D. 9/22/89 69.8% <br /> 1990 <br /> '79-'81 8/7-8/90 48% 8/6-8/90 44% <br /> '87 8/7-8/90 40% 8/6-8/90 44% <br /> Reference 8/7-8/90 50.2% 8/6-7/90 57% <br /> Species diversity evaluations were derived from the data recorded as part <br /> of the cover analysis. The species diversity standard found in the <br /> permit application states that standard would be met when there are six <br /> principal species of which three will be cool season grasses, two will be <br /> shrubs and one will be a forb. Cool season grasses will contribute 7% to <br />