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These interim revegetation monitoring data document that the existing Permit revegetation <br />success standards with respect to woody plant density and the warm season species diversity <br />standards associated with this mine site are contrary with the requirements of Rule 4.15.1(1) <br />which requires that the operator "establish on all affect land a diverse, effective, and permanent <br />vegetative cover of the same seasonal variety native to the area of disturbed land that support the <br />approved post- mining land use." No where can it be found in the regulations or in the <br />Vegetation Guideline where it is required that the revegetation success standards, i.e. warm <br />species diversity must be several orders of magnitude higher than what exists on the adjacent <br />undisturbed lands. The Vegetation Guideline clearly states on page 11 that the revegetation <br />success standards must be "appropriate and attainable... ". Both the woody plant density and the <br />warm season species diversity standards associated with this mine site are virtually impossible to <br />achieve and under a separate cover IME will make recommendations to EFCI to submit a permit <br />revision to modify these revegetation success standards. <br />The owners of the Vento property, have expressed concerns about the apparent dominance of <br />Rubber Rabbitbrush on the reclaimed areas on their property. Upon comparing the vegetation <br />monitoring data collected in 2006 with that obtained in the 2010 monitoring effort, would appear <br />to document the validity of the observations they have made. In 2006, Rubber Rabbitbrush <br />cover on their property averaged 0.93 percent total plant cover and accounted for 2.19 percent of <br />the total relative cover of the reseeded vegetation on their property. In 2010, these values were <br />found to be 4.20 percent and 6.97 percent respectively, which would seemingly suggest that <br />Rubber Rabbitbrush is increasing in abundance on their lands. With respect to shrub density, in <br />2006, this shrub averaged 7.33 plants per 100 m in 2006 and 5.70 plants per 100 m in 2010. <br />Therefore, to test this assumption, we performed a detailed evaluated of the data from the 2006 <br />and 2010 vegetation monitoring efforts. <br />One parameter used in the field of plant ecology to measure dominance is a "frequency <br />analysis." This parameter is defined as the percentage times a given plant occurs in the sample <br />population. In 2006, this plant occurred in four of the 15 cover transects on the Vento <br />reclamation and thus had a frequency of 26.67 percent. With respect to the shrub density <br />transects in 2006, this plant was encountered in 16 of the 30 density transects and thus had a <br />frequency of 53.33 percent. In 2010 this plant occurred in 2 of the 10 cover transects and thus <br />had a frequency of 20 percent. With respect to shrub density in 2010, this plant was encountered <br />in 5 of the 10 density transects and thus had a frequency of 50 percent. Upon comparing the <br />frequency data of this plant in 2006 as compared to 2010, there is no evidence that this plant is <br />increasing and it fact these data suggest that there is a slight decrease in the frequency of this <br />plant. <br />Another means of evaluating the similarity of plant cover, as detailed in the DRMS regulations, <br />Vegetation Guideline and Bond Release Guideline, is to use the "t- test" statistical comparison <br />which can be used to compare the mean cover of this plant using the 2006 data as compared to <br />the 2010 data. A "t- test" comparison of these data resulted in a t, value of 0.4177. The <br />corresponding t, or tabular t value is 1.711. Since the t or tabular t value is greater than the <br />corresponding t value it can be concluded that there is no statistical difference in the cover of <br />Rubber Rabbitbrush between the 2006 and 2010 sample periods. Therefore, it can be concluded <br />15 <br />