2021-03-31_REVISION - C1982057 (3)

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Woody Plant Density In 2018,regarding"background" woody plant density, the total density was found to be 819.5 stems per acre. Native shrubs were the dominate contributor, consisting primarily of mountain snowberry (Symphoricarpos rotundifolius), and big sagebrush (Artemisia tridentate). Regarding"volunteer" concentration area density,total density was 2,165.1 stems per acre. The primary species found within this area was mountain snowberry, big sagebrush, Wood's rose (Rosa woodsia), Saskatoon serviceberry (Amelanchier alnifolia)and rubber rabbitbrush (Chrysothamnus nauseosus). In 2019, regarding"background" woody plant density, the total density was found to be 677.9 stems per acre. Native shrubs were the dominate contributor, consisting primarily of mountain snowberry,big sagebrush, and Wood's rose. Regarding"volunteer" concentration area density, total density was 1,296.1 stems per acre. The primary species found within this area was mountain snowberry, big sagebrush, Wood's rose, and Saskatoon serviceberry. The mean woody plant density in BRB5 exceeded 90% of the both Mandatory Standard 1 and 2. However, sample adequacy was not achieved for the background area sampling in either 2018 or 2019. Therefore,reclamation success under Phase III for woody plant density is demonstrated by passing a one- sample t-test of the"reverse null"hypothesis that the woody stem density found in the BRB5 is less than the performance standard. This hypothesis was rejected in both cases in 2018 and 2019 and therefore the BRB-5 passes the revegetation success standard for woody plant density in accordance with Rule 4.15.11(2)(c). It should be noted that CCAI conducted a normality test for the background area sample data and consequently conducted a square root transformation of the data for the success calculations for the hypothesis test. While this normality test and transformations are not addressed in the Rules, it was found that the same successful results would have been achieved using the raw/un-transformed values. In 2018,the mean density in the "volunteer" concentration area of the BRB-5 (2,165.1 stems per acre) exceeded 90%of the mandatory performance standard 2 (900 stems per acre). In 2019,the mean density in the "volunteer" concentration area of the BRB-5 (1,296.1 stems per acre) exceeded 90%of the mandatory performance standard 2 (900 stems per acre). Thus,revegetation success for the WPD mandatory performance standard 2 under Phase III was demonstrated in 2018 and 2019. Given that 75 samples were taken in the BRB5 volunteer concentration woody plant density area during both years, a direct comparison of reclaimed area mean to standard is allowed under Rule 4.15.11(3)(b)(1)). Species Diversity With regard to Mandatory Test A,that no single species comprise greater than 60%relative cover in the BRB5. The most abundant single species,Alfalfa,was 25.8%relative all-hit cover in 2018 and 36.9% relative all-hit cover in 2019, far below the 60%threshold of concern. Mandatory Test A passes for 2018 and 2019 data. For Alternative Test B, a total species density test was conducted for the BRB-5. The probability-adjusted density standard was 23.6 and 22.5 species per 100 in in 2018 and 2019 respectively. The mean total species density for BRB5 was 25.2 and 26.8 species per 100 in in 2018 and 2019 respectively. Since the reclaimed area value was greater than the standard,Alternative Test B is passed for 2018 and 2019 data. Permit Number: C1982057 Page 11 of 15 Phase III