2018-01-03_PERMIT FILE - C1981010 (9)

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5 calculations. If additional samples were needed, these were taken from a pool of additional transects predetermined during the desktop portion of the study. Following clipping, the green weights of the harvested plant materials were taken. These samples were dried in a laboratory drying oven at two different temperatures. To repeat the interpreted historic methods that obtained air-dry weights, plant samples were dried at 50 degrees C for a period of 24 hours and then weighed. Then, in order to comply with the current CDRMS standard, the samples were further dried at a temperature of 105 degrees C until the samples had reached a constant weight of +/- 0.1 of a gram (Rule 4.15.11(1)(b)(ii)). CDRMS has named this drying standard as oven -dry weights. 2.2.3.3 Shrub Density In the 2014 sampling effort, woody stem density was determined in a one meter wide belt along either side of the tape measure. The right-hand side was called Side A and the left-hand side was called Side B. Data collected from each side of the tape were recorded as a single value for each transect, which represented the number of shrubs sampled in the 100 m2 sample plot. These data are reported in the Results Section as to the number of shrubs per 100 m2 as well as the number of shrubs per acre. Woody plants having a single stem, such as big sagebrush, were counted as one living plant. Those species that grow multiple stems, such as black chokecherry, Saskatoon serviceberry and mountain snowberry, were often difficult to distinguish as to the boundaries of individual plants. For such plants the density counts were made on the basis of stems that originate from a common root crown, which follows CDRMS procedures on page 9 of the Vegetation Guideline. 2.2.3.4 Sample Adequacy Calculations For each of the major plant communities, all of the field data were analyzed in terms of "total plant cover" to determine whether sample adequacy was achieved prior to leaving the site being sampled. For production sampling, a minimum of 30 samples were collected and the green plant weight data analyzed to determine whether sample adequacy had been achieved. For shrub density, a minimum of 30 samples were collected and the data analyzed to determine whether sample adequacy had been achieved. In instances where production was not achieved with 30 samples, more transects were sampled. The CDRMS has historically used different statistical guidelines to calculate sample adequacy. Page 15 of the Vegetation Guideline states that "the t table value for a double -tailed t test with infinite degrees of freedom at the 90% confidence interval" or the value of 1.64 should be used. Rule 4.15.10(2) of the Regulations states that the `t -table value for a 1 tailed t-test, n-1 degrees of freedom (infinite degrees of freedom maybe used if n >30'). Page 20 of the Bond Release Guideline states that "the (alpha = 10) t -table value for a single tailed t-test with (n-1) degrees of freedom" is to be used. The bond release guideline was used in this evaluation (the t -value was for a one -tailed t-test at the 90 percent confidence interval). As required by CDRMS's regulations and Vegetation Guideline, it is not always necessary to achieve sample adequacy for vegetation monitoring provided that at least thirty transects have been sampled. As required in Rule 4.15.10, a minimum of 15 cover transects, 30 production transects, and 30 shrub density transects were collected from each vegetation type sampled. As outlined on page 15 of the Vegetation Guideline and as directed during the permit consultation meeting, Ms. Sandy Brown and Mr. Jared Ebert gave verbal approval for TMI to cease sampling after sampling fifty production transects. Notwithstanding this approval and regulatory consent, all of the data collected in this evaluation were analyzed for sample adequacy in order to ascertain whether or not the CDRMS statistical requirements for sample size had been satisfied. The sample adequacy formula found in the regulations was used,