2021-03-31_REVISION - C1982057 (3)

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Cover In 2018, for BRB-5,introduced perennial cool season grasses were the predominate life form,consisting mainly of sheep fescue(Festuca ovina),and intermediate wheatgrass (Thinopyrum intermedium),two species used for grazing. Introduced perennial forb were the next predominate life form consisting mainly of Alfalfa (Medicago sativa),also used for grazing. The predominant cool season native grasses included basin wildrye (Leymus cinereus), and western wheatgrass (Pascopyrum smithi). Noxious weeds were observed at the site but they did not contribute significant amounts of vegetative all-hit cover. Total average all-hit vegetation cover was 64.9%. Allowable all-hit herbaceous vegetation cover was 55.5%after removing excess annual/biennial cover and noxious weeds. Average species density was 36.5 species per 100m2. In 2019, for BRB-5, introduced perennial forbs were the predominant lifeform observed followed by native perennial cool season grasses. Introduced perennial forbs were comprised primarily of alfalfa. Native perennial cool season grasses were comprised primarily of western wheatgrass and basin wildrye. Introduced perennial cool season grasses were predominately comprised of sheep fescue. Noxious weeds were observed at the site but they did not contribute significant amounts of vegetative all-hit cover. Total average all-hit vegetation cover was 81.4%. Allowable all-hit herbaceous vegetation cover was 72.3%. Average species density was 28.9 species per 100m2. For the ERA,the 90% success standard was found to be 37.9%and 38.8%cover in 2018 and 2019 respectively. The Allowable all-hit vegetation cover for both 2018 and 2019 in the BRBS exceeded the success standard, sample adequacy was demonstrated for the reclaimed area and therefore in accordance with Rule 4.15.11(2)(a),revegetation success in term of vegetation cover has been achieved. Production In 2018 in the BRBS the total herbaceous production was found to be 1,862.0 pounds per acre,all of which was allowable. Of this, 876.4 pounds were native perennial cool season grasses, 524.4 pounds were introduced perennial forbs, and 293.8 pounds were introduced perennial cool season grasses. Native perennial forbs (55.2 pounds per acre), introduced annual grasses(43.0 pound per acre),native annual and biennial forbs (37.6 pounds per acre), and introduced annual and biennial forbs(31.6 pounds per acre) contributed similar amounts to production. In 2019, for BRB5,the total herbaceous production was 2,090.5 pounds per acre, all of which was allowable. Of this, 1,182.4 pounds were introduced perennial forbs, 589.0 pounds were native perennial cool season grasses, and 243.5 pounds were native perennial forbs. Introduced annual and biennial forbs (56.8 pounds per acre),native annual and biennial forbs(14.0 pound per acre), and introduced annual grasses(4.8 pounds per acre)also contributed to total production. Ninety percent of the area weighted production standard was 695.5 and 632.9 pounds per acre for 2018 and 2019 respectively. In 2018 and 2019,the BRB-5 allowable herbaceous production exceeded the performance standard but sample adequacy was not achieved. Therefore, CCAI performed a one-sample t- test of the reverse null hypothesis that the total allowable herbaceous production is from the BRB-5 is less than or equal to 90%of the weighted area performance standard derived from the ERA. This hypothesis was rejected in both cases in 2018 and 2019 and therefore the BRB-5 passes the revegetation success standard for production in accordance with Rule 4.15.11(2)(c). Permit Number: C1982057 Page 10 of 15 Phase III