2018-01-03_PERMIT FILE - C1981010A (12)

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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, then more transects were sampled. 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, CDRMS gave verbal approval 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, with a precision of 0.10 used for cover and production and a precision of 0.15 used for shrub density. The plant cover data as collected yields a value of absolute cover (number of counts of each species per transect). These cover data were converted into percent composition or relative plant cover by dividing the absolute cover values by the total amount of plant cover encountered in the transect. The species diversity standard being proposed for the PR -7 Mine Expansion Area is that currently approved in the Trapper Mine Permit where species diversity is determined by the dominant species sampled in the plant community. Appendix D -VI contains additional detailed information on selection of transect locations and field sampling methods. Noxious Weeds: Based on CDRMS regulations and the lack of a current County -specific noxious weed list for Moffat County, noxious weeds evaluated in the 2014 survey are those species found on the Colorado Department of Agriculture website at: http://www.colorado.gov/cs/Satellite?c=Pape&cid as accessed on 10 October 2014, which has been assembled per the provisions of the Colorado Weed Management Act. This site contains three lists of noxious weeds, List A, List B and List C. All species on the three lists were considered noxious weeds during the survey. Rare and Endangered Plant Species: The potential presence of rare and endangered plants was determined based upon a careful review of the existing scientific literature and consultation with the CDRMS and the Colorado Division of Parks and Wildlife (CPW). The most comprehensive treatment of this topic is found on the website of the Colorado Natural Heritage Program found at www.cnhp.colostate.edu, which contains the Colorado Rare Plant Field Guide published in 1999 and an update called the Colorado Rare Plant Field Guide - 2002 Update. These documents were used to determine the presence or absence of rare and endangered plant species during the field survey. 2.3.6.2 2014 Field Work Fieldwork for the vegetation sampling was conducted between August 9 and September 15, 2014. At the time of the field sampling, all plants were actively growing, and sampling was performed close to the seasonal peak of plant cover and above ground production. A total of 129 plant species were identified in the 158 cover transects and the 105 shrub density transects sampled in this evaluation. Table 2.3-25, PR -7 Mine Expansion Area - Plant Species List, shows the plant species encountered during field sampling. 2-122b Revision: P/? -08 Approved: