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

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3 the transect location starting points were located in the field using the navigate feature of the GPS unit. The Trimble Model Geo XH GPS unit had a real-time accuracy that located vegetation boundaries and transect locations in the field to within one meter of their true positions. Each transect was oriented using a random compass direction (1° to 360°) assigned to each starting coordinate point. Then a 50 -meter long tape measure was laid -out in the specified direction from the starting point. All transects were kept within the assigned plant community polygons. If the original orientation and start point resulted in a transect crossing a vegetation unit boundary, then the transect was backed -up in the opposite direction until the transect was fully within the assigned area. Where the 50 -meter tape could not be placed within a narrow vegetation polygon without crossing a boundary, then the transect was reoriented by 90° at the observation point immediately before intersection with the boundary line to ensure that the entire transect was located within the specified sampling area. The locations of the cover, production and shrub density transects sampled in this evaluation are shown on Map 48A. The details pertaining to each vegetation community sampled are described in the following sections with the results provided in Section 3. 2.2.2 Field Sampling Dates All 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 1 (PR -7 Mine Expansion Area - Plant Species List) lists all the plant species encountered during field sampling. The field mapping of the Wetland Plant Community began on October 23, 2013. The formal wetland delineation employing USACE protocols and vegetation sampling followed and finished on November 18, 2013. 2.2.3 Field Sampling Methods TMI proposes to continue to use the currently approved revegetation technical standards in its permit for the PR -7 Mine Expansion Area. Therefore, the field data collected in 2014 followed methodologies similar to those used to collect the historic baseline vegetation data. This allowed for statistical comparison between the historic data and current data. Because the original permit standards were used, there are some minor differences in the sampling and analysis methodologies used here from those currently recommended by the CDRMS. The historic TMI data (1979-1985) were collected using an optical point bar, which is similar to the 10 - point frame method used in this survey. Examination of the historic Trapper Mine baseline vegetation data in Permit Tables 2.3-2, 2.3-4, and 2.3-6 revealed that the 1979 plant cover data were collected and summarized by total plant cover. The 1980 to 1985 plant cover data were summarized on the basis of percent total herbaceous cover, with no data being reported for percent total plant cover or relative cover cataloged by individual species; plant life form; or percent litter, bare ground, or rock. Current production sampling methodologies were similar to those used in the past, except the 1979 production data for the Big Sagebrush - Grass Range Site C plant community included "all current annual growth" and included shrubs. In contrast, the production data from 1980 to 1985 included "current annual growth" (CAG) of only herbaceous species, which also included annuals, biennials, and noxious weeds. All the historic production data collected from 1979 to 1985 were dried in a drying oven at a temperature of 50°C for a period of 24 hours, which was termed air-dry weights.