2020-03-24_PERMIT FILE - C1981019A (2)

Home Browse Search

RULE 2 PERMITS 4. Digital 1.5 meter -resolution true color remote sensing imgery exposed in the summer of 2002; and 5. Digital 0.5 -meter resolution color -infrared remote sensing imagery exposed in September of 2005 As indicated above, revision of the vegetation community mapping within the study area was deemed appropriate. In this regard, a digital copy of true color aerial imagery (exposed during the summer months of 2002) was obtained and utilized to refine previous community delineations. Stratification of communities was based on identifiable dominant floral species and / or land use -related characteristics. The delineated natural communities were 1) Mountain Shrub (both xeric and mesic subtypes), 2) Sagebrush (both xeric and mesic subtypes), 3) Aspen Woodland, 4) Juniper Scrub, 5) Grassland, and 6) Bottomland. Wetlands were not separately delineated due to their extremely small footprint and the fact that they are administered separately under the Clean Water Act by the Corps of Engineers. Identified wetlands areas that may be affected by mining activities will be delineated and mapped for Section 404 permitting prior to disturbance. The land use categories of cropland and stock tanks are also delineated but are not considered natural vegetation communities. Boundary interpretations were compared to aerial imagery. Photographic diagnostic information for each vegetation community or land use type (unique community signatures) was identified during field work at multiple ground verification points and then utilized to adjust final community boundary delineations. Sample Layout - The sample layout protocol for the 2005 grassland community evaluation is a procedure designed to better account for the heterogeneous expression of vegetation cover while precluding bias in the sample site selection process. By design, the procedure is initiated randomly, and thereafter, samples are located in a systematic manner, along grid coordinates spaced at fixed distances (Figure 2.04.10-2). In this manner, "representation" from across each delineation is "forced" rather than risking the chance that significant pockets are entirely missed, or overemphasized as often occurs with simple random sampling. The procedure for sample location within the grassland community and corresponding reference areas (two) occurred as follows. First, a systematic grid (40 ft. x 40 ft., 50 ft. x 50 ft., or 75 ft. x 75 ft.) was selected to provide at least 20 coordinate intersections that could be used for sample sites. Second, a scaled, computer-generated representation of the selected grid was overlain on a computer-generated map of the area. Third, utilizing a hand held surveying compass and hip -chain (or pacing techniques) all sample points were located in the field and flagged. Locations of all sample sites used in 2005 sampling efforts are indicated on Map 4B. Sample layout was based on preliminary delineations; therefore, some inconsistencies can be noted in comparison to final delineations. Two reference areas are indicated for the grassland community because of substantial parametric differences between lower versus ridgetop expressions of this type. The only area that could be used for reference at lower elevation is immediately adjacent to an improved pasture that exhibits elevated cover and production values. Because of proximity to this pasture, many of the improved pasture grass species (e.g., intermediate wheatgrass) have heavily invaded thereby artificially increasing cover and production values of the area. These elevated values would preclude statistical validation of this single area as an appropriate revegetation performance target. The second reference location is just external and along the southernmost ridgeline of the study area. This expression of grassland provides more limited cover and especially production values, and would also preclude statistical validation of the singular area as an appropriate revegetation performance target because of depressed values. However, left with no other alternatives, it was the judgment of the field crew to sample both areas and utilize average values from these two sites for statistical comparison with the grassland community. Once a selected grid point was located in the field, ground cover sampling transects were always oriented in the direction of the next site to be physically sampled to further limit any potential bias while South Taylor/Lower Wilson — Rule 2, Page 49 Revision Date: 4/7/17 Revision No.: RN -07