2008-06-09_REVISION - C1980007 (3)

Home Browse Search

Chapter 3 Table 3-~ Acres of Riparian Cover Types in Road Disturbance Buffers and Potential Methane Drainage R'ell Locations Alternatives 2 and 3 Cover Types Riparian within Road Buffer Riparian within Methane Drainage Well Locations Marsh <1 0 Willow and alder 8 3 Aspen 1 0 Herbaceous <1 0 Total 10 3 Design criteria stipulate MDW would not be located in ripa~:-ian areas unless specifically authorized. However, if MDW were located in riparian areas, vegetation would be damaged and destroyed and soils disturbed, increasing the potential far erosion and surface water sedimentation. Riparian sites would be reclaimed in the same manner as upland sites. However, due to additional available water, riparian vegetation often recovers faster than adjacent upland vegetation. Furthermore, riparian species would likely recolonize the area rapidly following reclamation due to favorable site conditions for hydrophilic vegetation. Less than one acre of wetland vegetation is located within proposed road corridors and MDW windows (Table 3-8). Due to the limited and sensitive nature of these habitats the proposed action would avoid any impacts on wetland vegetation. Sensitive Plants Surface disturbance from new road construc- tion and MDW installation could affect sensi- tive plants if it happens to occur in the same location as a plant population. Design Criteria state appropriate populations or habitats will be surveyed on asite-specific basis prior to ground disturbance. Colorado tansy-aster has not been documented in the project area, and if encounter would not be impacted by the proposed action. If populations are encountered they would be avoided or other mitigation would be implemented to avoid effects on plants or populations, where possible. Rocky Mountain thistle inay benefit from drilling and associated surface disturbance by the creation of suitable habitat (Panjabi and Anderson 2004). If the species is present near an area of disturbance, it may be able to colonize newly disturbed areas. While this species may be adversely affected by off-road vehicle use or inadvertent targeting of the species as part of a noxious weed control program, these impacts are not likely to occur as a result of the proposed project due to required design criteria (Table 2-1). Surveys for sensitive plants would be conducted in likely habitats before disturbance occurs and populations would be avoided or other mitigation implemented to avoid effects on plants or populations, if possible. During sensitive plant surveys, any occurrence of Rocky Mountain thistle would be flagged and mapped to avoid inadvertent herbicide application during weed treatments. Species identif cation information should also be pro- vided to the weed control agent to further decrease the likelihood of species misidentifi- cation. For these reasons, there will likely be a beneficial impact to this species in the creation of disturbance areas suitable for propagation. Table 3-9 displays the surrunary determination 88 Deer Creek Ventilation Shaft and E Seain Methane Drainage Wells FEIS 1. i-.: i~~ ~ •