Vantage to Pomona FEIS Index 34 - Laserfiche WebLink

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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-28 and was not surveyed (Table 3.2-3). As not all land within the route segment corridor was surveyed, impacts could occur to special status plant species. Long-term disturbance would occur to potential habitat for special status plants and include 12.2 acres of suitable, 6.8 acres of marginal, and 6.7 acres unsuitable habitat. RDFs described above for Route Segment 1a/NNR-1 would also be implemented during construction and maintenance of Route Segment 3c to minimize impacts to special status plants. WNHP data indicates that Route Segment 3c intersects a WNHP Priority Ecosystem, Intermountain Basins Active and Stabilized Dune two times. Approximately 2.7 miles of the Route Segment 3c crosses this plant community just north of the Columbia River. The second occurrence, 0.2 mile, is located in the Saddle Mountains. Impacts to this WNHP Priority Ecosystem would occur through disturbance and vegetation removal associated construction. Impacts would be reduced by: closing access roads, where not needed; implementing noxious weed control, and minimizing blading and disturbance to plant communities. With the implementation of RDFs, impacts to special status plant species, potential suitable habitat, and WNHP priority ecosystems are anticipated to include 8.0 miles of no identifiable, 2.8 miles of low impacts, and 14.5 miles of moderate impacts. Awned Halfchaff Sedge Refer to Route Segment 2d for information on awned halfchaff sedge. WNHP data indicate that awned halfchaff sedge intersects Route Segment 3c for 0.1 mile. This location includes a large buffer; therefore, it is difficult to accurately determine whether this occurrence truly intersect the ROW corridor. Known occurrences of awned halfchaff sedge are within wetlands along the Columbia River. Within the proposed Project, wetlands and the area immediately adjacent to the Columbia River would be avoided. Nearly all potential habitat on federal and state lands was surveyed, so it is unlikely awned halfchaff sedge occurs in Route Segment 3c. With the implementation of RDFs described above and the assumption that occurrences would be spanned and avoided, Project construction, operation, and maintenance activities could impact individuals or habitat (moderate impact), but would not contribute a trend toward federal listing. Columbia Milkvetch Refer to Route Segment 2b for information on Columbia milkvetch. WNHP data indicate that Columbia milkvetch occurrences intersect Route Segment 3c for 1.6 miles. These locations include large buffers; therefore, it is difficult to accurately determine whether these occurrences truly intersect the ROW corridor. Direct impacts and RDFs that would be implemented to minimize impacts to potential occurrences Columbia milkvetch are similar to those described above for Route Segment 2b. Nearly all potential habitat on federal and state lands was surveyed, so it is unlikely Columbia milkvetch sedge occurs in Route Segment 3c. With the implementation of RDFs described above and the assumption that occurrences would be spanned and avoided, Project construction, operation, and maintenance activities could impact individuals or habitat (moderate impact), but would not contribute a trend toward federal listing. Gray Cryptantha Refer to Route Segment 3b for information on gray cryptantha. WHHP data indicates that gray cryptantha occurrences intersect Route Segment 3c for 2.9 miles. These locations include large buffers; therefore, it is difficult to accurately determine whether these occurrences truly intersect the ROW corridor. Impacts from the proposed Project are similar to those described above for Route Segment 3b. Nearly all potential habitat on federal and state lands was surveyed, so it is unlikely gray cryptantha occurs in Route Segment 3c. With the implementation of RDFs described above and the assumption that potential occurrences would be spanned and avoided, Project construction, operation, and maintenance activities could impact individuals or habitat (moderate impact), but would not contribute a trend toward federal listing.