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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-212 Contrast Matrix). Similarly, because of the level of new access road construction (Access Level 2 and 3) and minimal disturbance to shrub vegetation, landscape contrasts would be moderate to weak. Overall, Route Segment NNR-4o would create weak to moderate-weak Project contrasts. For the Overhead Design Option, pulling and tensioning sites would also cause short-term landscape contrasts and structure contrasts. The presence of a helicopter during the stringing of the transmission line conductor wires would cause short-term structure contrasts, potentially disrupting views or scenic vistas (e.g., toward the Cascade Mountains). The temporary structure work areas, turn-around areas, and staging areas would cause low impacts due to the duration of landscape and structure contrasts. Impacts from light sources would not occur because construction would be limited to daylight hours. The potential for glare from the transmission line conductors would be reduced with the use of non-specular conductors (RDF VIS-6). Underground Design Option Structure contrasts created as a result of Route Segment NNR-4u would be limited to the presence of the overhead to underground transition stations located adjacent to I-82 and at the beginning and end of the route segments. In these areas, structure and landscape contrasts would be strong, resulting in strong Project contrasts. Along the underground section of the route segment, contrasts would be the result of duct bank and access grading in steep terrain where underlying soils and geology would be exposed in potentially expansive hillside cut areas. In these areas, sagebrush or rabbitbrush vegetation removal would also increase visual contrasts. Overall, Route Segment NNR-4u would result in moderate-weak to moderate Project contrasts. Scenic Quality Impacts and Development Character Overhead Design Option Scenic quality in the area of the Route Segment NNR-4o is influenced by the presence of the existing Pomona-Wanapum 230 kV transmission line. Because Project contrasts are typically weak to moderate- weak scenic quality impacts would be low to moderate. WSDOT conducted a visual quality evaluation of the I-82 Crossing #2 south of Exit 11 based on the FHWA’s Visual Impact Assessment for Highways methodology. Existing visual quality was rated as 4.83 (high) at the highway crossing. With the implementation of the route segment at this location, the visual quality of the highway in the area of the highway would drop to 4.25 (moderately high). There would be some degradation of visual quality in the area of the transmission towers, but visual impacts would not reach a substantial level (WSDOT 2014). Underground Design Option As with the Overhead Design Option, scenic quality in the area of Route Segment NNR-4u is influenced by the presence of the existing Pomona-Wanapum 230 kV transmission line. However, because of the presence of the overhead to underground transition stations and potentially large areas of cut and fill, moderate to low scenic quality impacts would also result from the route segment. Sensitive Viewer Impacts Overhead Design Option The primary viewers of Route Segment NNR-4o would be travelers using I-82 who would briefly view the route segment as it crosses the interstate at MP 1.2-1.3 adjacent to the existing Pomona-Wanapum 230 kV transmission line. Moderate impacts would result from the crossing structures in the vicinity of the interstate and they would be less apparent and blend in with the existing structures. The implementation of mitigation measures VR-2 and RDF VIS-7 would reduce the visual impact on the residences and