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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-188 The process of photo-simulation began with taking field photographs, documenting viewpoint locations (coordinates) and weather conditions, and matching those photographs with Project area terrain models developed using Microstation. Computer models of the transmission lines and substation were introduced into the terrain model based on preliminary facility layouts developed in ArcView and AutoCAD. The final image is a composite of the 3-dimentional structure modeling and the original photograph. The process ensured that spatial relationships, perspective, proportions, and similar visual attributes were accurate and matched existing landscape conditions. The KOP photographs were taken with a Canon DSLR Rebel XSI 12 megapixel digital camera with an 18 – 55 millimeter zoom lens or a Ricoh 500SE GPS-ready digital camera. The camera was hand held at eye-level (approximately five feet and six inches above the ground). The date, time of day, GPS coordinates (latitude/longitude), and weather conditions were documented. The proposed Project structure types were modeled based on structure standards provided by Pacific Power and assumed undergrounding construction methods provided by POWER Engineers, Inc. (POWER) staff. Final engineering of the proposed transmission line would occur after the environmental analysis phase of the Project is complete and once a final route is chosen. Actual pole locations and configurations may deviate from the simulations shown in Appendix C-4. 4.8.2 Impact Criteria Impacts are created as a result of proposed Project contrast, or change, in viewing conditions or scenic quality, and impacts are measured by the alteration of existing form, line, color and/or texture in the vegetation, landform, and structures (built features, architectural character). Impacts are a product of how changes are viewed (distance, viewing angle) or the change in the inherent qualities of the (man-made or natural) landscape. Impact to viewers depends on the visual sensitivity of the viewer (see Section 3.8.2.4). Visual contrast is the basis on which visual impacts are measured. 4.8.2.1 Contrasts Contrasts range from weak to strong, with resulting impacts based on visibility and distance. For scenic quality, contrast directly affects the inherent scenic quality of the landscape or, conversely, is related to the ability of existing development character to absorb the engineered architectural form/line/color/texture of the proposed Project. The impact analysis for the proposed Project was based on contrast and visibility modeling and the Contrast Rating Worksheets (Form 8400-4) from representative sensitive viewpoints (e.g., KOPs). A contrast model was also used as a basis to assess impacts along the Action Alternative route segments. The contrast model consisted of landscape contrast and structure contrast, which were combined to determine overall Project contrast along the route segments. For the Underground Design Option, landscape contrast was based on the slope of the terrain and land cover crossed by the underground segments. A database of Project contrast was mapped and entered into the GIS for the impact analysis. Project contrast was then compared with proposed Project visibility, scenic quality, or visually dominant development character to determine preliminary impacts. As previously stated, visual assessment considered landform, vegetation, and structure contrast. Landform and vegetation contrast was determined based on the access road disturbance model (as described in Section 2.4.3.2) and existing vegetation and was expressed as an overall landscape contrast (see Table 4.8-1 below). Vegetation or land cover was grouped into visually similar categories (Group 2, Group 3, etc.) based on the visual characteristics of the dominant vegetation such as perennial or annual grassland, sagebrush perennial/annual grassland, or sagebrush dominated. In areas with open water, exposed rock, or disturbed/developed areas it was assumed there would be no vegetation removal and vegetation contrast would not occur. No additional road building would occur on basalt cliffs, in developed areas, or where open water is present (N or No Contrast).