SECTION 4.0

ENVIRONMENTAL SETTING, IMPACTS, AND MITIGATION

---

PROPOSED PROJECT

4.13  VISUAL RESOURCES/AESTHETICS

This section addresses the visual resources environmental baseline conditions and the potential for the proposed Trans Bay Cable Project to cause significant impacts on those resources in the Project study area. This assessment was conducted in conformance and compliance with California Environmental Quality Act (CEQA) guidelines and documentation requirements.

4.13.1  Environmental Setting

4.13.1.1  Concepts and Terminology

The concepts and terminology that comprise this visual resources analysis for this proposed Project, as well as the essential Project elements that are evaluated, are described below.

The visual resources of a given area consist of the landforms, vegetation, water features, and cultural modifications (physical changes caused by human activities) that impart an overall visual impression of the area landscape. A number of factors are considered in the evaluation of a landscape's visual resources and of the potential for one or more visual impacts to occur, including visual quality, viewer sensitivity, landscape visibility, and viewer exposure. Each of these factors is generally expressed as low, moderate, or high as discussed below.

4.13.1.1.1  Visual Quality. Visual Quality is a measure of the overall impression or appeal of an area as determined by the particular landscape characteristics such as landforms, rock forms, water features and vegetation patterns, as well as associated public values. The attributes of variety, vividness, coherence, uniqueness, harmony, and pattern contribute to the visual quality classifications of indistinctive (low), common (moderate), and distinctive (high). Visual quality is studied as a point of reference to assess whether a given project would appear compatible with the established features of the setting or would contrast noticeably and unfavorably with them. A landscape's ability to accept alteration without diminishment of visual quality (or creation of visual contrast) is referred to as "Visual Absorption Capability."

4.13.1.1.2  Viewer Sensitivity. Viewer Sensitivity addresses the level of interest or concern of viewers regarding an area's visual resources and is closely associated with viewers' expectations for the area. Viewer sensitivity reflects the importance placed on a given landscape based on the human perceptions of the intrinsic beauty of the existing landforms, rock forms, water features, vegetation patterns, and even cultural features.

4.13.1.1.3  Landscape Visibility. Landscape Visibility describes the accessibility of the landscape to viewers, referring to one's ability to see and perceive the landscape. Landscape visibility can be a function of several interconnected considerations, including proximity to viewing point, degree of discernible detail, seasonal variations (fog and haze can obscure landscapes), time of day, and presence or absence of screening features such as landforms, vegetation, and/or built structures.

4.13.1.1.4  Viewer Exposure. Viewer Exposure describes the degree to which viewers are exposed to views of the landscape. Viewer exposure considers the number of viewers, the duration of view, and the proximity of viewers to the subject landscape. Although a landscape may have highly scenic qualities, it may be remote and receive relatively few visitors, and, thus, have a low degree of viewer exposure. The same may be true if a subject landscape or project is situated in proximity to a major road or highway utilized by a substantial number of motorists. Further, if the rate of travel speed on the roadway is high and viewing times are brief, or if the landscape is partially screened by vegetation or other features, this will also affect the exposure factor. It is the subject area's proximity to viewers or distance zone that is of particular importance in determining viewer exposure. Landscapes are generally subdivided into three or four distance zones based on relative visibility from travel routes or observation points. Distance zones typically include foreground, middleground and background. The actual number of zones and distance assigned to each zone is dependent on the existing terrain characteristics and public policy and is often determined on a project-by-project basis.

4.13.1.1.5  Visual Impact Susceptibility. Visual Impact Susceptibility is a concluding assessment as to the degree of probability that a given landscape will demonstrate a noticeable visual impact with project implementation. Visual impact susceptibility is derived from a comparison of existing visual quality, viewer sensitivity, landscape visibility, and viewer exposure.

4.13.1.1.6  Adverse Visual Impact. An adverse visual impact occurs within a public view when: 1) an action perceptibly changes existing features of the physical environment so that they no longer appear to be characteristic of the subject locality or region; 2) an action introduces new features to the physical environment that are perceptibly uncharacteristic of the region and/or locale; or 3) aesthetic features of the landscape become less visible (e.g., partially or totally blocked from view) or are removed. Changes that seem uncharacteristic are those that appear out of place, discordant, or distracting. The degree of the visual impact depends upon how noticeable the adverse change may be. The noticeability of a visual impact is a function of project features, context, and viewing conditions (angle of view, distance, and primary viewing directions).

The key factors for considerations in determining the degree of visual impacts or Visual Impact Severity are visual contrast, project dominance, and view impairment.

4.13.1.1.7  Visual Contrast. Visual Contrast evaluates a potential project's or activity's consistency with the visual elements of form, line, color, and texture already established in the landscape. Other elements that are considered in evaluating visual contrast include the degree of natural screening by vegetation and landforms, placement of structures relative to existing vegetation and landforms, distance from the point of observation, and relative size or scale. Generally, visual contrast inversely correlates with visual absorption capability.

4.13.1.1.8  Project Dominance. Project Dominance refers to the project's relationship to other visible landscape components in terms of vertical and horizontal extent. A project's scale and spatial relationship to the existing landscape can be categorized as subordinate, co-dominant, or dominant.

4.13.1.1.9  View Impairment. View Impairment refers to the extent to which a project's scale and position results in the blockage of higher quality visual elements by lower quality elements.

4.13.1.1.10 Key Observation Points. Key Observation Points (KOPs) are locations selected to be representative of the most critical locations from which the project will be seen. KOPs are often selected in an effort to evaluate impacts on visual resources with various levels of sensitivity, in different landscape types and terrain, and from various vantages. Typical KOP locations include: 1) along major or significant travel corridors; 2) at key vista points; 3) in proximity to residential uses; and 4) at significant recreation areas.

4.13.1.2  Methodology Overview

Baseline data collection was initiated with a review of the Project description as well as other relevant documents from the cities of San Francisco and Pittsburg. A field reconnaissance was undertaken to gain familiarity with the existing landscape setting, visual resource issues of concern, including sensitive land uses adjacent to or crossed by Project components, and the characteristics of the proposed Project sites.

The field reconnaissance was conducted to establish specific KOPs in August of 2005. KOPs are generally selected for one or two reasons: 1) the location provides representative views of the landscape along a specific route segment or in a general region of interest; and/or 2) the viewpoint effectively captures the presence or absence of a potentially significant Project impact in the location. KOPs are typically established in locations that provide high visibility to a relatively large number of viewers and/or sensitive viewing locations such as residential areas, recreation areas, and vista points. These key observation points are identified in detail under the section which assesses potential Project impacts below.

Following completion of the baseline data review, field reconnaissance, and verification of locations for specific study, photographic field studies were undertaken. These studies consisted of viewing the Project landscapes to the extent feasible from public roads and other vantage points to develop an overall assessment of the landscape characteristics and the potential for Project impacts. Photographs were taken to both record the existing context of the major Project components and provide baseline photographs, which were utilized for preparing simulations of the Project and the analysis of potential impacts. All photographs were taken with a lens that is the equivalent to the view seen by the human eye; i.e., neither telephoto nor wide angle.

A description of the existing landscape characteristics and sensitivity was compiled and included notes on the existing visual quality, known viewer sensitivities, landscape visibility, visible evidence of historical and cultural influence and the urban landscape, as well as viewer exposure. The evaluation of viewer exposure also included qualitative notations on potential numbers of viewers, distance zones, and duration of views.

Based on the above factors, an overall visual impact susceptibility rating was determined for each KOP. The proposed Project was then evaluated based upon the simulations and the potential visual resource impacts were determined.

4.13.1.2.1  Project Setting.

San Francisco HWC Converter Station. The proposed San Francisco HWC Converter Station would occupy a 5.6-acre site on 23^rd Street just south of the existing Mirant Power Plant. The proposed site currently has three structures that would need to be demolished for Project implementation.

The KOPs selected for this assessment in San Francisco are shown on Map 4.13-1.

The San Francisco HWC Converter Station site is generally visible from Illinois Street when viewing down either 24^th or 25^th Street within the context of the existing Mirant Power Plant and the adjacent PG&E substation (see Context Photo 1, Figure 4.13-1). This is an existing industrial area both in terms of the visual context and the type of traffic traversing the area. The converter station site is also visible from the Potrero housing projects approximately 0.5 mile to the west. While the facility would be visible from a more birds-eye point view, again it would be seen in the context of the larger industrial activity of the area and the primary focus of any viewer would be toward San Francisco Bay in the background (see Photo 2, Figure 4.13-1). The third viewing area is from Warm Water Cove Park which is located directly south of the San Francisco HWC Converter Station site. Existing views from this area are toward the Bay to the east and the existing industrial structures to the north and south. In this context, the existing buildings to the north would be demolished and replaced by the proposed San Francisco HWC Converter Station (see Context Photo 3, Figure 4.13-2). The onshore AC cable connections would be from the proposed converter station site to the existing PG&E Potrero substation and would not involve significant visual disturbance to this area. Similarly, the offshore HVDC cable connection would be underground from the proposed HWC site into San Francisco Bay and would not involve significant areas of additional disturbance. The proposed laydown area (Western Pacific site) is currently used for truck parking and would not require any construction that would affect the visual character of the area.

Visual Quality. The proposed San Francisco HWC Converter Station site lacks visual coherence and harmony. While some of the structures may be interesting as being old, the general atmosphere is visually cluttered by the juxtaposition of materials, graffiti, uneven pavement, and overhead wires. There are no immediate natural landforms except for the water of Warm Water Cove which is degraded by debris, decaying docks and industrial fences. Moreover, San Francisco Bay does not play a significant visual role when viewing the site from adjacent roads.

The visual quality of the site is classified as Low.

Viewer Sensitivity. This concern may also be categorized as the reason people would visit the area. In this case the area is industrial. Those that work there would have low expectations of the area in terms of its scenic content. City of San Francisco traffic counts along Illinois Street taken in September 2003 at 22^nd Street show an Average Daily Traffic (ADT) of 2,285 trips per day. The duration of travelers' view of the site would range in the area of 5 seconds given the distance from Illinois Street, and the view would not be in the primary cone of vision for those traveling along Illinois Street. Warm Water Cove Park users may be there in part for the view of the water. However, the converter station site does not really affect views of the cove or Bay. Given the overall context, viewer sensitivity is rated Low.

In addition to travelers, there are those that live in trailers parked along some of the streets or in homeless encampments. They may be there for reasons other than the aesthetic properties intrinsic to the area. In addition to those living and working in the immediate area, there are those residents living in the housing project on Potrero Hill. Here the view is more expansive and does include San Francisco Bay (Photo 2, Figure 4.13-1). For these residents, the sensitivity level would be Moderate, not as high as other portions of San Francisco with views of the Bay unaffected by heavy industrial structures in the foreground.

The overall viewer sensitivity level is classified as Low to Moderate.

Therefore, the visual susceptibility index (meaning the probability that a given landscape will demonstrate a noticeable visual impact with project implementation) is Low. Put another way, any proposed facility would have a low probability of disrupting the existing visual resources of the area as seen from roads and public places.

4.13.1.2.2  Pittsburg Standard Oil Converter Station. The proposed Pittsburg Standard Oil Converter Station site encompasses 7.5 acres adjacent to a developed industrial area of Pittsburg to the north and west. One quarter mile to the south is the Pittsburg-Antioch Highway, and there is intervening open space to the east before a continuation of the industrial development, including the Delta Energy Center power plant and the Delta Diablo Wastewater Treatment Facility. Immediately north of the site is a mainline of the Burlington Northern Santa Fe (BNSF) Railroad and the Dow Chemical facility. To the west of the site are several material storage/trucking sites and then a steel fabrication plant. The public views of the area are limited to those from the Pittsburg-Antioch Highway.

The KOPs selected for this assessment in Pittsburg are shown on Map 4.13-2.

The proposed onshore AC/DC transmission line connections are from the proposed Standard Oil site to New York Slough via a diagonal HDD bore to an existing paved road south of the BNSF right-of-way (ROW) until the line turns 90 degrees north along another existing access road for approximately 0.5 mile to the slough. This latter portion of the route is adjacent to vegetated lowland amid a larger open space to the east. The proposed laydown area is north of the converter station site and would not require any construction activities that would permanently affect the visual character of the area.

An alternative construction laydown area is proposed in the open area approximately 1,500 feet east of the proposed converter station and 800 feet north of the Pittsburg-Antioch Highway. While visible from the highway, the site is flat and has few distinguishing characteristics. The alternative construction laydown area was previously used as a laydown area where the Delta Energy Center was constructed.

Visual Quality. While this area does contain some undeveloped land, the general surrounding context is one of heavy industry with power plants, sewage treatment facilities, railroad, and the Dow Chemical facility all visible in the area. Other than Kirker Creek/Dowest Slough, there are no significant natural features remaining adjacent to the proposed Standard Oil site. No major visible vegetation components are associated with Kirker Creek, which is essentially in a channel not readily visible from any adjacent public place or road. While there are some trees and shrubs adjacent to the proposed site, which may provide screening (see Photo 4 and 5, Figure 4.13-3), they do not change the overall visual effect of the industrial area in the background and a relatively undistinguished plane in the foreground.

The visual quality of the proposed AC/DC cable route once it leaves the existing road south of the BNSF ROW (Photo 6, Figure 4.13-4) and turns north toward New York Slough does become more defined with larger cottonwood trees and native plants in the midground (see Photo 7, Figure 4.13-4). However, this area is still predominantly industrial and relatively unremarkable in character.

The visual quality of the proposed access road from the proposed Pittsburg Standard Oil Converter Station site to the Pittsburg-Antioch Highway, including the proposed bridge over Kirker Creek, is also classified as Moderate-Low. The visual quality of the alternative access road (existing road between Standard Oil site and Loveridge Road) is classified as Low.

In summary, the visual quality for the proposed Pittsburg Standard Oil Converter Station site, the proposed laydown area, the alternative laydown area, the AC/DC transmission corridor, and the proposed and alternative access roads is classified Moderate-Low.

Viewer Sensitivity. Public views of the Pittsburg Standard Oil Converter Station site are limited to those from the Pittsburg-Antioch Highway. Travelers along this portion of the route are primarily those working or doing business in the area. It is not a scenic highway. Further views of the Standard Oil site would be relatively long since the site would be visible to westbound travelers for over a mile, which converts to about 1.25 minutes at the designated speed limit of 50 mph.

View sensitivity is classified as Moderate because of the large number of viewers and the long duration of the view even though viewer expectations would be relatively low.

Therefore, the visual susceptibility index is Moderate-Low, meaning any proposed facility would have a moderate/low probability of disrupting the existing visual resources of the area as seen from roads and public places.

4.13.1.2.3  Offshore DC Cable Route. Other than the points at which the cable comes ashore, which are analyzed under the discussion of the onshore facilities, the route of the cable would be totally under water except for the construction period. There would be no landscape that needs discussion under the visual resources analysis.

4.13.2  Regulatory Setting

4.13.2.1  Federal/State

From the visual resources perspective, there are no specific regulations by federal or state agencies that apply with the exception of CEQA.

4.13.2.2  Local

Locally several zoning and height limitations may apply. The overall applicability of various visual resource-related laws, ordinances, regulations, and standards is presented in
Table 4.13-1. In summary, those of relevance are summarized below.

4.13.2.2.1  City of San Francisco. The proposed San Francisco HWC Converter Station Site is zoned M-2 with certain height restrictions as outlined in the 40-X bulk district. However, the project is exempt from these restrictions under section 260 (b) (1) (M).

4.13.2.2.2  City of Pittsburg. The proposed Pittsburg Standard Oil Converter Station site is zoned IG (General Industrial) with a 50-foot height limitation. "An increase over the maximum height allowance is allowed in the IL and IG districts equal to the number of additional feet the structure is set back from each property line beyond the minimum yard requirements up to a maximum of 75 feet. To be entitled to additional height, the building or structure setback must exceed the minimum on all sides." Title 18 Zoning Ordinance, Chapter 18.54 Industrial Districts. Additionally, Pittsburg Municipal Code, Section 18.54.020 states, "All projects require Design Review" (Chapter 18.36).

4.13.3  Environmental Impacts

The proposed onshore AC/DC cable routes in San Francisco are planned to be installed underground and would not result in substantial visual impacts. An alternate overhead AC transmission line has the potential for visual impacts, and is addressed later in this section. The proposed onshore DC cable routes in Pittsburg are also planned to be installed underground. A portion of the proposed AC cable route in Pittsburg for the Standard Oil Converter Station would be installed on 75-foot-tall overhead transmission structures (refer to Figure A.3-22 in Appendix A) between the BNSF ROW and New York Slough. The segment of proposed overhead 230kV line is located approximately 0.5 to 1.0 mile north of the closest public access (Pittsburg-Antioch Highway). Due to their remote location and distance from public view, no substantial visual effects would be expected. The proposed onshore AC/DC cable routes are not assessed further in this analysis. The proposed temporary use of the proposed and/or alternative construction laydown areas in San Francisco and Pittsburg would all involve previously disturbed sites and no long-term visual effects would result from the use of these sites. Accordingly, these laydown sites are not addressed further in this analysis.

TABLE 4.13-1
POTENTIALLY APPLICABLE VISUAL RESOURCE-RELATED
LAWS, ORDINANCES, REGULATIONS, AND STANDARDS (LORS)

4.13.3.1  Thresholds of Significance

The Environmental Setting presented above assesses the susceptibility of each site to potential impacts that might be generated by a Project. In this section, the applicant-proposed design is simulated into the baseline photographs.

The Impact Severity of the project from each KOP is then determined based upon the following criteria which are based in CEQA Appendix G or local criteria. Impacts would be considered significant if they would:

• Block a scenic vista

• Dominate the view or become obtrusive in the scene

• Be out of character with the adjacent landscape whether it is urban or rural

• Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area

The response to these criteria determines the Impact Severity of a project. As with Impact Susceptibility, the Impact Severity of a project is rated Low, Medium or High. These two categories are then factored together as identified in Table 4.13-2. For example, if a

TABLE 4.13-2
LEVELS OF VISUAL IMPACTS

¹   Adverse But Less than Significant Impacts are perceived as negative, but do not exceed environmental thresholds.
²   In some cases, Significant Impacts can be mitigated to a level that is not significant or can be avoided altogether with feasible mitigation. Without mitigation, the impact could exceed environmental thresholds. Impacts can be either Significant or Less Than Significant with Mitigation Incorporated, as applicable.

particular site is very scenic and the project blocks a significant portion of this view, then both the Impact Susceptibility and the Impact Severity are classified as High. The resulting impact is significant and not mitigable under the CEQA definition. If a project design is out of character with the existing neighborhood (Impact Severity is High) and the Impact Susceptibility has been designated as Moderate, then the visual impact is significant but has the potential for mitigation. All possible relationships between these two components are identified in Table 4.13-2 and are utilized in the determination of visual impacts.

The additional factor of local regulations must also be considered in the analysis. For example, if a project exceeds the allowed height limitations, this is considered a potentially significant impact because it has been so defined in the zoning ordinance.

The impacts below are evaluated on a site-by-site basis from each applicable KOP. Where appropriate, relevant mitigation measures are identified and numbered in sequence.

Construction-related impacts include the process of erecting the converter station and related cable and infrastructure connections, which is projected to take 27 to 30 months. While there would be moving equipment and erecting cranes which certainly would be visible from the adjacent KOPs, these visual impacts are classified as short term and, therefore, less than significant and no mitigation is required.

Operations-related impacts are defined as those impacts that would be visible while the converter station is in operation and visible over the lifetime of the structure. The potential for impacts is discussed on a KOP-by-KOP basis.

4.13.3.2  San Francisco HWC Converter Station

The proposed San Francisco HWC Converter Station is located on a 5.6-acre site set approximately 500 feet to the east of Illinois Street adjacent to 23^rd Street. Use of this site as proposed would require removal of two large existing warehouse structures adjacent to Warm Water Cove. The site is somewhat visible from Illinois Street (Photo A of Figure 4.13-5) and the Potrero Hill housing projects (Photo A of Figure 4.13-6), and would be directly visible from Warm Water Cove Park (Photo A of Figure 4.13-7). The most visible component would be the valve and DC hall structure, which has a ridgeline 64 feet in height and a building floor area of approximately 23,000 square feet. The electric switchyard includes a series of metal poles approximately 80 feet in height, which would be most visible from Warm Water Cove. In addition there are three alternative cable routings from the converter station to the PG&E Substation that would most affect views from Illinois Street and Potrero Hill (see Figure A.1-1). The westernmost of these alternatives would be either buried or above ground on 75-foot-tall, 115 kV poles. The easternmost alternative may either be buried or above ground. The middle or 45 degree angle alternative route would only be via subsurface cable. At this time, no supplemental planting or architectural design has been proposed as part of the San Francisco HWC Converter Station.

The converter station is located within an M-2 zone which allows an exemption to the 40-foot height limitation. There is also potential concern about shadows cast by Project components into Warm Water Cove. However, in this case with the demolition of a warehouse and its replacement with switch gear and poles that are more open, it appears that there would be a net reduction in shadows cast onto the water especially in the summer when the sun is farthest north of the equator.

KOP SF-1: 23^rd Street at Illinois Street. From this location, the visual changes would be the replacement of the large white masonry warehouse by the converter station valve and DC hall structure, and the possible addition of the overhead 75-foot-tall transmission towers. The 80-foot-high metal poles are visible in the background (Photo B, Figure 4.13-5). From this KOP, the Project structure would be neither out of scale with the adjacent buildings nor would it unfavorably contrast with the surrounding context; no scenic vista would be obscured. The above ground transmission towers (Photo B, Figure 4.13-5) would add somewhat to the visual clutter of the scene, but not to the level of significance. From a visual aspect, the environmentally superior choice would be to place these lines underground. The Impact Severity is classified as Low.

Since the Impact Susceptibility for the area is also Low, the resulting impact per Table
4.13-2 would be less-than-significant for this KOP.

KOP SF-2: Potrero Hill. There are glimpsed views of the Project site for residents of the housing projects on Potrero Hill. However, as can be seen (Photo B, Figure 4.13-6), the view is relatively distant and the converter station would replace structures of a similar size and character. Neither the new structures nor the alternative transmission lines would project to a height that would obscure views of the San Francisco Bay. They are neither out of scale nor unfavorably contrasting. The Impact Severity is classified as Low.

Since the Impact Susceptibility for the area is Low to Moderate, the resulting impact would be less than significant.

KOP SF-3: Warm Water Cove Park. The replacement of the two large warehouse structures by the Project structures, generally of the same scale, would result in greater visual clutter since the switchyard has a great deal of complexity (Photo B, Figure 4.13-7). Further, the overhead cable and the 80-foot-high poles would both add to the complexity and sense of view blockage even though the blockage is not of a scenic vista. The Impact Severity is classified as Moderate.

The Impact Susceptibility for the area is also Moderate (given that the views are from Warm Water Cove, a public place). The resulting impact would be considered adverse but less than significant.

Impact VIS-1: Converter Station Domination of View. Since the architectural design character of the building and the general character of proposed landscaping have not been identified in detail, there is the possibility of generating potentially significant visual impacts based upon the potential of the Project to dominate the scene or become obtrusive on views from Warm Water Cove Park.

While this impact has been classified as less than significant without design controls, it may still be adverse. This adversity can be lessened through the application of Mitigation Measures VIS-1a and VIS-1b.

Mitigation Measure VIS-1a: Plan Submittal Requirements for Building Materials and Colors. All major Project features, including buildings, structures, fencing, and sign backgrounds (excluding electric switch gear and related wires and cables, etc. which shall be galvanized gray as shown in the simulations) shall be painted with neutral tan or gray colors that will minimize the size and height of the facility, blend with adjacent structures and be compatible with natural landscapes where applicable. A specific painting plan shall be developed for approval by the agency with local jurisdiction to ensure that the proposed colors do not unduly contrast with the surrounding landscape colors. All treatments shall be in non-reflective colors. The painting plan shall be submitted sufficiently early to ensure that any pre-colored buildings, structures and linear facilities shall have colors approved and included in bid specifications for such buildings or structures.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Architectural design plans shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg, in consultation with the City and County of San Francisco, to monitor and ensure compliance

Mitigation Measure VIS-1b: Plan Submittal Requirements for Landscaping. A specific landscaping plan shall be prepared showing the location of proposed landscaping, the varieties and sizes of plants to be planted, and the proposed time of maturity for each species. Plants shall be selected from the approved species list prepared by the agencies with jurisdiction.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Landscaping plans shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg, in consultation with the City and County of San Francisco, to monitor and ensure compliance

Resulting Level of Significance. Application of Mitigation Measures VIS-1a and VIS-1b would reduce Impact VIS-1 to a less-than-significant level.

Impact VIS-2: Converter Station will Create Substantial Light and Glare. There is potential for the Project to cast more ambient light into the immediate area than the existing conditions. There is also the possibility that the luminaries of some of the lighting fixtures may be seen directly by either residents of Potrero Hill or users of Warm Water Cove Park, which through the abrupt contrast of the fixtures' light with the surrounding general darkness, may create the effect of glare.

While this impact has been classified as less than significant, without design controls it may still be adverse. This adversity can be lessened through the application of Mitigation Measure VIS-2.

Mitigation Measure VIS-2: Plan Submittal Requirements for Lighting. Except as required by security and worker-safety requirements, night lighting shall be hooded to direct illumination downward and inward toward the areas to be illuminated in order to minimize nighttime light and glare, backscatter to the nighttime sky, and visibility of lighting to public viewing areas. A specific lighting plan consistent with operational and safety needs and limiting the general lighting levels to a maximum reasonable level shall be submitted to each agency with jurisdiction for approval. The plan shall include provisions for timed and/or motion detection-controlled switches.

Implementation Responsibility:  Project proponent

Requirements and Timing:         A lighting plan shall be prepared by professionals qualified in the designated field of expertise; Lighting plans and revised design shall be submitted prior to final planning approval

Monitoring Requirements:          City of Pittsburg, in consultation with the City and County of San Francisco, to monitor and ensure compliance

Resulting Level of Significance. Application of Mitigation Measure VIS-2 would reduce Impact VIS-2 to a less-than-significant level.

Impact VIS-3: Creation of Visual Clutter. There is the possibility that views of the proposed HWC Converter Station from Warm Water Cove Park would be adversely affected without supplemental screening landscaping along the waterfront given the potential for the Project to be more obtrusive than the existing condition. This impact would be considered potentially significant.

Mitigation Measure VIS-3: Landscaping Plan. The view of the proposed HWC Converter Station from Warm Water Cove Park shall be improved by addition of landscaping screening. In order to improve views northward from Warm Water Cove Park, the applicant shall develop a landscape plan which provides screening foliage where consistent with facility location and safety. The landscaping plans shall be reviewed and approved by agencies with jurisdiction.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Landscaping plans shall be prepared by professionals qualified in the designated field of expertise; landscaping plans and revised design shall be submitted prior to final planning approval

Monitoring Requirements:          City of Pittsburg, in consultation with the City and County of San Francisco, to monitor and ensure compliance

Resulting Level of Significance. Application of Mitigation Measure VIS-3 would reduce Impact VIS-3 to a less-than-significant level.

4.13.3.3  Pittsburg Standard Oil Converter Station

The proposed Pittsburg Standard Oil Converter Station is located on a 7.5-acre site set back approximately 0.25 mile from the Pittsburg-Antioch Highway. Use of this site as proposed would require removal of several existing structures but not the existing vegetative screening on the adjacent site which is visible in Photo A of Figure 4.13-18 The most visible component of the Converter Station would be the valve and DC hall structure, which would have a ridgeline of 64 feet in height and a building floor area of approximately 23,000 square feet. To the north of the structure would be the proposed electric switchyard, which includes a series of metal poles 80 feet in height. A 230 kV AC, transmission line on 75-foot-talltowers would be constructed between approximately the railroad ROW and New York Slough. The balance of the AC line would be underground. At this time, no supplemental planting or architectural design has been proposed as part of the Project.

The governing zoning for this site is IG (General Industrial), which has a height restriction of 50 feet. Additional height is allowed equivalent to the number of additional feet the structure is set back from minimum requirements to a maximum of 75 feet. Towers and similar type structures can exceed this limit by up to an additional 20 feet.

Design Review approval by the Pittsburg Planning Commission is required for the site plan, architectural design of the structures, and site landscaping.

KOP P-1: Pittsburg-Antioch Highway. This view is taken from approximately 0.25 mile to the southeast of the site and shows the converter station behind the existing screening of vegetation along Dowest Slough/Kirker Creek in the midground (Photo B, Figure 4.13-18. In this context, the large DC/valve hall is co-dominant with the Delta Energy Center, which is shown on the right side of the photo. However, no scenic vista would be blocked nor would the development, including the proposed bridge over Kirker Creek associated with the new access road, be out of character (contrasting) with adjacent existing development. The transmission line and towers will not be visible from this location. The Impact Severity is classified as Moderate/Low.

Since the Impact Susceptibility for the area is Low, the resulting impact would be less than significant.

KOP P-2: Pittsburg-Antioch Highway. This view is taken approximately 0.5 mile to the east of KOP P-1 and demonstrates the overall industrial character of the area with Dow Chemical shown on the right side of the photo and a steel fabrication plant visible under the high water tank (Photo B, Figure 4.13-9). However, even from this distance the DC/valve hall dominates the scene and moderately contrasts even though no scenic vista is being blocked. While the transmission line and towers may be glimpsed from this KOP, they would be seen against the industrial background of the chemical plant and would be indistinguishable to the average viewer. The Impact Severity is classified as Moderate.

Since the Impact Susceptibility for the area is Low, the resulting impact with reasonable design and control of lighting and glare would be less than significant. Even so, there is potential for visual dominance of the Project by both design and by light and glare.

Impact VIS-1: Converter Station Domination of View. The Pittsburg Standard Oil Converter Station would be visible from the Pittsburg-Antioch Highway. Since the architectural design character of the building and the general character of proposed lighting have not been identified in detail, there is the possibility of generating significant visual impacts based upon the potential of the Project to dominate the scene or become obtrusive on views from the Pittsburg-Antioch Highway.

While this impact has been classified as less than significant, without design controls it could still be adverse. This adversity can be lessened through the application of mitigation measures VIS-1a, VIS-1b and VIS1c.

Mitigation Measure VIS-1a: Plan Submittal Requirements for Building Materials and Colors. Mitigation Measure VIS-1a described in Section 4.13.3.2 shall be applied at the Pittsburg Standard Oil Converter Station site. Architectural design and site plans, plus a color and material palette, shall be reviewed and approved by the Pittsburg Planning Commission. Final architectural plans and conditions of approval shall be reviewed and signed off by the appropriate planning and building officials prior to operation of the Project.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Architectural design plans shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Mitigation Measure VIS-1b: Plan Submittal Requirements for Landscaping. Mitigation Measure VIS-1b described in Section 4.13.3.2 shall be applied at the Pittsburg Standard Oil Converter Station site. Landscape design plans shall be reviewed and approved by the Pittsburg Planning Commission. Final landscape plans shall be reviewed and signed off by the appropriate planning and engineering officials prior to operation of the Project.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Landscaping plans shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Mitigation Measure VIS-1c: Landscaping Plan. The Applicant shall extend the landscape screening along the eastern property line, using plants compatible with the existing vegetation screen along the Pittsburg-Antioch Highway. Such screening would be most visible from KOP P-2 along the side of the facility. In addition, several clusters of major trees from the Pittsburg planting list shall be located to help visually break up the large vertical planes of the DC/valve hall. The intent is not to completely screen the structure, but to soften its mass by providing intervening tree forms. Landscape design plans shall be reviewed and approved by the Pittsburg Planning Commission. Final landscape plans shall be reviewed and signed off by the appropriate planning and engineering officials prior to operation of the Project.

Implementation Responsibility:  Project proponent

Requirements and Timing:         Landscaping plan shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Application of Mitigation Measures VIS-1a, VIS-1b and VIS-1c would reduce Impact VIS-1 to a less-than-significant level when applied to the Pittsburg Standard Oil Converter Station.

Impact VIS-2: Converter Station will Create Substantial Light and Glare. There is potential for the Project to cast more ambient light into the immediate area than the existing conditions. There is also the possibility that the luminaries of some of the lighting fixtures may be seen directly by travelers along the Pittsburg-Antioch Highway which through the abrupt contrast of the fixtures' light with the surrounding general darkness, may create the effect of glare.

While this impact has been classified as less than significant, without design controls it may still be adverse. This adversity can be lessened through the application of Mitigation Measure VIS-2.

Mitigation Measure VIS-2: Plan Submittal Requirements for Lighting. Mitigation Measure VIS-2 described in Section 4.13.3.2 shall be applied at the Pittsburg Standard Oil Converter Station site. Lighting plans shall be reviewed and approved by the Pittsburg Planning Commission. Final lighting plans shall be reviewed and signed off by the appropriate planning and building officials prior to operation of the Project

Implementation Responsibility:  Project proponent

Requirements and Timing:         A lighting plan shall be prepared by professionals qualified in the designated field of expertise; plans and revised design shall be submitted prior to final planning approval to ensure that the identified mitigation measure is satisfied

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Application of Mitigation Measure VIS-2 would reduce Impact VIS-2 to a less-than-significant level when applied to the Pittsburg Standard Oil Converter Station.

4.13.3.4  Offshore DC Cable Route

Given that the cable would be buried in the bed of San Francisco Bay, there are no visual impacts associated with the operation of the proposed AC/DC cables. Temporary construction impacts would be related to the cable laying process. The primary cable laying ship (Giulio Verne) is 133 meters (approximately 440 feet) in length and is considered of medium size; it would be only one vessel among a thousand in the Bay Area each month. The Giulio Verne (or comparable vessel) is expected to be used to lay cable west and south of the Carquinez Straits while a barge/tugboat would lay cable east of the Carquinez Straits to Pittsburg. The marine construction period is expected to last about 4 to 5 months and is considered short term in terms of visual impacts. Therefore, no significant visual impacts are expected to occur and no mitigation is necessary.