The East Span Project does not lie within the boundaries of any established residential neighborhoods. Land within the project is under institutional use. Project alternatives were analyzed for potential effects to local communities including effects on employment; community services; potential for displacement of residences, businesses, or public facilities; and consistency with existing land uses and development policies.

Project alternatives were analyzed for potential social and economic impacts. Socioeconomic impacts are considered to occur if a project:

• Induces substantial growth in a community
• Places demands on community facilities
• Disrupts existing patterns of interaction in a neighborhood
• Affects a low-income or minority community

The East Span Project is not expected to have adverse social or economic impacts on established neighborhoods or communities given the project’s location in an institutional and industrial setting and because project alternatives would replace an existing transportation facility with one of equal capacity. Any project-related changes to social or economic conditions in Bay Area neighborhoods or communities are expected to result from the employment effects of the large construction labor force that would be needed to construct the build alternatives.

Project build alternatives will generate demand for workers during the estimated three to five year construction period. Construction will generate direct construction jobs and spin-off service employment opportunities. Workers are expected to be recruited from the local labor force, with specialty skills being provided by workers from inside and outside the region.

The Bay Area has a large labor force and vibrant economy; thus, it is expected that the vast majority of the construction labor force would be workers already living in the area. However, some specific tasks, such as bridge iron workers, can only be done by a limited number of national contractors, resulting in a need to import specialist workers. In a worst-case scenario, in which there are many major construction projects occurring concurrently (compared to the base level), a shortfall of construction workers could develop in the region.

If a shortage developed, other workers would commute from outside the region (Central Valley) or take up temporary residence. Temporary construction workers often rent rooms or stay in motels during the work week, leaving their families behind. In addition to motels and rooms, there are more than 700,000 rental units within the Bay Area, so the potential impact of the project labor force would not be noticeable on the housing market. The Bay Area is a large and dynamic region. At any given time, some companies and agencies are reducing their labor force while others are increasing. There is a movement of workers and households in and out of the Bay Area at all times, and the demand generated by East Span build alternative construction activities would not cause an adverse impact on the general availability of labor supply, the housing market, or school enrollment.

Construction materials such as steel and concrete are not produced in the project vicinity and are likely to be purchased from other areas. Thus, the primary economic benefits of the project would be the direct construction jobs and the economic multiplier caused by local spending by the construction labor force. The Association of Bay Area Governments (ABAG) estimates that the number of local secondary jobs created is 1.44:1 construction job. Because the region has a large design and engineering labor force, this effect is likely to occur locally as well, providing additional labor jobs.

No-Build Alternative. The No-Build Alternative would not generate additional employment opportunities because no construction work beyond that completed under the prior Interim Retrofit Project would be undertaken.

Sources: Caltrans and Parsons Brinckerhoff, September 1998.

Assumptions: (1) 19 % of construction cost=labor@$95,000/person year (includes overhead)

(2) 100% of design & engineering=labor@$125,000/person year

(3) High range of cost estimate for this alternative as presented in Table 2.4-1

A forecast of construction workers required to construct a replacement bridge was estimated based on average annual employment of 600 people over the estimated five-year construction period, which includes dismantling the existing bridge. (The number of employees required will increase if the construction period is shortened.) Estimated direct labor by trade is: 102 iron workers, 100 pile drivers, 168 operating engineers, 100 carpenters, 65 concrete finishers, and 65 laborers and miscellaneous workers. With a peak period of two years for structural work on a new bridge, a peak demand of approximately 175 iron workers would be required.

Impacts of Build Alternatives. Build alternatives will generate direct and indirect labor demand during a period lasting up to five years. Workers are expected to be drawn from the regional labor pool with specialty trades generating demand from outside the Bay Area. A portion of the specialty trades may be attracted to the Bay Area for the duration of the project. Because of the large Bay Area economy, consisting of approximately three million jobs, worker-generated demands for housing or community services are not expected to have a noticeable effect on San Francisco, Oakland, or other Bay Area community housing stocks or services. The project is expected to generate a beneficial impact to San Francisco and Oakland economies by generating direct and indirect jobs.

A beneficial impact is anticipated and no mitigation is required.

Oakland. A potential construction staging area would be built at the Oakland Army Base. Construction activity would not affect neighborhoods in West Oakland. Because the project would be built within San Francisco Bay, there would be no impacts to community cohesiveness or other permanent impacts to the neighborhood.

San Francisco (Yerba Buena Island). Construction of a retrofit alternative, temporary detours and replacement structures all have the potential to cause temporary neighborhood impacts to a limited number of San Francisco residents on Yerba Buena Island (YBI). This would consist of occupants of U.S. Coast Guard (USCG) housing and potential residents of Quarters 1-10 which are presently unoccupied. Because the occupants are members of the military, the housing does not constitute a conventional neighborhood in terms of tenure or character. Consequently, construction-related impacts will be relatively minor, compared to an established residential neighborhood. There would be no permanent impacts.

No impacts to community services were identified under any of the categories: utilities, fire protection services, and police services. Permanent utility service would not be disrupted by the project; police and fire protection services would not change as a result of the project, and access to the Treasure Island (TI) elementary school would not be affected by the project.

Alternative S-4 would touch a portion of the EBMUD dechlorination facility on the Oakland Touchdown. If Alternative S-4 is carried through to final design, the alignment would be modified to avoid any adverse impacts to the facility. No mitigation would be necessary.

Executive Order 12898 and Federal Highway Administration (FHWA) guidance documents require consideration of the impacts on minority and low-income "populations" and "communities." This section determines whether the relevant neighborhoods are "minority" or "low-income" according to demographic data from the U.S. Census Bureau. This section includes a discussion of project impacts on these neighborhoods to determine whether or not these are "disproportionate" in comparison with impacts on other neighborhoods within the project corridor. The environmental justice analysis requires a balance test of impacts associated with each alternative on each neighborhood. The comparison is made between alternatives as a whole, since environmental justice community impacts are not expected to vary between specific alternatives.

According to U.S. Census Bureau data, YBI/TI does not meet the criteria as a minority or low-income neighborhood (see Section 3.1.4). Although there are no families living within the project area, the West Oakland census tract, which includes the Oakland Touchdown area, does meet the low-income criteria and the criteria of containing an identifiable minority population.

The paragraphs below consider whether the project alternatives would have disproportionate impacts on the low-income, minority neighborhood identified in West Oakland.

No-Build Alternative. The No-Build Alternative would not impose disproportionate adverse impacts on the identified minority population. Therefore, the No-Build Alternative would not cause disproportionate impacts on minority or low-income neighborhoods, and with respect to this alternative, the requirements of Executive Order 12898 regarding environmental justice have been satisfied.

Retrofit Existing Structure and Replacement Alternatives. Impacts to traffic, parking, land use, socioeconomic condition, community facilities, geology, soils, hydrology, water quality, hazardous materials, noise and vibration, and visual setting have been assessed for the build alternatives. Build alternatives would not impose disproportionate adverse impacts on the minority West Oakland neighborhood because no project-related construction would occur in or adjacent to the residential areas of West Oakland. As indicated in Section 4.1.1 above, the alternatives might result in increased employment opportunities from which West Oakland could benefit. The Retrofit Existing Structure and replacement alternatives would not cause disproportionate impacts on minority or low-income neighborhoods as defined by Executive Order 12898.

No disproportionate environmental impacts to low-income and minority neighborhoods would result from implementation of any of the project alternatives. No mitigation is required.

This section describes changes in land use that would occur as a result of the project alternatives.

Potential project-related changes to existing land uses on YBI and at the Oakland Touchdown are summarized in the following section. Permanent impacts are addressed here. Short-term construction-period impacts are addressed in Section 4.14.

No-Build Alternative. Implementation of the No-Build Alternative would not cause a change in any existing land uses on YBI. No impacts would result and no mitigation would be required.

Retrofit Existing Structure Alternative. The Retrofit Existing Structure Alternative would not cause any changes to existing land uses in the project area. The footprint of towers YB1, YB2, YB3, YB4, and Pier E1 would be expanded in size but would remain in their current locations. No new columns or piers would be constructed on the island. No impacts would result from the retrofit alternative and no mitigation would be required.

Replacement Alternatives. The replacement alternatives each begin east of the YBI Tunnel portal. The areas of impact for each of the three alternatives overlap. Many of the same buildings on the eastern edge of the island would be affected by all of the alignments.

Replacement Alternative N-2. Replacement Alternative N-2 is positioned to the north of the existing East Span. The alignment would place 14 piers between the YBI Tunnel east portal and the eastern edge of YBI. The alignment would also require construction of temporary detour structures to be used while the viaduct is retrofitted and transition structures on YBI are constructed. (Refer to Appendix A for alignment and detour structure drawings.) Impacts of the detour structures are discussed in Section 4.14.

The N-2 alignment would relocate the USCG access road to the south. This relocation would require the removal of Buildings 40 (administration), 75 (storage), and 270 (vacant).

An existing access drive serving vacant parcels at the northeast end of the island would be blocked (see Section 4.3.1). The alignment would not remove existing structures or block access to existing uses on the island.

The N-2 alignment would cross approximately 60 meters (190 feet) above vacant Buildings 213 and 262, but would not place columns at locations to obstruct access to the buildings. The alignment would be approximately 10 meters (33 feet) closer to Quarters 1 than the existing East Span (i.e., approximately 40 meters [130 feet] south of Quarters 1). The alignment would also be approximately 10 meters (33 feet) closer to Building 40. However, the proximity of the span would not affect access to either of these structures.

Potential for long-term impacts to existing land uses resulting from the N-2 Alternative would be limited to displacement of Buildings 40, 75, and 270 to relocate the USCG access road. Should Alternative N-2 be identified as the preferred alternative, Caltrans would work with the USCG to remove the facilities and provide reasonable compensation; relocate the structures; or redesign future access to avoid the structures, if possible. Based on these design considerations, no mitigation would be required.

Alternative N-6 would displace Buildings 40, 75, and 270 to construct a new access road and gate for the USCG station. Construction of Alternative N-6 would require that the existing drive and gate to the station be moved south.

The N-6 alignment would cross approximately 60 meters (190 feet) above vacant Building 262, but would not place columns at locations to obstruct access to the building. The alignment would pass over the southern half of vacant Building 213, and a support pier would be located at the base of a pedestrian stairway on the east side of the building; however, pedestrian access to the stairway would be maintained throughout the construction period, or alternate means of access to public transport would be provided. The alignment would be approximately 10 meters (33 feet) closer to Quarters 1 than the existing East Span, approximately 40 meters (130 feet) south of the building and approximately 10 meters (33 feet) closer to USCG Building 40, but would not affect access to the structure.

Potential for long-term impacts to existing land uses resulting from the N-6 Alternative would be limited to displacement of Buildings 40, 75, and 270 to relocate the USCG access road. Should Alternative N-6 be identified as the preferred alternative, Caltrans would work with the USCG to remove the facilities and provide reasonable compensation; relocate the structures; or redesign future access to avoid the structures, if possible. Based on these design considerations, no mitigation would be required.

Replacement Alternative S-4. Construction of Replacement Alternative S-4 across YBI would require 22 piers between the YBI Tunnel east portal and the eastern shoreline of the island. Temporary detour structures would be required on YBI during construction.

The S-4 alignment would cross approximately 60 meters (190 feet) above the northern half of Building 75, but would not place columns at locations to obstruct access to the building. The alignment would be approximately 30 meters (98 feet) closer to USCG Building 270 than the existing East Span. The S-4 Alternative alignment would place a pier at the location of Building 40 within the USCG complex, requiring removal of the structure. This two-story building is in use by the USCG for reserve training and USCG auxiliary functions. The S-4 Replacement Alternative would be located approximately 50 meters (164 feet) from Quarters 1 and 60 meters (197 feet) from Building 262.

Final design studies would be conducted for Replacement Alternative S-4, if identified as the preferred, to change the proposed locations of footings and support piers to avoid Building 40. If Building 40 cannot be avoided during final design, Caltrans will coordinate with the USCG concerning relocation of uses in the affected buildings (see Section 4.1.5).

Land Use Impacts at the Oakland Touchdown Area. The N-2 and N-6 replacement alternatives touch down to the north of the existing East Span while S-4, the southern alignment alternative, touches down south of the existing structure.

No-Build Alternative. Implementation of the No-Build Alternative would not cause a change in any existing land uses in the Oakland Touchdown area. No impacts would result and no mitigation would be required.

Retrofit Existing Structure Alternative. The Retrofit Existing Structure Alternative would not cause any changes to existing land uses in the Oakland Touchdown area. The bridge footprint would be modified only to increase the size of Pier E-23 at the western end of the touchdown area. No impacts would result from the retrofit alternative and no mitigation would be required.

Replacement Alternatives N-2 and N-6. Replacement Alternatives N-2 and N-6, located to the north of the existing span, would have a similar approach to the Oakland Touchdown area. Both of the northern alignment alternatives will place five columns in the Oakland Touchdown area. The northern alignments would require the permanent displacement of 0.2 hectare (0.5 acre) of the City of Oakland-designated "Resource Conservation" lands to the north of the existing alignment.

Joint planning has been under way since 1997 with the City of Oakland, the Port of Oakland, East Bay Regional Park District (EBRPD), ABAG/Bay Trail, U.S. Army Base Reuse and Closure (BRAC), National Park Service, and the San Francisco Bay Conservation and Development Commission (BCDC) to coordinate enhancement of the Oakland Touchdown area. Mitigation for impacts to "Resource Conservation" lands is being addressed through this joint planning process described in Section 4.9 and includes the possible creation of a public park and access area at the western end of the touchdown. Caltrans is already required to provide public access improvements in this area as part of the BCDC permit for the I-880/Cypress Replacement Project and the I-80 HOV Flyover Project. However, while these projects could result in 700 square meters (7,500 square feet) of public access improvements, the joint planning effort under way for the East Span Project would potentially provide up to 6.48 hectares (16 acres) for public access.

Replacement Alternative S-4. Replacement Alternative S-4 would place five columns in the Oakland Touchdown area. The alignment would occupy a portion of the first 450 meters (1,500 feet) of the Oakland Army Base vacant land to the south of the existing East Span and open storage areas used by Caltrans. Portions of the Caltrans-owned open storage areas on the south side of the span would be displaced by the S-4 Alternative.

Reduction of land within the Oakland Army Base would not result in a land use impact. If the land is used for park space, as is currently being discussed, joint park planning would wait to configure parkland design to accommodate the S-4 alignment.

The No-Build Alternative would not displace any existing residential, commercial or public buildings. Of the build alternatives, the N-2 and N-6 Replacement Alternatives would require the displacement of Buildings 40, 75, and 270 on YBI (see Section 4.1.4, "Land Use Impacts on YBI" above). Replacement Alternative S-4 would require the displacement of Building 40.

If final design studies cannot avoid the displacement of Buildings 40, 75, and 270, relocation benefits and assistance will be provided to the USCG to either move the structures or find replacement facilities. Caltrans will coordinate with the USCG to provide comparable facilities with as little inconvenience as possible.

The purpose of this section is to evaluate the relationship between the proposed project and anticipated development trends at YBI and the Oakland Touchdown area.

The Treasure Island Draft Reuse Plan includes "Minimum" development scenarios based upon the existing capacity and access and a guiding policy for development of Naval Station Treasure Island which states that development should be limited to uses for which access can be accommodated primarily by ferry.

Vehicular access is a major constraint to development on YBI/TI. The East Span Project will not increase the SFOBB’s capacity nor will it improve the access points from the SFOBB to YBI/TI. The City and County of San Francisco’s (CCSF’s) Treasure Island Draft Reuse Plan (TIDRP) includes development scenarios based on existing capacities and access and states that a guiding policy for development is to limit uses to those for which access can be accommodated primarily by ferry.

The development potential of Yerba Buena Island would be affected by the physical location of the project. Due to the steep topography of most of the island, the eastern end is considered by the CCSF to be the only viable location for development.

No-Build Alternative. The No-Build Alternative would not conflict with Draft TI Reuse Plan development scenarios, although vehicular access to and from the East Bay could be affected in the aftermath of an MCE.

Retrofit Existing Structure Alternative. Expansion of existing East Span columns on YBI would not conflict with redevelopment scenarios for YBI. The Retrofit Existing Structure Alternative is consistent with the reuse plan in that it does not include modifications to YBI on- and off-ramps that would change the capacity of existing vehicular access. YBI ramps are not owned by Caltrans and are not critical to providing a lifeline connection in the project corridor. Therefore, the retrofit alternative would not conflict with the transportation access assumptions of the draft plan.

No long-term impacts would result from implementation of the Retrofit Existing Structure Alternative and no mitigation measures would be required.

The northern alternatives are consistent with the transportation element of the reuse plan because they would not modify YBI on- and off-ramps to change the capacity of existing vehicular access. The ramps are not owned by Caltrans and are not critical to providing a lifeline connection in the project corridor. One eastbound on-ramp is proposed for modification under the replacement alternatives, but would not change access capacity to the island. Therefore, Replacement Alternatives N-2 and N-6 would not conflict with the transportation access assumptions of the draft plan.

Caltrans has initiated consultation with the CCSF concerning the effects of the northern alignment alternatives and reuse plans. Joint planning efforts are also being discussed. The EIR/EIS for reuse plan has not yet been issued.

Caltrans will continue to coordinate with the CCSF. Should a northern alignment alternative be identified as the preferred, Caltrans will work with San Francisco representatives during final design to minimize the amount of land required for on-island bridge footings and columns.

Replacement Alternative S-4. The S-4 Replacement Alternative would locate the replacement structure to the south of the existing East Span and remove the existing bridge. As a result, the project would open up increased area for YBI redevelopment. Approximately 0.8 hectare (2.0 acres) of land that is currently occupied by the existing span could become available for development. This would be a beneficial impact as it relates to CCSF’s redevelopment of YBI.

The development potential of the USCG property would be affected by project build alternatives. As part of the Base Reuse and Closure (BRAC) process, the Navy transferred 4.3 hectares (10.6 acres) to the USCG in April 1998. Of this land, 1.1 hectares (2.7 acres) is within the project area, and approximately 0.41 hectares (1 acre) is highly developable. No specific master plan has been developed for expansion of the existing USCG facility.

No-Build Alternative. The No-Build Alternative would not affect existing USCG facilities. The No-Build Alternate would not limit future redevelopment to a degree beyond the limitations currently imposed by the existing East Span.

Retrofit Existing Structure Alternative. Expansion of existing columns and footings would not conflict with existing USCG facilities or limit future redevelopment to a degree beyond the limitations currently imposed by the existing East Span.

Replacement Alternatives N-2 and N-6. The northern replacement alternatives would remove the existing structure, opening up land on the southeastern portion of YBI for USCG use. Although no future development plan is in place, this increased area, if made available to the USCG through the BRAC process for Naval Station Treasure Island and determined to be feasible for development, could increase future expansion options. This is considered a potentially beneficial impact to the USCG.

Replacement Alternative S-4. Footings and support piers for Replacement Alternative S-4 would use the southeastern portion of YBI and eliminate the potential for expansion at this location. Because plans show no development for this area, no impact would result and mitigation would not be required.

The Port of Oakland has long-term plans under development that would expand Port operations onto existing Oakland Army Base property at the Oakland Touchdown.

No-Build Alternative. The No-Build Alternative would not conflict with Port of Oakland redevelopment plans.

Retrofit Existing Structure. The Retrofit Existing Structure Alternative would not require the use of existing Oakland Army Base property and would not conflict with Port of Oakland redevelopment concepts.

Replacement Alternatives N-2 and N-6. The northern alignment alternatives would not use Oakland Army Base property and would not conflict with Port of Oakland redevelopment concepts.

Replacement Alternative S-4. Replacement Alternative S-4 would adversely affect the ability of the Port of Oakland to develop and expand its existing facilities, as permitted under the BCDC-approved Seaport Plan. The Port estimates that the alignment would result in the loss of 6 to 12 percent of the area that could potentially be conveyed to the Port through the Oakland Army Base BRAC process. The southern half of the Oakland Touchdown area represents one of the few opportunities for the Port to expand their operations in the Oakland Touchdown area in the foreseeable future (see letter to Mr. Jon Rubin from Port of Oakland dated August 19, 1998, in Appendix G). These factors suggest that the S-4 Alternative may have a substantial effect on industrial/transportation-oriented development trends on the southern half of the Oakland Touchdown area.

Caltrans has initiated consultation with the Port of Oakland concerning development plans for the southern half of the Oakland Touchdown area. Caltrans and the Port of Oakland are participants in a joint planning effort to establish a public park and access area at the Oakland Touchdown area. (See discussion of Public Parks and Open Space below.) Representatives of the Port have stated their intention to work with the Oakland Gateway Joint Planning Group to develop design concepts which accommodate the East Span Project, Port activities, and public open space in the Oakland Touchdown area.

Caltrans will continue to coordinate with the Port of Oakland and other participating agencies in developing park and open space concepts for the Oakland Touchdown area.

Joint planning has been initiated with the City of Oakland, Caltrans, the Port of Oakland, EBRPD, ABAG/Bay Trail, U.S. Army, National Park Service, and BCDC to create a "gateway" public open space at the Oakland Touchdown. East Span Project build alternatives have been identified as key components of the area.

No-Build Alternative. Under the No-Build Alternative, Caltrans would not continue to participate in cooperative park planning for the Oakland Touchdown area. However, BCDC’s requirement (from the Cypress Project) that Caltrans implement public access improvements on the Touchdown would not be affected. Similarly, the EBRPD plans for a public park along the southern edge of the touchdown would not be affected by this alternative. The No-Build Alternative would not prohibit EBRPD development of parkland at the Oakland Touchdown area; therefore, no impact would occur and no mitigation would be required.

Retrofit Existing Structure. The Retrofit Existing Structure Alternative would provide limited opportunities for cooperative park planning because it would not contribute to assembly of a large contiguous parcel for open space use. However, BCDC’s requirement (from the Cypress Project) that Caltrans implement public access improvements in the Touchdown area would not be affected. Similarly, the EBRPD plans for a public park along the southern edge of the touchdown would not be affected by this alternative. The Retrofit Existing Structure Alternative would not prohibit EBRPD development of parkland at the Oakland Touchdown area; therefore, no impact to development of parkland would occur and no mitigation would be required.

Replacement Alternatives N-2 and N-6. Cooperative planning to date has resulted in the development of design concepts for a gateway park under either the N-2 or N-6 Alternatives. The northern alignment alternatives would contribute to assembly of a large developable space to the south of the East Span alignment. Therefore, the northern alignment alternatives would have a beneficial impact on cooperative park development at the Oakland Touchdown.

Replacement Alternative S-4. The S-4 Replacement Alternative would contribute to the assembly of a large contiguous north-facing parcel for park development at the Oakland Touchdown. Therefore, the S-4 Replacement Alternative would have a beneficial impact on cooperative park development at the Touchdown.

Under BCDC Permit 11-93, issued to Caltrans for the I-880/Cypress Freeway Replacement and I-80 HOV Flyover projects, Caltrans prepared conceptual design sketches for Bay access sites within the Oakland Touchdown area. The permit includes a fee-in-lieu provision should construction of the sites prove infeasible. Replacement alternatives would each require ongoing consultation with BCDC to determine the optimum locations of these public access overlooks.

No-Build Alternative. The No-Build Alternative would not interfere with implementation of the Bay access overlooks. No impact would occur and no mitigation would be required.

Retrofit Existing Structure Alternative. The Retrofit Existing Structure Alternative would not conflict with provision of the Bay access sites. However,

construction of the retrofit alternative could limit access to the planned sites during bridge retrofit construction activities.

Replacement Alternatives N-2, N-6, and S-4. Each of the proposed replacement alternatives would have an effect on the Special Conditions found in Permit 11-93. The northern alignment alternatives will preclude the implementation of an access area required by the BCDC for the northern side of the Oakland Touchdown. The S-4 Replacement Alternative would preclude the development of a west-facing lookout area, bicycle path, lookout roadway, and parking area permitted by the BCDC.

Caltrans has submitted to BCDC a request to amend Permit 11-93 to delay implementation of the access areas until completion of East Span construction. On July 31, 1998, BCDC amended Permit 11-93 to extend the period for construction of the public parks and overlook areas to December 31, 2006.

Caltrans will consult with BCDC following identification of a preferred East Span Project alternative to determine necessary Bay access modification or requirements under Permit 11-93. Any modifications to Bay access requirements will be identified as conditions in a future amendment to Permit 11-93.

The purpose of this section is to evaluate the relationship between the proposed project and existing land use, transportation, and BCDC policies guiding future development in the western and eastern touchdown areas.

Treasure Island Draft Reuse Plan (The City and County of San Francisco). The proposed project is consistent with CCSF’s policies for future development and land uses within the project area. The replacement of the East Span will have no effect on CCSF’s program to implement the guiding policies of the TIDRP (as listed on p.29) nor on CCSF’s program to implement the goals and policies of CCSF’s Master Plan. The TIDRP and CCSF’s Master plan both are written with the clear assumption that the East Span will continue to provide an essential link for auto traffic between YBI and the East Bay.

The East Span Project would adversely impact CCSF’s current development scenario for the eastern end of YBI. The Treasure Island Draft Reuse Plan (TIDRP) goals and policies identify the eastern end of YBI for publicly oriented uses and lodging. However, the goals and policies also identify the Bay Bridge structure and ramps as one of the institutional uses to be provided on YBI, as the bridge provides an essential link for auto traffic between YBI and the East Bay. Planned uses on the western side of YBI, and on Treasure Island itself, would not be affected by the East Span Project. The DEIR/DEIS for the reuse plan has not been issued yet.

The SFOBB is an integral part of the existing system that supports Oakland’s vision of the City’s "primacy as a transportation hub connecting the Bay Area with the Pacific Rim and the rest of the United States" (City of Oakland, Vision 2015).

The Oakland Touchdown area is located immediately adjacent to the City’s seaport area (i.e., Port of Oakland facilities). The seaport area is classified as a showcase district in the City’s General Plan. Showcase districts are dynamic areas that can respond to broad trends and market demands. The policy framework of the plan supports these districts in their continued growth and regional importance. The SFOBB provides an important link between the City’s showcase districts, San Francisco, and the San Francisco Peninsula.

Oakland Policies t 4.5, t 4.9, and t 6.3 support preparation of a Bicycle and Pedestrian Master Plan, the creation of a "gateway" public access area at the terminus of the East Span, and making the waterfront accessible to pedestrians and bicyclists. The East Span Project includes participation by Caltrans in joint planning efforts to create public access areas in the Oakland Touchdown area that will support implementation of these City policies. These characteristics of the SFOBB project also support the Waterfront Goals of the General Plan, relative to promoting public access to the waterfront.

The "New Bay Bridge," as the SFOBB East Span Project is described in Regional Access: Policies in Action, Chapter 3 of the City’s General Plan, provides opportunities for increased bicycle, pedestrian, and transit access to the bridge. Additionally, the General Plan recommends that new parks and open space at the Oakland Touchdown should be integral components of the project. The proposed project includes features which are in keeping with the City’s policies.

Port of Oakland. The Port of Oakland has formally requested through the BRAC process that the Oakland Army Base property be conveyed to the Port to accommodate a planned expansion of Port facilities. The SFOBB East Span Project is consistent with the Port of Oakland’s plans to expand its capacity and create additional areas for staging and storage. The BCDC-approved Seaport Plan allows the Port to increase the amount of usable land on the Touchdown by filling in a portion of the Bay south of the existing Touchdown area. This activity would not be precluded by any of the proposed alignment alternatives; however, the S-4 Replacement Alternative may affect the Port of Oakland’s ability to use the area for Port purposes.

U.S. Coast Guard (USCG). The USCG does not currently have a master plan in place for the YBI facility. In general, the USCG plans to maintain its current level of operations at the YBI facility, including 24-hour search and rescue, repair and maintenance of buoys, vessel traffic service, and law enforcement. The project as proposed would not substantially affect the current level of operations.

East Bay Regional Parks District (EBRPD). The EBRPD has formally requested through the BRAC process that a portion of the Oakland Army Base property south of the existing span be conveyed to EBRPD for development as a public park and access area. The East Span Project is generally consistent with the EBRPD’s intention to provide a public park on the Touchdown. Preliminary coordination among the U.S. Army, EBRPD, and the Port of Oakland for joint planning of the area indicates that the proposed development is also consistent with the City of Oakland and BCDC policies and planning designations. Preliminary visions for the park include extension of the Bay Trail to the western edge of the Touchdown area, public amenities, and open space. The configuration of the trail and the open space is contingent upon selection of the East Span Project preferred alternative.

City of Oakland – Vision 2000. Oakland’s transportation policy includes the following:

Objective T4. Increase use of alternative modes of transportation.

Policy T4.8 - Accommodating Multiple Types of Travel on the Bay Bridge. The City should encourage the design and engineering for the new Bay Bridge to accommodate multiple means of access and travel by automobiles, trucks, transit, bicycles, pedestrians, and future mass transit.

Each of the East Span Project replacement alternatives would accommodate multi-modal travel on the bridge. HOV bypass ramps would remain in operation at both the west and east bridge approaches to encourage carpools, vanpools, and bus transit use. Provision for future mass transit would be accommodated by continuation of AC Transit bus service and by design of the replacement structures to accommodate loading for light rail transit vehicles. Replacement alternative designs also include a pedestrian/bicycle path. The proposed project is consistent with this policy.

The East Span Project includes coordination with the agencies concerned with future uses of land in the Eastern Touchdown area. Joint planning activities involving the City of Oakland, Port of Oakland, EBRPD, BCDC, National Park Service, U.S. Army, and Caltrans are in progress.

City and County of San Francisco Master Plan. CCSF’s transportation policy includes the following:

Policy 1. Involve citizens in planning and developing transportation facilities and services, and in further defining objectives and policies as they relate to district plans and specific projects.

The East Span Project is consistent with this policy as it has provided many opportunities for public involvement in the process.

Policy 2. Where significant transit service is provided by buses, bridges and freeways should have exclusive bus lanes.

Policy 3. The existing vehicular capacity of the bridges, highways and freeways should not be increased and should be reduced where possible.

The East Span Project is consistent with this policy as it does not propose an increase to existing capacity.

Policy 4. Accommodate bicycles on regional transit facilities and important regional transportation links.

The East Span Project replacement alternatives include designs for a pedestrian/bicycle path. The project is potentially consistent with this policy.

Association of Bay Area Governments – The Bay Trail. ABAG’s plans for trails include the following:

Transportation Access Policies.

The East Span Project would be consistent with these policies because the replacement alternatives would provide an important connection to Bay Trails on both sides of the Bay. The East Span Project would improve access to the bridge and would enhance the safety of the bridge itself. The pedestrian/bicycle path is to be funded as outlined in Section 188 of the California Streets and Highways Code (CSHC).

Land Use. BCDC requires that every project provide the maximum feasible public access to the surrounding waterfront and/or shoreline. In joint planning meetings for the conceptual gateway park at the Oakland Touchdown area, BCDC concurred that it would consider combining the requirements to maximize public access specified in Permit 11-93 with any additional Bay access permit conditions that might be required for the East Span Project.

The East Span project would be consistent with this public access policy as Caltrans would provide bicycle, pedestrian, and vehicular access to the Touchdown area as part of both the East Span Project and BCDC’s previous conditions of approval for the Cypress and I-80 projects. Shoreline public access is required as part of the Cypress and I-80 projects. Access could potentially be increased through a joint Port/EBRPD effort to create a public park of up to 6.48 hectares (16 acres) on the western end of the Touchdown (see the East Bay Regional Parks District discussion below for further details).

The proposed project is consistent with the BCDC’s policies for future development as contained in the San Francisco Bay Plan, and the replacement of the SFOBB East Span will have no effect on the BCDC’s program to promote its policies guiding land use and development around the Bay. The Bay Plan strongly encourages that new transportation facilities be designed to encourage usage of mass transit. The proposed project is consistent with this policy, as the proposed alternatives would maintain the HOV bypass lanes at the toll plaza and west approach that presently take buses and carpools around congestion points. The Bay Plan also strongly encourages development and use of public parks. The configuration of overlooks required as part of the Cypress and I-80 projects would be affected by the East Span Project. However, given the intent of EBRPD and other parties to provide a much larger area for public access and amenities south of the span, Bay access requirements for parks and overlooks are expected be fulfilled. EBRPD plans for this area are independent of the East Span Project.

Transportation. The BCDC Bay Plan includes the following:

Policy 4. If a route must be located across a waterway, the following provisions should apply:

The East Span Project is consistent with BCDC policy "a." All alternatives propose a bridge crossing. Concerning policy "b", the height of all alternatives under consideration has been set in consultation with the USCG to provide adequate navigational clearance. Project alternatives would not require new fill for ancillary facilities. The project alternatives are, therefore, consistent with policy "c". Although the project does not propose a new route over the Bay, project alternatives are consistent with policy "d" in that consideration is being given to accommodation of structural loading requirements for future light rail transit.

Dredging and Fill. Bay Plan Dredging Policy 1, sets policies to prevent sedimentation resulting from dredging projects by stating that dredge materials be disposed of by:

1. Dry land disposal
2. Placement as fill in approved locations
3. Ocean disposal
4. In-Bay disposal at designated locations

Dredging required for the project would result from construction activities (see Section 4.14.9). Caltrans has initiated consultation with BCDC and other regulatory agencies through the Dredged Materials Management Office (DMMO) concerning disposal of dredged materials (see correspondence in Appendix G).

The Bay Plan regulates fill, requiring that fill be minimized and permitted only if it meets certain conditions. The condition that applies to the East Span Project is Condition #2, fill required for which there is no other alternative (i.e., airports, roads, and utility routes). The East Span Project is consistent with this policy because alternatives would be bridge structures. Fill associated with the build alternatives would be limited to bridge piers and limited fill at the bridge approach structures.

Visual. Bay Plan policies related to appearance of bridge structures address maximization of views to and from bridges and the visual prominence of bridge towers. The Retrofit Existing Structure Alternative is generally consistent with these policies in that retrofit of the existing bridge would not change existing railing heights or add substantial new superstructure that would decrease motorists’ views. Modifications to substructure, including addition of two bridge piers and expansion of existing piers would not change the basic visual form of the existing structure.

The replacement alternatives are consistent with Bay Plan visual policies. Bay Plan policies concerning views to and from the bridge and tower type and design were incorporated into design recommendations developed by the MTC Bay Bridge Design Task Force Engineering and Design Advisory Panel (see Appendix E).

Bay Plan Conformity Determination. Caltrans has initiated and will continue coordination with BCDC throughout the environmental phase of the project to assure project conformity with the Bay Plan (see Appendix E for discussion of BCDC participation in the NEPA/404 Integration MOU process) and to assure that the identified preferred alternative in the Final EIS would conform to Bay Plan policies. BCDC requires an approved Final EIS and detailed engineering design to make their Federal Bay Plan consistency determination.

The Final EIS and detailed engineering will be provided to BCDC during final project design, after the Final EIS and Record of Decision approval, for BCDC use in its federal consistency and Bay Plan permit process.

The proposed alternatives would affect transportation, including local traffic, transit, and maritime traffic. The alternatives would also affect building and parcel access and parking on YBI and in the Oakland Touchdown area. Construction-related impacts are discussed in Section 4.14

For each alternative, changes in vehicular traffic circulation, operations, and access time are identified, and measures are proposed to mitigate potential impacts.

Traffic operations under the No-Build Alternative and the Retrofit Existing Structure Alternative would remain the same as under existing conditions. Each of the East Span replacement alternatives may improve traffic operations on the SFOBB: the addition of 3-meter (10-foot) shoulders on both sides of the roadway would provide refuge for disabled vehicles. This may reduce non-recurrent congestion caused by minor accidents or stalls that block one or more lanes of traffic. The extent of non-recurrent congestion caused by major incidents is unlikely to be affected by the addition of a shoulder.

All of the proposed alternatives for the East Span replacement may result in long-term adverse impacts to SFOBB traffic operations during traffic incidents. When an incident occurs on a typical freeway segment, secondary congestion frequently occurs in the opposite direction of travel as a result of drivers slowing to view the incident. When an incident occurs on either the upper or lower deck of the existing SFOBB, there is currently no impact to traffic headed in the opposite direction because drivers are unable to see opposing traffic or incidents. The proposed replacement structures would place eastbound and westbound traffic at the same level, creating opportunities for drivers to see incidents on the opposite structure, which may cause delays in the non-incident travel direction. A glare screen installed on the median barrier railing could minimize the visibility of incidents to opposing traffic.

There would be no long-term impacts to access or transit operations on YBI, from the No-Build Alternative, Retrofit Existing Structure Alternative, or the replacement alternatives. The replacement alternatives would, however, create long-term changes in traffic circulation. Neither the No-Build nor the Retrofit Existing Structure Alternative would affect traffic circulation on YBI.

Traffic Circulation. For each of the East Span replacement alternatives, the East Span Project would restore the original roadways and driveways on YBI following construction. The alternatives would have no impact on long-term vehicular access and circulation, with the following exceptions.

Replacement Alternative N-2 Two columns would encroach about 4 meters (13 feet) into the southern edge of the paved area of the hairpin turn on Macalla Road at the undercrossing. Narrowing the road to accommodate these columns would potentially conflict with turning movements of large vehicles.

Three bridge columns would be located in the right-of-way of the existing USCG station entrance road, potentially blocking vehicle passage.

To accommodate turning of large vehicles, Macalla Road would need to be widened to the north, making it marginally steeper.

Construction of Alternative N-2 would require relocation of the existing USCG station access road and gate. Relocation of the road to the south is proposed as shown on Figures 2-7.1a and 2-7.1b in Appendix A.

Replacement Alternative N-6. Columns would encroach 6 and 3 meters (20 and 10 feet), respectively, into the southern edge of the paved area of the hairpin turn on Macalla Road at the undercrossing. Narrowing the road to accommodate these columns would potentially conflict with turning movements of large vehicles.

A column would encroach about 5 meters (16 feet) into the west side of the intersection of the USCG station entrance road and the first east/west driveway. The intersection would need to be realigned to the east and the driveway re-graded, which may require a new retaining wall.

To accommodate turning of large vehicles, Macalla Road would need to be widened to the north, making it marginally steeper.

Construction of Alternative N-6 would require relocation of the existing USCG station access road and gate. Relocation of the road to the south is proposed as shown on Figures 2-10.1a-c in Appendix A.

Replacement Alternative S-4 Two columns would encroach about 2 meters (6.5 feet) into the southern edge of the paved area of the hairpin turn on Macalla Road at the undercrossing. Narrowing the road to accommodate these columns would potentially conflict with turning movements of large vehicles.

To accommodate turning of large vehicles, Macalla Road would need to be widened to the north, making it marginally steeper.

No-Build Alternative, Retrofit Existing Structure Alternative, Replacement Alternatives N-2 and N-6. The No-Build Alternative, Retrofit Existing Structure Alternative, and Replacement Alternatives N-2 and N-6 would have no long-term impacts to traffic circulation, access, or transit.

Replacement Alternative S-4. Replacement Alternative S-4 would not affect existing transit service in the Oakland Touchdown area, but would require modification of existing access patterns.

Under Replacement Alternative S-4, Burma Road and the existing Caltrans maintenance road would need to be realigned. Port operations to the east of the S-4 alignment would continue to be accessed by Burma Road, which would be truncated at existing Terminal Seven. Access to the western end of the Touchdown area would be reconfigured to the north, using an extension of the Radio Point Beach access road. No loss of access would occur to Caltrans maintenance buildings or other utility structures at the western end of the touchdown. (See Figures 2-11.4 and 2-11.5 in Appendix A.)

Local access roadway reconfigurations would be part of the construction of the S-4 Replacement Alternative. Realigned access roadways would serve existing facilities and any future park development. No impacts due to change in access would result; therefore, no mitigation is proposed.

Pedestrian and non-motorized traffic is currently prohibited on the existing East Span and no dedicated, signed pedestrian/bicycle paths exist within the project area. Project alternatives have been assessed for potential to accommodate planned and proposed pathway connections and the replacement alternatives each incorporate a pedestrian/bicycle path.

Citizen participation in planning for the pedestrian and bicycle path on the East Span has been facilitated by the MTC and Caltrans through the Bay Bridge Bicycle/Pedestrian Advisory Committee (BPAC) and the MTC Elderly/Disabled Advisory Committee (EDAC).

There are no signed bicycle paths or lanes on YBI and the U.S. Navy and CCSF have no plan in place for the creation of a pedestrian/bicycle facility network on the island. Pedestrian and bicycle use of public street rights-of-way on YBI would be possible under any East Span Project alternatives. Therefore, project alternatives are not expected to have an impact on existing pedestrian and bicycle circulation on YBI.

However, the staircase on YBI linking the USCG base with the bus stop at the top of the hill would be displaced due to the placement of the bridge footings for Replacement Alternatives N-2 and N-6.

The stairway would be rebuilt at a new location or in a new alignment to avoid the new bridge footings. Caltrans would select the site for the replacement stairway in consultation with the USCG, U.S. Navy, and CCSF.

No-Build and Retrofit Existing Structure Alternatives. The No-Build and Retrofit Existing Structure Alternatives would have no impacts to pedestrian and bicycle circulation in the Oakland Touchdown area.

Replacement Alternatives. The replacement alternatives would create no permanent impacts to pedestrian and bicycle circulation in the Oakland Touchdown area. Each of the replacement alternatives would provide pedestrian/bicycle path access to any Bay or future park sites and would provide sufficient vertical clearance where necessary to permit a bicycle and rider to travel under bridge structures.

Proposed bridge alternatives have been evaluated for potential to provide pedestrian and bicycle access to and on the East Span. Criteria used to assess project impacts are:

• Ability to incorporate a pedestrian and bicycle path on the East Span

• Suitability of profile grades

• Connectivity to pedestrian and bicycle access at either the Oakland Touchdown area or YBI

• Creation of dangerous or inconvenient features that affect access at the Oakland Touchdown area or YBI

Path Accommodation and Placement. The No-Build and the Retrofit Existing Structure Alternatives do not incorporate a new pedestrian and bicycle path. The existing cross section of the bridge has five 3.3-meter (11-foot) travel lanes with no roadway shoulders, limiting the ability to restripe the bridge deck to accommodate a path on the bridge. A pedestrian and bicycle path could, however, be added to the exterior of the cantilever structure as a separate project. The No-Build and Retrofit Existing Structure Alternatives would not preclude a pedestrian and bicycle path.

Path Accommodation. A pedestrian and bicycle path has been incorporated into each replacement alternative (see Figure 2-8 in Appendix A). A path on the replacement alternatives would be constructed on the south side of the eastbound structure. The path would be 4.7 meters (15.5 feet) wide and 0.3 meter (1 foot) higher than the adjacent travel lanes. This configuration was requested by the advisory committee and the MTC. Provision of pedestrian/bicycle access on the East Span would be a beneficial effect.

Access at Yerba Buena Island. A path located on the south side of the eastbound replacement structure would connect with Treasure Island Road on YBI. Pedestrians and bicyclists using the SFOBB East Span pedestrian/bicycle path would be provided with direct access to existing street rights-of-way (Treasure Island Road) on YBI. The connection would allow for circulation on YBI and TI streets, except those streets with restricted access. Caltrans will incorporate directional signage for path users into the project design. Should the Navy or the CCSF desire that access be specifically directed, limited, or prohibited, Caltrans will work with these agencies to design signage or barriers.

Access at Oakland Touchdown Area. Access to and from the replacement alternatives would be from the south side of the eastbound structure. It is likely that a future Bay Trail extension would connect with the East Span structure.

Each of the East Span Replacement Alternatives would provide a pedestrian and bicycle path between YBI and the Oakland Touchdown area. Provision of the path would be in conformance with the following local plans:

• City of San Francisco, Naval Station Treasure Island Reuse Plan,
• San Francisco Bay Conservation and Development Commission,
• City of Oakland Pedestrian and Bicycle Master Plan,
• Association of Bay Area Governments Bay Trail Plan.

All East Span Project alternatives could accommodate the existing Caltrans bicycle shuttle service.

For each alternative, changes in long-term parking supply resulting from project alternatives have been identified.

Retrofit Existing Structure. Strengthening of existing column YB3 under the Retrofit Existing Structure Alternative would eliminate approximately four informal parking spaces in the paved area east of Quarters 1. Given the large undeveloped area available for parking, the loss of four parking spaces at the eastern end of this area would not contribute to unmet parking demand and would not create an impact. No mitigation would be necessary for this minor change in parking supply.

Replacement Alternatives. Each of the East Span Replacement Alternatives would eliminate between 6 and 8 informal parking spaces in the paved area east of Quarters 1. Given the large undeveloped area available for parking, the loss of this small number of parking spaces would not contribute to unmet parking demand and would not create an impact. No mitigation would be necessary for this minor change in parking supply.

There would be no long-term loss of parking spaces under any of the project alternatives.

The potential for ship collisions with the East Span alternatives has been evaluated. Effects of impacts to the structures from vessel types likely to use the waters under the bridge are presented here.

Information regarding type, size, and frequency of vessels that use the shipping channel east of YBI was collected to determine vessels likely to pass under the East Span in open water. The largest vessel currently using the east navigation channel is a fuel barge.

American Association of State Highway and Transportation Officials (AASHTO) specifications were used to estimate impact loads on towers and piers. Head-on and side impact collisions were considered. To evaluate worst-case impacts, it was assumed that cruise ships could use the east channel under potential development scenarios for TI. The vessel’s speed, mass, and crushing of its hull were considering in developing impact loads. Cruise ships, being larger than existing barges using the east navigation channel, would generate the largest impact loads.

The No-Build Alternative would not modify the existing East Span and would not change navigation patterns through the existing shipping channel. No modifications to the bridge are proposed under this alternative; therefore, no modifications would be constructed to minimize impacts of future ship collisions.

The Retrofit Existing Structure Alternative would strengthen existing piers in the navigation channel, shorten spans, increase the ability of the structure to withstand impact from a maximum-design cruise ship at the main span piers and impacts of barges at the shorter span piers. More piers would increase the likelihood of a collision between a vessel and a pier. The additional piers would also narrow the existing navigation channel. The alternative would maintain a width of at least 152 meters (500 feet) between piers in the navigation channel and a vertical clearance of 42 meters (138 feet) over mean high water, and the resulting channel width would conform to USCG standards.

As part of bridge design, protective fenders are proposed at the main tower and skyway piers to provide sufficient standoff to prevent vessels from hitting pier columns and reduce pile cap damage on impact. The fenders could be either pile-supported or pile cap-mounted. One possible fender system would have a timber-rubbing face and remains elastic up to a particular level of impact energy. Beyond this level, it absorbs energy by damage to the concrete and timber, but is designed to be easily repaired. The system also provides a wearing surface on the pier for minor collisions and bumps from merchant and recreational vessels.

In reviewing bridge designs, all skyway foundations were found to be able to withstand the impact of a light drifting barge, and skyway piers would be able to withstand the maximum-design barge impact. The main towers and skyway pier foundations would be capable of sustaining impacts for the maximum-design cruise ship.

No potential for significant damage to project alternatives has been identified, due to design of piers and fender systems, and no mitigation is required.

Each of the replacement alternatives would narrow the existing navigation channel. The replacement alternatives would maintain a width of 152 meters (500 feet) between piers in the navigation channel and a vertical clearance of 42 meters (138 feet) over mean high water, and the resulting channel width would conform to USCG standards. The project would install all applicable navigation aids, such as fenders and lights.

The No-Build and Retrofit Existing Structure Alternatives would not change the location or height of towers and would not require changes to obstruction markings or lighting to alert aircraft to the presence of the existing East Span.

The replacement alternatives would change existing obstruction markings and lighting. FAA Form 7460-1, "Notice of Proposed Construction or Alteration," would be filed with the FAA. The form, to be filed following selection of the preferred alternative, would disclose the location and height of a cable-supported tower (if selected). Because main span towers proposed with replacement alternatives, cable-stayed and self-anchored suspension design variations would exceed 61 meters (200 feet) in height, warning lights atop the tower would be required.

The following section describes the visual effects of the various project alternatives on each of the landscape units which make up the project area, as well as the changes in visual quality that would be experienced from the 17 representative viewpoints around the Bay Area. In addition, the changes in visual quality for motorists traveling on the East Span are also discussed.

The change to each of the five landscape units was assessed for each of the four build alternatives and a number of design variations. The impact on landscape units and visual image types is evaluated for the period when the bridge is in full operation. Each landscape unit would be affected differently according to the combination of these alternative/design variations.

Retrofit Existing Structure Alternative. The retrofit alternative would not require alteration of visual features on the island. Operation period would be identical to what exists today. All visual image types within this landscape unit would remain intact. Adding substantial structural members on the outside of the cantilever superstructure would add clutter and mass to existing bridge.

Skyway/Signature Bridge Design Variations. Following the construction and dismantling of the existing bridge, the Yerba Buena Island landscape unit would appear altered by the removal of portions of the woodland area to the north and/or south of the span. The width of the bridge itself would also be altered because the side-by-side, single-deck roadway design would be double the width of the existing span.

Replacement Alternative S-4 would reduce the size of the USCG facilities, although the structures that could be removed are not currently visible from the existing span. Similarly, Replacement Alternatives N-6 and N-2 would reduce the image type represented by removing Buildings 40, 75, and 270. These structures are not currently visible from the existing span.

The most substantial alteration of this landscape unit would occur through the removal of woodland vegetation that would require a number of years to reestablish itself. It is probable, depending on the amount of clearing required, that residential structures currently obscured by the vegetation would become visible.

Retrofit Existing Structure Alternative. Following the seismic strengthening measures, the landscape unit would reflect a slight increase in view blockage as a result of the introduction of two new piers. This would not be considered a substantial visual impact. The Bay would remain the predominant visual image type within this landscape unit.

Skyway Bridge Design. Following the construction and dismantling period, this landscape unit would appear much different. The bridge design would exhibit a much narrower profile than the existing structure because the cantilever element would not be present. In addition, the bridge would be a single-deck rather than a double deck roadway. The steel cross beams that extend from the upper to lower deck on the existing structure would no longer be present. The skyway design variation profile would consist of a simple concrete sidewall along either side of the deck, reading like a ribbon from points north and south. The predominant visual image type within this landscape unit would be the Bay.

With Replacement Alternatives S-4 and N-6, views toward the skyline of San Francisco would be expanded for westbound travelers, while Replacement Alternative N-2 would produce views similar to the existing span. Eastbound travelers would experience expansive views toward the Port of Oakland and toward the hills above the communities of Oakland, Berkeley, and Alameda, although visibility to the south would be reduced by the presence of a 4.7-meter (15.5-foot) wide bicycle/pedestrian lane.

Signature Bridge Design Variation. Following the construction and dismantling period, the landscape unit would be dominated by a much taller and different signature tower element. The contrast between the existing cantilever and truss elements and the proposed single tower element would be dramatic. The bridge would also be modified through the removal of the double deck roadway. The single deck, side-by-side roadway would produce a much narrower profile, and the image of the bridge would be sleeker and lighter, because there would no longer be steel beams connecting the upper and lower decks. The predominant visual image type would remain the Bay.

As with the skyway design variation, the S-4 and N-6 Replacement Alternatives would produce expanded views toward the skyline of San Francisco for westbound travelers, while Replacement Alternative N-2 would produce an effect similar to the existing span. Eastbound travelers would experience expansive views toward the Port of Oakland and toward the hills above the communities of Oakland, Berkeley, and Alameda, although views to the south may be compromised by the presence of a 4.7-meter (15.5-foot) wide bicycle/pedestrian lane.

Retrofit Existing Structure Alternative. The retrofit alternative would produce the least amount of change from the existing span. The span would continue to have two bridge decks connected by steel beams. The predominant visual image type of the incline section would remain the Bay. No change in the SFOBB’s alignment would occur, the bridge would appear visually much as it does today.

Skyway/Signature Bridge Design Variations. Both the skyway and the signature bridge design variations would provide a skyway deck along this portion of the span. The greatest change to this landscape unit involves the replacement of the existing double deck structure with side-by-side single decks. The effect of this change would be that the bridge would more than double in width, while the height of the deck area would be reduced. Views from the bridge would expand because of the reduced height of the bridge rail, which would facilitate views from passenger vehicles, and absence of the upper deck for eastbound motorists. The predominant visual image type of this section of the bridge would remain the Bay.

Replacement Alternative S-4 would offer the greatest change in viewshed as it follows a more southerly alignment, while Replacement Alternatives N-6 and N-2 remain closer to the SFOBB’s existing alignment along this section of the bridge. Views to the south, however, may be compromised by the presence of a 4.7-meter (15.5-foot) wide bicycle/pedestrian lane.

Retrofit Existing Structure Alternative. The retrofit alternative would produce the least amount of change from the existing span. The visual image types currently present at the touchdown area would not be altered with the implementation of the retrofit alternative. The alignment of the East Span would not change and additional right of way would not be required for its construction. The predominant visual image types would remain marsh and estuary areas and light industrial.

Skyway/Signature Bridge Design Variations. Replacement Alternatives N-6 and N-2 would require construction within a portion of the area designated for resource conservation by the City of Oakland to the north of the existing span. Replacement Alternative S-4 would require construction within most of the undeveloped and light industrial land to the south of the existing span. The result of this change in the SFOBB’s existing alignment would be a reduction in the visual image type (marsh, estuary, and light industrial) associated with the land taken by the replacement alternatives.

The bridge itself would produce a much narrower profile and would be a lighter, more streamlined structure. The steel cross beams that currently extend between decks would not be present, and the single decks would be placed side-by-side rather than stacked one on top of another. Views from the structure would be similar to what exists today as the bridge at this point is rejoining the SFOBB’s existing alignment as it approaches the toll plaza. Views to the south, however, may be compromised by the presence of a 4.7-meter (15.5-foot) wide bicycle/pedestrian lane.

The toll plaza area would not undergo substantial change as a result of the project. The proposed replacement alternatives would rejoin the existing roadway at the toll plaza. The location of the toll booths would not change, and the realignment of the roadway to the north or south would not substantially affect the existing visual appearance of this landscape unit. Because of the level topography of the toll plaza, views from the roadway to the Bay and to the Port of Oakland would remain open and virtually unobstructed as vehicles proceed westward along the touchdown area toward the incline section of the span.

The following section describes the visual changes that motorists traveling on the SFOBB East Span would experience under the retrofit and replacement alternatives. To aid in this evaluation, an animation of the motorists’ view was created for the replacement alternative signature bridge design variation. Still pictures of key views from this animation are presented in this section (see Figures 4-2 to 4-4 in Appendix A). The animation is provided on a CD-ROM included in the Visual Impact Assessment Report which can be reviewed at locations identified in the Preface and on the worldwide web at www.dot.ca.gov/dist4.

The retrofit alternative would only slightly change motorists’ views from the existing East Span. The current double-deck structure would be maintained, including its solid steel sidewalls that block some motorists’ views of the Bay. Steel crossbeams that extend from the upper to the lower deck would be modified to permit large displacements at specified joints. As a result, views would continue to be restricted, especially in the eastbound direction, where the presence of the westbound deck overhead results in a further obstruction to the viewshed. Adding substantial structural members on the outside of the cantilever superstructure would add clutter and mass to existing bridge.

The skyway design variation would result in substantial changes to the motorists’ view, because it would create side-by-side roadway decks with sidewalls and railings designed to facilitate views from the structure. Because the skyway design variation would not include a signature structure, views would remain unobstructed throughout the length of the East Span.

Although views from the East Span with the skyway design variation would be greatly expanded, three design issues would have an effect upon the extent of views from the structure. First, the roadways would be placed side by side. The effect of side-by-side roadways would be that a viewer would have a five-lane roadway in the foreground of their view to the north (when traveling in the eastbound direction) or south (when traveling in the westbound direction). (See Figures 4-2 to 4-4 in Appendix A). Second, the addition of a 3-meter (10-foot) shoulder on each side of the roadway further expands the structure in the motorists’ foreground view. Finally, the creation of a 4.7-meter (15.5-foot) wide pedestrian/bicycle path on the south side of the eastbound bridge deck would affect views southward from the East Span. The bicycle and pedestrian lane would be raised 0.3 meter (1 foot) above the flow of auto traffic, further restricting views to the south.

When comparing Replacement Alternatives, N-6 and S-4 would expand westbound views toward the City of San Francisco because of their distance from the existing East Span, which would allow views around YBI. Replacement Alternative N-2 would expand views to a lesser degree because it closely follows the alignment of the existing East Span.

The signature bridge design variation would also expand views from the East Span because, as with the skyway design variation, the East Span would be constructed with side-by-side roadways, sidewall features, and railings to facilitate views from the structure. The signature structure and cables would somewhat obstruct views as vehicles pass through the main span section. However, overall views would increase greatly when compared with the existing structure.

The design issues noted above for the skyway design variation would have a similar effect on views from the signature structure. The creation of side-by-side single decks, the addition of 3-meter (10-foot) shoulders, and the construction of a 4.7-meter (15.5-foot) pedestrian/bicycle path would restrict views from the East Span to the north and south. Figures 4-2, 4-3, and 4-4 in Appendix A depict a motorist’s view while driving on the signature bridge variation.

When comparing Replacement Alternatives, N-6 and S-4 would expand westbound views toward the City of San Francisco because their distance from the existing East Span would allow views around YBI. Replacement Alternative N-2 would expand views to a lesser degree, because it would closely follow the alignment of the existing East Span.

The changes in visual quality due to the project alternatives have been analyzed from 17 viewpoints around the Bay Area, as described in Section 3.3.3. Generally, the changes that would occur with each of the various project alternatives and design variations would be similar from each of the viewpoints. The analysis from four viewpoints has been included in this report to represent the changes in visual quality from each location. These viewpoints are Richmond (from the north), the Oakland Touchdown area (from the east), the Oakland-San Francisco Ferry (from the south), and Treasure Island (from the west). This analysis, which includes computer-generated visual simulations, follows.

The retrofit alternative would have a negligible effect on visual quality from distant viewpoints, because the structural elements added to the East Span would not be perceptible. For some of the closer viewpoints, the retrofit alternative would have a minimally adverse effect on viewers, as the additional structural elements (new piers and strengthening of existing piers) would obstruct views underneath the bridge.

The signature bridge design variation would result in the most favorable effect upon visual quality regardless of the viewpoint location. Typically, this is due to the increase in the vividness of the span and the overall unity that would occur with the signature bridge design variation. While conditions would vary at individual viewpoints, overall, the three replacement alternatives (N-2, N-6, and S-4) would result in virtually identical visual effects.

The skyway design variation would result in the greatest reduction in visual quality. Typically, this effect would be due to a reduction in the vividness and intactness of the span caused by the simpler structure and thinner bridge deck. While conditions would vary at individual viewpoints, overall, the alignments of the three replacement alternatives under the skyway design variation would result in virtually identical visual effects.

Retrofit Existing Structure Alternative. The retrofit alternative would have a negligible effect on visual quality. The long distance from this viewpoint to the East Span would make changes to the piers and support structures imperceptible.

Skyway Design Variation. The skyway design variation would have a minimally adverse effect on visual quality, due to its reduction in vividness (see Figure 4-5 in Appendix A). While it would remain at a favorable viewing angle, the simplicity of the structure would eliminate the striking and distinctive nature of the existing East Span.

Signature Bridge Design Variation. The signature bridge design variation would have a minimally beneficial effect on the visual quality of the view towards the East Span, due to the increase in vividness (see Figure 4-6 in Appendix A). The signature tower would add landmark strength and distinctiveness, but the distance between the viewpoint and the East Span would make its distinct elements difficult to discern.

The signature bridge design variation would have a beneficial effect on the overall visual quality from the Richmond Marina, due to the increase in the vividness of the East Span and overall unity of the view. Unity would increase the greatest amount (from moderate-to-high to high) for the suspension bridge design variation, due to the visual similarity, prominence, and shape, compared with the SFOBB West Span (which would be visible from the vantage point). Unity would increase less (remaining at moderate-to-high) with the cable-stayed bridge design variation, because its shape would not echo the catenary forms of the SFOBB West Span.

Retrofit Existing Structure Alternative. The retrofit alternative would result in a minimally adverse effect on visual quality of the view toward the East Span, due to the increase in view obstruction. New support piers and other structural elements added as part of the retrofit alternative would decrease views beneath the East Span.

Skyway Design Variation. The skyway design variation would result in a minimally adverse effect on visual quality, due to the slight decrease in the vividness of the East Span (although the East Span’s close proximity and prominence mean vividness would still remain high) (see Figure 4-7 in Appendix A). In addition, with Replacement Alternatives N-2 and N-6 there would be a slight increase in view obstruction. These alternatives would provide views similar to the existing East Span, although its more gradual rise from west to east would obstruct views from beneath the East Span to the north.

Signature Bridge Design Variation. The signature bridge design variation would result in a minimally beneficial effect on visual quality of the view toward the East Span, due to the increase in vividness (see Figure 4-8 in Appendix A). The signature structure would add landmark strength and distinctiveness. Vividness would increase the most with Replacement Alternatives S-4 and N-6, because the signature structure would be at a more favorable viewing angle (closer to 45 degrees) than Replacement Alternative N-2.

The signature bridge design variation would result in a minimally beneficial effect on visual quality of the overall view from the Oakland Touchdown area, due to an increase in vividness and unity (which are already at high levels) and the fact that the East Span occupies much of the larger view. There would be less of an increase in unity with Replacement Alternative S-4, because portions of the SFOBB West Span would become visually obstructed. Unity would increase more with the suspension bridge design variation, due to the visual similarity, prominence and shape compared with the SFOBB West Span and Golden Gate Bridge (which would be visible from the vantage point). Unity would increase less with the cable-stayed bridge design, because its shape does not echo the catenary forms of the SFOBB West Span.

Retrofit Existing Structure Alternative. The retrofit alternative would result in a negligible effect on visual quality. New support piers and other structural elements added as part of the Retrofit Alternative would decrease views beneath the East Span. However, views beneath the East Span would be constantly changing as the ferry continues its route, thereby minimizing the view obstruction created by the new piers and structural elements.

Skyway Design Variation. The skyway design variation would result in a minimally adverse effect on visual quality, due to the decrease in its vividness (see Figure 4-9 in Appendix A). While it would remain at a favorable viewing angle and would be relatively close, the simplicity of the skyway design variation would reduce the distinctive nature of the existing East Span. The reduction in the vividness would be less perceptible with Replacement Alternative S-4, because it is the closest Replacement Alternative to this viewpoint. Vividness would reduce the most with Replacement Alternative N-6.

Signature Bridge Design Variation. The signature bridge design variation would result in a minimally beneficial effect on the visual quality of the view toward the East Span, due to the increase in its vividness (see Figure 4-10 in Appendix A). The signature structure would add landmark strength and distinctiveness to the East Span. When comparing replacement alternatives, vividness would be most increased with Replacement Alternative S-4, because it is nearest to this viewpoint.

The signature bridge design variation would result in a minimally beneficial effect on the overall visual quality of the view toward the East Span, due to the increase in its unity and vividness. The close proximity and visual dominance of the East Span mean that changes to it would substantially affect the overall visual quality of the larger view. Unity would increase more with the suspension bridge design variation, due to the visual similarity, prominence and shape compared with the SFOBB West Span (which is visible from this viewpoint). With the cable-stayed bridge design variation, unity would increase over existing conditions but less than with the suspension bridge design variation, because its shape does not echo the catenary forms of the SFOBB West Span.

Retrofit Existing Structure Alternative. The retrofit alternative would result in a minimally adverse effect on visual quality. This effect is due to the increase in view obstruction from addition of shear walls on support structures under the bridge toward the City and Port of Oakland (see Figure 4-11 in Appendix A).

Skyway Design Variation. The skyway design variation would result in a minimally adverse effect on the visual quality of the view toward the East Span (see Figures 4-12 and 4-13 in Appendix A). With Replacement Alternative N-6, this decrease would be due to reduced vividness (these effects are somewhat offset by improved views over the East Span) and minor community disruption/privacy infringement issues because the replacement alternative would be closer to Treasure Island. With Replacement Alternative N-2, the reduction in visual quality would be due to the reduced vividness. With Replacement Alternative S-4, any reduction in visual quality would be due to reduced vividness and additional view obstruction caused by the way the piers would align. These effects are somewhat offset by a reduction in community disruption/privacy infringement because the East Span would be farther away.

The skyway design variations would result in a minimally adverse effect on the overall visual quality from Treasure Island. The close proximity and visual dominance of the East Span within the larger view mean that changes to it would substantially affect the overall visual quality. The reasons for the reduction in overall visual quality are the same as those cited in the preceding paragraph.

Signature Bridge Design Variation. The signature bridge design variation would result in a minimally beneficial effect on the visual quality of the view toward the East Span (see Figures 4-14 and 4-15 in Appendix A). With Replacement Alternative N-6, this effect would be due to the increase in the vividness of the East Span and the decrease in view obstruction (these effects are somewhat offset by the increase in community disruption/privacy infringement because it is closer to activities on Treasure Island). With Replacement Alternative N-2, this effect would be due to the increase in vividness. With Replacement Alternative S-4, this effect would be due to the increase in vividness and the reduction in community disruption/privacy infringement (these effects are somewhat offset by the increase in view obstruction).

The signature bridge design variation would result in a minimally beneficial effect on the overall visual quality from Treasure Island. Because the East Span occupies much of the larger view from this viewpoint, changes to it would have a substantial effect on the overall visual quality. As a result, there would be a minimally beneficial effect on overall visual quality from this viewpoint (see prior discussion).

All three replacement alternatives would require the removal of substantial amounts of woodland vegetation (approximately 325 to 364 trees from 15 centimeters to 1.8 meters [6 inches to 6 feet] in diameter) within the project’s construction limits on YBI. A large grove of mature trees, primarily Eucalyptus, would be removed from the east-facing slopes of the island to accommodate any of the proposed replacement alternatives and associated detour spans. The average height of the trees is 12 meters (39 feet), and the visual effect of the trees is dramatic. They soften the island’s appearance from a distance and screen a number of residences on the island.

All three replacement alternatives would require the removal of a number of trees within the project’s construction limit on the Oakland Touchdown area. Replacement Alternatives N-6 and N-2 would necessitate the removal of 71 mature trees. Replacement Alternative S-4 would necessitate the removal of 12 mature trees.

The removal of this vegetation on both YBI and the Oakland Touchdown area would constitute a substantial visual impact, and a number of years would be required before the vegetation could reestablish itself to the density that exists today. The loss of this many trees would be highly noticeable during the construction period and subsequent years until the vegetation has reestablished itself. Views from the bridge as well as views from the East Bay would be affected by the removal of this vegetation. Table 4.3-1 includes the amount of total area disturbed and number of trees removed by alternative.

Mitigation. Mitigation for visual impacts associated with YBI will consist of development of a master planting plan developed in cooperation with local city agencies in accordance with the Treasure Island Draft Reuse Plan (TIDRP). It may not be appropriate, considering the fact that the eastern side of the island is expected to have a more urban character under the TIDRP, to simply replant the affected areas to replicate their former state. The TIDRP calls for the shorelines of TI and YBI to be more publicly oriented with garden parks along the shoreline. Mitigation will reflect this proposed new context.

Mitigation for visual impacts associated with the Oakland Touchdown area will consist of development of a master planting plan developed in cooperation with local city agencies. In addition, public access provided as mitigation for impacts associated with the Cypress Replacement Project (discussed in Section 6.7.1) will be included as part of this project.

Source: Caltrans, August 1998.

Implementation of Mitigation Measures. A master plan and aesthetic guidelines for careful planning and development of the project’s construction limit will be prepared by Caltrans in cooperation with the local city and county agencies and any community groups who have an interest in the project. Separate plans and guidelines will be developed for YBI and the Oakland Touchdown area.

All the proposed alternatives would maintain five lanes of traffic in both directions on the East Span during and after construction and would not affect traffic volumes on or capacity of the bridge and adjacent freeways. As such, there should not be any change in air pollutant emissions due to any of the proposed alternatives compared to a No-Build condition.

However, a possible air quality issue does arise with the replacement alternatives, each of which includes a pedestrian/bicycle path. Users of a pedestrian/bicycle path would be located adjacent to the bridge roadway. A microscale carbon monoxide (CO) analysis was conducted to ensure that sufficient consideration was given to the preservation of air quality along areas of the bridge that might be used for a pedestrian/bicycle path.

This section considers the potential for exceeding state and federal ambient air quality standards for CO along the proposed pedestrian/bicycle path due to project operations. Short-term air quality impacts during construction are discussed in Section 4.14.

A microscale dispersion analysis of CO emissions was performed using the EMFAC7F emission factor model and CALINE4 dispersion model. Traffic along a typical replacement structure was modeled under year 2005 conditions to determine CO concentrations 5.5 meters (18 feet) from the outside edge of the travel lanes, representing the center of a pedestrian/bicycle path. There would be no other public receptors in the immediate vicinity of the bridge span.

Background concentrations for the year 2005 were determined to be 1.9 parts per million (ppm) for one-hour average and 1.3 ppm for eight-hour average. These background concentrations were determined using Bay Area Air Quality Management District (BAAQMD) isopleth maps and rollback factors. Isopleth maps are maps that show contour lines of carbon monoxide concentration. The contours are based on monitoring data and can be used to interpolate concentrations where there are no monitoring stations. Rollback factors are used to reduce current CO background levels as an estimate of future levels. It is assumed that CO levels will decline in the future because newer motor vehicles will have better emission controls.

4.4.2 Impacts

Worst-case one-hour and eight-hour average CO concentrations (project roadway contribution plus background concentration) predicted by the CALINE4 model are 2.7 ppm for a one-hour average and 1.9 ppm for an eight-hour average. These values are well below the federal and state standards. Federal one-hour and eight-hour standards are 35 ppm and 9 ppm, respectively. State standards are 20.0 ppm for one-hour and 9.0 ppm for eight-hour. In conclusion, neither state nor federal CO standards would be exceeded on the pedestrian/bicycle path regardless of location.

4.4.3 Air Quality Conformity

A microscale CO analysis was conducted for the project to determine project level conformity to the SIP as required by EPA’s Transportation Conformity Rule. The analysis assumptions were developed in coordination with MTC and are consistent with assumptions used in the regional emissions analysis for the RTP and TIP for those inputs required in both analyses. The analysis shows that there are no CO violations expected in the project area. Since the Bay Area is not considered a federal PM₁₀ non-attainment area, PM₁₀ conformity requirements in the Transportation Conformity Rule are not applicable.

Based on the above information, it is concluded that the East Span Project is in conformity with the SIP.

Noise abatement measures are also discussed for each alternative. The need for noise abatement and the nature and form of noise abatement measures are important considerations for the East Span Project because of unique issues associated with its location. Noise abatement measures (e.g., construction of a noise barrier) are to be considered for reducing noise impacts when the predicted peak-noise-hour levels approach or exceed FHWA Noise Abatement Criteria (NAC) for appropriate land use categories (see Table 3.5-1). For this project, noise abatement measures were considered and evaluated for effectiveness based upon the FHWA NAC.

Although soundwalls are the most reliable and commonly accepted method of reducing roadway or bridge-generated noise levels, other approaches to noise abatement will be investigated during final design of the selected alternative. Noise abatement approaches that would not restrict views of bridge users or detract from bridge aesthetics will be considered by Caltrans for effectiveness during final design of the selected alternative (see Abatement Options for Noise Abatement Materials and Treatment section following).

Yerba Buena Island. Soundwalls which would reduce noise levels 5 dB or more and break truck-stack line-of-sight at YBI are the same for Replacement Alternative S-4 as for Replacement Alternative N-2. (See Table 4.5-4 in this section and Figure 4-18 in Appendix A for recommended soundwall locations for Replacement Alternative S-4.)

4.6.2 Summary and Comparison of Alternatives

Tables 4.6-1 and 4.6-2 and the following subsections summarize and compare potential impacts by alternative for the YBI and Oakland Touchdown areas, including detour options. The discussion focuses on potentially contaminated sites discussed in Section 3.6 and identified on Figures 3-15a and 3-15b in Appendix A.

Table 4.6-1 Comparison of Alternatives: Contaminated Sites

2 Impact unknown as no sampling has been conducted around the maintenance facility.

Contaminated Sites

construction traffic under dry, dusty conditions would include direct worker contact through ingestion or dermal contact. Although pesticides and semi-volatile organic compounds (SVOCs) were also detected in this area, a baseline human health risk assessment conducted in 1996 determined that the only potential concern was exposure to beryllium and lead.

Fuel Lines, Building 213 - Petroleum hydrocarbon contamination beyond the fuel oil line trenches could affect the soils near the base of the piers in this area (See Figure 3-15a in Appendix A).

• SFOBB Structure - Historic use of lead-based paint on the bridge structure will be of concern during bridge retrofitting activities. Concerns include both those associated with worker health and safety and handling and disposal of contaminated materials.

• IR Site 11, Former Landfill - Groundwater may be encountered if construction of the temporary east entrance to the USCG should exceed the depth of 1.6 meters (5.4 feet) to 3.2 meters (10.6 feet) below ground surface.
• IR Site 29, East Side Contaminated Bridge Soils - During removal of existing piers and construction of new piers, workers may encounter soils contaminated by metals associated with past bridge maintenance and operations and also by petroleum hydrocarbons.
• IR Site 8, Former Army Point Sludge Disposal - During construction located immediately north of the existing SFOBB, exposure pathways to metals (especially beryllium and lead) due to heavy construction traffic under dry, dusty conditions would include direct worker contact through ingestion or dermal contact. Although pesticides and semi-volatile organic compounds (SVOCs) were also detected in this area, a baseline human health risk assessment conducted in 1996 determined that the only potential concern was exposure to beryllium and lead.
• Fuel Lines, Building 213 - Petroleum hydrocarbon contamination beyond the fuel oil line trenches could affect the soils near the base of the piers in this area (see Figure 3-15a in Appendix A).
• Building 270 LUST Site - Construction of a temporary detour above Building 270 may be affected by elevated concentrations of TPH/diesel in soils and the groundwater petroleum hydrocarbon plume associated with the leaking underground storage tank at this building.
• Building 204/208 LUST Site - Construction of replacement alternatives may affect a possible source of contamination at the Building 204/208 site. The former fire station/gas station site appears to be located upgradient from Building 270 (referenced above) and may be a possible source of groundwater contamination identified in the groundwater monitoring well immediately upgradient of Building 270.
• Building 40 LUST Site - Foundation, piers, or the relocated USCG access roadway would be located on ground currently occupied by Building 40, and footings for the detour spans may also occupy a portion of the ground surface of the building.
• SFOBB Structure - Historic use of lead-based paint on the bridge structure would be of concern during bridge demolition activities. Concerns include both those associated with worker health and safety and handling and disposal of contaminated materials.

The plan would specify mitigation of potential worker and public exposure to airborne contaminants by incorporating dust suppression techniques in construction procedures.