Meeting_Body
CONSTRUCTION COMMITTEE
JUNE 21, 2018
Subject
SUBJECT: WESTSIDE PURPLE LINE EXTENSION
PROJECT ENVIRONMENTAL IMPACT REPORT
ADDENDUM
Action
ACTION: APPROVE RECOMMENDATIONS
Heading
RECOMMENDATION
Title
CONSIDER:
A. APPROVING project definition changes, and Environmental Impact Report (EIR) Addendum (Attachment A) for the Westside Purple Line Extension Project (the Project); and
B. AUTHORIZING the Chief Executive Officer to file a Notice of Determination (Attachment B) on the Addendum pursuant to the California Environmental Quality Act (CEQA) for the Project.
Issue
ISSUE
On May 24, 2012, the Metro Board certified the joint Final Environmental Impact Statement/Environmental Impact Report (FEIS/FEIR) (State Clearinghouse No. 2009031083) for the Project and approved the Project Definition, Findings of Fact and a Statement of Overriding Considerations under CEQA. Since then, Metro has completed Advanced Preliminary Engineering for the Project and conducted additional stakeholder outreach and coordination for the portion of the Project that extends from Century City to the Westwood/Veterans Affairs (VA) Campus (referred to as Section 3 of the Project). These efforts have introduced a limited number of refinements to project features and construction methods that improve long-term operational efficiency and minimize previously identified impacts.
Pursuant to CEQA Guidelines Section 15164, Metro has analyzed potential environmental impacts of the refinements and concluded that an Addendum is appropriate. The Addendum finds that none of the changes associated with the refinements represent substantial changes to the Project, generate new significant impacts, or result in previously identified significant effects becoming substantially more severe than shown in the FEIS/FEIR. This includes consideration of potential long-term (operational), short-term (construction), and cumulative impacts.
Discussion
DISCUSSION
The principal project definition changes to the Project since completion of the 2012 FEIS/FEIR include the following:
• VA/Army Reserve Construction Staging Areas
Construction staging areas identified on or in proximity to the Veterans Affairs West Los Angeles (VA WLA) Campus have been refined since the issuance of the FEIS/FEIR. The FEIS/FEIR considered two options for the location of the construction staging area for the Westwood/VA Hospital Station: 1) within the parking lot south of Wilshire Boulevard and east of Bonsall (Lot 42) and 2) a staging area partially on the U.S. Army Reserve site and partially on the western side of the VA WLA Campus (referred to as the U.S Army Reserve site). As explained in the FEIS/FEIR, the U.S. Army Reserve site would be used if Lot 42 is unavailable at the time of project construction.
As of April 30, 2018, locating a portion of the construction staging area on the U.S Army Reserve is no longer a viable option to support tunneling operations. Therefore, Metro, in coordination with VA WLA staff, proposes a construction staging area on the western portion of VA WLA Campus for tunneling operations (the staging area in Lot 42 would still be required to support construction of the station box). The staging area would largely be in the same location as what was identified on the western side of the VA WLA Campus in the FEIS/FEIR. The size of the staging area on the VA WLA Campus would increase from 1.7 acres as identified in the FEIS/FEIR to approximately 3.3 acres (an increase of 1.6 acres) because the portion of the staging area on the U.S. Army Reserve site would be eliminated. Compared to the FEIS/FEIR, the construction staging area can accommodate the major construction activities. This construction staging area also enables the contractor to place construction equipment in locations that minimize noise at nearby sensitive receivers and minimize truck queuing, thereby reducing impacts to the VA Hospital and its patrons.
• Alignment and Crossover Tracks
The location and alignment of the subway station and tunnels have been shifted south within the VA Hospital Parking Lot 42 south of Wilshire Boulevard by approximately 150 feet. The shift in the station box required refinements to the station entrance and pedestrian circulation features. This refinement of the alignment will accommodate a crossover track directly east of the Westwood/VA Hospital Station. This location is operationally preferable compared to the previous location at the West LA Federal Building, separated from the station, on the east side of the I-405 Freeway. The GSA crossover will be eliminated and construction staging on the surface of the West LA Federal Building property will no longer be necessary. In addition, the Caltrans staging area necessary for grout injection to support utilities beneath Sepulveda Boulevard has been reduced by 0.78 acres (from 1.72 to 0.94 acres) because these construction activities can be accommodated with a smaller staging area than what was required for the crossover. The benefits are less disruption, noise and vibration, haul route activity, and traffic in front of the West LA Federal Building.
• Westwood/VA Hospital Station Access
A formal passenger drop-off area is proposed on the south side of Wilshire Boulevard within the existing VA Hospital parking lot just east of the proposed station plaza and entrance (Lot 42). The passenger drop-off area would have approximately 40 spaces for short-term parking (15-30 minutes) and include lighting and traffic islands. The provision of a dedicated passenger drop-off /pick-up area would benefit the VA West LA Campus and the veteran community as it is designed to discourage Metro passengers that are not associated with the VA from being dropped off or picked up in other parts of the VA West LA Campus. As part of this refinement, a bus layover for future bus service would be provided on the westbound on-ramp from Bonsall Avenue to Wilshire Boulevard.
• Construction Method for Westwood/VA Hospital Station West Crossover
The refined alignment includes a longer crossover section west of Bonsall Avenue under the lawn area, approximately 250 feet long. With the refined alignment, the tunnels are excavated in advance of the crossover. Geotechnical investigations completed since the FEIS/FEIR for the refined alignment confirmed sands and clay of the younger and older alluvium are present. These “soft ground” soils are less favorable for the sequential excavation mining method identified in the FEIS/FEIR and would increase construction risks, including schedule impacts and worker safety. As such, Metro proposes constructing the crossover via a cut-and-cover method, similar to the rest of the station structure.
• Bonsall Avenue Underpass Murals
Studies conducted since the completion of the FEIS/FEIR indicate that the removal of one of the art murals along the Wilshire Boulevard off-ramp to Bonsall Avenue would be required for construction of the station pedestrian circulation elements. Once stairs and escalators are constructed, there would not be sufficient space to accommodate the mural wall in its present location. The current murals are starting to fade due to the type of paint that was used; therefore, Metro has developed a plan to replicate this mural in a reduced-scale version using a more durable medium of mosaic tile. The mosaic would be located across from the current location of the northeast mural wall in an embankment and retaining wall. Reconfiguration of the mural into a mosaic is subject to the approval of the LA County Arts Commission and the LA County Board of Supervisors and an agreement is required by Los Angeles County to maintain the mosaic in perpetuity. Metro has been coordinating the proposal with the VA, veterans groups, and other stakeholders.
• Westwood/UCLA Station Entrance
The project definition that was approved in the FEIS/FEIR included a station entrance on the northwest corner of Wilshire and Westwood Boulevards that required the construction of mined tunnels beneath the existing Westwood Medical Building with an entrance inside a parking garage to the north of that building. This would impact basement levels of the Westwood Medical Building and require transit patrons to use narrow sidewalks along Westwood Boulevard to access the station entrance. In the course of further design, Metro worked with the City of Los Angeles and the property owner to integrate a larger station entrance into an existing one-story bank building in a way that would preserve the historic integrity of the building and utilize an existing pedestrian plaza to provide significantly improved pedestrian access to the station.
• Subway Tunnel Diameter
The size of the bored subway tunnels for Section 3 has been increased from an outside diameter of 20 feet 10 inches to 22 feet 6 inches to accommodate portions of the crossover at the Westwood/VA Station and thereby reduce the size of the cut-and-cover excavation. The distance between the tunnels has been reduced to keep the tunnels within the subsurface easement areas identified in the FEIS/FEIR. The larger tunnels would reduce the length of the station box cut-and-cover excavation by approximately 50 feet at each crossover. As a result, the station would not extend into the I-405 off-ramp near the east end of the station and the easement area required by the WLA VA Historic District on the west end of the station box would be reduced.
• Grouting in Century City
Geotechnical studies completed in support of the advancement of the design indicate that ground improvement (grouting) may be required in Century City beneath the Westfield Mall to minimize tunneling ground settlement and insure ground stability near the intersection of Century Park West and Constellation Boulevard. Necessary grouting would occur using shafts located within Century Park West and/or Constellation Boulevard. Ground improvement is also proposed at Sepulveda Boulevard from below the level of existing utilities to below the bottom of the tunnels to protect the utilities as the tunnels pass beneath them. Several major utilities are in this location, some of which are very deep. Grouting at this location would be provided from a shaft located within Caltrans right-of-way and street closures would not be required.
• Underground Conduits
Metro is coordinating with Southern California Edison (SCE) to install a new power line for construction activities, including the power required for station construction and operation of the Tunnel Boring Machines, from the Sawtelle substation to the WLA VA Campus construction site, a distance of approximately 0.76 miles, then a further distance of 0.3 miles to the new station. This new power line, which would be within the public right-of-way, is still being designed and is expected to use existing SCE overhead infrastructure for a small portion of the route, as well as new underground conduits constructed by Metro. A secondary (emergency) power source would be provided from the existing SCE Colorado substation, as Metro requires two independent sources for reliability. The majority of the line will use existing overhead SCE infrastructure and will require a similar length of underground conduits as the primary power route.
Determination_Of_Safety_Impact
DETERMINATION OF SAFETY IMPACT
This Board action will not have an impact on established safety standards.
Financial_Impact
FINANCIAL IMPACT
The changes described in the Addendum will not increase the cost of the Project.
Next_Steps
NEXT STEPS
Staff will file the Notice of Determination with the Los Angeles County Registrar-Recorder/County Clerk for the Westside Purple Line Extension Project.
Attachments
ATTACHMENTS
Attachment A - Addendum to the Final Environmental Impact Report for the Westside Subway Extension Project
Attachment B - Notice of Determination
Prepared_by
Prepared by: Michael McKenna, Executive Officer, Project Management (213) 312-3132
David Mieger, Executive Officer, Countywide Planning and Programming (213) 922-3040
Manjeet Ranu, Senior Executive Officer, (213) 418-3157
Reviewed_By
Reviewed by: Therese McMillan, Chief Planning Officer (213) 922-7077
Richard Clarke, Chief Program Management Officer (213) 922-7557
