Executive Summary and Full Report: Draft Environmental Impact Report/Supplemental Draft Environmental Impact Statement: BART and San Francisco Airport Extension
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Next Steps

How Do I Comment on the DEIR/SDEIS?

The public is invited to review the DEIR/SDEIS and to submit written comments to:

Molly Murphy Robert Hom, Program Director
Extension Planning - 1KB4 Federal Transit Administration,
San Francisco Bay Area Rapid Transit District Region IX
P.O. Box 12688 201 Mission Street
Oakland, CA 94604-2688 San Francisco, CA 94105

The purpose of the public review period is to solicit comments on the merits of the alternatives, the overall accuracy and completeness of the analyses, preferences for particular alternatives, and the sufficiency of the document in identifying and analyzing possible impacts of alternatives or mitigation measures to better avoid or reduce significant effects. Written comments may be submitted anytime during the 60-day public review period that begins with the release of the DEIR/SDEIS.

Additionally, the public is invited to participate at the upcoming public hearing that will be held to receive comments on the DEIR/SDEIS. The hearing will be announced in local newspapers and all individuals on the project mailing list will be notified. To get on the mailing list or request further project information, call the Project Hotline at (415) 398-2002.

Where Can Others Get Copies of the DEIR/SDEIS?

Copies of the DEIR/SDEIS have been distributed to each of the local jurisdictions (typically, the Planning Department), to public libraries along the project corridor, and to the BART and MTC libraries in Oakland. Copies can also be obtained by calling the Project Hotline.

What Will Happen at the Public Hearing?

As noted above, BART and SamTrans will hold a public hearing to describe the project alternatives and potential impacts, and to solicit comments from the public. These comments will be recorded by court reporters. The Boards will consider these comments during their deliberations on the selection of the Locally Preferred Alternative. BART, SamTrans, and their consultants will subsequently prepare written responses to be included in a FEIS/FEIR. The responses will address comments concerning environmental issues.

When Will a Decision Be Made to Build the BART-San Francisco Airport Extension?

Upon completion of the public hearing, BART and SamTrans will select a Locally Preferred Alternative. As noted earlier, the selection could be the existing proposed project as defined in May 1993, it could be one of the other alternatives evaluated, or it could be some hybrid based on a combination of different vertical alignments and station locations. BART and SamTrans will then direct preparation of a FEIS/FEIR to respond to comments on the DEIR/SDEIS. The FEIS/FEIR will also contain additional engineering and environmental analyses of the Locally Preferred Alternative. Only after review of the FEIS/FEIR by BART, SamTrans, and FTA and consideration of financial and engineering feasibility, local support, and cost-effectiveness will a decision be made on whether to extend BART to the SFIA.

 

Table S-7
Comparison of Key Impacts
Issue Proposed Project Locally Preferred Alternative I-380 least-Cost Design Option Alternative I No Build Alternative II TSM Alternative III Base Case Alternative IV
Airport Aerial East of Highway 101		 Alternative V
Minimum Length Subway to Millbrae		 Design Option V-A
Minimum Length Subway to Airport GTC		 Design Option V-B
Minimum Length Subway to San Bruno		 Alternative VI
Millbrae Ave. via Airport International Terminal
  
Transit Ridership   
  • Increase in Daily Regional Ridership (passengers) compared to No Build in 1998.
  • 35,800
  • Same as proposed project
  • N/A
  • 2,100
  • 36,100
  • 36,100
  • 36,500
  • 35,700
  • 35,900
  • 38,400
  
  • Daily BART Patronage in San Mateo County in 1998 (entrances and exits)
  • 80,700
  • Same as proposed project
  • 45,00
  • 41,900
  • 81,000
  • 82,800
  • 84,100
  • 81,100
  • 80,900
  • 88,300
  
Traffic
  • Freeway (compared to 1993 No Build conditions).
  • Reduces regional congestion.
  • Reduces Highway 101 level of service between SFIA and Millbrae and between Millbrae and Broadway and between Poplar and Third to unacceptable levels in 1998 and 2010.
  • Reduces highway 101 levels of service between Broadway and Poplar to unacceptable levels in 2010.
  • Exacerbates already unacceptable levels of service on Highway 101 between Broadway and Poplar Avenue in 1998.
  • Reduces Highway 101 weaving section between SFIA and Millbrae Avenue in 1998 and 2010.
  • Reduces Highway 101 waving section between San Bruno Avenue and SFIA to unacceptable levels in 1998 and 2010.
  • Same as proposed project
  • Reduces Highway 101 level of service between Poplar and Third Avenues to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 level of service between SFIA and Millbrae and between Broadway and Poplar Avenue to unacceptable levels in 2010.
  • Reduces Highway 101 weaving section between San Bruno Avenue and SFIA and between SFIA and Millbrae Avenue to unacceptable levels in 1998 and 2010.
  • Reduces regional congestion.
  • Reduces Highway 101 level of service between Millbrae and Broadway and between Poplar and third Avenue to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 waving section between SFIA and Millbrae Avenue to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 weaving section between San Bruno and SFIA to unacceptable levels in 2010.
  • Reduces regional congestion.
  • Reduces Highway 101 level of service between SFIA and Millbrae and between Millbrae and Broadway and between Poplar and Third to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 level of Service between Broadway and Poplar to unacceptable levels in 2010.
  • Exacerbates already unacceptable level of service on Highway 101 between Broadway and Poplar Avenue in 1998.
  • Reduces Highway 101 weaving section between San Bruno and SFIA to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 weaving section between SFIA and Millbrae Avenue in 1998 and 2010.
  • Same as Alternative III except
  • Improves Highway 101 weaving operations between San Bruno and SFIA in 1998.
  • Reduces Highway weaving section between San Bruno and SFIA to unacceptable levels in 2010.
  • Reduces regional congestion.
  • Reduces Highway 101 level of service between SFIA and Millbrae and between Millbrae and Broadway and between Broadway and Poplar  and between Poplar and Third Avenue and to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 weaving section between SFIA and Millbrae Avenue in 1998 and 2010.
  • Improves Highway 101 weaving operations between San Bruno and SFIA in 1998.
  • Reduces Highway weaving section between San Bruno and SFIA to unacceptable levels in 2010.
  • Reduces regional congestion
  • Reduces Highway 101 level of service between SFIA and Millbrae and between Millbrae and Broadway to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 level of service between Broadway and Poplar and between Poplar and Third to unacceptable levels in 2010.
  • Reduces Highway 101 weaving section between San Bruno Avenue and SFIA in 1998 and 2010.
  • Exacerbates already unacceptable levels of service on Highway 101 between Broadway and Poplar and between Poplar and Third Avenue in 1998.
  • Reduces Highway 101 weaving section between SFIA and Millbrae Avenue in 1998 and 2010.
  • Same as Design Option V-A
  • Reduces regional congestion.
  • Reduces Highway 101 level of service between Millbrae and Broadway and between Broadway and Poplar and between Polar and Third Avenue to unacceptable levels in 1998 and 2010.
  • Reduces Highway 101 level of service between SFIA and Millbrae to unacceptable levels in 2010.
  • Reduces Highway 101 weaving operations between SFIA and Millbrae in 2010.
  
  • Local Intersections (Compared to 1993 No Build Conditions)
  • Significant deterioration in LOS at Hickey extension/station exit in PM, El Camino Real/Sneath in PM, and Chestnut/Grand in PM.
  • Same as proposed project.
  • Significant deterioration in LOS at Chestnut/Grand, El Camino Real/Westborough, El Camino Real/Sneath, and California/Broadway.
  • Exacerbates already unacceptable LOS at Junipero Serra/Westborough, El Camino Real/Noor, and 2nd/San Bruno
  • Generally same or improved LOS at local intersections.
  • Significant deterioration of LOS at El Camino Real/Sneath.
  • Exacerbates already unacceptable levels of service at Junipero Serra/Westborough.
  • Significant deterioration in LOS at the Hickey extension/station exit in PM.  Chestnut/Grand in PM and San Mateo/Huntington and San Anselmo/Center in the PM.
  • If Tanforan Station option were selected, reduced LOS at El Camino Real/Sneath.
  • Same as Alternative IV plus
  • For the Downtown San Bruno Station option, impacts would be the same as those identified for the I-380/San Bruno Station except that San Mateo/Angus would also be significantly affected.
  • Significant deterioration in LOS at San Mateo/Huntington in PM, San Mateo/Lumber Yard Kiss-and-Ride exit in PM, the Hickey extension/station exit and Chestnut/Grand, in PM.
  • Same as Design Option V-A.
  • Significant deterioration in LOS at Hickey extension/station exit and Chestnut/Grand in PM; El Camino Real/Sneath, Huntington/Tanforan Driveway North in PM, and El Camino Real/Millbrae in AM.
  • Parking in 2010
  • Reduction in parking demand of Daly City and Colma Stations.
  • Demand exceeds design at Daly City and Tanforan Stations.
  • Spillover parking into neighborhoods at Hickey and into Tanforan Shopping Center.
  • SFIA air passengers may park at the Airport Intermodal Station to access ALRS.
  • Same as proposed project.
  • Demand exceeds design at Daly City and Colma Stations.
  • Same as No Build Alternative.
  • Reduction in parking demand at Daly City and Colma Stations.
  • Demand exceeds design at Daly City, Chestnut, and Tanforan Stations.
  • Spillover parking into neighborhoods at Chestnut Station, the Airport Intermodal Station, and into Tanforan Shopping Center.
  • SFIA air passengers may park at the Airport Intermodal Station to access ALRS.
  • Reduction in parking demand at Daly City and Colma Stations.
  • Demand exceeds design at Daly City Station.
  • Spillover parking into neighborhoods at Hickey, I-380/San Bruno, and Millbrae Intermodal Stations, and into Tanforan Shopping Center.
  • SFIA passengers may park at the Millbrae Intermodal Station to access ALRS.
  • Reduction in parking demand at Daly City and Colma Stations.
  • Demand exceeds design at Daly City and Millbrae Intermodal Stations.
  • Spillover parking same as Alternative IV.
  • SFIA air passengers may park at the Millbrae Intermodal Station to access ALRS.
  • Reduction in parking demand at Daly City and Colma Stations.
  • Demand exceeds design at Daly City Station.
  • Spillover parking into neighborhoods at Hickey, I-380/San Bruno or Downtown San Bruno stations.
  • SFIA air passengers may park at I-380/San Bruno or Downtown San Bruno Stations to access ALRS.
  • Same as Design Option V-A.
  • Reduction in parking demand at Daly City and Colma Stations.
  • Same as Design Option V-A, buy additional spillover parking at Tanforan and Millbrae Avenue Stations.
  
Land Use   
  • General Plan Consistency
  • Generally consistent with San Bruno Plan.
  • Conflicts with San Bruno Plan
  • No effect.
  • No effect
  • Conflicts with Colma, South San Francisco, and San Bruno Plans.
  • Conflicts with San Bruno and Millbrae Plans
  • Conflicts with San Bruno and Millbrae Plans
  • Conflicts with San Bruno Plan.
  • Conflicts with San Bruno Plan
  • Generally consistent with San Bruno Plan but conflicts with Millbrae Plan.
  
  • Displacement
  • 120 residents; up to 130 employees.
  • Same as proposed project.
  • No displacement.
  • No or little displacement.
  • No residential displacement; up to 40 employees.
  • Up to 560 residents; up to 490 employees.
  • Up to 600 residents; up to 605 employees.
  • Up to 650 residents; up to 565 employees.
  • Same as design Option V-A.
  • Up to 525 residents; up to 60 employees.
  
  • Community Cohesion/Local Economic Activity in Station Vicinity
  • Minimally affects real estate or economic development except
  • At Hickey where it supports local development objectives.
  • Displacement at Hickey Station disrupts local patterns of shopping circulation, and neighborhood activities.
  • Displacement of Tanforan Shopping Center overflow parking for Tanforan Station may affect economic development.
  • Same as proposed project.
  • No effect.
  • Minimally affects real estate at the CalTrain/Airport Light Rail Station.
  • Conflicts with residential development objectives in South San Francisco.
  • Displacement of Tanforan Shopping Center overflow parking for Tanforan Station may affect economic development.
  • Chestnut Station displaces 18-stall golf driving range and bar/cafe.
  • Displacement at Hickey Station disrupts local social patterns of shopping, circulation, and neighborhood activities.
  • Displacement of Tanforan Shopping Center overflow parking for Tanforan Station may affect economic development.
  • Loss of municipal and school tax revenues in San Bruno with I-380 Station option.
  • Economic / isolation impacts in Millbrae.
  • Loss of the Millbrae Nursery School and Marino Vista Park.
  • Displacement at Hickey Station disrupts local social patterns of shopping, circulation, and neighborhood activities.
  • Displacement of Tanforan Shopping Center overflow parking for Tanforan Station may affect economic development.
  • Loss of municipal and school tax revenues in San Bruno, with either I-380 or Downtown San Bruno Station.
  • Disrupts the San Bruno Central Business District.
  • I-380/San Bruno Station affects Belle Air and San Bruno Park neighborhoods.
  • Loss of Posy Park with Downtown San Bruno Station.
  • Economic/isolation effects in Millbrae.
  • Loss of the Millbrae Nursery School and Marino Vista Park.
  • Same as Alternative V except
  • Impact in San Bruno would be greater due to larger station; ALRS would further fragment Belle Air neighborhood plus
  • There would be no impacts at the Tanforan or Millbrae Intermodal Stations.
  • Same as Design Option V-A.
  • Displacement at Hickey Station disrupts local social patterns of shopping, circulation, and neighborhood activities.
  • Loss of municipal and school tax revenues in San Bruno and Millbrae;
  • Requires relocation of Millbrae Gardens.
  
  • Community Cohesion/Social Considerations (Not in Station Vicinity but along Alignment)
  • Fragments Fifth Addition.
  • Impacts Belle Air neighborhood.
  • Reduces supply of low-income housing in San Bruno and San Mateo County.
  • Fragments Fifth Addition more than proposed project because of aerial configuration.
  • Impacts Belle Air Elementary School and 7th and Walnut Park.
  • No neighborhood impacts.
  • No BART-related neighborhood impacts.
  • Increased activity along CalTrain right-of-way would impact South San Francisco, San Bruno, and Millbrae, and along the Hickey Boulevard extension in South San Francisco.
  • Introduces land use incompatibility with cemeteries in Colma.
  • Introduces physical barrier in South San Francisco and San Bruno.
  • Displaces approximately 400 spaces of municipal, private, and CalTrain parking.
  • Introduces physical barrier in Belle Air neighborhood.
  • Impacts Belle Air neighborhood in San Bruno and Marino Vista and North Millbrae neighborhoods in Millbrae.
  • Reduces supply of low-cost housing in San Bruno and San Mateo County.
  • Impacts Belle Air neighborhood in San Bruno and Marino Vista and North Millbrae neighborhoods in Millbrae.
  • Reduces supply of low-cost housing in San Bruno and San Mateo County.
  • Same as Alternative V.
  • Same as Alternative V.
  • Same as Alternative V.
  
  • Regional Economic Activity
  • Creates 675 to 1,125 direct\indirect jobs.
  • Same as proposed project
  • Creates few jobs.
  • Creates fewer jobs than proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
 
Visual Quality   
  • Built Environment
  • ALRS and Highway 101 connections introduce scale incompatibilities in Millbrae.
  • Same as proposed project
    plus
  • Scale incompatibilities would occur in Fifth Addition neighborhood in San Bruno.
  • No Effect.
  • Same as proposed project.
  • Same as proposed project
    plus
  • Aerial BART alignment introduces scale incompatibilities in San Bruno.
  • Same as proposed project
    plus
  • Aerial BART alignment and station options introduce scale incompatibilities with homes on east side of 3rd Avenue in San Bruno.
  • Same as Alternative IV
    plus
  • BART parking structure introduces scale incompatibilities with homes on east side of 3rd Avenue in San Bruno.
  • Same as Alternative V except
  • No effects in Millbrae.
  • BART parking structure introduces scale incompatibilities with homes on east side of 3rd Avenue in San Bruno.
  • Same as Design Option V-A.
  • BART facilities introduce scale incompatibilities in Millbrae.
  • Tanforan Station would introduce scale incompatibilities in San Bruno.
  
  • Scenic Resources and Significant Views
  • Temporary removal of mature trees in Colma and South San Francisco
  • Storage tracks and car wash affect views and scenic resources in Millbrae.
  • ALRS and Highway 101 ramps obstruct views of San Bruno Mountain and diminish appeal of SFIA open space area  west of Highway 101.
  • Same as proposed project.
  • No effect.
  • ALRS and Highway 101 ramps obstruct view of San Bruno Mountain from Millbrae and diminish appeal of SFIA open space area west of Highway 101.
  • Same as proposed project
    except
  • Permanent removal of trees in Colma cemeteries.
  • Same as proposed project plus
  • Aerial configuration and Millbrae Intermodal significantly affects view of San Bruno Mountain.
  • No effect from storage tracks or car wash.
  • Same as proposed project but greater effect on views of San Bruno Mountain because of Millbrae Intermodal Station.
  • No effects from storage tracks or car wash.
  • Same as proposed project except
  • No effects on Millbrae.
  • Same as Design Option V-A.
  • Temporary removal of mature trees within Colma and South San Francisco.
  
  • Sensitive Receptors
  • Daly City Shop/Yard sound wall creates perception of encroachment for Meadowbrook Trailer park residents.
  • Tanforan Station facilities and alignment may create a sense of encroachment for San Bruno Residents.
  • Same as proposed project plus
  • I-380 aerial segment creates encroachment for homes in San Bruno's Fifth Addition neighborhood.
  • No effect.
  • No effect.
  • Same as proposed project
    plus
  • Retained cut effects cemeteries in Colma and residents in South San Francisco.
  • The Chestnut Station parking structure would introduce light and glare into South San Francisco.
  • Ancillary facilities, a retaining wall, and fencing create a sense of encroachment in South San Francisco.
  • Same as proposed project plus
  • Encroachment effects by San Bruno Station options and Millbrae Intermodal Station.
  • The I-380/San Bruno Station would introduce light and glare in San Bruno.
  • BART storage tailtrack would extend to within 60 feet of sensitive receptors in Millbrae.
  • Same as Alternative IV
    except
  • Light and glare effects at Downtown San Bruno Station instead of I-380 Station.
  • Same as Alternative V
    except
  • No effects on Millbrae.
  • Same as Design Option V-A.
  • Same as proposed project
    except
  • Light and glare effects in Bayside Manor neighborhood in Millbrae.
  
  • Streetscape
  • Hickey Station potentially enhances streetscape in South San Francisco.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Alters streetscape in San Bruno in vicinity of aerial segment and station.
  • Same as proposed project
    plus
  • Same as the Base Case Alternative.
  • Same as proposed project
    plus
  • Alters streetscape in San Bruno with I-380/San Bruno and Downtown San Bruno Station options.
  • Same as Alternative V
  • Same as Design Option V.
  • Same as proposed project
    plus
  • Alters streetscape in San Bruno at Tanforan Station.
  
Cultural Resources
  • Direct Physical Disturbance
  • potential direct effects to arched, cut-stone bridge in South San Francisco.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
    plus
  • Relocation of the Millbrae Train Station, a structure on the National Register of Historic Places.
  
  • Diminution of Historic Setting.
  • Diminution of setting in cemeteries in Colma.
  • Diminution of setting at Salem Memorial Park Office in Colma.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
    plus
  • Indirect effects on cemetery properties the Salem Memorial Park office, and the American Legion Post.
  • Same as proposed project.
  • Same as proposed project
    plus
  • Indirect effects to potentially historic downtown San Bruno properties.
  • Same as Alternative V
  • Same as Alternative V
  • Same as proposed project.
  
Community Services
  
  • Increases demand for local emergency response.
  • Minimal increase in water demand and wastewater treatment requirements.
  • Same as proposed project.
  • Emergency response vehicles would still be delayed by train passbys in San Bruno and Millbrae.
  • Negligible change in service demands.
  • Same as proposed project.
  • Same as proposed project with slightly greater demand due to one additional station.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
Geology    
  • Seismic Effects
  • Exposes BART facilities to potentially strong, seismically-induced groundshaking and lateral pressures.
  • Potential for seismically-induced strain on I-380 tunnel lining.
  • Same as proposed project excluding seismic strain.
  • No effect.
  • Exposes roadway and transit improvements to potentially strong, seismically-induced groundshaking.
  • Same as proposed project excluding seismic strain on tunnel.
  • Exposes BART facilities to potentially strong, seismically-induced groundshaking and lateral pressures
    plus
  • Potential for seismically-induced strain on tunnel under Highway 101.
  • Potentially strong seismically-induced groundshaking on facilities proposed on SFIA property cast of Highway 101.
  • Same as proposed project excluding seismic strain on tunnel.
  • Same as Alternative IV.
  • Same as proposed project.
  • Same as Alternative IV.
    plus
  • Potential for seismically-induced strain with Tunnel Construction Option.
  
  • Liquefaction/ Bay Mud Effects
  • Exposes BART facilities, ALRS, and highway on off-ramps overlying San Francisco Bay Mud to seismically-induced, localized liquefaction and settlement.
  • Same as proposed project.
  • No effect.
  • Exposes roadway and transit improvements to seismically-induced, localized liquefaction and settlement.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project excluding effects on highway on/off ramps.
  • Same as Design Option V-A.
  • Same as Design Option V-A.
  
  • Hydrostatic and Settlement Effects
  • Exposes BART facilities below groundwater level to seismically-induced upward force.
  • Facilities involving spread footings would be susceptible to long-term ground settlement.
  • Same as proposed project.
  • No effect.
  • Spread footings susceptible to long-term settlement.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
  • Corrosive Subsurface Soils
  • Potentially exposes underground structures to corrosive subsurface soils.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
Biological Resources   
  • Total Wetland Loss (approximate acreage of wetlands and creek channels)
  • 2.42
  • 2.62
  • No effect.
  • 1.09
  • 1.82
  • 1.80
  • 1.26
  • 1.27 to 1.28
  • 1.12
  • 0.87
  
  • Loss of Wetland Habitats inhabited by the San Francisco Garter Snake, California Red-legged frog, and the San Francisco Forktail Damselfly.
  • 1.52 acres of wetland habitats and obstruction of movement corridors within sensitive wildlife species habitat.
  • 1.54 acres of wetland habitats.
  • Results in continued decline of San Francisco Garter Snake and Red-legged frog habitat.
  • 0.93 acres of wetland habitats.
  • 1.16 acres of wetland habitats.
  • 0.91 acres of wetland habitats.
  • 0.37 acres of wetland habitats.
  • 0.40 to 0.41 acres of wetland habitats.
  • 0.25 acres of wetland habitats.
  • No displacement of wetlands habitats, resulting in the least impact of all alternatives.
  
  • Reduction in aquatic habitat value.
  • Additional drainage outfalls into existing waterways could convey runoff and pollutants into aquatic habitats.
  • Same as proposed project.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
Hydrology and Water Quality   
  • Flood Hazard
  • Encroaches into the 100-year floodplain in Colma, South San Francisco, and on west of Bayshore parcel, and may increase risk of flooding in adjacent areas.
  • Reconstruction of a stretch of Colma Creek in South San Francisco would improve the discharge of stormwaters.
  • Same as proposed project
    except
  • Retained cut segment in west of Bayshore parcel would disrupt drainage and increase flood hazards in this area.
  • No flood control improvements to Colma Creek would be made.
  • Same as proposed project
    except
  • No encroachment in Colma and San Bruno.
  • Placement of a station in the 100-year floodplain of Colma Creek at Chestnut Boulevard, and encroaches into the floodplain on west of Bayshore parcel.
  • Similar to proposed project but I-380/San Bruno Station option would encroach upon flood prone area in San Bruno.
  • Similar to Alternative IV, but less encroachment on the west of Bayshore parcel.
  • Similar to Alternative V
    except
  • Less encroachment on the west of Bayshore parcel.
  • Same as Design Option V-A
    except
  • No encroachment on west of Bayshore parcel.
  • Similar to Alternative V-A (subway)
    except
  • No encroachment on San Bruno Flood prone areas.
  
  • Soil Erosion
  • Results in significant erosion at the outlets of new and modified drainageways.
  • Same as proposed project.
  • No effect.
  • Results in less erosion than the proposed project; avoids Cupid Row Canal.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Results in less erosion than the proposed project because it avoids San Felipe-South Lomita Canal and existing culverts would be unaffected.
  
  • Water Quality
  • Results in increased runoff volumes (50 cfs) and greater pollutant loadings.
  • Same as proposed project.
  • No effect.
  • Results in less runoff volumes (32 cfs) and pollutant loading than the proposed project.
  • Same as proposed project.
  • Results in less runoff volumes (34-39 cfs) and pollutant loading than the proposed project due to less ground disturbance.
  • Results in less runoff volumes (33-44 cfs) and pollutant loading than the proposed project because it proposes one less station.
  • Results in less runoff volumes (18-23 cfs) and pollutant loading than the proposed project because it proposes one less station.
  • Same as Design Option V-A.
  • Results in potentially the least runoff volume (18 cfs) of all BART build alternatives because of minimal increases in impermeable surfaces.
  
  • Groundwater
  • Displaces one cemetery well in Colma.
  • Potentially contaminates underlying aquifer.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
Noise (maximum estimate of sensitive receptors)
  • Groundborne Noise
  • 121
  • 77
  • No effect
  • Not Applicable
  • Not Applicable
  • 77
  • 77
  • 103
  • 99
  • 113
  • Airborne Noise
  • 119
  • 216
  • No effect
  • 118
  • 312
  • 255
  • 228
  • 124
  • 101
  • 84
  • Vibration
  • 162
  • 156
  • No effect
  • Not Applicable
  • 136
  • 205
  • 180
  • 195
  • 196
  • 199
  • Site-Specific Unavoidable Impacts
  • None
  • None
  • None
  • None
  • None
  • None
  • None
  • None
  • None
  • Seven to eight homes in Millbrae would experience groundborne noise levels in excess of appropriate criteria.
  
Air Quality
  • Reductions in emissions from 1993 No Build by 1998 (000 tons/yr):
    Carbon Monoxide
    Nitrogen Oxides
    Reactive Organic Gases
    PM
         10
  • 318.9
  • 13.8
  • 20.6
  • 1.5
  • Similar to proposed project.
  • Worsens regional air quality compared to all BART build alternatives.
  • Similar to proposed project.
  • Similar to proposed project.
  • Similar to proposed project.
  • Similar to proposed project.
  • Similar to proposed project.
  • Similar to proposed project.
  • Similar to proposed project.
  
  • Highest Modeled 8-Hr. CO Concentration in 1998
  • 7.0
  • 7.0
  • 7.5
  • 8.4
  • 6.3
  • 7.3
  • 7.3
  • Similar to Alternative V.
  • 7.1
  • 6.5
  
  • Conformity Assessment
  • In conformance with the MTC resolution and Clean Air Act.
  • Same as proposed project.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
Public Health and Safety   
  • Exposure to Hazardous Materials
  • Introduces minimal volumes of hazardous materials for maintenance of facilities and equipment.
  • Low likelihood of exposure to known nearby contaminated sites.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  
  • Exposure to Electromagnetic Fields (EMF)
  • Minimal long-term exposure because of distance to and shielding of EMF sources from sensitive receptors.
  • Same as proposed project.
  • No effect.
  • No effect.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
  • Same as proposed project.
Energy
  • Regional Consumption (in billions of Btus/day)
  • 835.58
  • 835.58
  • 838.22
  • 834.47
  • 835.57
  • 835.61
  • 835.60
  • 835.59
  • 835.55
  • 835.65
  
  • BART Electrical Requirements (in millions of Btus/day)
  • 300.03
  • 295.37
  • Not Applicable
  • Not Applicable
  • 290.25
  • 333.91
  • 322.85
  • 307.0-307.58
  • 267.89
  • 371.29
  
Section 4(f) Evaluation (Loss of parklands)
  
  • Herman Tot Lot and 7th & Walnut Parks in San Bruno.
  • 7th & Walnut Park in San Bruno
  • No effect.
  • No effect.
  • Posy Park in San Bruno.
  • Marino Vista Park in Millbrae.
  • Posy Park in San Bruno and Marino Vista Park in Millbrae.
  • Posy Park in San Bruno.
  • Posy Park in San Bruno.
  • No effect.
  
Note: Bold and underline impacts indicate significant and unavoidable impacts.

Table S-8 Summary of Mitigation Measures
 

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