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DEFINITIONS AND ACRONYMSAbutment - A stone, concrete, brick, or timber structure supporting the end of a span.
Advisory Council on Historic Preservation (ACHP) - An independent federal agency that provides a forum for influencing federal policy, programs, and activities as they affect historic and archaeological resources in communities and on public lands nationwide.
Alluvial - Resulting from the operations of water, including floodplains, lakes, rivers, and fans at the foot of mountain slopes.
Anchorage - An assemblage of material designed to hold in correct position the anchor span of a cantilever bridge or the end of a suspension span cable.
Attainment area - An area that meets air quality standards.
Attenuation - The reduction of noise.
San Francisco Bay Regional Water Quality Control Board (RWQCB) - An agency with the California Environmental Protection Agency that is responsible for regulating pollutants to protect the water resources of the Bay Area.
Bay mud - Soft to stiff silty clay with some shell fragments that is found in the Bay. It is generally unsuitable for structure foundations.
Bedrock - Solid rock that underlies all soil, sand, clay, gravel, and loose material on the earth's surface.
Bent - A bridge support column founded on land.
Biological opinion - A document that is the product of formal consultation, stating the opinion of the USFWS on whether or not a federal action is likely to jeopardize the continued existence of listed species or result in the destruction or adverse modification of critical habitat.
Bracing - A system of tension or compression members that supports a truss or frame.
Cable - The part of a bridge that has the function of receiving the bridge floor loads and transmitting them to the towers and the anchorages.
Cable-stayed span - A span that involves steel cables that connect towers directly to support the bridge deck.
California Department of Fish and Game (CDFG) - The state agency that manages California's wildlife and plant resources.
California Department of Transportation (Caltrans) - Responsible for planning, designing, building, operating, and maintaining California's state highway system.
Candidate species - Any species of fish, wildlife, or plant which has been determined to be candidates for listing under Section 4 of the Endangered Species Act of 1973 (amended).
Cantilever span - A general term applying to a bridge having a superstructure of the cantilever type (supported at one end only).
Coastal Zone Management Act (CZMA) - The CZMA regulates development in coastal areas to protect the unique resources in such areas.
Cofferdam - A temporary water-tight enclosure built in the water and pumped dry to expose the bottom so that construction of piers can be undertaken.
Column - A supporting pillar.
Contaminant source - A facility that treats, stores, or disposes of hazardous waste, uses hazardous substances, or stores petroleum products on site.
Cultural resources - Archaeological and historic resources eligible for or listed on the National Register of Historic Places. Cultural resources include buildings, sites, districts, structures, or objects having historical, architectural, archaeological, cultural, or scientific importance.
Cumulative impact - The impact on the environment that results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions.
Day-Night Equivalent Sound Level (Ldn) - A 24-hour equivalent sound level with a 10 dB penalty assessed to noise events occurring at night (10:00 p.m. to 7:00 a.m.).
dBA - A sound level in decibels, measured with a sound level meter having metering characteristics and frequency weighting specified in American National Standard Specifications for sound level meters (ANSI S1.4-1971). It is common to refer to numerical units of an A-weighted sound level as "dBA."
Deck - The portion of a bridge that provides direct support for vehicular, bicycle, and/or pedestrian traffic.
Draft Environmental Impact Statement (DEIS) - A draft report that analyzes potential environmental impacts of a proposed project in compliance with NEPA.
Dredged Material Management Office (DMMO) - An interagency coordination group, consisting of the U.S. Army Corps of Engineers, the U.S. Environmental Protection Agency, the San Francisco Bay Conservation and Development Commission, the State Lands Commission, and the Regional Water Quality Control Board, that determines the suitability of in-Bay disposal for dredged materials.
Edge truss - Horizontal trusswork that is extended from the base of a lower deck to the bottom of an upper deck.
Endangered species - Any species of wildlife or plant which has been determined to be endangered under Section 4 of the Endangered Species Act of 1973 (amended). This definition is adopted from the USFWS, Section 7 regulations, 51 FR 19926.
Equivalent Sound Level (Leq) - A measure of sound energy over a period of time, or a sound level which, in a stated period of time, would contain the same acoustical energy as the time-varying sound during the same period.
Expansion joint - A joint designed to provide means for expansion and contraction movements produced by temperature changes, loadings, or other means.
4 (f) resources - Resources protected by Section 4(f) of the Department of Transportation Act. These include public park and recreation lands, wildlife and waterfowl refuges, and historic sites eligible or listed on the National Register.
Falsework - A temporary wooden or metal framework built to support a structure under construction until that structure is self-supporting.
Federal Aviation Administration (FAA) - The federal agency that issues and enforces regulations and standards related to the manufacture, operation, certification, and maintenance of aircraft.
Federal Highway Administration (FHWA) - The federal agency that coordinates highway transportation programs in cooperation with states and other partners. It provides federal financial assistance to the States to construct and improve the National Highway System, urban and rural roads, and bridges.
Federal Transit Administration (FTA) - The federal agency that provides financial and technical assistance to local transit systems. It also assists in the development of local and regional traffic reduction programs.
Fill - Earth used to create embankments or to raise low-lying areas in order to bring them to grade. Under the Clean Water Act (ACOE jurisdiction), fill is defined as material used for the primary purpose of replacing an aquatic area with dry land, or a change in the bottom elevation of a water body. Under the McAteer-Petris Act (BCDC jurisdiction), fill is defined as any solid, pile-supported, floating, cantilevered, or suspended material that is placed bayward of the Mean High Tide Line, or the +1.5-meter (5.0-foot) contour line where marshlands are present.
Final Environmental Impact Statement (FEIS) - A document that responds to comments received on the DEIS and provides updated information that has become available after publication of the DEIS.
Floodplain - The part of the ground surface inundated with water on a recurring basis, usually associated with the one percent recurrence interval (100-year) flow.
Footing - The enlarged, or spread-out, lower portion of a substructure, which distributes the structure load either to the earth or to supporting piles.
Foundation - The supporting material upon which the substructure portion of a bridge is placed.
Franciscan Formation - Regional bedrock that is approximately 90 to 160 million years old. It is composed of sandstone and shale and is generally highly weathered.
General Plan - A document that contains policies used to implement the goals of a community.
Geomorphic - Of the earth's surface configuration.
Girder - A horizontal beam used as a main support for a structure.
Grade - A slope or gradual incline.
Groundwater - Water beneath the earth's surface between saturated soil and rock that supplies wells and springs.
Haunched girder - An arched beam used between support piers.
High Occupancy Vehicle (HOV) - Vehicles occupied by two (sometimes three) or more persons such as carpools and buses.
High Occupancy Vehicle Lane (HOV Lane) - A system of exclusive lanes signed and striped for use by vehicles with multiple occupants (two or more or three or more persons). HOV lanes are designed on roadways to reduce traffic congestion, improve safety, reduce fuel consumption, and improve air quality.
Historic American Building Survey (HABS) - Founded by the National Park Service to document and archive significant historic architectural works.
Historic American Engineering Record (HAER) - Founded to document and archive significant engineering and industrial sites.
Inundation - The act of covering with water.
Isolator bearing - A bearing developed to protect structures against earthquake damage. Under seismic loading, the bearing becomes more flexible. This allows it to isolate the structure from the effects of earthquake motion.
Landscape unit - A geographically distinct portion of an area that has a particular visual character.
Lateral bracing - A horizontal bracing assemblage on a structure. Its function is to help the structure resist wind, lateral vibration, and traffic movement tending to produce lateral movement and deformation.
Lattice work - A structure made of lattices that is used to secure another structure in place.
Least Environmentally Damaging Practicable Alternative (LEDPA) - This designation is identified under the Federal Clean Water Act Section 404 (b)(1) alternatives evaluation process. The Section 404 (b)(1) process requires ACOE and EPA to make a determination of the LEDPA for any action involving discharge of dredge or fill material into waters of the U.S.
Level of Service (LOS) - The operating level of an intersection or roadway segment can be described using the term Level of Service. Level of Service is a qualitative description of operation based on delay and maneuverability. It can range from "A" representing free flow conditions to "F" representing gridlock.
Lifeline - A connection that provides for post-earthquake relief access linking major population centers, emergency relief routes, emergency supply and staging centers, and intermodal links to major distribution centers.
Liquefaction - The loss of strength that can occur in loose, saturated soil during or following seismic shaking. This condition can produce a number of ground effects, including lateral spreading, boils, ground lurching, and settlement of fill material.
Maintenance area - An area that had previously been designated a non-attainment area, but now meets applicable air quality standards.
Marine Mammal Protection Act - Provides for the protection and conservation of marine mammal species.
Maximum Credible Earthquake (MCE) - The largest earthquake reasonably capable of occurring based on current geological knowledge.
Metamorphic - Pertaining to an alteration in composition, texture, or structure of rock masses caused by great heat and/or pressure.
Metropolitan Transportation Commission (MTC) - The transportation planning, coordinating, and financing agency for the nine-county San Francisco Bay Area. It functions both as the region's metropolitan transportation planning agency (RTPA) and as the region's metropolitan planning organization (MPO)-state and federal designations, respectively.
Migratory Bird Treaty Act of 1918 - Reflects agreements involving the United States, Great Britain (for Canada), Mexico, Japan, and the former Soviet Union to protect migratory bird populations.
Mitigation - Measures taken to minimize adverse environmental impacts. Mitigation could reduce the magnitude and extent of an impact from a level of significance to a level of insignificance.
National Environmental Policy Act (NEPA) - The United States' basic national charter for protection of the environment. It establishes policy, sets goals, and provides means for carrying out the policy.
National Geodetic Vertical Datum (NGVD) - A fixed surface reference established by the U.S. Coast and Geodetic Survey in 1929 as the datum to which relief features and elevation data are referenced.
National Historic Preservation Act of 1966 - The primary federal law pertaining to protection of cultural resources, referred to as Section 106.
National Marine Fisheries Service (NMFS) - The part of the National Oceanic and Atmospheric Administration that oversees the Administration's programs which support the domestic and international conservation and management of living marine resources.
National Register eligible - Cultural resources eligible for inclusion on the National Register of Historic Places.
National Register of Historic Places - A federal listing of historic resources protected under the National Historic Preservation Act of 1966.
Navigation channel - An area of water used for marine vessel travel under bridges.
Non-attainment area - An area that does not meet air quality standards.
Noise Abatement Criteria - Noise level standards above which noise reducing actions should be considered.
Outfall - The place where a sewer, drain, or stream discharges into adjacent water.
Pier - A structure composed of stone, concrete, brick, steel or wood and built in shaft or block-like form to support the ends of the spans of a multi-span superstructure at an intermediate location between its abutments.
Pile - A rod or shaft-like linear member driven into the earth as a foundation or support for a structure.
Pile cap - The topmost portion of a pier. On rigid frame piers, the term applies to the beam across the column tops.
Portal - The clear unobstructed space of a through bridge forming the entrance to the structure.
Profile - refers to the rise in roadway elevation.
Record of Decision - A public document that explains the reasons for a project decision and summarizes any mitigation measures that will be incorporated in the project.
Right-of-way - Land, property, or interest therein, acquired for infrastructure such as a highway, railbed, pipeline, electric power lines, or telephone facilities. The land has been set aside as an easement or in fee, either by agreement or by condemnation.
Riparian - An aquatic or terrestrial ecosystem that is associated with bodies of water, such as streams, lakes, or wetlands, or is dependent upon the existence of perennial, intermittent, or ephemeral surface or subsurface water drainage. Riparian areas are usually characterized by dense vegetation and an abundance and diversity of wildlife.
Riprap - Brickbats, stones, blocks of concrete or other materials deposited upon shores to prevent erosion and scour by water flow.
Rock-wedge Failure - A movement or sliding of rock mass, possibly including overlying soil, along existing discontinuities such as fractures or joints within the rock fabric.
Safety Evaluation Event (SEE) - An earthquake that generates the largest motions expected to occur at a site within an established time interval. For the East Span Project, the time interval is 1,500 years.
San Francisco Bay Conservation and Development Commission (BCDC) - The state agency responsible for protecting and enhancing the San Francisco Bay. Two of its mandates are to prevent the unnecessary filling of the San Francisco Bay and to increase public access to and along the Bay shoreline. BCDC is also the federally designated state coastal management agency for the San Francisco Bay segment of the California coastal zone authorized under the federal Coastal Zone Management Act.
Sediment Sampling and Analysis - The process of evaluating the physical, chemical, and biological make-up of potential dredged sediment.
Self-anchored suspension bridge - A suspension bridge where cables are anchored in the bridge deck itself, eliminating the need for traditional anchorage structures.
Shoal - A place in a body of water where the water is particularly shallow.
Silt - A sedimentary material consisting of fine mineral particles in size between sand and clay.
Skyway span - A span that is supported from under the bridge deck by piers.
Special status species - Any species of fish, wildlife, or plant that is officially listed as rare, threatened, endangered, or candidate for rare, threatened, or endangered species listing under the state or federal Endangered Species Acts.
Spit - A narrow point of land extending into a body of water.
State Implementation Plan (SIP) - A plan for attaining national ambient air quality standards required by the Clean Air Act.
State Office of Historic Preservation - The state agency that assists private citizens, private institutions, local governments, and state and federal agencies in the identification, evaluation, protection, and enhancement of properties significant in California history and archaeology; also responsible for reviewing federal undertakings that affect cultural resources on or eligible for the National Register of Historic Places.
Stress - An applied force or system of forces that tends to strain or deform a body.
Substructure - The abutments, piers, or other constructions built to support the span or spans of a bridge. The superstructure is supported by the substructure; the substructure is placed on the foundations.
Superelevation - The transverse inclination of the roadway surface within a horizontal curve. The purpose of superelevation is to provide a means of resisting or overcoming the centrifugal forces of vehicles in transit.
Superstructure - The entire portion of the bridge structure that primarily receives and supports highway, railway or other traffic loads. It is supported by the substructure.
Surface runoff - Water that runs off streets and land and enters a body of water.
Suspension bridge - A span in which cables are draped from towers and connected to anchorages on either end of the bridge, and the bridge deck is supported by vertical connections to the cables.
Tectonic - Pertaining to structural deformations in the earth's surface.
Temporary structure - A structure that is used to support a permanent structure that is temporarily unable to support itself.
Tower - A pier or frame serving to support the cables of a bridge.
Traffic Management Plan - A plan to manage traffic during construction of projects to reduce congestion.
Trestle - A timber, reinforced concrete, or steel structure, usually consisting of many short spans, used to support a temporary or permanent bridge or used temporarily to construct a permanent bridge.
Truss - A jointed structure having an open built web construction so arranged that the frame is divided into a series of triangular figures.
Tsunamis - Seismically induced sea waves that are generated when large subsea earth or rock masses are displaced during earthquakes or very large landslides.
U.S. Army Corps of Engineers (ACOE) - Federal agency with jurisdiction over waters of the U.S.
U.S. Coast Guard (USCG) - Federal agency with jurisdiction over navigable waterways.
U.S. Environmental Protection Agency (EPA) - The federal agency responsible for maintaining environmental quality, including air quality, noise, and hazardous waste management.
U.S. Fish and Wildlife Service (USFWS) - The federal agency that administers the federal Endangered Species Act and is involved in protection of fish and wildlife habitat, including wetland areas.
Viaduct - A series of spans or arches used to carry a road or railroad over a wide valley or over other roads or railroads.
Visual dominance - The contrast between a project and its setting, described in terms of vegetation, landform, and structural changes.
Visual image type - An area that exhibits a fairly homogeneous visual quality. Types that are present in the SFOBB study area include recreational, industrial, institutional/military, historical, and open space.
Watershed - the point of high ground dividing two different drainage systems.
Waterway - The available width for the passage of water beneath a bridge.
Wetlands - According to regulations of the U.S. Army Corps of Engineers, wetlands are areas that are inundated or saturated by surface water or groundwater at a frequency and duration sufficient to support, under normal conditions, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, and similar areas and are subject to protection under Executive Order 11990 and Section 404 of the Clean Water Act.
AADT Average Annual Daily Traffic
AASHTO American Association of State Highway and Transportation Officials
AATC Advanced Automatic Train Control
ABAG Association of Bay Area Governments
AC Transit Alameda-Contra Costa Transit District
ACHP Advisory Council on Historic Preservation
ACOE U.S. Army Corps of Engineers
ADEIS Administrative Draft Environmental Impact Statement
ADT Average Daily Traffic
AHC Ad Hoc Committee on Seismic Ground Motions
APE Area of Potential Effect
ASR Archaeological Survey Report
BAAQMD Bay Area Air Quality Management District
BART Bay Area Rapid Transit District
BATA Bay Area Toll Authority
BCDC San Francisco Bay Conservation and Development Commission
BEQ Bachelor Enlisted Quarters
BMPs Best Management Practices
BPAC Bicycle/Pedestrian Advisory Committee
BRAC Base Realignment and Closure
CAA Federal Clean Air Act
Caltrans California Department of Transportation
CARB California Air Resources Board
CCAA California Clean Air Act
CCSF City and County of San Francisco
CDFG California Department of Fish and Game
CERCLA Comprehensive Environmental Response, Compensation and Liability Act
CEQ Council on Environmental Quality
CEQA California Environmental Quality Act
CESA California Endangered Species Act
CFR Code of Federal Regulations
CHP California Highway Patrol
CIH Certified Industrial Hygienist
CNDDB California Natural Diversity Database
CNPS California Native Plant Survey
CO Carbon Monoxide
CSHC California Streets and Highways Code
CWA Clean Water Act
CZMA Coastal Zone Management Act
CZMP Coastal Zone Management Plan
dBA A-weighted decibel
dBA Leq A-weighted decibel equivalent sound level
DEIR Draft Environmental Impact Report
DEIS Draft Environmental Impact Statement
DMMO Dredged Material Management Office
DMMP Dredged Material Management Plan
DTSC California Department of Toxic Substance Control
EA Environmental Assessment
EBMUD East Bay Municipal Utility District
EBRPD East Bay Regional Park District
EDAP MTC Bay Bridge Design Task Force Engineering and Design Advisory Panel
EFH Essential Fish Habitat
EIR Environmental Impact Report
EIS Environmental Impact Statement
EPA U.S. Environmental Protection Agency
ESA Environmentally Sensitive Areas
ESU Evolutionary Significant Unit
FAA Federal Aviation Administration
FCWA Federal Clean Water Act
FEIS Final Environmental Impact Statement
FHWA Federal Highway Administration
FISC Fleet and Industrial Supply Center
FSTIP Federal Statewide Transportation Improvement Program
FTA Federal Transit Administration
ha Hectare or hectares
HAER Historic American Engineering Record
HASR Historic Architecture Survey Report
HCM Highway Capacity Manual
HOV High Occupancy Vehicle
HPSR Historic Property Survey Report
HTL High Tide Line
HUD Department of Housing and Urban Development
HWCL Hazardous Waste Control Law
IR Installation Restoration
ISTEA Intermodal Surface Transportation Efficiency Act
JIT Joint Intermodal Terminal
km Kilometer or kilometers
kph Kilometers per hour
LEDPA Least Environmentally Damaging Practicable Alternative
L10 Noise level equaled or exceeded 10% of the time
Leq Equivalent Sound Level
Lmax Maximum Level
LPAB Landmarks Preservation Advisory Board
LRT Light Rail Transit
LTMS Long-Term Management Strategy
LUST Leaking Underground Storage Tank
m Meter or meters
MCE Maximum Credible Earthquake
mg/L Milligrams per Liter
mg/m3 Milligrams per Cubic Meter
MHTL Mean High Tide Line
MHW Mean High Water
mi Mile or Miles
MIS Major Investment Study
MLLW Mean Lower Low Water
MLW Mean Low Water
MOA Memorandum of Agreement
MOU Memorandum of Understanding
mph Miles per hour
MPO Metropolitan Planning Organization
MPRSA Marine Protection, Research, and Sanctuaries Act
MSL Mean Sea Level
MTC Metropolitan Transportation Commission
MTL Mean Tide Level
MUNI San Francisco Municipal Railway
NAAQS National Ambient Air Quality Standards
NAC Noise Abatement Criteria
NAHC Native American Heritage Commission
NEPA National Environmental Policy Act
NESHAPS National Emission Standards for Hazardous Air Pollutants
NGVD National Geodetic Vertical Datum
NHPA National Historic Preservation Act
NMFS National Marine Fisheries Service
NOD Notice of Determination
NPDES National Pollutant Discharge Elimination System
NPS National Park Service
NRHP National Register of Historic Places
NSTI Naval Station Treasure Island
NUAD Not Suitable for Unconfined Aquatic Disposal
O&M Operations and Maintenance
OARB Oakland Army Base
OBRA Oakland Army Base Reuse Authority
OES Office of Emergency Services
OSHA Occupational Safety and Health Administration
PAH Polyaromatic Hydrocarbon or Polynuclear Aromatic Hydrocarbon
PA/SI Preliminary Assessment/Site Investigation
PCB Polychlorinated Biphenyl
PDT Project Development Team
PG&E Pacific Gas and Electric Company
PIDP Pile Installation Demonstration Project
PM2.5 Particulate Matter with an Aerodynamic Diameter less than 2.5 Micrometers
PM10 Particulate Matter with an Aerodynamic Diameter less than Ten Micrometers
ppm Parts per Million
ROD Record of Decision
RCRA Resource Conservation and Recovery Act
RMP Regional Monitoring Program
RTP Regional Transportation Plan
RTPA Regional Transportation Planning Agency
RWQCB San Francisco Bay Regional Water Quality Control Board
SAP Sampling and Analysis Plan
SAR Sediment Sampling and Analysis Report
SARA Superfund Amendments and Reauthorization Act
SCPBRG Santa Cruz Predatory Bird Research Group
SEE Safety Evaluation Event
SF-11 San Francisco In-Bay Disposal Site at Alcatraz
SF DODS San Francisco Deep Ocean Disposal Site
SFEI San Francisco Estuary Institute
SFFD San Francisco Fire Department
SFOBB San Francisco-Oakland Bay Bridge
SFWD San Francisco Water Department
SHPO State Historic Preservation Officer
SIP State Implementation Plan
SUAD Suitable for Unconfined Aquatic Disposal
SVOC Semi-Volatile Organic Compound
SWPPP Storm Water Pollution Prevention Plan
TCE Temporary Construction Easement
TEA-21 Transportation Equity Act for the 21st Century
TI Treasure Island
TIDA Treasure Island Development Authority
TIP Transportation Improvement Program
TMP Traffic Management Plan
TPH Total Petroleum Hydrocarbons
TRPH Total Recoverable Petroleum Hydrocarbons
TSCA Toxic Substance Control Act
ug/m3 Micrograms per Cubic Meter
ug/L Micrograms per Liter
USC United States Code
USCG U.S. Coast Guard
USDA U.S. Department of Agriculture
USFWS U.S. Fish and Wildlife Service
USGS U.S. Geological Survey
UST Underground Storage Tank
VOC Volatile Organic Compound
VTS Vessel Traffic Service
WWTP Wastewater Treatment Plant
YBI Yerba Buena Island