SECTION 4.0

ENVIRONMENTAL SETTING, IMPACTS, AND MITIGATION

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PROPOSED PROJECT

4.4    Water Resources and quality

The waters within San Francisco Bay provide critical sheltered water habitat for a wide variety of marine and aquatic species. These waters are important both ecologically and to commercial and recreational interests such as fisheries and water contact recreation. Bay resources are affected by commercial, transit, and recreational activities in the Bay because dredge and fill operations, fuel spills, and pollutants can adversely affect water quality.

This section presents the existing hydrology, water quality, and sediment quality in the Bay along with current water quality concerns. These concerns potentially relate to the proposed Project due to Hydroplow (or other equivalent cable-burial technology whose sediment disturbances are similar to those of the Hydroplow) activities. These potential concerns relate to: burying the cable in the bottom of the Bay, dredging along a small portion of the cable route, potentially polluted stormwater runoff from onshore construction of converter stations, temporary use of laydown areas, and construction of onshore cable routes and access roads.

4.4.1    Environmental Setting

San Francisco Bay is California's largest estuarine system, and its configuration and the surrounding landscape have been shaped by a combination of tectonic activity, recent sea level changes, and human activities. Since the formation of the Sacramento-San Joaquin drainage outlet through the Bay approximately 400,000 years ago, the environment of deposition has fluctuated between estuarine (periods of high sea level) and alluvial (periods of low sea level).

The present Bay estuary formed less than 10,000 years ago as the global climate warmed and sea levels rose. Seawater re-entered the Bay approximately 10,000 years ago and by about 4,000 years ago had reached its present level. With the establishment of true estuarine conditions, sedimentation in the Bay changed from alluvial sands and silts to dark-colored estuarine clays and silts, commonly called Bay Mud. Deposition of sandier sediment was confined to channels.

Since about 1850, human activities have made enormous modifications to the Bay, causing changes in the patterns of circulation and sedimentation. Between 1856 and about 1900, hydraulic mining in the Sierra foothills deposited several feet of sediment throughout the Bay. Starting in the 1800s, the construction of levees and dikes altered the patterns of drainage and annual flooding in the Sacramento River Delta. Also, the placement of fill at numerous localities around the Bay margins has dramatically altered the shoreline profile.

4.4.1.1    San Francisco Bay Estuary Hydrodynamics

San Francisco Bay and the San Joaquin-Sacramento River Delta form the largest estuary on the west coast of the United States. Shown on Figure 4.4-1, it encompasses roughly 1,600 square miles, drains more than 40 percent of the state, and provides drinking water to approximately two-thirds of California (SFEP, 1999). Here, fresh water from the rivers and numerous smaller tributaries flows out through the Bay to the Pacific Ocean. The San Francisco Bay Estuary (Estuary) is composed of three distinct hydrographic regimes: the South Bay, which extends from the Bay Bridge to the southern terminus of the Bay in San Jose, and the Central and North bays, which connect the delta and the Pacific Ocean.

The North Bay consists of several small embayments, the two largest being San Pablo Bay and Suisun Bay. The embayments are connected to each other and the ocean by deep, narrow channels ranging from 42 feet deep in San Pablo Bay to over 360 feet deep at the Golden Gate. San Pablo Bay is characterized by a deep channel surrounded by broad shoals. San Pablo Bay is connected to Suisun Bay by the narrow Carquinez Strait. Suisun Bay is a shallow basin consisting of braided channels and shallow shoals. The Central Bay has a highly complex bathymetry. East of the Golden Gate, the depth is approximately 300 feet, while extensive intertidal mudflats are present at the eastern edge of the Central Bay.

Freshwater inflows, tidal flows, and their interactions largely determine variations in the hydrology of the Estuary. Hydrology has profound effects on all species that live in the Estuary because it determines the salinity in different portions of the Estuary, and controls the circulation of water through the channels and bays.

Approximately 90 percent of the freshwater inflow to the Bay comes from the delta (Cheng et al., 1993) and flows through the northern portion of the Bay, resulting in a partially to well-mixed Estuary (Walters et al., 1985; Uncles and Peterson, 1995). The North Bay is hydrologically distinct from the Central and South Bays. The degree of mixing depends on seasonally varying river inflow. The timing and magnitude of the highly seasonal river inflow modulates permanent estuarine circulation, which is largely maintained by salinity-controlled density differences between river and ocean waters.

Currents in San Francisco Bay are dominated by tidal action. Tides in the Bay Area are classified as mixed semidiurnal, with two flood tides and two ebb tides of unequal range occurring over a 24.8-hour period. Mean tidal range at the Potrero power plant is 4.6 feet. Mean tidal range in Pittsburg is 3.0 feet. Currents measured at the National Oceanic and Atmospheric Administration (NOAA) station at Potrero Point range from 0 knots (kt) at slack tide to 2.3 kt at average maximum ebb tide and 2.5 kt at average maximum flood tide. Flood tides flow at 160° and ebb at 320° relative to north.

4.4.1.2    San Francisco Bay Water Quality

The overall goals of water quality regulation according to the Water Quality Control Plan for San Francisco Bay Basin (Basin Plan) (RWQCB, 2005) are to protect and maintain thriving aquatic ecosystems and the resources those systems provide to society, and to accomplish these goals in an economically and socially sound manner.

Since 1993, the San Francisco Estuary Institute (SFEI) has administered a Regional Monitoring Program (RMP) for the Regional Water Quality Control Board (RWQCB) and major Bay dischargers. Most dischargers to the Bay are required to participate in the RMP as a condition of their discharge permit. SFEI conducts monitoring from the Delta to the South Bay. The Estuary is divided into five regions, and eight random locations are sampled within each region each year for sediment quality (SFEI, 2005a). Four or more random locations within each region are sampled for water quality. In addition, a few historical fixed sites are sampled annually for long-term trend analysis.

The RMP seeks to characterize contaminant concentrations in San Francisco Estuary water, sediment, fish, and shellfish. The ultimate goal is to determine how contaminant concentrations in the Estuary are changing in response to pollution prevention and reduction measures, and to provide feedback to water quality management agencies. The five key objectives are:

• To describe patterns and trends in contaminant concentration and distribution

• To describe general sources and loadings of contamination to the Estuary

• To measure contaminant effect on selected parts of the Estuary ecosystem

• To compare monitoring information to relevant water quality objectives and other guidelines

• To synthesize and distribute information from a range of sources to present a more complete picture of the sources, distribution, fates, and effects of contaminants in the Estuary ecosystem

Data collected for the RMP indicate contamination areas in the Estuary. The primary known contamination problems include:

• The top water quality concerns in the Estuary are polychlorinated biphenyls (PCBs) and mercury

• Measured values of contaminants in the Estuary exceed relevant water, sediment, and tissue quality guidelines

• The South Bay most frequently exceeds the guidelines

• The northern and southern segments exceed the guidelines more frequently than the Central Bay

• Estuary waters do not tend to be toxic and there has been a decrease in the incidences of aquatic toxicity observed in the tributaries during storm events between 1997 and 2001

A summary of water quality data from the 2003 RMP Annual Monitoring Results Report (SFEI, 2005b) is presented in Table 4.4-1.

TABLE 4.4-1
SAN FRANCISCO BAY WATER QUALITY

¹   Source: RWQCB, 2005. Basin Plan.
²   Water quality objectives for copper were promulgated by the California Toxics Rule (CTR) and may be updated by EPA without amending the Basin Plan. Note: at the time of writing of the Basin Plan, the values are 3.1 µg/l (4-day average) and 4.8 µg/l (1-hr. average).
³   Selenium criteria were promulgated for all San Francisco Bay/Delta waters in the National Toxics Rule (NTR). The NTR criteria specifically apply to San Francisco Bay upstream to and including Suisun Bay and Sacramento-San Joaquin Delta. Note: at the time of writing of the Basin Plan, the values are 5.0 µg/l (4-day average) and 20 µg/l (1-hr. average).

4.4.1.3    San Francisco Bay Sediment Quality

The Bay's sediment can be both a source of and sink for pollutants in the overlying water column. Past and present waste disposal practices from the surrounding land and waste discharges have resulted in the introduction of pollutants into the Bay, some of which have degraded Bay sediments. The overall influx of pollutants can cause increases in sediment pollutant levels. These pollutants are not distributed evenly in the Bay, and localized areas are highly contaminated. Natural resuspension processes, biological processes, other mechanical disturbances, dredging, and sediment disposal can remobilize particulate-bound pollutants. While pollutant loading to the Estuary from point sources has declined dramatically over the past two decades, and surface sediment contamination may be declining from historical highs, Bay sediments are still an important source and sink of pollutants. The mean concentrations of metals in sediments vary according to grain size, organic carbon content, and seasonal changes associated with riverine flow, flushing, sediment dynamics, and anthropogenic inputs. Anthropogenic inputs appear to have the greatest effect on sediment levels of copper, silver, cadmium, and zinc, but may also have elevated concentrations of chromium, nickel, and cobalt above background (RWQCB, 1994).

Sediment contamination concerns include:

• Various toxic contaminants found only in barely detectable amounts in the water column can accumulate in sediments to much higher levels

• Sediments serve as both a reservoir for contaminants and a source of contaminants to the water column and organisms

• Sediments integrate contaminant concentrations over time, whereas water column contaminant concentrations are much more variable and dynamic

• Sediment contaminants (in addition to water column contaminants) affect bottom-dwelling organisms and other sediment-associated organisms, as well as the organisms that feed on them and humans

• Results from the RMP, described in the previous section, has indicated that Estuary sediment is frequently toxic, and has shown no decrease in toxicity over time

A summary of sediment quality data from the 2003 RMP Annual Monitoring Results Report (SFEI, 2005b) for the entire Estuary is presented in Table 4.4-2. In Table 4.4-2, sediment quality data are compared to the NOAA sediment benchmarks termed Effects Range Low (ERL) and Effects Range Mean (ERM). The ERM is the concentration below which toxic or adverse effects in organisms living in the sediment are rarely observed, and above which adverse effects are frequently observed. Sediment concentrations greater than the ERM are generally interpreted as an indication of contamination.

4.4.1.3.1    Sediment Quality Along the Proposed Cable Route. The proposed HVDC cable would be buried under the Bay and extend between landing points near the San Francisco-based converter station and the Pittsburg converter station. The proposed route

TABLE 4.4-2
SAN FRANCISCO BAY SEDIMENT QUALITY SUMMARY

from San Francisco to Pittsburg lies within San Francisco Bay, San Pablo Bay, the Carquinez Strait, Suisun Bay, and New York Slough. The specific proposed route was selected with guidance from relevant agencies and organizations to avoid shipping channels, anchorages, known areas of sediment contamination, dredge disposal areas, and other known obstacles.

The Bay Protection and Toxic Cleanup Program (BPTCP) has identified sediment "toxic hot spots" where sediment dredging could result in the degradation of water quality in San Francisco Bay. The Bay Protection and Toxic Cleanup section of the California Water Code (Division 7, Sections 13390-13396.5) established a program to identify and plan remediation of toxic hot spots in bays and estuaries. Under this law, the RWQCB has implemented a program to identify potential toxic hot spots, sample and assess biological impacts in areas of unknown condition, confirm the biological impacts in areas that have been previously sampled, and assess the relationship between toxic pollutants and biological effects. In the Bay region, the RWQCB has reviewed existing data and reports; collected and analyzed new water, sediment, and tissue samples; and prepared reports. The Final Regional Toxic Hot Spot Cleanup Plan (RWQCB, 1999) summarizes the situation in the Bay, and identifies sites of concern and candidate toxic hot spots. The cable route for the proposed Project was designed to avoid known toxic hot spots.

Sampling Methodology. In order to confirm that cable installation along the proposed route would not disturb or disperse contaminated sediments (at levels above regulatory thresholds) that may be present along the proposed route, as well as guide selection of cable burying equipment and procedures, a Sampling and Analysis Program (SAP) of Bay floor sediments for the proposed Project was prepared (with regulatory guidance and approval from the San Francisco Dredged Materials Management Office) and implemented to complement and confirm existing data and surveys (refer to Appendix E of this EIR for more information). A total of 27 cores (twenty-three 6-foot cores and four 15-foot cores) were collected from the 27 sampling locations shown on Figure 4.4-2. Sampling was conducted from September 21 to 30, 2005 by URS field personnel and TEG Oceanographic Services, Santa Cruz, California, using a ship-mounted vibracore. One composite environmental sample was collected from each 6-foot core (23 samples) and two composite samples were collected from each 15-foot core (except one core which did not yield enough recovery for 2 samples). In addition, 4 duplicate sediment samples were analyzed for quality control purposes. The samples were analyzed for the chemicals displayed in Table 4.4-3.

TABLE 4.4-3
CONSTITUENTS ANALYZED
DURING SEDIMENT SAMPLING

Sediment Sampling Results. The sediment sampling results did not indicate elevated levels of chemicals with the exception of nickel. However, the naturally occurring concentrations of nickel in Bay Area sediments are much higher than the national sediment benchmarks as discussed below.

No pesticides, PCBs, or butyltins were detected in the sediment samples. All PAHs detected were well below the ERL benchmark.

Lead, cadmium, and silver were not detected at levels above the ERLs of 47, 1.2, and 1.0 mg/kg, respectively. The highest detected concentration of zinc was at the ERL of 150 mg/kg. Selenium was detected in approximately three-quarters of the samples, at concentrations up to 1.1 mg/kg. Arsenic, chromium, copper, and mercury were detected at concentrations above the ERLs, but below the ERMs.

Nickel concentrations in the samples ranged from 36 to 120 mg/kg, all of which are above the ERL of 20.9 mg/kg, and 29 samples had concentrations above the ERM of 51.6 mg/kg. The highest nickel concentrations (120 mg/kg) were in the samples from New York Slough near Pittsburg. While the concentrations of nickel are above the NOAA ERL and ERM benchmarks, they are not elevated compared to the ambient concentrations of chemicals in San Francisco Bay sediments developed by the RWQCB for Beneficial Reuse of Dredged Materials (RWQCB, 2000). Because nickel naturally occurs in Bay Area rock formations, the ambient concentration of nickel in Bay sediment is 112 mg/kg. Therefore, the range of 36 to 120 mg/kg is considered to be consistent with background concentrations.

Comparison to Regional Monitoring Program Data Near the Cable Route. Figure 4.4-2 shows sampling locations from the RMP along the proposed cable route. Sediment data from 10 RMP stations was compared to the results from the TBC sampling program (SFEI, 2005b,c). Table 4.4-4 presents a sediment data summary for locations along the proposed alignment.

With the exception of two samples, no PAHs, pesticides, or PCBs (total) were detected in the RMP samples at levels above the ERLs. The sample from RMP Station CB012S had 8 of the 17 analyzed PAHs at levels above the ERL but below the ERM. Station CB012S is located offshore of the Southeast Water Pollution Control Plant discharge, which extends offshore from the end of Pier 80 near the proposed (Western Pacific) laydown area. The sample from location CB073S (between Treasure Island and Angel Island) contained benzo(a)pyrene at a concentration just above the ERL. SU008S (Suisun Bay near Roe Island) had a dieldrin concentration above the ERL.

Cadmium, copper, lead, selenium, silver, and zinc were not detected above the ERLs. Arsenic was detected at levels from 2.8 to 11.5 mg/kg. The ERL for arsenic is 8.2 mg/kg and the ERM is 70 mg/kg. With the exception of one sample location where mercury was not detected, mercury was detected above the ERL but below the ERM for all samples. Mercury

TABLE 4.4-4
CABLE ROUTE SEDIMENT QUALITY SUMMARY^1,2,3

¹   All data are reported in mg/kg.
²   Data in bold = above ERL.
³   Data in bold and underlined = above ERM.

was not detected at sample location SU010S (Suisun Bay). Nickel was detected at concentrations above the ERM at all sample locations. The highest measured nickel concentration was 154 mg/kg at station SU008S (Suisun Bay).

In general, with the exception of RMP location CB012S, sediment results were comparable between the RMP stations along the alignment and the samples taken for the Project. Station CB012S is approximately 1,800 feet southeast of the cable route where the route turns towards the shore at milepost (MP) 0.4 (refer to Map A.2-1, sheet 1; and Figure 4.4-2). When data from this sample is discounted, only one PAH, acenaphthene, was detected above the ERL (but below the ERM) for the RMP stations along the alignment. The maximum concentrations when the CB012S results are not included are shown in the far rightmost column of Table 4.4-4.

4.4.1.4    Groundwater Quality

Groundwater is defined as subsurface water that occurs beneath the water table in soils and geologic formations that are fully saturated.

Coastal groundwater quality can be degraded through the intrusion of saltwater. Degradation of water quality reduces the groundwater basin yield, diminishing production from existing activities and limiting future groundwater development. In undeveloped coastal areas, saltwater is prevented from migrating landward by the hydraulic head of the fresh water, which must be high enough above sea level to compensate for the greater density of saltwater. Groundwater quality at each of the proposed Project sites is discussed in Section 4.4.1.6 below.

4.4.1.5.1    City of San Francisco. The majority of San Francisco is served by a combined storm sewer system where stormwater, along with residential and commercial sewage is directed to three wastewater treatment plants prior to being released to San Francisco Bay or the Pacific Ocean. The San Francisco Public Utilities Commission (SFPUC) treats and discharges approximately 84 million gallons per day of treated wastewater during dry weather to San Francisco Bay and the Pacific Ocean. During wet weather, with additional facilities and increased operations, the plants can treat approximately 465 million gallons of combined flows per day (SFPUC, 2005).

Flood hazard maps show that the proposed converter station site in San Francisco is located outside of the 100-year and 500-year floodplains and is not subject to flooding.

4.4.1.5.2    City of Pittsburg. Pittsburg's existing drainage system is comprised primarily of channelized creeks fed by surface runoff and underground storm drains. The City of Pittsburg maintains the system within incorporated areas (City of Pittsburg, 2001). Outside city limits, the responsibility lies with either Contra Costa County or the County Flood Control District.

The developed portions of the City of Pittsburg are within two major watersheds: Kirker and Lawlor Creeks (Figure 4.4-4). Lawlor Creek drains into Suisun Bay. Kirker Creek drains into New York Slough.

Kirker Creek originates in the hills in the southernmost end of the watershed and flows approximately 7 miles north through the city. The watershed covers approximately 8,539 acres. In the southern hills, the creek and its tributary channels have sufficient capacity to carry peak stormwater flows. Farther downstream, however, natural flow capacity declines as the creek channel flattens. Urbanization north of Buchanan Road further decreases capacity as the channel becomes restricted and enclosed by storm drain culverts. Reduction in permeable soils caused by development also increases the total volume and rate of runoff. Most runoff of the Lawlor Creek watershed is conveyed by natural channels, except for storm drains located in developed areas and culverts under State Route 4 (SR 4).

Annual rainfall in the Pittsburg planning area ranges from 12.5 inches along the Sacramento River to 17.5 inches in the southern hills. Average annual precipitation is 13 inches, nearly all of which falls between November and April, with the heaviest rainfall between December and February (City of Pittsburg, 2001). Much of the shoreline in the Pittsburg area is susceptible to storm flooding.

Flood hazard maps show that the proposed Standard Oil Converter Station site in Pittsburg is located outside of the 100-year and 500-year floodplains and is not subject to flooding.

4.4.1.6    Local Water Resources and Quality

4.4.1.6.1    San Francisco HWC Converter Station.The proposed San Francisco HWC Converter Station site and laydown areas are shown on Figure 4.4-3. The converter station site is located adjacent to the Bay. The proposed construction laydown site (Western Pacific) is also located adjacent to the Bay. There is no surface water on the HWC site. Stormwater from the site is currently directed to the San Francisco combined stormwater and sanitary sewer system.

Local groundwater levels are approximately 18 feet below ground surface (bgs). Groundwater at the site is known to be contaminated with petroleum hydrocarbons, including TPH. Groundwater contamination at the site is discussed further in Section 4.14, Hazardous Materials and Waste Management.

The alternative laydown area (Pier 94/96) is shown on Figure 4.4-3. There is no surface water on the site. Stormwater from the site is currently directed to the San Francisco combined stormwater and sanitary sewer system. Local groundwater levels at the alternative laydown area are expected to be similar to the HWC site (approximately 18 feet bgs). Groundwater flows to the southwest, south, and southeast direction.

4.4.1.6.2    Pittsburg Standard Oil Converter Station. The Standard Oil Converter Station site location is shown on Figure 4.4-5. It is approximately 3,800 feet south-southwest of New York Slough and 400 feet west of Dowest Slough and is situated in the Kirker Creek watershed. The southernmost edge of the site (at southernmost end of the proposed access road) is bordered by Kirker Creek, just north of the Pittsburg-Antioch Highway. The alternative Standard Oil construction laydown area (Delta Energy Center) is approximately 3,100 feet south of New York Slough and 400 feet west of Dowest Slough.

The proposed Pittsburg Standard Oil Converter Station site lies within the Pittsburg Plain Groundwater Basin, an 18-square-mile, elongated basin that runs east-west along and parallel to SR 4 (CDWR, 2003). This basin is bounded by Suisun Bay on the north, the Tracy Basin on the east, and the Clayton Basin on the west (CDWR, 2003). The southern boundary extends 1 to 3 miles inland from Suisun Bay.

The water-bearing units in the basin are Pleistocene to Recent age alluvial deposits up to 400 feet thick (CDWR, 2003). The water-bearing materials consist of lenticular beds of sand, gravel, and clay. Aquifers in the basin area are hydrologically connected to the Sacramento River. The groundwater flows in a northerly direction following the slope of the land to the below-sea-level aquifer that is part of the Sacramento/San Joaquin groundwater system (City of Pittsburg, 2001).

Geotechnical reports prepared for sites in the Pittsburg area indicate that groundwater levels vary considerably. Groundwater depth within upland areas of the Pittsburg Plain has been documented between 18 to 28 feet, whereas shallow groundwater (2 to 7 feet below ground surface [bgs]) may be encountered in low-lying areas near Suisun Bay and in ravines and creek channels. Shallow groundwater from seasonal saturation occurs in the upper 5 to 10 feet of surface soil and underlying bedrock (City of Pittsburg, 2001).

Shallower groundwater in low-lying areas near Suisun Bay and in ravines and creek channels is tidally influenced and tends to be saline with high mineral concentrations (City of Pittsburg, 2001). Intense pumping for industrial uses in the 1930s through 1950s resulted in overdraft and seawater intrusion. Limited amounts of water drawn from the underground aquifer are now blended with raw water from the Contra Costa Canal before treatment and distribution to the city. No subsurface investigations have been conducted on the site to determine groundwater quality. However, based on a Phase I Environmental Site Assessment conducted at the site, groundwater at the site may contain TPHs or other constituents. Potential groundwater contamination at the site is discussed further in Section 4.14, Hazardous Materials and Waste Management.

Stormwater currently flows from the site to its natural water course and then discharges into Kirker Creek. As described in Section 4.4.1.5 (Drainage and Flooding), Kirker Creek originates in the hills in the southernmost end of the watershed and flows approximately 7 miles north through the City of Pittsburg, draining into New York Slough.

4.4.1.6.3    Offshore DC Cable Route. The proposed HVDC cable would be buried under the Bay between a San Francisco-based converter station and the Pittsburg Converter Station. The proposed route lies within San Francisco Bay, San Pablo Bay, the Carquinez Strait, Suisun Bay, and New York Slough. Sediment quality along the cable route is described in Section 4.4.1.3.1 above (Sediment Quality Along the Proposed Cable Route).

4.4.2    Regulatory Setting

4.4.2.1    Federal

4.4.2.1.1    Clean Water Act. The Clean Water Act (CWA) empowers the EPA with regulation of wastewater and stormwater discharges into surface waters by using National Pollutant Discharge Elimination System (NPDES) permits and pretreatment standards. At the state level, these permits are issued by the RWQCBs, but the EPA may retain jurisdiction at its discretion. The CWA's primary effect on the proposed Project has to do with control of soil erosion during construction. The following federal regulations pertain to the CWA (33 USC 1251–1376).

Section 401. Dredging permit applicants intending to dispose material in water must obtain water quality certification from the State of California through the RWQCB with jurisdiction over the Project area. The RWQCB, after reviewing the Project, may recommend to the State Water Resources Control Board (SWRCB) that certification be granted or denied.

Dredged material considered for disposal in water must be tested to determine its suitability for disposal. Authority to determine suitability is exercised by the state under Section 401 of the CWA. The RWQCB defined its testing guidelines for wetland and upland beneficial reuse of dredged material in Interim Screening Criteria and Testing Requirements for Wetland Creation and Upland Beneficial Use (Wolfenden and Carlin, 1992). Those guidelines have been superseded by the Draft Staff Report Beneficial Reuse of Dredged Materials: Sediment Screening and Testing Guidelines (RWQCB, 2000).

Section 402. Drainage and runoff from proposed landside construction, including laydown areas, parking lots, and access roads, would likely add pollutants to stormwater discharges unless mitigation measures are implemented. Stormwater discharges associated with Project construction activities are regulated under the NPDES permitting system. Under the NPDES construction permit, owners of proposed projects where construction would disturb more than 1 acre of land would have to submit a Notice of Intent (NOI), develop a Stormwater Pollution Prevention Plan (SWPPP), conduct monitoring and inspections, retain monitoring records, report incidences of noncompliance, and submit annual compliance reports by July 1 of each year.

The State of California has permitting authority from the U.S., and the EPA implements the NPDES permit program. Stormwater NPDES permitting for certain classes of activities are regulated under the Industrial Activities General Permit adopted by the SWRCB on April 17, 1997 (WQO 97-03-DWQ NPDES Permit No. CAS000001). To comply with the conditions of this permit, facility operators are required to submit an NOI, develop a SWPPP, and conduct stormwater monitoring, in addition to submitting annual reports by July 1 of each year.

Stormwater discharges associated with construction activities are regulated under the General Construction Activity Stormwater Permit adopted by the State on August 19, 1999 (WQO 99-08 DWQ, NPDES Permit No. CAS000002). Under this permit, owners of land where a construction activity occurs that disturbs more than 1 acre of land must submit an NOI, develop an SWPPP, conduct monitoring and inspections, retain records of the monitoring, report incidences of noncompliance, and submit annual compliance reports.

Section 404. Dredged material disposal is regulated pursuant to Section 404 of the CWA, which requires authorization from the Secretary of the Army, acting through the U.S. Army Corps of Engineers (USACE), for the discharge of dredged or fill material into all waters of the United States, including wetlands. The USACE is mandated to protect and maintain navigable capacity of the nation's waters under 33 Code of Federal Regulations (CFR), Navigation and Navigable Waters. Section 33 CFR requires the USACE to issue permits for dredging and placement of dredged or fill material into the waters of the U.S. (Part 323), and for ocean dumping of dredged material (Part 324).

Dredging material for disposal at aquatic sites must undergo testing to determine its potential effects on the disposal site environment. Testing is also used to determine whether dredged material is suitable for unconfined aquatic disposal (SUAD). For disposal sites in or potentially affecting inland waters, such as San Francisco Bay, testing requirements are defined by Section 404 of CWA. Guidance for suitability testing procedures for inland waters is provided by the Evaluation of Dredged Material for Discharge in Inland and Near Coastal Waters – Testing Manual, also called Inland Testing Manual or ITM (EPA/USACE, 1998). For ocean disposal sites, suitability requirements are defined by 40 CFR 227.6. Guidance for suitability testing is provided by the Evaluation of Dredged Material Proposed for Ocean Disposal – Testing Manual, also known as the Green Book (EPA and USACE, 1991).

4.4.2.1.2    Rivers and Harbors Act of 1899 (33 USC 401 et seq.). The Rivers and Harbors Act of 1899 (33 USC 401 et seq.) regulates development and use of the nation's navigable waterways. Section 10 of the Act prohibits unauthorized obstruction or alteration of navigable waters, and vests regulatory authority in the Secretary of the Army, acting through the USACE, for work in, under, or over any navigable water of the U.S. The law applies to any dredging or disposal of dredged materials, excavation, filling, rechannelization, or any other modification of a navigable water of the United States.

4.4.2.1.3    Oil Pollution Act of 1990 (OPA) (33 USC 2701-2761). This is the principal statute governing oil spills into the nation's waterways. OPA was passed in the wake of the Exxon Valdez oil spill in March of 1989. The statute establishes liability and limitations on liability for damages resulting from oil pollution, and establishes a fund for the payment of compensation for such damages. In conjunction with CERCLA, OPA mandates a National Oil and Hazardous Substances Pollution Contingency Plan (NCP) to provide the organizational structure and procedures for preparing for and responding to discharges of oil and releases of hazardous substances, pollutants, and contaminants. OPA requires preparation of spill prevention and response plans by coastal facilities, vessels, and certain geographic regions. OPA amended the CWA and includes the Oil Terminal and Oil Tanker Environmental Oversight and Monitoring Act of 1990.

4.4.2.1.4    The Ports and Waterways Safety Act of 1972 (33 USC 1221 et seq.). As amended by the Port and Tanker Safety Act of 1978, this act provides the strongest authority for the United States Coast Guard's (USCG's) program to increase vessel safety and protect the marine environment in ports, harbors, waterfront areas, and navigable waters. It authorizes Vessel Traffic Services, controls vessel movement, and establishes requirements for vessel operation and other related port safety controls.

In addition, a number of other laws call for USCG enforcement. These include the Federal Water Pollution Control Act, which delegates enforcement authority and responsibility to the USCG in cases where oil and hazardous substances are discharged into U.S. waters in harmful quantities. The Act to Prevent Pollution from Ships (33 USC 1901 et seq.) limits the operational discharges of oil from ships and requires reception facilities to receive waste that cannot be discharged at sea. The Marine Protection, Research and Sanctuaries Act of 1972 (33 USC 1401 et seq.) requires USCG surveillance of ocean dumping activities. The Oil Pollution Act of 1990 (33 USC 2701 et seq.) requires increased USCG involvement with vessel traffic service systems, vessel and facility monitoring, and oil spill prevention and cleanup, in addition to amending the Federal Water Pollution Control Act.

NOAA established the Damage Assessment and Restoration Program (DARP) in 1990 to fulfill natural resource trustee responsibilities assigned in the CWA, CERCLA, OPA, NMSA, and other federal laws. DARP has the mission to restore coastal and marine resources that have been injured by releases of oil or hazardous substances and to obtain compensation for the public's lost use and enjoyment of these resources.

4.4.2.1.5    Marine Protection, Research, and Sanctuaries Act of 1972 (MPRSA) (16 USC 1431 et seq.). Section 103 of the MPRSA of 1972, as amended, requires authorization from the Secretary of the Army, acting through the USACE, for the transportation of dredged material for the purpose of ocean disposal. The EPA is charged with providing oversight of the USACE's regulatory program and maintaining the integrity of the nation's waters. The EPA has responsibility for designating ocean disposal sites. According to the MPRSA, the EPA oversees disposal of materials into ocean waters and must provide written concurrence before material can be disposed in the ocean.

4.4.2.2    State

4.4.2.2.1    Water Quality Control Act (Porter-Cologne Act) (California Water Code Section 13000 et seq.; CCR Title 23, Chapter 3, Subchapter 15). Under this act, the RWQCB may also act by either issuing or waiving waste discharge requirements for dredging projects with upland disposal of dredged material. These actions by the RWQCB are not equivalent to issuing or waiving water quality certification. The RWQCB must issue a separate 401 Certification.

The SWRCB, as authorized by the act, has promulgated regulations in Subchapter 15 of Title 23 of the California Code of Regulations (CCR) designed to protect water quality from the effects of waste discharges to land. Under Subchapter 15, wastes that cannot be discharged directly or indirectly to waters of the state (and therefore must be discharged to land for treatment, storage, or disposal) are classified to determine specifically where such wastes may be discharged.

In addition to the provisions contained in the Lempert-Keene-Seastrand Oil Spill Prevention and Response Act, the California Department of Fish and Game (CDFG) Code provides general law regarding water pollution prohibitions and both criminal and civil penalties on discharges of petroleum and other hazardous materials entering California waters (Sections 5650 et seq.). State Fish and Game wardens enforce these sections.

Further, California Water Code Section 13272 requires any person who knows of any oil or petroleum product discharge into California waters to notify the Office of Emergency Services (OES). Failure to comply is a misdemeanor.

All Oil Spill Prevention and Response regulations are found in Title 14, CCR. Regulations promulgated by the State Lands Commission are found in Title 2, CCR.

California State Lands Commission Marine Facilities Division (MFD) derive legislative authority from the Lempert-Keene-Seastrand Oil Spill Prevention and Response Act of 1990 Division 7.8 of the Public Resources Code. The act expanded the State Lands Commission's (SLC's) pollution prevention responsibilities.

4.4.2.2.2    State Lands Commission (Public Resources Code Section 6001 et seq.). Projects involving use of state lands may require lease or permitting from the SLC, which is charged with managing California's sovereign lands for purposes consistent with the public trust.

4.4.2.2.3    Dredged Materials Management Office (DMMO) Dredging Permit. Dredging and dredge disposal would require a permit issued by DMMO. In addition, a CWA Section 401 Certification would be required from RWQCB for dredging to ensure that proposed dredging would not impair water quality and Section 7 Biological Consultation (e.g., with the National Marine Fisheries Service [NMFS]) could be required.

4.4.2.3    Local

4.4.2.3.1    McAteer-Petris Act (Public Resources Code Section 66600 et seq.). The Bay Conservation and Development Commission (BCDC) regulates dredging and disposal under the provisions of the McAteer-Petris Act. BCDC, on the basis of the Suisun Marsh Preservation Act of 1977 (Public Resources Code Section 29000-29612SB 1981) and the federal Coastal Zone Management Act (CZMA) (33 USC 1451 et seq.), is mandated to reduce Bay fill and to protect and manage the coastal zone resources of San Francisco Bay. The BCDC's jurisdiction includes the Bay and a 100-foot shoreline band, salt ponds, managed wetlands, tidal marshes 5 feet above mean sea level, and certain named tributary waterways, such as rivers. According to the San Francisco Bay Plan, BCDC can authorize dredging when it can be demonstrated that the dredging is needed to serve a water-oriented use or other important public purpose, the materials to be dredged meet the water quality requirements of the RWQCB, important fisheries and natural resources would be protected through seasonal restrictions established by CDFG, USFWS, and/or NMFS, dredging is minimized through project siting and design, and the materials would, if feasible, be reused or disposed outside the Bay and certain waterways. The amendments to the Water Quality Control Plan for the San Francisco Bay Basin focus on regulating the known and potential impacts to water quality, and beneficial uses of those waters by disposal activities.

4.4.2.3.2    Pittsburg Municipal Code (Chapter 15.104 – Stormwater Management Plan for Kirker Creek Watershed Drainage Area). Prior to the completion of planned, non-Project related downstream improvements to the Kirker Creek Watershed, the addition of new impervious surface areas in the Kirker Creek Watershed create a substantial risk of flooding. The Standard Oil Converter Station site is located at the downstream end of the Kirker Creek Watershed, and adjacent to, Dowest Slough, and the point at which the Kirker Creek Watershed discharges into the New York Slough. In accordance with the requirements of the Pittsburg Municipal Code (Chapter 15.104) and the Contra Costa Clean Water Program Stormwater C.3 Guidebook, this new development must:

• Construct an onsite infiltration system, associated with small storm flows, that would detain and control the rate of stormwater runoff to the adjacent Kirker Creek Watershed

4.4.3    Environmental Impacts

This section discusses potential Project-related onshore and offshore impacts to water resources and quality, including the criteria used to assess potential impact significance.

4.4.3.1    Thresholds of Significance

Based on CEQA Guidelines (Appendix G), Project-related impacts to water resources are considered to be potentially significant if they would:

• Violate any water quality standards or waste discharge requirements

• >Substantially deplete groundwater supplies or interfere substantially with groundwater recharge

• Substantially alter the existing drainage pattern of the site or area in a manner which would result in substantial erosion or siltation on- or offsite

• Substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or offsite

• Create or contribute runoff water that would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff

• Otherwise substantially degrade water quality

4.4.3.2    San Francisco HWC Converter Station

4.4.3.2.1    Construction-related Impacts. The proposed HWC Converter Station site, onshore AC cable route, and temporary construction laydown area are shown on Figure 4.4-3.

Erosion and Contaminated Runoff. Stormwater on the site is currently directed to the San Francisco combined stormwater and sanitary sewer system. Stormwater and sanitary discharges for the converter station would also be discharged to the City of San Francisco's combined collection and treatment system. Stormwater falling in contained areas would pass through oil-water separators and the clear-well water would be discharged to the combined sewer system.

Onshore construction activities at the converter station site and proposed and alternative construction laydown areas could increase the potential for uncontrolled runoff of stormwater contaminated with sediments or other pollutants that could impact surface water quality and sedimentation. Construction of the proposed Project could increase the potential for silts to impact the water quality of San Francisco Bay through both suspended solids and water quality contaminants. Operation and maintenance of the facility could impact surface water quality of San Francisco Bay through inadvertent spills or discharges.

Stormwater pollution occurs when rainwater comes into contact with materials onsite and washes contaminants into storm drains, creeks, or directly into the Bay. Sources of pollution during Project construction could include oil leaked from heavy equipment and vehicles, grease, hydraulic fluid, fuel, construction materials and products, waste materials, landscaping runoff containing fertilizers, pesticides, or weed killers, and erosion of disturbed soil.

Stormwater discharges associated with Project construction activities are regulated according to CCR Section 402(p). Under the NPDES construction permit, owners of the proposed locations where construction would disturb more than 1 acre of land would have to submit an NOI, develop an SWPPP, conduct monitoring and inspections, retain monitoring records, report incidences of noncompliance, and submit annual compliance reports by July 1 of each year.

Impact WATER-1: Erosion and Contaminated Runoff. Erosion and contaminated runoff during construction and operation could significantly impact water quality within San Francisco Bay. This is considered a potentially significant impact.

Mitigation Measure WATER-1: Erosion Control and Contaminant Source Control. Apply for and comply with NPDES construction permit, and Industrial Activities General Permit. Requirements for the permits include submittal of a Notice of Intent, development of a Stormwater Pollution Prevention Plan (SWPPP), monitoring and inspections, and submittal of annual compliance reports.

Implementation Responsibility:  Project proponent/construction contractor

Requirements and Timing:         SWPPP shall be developed by construction contractor, or qualified consultant prior to commencement of construction; General Construction Activity Stormwater Permit adopted by the State on August 19, 1999 (WQO 99-08 DWQ, NPDES Permit No. CAS000002) prior to commencement of construction

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Mitigation Measure WATER-1 would reduce Impact WATER-1 to a less-than-significant level.

Horizontal Directional Drilling (HDD). The directional drilling location for the HWC Converter Station site is shown on Figure A.4-9 (Appendix A) and is located on the southeast portion of the site near the edge of the Bay. Construction activities using HDD could impact Bay water quality through loss of drilling fluids and disruption of Bay bottom sediment at the sediment surface where the borehole emerges. It is possible that a small amount of drilling mud (also known as drilling fluid) and disturbed sediment could be released into the Bay at the HDD location. Drilling mud would consist of water, bentonite clay, and inert, non-toxic polymers. Construction activities using HDD could also impact groundwater quality through loss of drilling mud that would increase suspended material in groundwater.

Impact WATER-2: Surface Water Quality Impacts from HDD. HDD could have significant water quality impacts through loss of drilling fluids and disruption of Bay bottom sediment at the sediment surface where the borehole emerges. This is considered a potentially significant impact.

Mitigation Measure WATER-2: Spill Prevention and Control Plan for HDD. Drilling shall be performed in accordance with a site-specific Spill Prevention and Control (SPCC) Plan for HDD Operations for Drill Fluids and Cuttings. Spill response measures included in this plan, should a spill occur, shall include reducing fluid pressures, thickening the fluid mixture, and/or adding pre-approved loss circulation materials (LCMs) to the mixture.

Implementation Responsibility:  Project proponent/HDD contractor, in conjunction with the cable laying firm

 Requirements and Timing:        Prepare SPCC plan prior to commencement of construction

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

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

Impact WATER-3: Groundwater Quality Impacts from HDD. HDD could have significant water quality impacts through loss of drilling fluids that would increase suspended material in groundwater. This would be considered a potentially significant impact.

Mitigation Measure WATER-3: Use of Pilot Hole and Reaming. HDD shall be performed using a pilot hole plus reaming technique to minimize the potential for impacts to groundwater. To prevent significant water quality impacts, drilling muds shall consist of naturally occurring materials such as water and bentonite clay, plus inert, non-toxic polymers.

Both the drilling technique and early detection and response shall be used to minimize release of fluids to the environment. HDD shall start with completion of a small-diameter pilot hole. The pilot hole is gradually enlarged using reaming. This technique acts to prevent sudden loss of large volumes of drilling fluids.

Early detection and rapid response shall be implemented to minimize loss of drilling fluids. In the event loss of drilling fluids is detected, natural LCMs such as cotton dust, cottonseed hulls, wood fiber, mica, and cedar fiber shall be added to the drilling fluid. Alternative actions that shall be considered and implemented, as required, include reduction in drilling pressure, thickening of the fluid mixture, and construction of spill control structures, pits, and silt fences onshore, or silt curtains offshore.

Implementation Responsibility:  Project proponent/HDD contractor, in conjunction with the cable laying firm

Requirements and Timing:         Monitor for loss of drilling fluids and implement SPCC Plan, as applicable, during drilling

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

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

Spills and Discharges. Groundwater resources at the site are not used for drinking water or other purposes. However, construction of the facility would require the use of petroleum products and hazardous materials and would generate solid waste. Inadvertent spills or discharges or improper handling of these materials could affect surface water or groundwater quality. Impacts and Mitigation Measures associated with accidental spills and waste management during operation are addressed in Section 4.14, Hazardous Materials and Waste Management. These Mitigation Measures (HAZ-3, HAZ-4, HAZ-5) include development of a Spill Prevention, Control and Countermeasure Plan and waste management protocols for construction areas.

4.4.3.2.2    Operations-related Impacts.

Flooding. Some areas along the shoreline and drainages leading to the Bay are potential floodplains. Risks associated with building in a floodplain include threats to life and property. Local city or county government agencies regulate floodplain development through land use controls, based on determinations of flood elevations. The Federal Emergency Management Agency (FEMA) maintains maps of 100-year flood areas in the Bay Area counties. A "100-year flood" refers to a flood level with a 1 percent or greater chance of being equaled or exceeded in any given year (Figure 4.4-4).

A review of FEMA records indicates that San Francisco is not listed as a Special Flood Hazard Area (SFEC, 1994). Additionally, the City and County of San Francisco are not part of FEMA's National Flood Insurance Program.

Based on a USACE Tidal Stage versus Frequency Study (1984), the 100-year tide level in the area of Hunters Point/India Basin was 6.7 feet National Geodetic Vertical Datum (NGVD) (SFEC, 1994). Based on the wind-generated wave runup calculations reported in SFEC (1994) for a site near Hunters Point (based on an effective fetch of 5.7 miles and annual average peak wind speeds from San Francisco International Airport), the calculated maximum runup, including the maximum 100-year tide, wind runup, wind setup and mean higher high water (MHHW) tide level, is 16.1 feet above mean lower low water (MLLW). The lowest site elevation is approximately 20 feet above MLLW. Therefore, the potential flooding hazard is considered to be less than significant.

Spills and Discharges. Groundwater resources at the site are not used for drinking water or other purposes. However, operation and maintenance of the proposed facility would require the use of petroleum products and minor quantities of hazardous materials in addition to generating solid wastes. Inadvertent spills or discharges or improper handling of these materials could affect surface water or groundwater quality. Impacts and Mitigation Measures associated with accidental spills and waste management during operation are addressed in Section 4.14, Hazardous Materials and Waste Management. These Mitigation Measures (HAZ-8, HAZ-9, HAZ-10) include development of a Hazardous Materials Business Plan and waste management protocols for the converter station sites.

4.4.3.3    Pittsburg Standard Oil Converter Station

4.4.3.3.1    Construction-related Impacts. The proposed Pittsburg Standard Oil Converter Station site, onshore AC/DC cable routes, temporary proposed and alternative construction laydown areas, and proposed and alternative access roads are shown on Figure 4.4-5.

An area of up to approximately 7 acres located on vacant property adjacent to and north of the site would be devoted to equipment and materials laydown, storage, parking of construction equipment, small fabrication areas, and office trailers for the Pittsburg Standard Oil Converter Station site. General Project parking would be located at the laydown area.

The proposed access road for the site would include a bridge crossing at Kirker Creek just north of the Pittsburg-Antioch Highway. The bridge would be a single span, 80-feet long, 30-feet wide, and would accommodate a 10-foot rise in elevation from south to north. The concrete abutments on each end of the bridge would be supported on piles, if required. Kirker Creek is channelized but unlined in the location of the proposed access road bridge and it drains upstream areas including nearby industrial properties and the Pittsburg-Antioch Highway. The bridge would be designed and constructed to avoid the potential for slope failure and hence erosion which could degrade water quality in Kirker Creek.

Most stormwater from the converter station site would continue to flow along its natural watercourse into Kirker Creek. Stormwater falling onto paved and contained areas such as transformers would pass through oil-water separators and the clear-well water would be discharged to its natural watercourse in a manner that would control discharge velocity and the potential for erosion.

Erosion and Contaminated Runoff. Onshore construction activities at the converter station, proposed and alternative access roads, and proposed and alternative laydown areas could increase the potential for soil erosion and uncontrolled runoff of stormwater contaminated with sediments or other pollutants that could impact surface water quality and sedimentation. Construction of the proposed Project could increase the potential for silts to impact the water quality of Kirker Creek, New York Slough, and San Francisco Bay through both suspended solids and water quality contaminants. Operation and maintenance of the facility could impact surface water quality of the aforementioned water bodies through inadvertent spills or discharges.

Stormwater pollution occurs when rainwater comes into contact with materials on site and washes contaminants into storm drains, creeks, or directly into the Bay. Sources of pollution during Project construction could include oil leaked from heavy equipment and vehicles, grease, hydraulic fluid, fuel, construction materials and products, waste materials, landscaping runoff containing fertilizers, pesticides or weed killers, and erosion of disturbed soil.

Stormwater discharges associated with Project construction activities are regulated according to CCR Section 402(p) under NPDES. Under the NPDES construction permit, owners of the proposed converter station locations where construction would disturb more than 1 acre of land would have to submit an NOI, develop an SWPPP, conduct monitoring and inspections, retain monitoring records, report incidents of noncompliance, and submit annual compliance reports by July 1 of each year.

Impact WATER-1: Erosion and Contaminated Runoff. The erosion control and runoff impact (Impact WATER-1) described in Section 4.4.3.2.1 applies at the Pittsburg Standard Oil Converter Station site.

Mitigation Measure WATER-1: Erosion Control and Contaminant Source Control. Mitigation Measure WATER-1 described in Section 4.4.3.2.1 shall be applied for the Pittsburg Standard Oil Converter Station site.

Implementation Responsibility:  Project proponent/construction contractor

Requirements and Timing:         SWPPP shall be developed by construction contractor, or qualified consultant. General Construction Activity Stormwater Permit adopted by the State on August 19, 1999 (WQO 99-08 DWQ, NPDES Permit No. CAS000002) prior to commencement of construction

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Mitigation Measure WATER-1 would reduce Impact WATER-1 to a less-than-significant level.

Directional Drilling (HDD). HDD would be used at the shore crossing for the AC/DC cable installation to the Standard Oil site and beneath Kirker Creek. The directional drilling locations for the site are shown on Figure A.4-10 (Appendix A) for the shore crossing and Map A.2-1 (Sheet 10 of 10) for the HDD crossing of Kirker Creek.

HDD could impact Bay water quality through loss of drilling fluids and disruption of Bay bottom sediment at the sediment surface where the borehole emerges. It is possible that a small amount of drilling muds and disturbed sediment could be released at the HDD location. Such releases are known as "frac-out." It is also possible that a small amount of drilling muds could be released to Kirker Creek if frac-out occurred. Drilling mud would consist of water, bentonite clay and inert, non-toxic polymers.

Impact WATER-2: Surface Water Quality Impacts from HDD. Impact WATER-2 described in Section 4.4.3.2.1 applies at the Pittsburg Standard Oil Converter Station site.

Mitigation Measure WATER-2: Spill Prevention and Control Plan for HDD. Mitigation Measure WATER-2 described in Section 4.4.3.2.1 shall be applied for the Pittsburg Standard Oil Converter Station site.

Implementation Responsibility: Project proponent/HDD contractor, in conjunction with the cable laying firm

Requirements and Timing:         SPCC Plan prepared prior to commencement of construction; HDD contractor to monitor for potential spills and implement remedial contingency plan, as applicable

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

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

Impacts to Kirker Creek. HDD would also be used to pass under Kirker Creek, a dry waterbed except during rainfall events. If frac-out occurred, drilling mud could be released into the creek causing a water quality impact. This event would constitute a potentially significant impact.

Impact WATER-3: Groundwater Quality Impacts from HDD. Groundwater quality impacts from HDD (Impact WATER-3) described in Section 4.4.3.2.1 applies to the proposed subsurface Kirker Creek crossing associated with the onshore cable route at the Pittsburg Standard Oil Converter Station site.

Mitigation Measure WATER-3: Use of Pilot Hole and Reaming. Mitigation Measure WATER-3 is applicable at the Kirker Creek crossing for the Pittsburg Standard Oil Converter Station site.

Implementation Responsibility:  Project proponent/HDD contractor in conjunction with the cable laying firm

Requirements and Timing:         Monitor for loss of drilling fluids and implement SPCC Plan, as applicable; during drilling

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

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

Spills and Discharges. Groundwater resources at the site are not used for drinking water or other purposes. However, construction of the facility would require the use of petroleum products and hazardous materials and would generate solid waste. Inadvertent spills or discharges or improper handling of these materials could affect surface water or groundwater quality. Impacts and Mitigation Measures associated with accidental spills and waste management are addressed in Section 4.14, Hazardous Materials and Waste Management. These Mitigation Measures (HAZ-3, HAZ-4, HAZ-5) include development of a Spill Prevention, Control and Countermeasure Plan and waste management protocols for construction areas.

Kirker Creek Watershed Drainage Area. The proposed Standard Oil Converter Station site, the proposed onshore AC/DC cable routes that connect to New York Slough, the proposed and alternative laydown areas, and the proposed and alternative access roads are all within the Kirker Creek Watershed (Figure 4.4-4). Project construction and operations could increase runoff to the creek.

Impact WATER-4: Impacts to Kirker Creek Watershed Drainage Area. Construction and operations of the Standard Oil Converter Station, onshore AC/DC cable routes, laydown areas, and access roads are all within the Kirker Creek Watershed. Project construction and operations could increase runoff to the creek. This impact is considered potentially significant.

Mitigation Measure WATER-4: Kirker Creek Stormwater Management. Comply with Pittsburg Municipal Code (Chapter 15.104 – Stormwater Management Plan for Kirker Creek Watershed Drainage Area) which states that new development within the Kirker Creek Watershed Drainage Area must:

• Construct an onsite infiltration system, associated with small storm flows, that would detain and control the rate of stormwater runoff to the adjacent Kirker Creek Watershed

Implementation Responsibility:  Project proponent

Requirements and Timing:         Must be completed in conformance with the Pittsburg Municipal Code Stormwater Management Plan for Kirker Creek prior to completion of final design, City of Pittsburg Design Review and prior to commencement of construction

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Mitigation Measure WATER-4 would reduce Impact WATER-4 to a less-than-significant level.

4.4.3.3.2    Operations-related Impacts.

Flooding. Some areas along the shoreline and drainages leading to the Bay are potential floodplains. Risks associated with building in a floodplain include threats to life and property. Local city or county government agencies regulate floodplain development through land use controls, based on determinations of flood elevations. FEMA maintains maps of 100-year flood areas in the Bay counties. A "100-year flood" refers to a flood level with a 1 percent or greater chance of being equaled or exceeded in any given year. As shown on Figure 4.4-4, the Standard Oil site is not located within the FEMA 100-year floodplain. Therefore, the risk of flooding is considered less than significant.

Spills and Discharges. Groundwater resources at the site are not used for drinking water or other purposes. However, operation and maintenance of the facility would require the use of petroleum products and minor quantities of hazardous materials and would generate solid waste. Inadvertent spills or discharges or improper handling of these materials could affect surface water or groundwater quality. Impacts and Mitigation Measures associated with accidental spills and waste management are addressed in Section 4.14, Hazardous Materials and Waste Management. These Mitigation Measures (HAZ-8, HAZ-9, HAZ-10) include development of a Hazardous Materials Business Plan and waste management protocols for the converter station sites.

4.4.3.4    Offshore DC Cable Route

4.4.3.4.1    Construction-related Impacts. The proposed Project would involve construction and operation of approximately 56 miles of HVDC cable buried in the bottom of San Francisco Bay. Refer to Figure 4.4-2 for an overview of the proposed submarine cable route, including delineation of a 500-meter-wide study corridor that is centered on the cable route over the majority of its length.

Cable Placement. The cable would be laid using the Cable Ship (C/S) Giulio Verne (or equivalent) in deeper waters and using a barge in shallower waters. To the greatest extent possible, a Hydroplow or equivalent technology towed behind the cable-laying vessel or barge would be used to bury the cable at the targeted depth of 3 to 6 feet below the Bay bottom. The Hydroplow's "stinger" fluidizes bottom sediments and carries the cable to the bottom of the fluidized trench.

It is expected that the cable would be laid in two sections. The section between Potrero and a point east of the Benicia Bridge would be laid using the C/S Giulio Verne, which has an operation draft of 10 meters. In shallower waters in Suisun Bay and possibly also across the Pinole Shoals, the cable would be laid from a barge. Up to three potential splice locations (refer to Map A.2-1) are indicated pending final detailed design. It takes approximately 10 days to complete a single splice.

Hydroplow operations would produce a light sediment plume and locally increased turbidity. The plume is estimated to represent approximately 10 to 20 percent of the displaced sediment and would be expected to dissipate rapidly as the Hydroplow proceeds, leaving little or no spoil pile ridges alongside the trench. This percentage is an indicative figure which could vary depending on soil conditions, trench depth, etc. Over the approximately 56-mile-long submarine cable alignment, approximately 70,000 yd³ would be fluidized by the Hydroplow, resulting in 7,000 to 14,000 yd³ of ejected material. If the fluidized materials were contaminated, however, they have the potential to create water quality impacts. Hence, sediment quality data are required to assess this possibility.

Shallower water depths in the Pinole Shoals area of the alignment limit the ability of the Giulio Verne to both lay and bury the cable in this area. Consequently, a two-step operation of cable laying followed by a separate burial activity would be used in this area. This two-step operation would not be required if a barge were used for cable installation across the Pinole Shoals. First, the cable would be laid on the Bay bottom using the Giulio Verne, and second, a Hydroplow or equivalent technology pulled behind the barge would perform post-placement. The second type of Hydroplow ejects approximately 20 percent of material from the trench. This percentage could vary due to soil conditions, trench depth, etc.

Dredging. At two locations along New York Slough, the cable route crosses the shipping channel which is currently maintained to a water depth of 35 feet. Based on discussion with the USACE, this section of channel may eventually be deepened to 45 feet as has been proposed in the San Francisco to Stockton Phase III (John F. Baldwin) Navigation Channel Project (USACE, 1998). To allow for overdredging during future maintenance dredging of the shipping channels, it has been recommended that the cable be laid on the order of 15 to 20 feet, with the potential for burial to be greater if required, below the existing channel bottom.

Limited dredging would be required in two locations in order to bury the HVDC cable at a depth of greater than 15 feet, as this depth is beyond the reach of the Hydroplow or equivalent technology. The first location is at the west end of the West Reach, northeast of the Mirant Pittsburg Power Plant. This location is at approximately MP 52.4 - 52.5 (refer to Map A.2-1, Sheet 10 of 10, Appendix A). The second location is just east of the Dow Chemical Plant property in Pittsburg at approximately MP 55.9 - 56.0 (refer to Map A.2-1, Sheet 10 of 10, Appendix A). At these locations, the proposed DC/AC cables would cross the existing shipping channel in New York Slough. The channel in these areas is between 45 and 50 feet deep. USACE routinely performs maintenance dredging in these areas.

The requirement to excavate a cable trench is similar in both areas. At each location, it would be necessary for the dredge to excavate approximately 38,000 cubic yards. These excavations would provide a trench that is approximately 400 feet long by 30 feet wide at the bottom of the excavation by 15 - 20 feet deep beneath the Bay floor, in which the two cables would be installed using the Hydroplow or equivalent technology to achieve the targeted burial depth. The sides of the trenches would be sloped at 4 feet horizontal to 1 foot vertical. It is currently planned that the trench would be backfilled after the cables were installed.

The dredging method would utilize a barge-mounted crane excavating with a clamshell bucket. Excavated material would be brought to the surface and deposited in a barge. The USACE and private firms use this method to perform maintenance dredging of shipping channels and ship docks in the area.

During the dredging process, material that is excavated and loaded on the barge would be sampled and tested in a laboratory to determine its acceptability for reuse as backfill. If the excavated material is determined to be acceptable, the material would be stored until the HVDC and HVAC cable installation was complete. At that time, the excavated material would be returned to the bottom of New York Slough as backfill. If testing determined that the material was unacceptable for reuse as backfill, the material would be brought to an acceptable disposal site. One possible use for such material is to support ongoing wetland reclamation projects in the area. If the excavated material was unacceptable for use as backfill, the excavated area would be expected to fill naturally over time.

The dredging schedule, along with all cable laying activities in the Bay, would be coordinated with USACE, the USCG, the San Francisco Bar Pilots, and all other designated agencies. The time required to excavate both trenches is estimated to be approximately 2 weeks. Backfilling after the cables are in place is anticipated to take four to five days. This working schedule would be coordinated to ensure that the normal flow of ship traffic in the area was maintained.

Water Quality Impacts from Hydroplow. Use of the Hydroplow or equivalent technology could result in temporary and transient localized increases in turbidity as well as resuspension of contaminated sediments if they occur along the cable route.

The increase in turbidity would be very localized and would not be expected to significantly impact water quality. Experience on other cable-laying projects using a Hydroplow or equivalent technology indicates approximately 10 to 20 percent of the fluidized sediments would be dispersed during cable laying. The cable is scheduled to be installed over a period of approximately 4 to 5 months. It is expected that cable installation using the Giulio Verne would proceed at a faster rate than installation using a barge.

The anticipated volume of suspended sediment is small compared to the volume of sediment resuspended in San Francisco Bay during the monthly spring tides or during wind-storm events. Each major tidal event or storm event resuspends over 1 million cubic yards of sediment (assuming an average 200 mg/L suspended sediment concentration during the events – see McKee et al., 2002). Because the sediments in San Francisco Bay are very dynamic, the local disturbance of a small volume of sediment is not considered to be potentially significant.

As previously described, the cable route was chosen to avoid known sediment "toxic hot spots," identified in San Francisco Bay by BPTCP, where sediment dredging could result in the degradation of water quality. Because toxic hot spots are associated with land-based industrial activities, the proposed cable route was located in deep water as far offshore as possible.

A sediment sampling program was performed along the cable route as described in Section 4.4.1.4 and Appendix E. The sample locations and RMP locations are shown on Figure 4.4-2. Both the Project-specific sediment sampling program and the RMP data indicate that the sediment along San Pablo Bay, Carquinez Strait, Suisun Bay, and New York Slough portions of the proposed cable route is not contaminated. While elevated nickel levels (compared to NOAA sediment benchmarks) were recorded near New York Slough, the ambient nickel concentrations in San Francisco Bay are more than twice the NOAA ERM value. The maximum nickel concentrations are close to ambient levels and are not considered significant.

The RMP data recorded at station CB012S (near the HWC site laydown area [Western Pacific]) shows elevated levels of PAHs. Nearshore elevated PAH concentrations were also recorded offshore of the Potrero Power Plant in San Francisco (URS, 2001). HDD or Hydroplow or equivalent technology activities near either of these locations could encounter elevated PAH levels.

Impact WATER-5: Water Quality Impacts from Cable Laying Operation. Nearshore and offshore sediment in the Potrero area is contaminated with elevated levels of PAHs. Disturbance of these sediments could result in substantial water quality impacts. This would be considered a potentially significant impact.

Mitigation Measure WATER-5: Avoidance of Sediment Contamination. To avoid potential known nearshore and offshore sediment contamination, the HDD shall be completed as far offshore as is feasible and remote from RMP station CB012S near Potrero Point in San Francisco. Hydroplow or equivalent technology activities shall also avoid known contamination in the area of station CB012S. Confirmation sediment sampling shall be performed at the location where the HDD emerges into the Bay and the results would be considered and addressed prior to commencement of construction near this location.

Implementation Responsibility:  Project proponent/HDD contractor in conjunction with the cable laying firm; during the final design process

Requirements and Timing:         Prior to completion of final design and initiation of construction

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance

Resulting Level of Significance. Mitigation Measure WATER-5 would reduce Impact WATER-5 to a less-than-significant level.

Dredging and Dredge Material Disposal. As described in Section 4.4.1.4, four 15-foot sediment cores were obtained during the sediment sampling program for this Project; two cores were obtained in each proposed dredge area. No pesticides, PCBs, or butyltins were detected in the sediment samples. All PAHs detected were well below the ERLs.

The following discussion regarding Bay sediment has also been described in table form. Table 4.4-2 summarizes sediment quality in the San Francisco Bay based on core samples taken. Table 4.4-3 details what chemicals were analyzed for and by what method. Table 4.4-4 summarizes the sediment quality along the proposed cable route more specifically.

At the proposed dredge locations, lead, mercury, cadmium, silver, and zinc were not detected at levels above the ERLs of 47, 0.15, 1.2, 1.0, and 150 mg/kg, respectively. Selenium was detected in half of the samples, at concentrations up to 1.1 mg/kg. There is no published ERL for selenium. Arsenic, chromium, and copper, were detected at concentrations above the ERLs, but below the ERMs.

Nickel concentrations in the samples ranged from 45 to 120 mg/kg, all of which are above the ERL of 20.9 mg/kg. The highest nickel concentrations (120 mg/kg) were in the samples from New York Slough (NYW-2, NYE-1, and NYE-2). While the concentrations of nickel are above the NOAA ERL and ERM benchmarks, they are not elevated compared to the Ambient Concentrations of chemicals in San Francisco Bay sediments developed by the RWQCB for Beneficial Reuse of Dredged Materials (RWQCB, 2000). Because nickel naturally occurs in Bay Area rock formations, the ambient concentration of nickel in Bay sediment is 112 mg/kg. Therefore, the range of 36 to 120 mg/kg is considered to be consistent with background concentrations.

Dredging and the disposal of sediments have the potential to directly affect the health of the Bay because these activities can remobilize previously deposited particulate-bound pollutants. For this reason, regulatory controls greatly restrict new activities that might require dredging/dredge material disposal in the Bay.

Sediment testing and removal would be conducted in accordance with a consolidated Dredging – Dredge Material Reuse/Disposal permit that would need to be applied for and issued by the San Francisco DMMO. The permit covers both Section 404 and Section 10 dredging permits and is functionally equivalent to an RWQCB Report of Waste Discharge, pursuant to Article 4, Chapter 4 of the Porter-Cologne Water Quality Control Act. In accordance with this permit, a dredged sediment testing program would be conducted. Non-compliance with these regulatory controls could result in significant impacts to water quality in the Bay.

Impact WATER-6: Water Quality Impacts from Dredging and Dredge Material Disposal. Dredging at two locations in New York Slough and disposal of the dredge material has the potential to significantly impact water quality in the Bay.

Mitigation Measure WATER-6: Dredging Controls and Sediment Testing Program. A consolidated Dredging – Dredge Material Reuse/Disposal permit shall be obtained through the San Francisco DMMO. In accordance with this permit, a dredged sediment testing program shall be conducted on dredged material to determine whether the material is suitable for reuse. If sediment is not suitable for reuse, it would need to be transported to an acceptable disposal site.

Implementation Responsibility:  Project proponent/dredging contractor

Requirements and Timing:         Apply for and conform to DMMO permit

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance with dredge permit

Resulting Level of Significance. Mitigation Measure WATER-6 would reduce Impact WATER-6 to a less-than-significant level.

Vessel Operations and Fuel Spills. Vessel discharges of ballast water, bilge water, and sewage can impact water quality. Ballast water discharges are prohibited in San Francisco Bay. The Giulio Verne would not discharge bilge, gray water, or sewage in the Bay.

Marine oil spills can result from leaks or breaks in vessel fueling equipment, vessel accidents, mechanical or structural failures, or human errors such as valves left open or misaligned. Vessel refueling and other operations involving the handling of potentially harmful products and materials are carried out under strict USACE and EPA regulations prohibiting water pollution. Existing regulations and codes treat large vessels similarly to major industrial facilities sited on land. They are recognized as potential "point specific" sources of water pollution. Detailed procedures and engineering requirements have been written into regulations to prohibit harmful spills and discharges.

NOAA's Hazardous Materials Response and Assessment Division and the Office of Response and Restoration have issued a fact sheet on small diesel spills, which are defined as those in the range of 500 to 5,000 gallons (www.response.restoration.noaa.gov). This would be the general range of potential spills from vessels to be utilized for cable laying in the Bay for the proposed Project (i.e., Giulio Verne, barges, and tugboats). Diesel fuel is a light, refined petroleum product with a relatively narrow boiling range, meaning that, when spilled on water, most of the oil evaporates or naturally disperses within a few days. According to the NOAA fact sheet, this is particularly true for small spills, even in cold water. Consequently, after a few days there is rarely any oil on the surface for oil spill responders to recover. After spilling on water, diesel oil spreads very quickly to a thin film. Even when the oil is described as a heavy sheen, it is 0.0004 inch thick and contains about 1,000 gallons per square nautical mile of continuous coverage. Diesel has a very low viscosity and is readily dispersed into the water column when winds reach 5 to 7 knots.

Diesel oil is much lighter than water (its specific gravity is about 0.85, compared to 1.03 for seawater). It is not possible for this oil to sink and accumulate on the seafloor as pooled or free oil. However, it is possible for the oil to be physically mixed into the water column by wave action, forming small droplets that are carried and kept in suspension by the currents. Oil dispersed in the water column can adhere to fine-grained suspended sediments, which would eventually settle on the Estuary bottom. However, this process is not likely to result in measurable sediment contamination from small spills.

Diesel oil is not very sticky or viscous, compared to black oils. When small spills strand on the shoreline, the oil tends to penetrate porous sediments quickly, but also tends to be washed off quickly by waves and tidal flushing. Shoreline cleanup is usually not needed. Diesel oil is readily and completely degraded by naturally occurring microbes in 1 to 2 months.

Diesel is considered to be one of the most acutely toxic oil types. Fish, invertebrates, and seaweed that come in direct contact with a diesel spill may be killed. However, according to the NOAA fact sheet, small spills in open water are so rapidly diluted that fish kills have never been reported. Fish kills have been reported for small spills in confined, shallow water. Crabs and shellfish can be tainted from small diesel spills in shallow, nearshore areas. Small diesel spills can affect marine birds by direct contact, though the number of birds affected is usually small because of the short time the oil is on the water surface. Mortality is caused by ingestion during preening as well as hypothermia from matted feathers. According to NOAA's experience with small diesel spills, few birds are directly affected. However, small spills could result in serious impacts to birds under worst-case conditions, such as grounding of a vessel next to a large nesting colony or transport of diesel sheens into areas of high bird concentrations.

Accidental spills only account for a small fraction, up to 10 percent, of the total fuel contamination of waters. As much as 90 percent of oil in marine waters is from chronic sources that are difficult to identify, such as urban runoff, small craft boating, and improper disposal of used oil products (CDFG, 2002). Since 1991, when the California Oil Spill Prevention and Response Act and the Federal Oil Pollution Act of 1990 (OPA) took effect, there has been an 86 percent drop in the volume of oil spilled from oil tankers and barges in the United States. (It is important to note, however, that not all spills are necessarily reported.)

The primary mission of the Marine Environmental Protection (MEP) Division of the USCG San Francisco Marine Safety Officer (MSO) is emergency response to pollution incidents. This includes containment and cleanup of oil discharges and hazardous substances introduced into the navigable waters of the United States. The MSO coordinates response efforts with other agencies (federal, state, and local) in a joint effort to minimize damage to the environment caused by pollutants.

MEP Division personnel are trained in Incident Command System procedures and carry the qualifications of pollution investigators and Federal On-scene Coordinators. Actual removal is primarily done by qualified clean-up contractors and supervised by MSO personnel on scene.

The MEP Division is also involved in preparedness planning. The OPA mandated that Area Contingency Plans (ACPs) be created to respond to large oil spill incidents. Three ACPs are maintained by the San Francisco MSO: California North Coast, San Francisco Bay and Delta, and Central Coast.

Several Oil Spill Removal Organizations (OSROs) operate in the Bay and collaborate with the USCG, California Office of Spill Prevention and Response (OSPR), and other organizations in the Unified Command System during drills and spill responses. Response is available to OSRO members, or through the USCG or OSPR for orphan spills. Spill cleanup costs are paid by the party accepting responsibility for the spill. Spills occurring within the Bay can be attended to within 1 hour or less.

Impact WATER-7: Water Quality Impacts from Vessel Fuel Spills. Water quality degradation from vessel fuel spills would likely not be significant in light of its low probability and the past record. However, a potentially significant spill could still occur. This event would constitute a potentially significant impact.

Mitigation Measure WATER-7: Vessel Fuel Spill Response Plan. All vessel operators associated with the proposed Project shall update their contingency plans and continue to use emergency response services for pollution incidents. Review of updates and modifications to plans shall be done under the USCG's regular oversight of oil spill contingency plans. The work of updating and expanding the spill response plans shall be based on NOAA's Environmental Sensitivity Index (ESI), which involves the systematic compilation in a standardized format of information related to coastal shoreline sensitivity, biological resources, and human uses.

Implementation Responsibility:  Project proponent/vessel operator

Requirements and Timing:         Oil Spill Response Plan shall be completed in accordance with USCG guidance and submitted to the USCG, California OSPR prior to commencement of cable laying operations

Monitoring Requirements:          City of Pittsburg to monitor and ensure compliance. The USCG-OSPR may also monitor compliance

Resulting Level of Significance. Mitigation Measure WATER-7 would reduce Impact WATER-7 to a less-than-significant level.

4.4.3.4.2    Operations-related Impacts. No water quality impacts from operation of the offshore cable have been identified. Refer to Section 4.6, Marine Biological Resources, and Appendix F for a discussion of potential minor temperature increases in Bay sediments associated with offshore, buried DC and AC cable operation.

4.4.4    References

CDFG (California Department of Fish and Game). 2002. Spill Prevention and Response website: http://www.dfg.ca.gov/Ospr/spills.html.

CDWR (California Department of Water Recourses). 2003. California's Groundwater Bulletin 118. http://www.groundwater.water.ca.gov.

Cheng, R.T., V. Casulli, and J. W. Gartner. 1993. Tidal Residual Intertidal Mudflat (TRIM) Model and its Applications to San Francisco Bay, California. Estuarine, Coastal, and Shelf Science 369: 235-280.

City of Pittsburg. 2001. Pittsburg 2020: A Vision for the 21st Century City of Pittsburg General Plan Draft Environmental Impact Report. City of Pittsburg, Contra Costa County. January.

Geomatrix. 2000. Report of Results. Additional Site Characterization. Potrero Power Plant Site. Prepared for PG&E. April.

McKee, L., N Ganju, D. Schoellhamer, J. Davis, D. Yee, J. Leatherbarrow and R. Hoeniche. 2002. Estimates of Suspended-Sediment Flux Entering San Francisco Bay from the Sacramento and San Joaquin Delta. Website: http://www.sfei.org/watersheds/reports/
Delta_sediment_loads/MallardIssedimentloads.pdf.

Ritter, J.R. and W.R. Dupre. 1972. Maps Showing Areas of Potential Inundation by Tsunamis in the San Francisco Bay Region, California, U.S. Geological Survey, Miscellaneous Field Studies Map MF-480, 1:125,000.

RWQCB (Regional Water Quality Control Board). 1999. Bay Protection and Toxic Cleanup Program. Final Regional Toxic Hot Spot Cleanup Plan. March.

     2000. Beneficial Reuse of Dredged Materials: Sediment Screening and Testing Guidelines. Draft Staff Report.

     2005. Water Quality Control Plan – San Francisco Bay Basin (Region 2).

SFEC (San Francisco Energy Company). 1994. Application For Certification. October 1994.

SFEI (San Francisco Estuary Institute). 1994. 1993 Annual Report. Regional Monitoring Program for Trace Substances. Richmond, CA.

     2005a. The Pulse of the Estuary: Monitoring and Managing Water Quality in the San Francisco Estuary. SFEI Contribution 411. San Francisco Estuary Institute, Oakland, CA.

     2005b. 2003 Annual Monitoring Results. The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP). San Francisco Estuary Institute, Oakland, CA.

     2005c. Sediment, Water, and Bivalve Bioaccumulation Data from 1993-2004. The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP). San Francisco Estuary Institute, Oakland, CA. http://www.sfei.org/rmp/rmp_data_access.
html.

SFEP (San Francisco Estuary Project). 1999. State of the Estuary: A Report on Conditions and Problems in the San Francisco Bay/Sacramento-San Joaquin Delta.

SFPUC (San Francisco Public Utilities Commission). 2005. SFPUC Website <http://sfwater.org/main.cfm/MSC_ID/14>. Accessed 11/30/05.

SWRCB (State Water Resources Control Board). 1997. National Pollutant Discharge Elimination System (NPDES) General Permit No. CAS000001 (General Permit) Water Quality Order No. 97-03-DWQ Waste Discharge Requirements (WDRs) for Discharge of Storm Water Associated with Industrial Activities Excluding Construction Activities.

     1999. National Pollutant Discharge Elimination System (NPDES) General Permit No. CAS000002 for Storm Water Discharges Associated with Construction Activity (General Permit) Water Quality Order 99-08-DWQ.

Uncles, R.J. and D.H. Peterson. 1995. A Microcomputer Model of Long-term Salinity in San Francisco Bay, Environment International, in press U.S. Geological Survey, 1994, Water Resources Data California Water Year 1993 Volume 2. Pacific Slope Basins from Arroyo Grande to Oregon State Line Except Central Valley: U.S. Geological Survey Water-Data Report CA-93-2, Sacramento CA. 391 p.

URS. 2001. Final Offshore Sediment Characterization Report Potrero Power Plant. Prepared for Mirant California, LLC. May 18.

URS/Dames & Moore. 2000. Draft Initial Findings Report Offshore Sediment Sampling Potrero Power Plant. Prepared for Southern Company. September 28.

USACE (U.S. Army Corps of Engineers). 1984. San Francisco Bay Tidal Stage vs. Frequency Study. October.

     1998. San Francisco Bay to Stockton Phase III (John F. Baldwin) Navigation Channel Project Final Environmental Impact Report/Environmental Impact Statement. September.

USEPA and USACE. 1991. Evaluation of Dredged Material Proposed for Ocean Disposal – Testing Manual, (also known as the Green Book).

     1998. Evaluation of Dredged Material for Discharge in Inland and Near Coastal Waters – Testing Manual (also called Inland Testing Manual or ITM).

Walters, R.A., Cheng, R.T., and T.J. Conomos. 1985. Time Scales of Circulation and Mixing Processes of San Francisco Bay Waters: In: Temporal Dynamics of an Estuary: San Francisco Bay (eds, J.E. Cloern and F.H. Nichols). Developments in Hydrobiology, Dr. W. Junk Publishers, 13-36.

Wolfenden, J.D. and M.P. Carlin. 1992. Sediment Screening Criteria and Testing Requirements for Wetland Creation and Upland Beneficial Reuse. California Environmental Protection Agency and California Regional Water Quality Control Board.