| SECTION 4.0 | ENVIRONMENTAL SETTING, IMPACTS, AND MITIGATION |
| PROPOSED PROJECT |
The following section describes the terrestrial biological resources and natural communities occurring within the Project area, outlines potential impacts to biological resources that may result from the proposed Project, and presents mitigation measures to reduce impacts. This evaluation of biological resources includes a review of potentially occurring special-status species, wildlife habitats, vegetation communities, jurisdictional waters of the U.S., and waters of the State of California. This assessment is based upon field reconnaissance, literature searches, and data base queries. Marine biological resources are described in Section 4.6, Marine Biological Resources.
Biological site reconnaissance were conducted in April, September, and October of 2005. The proposed San Francisco HWC Converter Station site and the Pittsburg Standard Oil Converter Station site both consist of previously disturbed and developed industrial sites, including the proposed and alternative construction laydown areas. The biological site reconnaissance were supplemented with review of high-resolution digital aerial photography and topographic maps.
The sources of reference data reviewed for this assessment included the following:
This section provides a review—followed by specific descriptions—of the natural communities/vegetation types, soils, and associated wildlife that occur in the proposed Project area. Also included in this section is a review of the special-status species either known or with potential to occur in the Project area. The onshore Project sites are located within the City of San Francisco, the City of Pittsburg, and unincorporated Contra Costa County. Areas with natural vegetation and wetlands are most prevalent along the onshore cable routes associated with the Pittsburg Standard Oil Converter Station site. Native plants are uncommon elsewhere in the Project area and are generally limited to the ditches, sloughs, and marshes bordering the proposed cable alignment and access road in Pittsburg and converter station locations. The lack of native vegetation is likely the result of a history of industrial development, and other disturbance. A list of vascular plants identified at the Project sites is included in Appendix F.
4.5.1.1 Regional Setting
The Project area is located in the central coastal region of California within the Sacramento and San Joaquin River Delta, the Suisun Bay, San Francisco Bay, and the San Francisco Peninsula. The San Francisco Bay Area is a heavily urbanized and developed region. The landscape is composed of rolling hills, broad alluvial valleys, the Delta, and San Francisco Bay. The climate in San Francisco is coastal and moderate, with yearly rainfall averaging 19.6 inches. Average summer temperatures range between 54 and 73 degrees Fahrenheit (˚F), while average winter temperatures range between 41˚F and 56˚F. The eastern portion of the Project area in Contra Costa County exhibits more seasonality, with average summer temperatures ranging between 56˚F and 91˚F, and average winter temperatures ranging between 35˚F and 55˚F. The average yearly rainfall levels for the Pittsburg area is approximately 12.9 inches (Worldclimate, 2005).
4.5.1.2 Project Area Setting
4.5.1.2.1 San Francisco HWC Converter Station. San Francisco is located on the peninsula of land extending northward into the mouth of San Francisco Bay along the central coast of California. Historically, San Francisco County supported extensive native grasslands intermixed with a variety of vegetative communities, including oak woodland, salt marsh wetlands, coastal scrub, and riparian woodland. Intensive urban and industrial development has resulted in large losses and conversion of these habitats. The remaining native vegetative communities exist now as isolated remnant patches within urban, agricultural, and industrial landscapes, or in areas where varied topography has made disturbance difficult. The project area for the San Francisco HWC Converter Station site includes Township 2 South, Range 5 West, in an undefined southeastern section of the San Francisco North 7.5-minute USGS Quadrangle with elevations ranging from 0 to 25 feet above mean sea level (Map A.2-1, Sheet 1 of 10, in Appendix A of this EIR). These locations correspond to the eastern shoreline of the San Francisco Peninsula just south of Potrero Point and east of Potrero Hill and the shoreline at Pier 94/96. This area is currently composed of developed and industrial lands.
4.5.1.2.2 Pittsburg Standard Oil Converter Station. The Project area for the Pittsburg Standard Oil Converter Station site includes Township 2 North, Range 1 East, southwestern sections of the Antioch North 7.5-minute USGS Quadrangle with elevations ranging from 0 to 35 feet above mean sea level (see Sheet 10 of Map A.2-1). The proposed onshore DC/AC cable routes correspond to the edge of New York Slough near Winter Island, Arcy Lane adjacent to the Dow Chemical property, areas adjacent to portions of the Burlington Northern Santa Fe (BNSF) Railroad right-of-way (ROW) adjacent to the Dow Chemical property then south-southwest at a diagonal across Kirker Creek, an open grassland and wetlands to the northeast corner of the 7.5-acre Standard Oil site (refer to Map A.2-1, Sheet 10 of 10).
The Project area also includes an approximately 7-acre proposed construction laydown area located in an old drained constructed industrial pond bed located just north of the converter station site. The proposed laydown area currently includes annual grassland and some coyote brush (Baccaris pilularis) shrubs, with a red willow (Salix laevigata) and bulrush (Scirpus sp.) wetland in the northeastern corner. An alternative laydown area is located in a previously disturbed industrial area at the Delta Energy Center immediately south of the existing electrical power plant. The Pittsburg Standard Oil Converter Station site includes an existing access road from Loveridge Road.
The proposed Project site also includes a proposed access road, which would connect the converter station site with the Pittsburg-Antioch Highway. Construction of this access road would require construction of a bridge running from south to north from the Pittsburg-Antioch Highway across Kirker Creek. Kirker Creek has an ordinary high water mark (OHWM) that is approximately 12 feet wide at this crossing location and the remainder of the road would be constructed in a previously graded existing dirt road that runs north to the converter station site, past an abandoned baseball field. The area proposed for construction of the new access road had no vegetation at the time of the survey and consisted of graded dirt and fill. This area includes natural communities, such as annual grassland, salt marsh wetland, brackish wetland and seasonal wetlands, as well as previously disturbed and/or developed property.
4.5.1.2.3 Soils.
San Francisco HWC Converter Station. Soils at the San Francisco HWC Converter Station site are composed largely of fill materials. The soils along the proposed cable route near Potrero Point in the City of San Francisco consist of Urban land and Orthents, reclaimed complex. The urban lands are covered by asphalt, concrete, and buildings and other structures while the Orthents are recent developing soils composed from a mixture of soil, gravel, cement, Bay mud, and solid waste material (USDA-SCS, 1991). These soils are not listed as hydric soils.
Pittsburg Standard Oil Converter Station. Pittsburg Standard Oil Converter Station site soils are typically poorly drained and dominated by deep alluvium from the historical floodplains of the San Joaquin River and Kirker Creek. The soils along the Pittsburg proposed cable route between the converter station site and New York Slough include Clear Lake clay, Omni silty clay, Joice muck, and Rincon clay loam. Clear Lake clay, Omni silty clay, and Joice muck are all poorly drained alluvium soils associated with salt marsh, brackish marsh, and other wetlands and uplands in the Project area (USDA-SCS, 1980). These three soil types are listed as hydric soils in the region (USDA-SCS, 1995). The proposed DC/AC cable routes between the Standard Oil site and New York Slough traverse areas that have been previously disturbed, including existing roadways.
Plant communities are assemblages of plant species that occur together in the same area, which are defined by species composition and relative abundance. The plant communities were classified using A Manual of California Vegetation (Sawyer and Keeler-Wolf, 1995 and updated list from CDFG, 2003). Detailed descriptions of the plant communities occurring in and around the Project area and their general locations along the proposed and alternative on-shore cable routes are included in Appendix F. The plant communities described below generally correlate with wildlife habitat types. Plant communities considered rare and worthy of consideration by the CDFG are designated with an asterisk. The wildlife habitats identified in this section were described using CDFG's A Guide to Wildlife Habitats of California (Zeiner, 1988).
The nine primary plant community or habitat types in the Project area, including both the San Francisco and Pittsburg sites, are listed below:
4.5.1.4 Local Environmental Setting
The setting for the offshore cable route is discussed in Section 4.6, Marine Biological Resources. The local environmental settings for the converter station sites, including ancillary facilities, are described below.
4.5.1.4.1 San Francisco HWC Converter Station. This portion of the Project area includes previously developed and industrialized landscapes characterized above as Disturbed/Developed habitats. Any remnant vegetation included in these areas is dominated by landscaped, ruderal, and non-native species.
The proposed laydown area (Western Pacific site) and the alternative laydown area at Pier 94/96 and onshore cable route to the existing PG&E Potrero Substation include previously developed and industrialized landscapes described above as Disturbed/Developed habitats. Any remnant vegetation included in these areas is dominated by landscaped, ruderal, and non-native species. These areas are located on fill soils.
4.5.1.4.2 Pittsburg Standard Oil Converter Station. The proposed DC/AC cable route between the Standard Oil site and New York Slough comes onshore at Arcy Lane, an existing dirt access road near Dowest Slough and the Dow Chemical property. This road is adjacent to pickleweed and other salt marsh communities to the east. The cable would be routed from a splice box approximately 200 feet from the shoreline. The cables would be placed in and above the roadway and would travel down Arcy Lane, cross the BNSF ROW and then turn west on a paved road on the Delta Energy Center property before crossing under Kirker Creek (via horizontal directional drill) diagonally to the northeastern corner of the converter station site. Underground directional boring techniques would be implemented from the west end of the paved road at the Delta Energy Center to the northeast corner of the converter station site in order to avoid wetland and stream habitats associated with Kirker Creek.
In addition, the proposed site would include an access road running north from the Pittsburg-Antioch Highway to the Project site. This road would include construction of a bridge across Kirker Creek, an intermittent drainage, immediately adjacent to the Pittsburg-Antioch Highway. A substantial number and diversity of natural communities occurs adjacent to and within this portion of the Project area. These communities include Bulrush Series, Cattail Series, California Annual Grassland Series, Disturbed/Developed lands, Northern Claypan Vernal Pool Series, Pickleweed Series, Red Willow Series, Saltgrass Series, and Salt and Brackish Open Water and Creeks, including Kirker Creek. These communities are described in more detail in Appendix F.
Special-status plant and animal species are those that are recognized as rare and vulnerable to habitat loss or population decline. Some of these species receive specific protection as defined in federal or state endangered species legislation. Others have been designated as "sensitive" on the basis of adopted policies and expertise of state resource agencies or other organizations with acknowledged expertise, or policies adopted by local governmental agencies such as counties, cities, and special districts, to meet local conservation objectives. These species are referred to collectively as "special-status species" in this EIR. The various categories encompassed by the term, and the legal status of each, are summarized in Section 4.5.2, Regulatory Setting.
4.5.1.5.1 Special-status Species Within the Project Area. A list of special-status plant and animal species reported to occur within or in the vicinity of the Project area was compiled using data in the CNDDB consultation with the CDFG and United States Fish and Wildlife Service (USFWS), and a review of the CNPS online sixth inventory of rare plants (CDFG, 2005; CNPS, 2005, USFWS, 2005). These species and their potential to be impacted by the Project are summarized in a table included in Appendix F of this report. The table indicates each species' potential to occur in suitable habitat that is located in the immediate vicinity of the Project. Of the special-status plants and animals listed in the table, 10 wildlife species and nine plants have a medium or higher potential to occur within portions of the Project area. The "Potential for Impact" determination is made based on locations of known occurrences of the species, the presence of preferred habitats, and the potential for Project activities to affect a species or associated habitats. Species that may be impacted by the proposed Project (and are therefore addressed in detail in this document) are in bold type.
4.5.2.1 Federal
4.5.2.1.1 Federal Endangered Species Act. Under the Federal Endangered Species Act (FESA), the Secretary of the Interior and the Secretary of Commerce jointly have the authority to list a species as threatened or endangered (16 USC 1533[c]). Pursuant to the requirements of FESA, an agency reviewing a proposed project within its jurisdiction must determine whether any federally listed threatened or endangered species could be present in the project area and determine whether the proposed project would have a potentially significant impact on such species. In addition, the agency is required to determine whether the project is likely to jeopardize the continued existence of any species proposed to be listed under FESA or result in the destruction or adverse modification of critical habitat proposed to be designated for such species (16 USC 1536[3], [4]).
The USFWS also publishes a list of candidate species. Species on this list receive "special attention" from federal agencies during environmental review, although they are not protected otherwise under the FESA. The candidate species are taxa for which the USFWS has sufficient biological information to support a proposal to list as endangered or threatened.
4.5.2.1.2 Regulation of Activities in Waters of the United States. The U.S. Army Corps of Engineers (USACE) has primary federal responsibility for administering regulations that concern "waters of the U.S." within the Project area. The USACE acts under two statutory authorities: the Rivers and Harbors Act (Sections 9 and 10), which governs specified activities in "Navigable Waters of the U.S.;" and the Clean Water Act (Section 404), which governs specified activities in "other waters of the United States" including wetlands. The USACE requires that a permit be obtained if a project proposes placing structures within, over, or under navigable waters and/or discharging dredged or fill material into "waters of the U.S." below the ordinary high-water mark in non-tidal waters. The Environmental Protection Agency (EPA), USFWS, the National Marine Fisheries Services (NMFS), and several other agencies provide comment on USACE permit applications.
Wetlands are ecologically complex habitats that support a variety of both plant and animal life. In a jurisdictional sense, the federal government defines wetlands in Section 404 of the Clean Water Act as "areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support (and do support, under normal circumstances) a prevalence of vegetation typically adapted for life in saturated soil conditions" (33 Code of Federal Regulations [CFR] 328.3[b] and 40 CFR 230.3). The federal definition of wetlands requires three wetland identification parameters to be present: wetland hydrology, hydric soils, and hydrophytic vegetation. Examples of wetlands include freshwater marsh, seasonal wetlands, and vernal pool complexes that have a hydrologic link to other waters of the U.S. (see definition below for "other waters of the U.S."). The USACE is the responsible agency for regulating wetlands under Section 404 of the Clean Water Act, while the EPA has overall responsibility for the Act. The USACE has the option to issue a permit on a case-by-case basis (individual permit) or at a program level (general permit). Nationwide permits (NWPs) are an example of general permits; they cover specific activities that generally have minimal environmental effects. Activities covered under a particular NWP must fulfill several general and specific conditions, as defined by the NWP. If a proposed Project cannot meet these conditions, an individual permit may be required.
"Other waters of the U.S." refers to those hydric features that are regulated by the Clean Water Act but are not wetlands (33 CFR 328.4). To be considered jurisdictional, these features must exhibit a defined bed and bank and an ordinary high-water mark. Examples of other waters of the U.S. include rivers, creeks, intermittent and ephemeral channels, ponds, and lakes. Wet areas that are not regulated under the Clean Water Act would include stock watering ponds, agricultural ditches created in upland areas, and isolated wetlands that do not have a hydrologic link to other waters of the U.S., either through surface or subsurface flow. The discharge of fill into a jurisdictional feature requires a permit from the Corps.
4.5.2.2 State Regulation
The state's authority to regulate activities in "waters of the U.S." resides primarily with the CDFG and the State Water Resources Control Board (SWRCB). CDFG provides comment on USACE permit actions under the Fish and Wildlife Coordination Act. CDFG is also authorized under the California Fish and Game Code, Sections 1600-1607 to develop mitigation measures and enter into Streambed Alteration Agreements with applicants who propose projects that would obstruct the flow of, or alter the bed, channel, or bank of a river or stream in which there is a fish or wildlife resource, including intermittent and ephemeral streams. The SWRCB, acting through the appropriate Regional Water Quality Control Board (RWQCB), must certify that an USACE permit action meets state water quality objectives (Section 401, Clean Water Act).
California Fish and Game Code Sections 1600-1607 require the notification of CDFG for any activity that could affect the bank or bed of any stream that has value to fish and wildlife. Upon notification, the CDFG has the responsibility to prepare a Streambed Alteration Agreement, in consultation with the project proponent.
4.5.2.2.1 California Endangered Species Act. Under the California Endangered Species Act (CESA), CDFG has the responsibility for maintaining a list of threatened species and endangered species (California Fish and Game Code 2070). The CDFG also maintains a list of "candidate species" which are species that the CDFG has formally noticed as being under review for addition to either the list of endangered species or the list of threatened species. The CDFG also maintains lists of "species of special concern" which serve as "watch lists." Pursuant to the requirements of CESA, an agency reviewing a proposed project within its jurisdiction must determine whether any state-listed endangered or threatened species could be present in the project area and determine whether the proposed Project would have a potentially significant impact on such species. In addition, the CDFG encourages informal consultation on any proposed project that could impact a candidate species.
California Environmental Quality Act (CEQA) Guidelines Section 15380 provides protection to both currently listed rare or endangered species and those that may soon become rare or endangered in order to determine whether a project could have a significant effect on, for example, a "candidate species" that has not yet been listed by either the USFWS or CDFG.
4.5.2.3 Other Statutes, Codes, and Policies Affording Limited Species Protection
4.5.2.3.1 The Migratory Bird Treaty Act. The Migratory Bird Treaty Act (16 USC, Sec. 703, Supp. I, 1989) prohibits killing, possessing, or trading in migratory birds except in accordance with regulations prescribed by the Secretary of the Interior. This act encompasses whole birds, parts of birds, bird nests, and eggs. Birds of prey are protected in California under the State Fish and Game Code (Section 3503.5, 1992). Section 3503.5 states that it is "unlawful to take, possess, or destroy any birds in the order Falconiformes or Strigiformes (birds of prey) or to take, possess, or destroy the nest or eggs of any such bird except as otherwise provided by this code or any regulation adopted. Construction disturbance during the breeding season could result in the incidental loss of fertile eggs or nestlings, or otherwise lead to nest abandonment. Disturbance that causes nest abandonment and/or loss of reproductive effort is considered "taking" by the CDFG.
4.5.2.3.2 Rare or Endangered Species. Although threatened and endangered species are protected by specific federal and state statutes, CEQA Guidelines Section 15380 provides that a species not listed on the federal or state list of protected species may be considered rare or endangered if the species can be shown to meet certain specified criteria. These criteria have been modeled after the definition in FESA and the section of the California Fish and Game Code dealing with rare or endangered plants or animals.
As such, vascular plants listed as rare or endangered by the CNPS (CNPS, 2001), but which have no designated status or protection under federal or state endangered species legislation, are defined as follows:
4.5.3.1 Thresholds of Significance
CEQA Guidelines Section 15206 specifies that a project shall be deemed to be of statewide, regional, or area-wide significance if it would substantially affect sensitive wildlife habitats including, but not limited to, riparian lands, wetlands, bays, estuaries, marshes, and habitats for rare and endangered species as defined by State Fish and Game Code Section 903.
CEQA Guidelines (Appendix G) state that the project would have a significant effect on the environment if it would:
CEQA Guidelines Section 15380 further provides that a plant or animal species may be treated as "rare or endangered" even if not on one of the official lists if, for example, it is likely to become endangered in the foreseeable future.
The discussions below for the proposed Project provide an assessment of potential impacts and determinations of significance based on consideration of Section 15380 of the CEQA Guidelines, the policies and regulations governing biological resources of the project area, and the project actions.
4.5.3.2 San Francisco HWC Converter Station
4.5.3.2.1 Construction-related Impacts. The San Francisco HWC Converter Station site and ancillary facilities are Disturbed/Developed properties in industrial/commercial areas on artificial fill soils. No significant impacts to onshore natural communities, wildlife habitat, wetlands or special-status species are expected from construction or operations of the proposed Project at this site.
4.5.3.2.2 Operations-related Impacts. No impacts to terrestrial biological resources are expected from operation of the San Francisco HWC Converter Station.
4.5.3.3 Pittsburg Standard Oil Converter Station
4.5.3.3.1 Construction-related Impacts. Construction of the Pittsburg Standard Oil Converter Station, including onshore cable route and project facilities, proposed access road, bridge construction and use of construction laydown areas, has the potential to impact wetlands and waters of the United States as well as special-status species and the habitats that support them.
Potential Impacts to Natural Communities and Wildlife Habitat. Continued loss of undeveloped and cultivated open space in and around the City of Pittsburg over the last decade has significantly increased the need to preserve existing wildlife habitats and open areas. The regional approach to this issue has resulted in the creation of the East Contra Costa Habitat Conservation Plan and Natural Communities Conservation Plan (HCP/NCCP) (Contra Costa County, 2005), which has not yet been implemented. This draft plan will likely be implemented and active by June or July 2006 (John Kopchik, 2005). However, an informal process is currently available through the USFWS and CDFG to purchase credits and obtain species-take coverage before formal implementation is complete.
Portions of the Pittsburg Standard Oil Converter Station onshore cable route contain wetlands, and potential special-status species habitat. Additionally, known extant populations of special-status species occur adjacent to the proposed onshore cable route near Arcy Lane (Delta Diablo Sanitation District outflow access road). In order to avoid and/or minimize impacts to these species and communities to the greatest extent possible, the DC cable would be trenched into an existing roadway, Arcy Lane, while the AC line would be routed aboveground on poles over the roadway. Additionally, since vernal pool crustaceans are known to be present near the Pittsburg Standard Oil Converter Station onshore cable route, impacts to all vernal pools and depressions ponding seasonal water (seasonal pools) would be avoided by keeping cable construction and trenching within existing roadways and previously developed lands within the Project area.
Upland Communities.
California Annual Grassland Series. Portions of the grasslands associated with the Pittsburg Standard Oil Converter Station onshore cable route have the potential to be impacted by trenching and equipment during construction. Though this plant community is dominated by non-native species and is regionally abundant, the impacts to this community would represent a temporary incremental loss of potential foraging and nesting habitat for numerous birds, reptiles, and small mammals and a potential temporary reduction in prey for predatory mammals, birds and reptiles. Due to the fact that the majority of the cable route follows an existing roadway and other paved or previously developed properties, this impact is considered less than significant.
Wetland Communities.
Northern Claypan Vernal Pool Series. The proposed Project has the potential to directly and indirectly impact this community. Indirect impacts are often considered by the USFWS as any ground-disturbing activities within 250 feet of the hydrologic edge of a pool. One natural vernal pool occurs immediately adjacent to the southern end of the Arcy Lane portion of the Pittsburg Standard Oil Converter Station cable route. As the USFWS often considers direct impacts as those that occur within 50 feet of the hydrologic edge of a pool, this Project would likely be considered by the USFWS to have a direct impact on this pool. The edge of the existing dirt roadway where trenching or construction would occur is approximately 5 feet from the edge of the pool at this location.
Vernal Pool Fairy Shrimp, Vernal Pool Tadpole Shrimp, California Linderiella. The proposed Project may have potentially significant adverse impacts, either directly or through habitat modifications, to terrestrial endangered, rare, or threatened species, as listed in Title 14 of the California Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12). Where the route parallels the south side of the BNSF ROW within an existing paved access road, another long seasonal pool occurs within the railroad ROW adjacent to the southern side of the tracks less than 0.25 mile from the first pool. Populations of vernal pool fairy shrimp, a federally listed vernal pool crustacean, as well as California linderiella fairy shrimp, a federal species of concern, have recently been documented as occurring within the pool within the railroad ROW (CDFG, 2005). Other invertebrate species with potential to occur in these habitats include Ricksecker's water scavenger beetle (Hydrochara rickseckeri), curve-footed hygrotus diving beetle (Hygrotus curvipes), and vernal pool tadpole shrimp (Lepidurus packardi). This impact is considered potentially significant. Adults, larvae, or cysts may be incidentally harmed or harassed by construction activities within the Project area adjacent to these seasonally inundated habitats.
Impact TBIO-1: Trenching Near Pools Providing Habitat for Special-status Species. This is a potentially significant impact.
Mitigation Measure TBIO-1a: Avoidance and Prevention Measures for Work Near Vernal Pool Habitat. Cable construction along Arcy Lane shall be placed a minimum of 8 feet away from the vernal pool edge of the roadway and all construction activities shall maintain a 15-foot buffer to the hydrologic edge of the pool. The vernal pool edge of the roadway pool shall be fenced with a silt fence with hay bundles placed at the outside base of the fence to avoid impacts to this wetland. All construction personnel, work crews, and project staff shall be restricted from entering the vernal pool areas, staging equipment or depositing any waste disposal soils, littering in or otherwise in any way entering these sensitive habitats. Due to the fact that this portion of the Project area is relatively flat, significant erosion or soil movement is not expected from trenching activities within the adjacent roadway.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: At least one week (seven days) prior to construction a contractor shall install the silt fence and other preventive measures specified; during construction a biological monitor shall ensure compliance with the 15-foot buffer to the hydrological edge of the pool.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species. This includes staging, construction of the cable route, use of laydown areas and implementation of Horizontal Directional Drilling (HDD) or comparable technology or overhead techniques for crossing wetlands, stream channels, vegetated canals or ditches. Effectively this shall include a monitor being present during construction of the proposed Pittsburg Standard Oil Converter Station cable route, access road and laydown area.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-1b: Awareness Training for Workers. Prior to construction, all construction workers shall take part in a USFWS-approved worker environmental awareness program on vernal pool crustaceans given by a USFWS-approved biologist.
Implementation Responsibility: Project proponent
Requirements and Timing: All construction personnel shall receive training from a qualified biologist prior to beginning construction activities in the project area. The awareness program will be given at the start of construction and thereafter as required for new construction personnel.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species or their habitats. This monitor shall ensure the Mitigation Measure TBIO-1b is enforced.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-1c: Biological Monitoring Requirement. A USFWS-approved biologist shall be present on site during any construction activities adjacent to vernal pool crustacean habitat.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: The biological monitor shall provide status communications of Project activities to the lead agency and regulatory agencies.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-1a through TBIO-1c would reduce Impact TBIO-1 to a less-than-significant level.
Bulrush Series. Bulrush stands have the potential to be impacted within the northeast corner of the proposed construction laydown property for the Pittsburg Standard Oil Converter Station. This stand, within the Project area, totals less than 0.05 acre and Project impacts within this stand could be avoided through appropriate placement of the laydown area. This community is considered optimal habitat for California clapper rail (Rallus longirostris obsoletus) and California black rail (Laterallus jamaicensis coturniculus), as well as giant garter snake (Thamnophis gigas).
Cattail Series. The Project has the potential to directly impact this community. This community occurs in ditches and wetlands associated with Kirker Creek along the Pittsburg Standard Oil Converter Station onshore cable route. Dust and noise from heavy equipment use during construction activities adjacent to this community have the potential to discourage wildlife activity. Additionally, certain endangered wildlife such as giant garter snake that may forage in these wetlands have the potential to be impacted by habitat removal. This impact is considered potentially significant.
Pickleweed Series. Project impacts along the Pittsburg Standard Oil Converter Station cable route would largely occur adjacent to and outside of this community. This community is considered optimal habitat for species such as salt marsh harvest mouse and the species is known to occur adjacent to Arcy Lane near the Project area. This impact is considered potentially significant.
Salt Marsh Harvest Mouse. Impacts or take of this species could occur during trenching of at least one cable in 0.5 mile of existing dirt road at Arcy Lane immediately adjacent to pickleweed salt marsh known to support the species (CDFG, 2005).
Based on the habitats present in the Project area, the following additional special-status species may be impacted by the proposed Project.
California Clapper Rail, California Black Rail, Northern Harrier, Short-eared Owl, Salt Marsh Yellowthroat and White-Tailed Kite. These species of birds could potentially be impacted by trenching of the onshore cable route to the Pittsburg Standard Oil Converter Station site. The corridor contains potential foraging and nesting habitat for the above species. In the case of the northern harrier, white-tailed kite and short-eared owl potential nesting habitat would also be impacted through the construction of the laydown area and access road for the Pittsburg Standard Oil Converter Station site. These impacts are considered potentially significant.
Impact TBIO-2: Trenching Near Saltmarsh and Wetland Habitats (Pickleweed, Bulrush and Cattail). The proposed Project has the potential to significantly impact, either directly or through habitat modifications, terrestrial endangered, rare, or threatened species, as listed in Title 14 of the California Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12).
Mitigation Measure TBIO-2a: Marking Habitat and Implementing Physical Avoidance Measures. In order to protect wildlife habitat and prevent disturbance or take of salt marsh harvest mouse, black rail, or California clapper rail, a silt fence with hay bundles placed at the outside base of the fence shall be installed by a qualified biologist along the entire Arcy Lane portion (0.5 mile) of the proposed onshore cable route. All construction personnel, work crews, and project staff shall be restricted from crossing this fence at the edge of the dirt road, staging equipment or depositing any waste disposal soils, littering in or otherwise in any way entering these sensitive habitats. Due to the fact that this portion of the Project area is relatively flat, significant erosion or soil movement is not expected from trenching activities within the adjacent roadway. The fencing shall not be removed until all construction and clean-up activities were completed in the area.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: The silt fence and hay bundles shall be installed by a contractor at least 15 days prior to the initiation of any construction activities in this area. The silt fence and other barriers shall be monitored daily by the biological monitor and construction personnel during construction in order to identify, adjust, or repair the fence as needed to ensure the feature remains intact and functional.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-2b: Monitoring Requirements for Salt Marsh Species. In order to protect wildlife habitat and prevent disturbance or take of salt marsh harvest mouse, black rail, or California clapper rail, a qualified biological monitor familiar with the species shall be present during each day of construction and site preparation adjacent to these species potential habitats (i.e., salt marsh, grassland near salt marsh, pickleweed). As applicable, the biological monitor shall be authorized to require remedial protective measures in the field.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: A biological monitor familiar with these saltmarsh species, shall be present during all project related activities within the approximately 0.5 mile section of the onshore cable route from the splice box to the Delta Energy Center property.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-2c: Awareness Training for Construction Personnel. Prior to construction, all construction workers shall take part in a USFWS-approved worker environmental awareness program concerning these species given by a USFWS-approved biologist. The biological monitor shall train work crews in standard procedures for identifying and avoiding impacts to these species prior to the start of construction activities.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: All construction personnel shall receive training from a qualified biologist prior to beginning construction activities in the Project area. The awareness program will be given at the start of construction and thereafter as required for new construction personnel.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species or their habitats. This monitor shall ensure the Mitigation Measure TBIO-2c is enforced.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-2d: Halting Work to Remove Endangered Species from Job Site. If a salt marsh harvest mouse, black rail, or California clapper rail is observed in or near the Project area, all construction shall cease until the mouse or bird moves out of the project area or, in the case of salt marsh harvest mouse, is captured by a qualified biologist and removed from the Project area for relocation.
Implementation Responsibility: Project proponent/ construction contractor<
Requirements and Timing: All work in the Project area shall cease immediately when any of these species is observed by any employee or the biological monitor within the Project area.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species or their habitats. This monitor shall ensure the Mitigation Measure TBIO-2d is enforced.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-2e: Check Under Parked Vehicles. The area beneath vehicles or equipment parked in the Project area shall be checked for the presence of salt marsh harvest mouse before being moved, during construction in the roadway and staging activities within the entire Arcy Lane habitat unit. Vehicle speed limits in this area shall not exceed 10 miles per hour.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: This measure shall be implemented each time a vehicle or equipment that is parked in the Arcy Lane portion of the project area is moved.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species or their habitats. This monitor shall ensure the Mitigation Measure TBIO-2e is enforced.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-2f: Pre-construction Nesting Surveys. A qualified wildlife biologist shall perform pre-construction nesting surveys for all bird and raptor species within the Project area and immediate vicinity a maximum of 30 days before construction begins. If an active raptor nest is located, no activities shall occur within 0.25 mile of the nest until young are fledged and the nest is abandoned. If construction activities occur outside of the nesting period (nesting period is typically between February and August) no nesting surveys shall be required.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: Pre-construction nesting surveys shall be performed a maximum of 30 days prior to the beginning of construction activities.
A qualified biological monitor shall be required to be present during all Project-related activities that may impact special-status species or their habitats. This monitor shall ensure the Mitigation Measure TBIO-2f is enforced.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-2a through TBIO-2f would reduce Impact TBIO-2 to a less-than-significant level.
Impacts to Wetlands.
Red Willow Series. This community has the potential to be impacted from the proposed Project within the Pittsburg Standard Oil Converter Station proposed construction laydown site. This vegetation occurs adjacent to the BNSF ROW in the northeast corner of the proposed laydown area. Potential impacts to this wetland community could occur in the form of tree removal or alterations to wetland hydrology and habitat.
Saltgrass Series. This community has the potential to be impacted within the Pittsburg Standard Oil Converter Site onshore cable route. This vegetation occurs adjacent to the BNSF ROW on the both sides of the tracks. Wildlife use is similar to that of California annual grasslands, but wetland-associated wildlife is more likely to occur in these habitats. Due to the fact that the cable route follows an existing roadway and a previously disturbed railroad easement this impact is considered less than significant and would not require mitigation.
Perennial Emergent and Seasonal Wetlands. Impacts to seasonal wetland, perennial emergent wetlands and waters of the U.S. along the Standard Oil Pittsburg Converter Station onshore cable route could occur from project activities. Wetlands occur adjacent to and within significant portions of this route and are also associated with the reaches of Kirker Creek within the Project area (i.e., crossings). These activities have the potential to fill wetlands which may fall under the jurisdiction of USACE, and destroy habitat for special-status species. This impact is considered potentially significant.
Impact TBIO-3: Disturbance or Fill of Wetlands and Streams. Potential jurisdictional wetlands and streams exist in the project area that may be filled or altered during construction, due to project trenching for onshore cables associated with the Pittsburg Standard Oil Converter Station site. Other temporary and permanent impacts would occur from proposed bridge construction activities for the access road from the Pittsburg-Antioch Highway to the converter station site. Other wetlands occur in portions of proposed laydown area. This is a potentially significant impact.
Mitigation Measure TBIO-3a: Implement HDD or Comparable Technology Techniques to Avoid Impacts to Kirker Creek and Associated Floodplain Wetlands. As stated in the project description of this document (Section 3.0 and Appendix A), onshore cable route for the proposed site would incorporate HDD or comparable technology techniques from the west end of the paved road on the Delta Energy Center property all the way to the northeast corner of the Pittsburg Standard Oil Converter Station site. The HDD shall be drilled at a minimum of 15 feet below the bottom of the Kirker Creek streambed in order to avoid a "frac-out" (i.e., release of drilling mud). The temperatures associated with the buried AC cable are expected to be warmer than ambient soil temperatures over a limited area (refer to Appendix F for more information). The required minimum HDD depth shall also remove any potential for impacts to these wetlands or streams due to potential heating from the buried cable. Implementation of the HDD or comparable technology techniques will avoid impacts to wetlands and streams within this portion of the onshore cable route.
Implementation Responsibility: Project proponent/construction contractor.
Requirements and Timing: HDD operations shall be conducted as discussed above during the applicable portion of the construction phase.
Qualified biological monitors shall be required to be present during Project-related ground disturbance in this area.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-3b: Wetland and Jurisdictional Waters Delineation Survey. Prior to construction, the Applicant shall hire a qualified wetland delineator (i.e., biologist) familiar with the wetland types in the east Bay Area to survey the proposed onshore cable route, laydown areas and other portions of the Project area. The biologist shall mark the outer upland edges of potential wetlands and streams in the Project area and oversee installation of silt fences around the edges of these features in order to avoid Project impacts.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: The informal wetland and waters delineation, survey and marking and fencing of features to be avoided shall be conducted at least 15 days prior to initiation of construction activities within any portion of the project area.
Fenced and marked wetlands shall be monitored by a biological monitor weekly to ensure that wetland boundaries and fences remain intact.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-3c: Wetland and Pool Avoidance. Wetlands and a seasonal pool, representing vernal pool crustacean habitat for endangered species, shall be avoided by all construction activities in order to avoid fill or alteration of wetlands and streams in the project area and to avoid impacts to sensitive species or their habitats. No trenching or equipment shall enter within a minimum of 15 feet from the edge of the target seasonal pool boundaries and areas of hydrologic influence. In addition, no construction personnel shall be allowed to enter or disturb the seasonal pool or vegetated habitat immediately surrounding it. A trained biological monitor shall be present during all trenching activities occurring adjacent to vernal pool wetlands in the Project area. If disturbance occurs in any such feature during Project construction then the biological monitor shall immediately notify the USFWS and inform them of potential "take" of these federally endangered species. Any impacts to these habitats shall be considered "take" of these species and will require agency consultation to develop appropriate mitigation measures.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: If any disturbance occurs to the vernal pool habitat or other sensitive wetland habitats identified within this report or occurring adjacent to the Project area, then the USFWS will be contacted immediately to initiate consultation and determine appropriate mitigation.
As noted in the mitigation measures above, a qualified biological monitor shall be required to be present during the full duration of all Project and Project-related activities. This includes staging, construction of the cable route, use of laydown areas and implementation of HDD or comparable technology techniques beneath wetlands and stream channels or vegetated canals or ditches. Effectively this would include a monitor being present during construction of the entire Standard Oil Converter Station cable route, access road and laydown area.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-3d: Obtain Streambed Alteration Agreement. Potential impacts or alteration of streambeds from bridge construction over and HDD or comparable technology drilling beneath Kirker Creek at two locations would require a Streambed Alteration Agreement (Section 1600-1616) through CDFG.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: Consultation with CDFG shall occur at least nine months prior to the start of construction.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-3a through TBIO-3d would reduce Impact TBIO-3 to a less-than-significant level.
Impacts to Potentially Occurring Special-status Species.
Wildlife. Salt marsh harvest mouse (Reithrodontomys raviventris) is known to occur in the salt marsh habitats adjacent to, and east of, Arcy Lane (near New York Slough). These areas also have the potential to support California black rail, and California clapper rail. Construction would occur in close proximity to these habitats, within the roadway of Arcy Lane. These habitats would be avoided by project activities if all construction equipment, personnel and activities remained in the existing roadway.
Western pond turtle (Actinemys marmorta pallida) has the potential to be impacted by placement of the cable route, access road and bridge construction near wetlands and Kirker Creek during construction of the onshore cable route and construction of facilities for the Standard Oil Pittsburg Converter Station.
Giant garter snake historically ranged throughout the Sacramento and San Joaquin valleys but is very scarce throughout its range due to the elimination of natural sloughs and marshy areas. This federally listed threatened species is an active diurnal snake rarely found away from water. It is likely to feed upon introduced species such as mosquito fish (Gambusia attinis), carp (Cyprinus carpio), and minnows (Family Cyprinidae), as native historic food sources are often unavailable. Potential habitat within the Project area is located within the open brackish marshes within portions of the Pittsburg Standard Oil Converter Station onshore cable route including bulrush, cattail and red willow wetlands. Vegetated and wetland habitats associated with Kirker Creek also represent potential habitat for this species.
Giant Garter Snake and Western Pond Turtle. The proposed Project may affect these species if they are present in the vegetated marshes and ditches adjacent to the Pittsburg Standard Oil Converter Station onshore cable route. These adjacent wetlands and ditches provide potential habitat for these species, because they contain a continuous water supply and sufficient emergent vegetation. Western pond turtles are known from the immediate vicinity of the Project area while giant garter snake is expected from the region in these habitat types. Snakes and turtles may be incidentally harmed or harassed by construction activities if they are foraging within the Project area adjacent to the marsh or streams. This is a potentially significant impact.
Impact TBIO-4: Potential Impacts to Giant Garter Snake and Western Pond Turtle. The proposed Project has the potential to significantly impact, either directly or through habitat modifications, terrestrial endangered, rare, or threatened species, as listed in Title 14 of the California Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12).
Mitigation Measure TBIO-4a: Avoidance of Habitat and Timing of Construction. No grading, excavating, or filling may take place in or within 50 feet of the marsh, wetland or stream edges within the Project area between October 1 and May 1 unless otherwise authorized by the USFWS and CDFG.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: No activity within 50 feet of the marsh, wetland or stream edges between October 1 and May 1, unless otherwise authorized by the USFWS and CDFG.
A qualified biological monitor shall be required to be present and ensure that the mitigation measure is enforced during all Project-related activities that may impact special-status species or their habitats.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-4b: Worker Training for Giant Garter Snake and Western Pond Turtle. Prior to construction, all construction workers shall take part in a Service-approved worker environmental awareness program given by a USFWS-approved biologist.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: Prior to initial start of work and thereafter as needed for new workers entering the Project area, all construction workers and employees shall receive training on avoidance and awareness of these species prior to the start of work in the Project area.
A qualified biological monitor shall be required to be present and ensure that the mitigation measure is enforced during all Project-related activities that may impact special-status species or their habitats.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-4c: Biological Monitoring for Giant Garter Snake and Western Pond Turtle. A USFWS-approved biologist shall be present on site during any construction activities within western pond turtle or giant garter snake habitat. If a giant garter snake or western pond turtle is found in the work area, all work shall cease until the snake or turtle leaves the work area. Monitoring and avoidance measures shall follow protocols established by the USFWS (see Appendix F for details).
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: A qualified biological monitor shall be required to be present and ensure that the mitigation measure is enforced during all Project-related activities that may impact special-status species or their habitats.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-4a through TBIO-4c would reduce Impact TBIO-4 to a less-than-significant level.
Special-status Birds and Raptors. Salt marsh yellowthroat (Geothlypis trichas sinuosa) occupies fresh and saltwater marshes with abundant vegetative cover, including bulrush, cattails and willows. These habitats occur adjacent to Arcy Lane and on either side of portions of the BNSF ROW.
Northern harrier (Circus cyaneus) inhabits areas of tall, dense grasses, moist or dry shrubs, and the edges of row crops for nesting, cover, and feeding. Common food items are voles, frogs, small reptiles, crustaceans, and insects. Nests are built on ground with shrubby vegetation. These birds could nest in grasslands or adjacent to marshes associated with the Project area.
Short-eared owl (Asio flammeus) hunts in open grasslands, dunes, fresh and saltwater marshes and other open country. The species nests on the ground in a grass-lined depression that is often concealed in weeds or beneath shrubs. The species typically hunts for small mammals during the late afternoon onwards through the night. This species is covered under the East Contra Costa County HCP (Contra Costa County, 2005). The project area contains open grassland and salt marshes that represent both nesting and foraging habitat for the species.
White-tailed kite (Elanus leucurus) inhabits areas of tall, dense grasses, shrubs, farmlands and open country. The species mainly feeds on rodents and insects. Nests are typically built in tall trees near a water source. These birds forage in grasslands and grain fields associated with the project area. Several individuals of this species were observed near the grassland berms around the perimeter of the Pittsburg Standard Oil Converter Station site during the survey, and foraging behavior was observed.
Northern Harrier, Short-eared Owl, Salt Marsh Yellowthroat and White-Tailed Kite. These species of birds may be impacted by use of this area for construction laydown. The area constitutes potential foraging and nesting habitat for the above species. In the case of the northern harrier, white-tailed kite, and short-eared owl, potential nesting habitat could also be impacted through the use of the construction laydown area. These impacts are considered to be potentially significant.
Impact TBIO-5: Potential Impacts to Special-status Raptors and Birds in Construction Laydown Area. The proposed Project has the potential to significantly impact, either directly or through habitat modifications, terrestrial endangered, rare, or threatened species, as listed in Title 14 of the California Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12).
Mitigation Measure TBIO-5: Pre-construction Nesting Surveys at Construction Laydown Area. A qualified wildlife biologist shall perform pre-construction nesting surveys for all bird and raptor species within the construction laydown area and immediate vicinity at least 30 days prior to start of construction. If an active raptor nest is located no activities will occur within 0.25 mile of the nest until young are fledged and the nest is abandoned. If construction activities occur outside of the nesting period (nesting period is typically between February and August), no nesting surveys would be required.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: Pre-construction nesting surveys for all bird and raptor species within the Project area and immediate vicinity shall be performed at least 30 days prior to start of construction.
A qualified biological monitor shall be required to be present and ensure that the mitigation measure is enforced during all Project-related activities that may impact special-status species.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measure TBIO-5 would reduce Impact TBIO-5 to a less-than-significant level.
Vernal Pool Invertebrates. Vernal pool invertebrates include: vernal pool fairy shrimp, California linderiella, vernal pool tadpole shrimp, Ricksecker's water scavenger beetle and the curve-footed hygrotus diving beetle. These species occur during the wet winter and spring months in vernal pools and seasonal freshwater wetlands. Vernal pool fairy shrimp and California linderiella fairy shrimp are known to occur in a long seasonal pool along the BNSF ROW west of Arcy Lane (CDFG, 2005). A large natural vernal pool also occurs at the southern end of Arcy Lane near the intersection with the BNSF ROW near the Pittsburg Standard Oil Converter Station onshore cable route. Due to the adjacency of these two pools, vernal pool crustaceans are likely to occur in the Arcy Lane pool. Impacts to these species are identified in TBIO-1 and Mitigation Measures TBIO-1a-1c.
Plants. Because initial plant surveys for this Project occurred outside the common blooming period, plants that may occur at the Project site may not have been observed. Mitigation Measures TBIO-6a and TBIO-7a ensure surveys for rare plants would be conducted in spring.
Alkali Milk-vetch (Astragalus tener var. tener). This diminutive herbaceous annual member of the pea family (Fabaceae) occurs on alkaline flats and in seasonally moist alkaline meadows at elevations typically below 200 feet. The species is rare and endemic to California. It is known to occur in the southern Sacramento Valley, northern San Joaquin Valley and the eastern San Francisco Bay Area. Twenty-three of the 35 known occurrences of this species have been extirpated (made locally extinct) by habitat destruction. The only protected population of this species occurs at the Jepson Prairie Preserve in Solano County. The seasonally saturated alkaline habitats in the eastern grassland portion of the Project area may provide habitat for this species.
Bent-flowered Fiddleneck (Amsinckia lunaris). This annual member of the forget-me-not family (Boraginaceae) occurs rarely in a broad range of coastal grassland and scrub habitats. The plants have golden yellow flowers in a coiled inflorescence and hairy herbage. This species has the potential to occur in less disturbed grasslands within the Project area, including portions of the BNSF ROW and grasslands adjacent to Arcy Lane.
Big Tarplant (Blepharizonia plumosa ssp. plumosa). This annual member of the sunflower family (Asteraceae) is known to occur in grasslands. The species is known in Contra Costa County and was previously documented within the area of the proposed access road from the Antioch-Pittsburg Highway to the Pittsburg Standard Oil Converter Station site. However this site currently has only a previously graded dirt road without vegetation. The species is also known to occur southwest of the project area on private lands. This species was not located during rare plant surveys conducted for the project that occurred within the species' bloom period. Only a broad polygon is depicted on the CNDDB map of the species previous occurrence near the proposed access road parcel, and this occurrence was last documented in 1916. Therefore, it is likely this population has been extirpated (i.e., made locally extinct). This species has the potential to occur in grasslands along the Pittsburg Standard Oil Converter Station site and access road.
Delta Mudwort (Limosella subulata). This perennial, herbaceous member of the figwort family (Scrophulariaceae) occurs in saltwater marshes and along shorelines. The species is known from the immediate Project vicinity along the shores and sloughs adjacent to New York Slough. Project activities in this area would occur within Arcy Lane, an existing road, and no habitat for this species occurs in this road.
Diamond-petaled Poppy (Eschscholzia rhombipetala). This species occurs very rarely on alkaline clay soils in open grasslands and fallow fields and is an annual member of the poppy family (Papaveraceae). The species is characterized by having a barrel shaped receptacle with no rim and small yellow petals (less than 1.5 centimeter). This species was presumed extinct until being rediscovered in 1992 on the Carrizo Plain. The occurrence from the Antioch Dunes, 2.3 miles east of the Project area, is considered extirpated.
Dwarf Downingia (Downingia pusilla). This annual member of the bellflower family (Campanulaceae) occurs rarely in vernal pools and roadside wetlands or ditches. Both of these wetland habitat types occur within and immediately adjacent to the project area. The flowers are low-growing and are blue to white with two small yellow spots near the throat.
Hoover's Cryptantha (Cryptantha hooveri). This annual member of the forget-me-not family occurs rarely in a broad range of coastal grassland habitats. The plants have white flowers in a coiled inflorescence and hairy herbage. This species has the potential to occur in less disturbed grasslands within the Project area, including grasslands adjacent to Arcy Lane.
Round-leaved Filaree (Erodium macrophyllum). This annual, herbaceous member of the geranium family (Geraniaceae) is known to occur in woodlands and grasslands, often on clay. The species is characterized by having undivided, basal, shallowly lobed leaves with white petals that are sometimes tinged red to purple. The species was historically known from the Antioch Dunes, approximately 2.3 miles east of the project area.
Showy Madia (Madia radiata). This annual member of the sunflower family occurs in grasslands and woodlands and is known in Contra Costa and historically in the Pittsburg area. The species is characterized by showy golden ligulate flowers and sticky (glandular) herbage. Portions of the annual grassland habitats in the Project area represent potential habitat for the species.
Suisun Marsh Aster (Aster lentus). This perennial, herbaceous member of the sunflower family occurs in brackish and salt marsh habitats of the eastern Bay Area. The plants are characterized by white to purple ray flowers. This species occurs within the project area at the edge of New York Slough at the base of a boat ramp. Impacts to these plants would be avoided near the shoreline through HDD techniques for cable construction.
Impact TBIO-6: Potential Impacts to Special-status Plants. The undeveloped grasslands, seasonal wetlands (e.g., saltgrass and seasonal pool) and marshes adjacent to and within the onshore cable route for the Pittsburg Standard Oil Converter Station site would require trenching, drilling, and related construction activities. These areas contain native soils that provide potential habitat for numerous special-status plant species. This is a potentially significant impact.
Mitigation Measure TBIO-6a: Rare Plant Surveys. Because spring surveys have not yet been conducted in the Project area, prior to construction the entire Pittsburg Standard Oil Converter Station onshore cable route and undeveloped laydown areas, not including the developed and disturbed proposed converter station site or other roads or developed areas along the route, shall be surveyed by qualified botanist(s) for special-status plants at the appropriate flowering period using established CNPS and CDFG protocols (Appendix F).
Implementation Responsibility: Project proponent
Requirements and Timing: A qualified botanist shall conduct surveys during the appropriate flowering period using CNPS and CDFG protocols, which include up to three visits to this portion of the onshore cable route during different early-, mid- and late-bloom periods.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-6b: Avoidance of Rare Plant Populations or Compensation for Loss. If special-status plants are detected within the construction zone, or the immediate vicinity, mitigation to avoid impacts within 50 feet of these plants or to compensate for unavoidable impacts or degradation of suitable habitat for these plants shall be identified in coordination with CDFG in accordance with Section 1913(c) of the California Fish and Game Code. Mitigation includes protection of existing rare plant occurrences and habitats by rerouting alignments, as practical, to avoid impacts to special-status plant species, and protecting other grassland and seasonal wetland habitats in the areas where the plants occur. This shall be accomplished through the purchase of credits (at a 1:1 ratio) in an existing service-approved mitigation bank.
Avoidance can also be managed by narrowing the construction ROW at the plant population location and rerouting the cable to the other side of the easement. As a least-desired option, salvage of plants and potential seed bank soils and placement of these plants and materials in adjacent potential habitat that will remain undisturbed may also be considered. Any such salvage process should be planned and coordinated through oversight from a qualified plant ecologist or botanist.
Implementation Responsibility: Project proponent/construction contractor
Requirements and Timing: The rare plant survey report prepared for the Project shall be submitted to the City of Pittsburg upon completion.
Construction ROW shall be narrowed or rerouted as necessary to avoid rare plant populations during the construction phase of the Project.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-6a and TBIO-6b would reduce Impact TBIO-6 to a less-than-significant level.
Impacts to Potentially Occurring Special-status Plants in Laydown Areas. Both the proposed and alternative laydown areas for the Pittsburg Standard Oil Converter Station site appear to be a previously disturbed annual grassland habitat. However, no field survey or reconnaissance of these sites was conducted for this study. Native soils and vegetation may exist at these sites. These areas are also within mapped polygons of known historical occurrences of Big Tarplant and Showy Madia, rare plants that have the potential to still occupy these properties. Other special-status plants also have the potential to occur in these grasslands and could be destroyed or removed through use of these areas for construction laydown.
Impact TBIO-7: Potential Impacts to Special-status Plants from Laydown Areas. Use of the proposed and alternative Pittsburg Standard Oil Converter Station laydown areas has the potential to cause disturbance to existing plants and surface soils from construction activities and equipment, and alteration of the sites. These areas may contain native soils that provide potential habitat for special-status plant species. This is a potentially significant impact.
Mitigation Measure TBIO-7a: Rare Plant Surveys in Laydown Areas. Prior to construction, undeveloped portions of the proposed and alternative laydown areas (e.g., grassland) shall be surveyed by a qualified botanist for special-status plants at the appropriate flowering period using established CNPS and CDFG protocols (Appendix F). These portions of the Project area shall receive both early season (March-May) and late season (July-September) rare plant surveys by a qualified botanist.
Implementation Responsibility: Project proponent
Requirements and Timing: A qualified botanist shall conduct surveys during the appropriate flowering period using CNPS and CDFG protocols, and submit the survey report to the City of Pittsburg upon its completion before construction begins.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Mitigation Measure TBIO-7b: Avoidance of Special-status Plants. If special-status plants are detected within the laydown areas, or the immediate vicinity, mitigation to avoid impacts within 30 feet of these plants will be implemented. Mitigation includes protection of existing rare plant occurrences and habitats by preventing equipment, materials or other project related activities from disturbing the plants in order to avoid impacts to special-status plant species. Any special-status plant populations located during surveys shall be clearly identified, marked and fenced in order to adjust the extent of the laydown area to avoid the plants. Additionally, following surveys and identification of any sensitive resources, the perimeter of all laydown areas utilized will be fenced with a silt fence in order to prevent disturbances (e.g., soil disturbance, soil compaction, spills) outside of the designated laydown area.
Implementation Responsibility: Project proponent/construction contractor.
Requirements and Timing: If special-status plants are located in a laydown area then the plants and a 30 foot buffer around the plants will be clearly marked and fenced at least 15 days prior to any use of the laydown area for construction purposes. Regardless of whether special-status plants are located, a silt fence shall be placed around the perimeter of the laydown area at least 15 days prior to the beginning of construction.
A qualified biological monitor shall be required to be present and ensure that the mitigation measure is enforced during all Project-related activities that may impact special-status species.
Monitoring Requirements: City of Pittsburg to monitor and ensure compliance.
Resulting Level of Significance. Mitigation Measures TBIO-7a and 7b would reduce Impact TBIO-7 to a less-than-significant level.
4.5.3.3.2 Operations-related Impacts. No operations-related impacts are expected from the Pittsburg Standard Oil Converter Station, including ancillary facilities.
Baxter, Randall. 1999. Splittail Abundance and Distribution Update. California Department of Fish and Game- Central Valley Bay Delta Branch.
CDFG (California Department of Fish and Game). 2002. California's Plants and Animals. Habitat Conservation Planning Branch Web Page. www.dfg.ca.gov/hcpb/species. Sacramento, CA.
2003. List of California Terrestrial Natural Communities Recognized by The California Natural Diversity Database. Wildlife and Data Analysis Branch, The Vegetation Classification and Mapping Program, Sacramento, CA.
2005. California Natural Diversity Data Base. California Department of Fish and Game. Sacramento, CA.
CNPS (California Native Plant Society). 2001. Inventory of Rare and Endangered Plants of California – sixth edition. Rare Plant Scientific Advisory Committee, David P. Tibor, Convening Editor. California Native Plant Society. Sacramento, CA.
2005. Online Sixth Inventory of Rare Plants. http://cnps.web.aplus.net/cgi-bin/inv/inventory.cgi.
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Sibley, D. 2000. National Audubon Society The Sibley Guide to Birds. Published by Alfred A. Knopf, Inc., New York, NY.
USDA-SCS (U.S. Department of Agriculture-Soil Conservation Service). 1980. Soil Survey of Contra Costa County, California. In cooperation with University of California Agricultural Experiment Station.
1991. Soil Survey of San Mateo County, Eastern Part, and San Francisco County, California.
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U.S. Fish and Wildlife Service). 1988. National List of Plant Species That Occur in Wetlands: 1988 National Summary. U.S. Government Printing Office.
2005. List of endangered and threatened species that may occur in or be affected by projects in the Antioch North, Honker Bay, and San Francisco North quadrangles. Sacramento, CA.
Worldclimate. 2005. Web page accessed at www.worldclimate.com.
Zeiner, D.C., W.F. Laudenslayer, Jr., K.E. Mayer, and M. White, eds. 1988-1990. California's Wildlife. Volumes I, II, III. California Statewide Wildlife Habitat Relationships System, California Department of Fish and Game. Sacramento, CA.
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