900 INNES CLEAN UP
ENVIRONMENTAL CLEAN-UP & REGULATION
Before the park development can begin, the Boatyard must undergo an environmental cleanup to remediate 900 Innes. The San Francisco Bay Regional Water Quality Control Board (RWQCB) is the lead agency providing remedial oversight of the City’s voluntary clean-up of 900 Innes.
Since 2013, several studies have been completed at the Site to determine the type and levels of pollution present. Contaminants found in onshore soil and Bay sediment include metals, petroleum hydrocarbons, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. These chemicals are commonly associated with boat building and repair operations. The highest contaminant concentrations in the onshore soil were measured within the top 1 foot. Below this depth, the highest concentrations were measured near the historical boat launch. The highest contaminant concentrations in the Bay sediment were measured near the shoreline (purple area in figure below). Further offshore, contaminants were mostly buried under several feet of sediment, except in one isolated location where contaminants were found near the surface.
In addition to cleaning up the soil and sediment for use as a park, the remediation of sediments will allow and facilitate the development a more connected mudflat, tidal marsh and wetlands, and upland buffer and transition zone to support the variety of flora and fauna, including migratory birds, that would benefit from this habitat. As importantly, the proposed marsh and wetland edge and upland buffer habitat will provide a resilient shoreline that can adapt with rising sea levels, improve water quality through filtration of nutrients and sediments in groundwater runoff, and help stabilize soils and minimize erosion in these areas.
DRAFT CLEAN-UP PLAN
The City is carrying out a voluntary cleanup of the Site to protect both future park users and the environment. The Draft Cleanup Plan addresses pollutant impacts found on the Site. These impacts are categorized into two major areas that are targeted for cleanup: (i) onshore soils and (ii) nearshore and offshore Bay sediments. These cleanup areas are shown on Figure 1.
Cleanup goals and designs were developed for identified pollutants to protect future human health and aquatic uses at the Site. The onshore soils will be removed to depths of 2 feet and 5 feet (shown in green and yellow on Figure 1). The historical Shipwright’s Cottage will be saved and cleaned up during the cleanup work. All other debris will be removed. The nearshore sediments will be removed to a depth of 4 feet (shown in purple on Figure 1). Removed soils, sediments, and debris will be hauled off-site by truck to one or more appropriately permitted landfill facilities.
Soil removal on the onshore portion will be followed by geotextile placement (bright colored plastic net fabric), then by a Clean Cover of 2 to 5 feet of fill soil to restore final surface grades. The geotextile will act as a marker between the Clean Cover soil and native site soil. All fill soil will be tested prior to use to confirm it is clean. Clean Cover placement will eliminate exposure to any residual contamination in soil. Sediment removal in the nearshore area will also be followed by Clean Cover placement but will not include the geotextile marker. One area in the offshore sediments (shown as the dotted tan circle on Figure 1) will be capped with clean layer of sand.
Samples will be collected during the cleanup work to confirm that the cleanup goals are met. These efforts will protect future park users and plants and animals in the Bay.
Once cleanup has been completed, a Land Use Control and Site Management Plan (SMP) will be applied to the property. The Land Use Control requires that the Site uses protect the cleanup actions taken. The SMP sets forth procedures for soil handling to be used both during and following park construction to protect human health, the environment and make sure the Clean Cover is protected. The SMP will also ensure that deeper soil below the clean fill layer is handled properly and not brought to the surface.
A Phase I/II Targeted Brownfield Assessment was prepared by Weston Associates for Region 9 of the U.S. Environmental Protection Agency (EPA). An additional data gap analysis, also funded by the EPA, was performed by AECOM. Northgate Environmental conducted initial sampling and analysis, and Anchor QEA has developed the final Sampling and Analysis Plan, which has been approved by the Dredged Material Management Office, a joint program of BCDC, RWQCB, the California State Lands Commission, USACE, and the EPA. Also participating on this interagency organization are the California Department of Fish and Wildlife, the NOAA National Marine Fisheries Service, and the U.S. Fish and Wildlife Service who provide advice and expertise on permitting matters which may impact biological resources and sensitive habitat.
Anchor QEA is also developing the Quality Assurance Project Plan and RAP, which require EPA approval per grant funding terms. Final testing and field work will be performed by Leidos, Inc. A certified laboratory will run physical and chemistry analyses on all samples. A qualified remediation contractor will be selected as part of a public bid process conducted by the Department and the City’s Department of Public Works to perform the remediation per approved plans, drawings, and specifications.