Bridgette R. DeShields

San Francisco Bay Regional Monitoring Program, San Francisco Bay, California Has served on the Regional Monitoring Program (RMP) Technical Review Committee (TRC) since January 2000 and has been the committee chair for over 10 years. Provides technical review and oversight of the monitoring and related research programs. Areas of focus include sediment, water and biota tissue characterization; PCBs, mercury, nutrients, PAHs, pesticides, and selenium; stormwater runoff, emerging contaminants (including PFAS and microplastics); fate and transport modeling as well as identifying sources, pathways and loadings.

Evaluation of TMDLs in the Los Angeles Area Did a comprehensive literature review and evaluation of TMDLs for contaminants, bacteria and trash in the LA region as part of litigation support. Prepared technical reports evaluating best management practices. Also reviewed fish consumption advisories, TMDL target development, toxicity evaluations, and proposed management measures.

Shell Mounds Project, Ventura, California Reviewed technical reports regarding shell mounds offshore that remained after removal of drilling rigs. The public and the Coastal Commission want the structures removed. Assessed chemical and biological data and provided recommendations.

Extended Site Sediment Investigation, Sausalito, California Developed both a work plan and a sampling and analysis/quality assurance plan for the collection of Horseshoe Bay sediment data as part of an extended site inspection in support of the base realignment, closure of the U.S. Army East Fort Baker Facility, and transfer of the property to the National Park Service. Managed sampling efforts and conducted aquatic bioassays and chemical analyses of sediments. The study was designed to determine if historical East Fort Baker operational practices had caused any adverse impact to the adjacent Horseshoe Bay sediments of sufficient magnitude to warrant dredging. Assessed the data to describe the presence and extent of sediment contamination and associated risks to aquatic biota and wildlife, and presented an extended site investigation report. Risks were shown to be minimal and no action was concluded based on the risk evaluation.

Sediment Investigation and Bioavailability Assessment, Kansas Led an effort to characterize sediments in drainage channels leading from a former smelter site to a river in Kansas. Chemicals of concern included arsenic, cadmium, lead, and zinc. The field program included bulk sediment and porewater, including measures of acid volatile sulfide and simultaneously extracted metals and other parameters that were used in a weigh-of-evidence approach to assess risks to human and aquatic receptors. Successfully applied the approach to limit the findings of impacts to areas just downstream from the former facility.

Sediment Investigation, Pittsburg, California Conducted a sediment sampling and analysis program to evaluate potential risks to aquatic receptors offshore of a petroleum coke loading terminal. Sediment cores were collected, examined for the presence of coke, segmented, and analyzed for metals and PAHs. Used the results to evaluate whether aquatic communities exposed to offshore sediments were at risk from the presence of coke, and whether any remedial activities were needed. Conducted solid-phase bioassays on the samples with elevated coke content. Showed that the sediment, although containing high levels of coke, were not toxic to aquatic life and that chemical contaminant levels were at or below screening level. No remedial activities were deemed necessary.

Portland Harbor Superfund Site Investigations, Portland, Oregon Represented a client on the Portland Harbor Light Products Study Group. This group is investigating the distribution and potential effects on PAHs and other petroleum-related compounds in sediments within Portland Harbor as part of the Portland Harbor Superfund site investigations. Conducted a spatial analysis of the extent of PAH contamination within Portland Harbor to evaluate whether elevated levels of PAHs could be associated with light petroleum products terminals.

Sediment Assessment and Remediation Evaluation, Portland, Oregon Supported sediment assessment, risk assessment and remedial design effort for a former industrial property on the Willamette River. Assisted in developing a work plan for conducting a field investigation that includes sediment sampling, bioassay testing, coring, and passive sampling. The site was a former pesticide and chlor-alkali manufacturer, and COCs included DDT, monochlorobenzene, dioxins/furans, sodium perchlorate, and hexavalent chromium. Also evaluated the cleanup goals for PCBs.

Baypoint Oil Spill, Pittsburg, California Compiled data on the nature and extent of PAH and petroleum contaminants in sediment and surface water resulting from the spill. Staff conducted a toxicological and spatial analysis to determine the degree and spatial extent of the impacts. In addition, used PAH profiling (i.e., expanded PAH analysis) to evaluate the source of PAHs detected at various locations to distinguish impacts from the spill material from ambient conditions and other potential sources. Identified two distinct source materials.

Maintenance Dredging Project, Port of San Francisco, California Managed the port’s dredging program for 3 years, including designing and implementing sampling and analysis plans (SAPs), applying for and negotiating permits, designing and managing upland disposal of sediment, managing and inspecting dredging contractors, and conducting water-quality and circulation studies. Represented the port at meetings of local stakeholder working groups, including the long-term management strategy for San Francisco Bay meetings and the sediment quality guidelines working group. Negotiated dredged material suitability and permit conditions with the Division Material Management Office (DMMO), consisting of USACE, EPA, the Bay Conservation and Development Commission, RWQCB, CDFW, and the National Marine Fisheries Service. Prepared budgets, evaluated alternatives for dredged material disposal, and managed a project to design an upland rehandling facility for PAH-contaminated sediments.

Maintenance Dredging Program, Moss Landing Harbor District, California Managed the maintenance dredging program for Moss Landing Harbor, the largest fishing port between San Francisco and Los Angeles, for more than 4 years, including the successful preparation and implementation of SAPs, dredging plans, testing reports, and post-dredge reports. The main COC in sediments was DDT. Worked with USACE, CCC, and RWQCB in establishing a multiyear permit. Also responsible for designing, constructing, and operating an upland disposal site and restoring the site into a visitor-serving recreational area, including restoration of native coastal dune habitats, and working with USFWS pursuant to designation of the area as critical habitat. . Developed a CEQA document for the North Harbor expansion project which involved addressing coastal erosion issues and protection of eelgrass beds. Gave presentations at public meetings, interfaced with the press, and worked with a local congressman, as well as EPA’s congressional liaison. An assessment was conducted to support a dredged material management plan for navigational dredging of Moss Landing Harbor. Developed a work plan, summarized background information, and conducted a screening-level modeling analysis to estimate concentrations of pesticides in offshore sediments following a hypothetical set of dredging events. The results of the model were used to estimate ecological effects of dredged material placement over time. Analysis included a review and compilation of available information and literature for the site, evaluation of transport dynamics in the highly complex canyon environment, screening-level modeling of the mixing conditions at the disposal location (DCORMIX), transport and deposition of the suspended material plume (SSFATE), and recovery analysis (RECOVERY). The preliminary risk assessment and the supporting screening-level modeling analysis were summarized in a draft report and submitted for independent peer review. Peer review findings recommended additional data collection and modeling work to further support the conclusions of the screening-level study. Revisions to the report were in response to requests by the peer review panel. The conclusions of the report support the continued dredging and aquatic disposal of the dredged material, with no unacceptable risks.

San Mateo-Hayward Bridge Seismic Retrofit Project, San Mateo, California Assisted with environmental review and permitting. Key environmental issues included potential contamination of bay sediments; associated water-quality impacts; impacts to seasonal wetland habitat; temporary alteration or closure of public facilities; potential entrainment of steelhead trout during hydraulic dredging; and potential impacts to fish and marine mammals from noise, vibrations, and turbidity during construction. Conducted studies to assess the level of contamination of bay sediments to be dredged as part of the construction. Consulted with member agencies of the DMMO, investigated on-land and aquatic disposal options, and developed detailed cost estimates for these options. In addition, reviewed environmental databases, California Department of Transportation (Caltrans) maintenance records, and effluent data from outfalls in the vicinity of the bridge to investigate the potential for sediment contamination. Prepared a SAP for sampling and testing sediments in accordance with DMMO requirements (Tier II), which was approved by the DMMO and Caltrans. The results of the sediment testing were incorporated into agency permit application packages. Assisted in preparing the public notice to support an individual permit application from USACE under Section 404 of the federal Clean Water Act.

Sediment Remediation and Upland Source Tracing Activities, Electrical Generating Station, Hawaii Since 2014, Integral has been providing a range of technical services to a private party in association with the planned Superfund cleanup of PCB-impacted sediments in Pearl Harbor. Activities have included review and comment on RI/FS documents prepared by others for the U.S. Navy, sediment transport modeling to ensure remedy efficacy, and site-specific ecological risk assessment to support selection of alternative remedial action levels. The risk assessment included co-located sediment and invertebrate biota sampling to support site-specific risk calculations. The net result of these activities is a better, less costly proposed remedy and expected additional improvements to the final remedy during remedial design. Current work includes remedial design, permitting, and TSCA compliance. Other activities include developing a permitting plan for source removals in upland areas, outfalls and other conveyances.

Engineering Evaluation and Cost Analysis (EE/CA) and Remedial Design for Yosemite Slough, San Francisco, California Supported the PRP group in coordinating with the EPA Region 9 effort to develop an EE/CA for this site. Assisted EPA’s consultant by developing work plans and reports to support the EE/CA and assisting in the development of cleanup goals and permitting strategies. Also involved with risk evaluations, source investigations, and historical data evaluations, as well as the development of remedial alternatives. Studies conducted include geotechnical assessments, evaluations of the biologically active zone, and natural attenuation. Currently engaged in pre-design studies for the remedy.

Waterfront Sediment and Upland Area Remedial Action, Eureka, California Led a team for a sediment investigation and remedial action planning program to address offshore sediments and upland soils contaminated with metals and PCBs in downtown Eureka. PCB contamination was managed with oversight from the RWQCB (no involvement necessary from EPA’s TSCA group). Developed risk-based cleanup goals, an RAP, and an implementation plan, as well as mitigation plans for avian species and eelgrass. Successfully negotiated approval of the RAP with the North Coast RWQCB. Ultimately, the site will be redeveloped as open space and waterfront commercial development.

Site Assessment, Remediation, and Facility Closure at a Former Chemical Plant, Elk Grove Area, California Led a team in conducting site investigation and developing plans and implementing remedial activities at a former resin manufacturing facility. Chemicals of concern included phenolics, toluene, ethylbenzene and xylenes. Developed site-specific cleanup goals protective of groundwater, soil vapor, and human exposure. Developed a demolition and facility closure plan and implemented a sampling program. Developed a remedial action planand managed the excavation activities. Negotiated entrance into DTSC’s voluntary cleanup program and achieved closure from both DTSC and Sacramento County with no land use restrictions by demonstrating acceptable post-remedial conditions.

Environmental Investigation, Remediation, Risk Assessment, and Related Services at a Former Sawmill in Northern California, Fort Bragg, California Managed a multiyear, multisite investigation and remediation project at a former sawmill site in northern California slated for mixed use redevelopment. Primary constituents of concern were PCBs, VOCs, dioxins/furans and petroleum hydrocarbons. The assessment included both the 415-acre mill site as well as a ranch area offsite. Tasks included site investigations at five operable units (including sediments within a complex of ponds) and offshore sediments, risk assessment (human and ecological), background evaluations, dioxin characterization, pond and offshore sediment sampling, remedial planning, construction, demolition, and oversight, and negotiations with multiple regulatory agencies. The site is a high profile project managed by DTSC, but with input from RWQCB, CDFW, USFWS, NOAA, city and county agencies, and CCC. The project included multiple regulatory and permitting requirements specific to the coastal zone of California that require integration of archaeologists, Native American monitors, biologists, botanists, marine mammal specialists, and geotechnical and other engineering disciplines. Completed multiple investigation and monitoring reports, a remedial investigation, two remedial action plans (RAPs), and a risk assessment. Implemented 3 years of remedial actions for soil and groundwater including bioremediation of the petroleum-impacted soils. Also conducted a complex quantitative analysis to develop background levels for dioxins as well as a method for source identification. Conducted site-specific bioaccumulation assessments for metals and dioxins/furans in upland soils and pond sediments. Successes include a no further action for large areas of the site and the offshore sediments, implementation of various remedial measures, and a strategy to address pond sediments and the jurisdictional dam. Also achieved site certification for the offsite ranch and coastal portion. The coastal portion was sold/transferred to the city to create a coastal trail.

Comprehensive Investigation and Remedial Planning and Implementation, Antioch, California Served as project manager for a comprehensive investigation and remediation project at a closed paper mill. Developed work plans and technical reports in support of investigation activities under the AB2061 program. In addition, risk-based screening levels (RBSLs) were developed and presented in a report as were background levels. The background level report developed upper-bound background concentrations for metals using DTSC guidance but also presented an approach and rationale for determining whether dioxins/furans detected onsite were due to ubiquitous anthropogenic sources or site-related sources. Site investigations were conducted at eight properties. Chemicals evaluated included metals, dioxins/furans, volatile organic compounds (VOCs), semivolatile organic compounds (SVOCs), PAHs, OCPs, and herbicides. Risk evaluations were conducted for each of the subject properties based on an unrestricted land use scenario to support sale/transfer of the properties. Completed an RI/FS work plan to assess soil and groundwater and an underground utility investigation. Also, developed an RAP and a California Environmental Quality Act document and completed activities pursuant to DTSC’s Public Participation Guidance Manual, including developing a mailing list and an initial fact sheet and community survey; interviewing community members and local officials; developing a public participation plan (which included a community profile); and conducting a public meeting and responsiveness summary.

CEQA and Permitting for PAH Remediation Site, San Francisco, California Lead consultant for CEQA and permitting for a project involving multiple pier areas along the San Francisco Waterfront. The project will include dredging and capping of PAH-contaminated sediment with the RWQCB as the lead agency for CEQA. Permitting agencies include the USACE, Water Board and BCDC with consultations on essential fish habitat and endangered species with the CDFW, NOAA/NMFS and USFWS.

CEQA and Permitting for Remediation at a Former Wastewater Plant, Larkspur, California Developed a California Environmental Quality Act (CEQA) document (mitigated negative declaration) for a former wastewater plant with PCB contamination. The lead cleanup agency is EPA Region 9 (for TSCA) but the Ross Valley Sanitary District was the lead for CEQA. The assessment included an evaluation of air quality impacts using CalEEMod and greenhouse gas impacts as well as tribal consultations under AB52. Also updated the site’s wetland delineation and worked with the USACE to evaluate seasonal wetland impacts and related requirements. Follow-on work included obtaining grading and other permits for implementation of the remediation with the City of Larkspur and Marin County. Also closed out an existing construction stormwater permit.

CEQA and Permitting, Sewer Rehabilitation Projects, Ross Valley Sanitary District Lead on all permitting and CEQA work for RVSD. Includes obtaining permit from the USACE, CDFW (e.g., streambed alteration permits), and others for sewer rehabilitation, sewer replacements, sewer extensions and other related projects. Also conducts CEQA compliance reviews and CEQA documents, as needed. These have included Notice of Exemptions and Initial Study/Mitigated Negative Declarations.

Categorical Exemption for a Former Resins Plant, Elk Grove Area, California Worked with DTSC’s CEQA group to develop a categorical exemption (CatEx) for a remedial measure at the facility involving phenolics and solvents in subsurface soil. In order to move forward with the CatEx, cultural resources and biological resources at the site needed to be investigated. Also developed fact sheets and a community mailing list.

Risk Evaluation for Placement of Dredged Sediments at Winter Island, Winter Island Reclamation District, Sacramento Delta, California Developed “acceptability” criteria for placing contaminated sediments along levees at Winter Island. The Winter Island Reclamation District needed 500,000 yd3 of sediments to rehabilitate levees and, particularly, needs silty material to “cap” the levees and prevent erosion. Worked with the San Francisco RWQCB to develop levels of contaminants acceptable for material placed on levees, and also developed management and engineering practices to prevent erosion and migration of placed material to a nearby wetland. Contaminants evaluated included metals, PAHs, PCBs, and DDT.

CEQA and Coastal Zone Permitting for Remediation at a Former Sawmill, Fort Bragg, California Developed CEQA documents (categorical exemptions and mitigated negative declarations) for three separate interim remediation projects, developed fact sheets and a project website, attended and presented at public meetings, and led negotiations with multiple regulatory agencies. The site was a high profile project managed by DTSC and included multiple regulatory and permitting requirements specific to the coastal zone of California that required integration of archaeologists (due to sensitive subsurface cultural resources on the site), Native American monitors, biologists, botanists, marine mammal specialists, and geotechnical and other engineering disciplines. The CEQA documents supported two remedial action plans (RAPs). Also worked with City land use planners to incorporate the final remediation projects into a Specific Plan and EIR for the site reuse. The coastal portion was sold/transferred to the city to create a coastal trail. The three interim remedial measures were completed successfully.

CEQA and Coastal Permitting for Remediation at a Waterfront Site, Eureka, California Completed a CEQA document (mitigated negative declaration) for a remedial action program to address offshore sediments and upland soils contaminated with metals and PCBs in downtown Eureka. Project included upland excavation and dredging. Worked with various permitting agencies including the City of Eureka (lead CEQA agency), North Coast Regional Water Quality Board (lead remediation agency), USACE, CCC, the local Harbor District, CDFW, USFWS, and NOAA to issue project permits. Obtained a Nationwide 38 permit and water quality certification as well as a coastal development permit. Project included restoration of shoreline habitat and addressing impacts to benthic communities. Ultimately, the site will be redeveloped as open space and waterfront commercial development.

CEQA and Public Participation for Two Former Mills, Antioch, California Developed a CEQA document (mitigated negative declaration) for DTSC for an interim remedial measure at a former pond, including assessment of two federally endangered plant species and cultural resources. Also completed activities pursuant to DTSC’s Public Participation Guidance Manual, including developing a mailing list and an initial fact sheet and community survey; interviewing community members and local officials; developing a public participation plan (which included a community profile); and conducting a public meeting and responsiveness summary.

Human Health and Ecological Risk Assessment at a Former Petroleum Refinery, Lawrenceville, Illinois Prepared work plans for the human health and ecological risk assessment, including a problem formulation document. Conducted a baseline ecological risk assessment and baseline human health risk assessment (BHHRA) using the data collected as part of the remedial investigation. Provided strategic consulting related to the remedial investigation and risk drivers for remediation. Participated in agency meetings with Illinois EPA regarding risk assessment tasks. Several unique and innovative approaches were used, including use of area-weighting with Thiessen polygons to estimate exposure point concentrations, which overall improved risk estimates; site-specific prey tissue data; site-specific bioassays; and lead bioavailability testing, which also provided more site-specific estimates of bioavailability and risks and overall lower risk estimates. The risk assessment assumed a presumptive remedy area that also resulted in an overall more favorable impression of residual site risks. A site-specific assessment of lead bioavailability was also conducted.

Risk Assessments for Perchlorate at Space and Missile Propulsion System Test Facility, California Performed three risk assessments to assess potential perchlorate exposures. The first risk assessment, submitted to DTSC, was conducted to provide support for the Resource Conservation and Recovery Act post-closure permit application process for a former onsite station and three surface impoundments. Human health-based screening levels (HBSLs) for perchlorate in soil were developed based on a range of regulatory recommended provisional toxicity criteria for various exposure scenarios. The second risk assessment was submitted to the California RWQCB and consisted of both human health and ecological risk evaluations of potential exposures to perchlorate in soil and groundwater at three onsite areas. HBSLs for perchlorate in soil were developed based on direct contact exposures; protection of groundwater; and provisional toxicity criteria recommended by both Cal/EPA’s Office of Environmental Health Hazard Assessment and EPA. The third risk assessment was conducted to support potential compliance issues associated with the State of California’s Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65). Risk assessment methodologies were used to characterize and assess potential releases of perchlorate from onsite operations in order to evaluate notification responsibilities specified under Proposition 65 regulations. RBSLs were developed for ecological and human health receptors to support a site-wide RAP. Supported real-time decision-making during remediation and conducted a post-remedial risk assessment for this 5,000-acre site. The sitewide risk assessment assessed excavation and regraded areas and included land use restrictions where necessary to specify acceptable future uses. Assessed both human and ecological receptors, soil, groundwater, and surface water.

Risk-Based Assessment at a Former Tannery Site, Santa Cruz, California Conducted a risk assessment for former tannery based on specific site development plans. Evaluated potential exposures to chemicals in soil and groundwater for future residents and office and construction workers. Chemicals of concern included chromium(VI) and arsenic as well as VOCs and TPH. The risk assessment was used to inform the redevelopment plan. Provided target cleanup levels for soil and participated in public outreach programs, including presentations at city planning and city council meetings. Lead agency was the California DTSC. Site has now been built out as a mixed use live-work arts center.

Development of Approach for Assessing Risks to Livestock for Petroleum Hydrocarbons, Nationwide Developed a framework to determine when livestock should be included in a risk evaluation, and estimated risks of petroleum hydrocarbon exposure to livestock. A conceptual site model was developed to assess whether complete and significant exposure pathways exist at a given site. To estimate potential risks, TRVs, and drinking water and soil, RBSLs for petroleum hydrocarbons, including crude oil, benzene, toluene, ethylbenzene, and xylene, and PAHs were developed for a variety of livestock receptors. The TRVs and RBSLs developed for this framework were comparable to human health RBSLs and other published livestock guidelines. The approach can be adapted for assessing other chemicals (i.e., metals, PCBs, pesticides).

Risk Evaluations for Forest Products Sites, California Conducted risk-based screening assessments at several sites in Northern California on former sawmill sites. Sites include both Water Board and DTSC lead and evaluation of future residential and commercial land uses. Contaminants include petroleum products, metals, and dioxins/furans as well as some VOCs and semivolatile organic compounds (SVOCs). Also assessed waste management options for soil.

Assessment of Lead in Soil, Santa Rosa, California Conducted a risk assessment for soils along the Santa Rosa Creek corridor for the Sonoma County Environmental Health and Sonoma County Water Agency. Evaluated risks for a residential property adjacent to the creek as well as within the creek corridor itself. The primary issue was lead in soils from placement of fill material.

Toxicology Evaluation of Remedial Action Objectives, California Conducted an in-depth assessment of outdated remedial action objectives for a specific contaminated site in California. Reevaluated the toxicology and quantitative risk assessment for a specific unregulated contaminant of concern at the site. Calculated new screening levels based on updated risk assessment methodologies to ensure that remediation actions remain protective of public health.

Risk Assessment of Expedited Remedial Action Program, Golden Technology Site, Santa Rosa, California Complete site assessment and risk assessment activities, primarily for VOCs, at a site consisting of three parcels of land located in the southern portion of the City of Santa Rosa zoned for commercial use. DTSC was the lead agency for the program.

Fort Ord Ecological Risk Assessments, Monterey, California Performed quantitative human health and ecological risk assessment at 41 sites. Human receptors included residential, commercial/industrial, and recreational users. Ecological receptors included aquatic life, mammals, birds, reptiles, insects, and plants. Developed toxicity reference values (TRVs) and site-specific exposure assessments. Evaluated the results of bioassays on aquatic organisms and plants. Assessed possible impacts to special status species, characterized sites, conducted fate and transport analyses, and modeled exposure and effects. Site-specific studies included butterfly and lizard population surveys; collection and analysis of site-specific plant, reptile, and mammal tissues; a plant health and condition study; a leaf litter study; and an enhanced preliminary assessment for the offshore marine environment. Primary contaminants of concern were lead and other heavy metals associated with small arms, dioxins in burn-pit areas, petroleum hydrocarbons from motor pools (a site-specific total petroleum hydrocarbon [TPH] cleanup level was developed), and explosive compounds. Pesticides and PCBs were also found at some of the sites. Worked with the regulatory agencies (mainly EPA and DTSC, but with selected and focused involvement of USFWS, CDFW, and NOAA for specific aspects) in a cooperative manner, such that the agencies have been very supportive of innovative techniques for site characterization and risk assessment. Made presentations at public and technical group meetings and have presented data jointly with agency at scientific meetings. Worked with U.S. Army Center for Health Promotion and Preventative Medicine (USACHPPM) to develop methods to evaluate the bioavailability of lead and site-specific conditions at small arms firing ranges. The record of decision has been signed for all sites at Fort Ord. Additional work was undertaken at the unexploded ordnance range site, where the risk evaluation was conducted. Site-specific field studies on lead uptake into plants, insects, lizards, and small mammals have been conducted as well as site-specific bioavailability jointly with USACHPPM. The risk assessment included using this site-specific data and an approach aimed at balancing site cleanup, risk reduction, and preservation of rare and declining habitats is being used. This analysis was used to develop site-wide cleanup levels and a site-wide cleanup approach for this 8,000-acre area.

Ecological Risk Assessment in a Desert Environment, Topock, California Technical lead for an ecological risk assessment for several dry wash areas in the Mohave Desert near an operating facility. Main chemical of interest is chromium (total and hexavalent) as well as a number of other metals. Developed a conceptual site model and risk assessment work plan and contributed to site characterization work. Completed a groundwater risk assessment.

Ecological Risk Assessment for Sulphur Bank Mercury Mine, Clear Lake Oaks, California Conducted a terrestrial ecological risk assessment for the upland portions of the mine site. Mercury is the main contaminant of concern, although other metals with elevated levels were evaluated as well. Evaluation included assessing spatial scale of risks in relation to native plant populations and balancing restoration goals with cleanup efforts. Developed risk-based action levels for seven receptors and incorporating information about speciation/bioavailability of metals onsite. An assessment of cultural issues (ceremonial uses of plants and ingestion of game animals) important to the adjacent tribe was included. Tribe members participated in the scoping process, and the ultimate remedy was negotiated with EPA and the tribe representatives.

Ecological Risk Assessment, Presidio of San Francisco, California Conducted a basewide study to develop cleanup levels for aquatic and terrestrial receptors for the feasibility study to support future uses and redevelopment of the Presidio. Developed cleanup levels for metals, pesticides, PCBs, VOCs, and SVOCs as well TPH constituents. Negotiated the approach with the regulatory agencies and presented the cleanup levels at public meetings (restoration advisory board and other community work groups). Provided technical review and oversight of other contractors’ assessments, including other ecological risk evaluations and several studies to develop action levels for TPH. Conducted an evaluation to develop site-specific cleanup levels for TPH diesel and fuel oil in the freshwater riparian zone. Crissy Field Area: Conducted an HHRA for recreational receptors theoretically exposed to soil excavated from one area onsite to create a wetland, and disposed of at areas on site slated for future recreational use. Chemicals of concern included metals and PAHs. Used information from the risk assessment to finalize construction plans for the wetland. Lobos Creek Area: Conducted a data review and remedial investigation that recommended no further action for the creek and watershed.

Site Remediation Project, Casmalia, California Developed work plans, developed biological and endangered species reports, and negotiated an ecological risk assessment approach for the Casmalia Site Remediation Project, a former hazardous waste landfill site in central California. Conducted a multipathway, multispecies ecological risk assessment to address residual contamination from closed ponds and pads and areas around multiple capped landfills that held metals, solvents, PCBs, pesticides, sludges, and oily wastes. Species of concern at the site included red-legged frogs, western spadefoot toad, southwestern pond turtle, and other threatened and endangered species in both upland and aquatic areas. The ecological remedial assessment is designed to focus on areas that will not undergo presumptive remedies (i.e., landfill caps), mainly the liquid impoundments and some upland portions of the site used for disposal of waste. The approach focused on functional groups of receptors representing important components of the food web and will be conducted on a site-wide basis and in a phased manner. Participated in subcommittee meetings with the regulatory agencies and with the technical committee. Assisted the PRP group with issues related to natural resource damages and habitat restoration/mitigation. Produced a biological species and habitat survey report and an assessment of risks to burrowing mammals through inhalation of burrow air as part of the interim progress report for the RI/FS. Site-specific background levels, selection of chemicals of potential concern, and the ecological risk assessment have been completed and approved. A site-specific study of bioaccumulation and bioavailability was conducted. Following approval of the remedial investigation, developed cleanup goals and provided input to the Feasibility Study and selection of remedial alternatives.

Ecological Assessment of Petroleum Hydrocarbons, San Francisco, California Provided technical review of Tier 1 and Tier 2 screening levels for ecological receptors in the marine ecological protection zone of the San Francisco Airport developed by RWQCB. Reviewed and commented on the 3-dimensional migration models and bioassay tests used to develop TPH cleanup levels. Reevaluated the likelihood of petroleum hydrocarbons (TPH-diesel and benzene) in groundwater and soil detected near terminals at San Francisco Airport to migrate to San Francisco Bay. Estimated effects of TPH and benzene on aquatic receptors in the bay using site-specific information. Revised cleanup developed based on the results of this evaluation.

Ecological Assessment of Stormwater Runoff to a Freshwater Marsh, Fairfield, California Conducted a screening ecological assessment to evaluate the effects of metals and organic compounds in stormwater runoff and seepage from a natural spring on aquatic and terrestrial receptors at a freshwater marsh. Conducted a biological inventory to select indicator species for the assessment. Developed screening criteria based on applicable state and federal freshwater sediment and surface-water criteria. Identified areas of concern and recommended additional site characterization.

Milepost 68 Oil Spill, Utah Conducted an ecological risk assessment to evaluate potential effects on aquatic and wildlife receptors potentially exposed to petroleum products in freshwater marsh sediments due to a pipeline break. A cleanup level of 20,000 parts per billion for total PAH was negotiated with EPA, USFWS, and the State of Utah.

Risk Communication and Risk Assessment, San Francisco, California Evaluated site data (soil, groundwater, soil vapor and indoor air) for a daycare center that was formerly a dry cleaner site. Assessed the potential for adverse health effects to daycare workers and children through site-specific risk assessment. Developed a communication plan and talking points and presented findings at a meeting with parents and daycare workers. Assisted in the development of recommended actions/next steps.

Soil Vapor and Indoor Air Evaluation, Napa, California Assessed risk and developed risk communication plans for a large former dry cleaner site with a plume extending under homes and a bed & breakfast. Developed a communication plan, fact sheet and talking points for residents and other neighbors. Also assisting in the development of soil vapor and indoor air sampling plans. Constituents of concern were TCE, PCE and vinyl chloride. Site is under the lead of the SF RWQCB. Remedial action planning is ongoing.

Soil Vapor and Indoor Air Evaluation, Oakland, California Assessed risk for a large former UST site with residual NAPL and benzene. The groundwater plume extended under an apartment building with a basement and adjacent commercial buildings. The property owner of the apartment was concerned about residents; an indoor air sampling program was developed. Met with the regulatory agency to discuss the next steps and additional data needs to support a risk assessment and site cleanup plan. Additional characterization and remedial action planning is ongoing.

Litigation Support for Contaminated Sediments, San Francisco Bay, California Provided expert support on a 3-party litigation case involving an advocacy group and metals contamination in an estuary.

Litigation Support for Contract Dispute, San Diego, California Provided an support for a mediation process involving a dispute over payment for disposal of materials as hazardous waste. Required knowledge of California and federal waste regulations.

Litigation Support for PCBs Consulting expert for multiple cases involving PCB contamination.