610 (CAR-1117-818891) Management decisions to identify regulatory response to address contaminated sediments at an industrial site in San Diego Bay.
Start time: 8:00 AM
Carlisle, C¹, MacDonald, D², Alo, T¹, Monji, A¹, ¹ California Regional Water Quality Control Board, San Diego, California, USA² NOAA Office of Response and Restoration, Seattle, Washington, USA
Environmental management decisions are required at several steps during the process of identifying the appropriate regulatory response to address contaminated sediments. Discharges from a variety of sources have resulted in the presence of elevated metal and organic compound concentrations in San Diego Bay sediments that potentially threaten aquatic life, aquatic-dependent wildlife, and human heath. The data collected during an investigation of an industrial site located in San Diego Bay includes sediment chemistry, sediment toxicity, benthic community structure, bioaccumulation potential, pore water concentrations, marine life tissue residuals, fish histopathology, and fish bile metabolites. Environmental management decisions necessary during the process of interpreting these data include: identification of background, decision rules for each leg of the triad, measures of benthic community health, parameters for conducting human health and wildlife risk assessments, and statistical methods and thresholds for comparisons to reference areas within San Diego Bay. Environmental justice considerations arise regarding fish consumption (e.g. consumption rates, whole body or fillets) and potential remedial response (e.g. truck traffic, air pollution). Each management decision point impacts the subsequent decision regarding the appropriate regulatory response to the questions: is remediation required and, if so, what are the appropriate cleanup levels. Stakeholders involved during the investigation and subsequent cleanup process include industrial and non-point source dischargers, federal natural resource trustees, environmental advocates, and recreational and subsistence anglers.

611 (ZAM-1117-842764) Development of a Sediment Residuals Performance Standard for the Hudson River PCB Remediation.
Start time: 8:20 AM
Garvey, E², Zamek, E¹, Hunt, C⁴, Warner, L¹, Kresic, N³, Hess, A⁵, Fidler, B², ² Malcolm Pirnie, Inc., Fair Lawn, NJ¹ Malcolm Pirnie, Inc., White Plains, NY⁴ Earth Tech, Bloomfield, NJ³ Malcolm Pirnie, Inc., Washington DC⁵ United States Environmental Protection Agency, Region 2, New York, NY
In February 2002, the US Environmental Protection Agency (USEPA) issued a Record of Decision (ROD) for the Hudson River PCBs Superfund Site. The ROD calls for environmental dredging of approximately 2.65M cubic yards of PCB-contaminated sediment from the Upper Hudson River, making it one of the largest sediment remediation projects ever proposed under Superfund. The ROD also requires the development of rigorous engineering performance standards to address the resuspension of PCB-bearing sediments, the residual concentration of PCBs in the sediment surface after dredging, and the completion of the sediment removal in six years. Rigorous dredging-related performance standards are a unique new requirement for site remediation, and those designed for the Hudson are designed to closely monitor the operation, protect downstream water users, ensure the anticipated long-term recovery of the river and minimize the disruption to the local community. The Engineering Performance Standard for Dredging Residuals, developed to address the post-dredging PCBs concentration in residual sediment, defines criteria developed through statistical analysis on case study data originating from sites with contamination and remedial strategies similar to those at the Hudson River site. Statistics for the case study data were extensively evaluated to support of the specifications of the performance standard. The statistical analysis results yielded three major conclusions: that the concentration of residual sediment concentration are not spatially correlated, that the amount of variance in the residual sediment concentration varies directly with the magnitude of the residual contamination concentration (the variation is a constant percentage of the mean residual concentration), and that the distribution of residual sediment concentrations was skewed, characterized more appropriately by a lognormal distribution than a normal one. The statistical results were used to develop a set of numerical action levels and decision trees that provided a framework for dealing with residual contamination.

612 (BAY-1117-850689) Development of California marine sediment quality objectives using a mulitiple line of evidence framework.
Start time: 8:40 AM
Bay, S¹, Beegan, C², Vidal, D¹, Ranasinghe, J¹, Connor, M³, Greenfield, B³, Weisberg, S¹, ¹ Southern California Coastal Water Research Project, Westminster, CA, USA² California State Water Resources Control Board, Sacramento, CA, USA³ San Francisco Estuary Institute, San Francisco, CA, USA
Few states have adopted a regulatory policy for sediment quality management that includes numeric values for sediment contamination. Uncertainty and debate regarding the efficacy and reliability of chemistry-based sediment quality criteria have generally resulted in the establishment of nonregulatory guidance that places the burden on local regulators to determine how to interpret sediment quality data. California is developing a sediment quality objectives policy for bays and estuaries using a novel approach that is based on a multiple line of evidence assessment (MLOE) framework. This approach is a significant departure from other programs in several respects: 1) the sediment quality triad of chemistry, toxicity, and benthic community health is formally incorporated into policy; 2) new and refined benthic community indices specific to California habitats have been developed, 3) numeric thresholds for each line of evidence were developed using a regional database; and 4) a MLOE assessment framework has been developed that provides both a definitive conclusion regarding sediment quality and an ordinal classification useful for prioritizing impacted sites. Similar MLOE assessment frameworks were also developed for assessing sediment contamination relative to impacts on human health and wildlife, but additional data are needed to address site-specific issues related to variations in prey species, wildlife receptors, and fish consumption rates.

613 (THI-1117-852650) Soluble contaminant release during bed sediment removal and resuspension-Chemodynamic model predictions.
Start time: 9:00 AM
thibodeaux, l¹, birdwell, j¹, reible, d², ¹ louisiana state university² university of texas-austin
Particles are placed in the water column by both natural and engineered processes. The numerical mass quantities typically suspended per mass extracted by dredges and the loadings observed following storm runoff flow events impacting streams will be reviewed. While in suspenstion a fraction of the particle-sorbed contaminant mass is solubilized. Numerous kinetic experiments involving a wide range of organic chemical types suggest that a bi-phasic rate process consisting of a fast and slow release fraction has been consistently observed by many investigators. These data sets including summaries of rate constants, soluble fractions, etc., will be presented and reviewed briefly prior to presenting the chemodynamic model developed for quantifying the release processes of dredges operating in flowing streams. A kinetics-based rather that the usual thermodynamics, chemical equilibrium-based model will be developed for forecasting water column concentrations need for estimating biota up-take quantities and other water quality parameters. The processes modeled using a mass balance approach include: particle generation, particle settling, fast and slow solubilization from particles, solubilization from the bed sediment bottom layer and evaporation to air for assumed plug-flow stream hydraulics. For steady-state dredging rate a key model output is concentration in water vs distance downstream. Typical results for mechanical and hydraulic dredges operating at a well characterized site containing PCBs(Aroclor 1242)will be presented. Elevated suspended solids levels of 6.0 to 20 mg/litre decreased exponentially but low levels remained up to 4 days. The total, sorbed plus souble, PCB concentration decreased similarly from initial values of 1.3 to 2.6 ug/litre. Interestingly, the soluble concentration was highest well downstream the dredge site. Levels of 1.5 to 1.9 ug/litre above the equilibrium ones were predicted to occur 5 to 15 hours flow-time or at 0.6 to 1.7km distance downstream. Although site specific these results should be of interest to those designing dredging operations for minimizing biota and related water quality impacts. Steady-state concentration levels were predicted to occur at 4 to 5 days flow-time or 11 to 14km downstream.

(58494) Break.
Start time: 9:20 AM

614 (EMS-1116-970281) Synergistic Source Identification and Risk Assessment Approach for Sediment Investigation in Narragansett, Rhode Island.
Start time: 10:00 AM
Emsbo-Mattingly, S¹, Hinkley, D², Speicher, J³, Leather, J⁴, Yeutter, L³, ¹ NewFields, Roskland, MA, USA² EA Engineering, Science, and Technology, Inc., Sparks, MD, USA³ U.S. Navy Engineering Field Activity Northeast, Lester, PA, USA⁴ U.S. Navy Space and Naval Warfare, San Diego, CA, USA
The ever increasing convergence of risk assessments and source identification in ports and harbors is largely a function of improved conceptual site models, refined chemistry methods, and sophisticated source identification tools. The need for lower detection limits and source signature traceability is readily demonstrated at sites with regulatory action levels approach local background conditions. Under these circumstances, the proliferation of non-detects threatens to increase uncertainty within the risk assessment and obscure compositional differences between point and non-point source releases. This presentation features the use of modern techniques for measuring the concentration and character of polycyclic aromatic hydrocarbons (PAHs) and associated material for the purposes of distinguishing sediment impacts from a creosote operation, fire fighter training area, and marina facility in a harbor off Narragansett Bay, Rhode Island. In this study, the use of alkylated PAHs, biomarker fingerprints, total organic carbon (TOC), and rapid sediment characterization (RSC) protocols helped attribute most of the PAH contamination to background and local marinas. These data helped the Navy project team complete a screening-level Ecological Risk Assessment (SLERA) with a more clear understanding of PAH sources and remediation priorities.

615 (STE-1117-856869) The association of floodplain PCB contamination to sediments of the Upper Hudson River.
Start time: 10:20 AM
Steinbacher, J¹, Shorr, B², ¹ NOAA Damage Assessment Center, Silver Spring, MD, USA² NOAA Coastal Protection and Restoration Division, Seattle, WA, USA
Natural resources of the Hudson River have been contaminated through past and ongoing discharges of polychlorinated biphenyls (PCBs). The Hudson River Natural Resource Trustees: New York State, the U.S. Department of Commerce, and the U.S. Department of the Interior, are conducting a natural resource damage assessment (NRDA) to assess and restore those natural resources injured by PCBs. Several studies conducted from 2000 to 2004 have examined PCB contamination in floodplain soils and biota of the Upper Hudson River Valley, between Bakers Falls (RM 197) and Schodack Island (RM 132). PCB concentrations of floodplain soil samples were as high as 360 ppm and PCBs in biological samples reached concentrations greater than 50 ppm. The 65 miles of river that were studied were divided into four regions and the total PCB concentrations as well as PCB homologues and congeners of the floodplain samples showed similar spatial trends as found in the sediments of corresponding regions. In general, PCBs showed a decreasing downriver concentration gradient and a corresponding shift in PCB homologue and congener composition from lighter to heavier molecular weight compounds. These spatial contamination trends suggest a linkage to sediment-associated PCBs and a pathway from river sediments to the floodplains.

616 (REI-1117-511061) Organoclay for the control of NAPLs in sediments.
Start time: 10:40 AM
Reible, D¹, Lu, X¹, Blischke, Heidi², ¹ University of Texas, Austin, TX, USA² Oregon Department of Environmental Quality, Portland, OR, USA
Conventional capping of contaminated sediments with sand or other inert materials may not be effective in areas where sediments contain nonaqueous phase liquids (NAPLs) due to displacement or continued migration of NAPLs. Organoclays have been proposed as an active capping material for control of NAPLs and were used at the McCormick & Baxter Creosoting Company site on the north shore of the Willamette River in Portland OR. The Oregon Department of Environmental Quality, in cooperation with the University of Texas, undertook a simultaneous laboratory study of organoclay in order to 1) to better understand the effectiveness of organoclay to control NAPLs and 2) to obtain information that will shape the long-term monitoring and maintenance plan for the McCormick and Baxter organoclay cap. The flow and sorption characteristics in the organoclay after exposure to site water and NAPLs were monitored and used as a basis for understanding the feasibility and effectiveness of organoclays for NAPL control. Organoclays were found to provide good control of both dissolved and nonaqueous phase contaminants. Contact with organoclay gave rise to significant swelling and a simultaneous reduction in effective permeability of the organoclay. This could serve to enhance effective utilization of organoclays by forcing lateral migration around seeps but also discourage subsequent migration of NAPLs into a treatment layer. Implications of these results for the design and implementation of organoclays for NAPL control in sediments were assessed.

617 (ACC-1117-827117) Evaluation of sedimentation rates and solids transport in the Lower Passaic River.
Start time: 11:00 AM
Accardi-Dey, A.¹, Garvey, E.², How, C.¹, Desai, M.¹, Zamek, E.¹, Zeiner, C.¹, ¹ Malcolm Pirnie, Inc., White Plains, New York, USA² Malcolm Pirnie, Inc., Fair Lawn, New Jersey, USA
The Lower Passaic River has historically been subject to artificial deepening for navigation as well as contaminant-laden industrial and municipal discharges. Understanding the impacts of these activities is of major importance in planning remediation and managing the estuary under CERCLA and WRDA. To this end, a preliminary study of sediment deposition of the Lower Passaic River was performed using bathymetric and sediment core data collected from 1990 to 2004 from river mile (RM) 0 to RM 15. This presentation will focus on the lower six miles of the river due to the greater density of data in that area. In general, this analysis suggests that sedimentation rates (calculated by two independent methods: radioisotopes and bathymetry) are spatially heterogeneous from RM 0 to RM 6, varying from areas characterized as non-depositional/scour to areas with measured deposition rates greater than 5 inches/year. Moreover, differences between bathymetric surfaces (collected in 1995 and 2001) suggest that depositional rates vary significantly with water depth as well as river location, resulting in high sedimentation rates in the channel and low sedimentation rates on the shoals, opposite of that expected in an estuarine setting. Notably, a large depositional zone is located at the mouth of the Passaic River, characterized by a wide area of sedimentation rates greater than 3 inches/year. Integration of sediment accumulation rates show reach-by-reach variation in the net rate of sediment gain or loss. This evidence along with other geochemical data suggests that a net transport of solids is occurring from the Passaic River to Newark Bay. Sediment core evidence confirms the occurrence of high rates of sediment deposition while also providing evidence to characterize the impacts of historical flood events on accumulating sediments. These observations are important initial components of the overall body of evidence approach for the Lower Passaic River Restoration Project.

618 (KLO-1117-832861) Organic contaminants in Baltimore Harbor sediments: phase distribution and accumulation by Nereis in laboratory exposures.
Start time: 11:20 AM
Klosterhaus, S¹, Fisher, D², Ziegler, G², Unger, M³, Baker, J¹, ¹ University of Maryland Chesapeake Biological Lab, Solomons, MD, USA² University of Maryland Wye Research & Education Center, Queenstown, MD, USA³ Virginia Institute of Marine Science, Gloucester Point, VA, USA
As part of a larger effort to determine the chemical-specific source(s) of sediment toxicity in Baltimore Harbor, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and mono-, di-, and tri- butyltins (MBT/DBT/TBT) were quantified in sediment and pore water collected from 8 sites within the Harbor in August of 2004. PAH (42 total) ranged from 3000-20000 ng/g dry in sediments and 90-300 ng/L in pore water. PCB (111 congeners total) ranged from 90-1400 ng/g dry in sediments and 2-25 ng/L in pore water. In sediments, TBT was detected at all sites (7-170 ng/g dry), while DBT was detected at only half the sites (2-30 ng/g dry) and MBT was not detected at any sites (DL < 2 ng/g dry). MBT, DBT, and TBT were not detected in pore water at any sites (DL < 10 ng/L). Concentrations of the flame retardants PBDEs (34 congeners total, including BDE 209) in sediments and pore water will be reported, providing the first measurements for Baltimore Harbor and their sediment-pore water partitioning in an estuarine environment. Bioaccumulation experiments were conducted using the same sediment where uncontaminated Nereis virens were exposed to sediments from 5 Harbor sites plus a reference control site for 28 days. At one of the sites a time series sampling regime was conducted, during which N. virens were collected on days 2, 4, 8, 16, 28, and 56 of exposure to Harbor sediment (uptake phase) and then on days 7, 14, and 21 after being transferred to control sediment (depuration phase). Concentrations of PAHs, PCBs, PBDEs, and butyltins in N. virens after exposure to Harbor sediments will be discussed, as well as the influence of sediment and pore water as exposure routes of organic contaminants to a representative deposit-feeding species exposed to a highly contaminated, estuarine sediment matrix.