Grantee Research Project Results
2003 Progress Report: A Multidisciplinary Approach to Quantify and Model the Transport and Deposition of Organic Pollutants in Coastal Environments: Science and Engineering Environmental Research (SEER) Project #1
EPA Grant Number: R829424E02Title: A Multidisciplinary Approach to Quantify and Model the Transport and Deposition of Organic Pollutants in Coastal Environments: Science and Engineering Environmental Research (SEER) Project #1
Investigators: Goni, Miguel , Ferry, John L. , Voulgaris, George , Styles, Richard
Current Investigators: Goni, Miguel , Ferry, John L. , Voulgaris, George
Institution: University of South Carolina at Columbia
EPA Project Officer: Chung, Serena
Project Period: October 1, 2001 through September 30, 2003
Project Period Covered by this Report: October 1, 2002 through September 30, 2003
Project Amount: $198,993
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2000) RFA Text | Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)
Objective:
The objectives of this research project are to:
- examine the dynamics between flow, sediment resuspension, and bound particle substances in an estuarine environment through measurements of fluxes of water, suspended sediments, and dissolved, colloid-bound, and particle-bound substances in Winyah Bay, SC;
- estimate the residence time of polycyclic aromatic hydrocarbons (PAHs) in this estuary;
- estimate the impact of photochemical degradation of PAHs on the total estuarine loading;
- determine the sources of PAHs and their carrying phases in Winyah Bay;
- and integrate our measurements in the new three-dimensional U.S. Environmental Protection Agency (EPA) model (Environmental Fluid Dynamics Code).
Progress Summary:
The flow conditions in the estuary have been examined, and the conditions observed during the field campaigns (low river discharge) have been analyzed. Concentrations of particulate organic matter (POM) for a variety of tidal stages and spatial locations within the estuarine environment were obtained using laboratory analyses. Analyses of PAHs in suspended particulate samples obtained through continuous flow centrifugation of large volume water samples have been performed at one site (near the estuarine turbidity maximum). Quantitative PAH analyses were performed using selective ion monitoring by gas chromatography-mass spectrometry. Quantification of PAHs in small volume water samples collected in other regions of the estuary was difficult because of the low concentrations encountered throughout most of the water column. Processes of PAH adsorption onto particles and PAH photodegradation were studied.
The physical component of the study examined the water circulation. Our findings suggest that for low-discharge conditions in the upper and middle estuary, the deeper, dredged main channel of an estuary acts as a conduit for landward delivery of salt water, but the surface riverine water flows out through the shallow western channel.
The channel in the lower estuary shows seaward residual currents throughout the whole water column; the channel bank system is under a different hydrodynamic regime exhibiting a landward residual flow. This implies that the residual flow in the mouth of the estuary is predominantly controlled by a tidally induced component rather than a density-driven component. The highest total suspended sediment (TSS), particulate organic carbon (POC), and particulate nitrogen (PN) concentrations were measured at the estuarine turbidity maximum (ETM), which is located in the upper/middle part of the estuary. TSS and POC generally showed a positive correlation with tidal magnitude and direction, with the highest values occurring during maximum flood. Under the low discharge regime encountered during this study, a net landward flux of TSS, POC, and PN along the main channel was calculated in Winyah Bay.
PAH concentrations are reported only for the area of the ETM where concentrations were high and large volume samples were taken. In the other stations, where only small volume water samples were taken, the PAH concentrations were very low and were comparable to our quality control blanks.
PAHs are hydrophobic and typically associated with organic matter (OM). Because POC showed a net landward flux during periods of low discharge, we suggest that PAHs also are trapped in the vicinity of the ETM, thereby increasing their residence time in the estuarine environment.
Circulation studies showed that the morphology of the estuary controls the net circulation that, in turn, defines the location of sediment, OM, and PAH accumulation.
The suspended POM is predominantly of terrigenous C3 plant origin, with significant contributions from river and estuarine phytoplankton. There is no measurable input from marine phytoplankton or C4 terrestrial vegetation such as Spartina alterniflora.
In terms of practical applications, our research suggests that the sensitive areas for PAH accumulations in estuaries are a function of relative position of PAH source through the estuary domain. Overall, the ETM could be assigned as a PAH indicator because the residual circulation appears to concentrate sediment and pollutants to this area. Thus, it is proposed that in evaluating the overall health of estuarine environments, the ETM should be sampled.
Future Activities:
We will:
- collect additional field data on circulation for periods of higher discharge;
- investigate the implementation of a finite element model to simulate the hydrodynamic and sediment transport conditions that will conform better to the morphological features of Winyah Bay;
- continue some of the PAH and POC analyses from the samples collected during Years 1 and 2 of the project;
- and integrate all results into a final report and publications.
Journal Articles on this Report : 4 Displayed | Download in RIS Format
Other project views: | All 19 publications | 6 publications in selected types | All 5 journal articles |
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Kim YH, Voulgaris G. Effect of channel bifurcation on residual estuarine circulation: Winyah Bay, South Carolina. Estuarine Coastal and Shelf Science 2005;65(4):671-686. |
R829424E02 (2003) R829424E02 (Final) |
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Styles R, Glenn SM. Modeling bottom roughness in the presence of wave-generated ripples. Journal of Geophysical Research-Oceans 2002;107(C8):24-1--24-15. |
R829424E02 (2003) R829424E02 (Final) |
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Styles R, Glenn SM. A theoretical investigation of bed-form shapes. Ocean Dynamics 2003;53(3):278-287. |
R829424E02 (2003) R829424E02 (Final) |
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Styles R, Glenn SM. Long-term sediment mobilization at a sandy inner shelf site, LEO-15. Journal of Geophysical Research-Oceans 2005;110(C4):04S90, doi:10.1029/2003JC002175. |
R829424E02 (2003) R829424E02 (Final) |
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Supplemental Keywords:
sediments, marine, estuary, absorption, chemical transport, risk assessment, organics, environmental chemistry, monitoring, analytical, surveys, measurement methods, general circulation models, discharge, southeast, Atlantic coast, estuaries, Winyah Bay, South Carolina, SC , polycyclic aromatic hydrocarbons, PAHs, ecosystem protection, environmental exposure and risk, geographic area, waste, water, contaminated sediments, ecology and ecosystems, hydrology, state, chemical mixtures, aquatic biota, aquatic ecosystems, aquatic life, bioavailability, biogeochemical partitioning, coastal, contaminant transport, contaminated sediment, ecological research, ecology assessment models, erosion, fate and transport, organic pollutants, predictive understanding, resuspension, sediment transport,, RFA, Scientific Discipline, Waste, Water, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, Hydrology, Contaminated Sediments, Environmental Chemistry, State, Fate & Transport, chemical mixtures, Ecology and Ecosystems, aquatic life, biogeochemical partitioning, aquatic ecosystem, fate and transport, organic pollutants, contaminant transport, erosion, predictive understanding, resuspension, sediment transport, transport contaminants, bioavailability, contaminated sediment, PAH, modeling, aquatic ecosystems, South Carolina (SC), ecology assessment models, aquatic biota, ecological researchRelevant Websites:
http://www.geol.sc.edu/gvoulgar/students/Kim/WinyahBay.htm Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.