Final Report: Pollutant Fluxes to Aquatic Systems via Coupled Biological and Physicochemical Bed-Sediment ProcessesEPA Grant Number: R825513C011
Subproject: this is subproject number 011 , established and managed by the Center Director under grant R825513
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: HSRC (1989) - South and Southwest HSRC
Center Director: Reible, Danny D.
Title: Pollutant Fluxes to Aquatic Systems via Coupled Biological and Physicochemical Bed-Sediment Processes
Investigators: Reible, Danny D. , Thibodeaux, Louis J. , Valsaraj, Kalliat T. , Fleeger, J. W.
Institution: Louisiana State University - Baton Rouge
EPA Project Officer: Hahn, Intaek
Project Period: January 1, 1995 through January 1, 1998
Project Amount: Refer to main center abstract for funding details.
RFA: Hazardous Substance Research Centers - HSRC (1989) RFA Text | Recipients Lists
Research Category: Hazardous Substance Research Centers , Land and Waste Management
The objectives for the second half of this research were to: a) expand the database relating the nature and magnitude of contaminant release by bioturbation, from a functional-group perspective by investigating additional bioturbating species, b) evaluate the effectiveness of our laboratory model by examining bioturbation impacts on field-contaminated sediments, c) initiate studies of metals release from sediments via bioturbation caused by changes in redox conditions, d) continue to improve the predictive capability of contaminant fate and transport models using the results from a-c, and e) initiate studies to determine the significance of bioturbation-related flux on aquatic systems in the field. A final objective was to explore the possibility that laboratory flux measurements can be used to provide a better indicator of adverse ecological impact than total sediment concentration.
As with the previous experiments, small experimental microcosms were employed to evaluate contaminant flux. The experimental chambers consist of a small plexiglass chambers, 15cm x 5 cm x 4.5 cm. The sediment (with or without bioturbators) is loaded into the chamber and water flowed over the top at rates of 500 ml/h. The effluent is collected at selected time intervals and the concentration of the contaminant determined using an HPLC. The flux of contaminant to the water thereby determined. The incurrent water is an artificial pond water (0.5 mN NaCl, 0.2mM NaHCO3, 0.05 mM KCl, 0.4 mM CaCl2). The sediment used is a native Louisiana sediment contaminated with polyaromatic hydrocarbons in the laboratory. Different organisms were placed within these microcosms and their effect on contaminant fate and transport evaluated. Redox probes were constructed in the laboratory to evaluate the impact of the organisms on redox conditions within the experimental microcosms.
For some experiments, small centrifuge tubes were employed in which organisms could be placed and covered with a porous cloth. Fecal matter could be collected on this cloth and analyzed to determine egestion rate, chemical defecation rates and complete a material balance on the chemical contaminants.
In addition to the experiments, significant work was directed toward developing conceptual, simple analytical and sophisticated numerical models of bioturbation. These were calibrated and tested against the experimental date collected.
Analyses of the effect of bioturbation by species other than tubificid oligochaetes showed that these conveyor belt organisms likely dominate contaminant transport and the modification of sediment properties by bioturbation. The effect of an amphipod species (Hyalella azteca), another abundant species in freshwater sediments on flux to the water column was observed to be only marginal, and may be related to it functional group. H. azteca is a shallow burrowing, surface deposit feeder that selects particles rich in food but does not digest bulk quantities of sediment. The effect of Hyalella azteca on flux was slight because its feeding activity was limited to very shallow depths. Thus, functionally, this species is quite different from tubificid oligochaetes, and our research suggests that not all bioturbators will have equivalent effects on contaminant flux. Similarly, the effects of a chironomid fly larvae were effectively negligible. These organisms were also more sensitive to the presence of the contaminants than the tubificid oligochaetes, again suggesting that their effects are negligible in a heavily contaminated sediment.
Studies of a field-contaminated sediment from Rouge River, Michigan, showed that the experimental apparatus could also be employed to examine bioturbation related release of contaminants in these sediments. The tubificid oligochaetes under study were extremely active in the Rouge River sediments, which contain up to 4% oil and grease. Quantitative measurement of contaminant release rates were difficult to assess due to the large amount of organic and colloidal material released to the water column by organisms processing these sediments.
The experiments were not extended to metals release but instead focused on the changes in redox conditions in the upper layers of sediment due to the activity of the organisms. The depth and extent of oxidation of the sediment was enhanced by the presence of bioturbating organisms. Some preliminary experiments with selenium indicated that this did influence the speciation of the element, increasing the amount of mobile oxidized species.
Several models were prepared and calibrated to the experimental observations. Conventional advection -diffusion type models were capable of describing the bioturbation phenomena but had very little predictive capability. A statistical Levy-flight model was constructed that potentially has much greater capabilities for prediction due to its ability to more closely simulate the finite movements that occur when organisms burrow and feed in the sediments.
As a result of these laboratory studies, a series of studies were undertaken
to examine the effects of bioturbation in the field. These efforts were devoted
to developing procedures to assess the importance of bioturbation in the field
as well as to make that assessment on particular rivers. This effort is ongoing.
To-date, research has focused on several small bayous in south Louisiana and on
several large rivers in the northeast and midwest.
Summary of Results:
Journal Articles on this Report : 4 Displayed | Download in RIS Format
|Other subproject views:||All 20 publications||8 publications in selected types||All 4 journal articles|
|Other center views:||All 392 publications||154 publications in selected types||All 106 journal articles|
||Mohanty S, Reible DD, Valsaraj KT, Thibodeaux LJ. A physical model for the simulation of bioturbation and its comparison to experiments with oligochaetes. Estuaries 1998;21(2):255-262.||
||Peters GM, Maher WA, Krikowa F, Roach AC, Jeswani HK, Barford JP, Gomes VG, Reible DD. Selenium in sediments, pore waters and benthic infauna of Lake Macquarie, New South Wales, Australia. Marine Environmental Research 1999;47(5):491-508.||
||Reible DD, Popov V, Valsaraj KT, Thibodeaux LJ, Lin F, Dikshit M, Todaro MA, Fleeger JW. Contaminant fluxes from sediment due to tubificid oligochaete bioturbation. Water Research 1996;30(3):704-714.||
||Thibodeaux LJ, Valsaraj KT, Reible DD. Bioturbation-driven transport of hydrophobic organic contaminants from bed sediment. Environmental Engineering Science 2001;18(4):215-223.||
Supplemental Keywords:bioturbation, contaminated sediments, and fate and transport., RFA, Scientific Discipline, Waste, Water, Ecosystem Protection/Environmental Exposure & Risk, Chemical Engineering, Contaminated Sediments, Environmental Chemistry, Fate & Transport, Analytical Chemistry, Hazardous Waste, Ecology and Ecosystems, Hazardous, Environmental Engineering, environmental technology, sediment treatment, hazardous waste management, hazardous waste treatment, risk assessment, fate and transport, contaminated marine sediment, soil and groundwater remediation, biodegradation, contaminated sediment, kinetics, chemical contaminants, contaminated soil, bioremediation of soils, marine sediments, remediation, chemical kinetics, hydrology, biotransformation, currents, anaerobic biotransformation, extraction of metals, bioturbation, technology transfer, heavy metals, bioremediation, aquifer fate and treatment, technical outreach
Progress and Final Reports:Original Abstract
Main Center Abstract and Reports:R825513 HSRC (1989) - South and Southwest HSRC
Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R825513C001 Sediment Resuspension and Contaminant Transport in an Estuary.
R825513C002 Contaminant Transport Across Cohesive Sediment Interfaces.
R825513C003 Mobilization and Fate of Inorganic Contaminant due to Resuspension of Cohesive Sediment.
R825513C004 Source Identification, Transformation, and Transport Processes of N-, O- and S- Containing Organic Chemicals in Wetland and Upland Sediments.
R825513C005 Mobility and Transport of Radium from Sediment and Waste Pits.
R825513C006 Anaerobic Biodegradation of 2,4,6-Trinitrotoluene and Other Nitroaromatic Compounds by Clostridium Acetobutylicum.
R825513C007 Investigation on the Fate and Biotransformation of Hexachlorobutadiene and Chlorobenzenes in a Sediment-Water Estuarine System
R825513C008 An Investigation of Chemical Transport from Contaminated Sediments through Porous Containment Structures
R825513C009 Evaluation of Placement and Effectiveness of Sediment Caps
R825513C010 Coupled Biological and Physicochemical Bed-Sediment Processes
R825513C011 Pollutant Fluxes to Aquatic Systems via Coupled Biological and Physicochemical Bed-Sediment Processes
R825513C012 Controls on Metals Partitioning in Contaminated Sediments
R825513C013 Phytoremediation of TNT Contaminated Soil and Groundwaters
R825513C014 Sediment-Based Remediation of Hazardous Substances at a Contaminated Military Base
R825513C015 Effect of Natural Dynamic Changes on Pollutant-Sediment Interaction
R825513C016 Desorption of Nonpolar Organic Pollutants from Historically Contaminated Sediments and Dredged Materials
R825513C017 Modeling Air Emissions of Organic Compounds from Contaminated Sediments and Dredged Materials title change in last year to "Long-term Release of Pollutants from Contaminated Sediment Dredged Material"
R825513C018 Development of an Integrated Optic Interferometer for In-Situ Monitoring of Volatile Hydrocarbons
R825513C019 Bioremediation of Contaminated Sediments and Dredged Material
R825513C020 Bioremediation of Sediments Contaminated with Polyaromatic Hydrocarbons
R825513C021 Role of Particles in Mobilizing Hazardous Chemicals in Urban Runoff
R825513C022 Particle Transport and Deposit Morphology at the Sediment/Water Interface
R825513C023 Uptake of Metal Ions from Aqueous Solutions by Sediments
R825513C024 Bioavailability of Desorption Resistant Hydrocarbons in Sediment-Water Systems.
R825513C025 Interactive Roles of Microbial and Spartina Populations in Mercury Methylation Processes in Bioremediation of Contaminated Sediments in Salt-Marsh Systems
R825513C026 Evaluation of Physical-Chemical Methods for Rapid Assessment of the Bioavailability of Moderately Polar Compounds in Sediments
R825513C027 Freshwater Bioturbators in Riverine Sediments as Enhancers of Contaminant Release
R825513C028 Characterization of Laguna Madre Contaminated Sediments.
R825513C029 The Role of Competitive Adsorption of Suspended Sediments in Determining Partitioning and Colloidal Stability.
R825513C030 Remediation of TNT-Contaminated Soil by Cyanobacterial Mat.
R825513C031 Experimental and Detailed Mathematical Modeling of Diffusion of Contaminants in Fluids
R825513C033 Application of Biotechnology in Bioremediation of Contaminated Sediments
R825513C034 Characterization of PAH's Degrading Bacteria in Coastal Sediments
R825513C035 Dynamic Aspects of Metal Speciation in the Miami River Sediments in Relation to Particle Size Distribution of Chemical Heterogeneity