Bioremediation of Sediments Contaminated with Polyaromatic Hydrocarbons
EPA Grant Number: R825513C020Subproject: this is subproject number 020 , 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: D. Reible, Danny
Title: Bioremediation of Sediments Contaminated with Polyaromatic Hydrocarbons
Investigators: Ward, C. Herb , Hughes, J. B.
Institution: Rice University
EPA Project Officer: Manty, Dale
Project Period: January 1, 1995 through January 1, 1997
Project Amount: Refer to main center abstract for funding details.
RFA: Hazardous Substance Research Centers - HSRC (1989)
Research Category: Hazardous Substance Research Centers
Description:
Objective:The research in this study focuses on requirements for application of bioremediation technology for cleanup of PAH contaminated sediments. In this project we examined the factors that control the design, operation, and effectiveness of sediment bioremediation processes. Specifically, the following were investigated;
1) Extent of treatment possible with highly contaminated, aged sediments (as
a function of PAH type, bioavailability, and microbial diversity/genotype).
2) Microbial and physical-chemical parameters that control degradation of
high molecular weight PAHs.
3) Optimization of slurry reactor operation (for
example, mixing and/or aeration rates, bioaugmentation, and surfactants to
increase bioavailability).
4) Use of a solid-phase oxygen source as a
pretreatment to prevent volatile organic carbon emissions when highly reduced
anaerobic sediments are aerated for PAH bioremediation.
PAH Biodegradation in Highly Contaminated Sediments
Initial studies
focused on the degradation of PAHs in highly contaminated sediments from Utica
Harbor (Utica, NY). These sediments (supplied by the Niagra Mohawk Power
Company) were contaminated over 70 years ago during the operation of a coal
gasification plant, and contain total PAH concentrations as high as 7,000 mg/kg
(primarily 2-,3-, and 4-ring compounds). Hence, the contaminants should be
highly sorbed and bioavailability should limit both the rate and extent of
contaminant biodegradation. These studies will be conducted in small slurry
reactors (200ml). Initial experiments addressed rates and extent of degradation
achieved under "ideal"laboratory conditions. Additional experiments using these
sediments were conducted to investigate adaptation and selection (population
shifts) of PAH-degrading organisms during the treatment process.
Parameters that Control Biodegradation of High Molecular Weight PAHs
These
studies focused on the effects of multiple contaminants on degradation patterns
in slurry reactors. Possible effects include co-oxidation and sequential
utilization. Experiments used sediments prepared in-house with defined mixtures
(two to four PAHs), and will focus on the influence of 2- and 3-ring PAHs on the
degradation of 4- and 5-ring PAHs. Abiotic controls were maintained for all
studies using HgCl2 (250 mg/L), and all experiments were conducted at least in
duplicate. Initial studies were conducted in a matrix design with sediments
contaminated with known levels of PAHs. To avoid volatilization losses, sealed
systems were used with adequate headspace to ensure aerobic conditions.
Optimization of Slurry Reactors to Enhance Rates and Extent of Biodegradation
while Minimizing Volatilization
A laboratory scale slurry reactor was
constructed that was capable of controlling DO and mixing intensities, and
equipped with on-line monitoring of CO2 production and hydrocarbon traps.
Reactors were constructed to control gas flow rates (either at preset constant
rates or to maintain a constant DO in the reactor) and mixed with variable speed
high torque mixers. Initial studies focused on control of gas flow rates to
minimize stripping losses. Experiments were conducted under various air flow
strategies (constant rate, constant DO) while monitoring biodegradation rates on
volatilization losses. Biodegradation rates were quantified by CO2 evolution and
extractions of sediment samples. The possible effects of bioaugmentation on
slurry reactor performance were also be studied. Bioaugmentation may be
effective for high molecular weight PAHs if population shifts are essential to
their degradation.
ORC Control of VOC Emissions from Bioreactors
In previous experiments we
found that the initial oxygen demand of anaerobic sediments can be met by
aeration and by the addition of hydrogen peroxide. Large amounts of hydrogen
peroxide are often required, but hydrogen peroxide at high concentrations is
toxic to bacteria (Fiorenza, 1992) and may adversely affect subsequent sediment
bioremediation. A new solid metal peroxide may offer a solution to the VOC
problem if it can be formulated to the special requirements of bioreactors. The
Oxygen Release Compound (ORC) is a magnesium peroxide and breaks down when
hydrated to yield oxygen and magnesium hydroxide (milk of magnesia). The parent
chemical and the end products are non-toxic and can be disposed without
regulatory concern. Experiments to meet the objective of VOC control from
disturbed sediments involved a sequential series of experiments to determine the formulation and application methods best suited for use with bioreactors.
Publications have been submitted on this subproject: View all 17 publications for this subproject | View all 427 publications for this center
Journal Articles:Journal Articles have been submitted on this subproject: View all 7 journal articles for this subproject | View all 114 journal articles for this center
Supplemental Keywords:bioavailability, volatile organics, and remediation. , Water, Scientific Discipline, Waste, RFA, Chemical Engineering, Analytical Chemistry, Hazardous Waste, Environmental Engineering, Environmental Chemistry, Contaminated Sediments, Hazardous, Ecology and Ecosystems, Bioremediation, remediation, risk assessment, PAHs, decontamination of soil, biodegradation, biotransformation, risk management, extraction of metals, soil and groundwater remediation, waste mixtures, contaminated sediment, slurry reactors, metal compounds, anaerobic biotransformation, environmental technology, CERCLA, contaminants in soil, contaminated soils, hazardous waste management, contaminated soil, bioremediation of soils, hazardous waste treatment, sediment treatment, technology transfer, chemical contaminants
Progress and Final Reports:
Final Report
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