Stochastic Framework for Addressing Chemical Partitioning and Bioavailability in Contaminated Sediment Assessment and Management

Abstract Sediment contaminated with metals, persistent toxic organics and nutrients represents a significant concern throughout the Great Lakes. The highest levels of sediment-associated contaminants and some of the worst manifestations of their resultant problems are found in the urban-industrial harbours, embayments and river mouths. These “Areas of Concern” require complete problem definition and remediation of all impaired uses. However, our ability to fully remediate contaminated sediments in these nearshore areas is limited by the availability of proven technology, adequate assessment data and suitable restoration goals. All of these requirements are currently in the research, development and demonstration phases. Each of these is discussed in the context of their technical problems and further research needs and development directions are indicated.

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Sediment Management: Ecological and Ecotoxicological Effects Must Direct Actions

Water Quality Research Journal ◽

10.2166/wqrj.2001.022 ◽

2001 ◽

Vol 36 (3) ◽

pp. 367-376 ◽

Cited By ~ 1

Author(s):

Gail Krantzberg ◽

Michael A. Zarull ◽

John H. Hartig

Keyword(s):

Action Plan ◽

Management Strategies ◽

Data Interpretation ◽

Sediment Management ◽

Biological Information ◽

Sediment Chemistry ◽

Contaminated Sediment ◽

International Joint Commission ◽

Sediment Assessment ◽

Beneficial Uses

Abstract The need for guidance on the bioassessment and management of contaminated sediment has been articulated by Remedial Action Plan practitioners, the International Joint Commission, scientists, and managers in many jurisdictions. Encouragingly, a convergence of opinion, on what constitutes a comprehensive sediment assessment, is beginning. However, there continues to be a need for methods to interpret and integrate multiple pieces of information on sediment chemistry, biological information from field monitoring and laboratory sediment bioassessment in an ecologically meaningful way. This paper recommends an approach to comprehensive sediment bioassessment that is driven by the need to rehabilitate “beneficial uses” as described in the Great Lakes Water Quality Agreement. The paper also highlights advances in data interpretation that are facilitating he development of sediment management strategies.

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Measured and Modelled Chlorinated Contaminant Distributions in the St. Clair River Water

Water Quality Research Journal ◽

10.2166/wqrj.1986.029 ◽

1986 ◽

Vol 21 (3) ◽

pp. 332-343 ◽

Cited By ~ 4

Author(s):

C.H. Chan ◽

Y.L. Lau ◽

B.G. Oliver

Keyword(s):

River Water ◽

Suspended Sediment ◽

Water Samples ◽

Concentration Distribution ◽

Suspended Solids ◽

Industrial Area ◽

Concentration Profiles ◽

Detroit River ◽

Chemical Partitioning ◽

Transverse Mixing

Abstract The concentration distribution of hexachlorobutadiene (HCBD), pentachloro-benzene (QCB), hexachlorobenzene (HCB) and octachlorostyrene (OCS) in water samples from transects across the upper and lower St. Clair River and the upper Detroit River were determined on four occasions in 1985. The data show a plume of these contaminants from the Sarnia industrial area. The fluxes and concentration profiles of the contaminants at Port Lambton have been modelled success fully using a simple transverse mixing model. A study on the chemical partitioning between the “dissolved” and “suspended sediment” phases shows that an important contaminant fraction is carried in the river by the suspended solids, particularly for lipophilie compounds such as HCB and OCS,

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Sequential risk mitigation and the role of natural recovery in contaminated sediment projects

Water Science & Technology ◽

10.2166/wst.1998.0769 ◽

1998 ◽

Vol 37 (6-7) ◽

pp. 331-336 ◽

Cited By ~ 3

Author(s):

Stephen Garbaciak ◽

Philip Spadaro ◽

Todd Thornburg ◽

Richard Fox

Keyword(s):

Lower Cost ◽

Risk Mitigation ◽

Management Strategies ◽

Source Control ◽

Contaminated Sediment ◽

Practical Observation ◽

Ecosystem Recovery ◽

Natural Recovery ◽

Natural Processes

Sequential risk mitigation approaches the remediation of contaminated sediments in three phases designed to: (1) immediately reduce the ecological and human health risks associated with high levels of contamination, using methods such as the confinement or capping of high-risk materials; (2) reduce the risks associated with moderate levels of pollution to a minimum, on a less urgent schedule and at a lower cost; and (3) address areas of limited contamination through a combination of natural recovery and enhanced natural recovery (to aid or speed those natural processes). Natural recovery, the reduction of contaminant concentrations through natural processes, is based on the practical observation that overall ecosystem recovery appears to be largely a function of time. Sediment decomposition and the mixing of new and old sediments by bottom-dwelling organisms can both contribute to reduced contaminant concentrations. Knowledge of these processes--sediment decomposition, sediment mixing by bottom-dwelling organisms, and chemical residence time is critical in the development of appropriate ecosystem recovery and waste management strategies. Evaluations to support natural recovery predictions are designed to collect and evaluate information necessary to determine whether surface sediment chemical concentrations, with adequate source control, will reach the cleanup standards within a ten-year period.

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