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Conference on Dredged Material Management: Options and Environmental
Considerations
December 3-6, 2000
Massachusetts Institute of Technology

Fishing vessels at dock in Woods Hole, MA |
New England and Mid Atlantic States Sea Grant College Programs and
collaborators convened a conference on management of contaminated
dredged materials. Topics included scientific and technical issues
related to nearshore disposal choices, financial and legal issues
and policy implications. Three concurrent one-day workshops were held
on different topics regarding dredged material disposal management.
The purpose of the conference was to review scientific and technical
information and practical experience on the use of confined aquatic
disposal cells, confined disposal facilities, and nearshore beneficial
use disposal options as practical ways of managing contaminated sediment
disposal. The six main topics of the conference were:
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Confined Aquatic Disposal Cell
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Beneficial Uses
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Confined Disposal Facilities
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Risk Assessment
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Policy and Management of Contaminated Sediments
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Tools and Techniques
Three parallel workshops, consisting of lectures
and discussion. Summaries of two of the three workshops follow:
Use of Confined Aquatic Disposal Cells to Manage Sediments in Ports
and Harbors
Options for disposal of contaminated sediment are limited by public perception,
regulations, technical uncertainties and cost. The option selected for
the Boston Harbor Navigation Improvement Project involves confined aquatic
disposal (CAD) cells-constructed in-channel, filled with contaminated
sediments dredged from nearby, and capped with clean sand. Although CAD
cells appear technically and environmentally promising, accurate placement
of dredged and capping materials depends on imprived understanding of
several issues (e.g. geotechnical strength of recently placed sediments
and their ability to support a cap, sediment resuspension and transport,
contaminant fluxes through capping material, response of benthic communities
to temporally and spatially varying sediment properties, optimal site
selection, evaluation of environmental effectiveness). These topics and
others were discussed with reference to field experiences in Boston Harbor
and elsewhere, along with supporting theoretical and laboratory studies,
and presented in a context for general application elsewhere.
Sediment Toxicity and Risk Assessment Tools: Where are We and Where
Should We be Going?
The Use of Dredged Materials for Erosion Control and Wetlands Creation
Restoring damaged coastal ecosystems is a national priority since many
vital areas providing essential ecosystem services to society have been
damaged by overdevelopment. Hundreds of cubic kilometers of sediment are
dredged each year for commercial and recreational purposes and discharged
into land based disposal facilities or into the nation's oceans, estuaries,
rivers and lakes. Dredged material containment facilities are nearing
fill capacity or are already full; and designating new containment sites
creates numerous social and economic conflicts. Dredged material is a
very valuable resource for environmental enhancement projects such as
restoring or establishing new wetlands, and for beach restoration and
stabilization. Accelerating investigations of the environmental uses of
dredged material on coastal areas may help stem the predicted impacts
from rises and falls in sea level and make traditional disposal of dredged
materials unnecessary. However, few studies have addressed the ecological
aspects of dredged materials engineering, especially vital information
on how materials placement is critical for creating ecologically functional
environments. Interdisciplinary research is urgently needed to evaluate
dredged materials, to select proper site selection and elevations, and
to complete economic, social and legal assessments in order to generate
new policies and procedures for the accelerated use of dredged material
for environmental and social benefits.
Abstracts
Abstracts from most of the presentations are
available online in both html and PDF
format. Clicking on the respective links will take you to a page containing
a list of abstracts in alphabetical order by the primary author's last
name. The abstracts available in PDF format are arranged in groups of
approximately ten abstracts per PDF document. A document containing all
of the abstracts is also available in PDF format..
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