|
Characterization of Contaminated Sediments for Remediation
Projects in Hamilton Harbour
Alex J. Zeman, Environment Canada, National Water Research
Institute, Burlington, Canada
Timothy S. Patterson, Environment Canada, National Water
Research Institute, Burlington, Canada
Development of Concentration Thresholds for
the Hudson River PCBs Residuals Performance Standard
Claire Hunt, TAMS Consultants, an Earth Tech Co., Bloomfield,
NJ
Ed Garvey, TAMS Consultants, an Earth Tech Co., Bloomfield,
NJ
Jonathan Butcher, Tetra Tech, Inc., Research Triangle Park, NC
Alison Hess, Hudson River PCBs Site, USEPA Region 2, New
York, NY
Don Hayes, The University of Utah, Salt
Lake City, UT
Len Warner, Malcolm Pirnie, Inc., White Plains, NY
Bruce Fidler, Malcolm Pirnie, Inc., Fair Lawn, NJ
A
Spatially-Explicit Probabilistic Approach to Evaluating
and Assessing Human and Ecological Risks Associated with
PCB-Contaminated Sediments
Katherine von Stackelberg, Menzie-Cura & Associates,
Inc., Winchester, MA
Donna Vorhees, Menzie-Cura & Associates, Inc.,
Winchester, MA
Jerome Cura, Menzie-Cura
& Associates, Inc., Winchester, MA
An
Assessment and Remediation of the Fox River: A Case Study
Edward K. Lynch, PE, Wisconsin Department of
Natural Resources, Madison, WI
Mark Velleux, PE,
Colorado State University, Fort Collins, CO
Overview of Sediment Remediation of Tannery
Waste Contamination in Tannery Bay, White Lake, Michigan
Alisa A. Williams, DLZ Michigan, Inc., Lansing, MI
Garth R. Colvin, DLZ Michigan, Inc., Lansing, MI
Fred Pezeshk, DLZ Michigan, Inc., Lansing, MI
Curtis G. Roebuck, DLZ Michigan, Inc., Lansing, MI
In-Pile
Thermal Desorption of SVOCs in Riverine Sediments: in the
Barge or on the Bank
Ralph Baker, TerraTherm, Inc., Fitchburg, MA
Gorm Heron, Ph.D., TerraTherm, Inc., Bakersfield,
CA
John LaChance, TerraTherm, Inc., Fitchburg, MA
Optimizing River Cleanup Planning:
Balancing PCB Exposure Risks and Remediation
David Ludwig, BBL Sciences, Annapolis, MD
Stephen P. Truchon, BBL Sciences, New Bedford, MA
Helder J. Costa, BBL Sciences,
New Bedford, MA
Characterization of Contaminated Sediments
for Remediation Projects in Hamilton Harbour
Alex J. Zeman, Environment Canada, Naional Water Research
Institute, 867 Lakeshore Road, P.O. Box 5050, Burlington,
Ontario L7R 4A6, Canada, Tel: 905-336-4882, Fax:
905-336-6430, Email: Alex.Zeman@ec.gc.ca
Timothy S. Patterson, Environment Canada, National Water
Research Institute, 867 Lakeshore Road, P.O. Box 5050,
Burlington, Ontario L7R 4A6, Canada, Tel: 905-336-4454, Fax:
905-336-6430, Email: Tim.Patterson@cciw.ca
Hamilton Harbour is located on the western
end of Lake Ontario and has an area of approximately 31
square kilometers. The harbour has been designated by the
International Joint Commission (IJC) as one of the 42
Areas of Concern (AOCs) within the Great Lakes. Most
fine-grained sediments in the harbour exceed sediment
quality guidelines at the severe effect level due to
contamination both by metals and organic compounds such as
PAHs and PCBs. Current investigations are concentrated on
two areas of the harbour called Randle Reef and Windermere
Arm. The Randle Reef “hot spot” contains the most
highly contaminated sediment for PAH concentrations in the
harbour. Extensive information on sediment physical and
chemical properties was collected by coring and offshore
boreholes. Bioassays were carried out to determine
sediment toxicity. A range of remediation alternatives has
been considered, including removal and ex-situ treatment.
The current preferred alternative is an engineered
containment facility (ECF), which will contain in-situ
contaminated sediments within the footprint of the
structure. In addition, dredged sediment from other
contaminated sites in the harbour will be placed in the
ECF. Windermere Arm is a 50-ha narrow channel situated in
the southeast portion of the harbour. Contamination in
Windermere Arm is not as severe as that found in Randle
Reef. Recent sediment surveys in the area, however,
yielded higher PCB values in surficial sediments than
previously reported. Sediments in Windermere Arm are also
subject to considerable physical disturbance due to
extensive ship traffic. For this reason, historical
sediment contamination occurring in deeper sediments has
also to be considered as a potential risk to the aquatic
environment.
Development of Concentration Thresholds for
the Hudson River PCBs Residuals Performance Standard
Claire Hunt, B.E., TAMS Consultants, an Earth Tech Co., 300
Broadacres Drive, Bloomfield, NJ 07003, Tel: 973-338-6680,
Email: Claire.Hunt@earthtech.com
Ed Garvey, Ph.D., TAMS Consultants, an Earth Tech Co., 300
Broadacres Drive, Bloomfield, NJ 07003, Tel: 973-338-6680,
Email: Ed.Garvey@earthtech.com
Jonathan Butcher,
Ph.D., P.H., Tetra Tech, Inc., P.O. Box 14409, Cape Fear
Building, Suite 105, 3200 Chapel Hill-Nelson Highway,
Research Triangle Park, NC
27709, Tel: 919-485-8278 ext103, Email: jon.butcher@tetratech.com
Alison Hess,
M.S., C.P.G., Project Manager, Hudson River PCBs Site, USEPA
Region 2, 290 Broadway, 19th Floor, New York, NY 10007-1866, Tel: 212 637-3959, Email: hess.alison@epa.gov
Don Hayes,
Ph.D., The University of Utah, Salt
Lake City, UT 84112, Tel: 801-581-7110, Email: hayes@civil.utah.edu
Len Warner, B.S., Malcolm Pirnie, Inc., 104 Corporate Park
Dr., White Plains, NY 10602-0751, Tel: 914-694-2100,
Email: lwarner@pirnie.com
Bruce Fidler, M.S., P.E., Malcolm Pirnie, Inc., 17-17 Route
208 North, 2nd Floor, Fair Lawn, NJ 07410, Tel:
201-797-7400, Email: bfidler@pirnie.com
In 2002, USEPA issued the landmark decision to remediate the
Hudson River PCB site that extends 40 miles north of
Albany, NY by dredging the contaminated sediments. As part
of this precedent setting project, USEPA required three
engineering performance standards for productivity,
resuspension and residuals. USEPA has since developed
draft performance standards that are currently undergoing
peer review. This paper describes the development of
concentration limits established for the residual
performance standard.
The record of decision for this site established a goal of 1
mg/kg Tri+ PCBs residual concentration following inventory
removal. Experience from other dredging projects indicates
that this level of residual contamination is achievable,
but a degree of variability in the residual concentration
is to be expected with some areas of higher concentrations
likely. Areas of elevated concentration are often
associated with difficult subbottom conditions. The
standard was developed to allow for some areas of higher
concentrations as long as the overall average
concentration remained at or below 1 mg/kg Tri+ PCB, by
setting upper bound limits on average and individual point
concentrations.
The dredging residual concentrations from several sites were
analyzed to estimate the upper bound limits. The limits
were calculated from the upper confidence limit on the
mean and upper prediction limit. As there is no single
correct means of estimating these values for the
performance standard from non-site specific data, a weight
of evidence approach was adopted. The site residual
results had different concentration levels depending on
the goals set for the remediation and the site conditions.
For these results to be related the remedial goal of
another project three approaches were taken: a ratio of
the mean to the upper limit of the data sets; substitution
into the equations describing the threshold concentrations
assuming the data are lognormal; and using substitution
assuming that the data are neither normal or lognormal
(nonparametric). Results of the analysis showed that the
threshold levels for these methods were largely
consistent.
A
Spatially-Explicit Probabilistic Approach to Evaluating
and Assessing Human and Ecological Risks Associated with
PCB-Contaminated Sediments
Katherine
von Stackelberg, Menzie-Cura & Associates, Inc., 8
Winchester Place, Suite 202, Winchester, MA
01890, Tel: 781-782-6146, Fax: 781-756-1610, Email:
kvon@menziecura.co
Donna Vorhees, Menzie-Cura & Associates,
Inc., 8 Winchester Place, Suite 202, Winchester, MA
01890, Tel: 781-782-6143, Fax: 781-756-1610, Email:
dvorhees@menziecura.com
Jerome Cura, Menzie-Cura & Associates, Inc., 8
Winchester Place, Suite 202, Winchester, MA
01890, Tel: 781-782-6122, Fax: 781-756-1610, Email:
jcura@menziecura.com
We
present the development of a spatially-explicit
probabilistic aquatic food-web model, FishRand-Migration.
This model was originally developed for the Hudson
River RI/FS. Since then, with support from the Army Corps of Engineers,
the model has been modified to incorporate the ability to
specify spatial patterns of chemical concentrations
relative to fish migration and foraging characteristics.
The model is fully probabilistic and allows users
to specify uncertain or variable distributions instead of
point estimates for model parameters. The model predicts population distributions of time-varying
concentrations of hydrophobic contaminants with associated
uncertainty for each population fractile.
We present ways in which these results can be used
to support human health and ecological risk assessments.
Often, bioaccumulation modeling relies on point
estimate site use factors. FishRand-Migration provides more detailed and refined
predictions of chemical concentrations in aquatic biota
from which seasonal patterns in uptake can be discerned,
as well as relationships between potential risks and
hazards and the spatial distribution of contamination.
We will also discuss required model inputs for
application to other river systems.
An
Assessment and Remediation of the Fox River: A Case Study
Edward
K. Lynch, PE, Wisconsin Department of Natural Resources,
Bureau for Remediation and Redevelopment, 101 S. Webster
Street, Madison, WI 53707, Tel: 608-266-3084,
Fax:
608-267-7646, Email: edward.lynch@dnr.state.wi.us
Mark
Velleux, PE, Doctoral Student, Department
of Civil Engineering, A211 Engineering Research Center,
Colorado State University, Fort Collins, CO, Email:
mvelleux@engr.colostate.edu
In
October 2001, the EPA and the Wisconsin Department of
Natural Resources (WDNR) issued a Proposed Plan for
addressing PCB contamination of the Lower Fox River and
Green Bay. Development of the Proposed Plan and the
selection of a remedy were the end result of an extensive
evaluation process consistent with EPA guidelines for
CERCLA projects in accordance with the federal National
Contingency Plan (NCP). Subsequent to the Proposed Plan,
two Records of Decision (RODs) were issued. The remedy
selection process used was also consistent with NRC
recommendations and other EPA guidance regarding the
management of PCB-contaminated sediment sites. In addition
to a site-specific Remedial Investigation and Feasibility
Study (RI/FS), selection of the proposed remedy was based
on consideration of information provided by numerous
supporting studies, tools, and public comments. Each of
these supporting efforts contributed to the remedy
evaluation process by providing a wide spectrum of
analyses that consider the full range of possible outcomes
for each remediation alternative. The types of supporting
efforts contributing to the development of the Proposed
Plan include: field studies delineating the extent and
distribution of PCB in water, sediment, and fish; human
health and ecological risk assessments; analyses of the
spatial and temporal PCB concentration trends in sediment
and fish; contaminated sediment depth and sediment bed
stability; site-specific chemical transport and biota
modeling; sediment remediation evaluation and
demonstration projects; and public input into the remedy
selection process.
When
collectively considered with the RI/FS for the site, these
tools: 1) clearly demonstrate the need to remediate Lower
Fox River contaminated sediments; 2) show that technology
exists to implement the selected remedy; and 3) provide an
understanding of what may be reasonably expected after the
remedy is implemented. Overviews of the supporting studies
contributing to the remedy evaluation process as well as
discussion of the remedy selection process are presented
in two white papers attached to the RODs. These white
papers conclude with brief, operable unit (OU)-specific
summaries of the selected remedy to restore the
environmental quality of the river and bay. The selected
remedy is further described in the RODs for the site.
Overview of Sediment Remediation of Tannery
Waste Contamination in Tannery Bay, White Lake, Michigan
Alisa A. Williams, P.E., DLZ Michigan, Inc., 1425 Keystone
Ave., Lansing, MI 48911, Tel: 517-393-6800, Fax:
517-282-9280, Email: awilliams@dlz.com
Garth R. Colvin, P.E., DLZ Michigan, Inc., 1425 Keystone
Ave., Lansing, MI 48911, Tel: 517-393-6800, Fax:
517-282-9280, Email: gcolvin@dlz.com
Fred Pezeshk, P.E., S.E., DLZ Michigan, Inc., 1425 Keystone
Ave., Lansing, MI 48911. Tel:
517-393-6800, Fax: 517-282-9280, Email: fpezeshk@dlz.com
Curtis G. Roebuck, C.P.G., C.P., DLZ Michigan, Inc., 1425
Keystone Ave., Lansing, MI 48911, Tel: 517-393-6800, Fax:
517-282-9280, Email: croebuck@dlz.com
White Lake is listed as an U.S. Environmental Protection
Agency Great Lakes Area of Concern, because of beneficial
use impairments. Tannery
Bay is located in the northeast portion of White Lake, and
is adjacent to the former Whitehall Leather Company.
Historic contamination from former industrial
activities at the site, including dumping of leather
scraps and discharge of process wastewater containing
heavy metals into Tannery Bay, contributed to the
degradation of water and sediment quality in White Lake.
State resolutions and public involvement prompted the timely
cleanup of Tannery Bay.
Through Clean Michigan Initiative funding and
consent judgment with the responsible party, sediment
containing tannery wastes was dredged from Tannery Bay in
2002 and 2003. The
environmental dredge design was based on sediment sampling
and analyses information collected by the U.S. Army Corps
of Engineers and Michigan Department of Environmental
Quality. The
criteria used to determine if sediment was adversely
impacted included the presence of aesthetic indicators
(hide, hair, or burgundy discoloration) and/or elevated
chromium or arsenic concentrations, which were determined
to be indicative of tannery wastes.
Sediment removal was performed with hydraulic and mechanical
dredging equipment. Hydraulically
dredged sediment was dewatered through belt filter
presses, and liquid in mechanically dredged sediment was
bound using an absorbent polymer.
All dewatered sediment and debris was disposed of
at a municipal waste landfill.
Monitoring and engineering controls, including
turbidity monitoring and installation of a double silt
curtain system, were implemented to ensure that dredging
activities were conducted in compliance with permit
requirements and did not affect other areas of White Lake.
Sediment verification sampling was performed to
assure that remediation objects were met.
After completion of dredging activities, sand and
riprap were placed along Tannery Bay shoreline areas, to
create a gently sloping littoral zone and provide
shoreline stabilization.
In-Pile
Thermal Desorption of SVOCs in Riverine Sediments: in the
Barge or
on
the Bank
Ralph S. Baker,
TerraTherm, Inc., 356 Broad St., Fitchburg, MA 01420, Tel:
978-343-0300, Fax:
978-343-2727
Gorm Heron, Ph.D., TerraTherm, Inc., 10554 Round
Mountain Road, Bakersfield,
CA 93308, Tel:
661-387-0610, Fax: 978-343-2727
John
LaChance, TerraTherm, Inc., 356 Broad St., Fitchburg, MA
01420, Tel: 978-343-0300, Fax: 978-343-2727
Current overall treatment
costs for contaminated dredged river sediments can be as
high as $500-700 per ton. This presentation focuses on an
innovative thermal treatment method, which is likely to be
highly effective at full-scale costs of less than one
third of this cost ($130-300 per ton depending on total
volume).
TerraTherm’s
IPTD technology is an ex-situ version of In-Situ Thermal
Destruction (ISTD), by which TerraTherm utilizes
simultaneous application of thermal conduction heating and
vacuum to treat contaminated soil and sediment without
excavation. The
contaminated solids are placed in piles, interlayered with
heater pipes and vapor extraction screens. If necessary,
the contaminated material will be dewatered prior to
treatment. Each
pile would contain a bermed area with a vapor-and
liquid-tight bottom and sides, a leachate collection
system, heater elements and vapor extraction wells
distributed throughout the spoils. A vapor cap is placed
over the piles to contain fugitive emissions and allow for
application of a vacuum to the pile. For monitoring
purposes, thermocouples and pressure transducers are
inserted at select locations to document heating progress
and vacuum conditions, respectively.
The piles are then heated and
treated using electrical heaters, which bring the
temperature up to the target, typically around 300 to 350 oC,
depending on the nature of the contaminants. The applied
heat volatilizes both water and organic contaminants
within the soil, enabling them to be carried in the air
stream toward vacuum extraction wells for destruction
within the soil and transfer of the remaining vapor to an
air quality control (AQC) unit.
It is anticipated that >95% of the contaminant
mass will be destroyed in the heated soil.
Remedial results (post-treatment soil
concentrations) depend both on the target temperature and
the duration of treatment, with non-detect being a
practical goal if necessary.
This presentation will
focus on the IPTD technology application for Semi-Volatile
Organics such as PCB and chloro-benzenes.
Treatability study results and full-scale treatment
concepts will be presented, including:
- Laboratory treatability studies showing removal efficiencies for
different contaminants and treatment temperatures.
- Drum-scale testing of
remedial efficiency.
- Results of a field-scale pilot demonstration of IPTD for SVOC treatment.
- Conceptual design of
full-scale IPTD treatment of dredged river
sediments/spoils.
- Discussion of treatment
of dredged spoils in the barges used to transport the
material.
- Estimated treatment
costs as a function of the treated volume.
Finally, our
recommendations for further analysis of the opportunities
and most appropriate applications of the IPTD technology
will be presented.
Optimizing
River Cleanup Planning:
Balancing PCB Exposure Risks and Remediation
David Ludwig, BBL Sciences, 326 First Street, Suite 200,
Annapolis, MD 21403,
Tel: 410-295-1205, Fax: 410-295-1225, Email: dfl@bbl-inc.com
Stephen P. Truchon, BBL Sciences, 174 Union Street, Suite 300, New Bedford, MA
02740, Tel: 508-992-3609,
Fax: 508-997-5520, Email: stp@bbl-inc.com
Helder J. Costa, BBL Sciences, 174 Union Street, Suite
300, New Bedford, MA
02740, Tel: 508-992-3609,
Fax: 508-997-5520, Email: hjc@bbl-inc.com
Managing PCB-contaminated sediments in rivers has long posed
a decision dilemma—how can multiple sources of
environmental impact (from chemical exposure, destructive
remediation, and baseline impairments) be compared
objectively and effectively?
This dilemma resulted in the preparation and
publication of a “A Risk Management Strategy for
PCB-Contaminated Sediments” by the National Research
Council in 2001. This
Strategy Report provides a useful framework for
identifying issues and background information regarding
the nature of exposure and remediation impacts.
However, it does not offer guidelines or
comparative assessment techniques for decision making in
specific cases. In
this presentation, we present an integrated management
decision process specifically intended for application in
small to medium sized, urbanized and industrialized
waterways. The
process emphasizes comparative risk analysis, and
incorporates chemical exposures, remedial disruption,
baseline impairments, and post-remediation restoration as
explicit elements. Each
element is presented in the context of a holistic,
watershed and riparian ecosystem based analysis, whose
overall objective is to maximize environmental quality. The analysis presumes that a balance of human use and
ecological service flows is desirable, and that some
management flexibility is available in both the riparian
corridor and the waterway proper.
The approach emphasizes phased decision making and
staged implementation, with monitoring and adaptive
management throughout the program.
By incorporating adaptive feedback in a robust
analytical structure, a technically sound and
scientifically credible foundation can be established for
the effective management of waterways in human landscapes.
Top
|
