x>EPA
Office of Water
Washington, DC 20004
EPA 842-R-16-002
2016
2013 National Ocean Dumping Site
  Monitoring Assessment Report
              May 2016

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2013 National Ocean Dumping Site Monitoring Assessment Report
Executive Summary

In the United States, uncontaminated dredged material is the primary material (in terms of
volume) disposed into the ocean today. Dredged material is sediment excavated or otherwise
removed from the bottoms of the navigable waters of the United States to maintain navigation
channels and docks. Other materials disposed in the ocean include fish wastes, vessels, and
human remains for burial at sea.

Under the Marine Protection, Research, and Sanctuaries Act (MPRSA), U.S. Environmental
Protection Agency (EPA) is responsible for designating and managing ocean disposal sites for
the permitted disposal of materials. In Fiscal Year 2013 (FY 2013), EPA managed 95
designated ocean disposal sites located off the U.S. Atlantic, Gulf and Pacific Coasts,  and in the
Caribbean, Hawaii and the Pacific Islands. All but one  of these sites is for the disposal of
uncontaminated sediment (dredged material) removed from our nation's waterways to support a
network of coastal ports and harbors for commercial, transportation, national defense and
recreational purposes. In FY 2013, marine transportation contributed more than $59 billion and
420,000 jobs to the US economy (National Ocean Economics Program, 2016).

EPA designates ocean disposal sites in areas that minimize the impact of ocean dumping on
various amenities, such as fisheries, coral reefs, and endangered species; minimize
interferences with other uses of the ocean,  particularly navigation and fisheries; and support the
cost-effective maintenance of the ports and harbors vital to the  nation's economy and security.

Once designated, management of ocean disposal sites is necessary to ensure that disposal
activities will not unreasonably degrade or endanger human health, welfare, the marine
environment, or economic potentialities. Effective management of ocean disposal sites prevents
chemical contamination of sediments, physical obstructions, and damage to tourist attractions
like beaches and coral reefs.

Monitoring is a key component of management of ocean disposal sites. EPA monitors the
environment within and around each ocean site to verify that permitted disposal does not cause
unanticipated or significant adverse effects and that terms of MPRSA permits are met. While
EPA's testing procedures and ocean dumping criteria effectively used to evaluate sediment that
is proposed for ocean disposal, monitoring at ocean disposal sites is necessary to ensure that
the marine environment is not being adversely impacted by disposal activities.

This national report presents EPA's ocean dumping monitoring  activities in FY 2013. EPA
conducted 13 surveys at 20 ocean disposal sites offshore from  Puerto Rico, Virginia, South
Carolina, Florida, Texas, Hawaii, and Oregon. This report summarizes each survey's
objective(s), activities, conclusions, and recommended environmental management actions.

As part of the FY 2013 surveys, EPA scientists employed a wide range of well-established
monitoring techniques, including sampling marine sediment, conducting dive operations and fish
trawls, measuring waves and currents, and collecting video and still underwater imagery. These
are scientifically sound techniques widely accepted in the scientific community. EPA assessed
changes in biological community conditions, chemical  contaminant levels  in sediment and biota,
water quality, and sediment grain size. At some sites, EPA evaluated fate and transport of
material after disposal to determine if the material moved in unanticipated ways and had the
potential to adversely impact other uses of the ocean,  such as nearby fisheries.

EPA confirmed that environmentally acceptable conditions  were met at 14 of 20 ocean disposal
sites surveyed in FY 2013. At these 14 sites, EPA determined that dredged material disposal
had not adversely impacted the ecosystem, permitted  disposal  could continue, and no further

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2013 National Ocean Dumping Site Monitoring Assessment Report
action was needed. At three of the six other ocean disposal sites surveyed (Sabine-Neches
Sites 3 and 4, and Mouth of the Columbia River Deep Water Site), further investigation of the
site conditions is necessary to determine if any changes in management practices are needed.
And at the last three ocean disposal sites (Charleston, Jacksonville, and Chetco), EPA
determined that modifications to the boundaries and/or permitted use of the site are necessary
to sustain environmentally acceptable conditions for future management of the sites. Findings at
these six sites are discussed in the following paragraphs.

Surveys at Sabine-Neches Sites 3 and 4 and Mouth of the Columbia River Deep Water Site
showed that additional investigation is necessary. Monitoring at Sabine-Neches Sites 3 and 4
(TX) revealed hotspots of high metal concentrations in sediments. High metal concentrations in
sediments can cause adverse effects to organisms that live on, in, or near the seafloor. These
metals can also magnify as they are transferred up the food chain, ultimately impacting higher
trophic level species, such as large marine predators and humans. EPA plans to conduct
additional surveys at these sites focused on the hotspots to identify if any management actions
are needed to prevent the occurrence of adverse effects. From the survey at the Mouth of the
Columbia River (OR), EPA found that the migration of dredged material after disposal was
different than anticipated. EPA plans to conduct additional studies at the site to explore the fate
and transport of material after  disposal and ensure that it will not impact marine life or navigation
in this area.

Finally, surveys at Charleston, Jacksonville, and Chetco led EPA to determine that, in order to
sustain environmentally acceptable conditions for future management of the sites, modifications
to site boundaries and/or permitted use were necessary. EPA conducted a wave and current
study at Charleston (SC) to better understand the fate and transport (and potential impacts) of a
significant increase in dredged material disposal planned for the site. This material will come
from a project to deepen Charleston Harbor to accommodate post-Panamax ships. Based on
the data and information evaluated to date, EPA currently anticipates that the material is likely to
move outside of site boundaries and that the disposal zone within the site should be enlarged to
prevent adverse  environmental impacts offsite. At Jacksonville (FL), EPA analyzed sediment
profile imagery, which demonstrates that dredged material had migrated off the site to the north
and south. As a result, EPA plans to restrict the release zone at the disposal site farther from
site boundaries to prevent impact to the benthic communities outside of site boundaries. Lastly,
EPA (with USAGE) conducted a survey at Chetco (OR) to evaluate whether dredged material
disposal was impacting nearby rocky reef habitat. EPA determined that, while disposal activities
had not yet adversely impacted reef communities, adjustments to site usage are warranted to
safeguard this valuable habitat resource.
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                              TABLE OF CONTENTS

      1.0 Introduction	5
      2.0 Objectives	7
      3.0 Summary of Monitoring Surveys	8
         3.1 Region 2 -Arecibo, Mayaguez, and San Juan ODMDSs, Puerto Rico	9
         3.2 Region 3-Dam NeckODMDS, Virginia	9
         3.3 Region 4 - Charleston Harbor ODMDS, South Carolina	11
         3.4 Region 4 - Fernandina Beach ODMDS, Florida	12
         3.5 Region 4-Jacksonville ODMDS, Florida	13
         3.6 Region 4- Pensacola Offshore ODMDS, Florida	15
         3.7 Region 4 - Tampa Bay ODMDS, Florida	15
         3.8 Region 6 - Sabine-Neches ODMDSs 1, 2, 3, and 4, Texas	16
         3.9 Region 9-HiloODMDS, Hawaii	19
         3.10 Region 9 - South Oahu ODMDS, Hawaii	21
         3.11 Region 10-Chetco ODMDS, Oregon	23
         3.12 Region 10-Coos Bay Sites F and H, Oregon	24
         3.13 Region 10-Coquille ODMDS, Oregon	26
         3.14 Region 10-Mouth of the Columbia River Deep Water Site, Oregon	27
      4.0 Conclusion	28
      5.0 Acknowledgements	29
      6.0 References	29
      7.0 Appendix - Site Characteristics of Disposal Sites Surveys in FY2013	30
                          LIST OF FIGURES AND TABLES

Figure 1. Locations of the 20 Disposal Sites surveyed in 2013	7
Figure 2. Map of 2013 SPI Dredged Material Thickness, Jacksonville ODMDS	14
Figure 3. Map for Sites 1-4 and Reference Sites, Sabine-Neches ODMDS	18
Figure 4. Sediment grain size distribution for Sites 1-4 in 1980 and 2013, Sabine-Neches
           ODMDS	19

Table 1. Summary of Sediment Physical and Chemical Analyses, South Oahu ODMDS	23
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                        ACRONYMS AND ABBREVIATIONS

ADCP        acoustic Doppler current profilers
CTD         conductivity, temperature, depth
DDT         dichlorodiphenyltrichloroethane
DWS         deep water site
EA           environmental assessment
EIS          environmental impact statement
EPA         United States Environmental Protection Agency
ERL         effects range low
ERM         effects range median
MCR         Mouth of the Columbia River
MPRSA      Marine Protection, Research, and Sanctuaries Act
NOAA        National Oceanic and Atmospheric Administration
ODMDS      Ocean Dredged Material Disposal Site
OSV         ocean survey vessel
PAH         polycyclic aromatic hydrocarbon
PCB         polychlorinated biphenyl
PVP         plan view photography
ROV         remotely operated vehicle
R/V          research vessel
SEF         sediment evaluation framework
SL           screening level
SMAR        site monitoring assessment report
SMMP        site management and monitoring plan
SPI          sediment profile imaging
SQGs        sediment quality guidelines
USAGE      United States Army Corps of Engineers
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1.0 Introduction

The Marine Protection, Research, and Sanctuaries Act (MPRSA), sometimes referred to as the
Ocean Dumping Act, regulates the dumping and transportation for the purpose of dumping of
any material into ocean waters. Generally, ocean dumping cannot occur unless a federal permit
is issued under the MPRSA.

Under the MPRSA, U.S. Environmental Protection Agency (EPA) established environmental
criteria for the evaluation of all permit applications. EPA also issues the ocean dumping permits
for all materials other than dredged material. In the case of dredged material, U.S. Army Corps
of Engineers (USAGE) issues the ocean dumping  permits (or, in the case of federal projects,
authorizes ocean dumping of dredged material) using EPA's environmental criteria. All MPRSA
permits and federal projects  involving the ocean dumping of dredged material are subject to
EPA review and concurrence. All dredged material proposed for ocean dumping  must be tested
using published testing guidance and must meet the published dumping criteria.

EPA is responsible for designating ocean disposal sites under the MPRSA. To minimize the
adverse impacts of ocean dumping on  human health and the marine environment, EPA
designates  sites based on environmental studies of the proposed site, environmental studies of
regions adjacent to the proposed site, and historical knowledge of the impact of disposal on
areas having similar in physical, chemical, and biological characteristics. EPA carefully
considers specific criteria (published at 40 CFR 228.5 and 229.6) as part of a site designation
evaluation to ensure that the site selected for designation will not likely cause significant
adverse impacts to the surrounding marine environment. EPA analyzes these impacts through
environmental assessments  or environmental impact statements for site designations. In
general, EPA designates sites only in areas where ocean dumping will not have a significant
impact on various amenities, such as fisheries, coral reefs, and endangered species.

EPA is also responsible for managing all ocean disposal sites designated under the MPRSA.
EPA management helps ensure that disposal activities will not unreasonably degrade or
endanger the marine environment, human health, welfare, or economic potentialities.
Management of the ocean disposal sites involves:

   •  regulating the times, quantity and characteristics of the material dumped at the site;

   •  establishing disposal controls, conditions and requirements to avoid and minimize
      potential impacts to the marine environment; and

   •  monitoring the site and surrounding environment to verify that unanticipated or
      significant adverse effects are not occurring from past or continued use of the ocean
      disposal site and that terms of the MPRSA permit are met.

All designated sites are required to have a site management and monitoring plan (SMMP). EPA,
in conjunction with USAGE, develops an SMMP for each ocean disposal site. Each SMMP
includes, but may not be limited to:

   •  a baseline assessment of site conditions;

   •  a program for monitoring the site;

   •  special management conditions or practices to be implemented at each site that are
      necessary for protection of the environment;

   •  consideration of the quantity of disposed materials, and the presence, nature, and
      bioavailability of the contaminants in the material;
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   •   consideration of the anticipated long-term use of the site; and

   •   a schedule for review and revision of the SMMP.

A key component of the SMMP is the monitoring program. The monitoring program for each site
is designed to assess current environmental conditions and trends at and around the disposal
site, evaluate disposal impact to ensure that the dumped material is  being adequately tested
and there are no unexpected impacts, evaluate movement and deposition of the dumped
material to determine whether or how to modify site use, and support SMMP development and
updates. EPA typically evaluates environmental impact at a site by comparing current conditions
to the conditions at the time of designation (baseline conditions) and before recent disposals.
Reference (control) areas, which are close to the disposal site but that do not receive disposed
materials, are also used to assess the impact of disposal.  Guidelines for ocean disposal site
baseline and trend assessment surveys are set forth in 40 CFR 228.13. EPA  conducts these
surveys using scientifically sound monitoring techniques widely accepted in the scientific
community.

Fiscal Year 2013

In fiscal year (FY) 2013, EPA  Regional Offices managed 95 ocean disposal sites off the U.S.
Atlantic, Gulf of Mexico, and Pacific Coasts,  Hawaii, and near U.S. territories  in the Caribbean
Sea and Pacific Ocean. All but one of the 95 ocean disposal sites are designated for the
disposal of dredged material permitted or authorized under the MPRSA. These sites are often
located offshore of major ports, harbors, and marinas nationwide.

During FY 2013, EPA scientists conducted 13 oceanographic surveys at 20 ocean dredged
material disposal sites (ODMDSs), located in six of the seven EPA coastal Regions (Figure 1).
EPA conducted these monitoring surveys using vessels accessed through contracts and
through interagency agreements with National Oceanic and Atmospheric Administration (NOAA)
and USAGE, as well as vessels owned and operated  by EPA Regions.
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2013 National Ocean Dumping Site Monitoring Assessment Report
  Mouth of ColumMa
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                 Figure 1. Locations of the 20 Disposal Sites surveyed in 2013
2.0 Objectives
This national report serves as a comprehensive summary of the 2013 ODMDS monitoring
surveys. Specifically, the report summarizes survey objectives, activities, results, and
environmental management decisions as reported in the Site Monitoring Assessment Reports
(SMARs) prepared by EPA  Regions. In 2013, EPA Regions submitted 13 SMARs for the 20
ODMDSs surveyed:
    •   San Juan, Puerto Rico (Region 2);
    •   Arecibo, Puerto Rico (Region 2);
    •   Mayaguez, Puerto Rico (Region 2);
    •   Dam Neck, Virginia (Region 3);
    •   Charleston, South Carolina (Region 4);
    •   Fernandina Beach, Florida (Region 4);
    •   Jacksonville, Florida (Region 4);
    •   Pensacola Offshore, Florida (Region 4);
    •   Tampa, Florida (Region 4);
    •   Sabine-Neches Site 1, Site 2, Site 3, and Site 4, Texas (Region 6);
    •   South Oahu, Hawaii (Region 9);
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   •   Hilo, Hawaii (Region 9);

   •   Chetco, Oregon (Region 10);

   •   Coos Bay Site F and Site H, Oregon, (Region 10);

   •   Coquille River, Oregon (Region 10);

   •   Mouth of the Columbia River Deep Water Site, Oregon (Region 10).

3.0 Summary of Monitoring  Surveys

In 2013, EPA funded and conducted monitoring surveys to assess ocean disposal site
conditions, support designations of new ocean disposal sites, support modifications in the size
or use of existing ocean disposal sites, and provide information for updates of SMMPs at
existing ocean disposal sites.  These surveys employed  a wide range of acceptable monitoring
approaches including collecting  sediment grab samples, conducting dive operations and fish
trawls, collecting wave and current measurements, and obtaining video and still underwater
imagery. Depending on the purpose of each specific survey and the information needed, the
surveys used techniques that varied from simple and straightforward to complicated and highly
technical. Using this information, EPA assessed the physical, chemical, and biological
conditions of the sediment and water in and around the disposal site to determine if conditions
at the site are acceptable or if disposal is causing unacceptable impacts. In some cases, EPA
evaluated the spatial extent (footprint) of dredged material to better understand if the dredged
material is behaving as expected following disposal at a site; i.e., remaining within the bounds of
the site or moving outside of a site. Sediment grain size was commonly assessed to detect the
presence of dredged material, which is typically fine-grained, organic-rich sediment. The
presence of macroinfaunal organisms, or organisms inhabiting sediments that are large enough
to be seen with the naked eye, was the most common biological condition assessed in these
surveys.

EPA commonly compares contaminant concentrations in site sediments to sediment quality
guidelines (SQGs) to evaluate the potential for dredged material disposed at a site to have an
impact on the benthic communities at or near disposal sites. SQGs are informal benchmarks
used to relate chemical concentrations in sediments to the potential  toxicity to benthic or aquatic
organisms. SQGs are used to estimate the toxicity of sediments, to identify areas and specific
chemicals of concern, and to direct further investigations (Long and  MacDonald,  1998). Different
SQGs have been established by various entities at the national and  regional levels.  Many EPA
Regions rely on Effects Range Low (ERL) and Effects Range Medium (ERM) national SQGs
developed by NOAA (NOAA,  1999) to assess conditions at ocean disposal sites. Chemical
concentrations below the NOAA ERL cause adverse effects infrequently, while chemical
concentration above the NOAA  ERM are likely to cause adverse effects.

The quantity and distribution of samples collected in each of the EPA monitoring surveys vary
considerably. A number of factors cause the differences in sampling in the FY 2013 surveys.
For example, if past surveys and historical data from an ODMDS have shown a high variance in
the measurements taken at that site, EPA typically collects additional samples to adequately
characterize the site. If existing data shows the site to be consistently homogenous over many
years, sampling need not be so  rigorous. Sampling may also be influenced by other factors
including, but not limited to, the specific objectives of the survey and the scope of the
investigation. The protocols for sample collection are designed not only to be scientifically
sound, but also to be logistically and financially practical.
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A summary of FY 2013 survey objectives, activities, and results, as well as the environmental
management decisions made following these surveys is presented below, by EPA Region.

       3.1 Region 2 - Arecibo, Mayaguez, and San Juan ODMDSs, Puerto Rico

Region 2 monitored three ODMDSs (Arecibo, Mayaguez, and San Juan), located along the
north and west coasts of Puerto Rico. The Region conducted this  monitoring survey in February
2013 aboard the NOAA research vessel (R/V) Nancy Foster. The  objective of this survey was to
assess the quality of previously identified hard bottom habitats along and adjacent to transit
routes used by dredging scows from Arecibo, Mayaguez, and San Juan harbors to the disposal
sites. Region 2 sought to determine if coral is present along these routes or at these ocean
disposal sites. Seven coral species found near Puerto Rico are listed as threatened under the
Endangered Species Act.

Region 2 used a remotely operated vehicle (ROV) and drop camera to obtain video and still
imagery.  The Region also collected multibeam bathymetry data of the disposal sites, transit
routes, and surrounding areas of similar depth. EPA collected images of both hard and soft
bottom habitats within the disposal sites and hard bottom habitats adjacent to and along transit
routes.

From the images collected in this FY 2013 survey, EPA identified  that the habitat within the
disposal sites, along the transit routes, or directly adjacent to transit  routes  appeared to be low
quality (low organism abundance) with no coral presence. EPA scientists identified higher
quality hard bottom habitats that support corals (that is,  with high organism abundance,
including corals) far outside the transit routes between Arecibo and Mayaguez harbors and the
disposal sites.

Region 2, using multibeam imagery, identified sheer vertical walls at the continental shelf  edge,
located inshore of the disposal sites. These vertical walls likely inhibit the shoreward transport of
dredged material disposed at the sites. Although these data do not relate to assessing habitat
quality at the disposal sites, they do provide insight regarding the  extent of  the disposal footprint
at these sites.

Based on the data collected in the survey, Region 2 confirmed that the transit routes for scows
to transport dredged material to the Arecibo, Mayaguez, and San  Juan ODMDSs from the
primary harbor for which the ODMDS was designated (Arecibo, Mayaguez, and San Juan
harbors) do not threaten valuable hard-bottom habitats. These findings confirmed the route
restrictions already in place in the Arecibo ODMDS SMMP, supported the lack of restrictions in
the San Juan ODMDS SMMP, and will be used to modify the Mayaguez  ODMDS SMMP to
include route restrictions when active use resumes at that site.

       3.2 Region 3 - Dam Neck ODMDS, Virginia

Region 3 monitored the Dam Neck ODMDS, located offshore from Virginia Beach, VA. The
Region conducted this monitoring survey in July 2013 aboard the  NOAA R/V Nancy Foster. The
objective of this survey was to compare environmental conditions  at Dam Neck ODMDS to a
control site to evaluate whether and the extent to which disposal of dredged material at the
ODMDS was causing significant adverse impacts.

Region 3 scientists collected sediment samples from 50 stations, including  25 stations within the
disposal site and 25 stations at the control site. Sediment samples were analyzed for benthic
community status, metal concentrations, and grain size. Region 3 statistically analyzed the data
to determine if there was a significant difference between the conditions at  the disposal site and


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the conditions at the control site. Region 3 then compared the results of this analysis to the
results of biennial surveys conducted at the Dam Neck ODMDS between 2005 and 2013.

Region 3 found statistically significant differences between the benthic communities at the Dam
Neck ODMDS and the control site in 2013. Benthic communities typically are assessed using
three parameters: richness (the number of species in a community), evenness (the relative
abundance of each species in a community), and diversity (a combination of richness and
evenness). Benthic community diversity and richness were determined to be significantly lower
at the disposal site compared to the control site. These determinations are consistent with
previous studies conducted to evaluate the disposal site since 2005. Benthic community
evenness was also lower at the disposal site in 2013, but the difference was not significant.
These benthic community differences seen at both sites are within the level of disturbance
expected due to disposal operations and, therefore, are not a concern for Region 3.

Data and information comparing the Dam Neck ODMDS and the control site indicate that
conditions in these two areas are similar in sediment grain size but significantly different in some
metal concentrations. Sediment grain size at both sites was predominately sand (>95%).
Copper, nickel, lead, and zinc concentrations were found to be statistically different at the
disposal site compared to the control site. The concentrations of these metals have been
consistently and relatively higher at the disposal site compared to the control site since 2005.
However, these metals are naturally occurring,  and although differences were statistically
different,  these metal concentrations  are very low when compared to the NOAA ERL/ERM.
Sediment chemical concentrations above the NOAA ERL, but below the NOAA ERM, are not
likely to be harmful to benthic organisms, but are considered by EPA, in the context of other
evidence, when making environmental management decisions. These metal concentrations
remain low enough to not trigger any management decisions. Additionally, low to undetectable
concentrations of other metals, including cadmium, mercury, and silver, have been measured at
both sites since 2005.

Based on the data collected in the survey, Region 3 confirmed that environmentally acceptable
conditions are being met at the site and the Region does not recommend any changes to the
site's SMMP at this time. From information collected during this survey, Region 3 found
statistically significant differences in benthic community parameters (diversity and richness) and
four metal concentrations (copper,  nickel, lead, and zinc) between Dam Neck ODMDS and its
control site. The differences seen in benthic communities at both sites are within the level of
disturbance expected from disposal operations at the site. Therefore, Region 3 does not believe
these differences are a cause of concern. Additionally, although some metal concentrations
were statistically different between Dam  Neck ODMDS and its control  site, these concentrations
fall below the NOAA ERL/ERM, and therefore, Region 3 does not expect that these
concentrations are toxic to benthic organisms.

Region 3 used a portion of the 2013 Dam Neck ODMDS survey to collect samples in support of
non-Ocean Dumping EPA programs.  Given the uncertainties associated with conducting
oceanographic surveys, EPA scientists typically include extra time in their survey plans to
accommodate potential delays due to severe weather. During July 2013 survey, the weather
conditions were favorable; therefore,  Region 3 used the extra time built into the survey to collect
additional water quality samples. These samples were used to support the Region's long-term
monitoring effort to analyze trends  in  nutrient data along the Mid-Atlantic Bight. EPA also used
these samples, for the first time, to develop a baseline for future evaluation of ocean
acidification.

Ocean acidification is a significant stressor for calcifying  organisms because it affects the ability
of these organisms to grow and maintain aragonite-based structure (e.g., shells, reefs) when Q


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is low. Ocean acidification evaluation is relevant to EPA's work because of the potential
ecological and economic impacts caused by this phenomenon, as well as its use as an indicator
of climate change. Region 3 deployed a rosette sampler, equipped with conductivity,
temperature, and depth (CTD) probe, to obtain seawater samples for the measurement of total
alkalinity (TA) and dissolved inorganic carbon (DIG). These parameters provide insight on a
marine system's buffer intensity, which is a measure of the ability of seawater to resist
appreciable pH changes. Due to the inter-relationship of carbonate parameters, measurement
of TA and DIG allows the calculation of the partial  pressure of dissolved carbon dioxide (pCC>2)
and aragonite saturation state (Q).

Based on the data collected in the survey, Region 3 plans to continue this monitoring effort to
better understand the condition of these Bays and the effects of ocean acidification on near
coastal and open ocean water bodies. Water sampling results identified areas in the Mid-
Atlantic Bight that were experiencing low Q and high pCC>2 concentrations. For transects
conducted from the mouth of the Chesapeake Bay to 100 kilometers seaward, low Q and high
pCC>2 conditions were observed from the mouth of the  Bay to 30 kilometers seaward, and in
pockets between 50 and  100  kilometers seaward.  For transects conducted from the mouth of
the Delaware Bay to 60 kilometers seaward, low Q was observed over the extent of the
transect. These observations  of low Q suggest that calcifying organisms (e.g.,  crabs, sea snails,
coral, etc.) in the monitoring area may be subject to acidification-related stress. The impact that
this stress would have on the  ability of these organisms to grow shell  could have a significant
effect on fisheries production.

       3.3 Region 4 - Charleston Harbor ODMDS, South  Carolina

Region 4 monitored the Charleston Harbor ODMDS, located offshore of Charleston, South
Carolina. The Region conducted the monitoring survey between  November 2012 and May 2014
aboard the 28-foot Parker, a Region 4 vessel, supported by Region 4 and USAGE funds. The
objective of this survey was to assess wave and current patterns and their impact on site
capacity. The Region anticipates a significant increase in the amount of dredged material to be
proposed for disposal at the Charleston Harbor ODMDS due to a project planned to deepen the
harbor to accommodate post-Panamax vessels. Region 4 plans to use the data in water quality
models to assess potential dispersion of dredged material after disposal at the ODMDS as well
as potential impacts on benthic communities. USAGE will also use the wave and current data to
evaluate beneficial use options for their Regional Sediment Management Program.

For this study, acoustic Doppler current profilers (ADCPs) were deployed a total of five times
inshore, within, and seaward of the Charleston Harbor ODMDS.  Deployments  lasted between
three and five months each. The ADCPs measured wave directionality, wave height, wave
period (time between waves), current directionality, and current velocity.

From the wave measurements, Region 4 identified differences between the waves at the three
survey locations. At the disposal site and offshore, waves originated from the east-southeast
with long wave periods of 4 to 11 seconds. Inshore, waves also had long periods of 5 to  13
seconds. Wave heights were  highest offshore and smallest inshore. In general, inshore and
offshore waves were highest in June (inshore= 0.8 m; offshore=  1.6 m) and within the disposal
site, waves were highest in November (1.2 m).

Currents in the vicinity of Charleston ODMDS were found to  have a significant tidal component.
The disposal site's currents flowed predominately  east and west. Currents flowed differently in
the northern inshore stations than in the southern  ones. In the north, currents flowed
predominately west-southwest. In the south, currents flowed north-northwest and east-
southeast. The offshore station did not have a dominant flow direction. Within the disposal site,


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there was a dominant offshore current during the summer months and an inshore current during
the winter months. Surface currents at the disposal site were almost twice as strong as near-
bottom currents at both stations. The average current magnitude was about 18 cm/sec. Two
distinct high and low tides per day were documented at the disposal site.

Region 4 plans to use the results of this survey to modify the existing disposal site. The wave
and current measurements collected in this study and the shallow depths in the vicinity of the
Charleston ODMDS suggest that the relatively large, long wave periods are likely to re-suspend
and redistribute bottom sediments frequently. As such, the large quantity of dredged material
that will be generated by the deepening of Charleston Harbor likely would be transported
outside of the Charleston ODMDS boundaries. The large quantities  of dredged material have
the potential to cause adverse impacts to benthic communities in a manner that was not
evaluated during the original site designation process. To accommodate the anticipated
increase  in dredged material disposal without causing unacceptable impacts, EPA will modify
the existing Charleston ODMDS by increasing the dredged material disposal zone (from 4 mi2 to
9.8 mi2).  By increasing the disposal zone, dredged material can be managed so that it does not
impact the benthic community outside of the zone. EPA will also modify the existing Charleston
ODMDS  by de-designating the area outside of the disposal zone (which decreases the overall
size of the ODMDS from 15.1 mi2 to 9.8 mi2). This de-designated area includes recently-
identified marine habitat. By decreasing the overall size of the site, this habitat will be protected
from the impact of dredged material disposal.

       3.4 Region 4 - Fernandina Beach ODMDS, Florida

Region 4 monitored the Fernandina Beach ODMDS, located  off the Atlantic coast of Florida.
The Region conducted this monitoring survey in conjunction with the Jacksonville ODMDS
survey in August 2013 aboard the NOAA R/V Nancy Foster. The primary objective of the survey
was to characterize and quantify the hard bottom habitat previously assessed within the
Fernandina Beach ODMDS. Hard bottom habitats provide substrate for attachment of sessile
organisms, as well as food and shelter for smaller fish and invertebrates. EPA compared the
hard bottom habitats, initially identified during a 2011 survey, to a natural hard bottom ledge
located outside the disposal site (reference area). Since identified, the hard bottom areas have
been avoided during disposal operations pending further analysis of the habitat.

In the 2013 study, an EPA dive team conducted habitat assessments at 20 stations, including
15 stations within the disposal site and five stations at the reference area. The habitat
assessments  included, but were not limited to, counts of the occurrences of fish,
macroinvertebrate, and live bottom cover at the assessment stations. Live bottoms occur when
animals form a dense layer of living creatures that completely covers the underlying hard
surface.

Region 4 found little difference between the hard bottom habitats within the disposal site and the
reference area. Both areas had an abundance offish, relief, and live cover.  Areas with little to
no relief tended to have fewer and smaller fish as well as fewer macroinvertebrates and  different
assemblages  of live cover. The reference area had higher fish biomass (larger fish) compared
to stations within the Fernandina Beach ODMDS. The highest fish abundances were identified
at stations within the Fernandina Beach ODMDS. The two most abundant fish species found
during this survey were the tomtate and black sea bass. The  black sea bass populations
exhibited the highest biomass and were observed at every station. The two stations within the
disposal site with the highest fish abundance also had the highest numbers of purple-spined sea
urchins, the most dominant macroinvertebrate observed. However, there did not appear to be a
relationship between the number of purple-spined sea urchins and the number offish. Although
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the reference area had the lowest number of purple-spined sea urchins observed, the reference
area also had the largest amount of live sessile colonies.

Based on the data collected in the survey, Region 4 confirmed that environmentally acceptable
conditions are being met at the site and the Region does not recommend any changes to the
site's SMMP at this time. Overall, Region 4 found very little difference between the live bottom
area surveyed within the Fernandina Beach ODMDS  and the naturally occurring hard bottom
areas outside the disposal site at the reference  area,  indicating that the habitat created by the
dredged material serves a similar ecological function  as nearby natural habitat. Region 4 plans
to share the results and coordinate with state and federal resource agency partners to
determine if additional studies or site management actions are needed. Examples of potential
site management actions could include but would not be limited to changes to the SMMP for the
Fernandina Beach ODMDS to support and maintain the continued protection of one or more of
the areas evaluated, further evaluation of the habitat,  or no further action. Region 4 also
anticipates using information collected in this survey to support management of rocky dredged
material disposal at ODMDSs across the Region.

      3.5 Region 4 - Jacksonville ODMDS, Florida

Region 4 monitored the Jacksonville ODMDS, located off the Atlantic coast of Florida. The
Region conducted this monitoring  survey in conjunction with the Fernandina Beach ODMDS
survey in August 2013 aboard the NOAA R/V Nancy  Foster. The objective of this survey was to
determine if dredged material disposed between 2010 and 2013 at the Jacksonville ODMDS
caused significant adverse impacts. Region 4 also sought to confirm the adequacy of site
management practices that limit the disposal zone to  500 feet inside of the site boundaries to
prevent the movement of dredged material offsite.

Region 4 collected sediment profile imagery (SPI) from 50 stations,  including 46 stations
distributed within and surrounding the disposal site and four stations at reference areas. This
information was used to analyze the dredged material fate and transport, sediment grain size,
and benthic infaunal communities. The 2013 survey results were compared to previous SPI
surveys  conducted prior to disposal activities (survey in late 2010 to early 2011) and during
disposal activities (survey in April 2012).

From the 2013 survey results,  the Region found that the dredged material footprint has
expanded beyond the disposal site's boundaries. The SPI showed the presence of dredged
material, more than 5 centimeters thick, well past the  southern boundary of the disposal site
(Figure 2). A thinner layer of dredged material was observed past the northern boundary of the
site in both the 2012 and 2013 SPI surveys (Figure 2). The orientation of the dredged material
footprint changed between 2012 and 2013. The movement and expansion of the footprint likely
resulted from both disposal of material after the 2012 survey and the influence of currents (EPA
and USAGE, 2007).

The 2013 SPI showed no significant differences in grain size and benthic communities within
the disposal site, surrounding the disposal site,  and at the reference areas. Most stations visited
primarily contained very fine sand, similar to the 2012 SPI survey results. In contrast, fine sand
was observed at most stations within the disposal site in the 2010-2011 SPI survey. In the 2013
survey, stage I was the most common benthic successional stage seen at sampled stations.
Stage I infauna are the first organisms to colonize the sediment surface following a disturbance.
The benthic communities observed around the periphery of the dredged material footprint in
2013 were more mature (stage II), than what was observed in the 2012 survey. The stage I and
stage II benthic communities seen at the stations in the 2013 SPI survey are typical of the
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benthic communities found in this part of the ocean and suggest that dredging has had a
minimal effect on benthic communities.

Based on the data collected in the survey, Region 4 plans to modify the SMMP to change the
release zone for ocean disposal, increasing the buffer of 500 feet to 1000 feet on the north and
south site boundaries in order to maintain the disposal foot boundary within the disposal site.
Region 4 would like  to contain the dredged material within the site to avoid any impact to offsite
benthic communities and concluded that the 500-foot buffer from the site boundary for the
disposal of dredged  material is not sufficient to prevent movement of material offsite. The 2013
SPI results indicate that dredged material extended past the north and south boundaries of the
site. Region 4 concluded that the dredged material has not adversely impacted the benthic
communities. Disposal activities have shifted the bottom sediments to be more fine-grained,
which support more  mature benthic communities.
         Soundings in feet MLLW
         55
            52
               46
47


S/S





fS
                        44
                  46
          50
                      47
            47
             45

                     48
         •Reported value is a minimum
DM Thickness (cm) DM Type

 • Not present   £ Unconsolidated Silt DM
 O 0.0-5.0

0 5.1 -10.0

(/O 10.1 -15.0      White Fine Sandy DM

x~x         |  | Disposal Site Boundary
                       Reworked DM

                       Unc. Silt & Reworked DM
                 DM Thickness
                 Interpolation

                 Interpreted Contour
                  — 1 cm
                 ^^— 5 cm
                  — '10 cm
                                                                 59
                                                    54
           Figure 2. Map of 2013 SPI Dredged Material Thickness, Jacksonville ODMDS
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       3.6 Region 4 - Pensacola Offshore ODMDS, Florida

Region 4 monitored the Pensacola Offshore ODMDS, located off the Gulf coast of Florida. The
Region conducted this monitoring survey in conjunction with the Tampa Bay ODMDS survey in
September 2013 aboard the NOAA R/V Nancy Foster. The objective of this survey was to
evaluate impacts of ocean disposal at the site on the marine environment.

Region 4 collected sediment samples from 12 stations distributed within and surrounding the
disposal site. The Region analyzed the samples for grain size, chemical contaminants, and
benthic infaunal community parameters. Region 4 also collected water quality samples from four
of those 12 stations (two within and two outside the site) from near surface and bottom waters
using water sampler with a CTD probe.

Analysis of water samples found that water quality was similar within and outside the site. No
toxic chemical constituents were found. All four stations sampled were nearly identical in
temperature, salinity, dissolved oxygen, and density. However, the analysis did indicate that the
disposal site has a poorly mixed water column, with warmer, fresher water at the surface and
cooler, more saline waters towards the bottom. Chemical analysis detected six metal
contaminants (arsenic, chromium, copper, lead, nickel, and zinc) in the water samples, but all
were below levels of concern, based on marine water quality criteria established by the Clean
Water Act. Region 4 uses this data to validate water column models that predict chemical
concentrations in the water column after dredged material disposal.

With the exception of two stations, PE11 and PE12, the stations sampled within and
surrounding the Pensacola Offshore ODMDS were generally biologically, physically, and
chemically similar. Most bottom sediments were predominantly sand (96.3- 99.9%). Sediments
at stations PE11 and PE12 averaged 64% sand and 36% fine-grains. Most stations had a very
low percent total organic carbon (<0.1%), while PE11 and PE12 had a higher percentage of
total organic carbon (1.25% and 0.56%, respectively). These two stations also had the lowest
percent solids of all the stations sampled.  Chemical analyses of the sediments revealed
detectable amounts of several contaminants, all of which were highest at either PE11 or PE12.
The contaminants detected, including metals, polycyclic aromatic hydrocarbon (PAHs), and
butyltins, were all below levels of concern. Most stations had healthy benthic infaunal
communities with similar taxa diversities including polychaetes (78.8- 87.9%), mollusks (6-
12%), and arthropods (0.4-7%). Only one  benthic infaunal species was observed at PE11 (a
polychaete) and PE12 (a brachiopod).

Based on their analysis of the data collected in the  survey, Region 4 confirmed that
environmentally acceptable conditions are being met at the site and does not recommend any
changes to the site's SMMP at this time. Region 4 found the benthic community structure to be
healthy and similar across 10 of the 12 stations surveyed, both within and surrounding the
disposal site. Region 4 concluded that recent disposal activity, which occurred less than eight
weeks prior to survey, affected stations PE11 and PE12 within the disposal zone more than the
other stations sampled. The effect of the disposal was indicated by the lower percent solids and
higher total organic carbon levels  present, which is typical of dredged material.  The two stations
were not located in proximity to one another, suggesting a patchy spatial distribution of dredged
material within the site. Region 4 attributed low benthic diversity at stations PE11 and PE12 to
insufficient recovery time after a recent disposal event.

       3.7 Region 4 - Tampa Bay ODMDS, Florida

Region 4 monitored the Tampa Bay ODMDS, located off the Gulf coast of Florida. The Region
conducted this monitoring survey in conjunction with the Pensacola Offshore ODMDS survey in


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September 2013 aboard the NOAA R/V Nancy Foster. The objective of this survey was to
evaluate the impact of disposal on the marine environment at Tampa Bay ODMDS.

Region 4 collected sediment samples from 12 stations, including 10 stations within the disposal
site and two stations surrounding the disposal site. Of the 10 stations within the site, six stations
were within the area in the northeast corner of the site where the Region currently directs users
to release dredged material (disposal zone). Water samples were collected from four of the 12
stations (two within and two outside the site) from near surface and bottom waters using a water
sampler with a CTD probe. Sediment samples were analyzed for grain size, chemical
contaminants, and benthic infaunal community parameters. Region 4 conducted statistical
analyses to determine if there were significant differences in water and sediment characteristics
between the stations within and surrounding the disposal site.

Analysis of the water samples  showed similar water quality within and outside the site and no
toxic chemical constituents. Nearly identical temperature, salinity, dissolved oxygen, and density
were observed in water samples collected from the four sampling stations. Region 4 found the
disposal site has a well-mixed  water column,  with no apparent layering (stratification). Chemical
analyses detected six different metal contaminants (arsenic, chromium, copper, lead, nickel,
and zinc) in the water samples. All metal contaminant concentrations were found to be below
levels of concern, based on marine water quality criteria established by the Clean Water Act.
Region 4 uses this data to validate water column models that predict chemical concentrations in
the water column after dredged material disposal.

The sediments sampled at the Tampa Bay ODMDS were, generally, chemically and physically
similar. Although not statistically significant, analysis showed that sediments from outside the
disposal zone had higher metal contaminant concentrations. Two stations outside the disposal
zone had arsenic exceedances of the NOAA  ERL (NOAA, 1999).  Sediment chemical
concentrations above the NOAA ERL, but below the NOAA ERM, are not likely to be harmful to
benthic organisms, but are considered by EPA, in the context of other evidence, when  making
environmental management decisions. All metal concentrations except zinc were highest at
stations outside of the disposal zone. Bottom sediments at all stations were predominantly sand
(73.4- 97.3%) and primarily solids (68.3- 82.4%).

Healthy, productive (and biologically similar) benthic infaunal communities were found  at all
stations sampled. Annelids dominated the benthic infaunal communities at 9 of 12 stations. EPA
Region 4 compared the benthic communities within and outside the disposal zone and found no
significant differences.

Based on the data collected in the survey, Region 4 confirmed that environmentally acceptable
conditions are being met at the site and does not recommend any changes to the site's SMMP
at this time. Region 4 determined that all stations had healthy, productive benthic infaunal
communities, with no significant differences found between stations within and  surrounding the
disposal site. Slight differences in benthic diversity among sites were attributed to differences in
sediment composition. Despite the variable percentages of sediment grain sizes observed in
this study, Region 4 found no distinctive pattern that could be attributed to the historical
placement of dredged material. Further, Region 4 found no statistically significant differences in
metal concentrations between  stations within the disposal zone and stations outside of the
disposal zone. Region 4 found no indication of adverse impacts to the marine environment.

      3.8 Region 6 - Sabine-Neches ODMDSs 1, 2, 3, and 4, Texas

Region 6 monitored the Sabine-Neches ODMDSs 1, 2, 3, and 4, located in the Gulf of  Mexico,
off the Texas-Louisiana border (Figure 3). This monitoring survey was conducted in September


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2013 aboard the NOAA R/V Manta. The objective of this survey was to collect data to assess
the overall environmental impact of past and recent disposal operations to the benthic infaunal
community and bottom sediments and determine if the disposal footprint has extended past the
sites' boundaries.

The Region collected SPI at 130 total stations distributed within and surrounding the four
disposal sites and two reference sites to analyze the dredged material footprint, sediment grain
size, and benthic infaunal community parameters. Region 6 collected sediment samples from 22
stations within the four ocean  disposal sites, 22 stations surrounding the ocean disposal sites,
and three stations at each of the two reference sites. These 50 sediment stations were a subset
of the 130 SPI stations. The sediment samples were analyzed for grain size, chemical
constituents, and benthic infaunal  community parameters. All stations within Sites 2 and 4 were
evenly distributed. Stations within Sites 1 and 3 were distributed between the areas used for a
2012 disposal event and the areas not used during the 2012 disposal event.

Region 6 compared the data from  this 2013 survey to data collected in previous surveys,
including 1979-1980 field surveys  and a 1995 baseline survey conducted at the four ODMDSs.
Region 6 also compared the 2013 survey data to pre-disposal dredged material sediment
testing results from 1993 to 2010,  as contained  in four contaminant assessment reports (1993,
1999, 2004, and 2010). In addition, the Region evaluated the sediment chemistry data against
the benchmarks set by NOAA (NOAA, 1999).

Physical analyses revealed various grain size distributions in the sampled areas. Areas within
Site 1 used for the 2012 disposal event had finer sediments compared to areas within the site
not used  in the 2012 disposal  event. Sediment samples from Site 2 were found to be dominated
by sand.  Sediment samples from Site 3 and Site 4 were found to be dominated by fine
sediments. Compared to data collected in 1980, grain size was found to have significantly
changed  at Sites 1 and 3, shifting to more fines; grain size was not found to have significantly
changed  at Sites 2 and 4 (Figure 4).

Region 6 compared sediment contamination results at the ODMDSs from 2013 to those
previously reported in sediment contaminant assessment reports for the  navigation channel, the
reference sites, and the ODMDSs  from 1993 to 2010. The concentrations of arsenic, nickel,
beryllium, silver, zinc, selenium, and barium from 2013 exceeded the historical maximums
within Sites 3 and 4. Sediment chemical analysis from the 2013 study found both arsenic and
nickel at levels of concern. The arsenic and nickel concentrations exceeded the NOAA ERL in
sediments collected within and surrounding Sites 3 and 4. Sediment chemical concentrations
above the NOAA ERL, but below the NOAA ERM, are not likely to be harmful to benthic
organisms, but are considered by  EPA, in the context of other evidence,  when making
environmental management decisions. Selenium and barium  concentrations in 2013 exceeded
the historical maximums at Sites 1 and 2.

Using SPI, Region 6 observed that the dredged material footprint centered over the disposal
sites and that the material extended beyond the boundaries of Sites 1, 3, and 4. Historic and
recent dredged material was observed beyond the boundaries at Sites 1, and only historic
dredged material beyond the boundaries at sites 3 and 4. Region 6 also reviewed the 2012
disposal records at Sites 1 and 3, and did  not find any indication that dredged material was
disposed beyond these ODMDS boundaries during 2012 disposal operations. (The Sabine-
Neches Sites 1,  2, 3, and 4 are dispersive by nature; that is, dredged material disposed at the
sites is being transported outside the site boundaries by the current.)
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         •-
                                                                    c_r
                           '
             "
                         .   .   "
    Legend



    |    |ODMDS


         Reference

         Area
Sabine-Neches ODMDS(s) & Reference Sites



        Basemap: NOAA RNC Mosaic (ESRI. NOAA)

          Produced by EPA Region 6. Dallas. TX
^*"*S
 SL\
                                                  I Miles
Ai^J
      '"i «oit0
           Figure 3. Map for Sites 1-4 and Reference Sites, Sabine-Neches ODMDS
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2013 National Ocean Dumping Site Monitoring Assessment Report
                    1980  2013

                      Sitel
 1980  2013

   Site 2

Gravel  BSand BSilt
1980  2013

  Site 3

• Clay
1980  2013

  Site 4
 Figure 4. Sediment grain size distribution for Sites 1-4 in 1980 and 2013, Sabine-Neches ODMDS

Region 6 observed similar benthic infaunal assemblages at Sites 1, 2, 3, and 4 and the
reference sites. Polychaete assemblages dominated the benthic communities at these sites.
The specific polychaete taxa that were found to be dominant (Mediomastus, Meredithia,
Paraprionospio, Prinospio, and Cossura) are very common in the Gulf of Mexico. Benthic
macroinfaunal assemblages at the sites fell into two broad groupings based on sediment type.
Taxa richness was typically greater at Sites 1 and 2 which were characterized by sandy or
sand/silt sediments compared to Sites 3 and 4 which were dominated primarily by fines. The
benthic community indices (Pielou, 1966), taxa richness and density, were not significantly
different within the disposal sites, surrounding the disposal sites, and at reference sites for three
of the four ODMDSs. For Site 3, taxa densities and richness at stations within the site where the
2012 disposal event occurred were found to be significantly higher than stations representing
areas within the site that were not used during the  2012 disposal event. Taxa richness at all
stations within and around Site 3 was significantly lower than taxa richness at the reference
sites.  Region  6 concluded that recent dredged material disposal at Sites 1 and 3 did not impact
benthic assemblages, because taxa richness and densities were higher at stations where
dredged material was placed during the 2012 disposal event.

Based on the data collected in the survey, Region 6 confirmed that environmentally acceptable
conditions are being met at the sites and does not  recommend any changes to the SMMPs at
this time. Region 6 determined that disposal activities have not adversely impacted the benthic
community at any of the ODMDSs. However, the source for the increased arsenic and nickel
concentrations observed in sediments is unknown  and warrants further investigation. To better
assess the extent of the disposal footprint, Region  6 plans to collect samples from stations
beyond the area of the 2013 survey during future surveys. Region 6 may also evaluate disposal
placement records prior to the 2012 disposal event for Site 4 to determine if the material has
naturally  migrated past the site boundary since placement or if the material was inadvertently
placed beyond the boundaries at the time of disposal.

       3.9 Region 9 - Hilo ODMDS, Hawaii

Region 9 monitored the Hilo ODMDS, located offshore of Hilo on the island of Hawaii. The
Region conducted this monitoring survey in conjunction with the South Oahu ODMDS survey in
June and July 2013 aboard the NOAA R/V Hi'ialakai. The objective of this survey was to assess
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the dredged material footprint at the Hilo ODMDS and identify if disposal activities were causing
adverse impacts to the marine environment.

Region 9 obtained SPI and sediment samples from stations extending radially in 8 directions
from the center of the site to outside of the site boundaries. Region 9 obtained SPI and plan
view photography (PVP) from 46 stations, including 15 stations within the disposal site and 31
stations surrounding the disposal site to identify the horizontal extent and thickness of the
dredged material. Region  9 used this information to identify eight sediment sampling stations
(four within the disposal site and four surrounding the disposal site) to further characterize the
seafloor. Sediment samples were analyzed for grain size, chemical constituents, and benthic
infaunal community parameters. SPI were also analyzed for sediment and benthic community
recolonization. Region 9 compared the results of the 2013 survey to the 1980 baseline
conditions when the site was originally designated, including comparison of the chemical
constituents concentrations to the applicable NOAA ERL (concentration below which adverse
effects seldom occur) and NOAA ERM (concentration above which adverse effects frequently
occur) limits (NOAA, 1999).

Dredged material was found beyond site boundaries and predictable changes to the sediments
and the benthic community had occurred. SPI showed dredged material was thickest at the
station located at the center of the site. The thickness of the dredged material decreased
towards the edges of the site, where dredged material was only 0.1 to 1.0 centimeters thick.
Outside the site, the dredged material was found to be either within this range of thickness or
only seen  in trace amounts. This is below the threshold of concern as defined by the EPA.
Stations within and surrounding the site were dominated by stage I on III benthic communities.
These communities are characterized by organisms present at the sediment surface (stage I)
and more  mature organisms present in burrows within the sediment (stage III). Stage I on III
communities indicate rapid recolonization after dredged material disposal and a well-established
infaunal community, suggesting no lasting long-term adverse impacts. The only station that did
not have a well-established benthic community was located at the center of the disposal site.
This station had the thickest layer of dredged material, which most likely altered its infaunal
community. The overall abundance of infaunal organisms was slightly higher at stations
surrounding the site than stations within. Crustaceans were more abundant within the disposal
site, while annelids, mollusks, and miscellaneous taxa were more abundant surrounding the
site. Despite these  differences, stations located within the disposal site were not statistically
different in terms of benthic abundance or diversity. Compared to the baseline data collected in
1980, the abundance of miscellaneous taxa decreased and the abundance of mollusks
increased. The bottom sediments at Hilo were variable and ranged from gravel to fine-grains.
More gravel and sand were observed within the disposal site and more fine sediments were
observed surrounding the site. The percentage of fine sediments and gravel within the disposal
site increased compared to the 1980 baseline.

The bulk chemistry data showed low, but variable,  concentrations of most chemical
constituents. At stations within and surrounding the disposal site, three metals (arsenic,
chromium, and copper) were found at concentrations above their NOAA ERL. Sediment
chemical concentrations above the NOAA ERL, but below the NOAA ERM, are not likely to be
harmful to benthic organisms, but are considered by EPA, in the context of other evidence,
when making environmental management decisions. Concentrations of these metals were
highest outside the disposal site. Region 9 compared the metal concentrations of cadmium,
copper, mercury, and lead to those recorded in the 1980 baseline.  Only copper concentrations
outside the disposal site were higher than concentrations recorded in the  1980 baseline.
Because these elevated concentrations were found outside and shoreward of the disposal site,
the increase could be due to other shore-side sources or historic "short-dumping" from disposal
scows before compliance  monitoring was implemented. Short-dumping is the disposal from

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scows before they reach the disposal zone. Nickel was the only chemical constituent that
exceeded its NOAA ERM. Nickel exceeded its NOAA ERM at all stations. Much of the
geomorphological character of the sediments in this area is related to the original volcanic
formation of the Hawaiian Islands, which are naturally elevated in nickel concentration.
Therefore, these nickel concentrations are not reason for concern. There were no exceedances
of the NOAA ERM for organic contaminants (dioxins, dichlorodiphenyltrichloroethanes (DDTs),
organotins, PAHs, and polychlorinated biphenyls (PCBs)) within or surrounding the disposal
site.

Based on the data collected in the survey, Region 9 confirmed that the environmentally
acceptable conditions are being met at the site and, at this time, does  not recommend any
changes to be incorporated during the upcoming update of the site's SMMP. From information
collected in this 2013 survey, Region  9 found that dredged material extended past site Hilo
ODMDS boundaries. Region 9 concluded that the presence of dredged material outside the Hilo
ODMDS is not due to recent ocean disposal activities,  but rather is likely due to its proximity to
historic disposal sites and lack of compliance monitoring prior to the 2000s which made
detection of short-dumps outside of the ODMDS boundaries difficult. Region 9 also found that
historic and recent dredged material disposal have not caused significant adverse impacts at
this site. Sediment chemistry and benthic communities within and outside the disposal site were
not statistically different. Differences between grain size, sediment chemistry, and benthic
community parameters observed during this survey and the site data collected in the 1980
survey are due to minor and localized physical changes. Region 9 determined that continued
use of the site should similarly result in no significant adverse effects.

      3.10 Region 9 - South Oahu ODMDS,  Hawaii

Region 9 monitored the South  Oahu ODMDS, located  offshore of Pearl Harbor on the island of
Oahu. Region 9 conducted this monitoring survey in conjunction with the Hilo ODMDS survey in
June and July 2013 aboard the NOAA R/V Hi'ialakai. A separate geophysical survey was
conducted aboard a separate vessel owned by Sea Engineering. The  objective of this survey
was to assess the overall impact of disposal operations and determine if the disposal footprint
extended past the site boundaries.

Region 9 collected images and sediment samples within and surrounding the disposal site.
Region 9 obtained SPI and PVP from 40 stations, including 16 stations within the disposal site
and 24 stations surrounding the disposal site to identify the horizontal  extent and thickness of
the dredged material. Region 9 used this information to select 10 sediment sampling stations
(five within the disposal site and five surrounding the disposal site) to further characterize the
seafloor. Sediment samples were analyzed for grain size, chemical constituents, and infaunal
community parameters. SPI were also analyzed for sediment parameters and benthic
community recolonization. Region 9 compared the survey results of the 2013 survey to 1980
baseline conditions when the site was originally designated, including  comparison of the
chemical constituent concentrations to the applicable NOAA ERL (concentration below which
adverse effects seldom occur)  and NOAA ERM  (concentration above which adverse effects
frequently occur) limits (NOAA, 1999).

Geophysical measurements were taken at the disposal site and surrounding areas using a high-
resolution sub-bottom seismic-reflection profiler. Using the results, including an estimated
overall dredged material volume based on a calculated average thickness, Region 9 evaluated
the results of the estimated cumulative volume of dredged material present  at the South Oahu
ODMDS relative to the volume of dredged material disposed at the site, based on USAGE
ocean disposal records.
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Survey results showed that dredged material was present well beyond the site boundary, but
this is not likely due to recent ocean disposal because the variation in grain size or benthic
communities present within or surrounding the site did not correlate with the patterns of current
ocean disposal of dredging projects using the site. The thickest dredged material deposits
outside the disposal site were observed just north of the site boundary, closer to the harbor
entrance. This indicates historic "short-dumping," or disposal from scows before they reach the
disposal zone with the site. The benthic communities within and surrounding the site were not
statistically different in terms of species diversity, abundances, or richness. Successional stage
evaluation of the dredged material deposits, including deposits found outside of the disposal
site, showed fairly uniformly stage I on III benthic communities. These communities are
characterized by organisms present at the sediment surface (stage I) and more mature
organisms present in burrows within the sediment (stage III). Stage I on III communities indicate
rapid recolonization after dredged material disposal and a well-established infaunal community,
suggesting no adverse impacts. Species diversity was high and  abundances tended to be low at
all stations. The infaunal abundance in this 2013 survey was similar to the infaunal abundance
measured by the 1980 baseline. Stations within the disposal site had substantially more gravel
and more fine sediments than those outside the  site that represent native sandy seafloor
conditions. The percentage of fine sediments and gravel within the disposal site increased
compared to the  1980 baseline. This pattern reflects the character of dredged material typically
disposed at this site, which often includes gravel-sized coral rubble, and fine sediments from
land-side runoff that settles in harbors, berths, and navigation channels.

Sediment chemical analysis showed low but variable concentrations of most chemical
constituents. At both inside and outside stations, cadmium,  chromium,  copper, and mercury
were found at concentrations above their NOAA ERL (Table 1).  Sediment chemical
concentrations above the  NOAA ERL, but below the NOAA ERM, are not likely to be harmful to
benthic organisms, but are considered by EPA, in the context of other evidence, when making
environmental management decisions. Chromium, copper, and mercury concentrations were
slightly higher at  stations inside the disposal site than those outside the site. Except for copper
concentrations, dredged material disposal generally had not appreciably increased the
contaminant loads inside the  site compared to 1980 concentrations. Nickel was the only
chemical constituent that exceeded its NOAA  ERM. Nickel concentrations exceeded its NOAA
ERM at all stations inside  the disposal site and at one station outside the site. Much of the
geomorphological character of the sediments in this area is related to the original volcanic
formation of the Hawaiian Islands, which are naturally elevated in nickel concentration.
Therefore, these nickel concentrations are not reason for concern. Organic contaminant
constituents (dioxins, DDTs, organotins, PAHs, and PCBs) were found in low concentrations. In
general, PCB concentrations  were found to be higher at stations inside the site compared to
stations outside of the site. PCBs  and DDTs exceeded their respective ERL at only one station
inside and one station outside the disposal site. These screening level  exceedances were
relatively small in magnitude.  The few constituents found at higher concentrations within the
disposal site are  not considered to represent a risk to the marine environment.

Geophysical measurements used to estimate the total volume of dredged material at South
Oahu ODMDS and correlated well with the recorded volumes of dredged material disposed at
this site, as reported by the USAGE Honolulu District. The SPI and PVP showed dredged
material present within and outside site boundaries. The sub-bottom seismic-reflection profiler
showed that dredged material deposits varied from three to twelve feet in thickness. The
calculated overall dredged material volume within the disposal site was 1,736,000 cubic yards.
This was similar to the 1,855,230  cubic yards permitted by the USAGE Honolulu District from
2002 to 2013.
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2013 National Ocean Dumping Site Monitoring Assessment Report
      Table 1. Summary of Sediment Physical and Chemical Analyses, South Oahu ODMDS
Analyte
Gravel
Sand
Silt
Clay
TOC
Arsenic
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium
Silver
Zinc
Dioxins- Total TEQ
Total DDTs
Total Organotins
Total PAHs
Total PCB Congeners
Units
%
%
%
%
%
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
ppt
ppb
ppt
ppb
ppb
*exceedsNOAAERL
Inside
ODMDS, Avg.
22
44
21
12
1.36
22*
0.53
118*
59*
38
0.19*
88**
ND
ND
89
4.02
ND
2.81
324
19.58
Outside
ODMDS, Avg.
3
77
14
5
0.55
33*
0.42
67
24
21
0.09
41*
ND
ND
54
1.40
ND
3.18
565
7.83
**exceedsNOAAERM
Based on the data collected in the survey, Region 9 confirmed that environmentally acceptable
conditions are being met at the site and, at this time, does not recommend any changes to be
incorporated during the upcoming update of the site's SMMP. Region 9 found that dredged
material had extended past site boundaries, but concluded that this is not due  to recent disposal
activities. Historic and recent dredged material disposal have predictably caused changes to the
sediment grain size within the ODMDS. Other characteristics, like sediment chemistry and
benthic communities, were found to be similar within and outside the disposal site.  Differences
between sediment chemistry and benthic community data collected in 2013 and in  1980 are the
result of localized impacts of disposal activities followed by relatively rapid recovery. Region 9
determined that these ocean disposal activities have not caused significant adverse impacts.
Region 9 concluded that continued use of the site should similarly result in no significant
adverse effects.

      3.11 Region 10-Chetco ODMDS, Oregon

Region 10 monitored the Chetco ODMDS, located off the Oregon coast. The Region conducted
a monitoring survey in conjunction with the Coquille ODMDS survey in September 2013 aboard
Oregon State University's R/V Pacific Storm through an interagency agreement with the
USAGE. In addition, supported by Region 10 funds, the Region conducted a dive survey in
August 2013 aboard a Region 10 vessel. The objective of these surveys was to identify if
disposal at Chetco ODMDS is causing significant adverse impacts and obtain information
needed to update the SMMP.

For the monitoring survey, Region 10 collected sediment samples from eight stations, including
four stations within the disposal site and four stations surrounding the disposal site. Region 10
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analyzed sediment samples for grain size and benthic infaunal community parameters at all
stations, and chemical constituents at stations within the disposal site. Region 10 compared the
chemical analysis results to marine screening levels (SLs) established in the May 2009
Sediment Evaluation Framework (SEF) for the Pacific Northwest (USAGE et a/., 2009).
Concentrations below the SEF SLs are not toxic to benthic organisms. The dive survey
collected video imagery and still photography of the seafloor along five transects throughout the
disposal site.

Analysis of sediment samples from the Chetco ODMDS found no chemical  contaminants at
levels exceeding SEF SLs. The metals arsenic, chromium, copper, lead, zinc, and mercury, as
well as PAHs and other organic compounds, were detected in all samples,  but the
concentrations were well below the SEF SLs. There is no SEF SL for nickel, but Region 10 does
not expect adverse impacts to the benthic community from the observed nickel concentrations.
No tributyltins or pesticides were detected.

The results showed no discernable differences in grain size and benthic infaunal communities
between sampling locations within and  surrounding the site. Grain size of sediments varied from
fine-grains to gravel. Six of the eight stations sampled were predominantly sand (>75%). The
other two stations were either predominantly fine sediments or comprised of both sand and
gravel. This was  consistent with the dive survey results, which recorded various substrate types,
including coarse  sand, gravel/cobble, and rocky reefs. Analysis of benthic infauna found no
discernable difference in community indices (abundance, richness, evenness, density, and
diversity) within and surrounding the disposal site. There were, however, more individuals and
taxa captured at the surrounding stations. The benthic infauna found at stations within and
surrounding the site were  typical for the sand dwelling communities on the Oregon coast.

The dive survey found both low- and high-relief rocky reefs within the disposal site. Some  of the
high-relief rocky reefs identified extended up to 10 feet above the seafloor.  These large high-
relief rocky reefs had well-established sessile invertebrate communities  along with typical
groundfish species.

From these surveys, Region 10 found that disposal  activities are not adversely impacting the
bottom sediments, benthic community,  or reef communities. However, Region 10 believes that
protecting the large high-relief rocky reef communities within the site should be a priority, and
plans to adjust disposal operations accordingly to avoid disposal within these discrete areas.
Region 10 plans  to revise and update the SMMP for this site.

Based on  the data collected in the survey, Region 10 confirmed that environmentally acceptable
conditions are being met at the site, but recommends some changes to dredged material
disposal operations and monitoring at the site to safeguard rocky habitat. Region 10 will
continue to conduct physical, chemical, and infaunal analysis of the sediment and conduct
visual surveys of macroinvertebrates along repeatable transects in order to obtain a  better
understanding of community structure and potential changes within the rocky substrate of the
disposal site. Region 10 also plans to implement a sampling scheme designed to detect
statistically significant differences in species composition within and surrounding of the disposal
site.

       3.12 Region 10 - Coos Bay Sites F and H, Oregon

Region 10 monitored the Coos Bay Sites F and H, located off the southern  Oregon coast.  The
Region conducted this monitoring survey in August  2013 aboard the privately owned vessel R/V
Miss Linda through an interagency agreement with the USAGE and with additional USAGE
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support. The objectives of this survey were to evaluate the impact of disposal at Coos Bay Sites
F and H and to provide sufficient information to update the SMMP.

Region 10 obtained samples from stations within and surrounding Sites F and H. The Region
collected sediment samples from 26 stations, including seven stations within Site F, seven
stations surrounding Site F,  six stations within Site H, and six stations surrounding Site H.
Sediment samples were analyzed for grain size and benthic infaunal community parameters at
all stations, while only samples collected from within the disposal sites were analyzed for
chemical constituents. Region 10 conducted four benthic trawls within and surrounding Site H
and three benthic trawls within Site  F to assess epibenthic invertebrates and demersal fish in
those areas. Additionally, because Site H received an unexpectedly large volume of fine-grained
dredged material in 2009, Region 10 conducted sediment biological assessments (bioassays) at
the stations within Site H. The Region used the bioassay results to determine if benthic
invertebrates were exposed to toxic pollutants. Region 10 compared the chemical analyses
results to marine SLs established in the May 2009 SEF for the Pacific Northwest (USAGE et a/.,
2009). Concentrations below the SEF SLs are not toxic to benthic organisms.

Sediment samples revealed no toxic chemical constituents in sediments collected from Sites F
and H. Eight metals (antimony, arsenic, cadmium, chromium, copper, lead, zinc, and mercury)
were detected in samples from all stations; the concentrations were well below the SEF SLs.
There is no SEF SL for nickel, but the observed nickel concentrations are not expected to have
any impacts on the benthic community. No PCBs or pesticides were detected. The tributyltins
and organic compounds detected were at very low concentrations and well below the SEF SLs.
In addition, all sediments passed the bioassay tests, supporting the chemical analysis that
sediments within Site H did not have adverse effects on the test species. This indicates that the
increased volume of material disposed of at Site H in 2009 did not expose benthic invertebrates
to toxic pollutants.

There were no discernable differences between grain size and benthic infaunal communities
within and surrounding the sites. At  stations within and surrounding Site F, sediments averaged
96% sand. At stations within and surrounding Site H, sediments averaged 81% sand. Sediment
within Site H had a greater percentage of total sand  compared to the finer-grained sediment
found surrounding the site. The benthic community indices, abundance  and  richness, were
lower within Sites F and H than at areas surrounding the sites. However, the benthic community
diversity was higher within the sites  than surrounding the sites.  Despite  this variability between
stations within and surrounding the  disposal  sites, the species density, richness, and diversity
were within the normal range for soft-bottom nearshore habitats in the eastern Pacific.

Based on the data collected in the survey, Region 10 confirmed that environmentally acceptable
conditions are being met at the site  and, at this time, does not recommend any changes to be
incorporated during the upcoming update of the sites' SMMP. Region 10 concludes that
disposal activities are not adversely impacting the bottom sediments or  benthic and epibenthic
community. Benthic trawls indicate that benthic and epibenthic communities within and
surrounding the sites appear to be healthy. Region 10 recommends further analysis to fully
evaluate the impact of disposal activities on sediment characteristics  and  benthic community.
Survey results indicate that the dredged material is moving beyond site  boundaries. For
confirmation, Region  10 plans to conduct additional physical sediment analyses surrounding the
site. The Region  also plans to direct their sampling to detect statistically significant differences
between the benthic communities within and surrounding the disposal sites and the relationship
between grain size and benthic community composition.
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       3.13 Region 10 - Coquille ODMDS, Oregon

Region 10 monitored the Coquille ODMDS, located off the southern Oregon coast. The Region
conducted this monitoring survey in conjunction with the Chetco ODMDS survey in September
2013 aboard Oregon State University's R/V Pacific Storm through an interagency agreement
with USAGE. The objectives of this survey were to provide monitoring data as part of a
continuing effort to evaluate disposal  impacts, provide sufficient information to update the
SMMP, and collect information to evaluate future disposal areas.

The Region collected sediment samples from 18 stations, including nine stations within the
disposal site and nine stations surrounding the disposal site. They analyzed sediment samples
for grain size and benthic infauna at all stations, and chemical constituents at stations within the
disposal site. The Region also conducted four total benthic trawls within and surrounding the
disposal site to assess epibenthic invertebrates (invertebrates that live close or on bottom
sediments) and demersal fish (fish that live near bottom sediments). Region 10 compared the
results from the chemical analyses to marine SLs established in the May 2009 SEF for the
Pacific Northwest (USAGE et a/., 2009). Concentrations below the SEF SLs are not toxic to
benthic organisms.

Sediment samples revealed no toxic chemical constituents in the Coquille ODMDS sediments.
EPA scientists detected the metals arsenic, chromium, copper, zinc, and mercury in  samples
from most stations, but the concentrations were well below the SEF SLs. There  is no SEF SL for
nickel, but Region 10 does not expect any adverse impacts from the observed concentrations.
No tributyltins,  PAHs, PCBs, or pesticides were detected. Only two organic compounds were
present in sediments at measurable concentrations (phenol and benzoic acid), which were
present at two different stations at concentrations slightly above method detection limits.

The results showed no discernable differences between grain size and benthic infaunal
communities at stations within and surrounding the site. Sediments from all stations averaged
96% sand. Analysis of  benthic infauna found no discernable differences within versus
surrounding the disposal site. The benthic infauna was typical for sand-dwelling communities on
the Oregon coast. Region 10 did note the importance of the presence of the annelid  species
Spiophanes bombyx. Region 10 used this species as an indicator of disturbed habitats. This
species is one of the first species to inhabit a newly disturbed area, such as areas with newly
deposited dredged material. The high occurrence of this species at two stations located
northeast of the disposal site suggested that this area is regularly disturbed either by disposal
activities  or natural processes.

It is unclear whether disposal activities have adversely impacted the demersal fish and
epibenthic invertebrates present in the area. Comparisons among the sampled trawl sites
indicated that the disposal site had lower diversities and abundances of demersal fish and
epibenthic invertebrates. However, Region 10 was unable to determine if disposal activities
directly caused the lower diversities and abundances. The low number of trawls executed does
not allow Region 10 to  perform statistical analyses on the data. Additionally, one trawl
conducted within the disposal site was shorter than the other three, which would likely lead to
fewer organisms  being collected.

Based on the data collected in the survey, Region  10 confirmed that environmentally acceptable
conditions are being met at the site and, at this time, does not recommend any changes to be
incorporated during the upcoming update of the site's SMMP. Region  10 concludes that
disposal activities are not negatively impacting the bottom sediments or benthic and  epibenthic
community. Region 10 plans to continue conducting monitoring to fully evaluate the impact of
disposal activities on the benthic and  epibenthic communities. A benthic video sled may be used


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instead of a benthic trawl for future surveys because video eliminates the need to capture and
release organisms and creates a permanent visual record of the seafloor. The Region may also
use dive surveys to better evaluate bottom substrates. These dive surveys could focus on areas
to the northeast of the disposal site to determine if disposal activities are regularly disturbing the
area, as suggested by the high occurrence of Spiophanes bombyx.

      3.14 Region 10 - Mouth of the Columbia River Deep Water Site, Oregon

Region 10 monitored the Mouth of the Columbia River (MCR) Deep Water Site (DWS), located
off the coast of Oregon and Washington. The Region conducted this monitoring survey in
August 2013 aboard two privately owned vessels, R/V NRC Quest and David Evans and
Associate's S/V Preston, both obtained through an interagency agreement with the USAGE.
The objectives of this survey were to determine if dredged material has moved outside of the
designated disposal zone, DWS-07, and qualitatively assess the stage of the benthic
community. This monitoring survey focused on disposal zone DWS-07, one of four disposal
zones established for the disposal of dredged material within the MCR DWS.

Aboard the NRC Quest, Region 10 collected sediment samples from within and outside of the
DWS-07 disposal zone. The samples were obtained from six stations within the disposal site,
including four stations within the designated disposal zone and two stations surrounding the
designated disposal zone. SPI were obtained from 36 stations within disposal site, including 26
stations within the designated disposal zone and 10 stations surrounding the designated
disposal zone). Sediment samples were analyzed for sediment grain size and SPI were
analyzed for sediment grain size and benthic infaunal community parameters. Aboard the S/V
Preston, Region 10 collected multibeam bathymetry data and side scan sonar data to determine
the extent of the disposal footprint.

Analyses of SPI and multibeam  bathymetry suggested that dredged material extended past the
designated disposal zone, DWS-07. Grain size within and outside disposal zone DWS-07 was
predominantly sand (89-97%). However, stations outside the disposal  zone contained slightly
more finer-grained material (10%) than stations within the disposal zone (3-4%). SPI  results
showed that dredged material found within the disposal zone consisted of both  recent and older
disposals while the dredged material found outside the disposal zone consisted of older
disposals. Using the remote sensing data, USAGE conducted a site capacity assessment in
which they found that approximately 25% of the dredged material disposed within DWS-07 has
moved northward after placement.

Derelict fishing gear is prevalent within the disposal zone. An unintended observation from the
side-scan sonar data found 60 derelict crab pots on the seafloor. The disposal site is within
commercial fishing grounds for the Dungeness crab. Therefore, the  marine debris may be
ghost-fishing because of the lost fishing gear. Region 10 would like to  assess the prevalence of
derelict crab pots within the disposal site. This information would inform the potential for creating
a partnership with other federal agencies and the local fishing community to remove the debris.

Results from the SPI survey indicated that the benthic communities within and outside the
disposal zone were in different stages of recovery from disposal. The USAGE had disposed of
dredged material from 2007 to 2013 (EPA's survey occurred prior to the disposal in 2013). The
benthic community within the disposal zone was primarily stage I infauna, or the first organisms
to colonize the sediment surface following a disturbance. This  indicated that the benthic
community within the disposal zone was disturbed and, at the time of the survey, was still in
initial recovery 9 months after disposal.  Outside of the disposal zone, however, the benthic
community was in a  more mature successional stage, stage I on III.  These communities are
characterized by organisms present at the sediment surface (stage I) and more mature


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organisms present in burrows within the sediment (stage III). Although stage I on III
communities are more mature benthic communities than stage I, it is inconclusive as to whether
the stage I on III is a fully-recovered community. Interpretation of the benthic infaunal
successional stages from SPI is not well understood in sandy sediments.

In this survey, Region 10 found that the SPI camera had difficulty penetrating the sandy bottom
substrates of the disposal zone. Average penetration depth of the camera was four centimeters.
This shallow penetration depth was not sufficient to determine depths of dredged material
because the camera could not go deep enough to image native substrate. Furthermore, the
dredged material is visually similar, albeit quantitatively and potentially ecologically  different,
from native sediments. Thus, even when it was believed the camera to have penetrated deep
enough to reach native sediments, there was difficulty discerning the differentiation  point
between the two layers. For future studies, Region 10 will reconsider the use of SPI in disposal
site surveys where the substrate is predominantly sandy.

Based  on the data collected in the survey and additional work by USAGE Portland District,
Region 10 plans to change the sampling area for future surveys. Region 10 concluded that,
contrary to what was understood at the time of site designation, dredged material is moving
northward and southward by active bottom transport processes after disposal. To better
understand this movement, future grain size sampling should have stations placed further away
from the disposal zone and out of the northerly dispersal path. The multibeam survey area will
also be expanded beyond disposal zone boundaries.

4.0 Conclusion

In FY 2013, EPA Scientists used various scientifically sound methods to obtain data at 20 ocean
disposal sites monitored during 13 separate surveys. The most common survey methods were
sediment grabs and video and still underwater imagery (SPI, PVP, multibeam bathymetry). EPA
collected sediment grabs at 14 of the 20 disposal sites surveyed and video and still underwater
imagery from seven of the 20 disposal sites surveyed. In all, scientists collected sediment grabs
from a  total of 200 stations and SPI from a total of 302 stations. In addition, EPA Regions
conducted dive operations, fish trawls, bioassays, and water sampling.

EPA confirmed that environmentally acceptable conditions were met at 14 of 20 ocean disposal
sites surveyed in FY 2013. At these 14 sites, EPA determined that dredged material disposal
had not adversely impacted the ecosystem, permitted disposal could continue, and  no further
action was needed. At three of the six other ocean disposal sites surveyed (Sabine-Neches
Sites 3 and 4 and Mouth of the Columbia River Deep Water Site), further investigation of the
site conditions is necessary to determine if any changes in management practices are needed.
And at the last three ocean disposal sites (Charleston, Jacksonville, and Chetco), EPA
determined that modifications to the boundaries and/or permitted use of the site are necessary
to sustain environmentally acceptable conditions for future management of the sites. Findings at
these six sites are discussed in the following paragraphs.

Surveys at Sabine-Neches  Sites 3 and 4 and Mouth of the Columbia River Deep Water Site
showed that additional investigation is necessary. Monitoring at Sabine-Neches Sites 3 and 4
(TX) revealed hotspots of high metal concentrations in sediments. High metal concentrations in
sediments can cause adverse effects to organisms that live on, in, or near the seafloor. These
metals can also magnify as they are transferred up the food chain, ultimately impacting higher
trophic level species, such as large marine predators and humans. EPA plans to conduct
additional surveys at these  sites focused on the hotspots to identify if any management actions
are needed to prevent the occurrence of adverse effects. From the survey at the Mouth of the
Columbia River (OR), EPA  found that the migration of dredged material after disposal was

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different than anticipated. EPA plans to conduct additional studies at the site to explore the fate
and transport of material after disposal and ensure that it will not impact marine life or navigation
in this area.

Finally, surveys at Charleston,  Jacksonville, and Chetco led EPA to determine that, in order to
sustain environmentally acceptable conditions for future management of the sites, modifications
to site boundaries and/or permitted use were necessary.  EPA conducted a wave and current
study at Charleston (SC)  to better understand the fate and transport (and potential impacts) of a
significant increase in dredged material disposal planned for the site. This material will come
from a project to deepen Charleston Harbor to accommodate post-Panamax ships. Based on
the data and information evaluated to date, EPA currently anticipates that the material  is likely to
move outside of site boundaries and that the disposal zone within the site should be enlarged to
prevent adverse environmental impacts offsite. At Jacksonville (FL), EPA analyzed SPI, which
demonstrates that dredged material had migrated off the site to the north and south. As a result,
EPA plans to restrict the release zone at the disposal site farther from site boundaries to prevent
impact to the benthic communities outside of site boundaries. Lastly, EPA (with USAGE)
conducted a survey at Chetco (OR) to evaluate whether dredged material disposal was
impacting nearby rocky reef habitat. EPA determined that, while disposal activities had not yet
adversely impacted reef communities, adjustments to site usage are warranted to safeguard this
valuable habitat resource.

Under the MPRSA, EPA is responsible for designating and managing ocean disposal sites for
permitted disposal of dredged material. EPA monitors the environment within and around each
site to verify that disposal does not cause unanticipated or significant adverse effects and that
terms of MPRSA permits are met. The findings and conclusions that EPA reached based on the
monitoring data collected in FY 2013 demonstrates that current conditions at the vast majority of
ocean disposal sites show no evidence of adverse effects. At a few sites, EPA observed,
suspected, or anticipated adverse effects. In these cases, EPA has taken site management
actions to address the issues in the present and prevent adverse effects in the future.

5.0 Acknowledgements

This report is based on the monitoring surveys conducted, analyses performed, and conclusions
drawn by EPA Regional Offices 2, 3, 4, 6, 9, and 10 during FY2013. This report was developed
with the support of Ocean Dumping staff from EPA Headquarters and all coastal  Regional
offices.

6.0 References

EPA and USAGE. 2007. Jacksonville  Ocean Dredged Material Disposal Site,  Site Management
      and Monitoring Plan.  November 2007. Prepared by U.S. Environmental Protection
      Agency, Region 4, and  U.S. Army Corps of Engineers, Jacksonville District.
      http://www.epa.gov/region4/water/oceans/documents/Jacksonville ODMDS  SMMP  200
      7.pdf

Long, ER and Macdonald, DD. "Recommended Use of Empirically Derived Sediment Quality
      Guidelines for Marine and Estuarine Ecosystems," Human and Ecological Risk
      Assessment, Vol.  4, No. 5, 1998,  pp. 1019- 1039. doi:10.1080/10807039891284956.

National Oceans Economics Program. 2016. State of the U.S. Ocean and Coastal Economies.
      2016 Update. Middlebury Institute of International Studies at Monterrey.
      http://www.oceaneconomics.org/
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2013 National Ocean Dumping Site Monitoring Assessment Report
NOAA. 1999. Sediment Quality Guidelines Developed for the National Status and Trends
       Program, http://archive.orr.noaa.gov/book shelf/121  sedi  qual guide.pdf

Pielou, EC. 1966. The measurement of diversity in different types of biological collections.
       Journal of Theoretical Biology 13:131-144.

USAGE et a/. 2009. Sediment Evaluation Framework for the Pacific Northwest. May 2009.
       http://www.nwp.usace.armv.mil/Portals/24/docs/environment/sediment/2009 SEF Pacifi
       c  NW.pdf

7.0 Appendix - Site Characteristics of Disposal Sites Surveys in FY2013
Region
2
2
2
3
4
4
4
4
4
6
6
6
6
9
9
10
10
10
10
10
Disposal Site
Arecibo
Mayaguez
San Juan
Dam Neck
Charleston Harbor
Fernandina Beach
Jacksonville
Pensacola Offshore
Tampa Bay
Sabine-Neches Site 1
Sabine-Neches Site 2
Sabine-Neches Site 3
Sabine Neches Site 4
Hilo
South Oahu
Chetco
Coos Bay Site F
Coos Bay Site H
Coquille
Mouth of Columbia River DWS
Size (nm2)
1.00
1.00
0.98
8.00
7.50
4.00
1.00
4.53
4.00
2.40
4.20
4.70
4.20
0.78
1.52
0.09
3.18
0.13
0.17
10.59
Depth (ft)
333.36- 1368.11
1151.57- 1259.84
656.17- 1312.34
Average 40.0
Average 36.09
37.0- 69.0
32.0- 60.0
65.0- 80.0
70.0- 90.0
36.09- 42.65
29.53- 42.65
39.37- 42.65
16.40-29.53
1082.68- 1115.49
1312.34- 1558.40
60.0- 85.0
20.0- 160.0
160.0-210.0
40.0- 85.0
200.0- 300.0
EPA Ocean Dumping Program
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