&EPA
Unned States
Environmental Protection
Agency
Environmental Research
Laboratory
Corvallis, OR 97330
EPA 600 3-78-084
September 1978
Research and Development
Management of Bottom
Sediments Containing
Toxic Substances
Proceedings of the Third U.S.-
Japan Experts' Meeting
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are
1 Environmental Health Effects Research
2. Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
cies, and materials. Problems are assessed for their long- and short-term influ-
ences. Investigations include formation, transport, and pathway studies to deter-
mine the fate of pollutants and their effects. This work provides the technical basis
for setting standards to minimize undesirable changes in living organisms in the
aquatic, terrestrial, and atmospheric environments.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/3-78-084
September 1978
MANAGEMENT OF BOTTOM SEDIMENTS CONTAINING TOXIC SUBSTANCES
Proceedings of the Third U.S.-Japan Experts' Meeting
November 1977 -- Easton, Maryland
edited by
Spencer A. Peterson and Karen K. Randolph
Corvallis Environmental Research Laboratory
Corvallis, Oregon 97330
CORVALLIS ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CORVALLIS, OREGON 97330
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DISCLAIMER
This report has been reviewed by the Corvallis Environmental
Research Laboratory, U.S. Environmental Protection Agency,
and approved for publication. Approval does not signify that
the contents necessarily reflect the views and policies of
the U.S. Environmental Protection Agency, nor does mention of
trade names or commercial products constitute endorsement for
use. The individual authors assume responsibility for the
technical accuracy of the papers included in this
Proceedings.
-------
FOREWORD
Effective regulatory and enforcement actions by the
Environmental Protection Agency would be virtually impossible
without sound scientific data on pollutants and their impact
on environmental stability and human health. Responsibility
for building this data base has been assigned to EPA's Office
of Research and Development and its 15 major field
installations, one of which is the Corvallis Environmental
Research Laboratory (CERL).
The primary mission of the Corvallis Laboratory is research
on the effects of environmental pollutants on terrestrial,
freshwater, and marine ecosystems; the behavior, effects and
control of pollutants in lake systems; and the development of
predictive models on the movements of pollutants in the
biosphere. The United States-Japan Ministerial Agreement of
May 1974 provided for the exchange of environmental
information in several areas of mutual concern. This report
is the compilation of papers presented at the Third U.S.-
Japan Experts' Meeting on the Management of Bottom Sediments
Containing Toxic Substances which was held November 15-17,
1977 in Easton, Maryland. The first meeting was held in Cor-
vallis, Oregon, in November 1975. The second session was
hosted by the Japanese Government in October 1976. The 1979
meeting will be held in Japan.
A. F. Bartsch, CERL Director
and U.S. Coordinator for the
U.S.-Japan Experts' Meeting
-------
CONTENTS
JAPANESE PAPERS
Control of Toxic Effluents and Management of Toxic Bottom
Sediments 1
T. Hayashi
Present and Future Water Pollution Control Projects in
Japanese Rivers and Lakes 11
A. Kato
Turbidity Generated by Dredging Projects 31
0. Nakai
Recent Progress in Techniques for Managing Contaminated
Bottom Sediments 49
H. Koba
Dredging Toxic Sediments in Yokkaichi Port 65
H. Ito
Accumulation of Methyl Mercury in Red Sea Bream (Crysophrys
major) via the Food Chain 87
M. Fujiki
The Relationship Between Sediments and Benthos in Mikawa Bay. . 95
T. Otsuki
A Hydrodynamic Study of Lake Pollution 121
T. Yoshida
UNITED STATES PAPERS
The Toxic Substances Control Act (TSCA): How it Affects EPA
from a Research and Enforcement Standpoint 147
E. Wall en
Mitigation Feasibility for the Kepone-Contaminated James River,
Virginia 153
K. Mackenthun, M. Brossman, J. Kohler, C. Terrell
Hudson River-PCB Study Description and Detailed Work Plan . . . 183
E. Horn and L. Hetling
An Overview of Bottom Sediment Problems in Saginaw River and
Bay, Marinette-Menominee Harbor, and Waukegan Harbor 199
K. Bremer
Impacts Associated With the Discharge of Dredged Material
into Open Water 213
R. Engler
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A Bioassay for the Toxicity of Sediment to the Marine
Macrobenthos 225
R. Swartz, W. DeBen, F. Cole
Eutrophication Control: Importance of Internal Phosphorus
Supplies 239
D. Larsen and D. Schults
The Regulation Guidelines and Criteria for the Discharge of
Dredged Material: Prediction of Pollution Potential 263
R. Engler
Densification, Treatment, and Management of Dredged Material
Disposal Areas 273
C. Calhoun Jr.
APPENDIX 291
VI
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CONTROL OF TOXIC EFFLUENTS AND
MANAGEMENT OF TOXIC BOTTOM SEDIMENTS
Toru Hayashi
Chief, Water Quality Management Division,
Water Quality Bureau, Environment Agency
INTRODUCTION
In recent years, the decline in Japanese water quality has ceased and
there has been a trend toward slow recovery. Water pollution caused by
cadmium and other toxic substances has stabilized and pollution from organic
substances has, since 1969, definitely slowed -- even improved in certain
areas. This is due to the rigorous control of effluents throughout the
country in recent years. However, there are still areas where water pollution
is severe, especially in rivers that run through cities with high populations
and heavy industrial concentrations and in bays and inland seas where exchange
rates with the sea are slow.
This paper explains the water pollution control measures designed to
regulate the discharge of toxic substances and treat bottom sediments contain-
ing toxic substances.
MERCURY
The organic mercury poisoning which afflicted the inhabitants of Minamata
and Niigata focused considerable public attention on the problem of mercury
poisoning. This attention was heightened in 1973 by the suspected mercury
contamination in Ariako Bay, which caused the government to call a conference
on June 12, 1973, to establish countermeasures against mercury pollution.
The conference, under the chairmanship of the Director-General of the Environ-
mental Agency, adopted a series of measures to control mercury pollution,
including a nationwide environmental survey, improved standards and vigorous
administrative guidance for those industries involved as sources of the
contaminants.
SURVEY OF MERCURY POLLUTION
The nationwide comprehensive environmental survey was conducted in areas
where mercury contamination of fish products was reported (prior to 1973) and
in areas adjacent to mercury-handling factories and mercury mines. Fish
products, water quality, bottom sediments, soil and agricultural products
were examined.
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The 22,403 samples of fish products examined during the investigation
included 303 species collected from 268 aquatic sites (124 inland and 144
marine). The results showed that the contents of mercury pollutants in
almost all of the samples of marine fish were below the provisional acceptable
levels of 0.4 ppm of total mercury and 0.3 ppm of methyl mercury, and that
most of the samples of river fish were also below acceptable levels. The
government concluded that there was no cause to restrict fishing or sale of
fish in most areas. However, in certain parts of Minamala Bay, Tokuyama Bay,
the area off Naoetsu, and Kagoshima Bay, the mercury contents of certain
species of fish exceeded the provisional acceptable level. Fishermen in
these areas voluntarily refrained from fishing. The pollution of water and
bottom deposits in Minamata Bay and Tokuyama Bay, and of water off Naoetsu is
attributed to accumulated mercury-containing effluents discharged in the past
from nearby factories. Although mercury content of fish in Kagoshima Bay
exceeded the provisional level of 0.4 ppm total mercury, the mercury concen-
tration in the water and bottom deposits was no different from those of other
unpolluted marine areas. The polluted fish are attributed to the effects of
volcanic activity on the floor of the bay.
Fishing in these polluted areas is still restricted today. Particular
fish species caught in certain parts of nine rivers adjacent to mercury mines
were found to contain mercury in excess of the corresponding provisional
acceptable level. The inhabitants of the river basins have been warned
against eating them. In inland and marine areas, where the problem of mercury
pollution still remains unsolved, surveys of fish catches and fish products
are being conducted regularly.
The survey of water quality involved a total of 3,768 samples taken from
634 sites consisting of 331 rivers, 156 harbors and 147 marine areas. Of
these, 76 samples (2.0% of the total) were found to contain total mercury in
excess of the environmental quality standards. These samples were traced to
four rivers and two marine areas. The Environmental Agency will identify the
cause of this pollution and take suitable measures to counteract it.
The survey of the quality of bottom deposits was made on a total of
5,656 samples taken from 647 sites consisting of 341 rivers, 158 harbors and
148 marine areas. The results showed bottom deposits from 27 sites (16
rivers and 11 bays) which contained mercury in excess of the provisional
acceptable level.
To prevent additional mercury pollution it is essential to effectively
treat mercury-containing effluents and to control disposal of mercury-
containing wastes. The Water Pollution Control Law of 1971 extended regula-
tion of effluents from a small number of regions to the entire nation.
Effluent standards were established and those relating to mercury were made
more stringent in 1974. The revised effluent standards have been an important
factor in the dramatic improvement of the quality of effluents. By June,
1974, factories manufacturing acetylene-based vinyl polymer chloride and
acetylene-based acetaldehyde (the two major sources of mercury-containing
effluents) either discontinued their production, changed their processes or
terminated effluent discharge outside the plant. The closing-off of effluents
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from factories manufacturing caustic soda using the mercury process was
completed at almost all factories by December, 1973. In addition, plans were
made for a switchover from the mercury process to either the asbestos dia-
phragm or ion-exchange diaphragm process of manufacturing caustic soda. The
schedule had aimed at two-thirds conversion by September, 1975, and completion
by March, 1978. The interim goal of two-thirds conversion was reached by the
end of FY 1975. However, the attainment of full switchover will be difficult
under present circumstances because:
(1) Caustic soda produced by the asbestos diaphragm process is not as
readily accepted by consumers because of its lower quality.
(2) Commercial development of the ion-exchange diaphragm process is not
yet complete.
(3) A large amount of capital is required to convert to the ion-
exchange diaphragm process, and the caustic soda business has
declined recently so capital is not readily available.
Therefore, accelerated development of the ion-exchange diaphragm process
is urgently needed. It is important to continue to monitor effluents dis-
charged from mercury-process factories until conversion has been accomplished.
REMOVAL OF MERCURY-CONTAMINATED SEDIMENT
To help prevent pollution of fish products from mercury-contaminated
bottom deposits, provisional standards were established for the removal of
polluted sediments on August 31, 1973. These standards were based on the
permissible limits of mercury concentration in fish products (0.4 ppm of
total mercury and 0.3 ppm of methyl mercury), food intake, biological accumu-
lation of mercury (an overall accumulation coefficient of 1,000), release of
mercury from bottom deposits, and its diffusion, mixing and other such factors
in a given area.
As of January, 1976, bottom deposits in 39 water areas were found to be
contaminated by mercury in excess of the provisional removal standards. Of
these, 27 were found by the surveys conducted in fiscal year 1973 and an
additional 12 areas were found in subsequent investigations. Sediment removal
was completed in 29 areas, similar work is under way in 7 others and plans
are being drawn up or detailed investigations under way in the remaining 3
areas.
PCB
A nationwide investigation of aquatic sites for PCB pollution was con-
ducted in 1972 and 1973 concurrent with the mercury pollution survey.
Examination of 3,369 samples of seafood products for PCB contamination
was made in the 20 areas which were found in previous surveys to be contami-
nated. Based on the findings of these examinations, voluntary regulation of
fishing was put into effect in 16 of the areas, and catches are examined
regularly.
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A total of 1,281 water samples taken from 282 aquatic sites were ex-
amined. The samples covered 208 rivers, 28 harbors and 46 marine sites where
fish products were found to be contaminated by PCB, and the bottom deposits
contained more than 1 ppm PCB. Of the total, 55 samples (or 4.3%) were found
to contain PCB in excess of the water quality standards and they were traced
to 18 river areas and 4 marine areas. Efforts are being made to identify the
cause of this pollution in order to establish appropriate measures to prevent
further pollution. When compared with the previous year there are definite
signs of improvement both in the frequency of detection and in the concentra-
tion of PCB.
The survey of bottom deposits examined a total of 1,789 samples taken
from 354 sites covering 258 rivers, 38 bays and 58 marine sites. It was
found that 51 areas containing 42 rivers, 5 bays and 4 marine areas had
bottom deposits containing PCB in excess of the provisional removal standard
of 10 ppm per unit dry weight. The examination also showed that bottom
sediments at 6 sites contained more than TOO ppm, 8 sites contained from 50
to 100 ppm, 11 sites had from 25 to 50 ppm, and 26 sites had from 10 to 25
ppm of PCB.
CONTROL OF PCB SOURCES
The manufacture, use and importing of PCB has been totally banned since
1971 by administrative policy. It is now banned by law except for specifical-
ly authorized purposes. Even in such cases, the manufacturers are under
instructions to maintain control on such products. Necessary measures are
also being enforced to ensure the recall and proper storage of products
containing PCB.
Many items such as discarded appliances, transformers attached to heavy-
duty electrical machinery, condensers and pressure-printing duplicating
papers contain PCB wastes. Measures have been established with the management
of corporations and municipalities for the recall and storage of such wastes.
Adequate disposal of such wastes is being carried out under the amendment of
the Cabinet Order for Implementation of Waste Disposal and the Public Cleans-
ing Law, made in December, 1975, and the enforcement of March, 1976 standards
for disposal of wastes containing PCB.
REMOVAL OF PCB-CONTAMINATED SEDIMENTS
As with mercury pollution, provisional standards for the removal of PCB-
contaminated sediments were also established. To start with, the findings of
the 1972 investigations were used as a basis to set provisional removal
standards at 100 ppm per unit weight of dry sediments. The nation-wide
environmental surveys conducted in fiscal year 1973 provided new data on the
basis of a statistical analysis of PCB concentration in sediments and on the
permissible limits of PCB concentration in fish products, the removal stand-
ards were changed on February 28, 1975, to 10 ppm per unit weight of dry
sediments.
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Sediments in 86 areas were found to contain PCBs exceeding the provision-
al removal standards; 51 of them were found in the investigations conducted in
fiscal year 1973 and 35 of them in other surveys. Projects for the removal of
the contaminated sediments were completed in 25 of these areas and are under
way in 20 others. Similar projects are planned for 9 areas and, as of December,
1975, further investigations are being conducted in the remaining 32 pol-
luted sites. Most of the contaminated sediments are either buried on the
premises of factories, contained in concrete pits, or are buried elsewhere.
RESULTS OF THE MEASURES TO CONTROL PCB CONTAMINATION
Measures employed for the control of environmental contamination by PCB
include the establishment of environmental quality and effluent standards,
removal of contaminated sediments, and improvements made in effluent treatment
facilities. At present, the situation has greatly improved except in some
areas where waste paper recycling factories are located. Pressure-printing
duplicating papers containing PCB must be stored and some of them become
unavoidably mixed with other waste papers.
SEDIMENTS CONTAMINATED BY OTHER HAZARDOUS SUBSTANCES
Besides mercury and PCB, sediments contain other hazardous substances.
The important ones are heavy metals like cadmium, chromium, copper and zinc,
and also petroleum. There are no investigations now under way for the study
of those materials in water, bottom sediments or biota.
WATER QUALITY
The emphasis of measures designed to control discharge of harmful sub-
stances into the public waters of Japan has been directed toward the estab-
lishment of environmental quality standards and effluent standards as well as
the improvement of water quality surveillance systems and waste water treat-
ment. Table 1 demonstrates that these efforts have begun to bear fruit in
the form of a dramatic decrease in the concentration of harmful substances in
public waters.
The number of samples failing to meet the environmental water quality
standards for cadmium and other toxic substances injurious to human health
has decreased sharply year by year. Of the total samples in FY 1970 and
1975, respectively, the number exceeding the standard fell from 1.4 percent
to 0.17 percent. Moreover, even though the standard for total mercury became
stricter on September 30, 1974, there was no sample site at which the total
mercury detected by water analysis exceeded that allowed by the new standard.
As in previous years neither alkyl mercury nor organic phosphorus was detected
in any of the FY 1975 samples.
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TABLE 1. RATIO OF SAMPLES EXCEEDING ENVIRONMENTAL QUALITY
STANDARDS FOR HARMFUL SUBSTANCES TO TOTAL SAMPLES
Substances
measured
Cadmi urn
Cyanides
Organic
phosphorus
Lead
Chromium
(hexavalent)
-
Fiscal
year
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
No. of samples
examined (A)
2,564
15,944
27,951
30,567
31,915
32,851
2,187
12,453
22,223
23.969
25,060
26,037
1,865
5,116
12,004
11,403
12,304
10,713
2,222
14,515
27,067
30,228
31,818
31,939
552
11,532
22,437
23,856
25,438
25,722
No. of samples
exceeding the
standards (B)
71
114
95
98
119
103
33
142
113
49
16
4
3
11
0
0
0
0
61
202
181
166
118
101
12
15
15
20
8
4
Ratio (%)
(B)/(A)
2.8
0.7
0.34
0.32
0.37
0.31
1.5
1.2
0.5
0.2
0.06
0.02
0.2
0.2
0
0
0
0
2.7
1.4
0.7
0.55
0.37
0.32
0.8
0.1
0.07
0.08
0.03
0.02
continued
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TABLE 1 (continued)
Substances
measured
Arsenics
Total
mercury
Alkyl
mercury
PCB
Total
Fiscal
year
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
1970
1971
1972
1973
1974
1975
1975
1970
1971
1972
1973
1974
1975
No. of samples
examined (A)
1,942
11,530
21,991
23,848
26,005
28,447
2,228
12,360
22,727
24,611
(25,901)
(29,879)
1,603
5,624
10,968
12,590
12,246
11,695
3,063
16,164
89,074
167,368
181,072
164,786
179,534
No. of samples
exceeding the
standards (B)
20
48
64
75
71
67
22
32
8
3
(50)
(74)
0
0
0
0
0
0
10
222
504
476
411
332
291
Ratio (%)
(B)/(A)
1.0
0.4
0.29
0.31
0.27
0.24
1.0
0.3
0.01
0.01
(0.19)
(0.25)
0
0
0
0
0
0
0.33
1.4
0.6
0.3
0.23
0.20
0.17
Source: The Environmental Agency
Remarks: On September 30, 1974, the method for the measurement of total
mercury was changed, with the result that the detectable limit was
lowered. However, under the new limit, no instance was reported in
which the total mercury contents exceeded the environmental quality
standards.
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SEDIMENT CONTAMINATION SURVEY
A sediment contamination survey has been under way since 1973 to investi-
gate the level of hazardous substances in sediments all over the country.
Surveys were conducted as follows:
1973: Detailed investigations in major aquatic areas near mercury mines
and factories manufacturing caustic soda by means of mercury-process
electrolysis. PCB-handling factories were investigated in detail, and
thorough investigations were conducted at other PCB-contaminated sites
and at areas which were not contaminated.
1974: Investigations on mercury pollution in areas where the bottom
deposits contained more that 5 ppm of mercury as determined by the
investigation of the previous year Investigations also were conducted
for 3 major bays (Tokyo Bay, Ise Bay and Seto Inland Sea) and for 10
major lakes (Lake Biwa, etc.). Environmental surveys were conducted in
areas where the removal of PCB contaminated deposits had been completed.
1975 - 76: Investigations in areas where the mercury or PCB concentration
of bottom deposits exceeded 1 ppm as determined by previous investiga-
tions. Investigations were also made in areas where voluntary fishing
restrictions exist and where warnings on eating contaminated fish are in
effect. (See Tables 2, 3 and 4 for statistical details.)
TABLE 2. NUMBER OF AQUATIC AREAS INVESTIGATED
Year
1973
1974
1975
1976
Mercury
Rivers
341
47
132
122
Sea
areas
306
30
71
95
Sub-
total
647
77
203
217
PCB
Rivers
258
37
99
119
Sea
areas
96
6
32
33
Sub-
total
354
43
131
152
Total
Rivers
599
84
231
241
Sea
areas
402
36
103
128
Sub-
total
1,001
120
334
369
8
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TABLE 3. REMOVAL OF CONTAMINATED SEDIMENT (Hg)
As of January, 1977
Completed
In progress
Planning stage
Total
Number of areas
Sea
9
3
3
15
River
20
4
0
24
Total
29
7
3
39
TABLE 4. REMOVAL OF CONTAMINATED SEDIMENT (PCB)
As of August, 1976
Completed
In progress
Planning stage
Total
Number of water areas
Sea
7
3
4
14
River
35
9
15
59
Total
42
12
19
73
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PRESENT AND FUTURE WATER POLLUTION CONTROL
PROJECTS IN JAPANESE RIVERS AND LAKES
Akira Kato
Assistant Manager, River Improvement Division
River Bureau, Ministry of Construction
INTRODUCTION
Water pollution of public rivers and lakes in Japan has a magnified impact
because of the limited water resources of the country. To prevent further
deterioration of water quality, many water pollution control projects are being
conducted under direct control or as grant-in-aid projects of the Ministry of
Construction.
Originally rivers and lakes, especially those near large cities, were being
polluted by domestic and industrial wastewater discharges which resulted in fish
kills and noxious odors. More recently, water pollution has also affected
smaller cities as well, and toxic materials such as mercury and PCB are
accumulating in the beds of rivers and lakes.
To control water pollution at the source the government must set limita-
tions on the discharge of industrial wastewater, encourage improvement of sewage
processing facilities and eliminate direct discharge of pollutants into rivers
(Figure 1). For rivers which are already polluted, the dredging of accumulated
sludge and sediment in river beds or the introduction of clean water are methods
which help to alleviate the problems.
HISTORY OF RIVER POLLUTION CONTROL PROJECTS
The Ministry of Construction started direct control of river water pollu-
tion control projects in 1959 with the Iwabuchi Gate project. This was to
introduce clean water from the Arakawa River into the polluted Sumida River.
The project was completed in 1962. After that came a project associated with
the Tokyo Olympic Games in 1964 where water from the Tone Reservoir was to be
discharged into the Ara River through the Musashi Channel. Water collected
behind the Akigase Dam in the Ara River was to be introduced through the Asaka
Channel into the polluted Shinkashi River located in the upper channel of the
Sumida River. In 1967 the Neya River cleanup project, in which water from the
Yodo River was introduced into the polluted Neya River, was completed as a
project related to the International Exposition in 1970.
River water pollution control projects started as grants-in-aid from the
Ministry of Construction in 1958. The first was a dredging project on the
Sumida River. Many dredging projects near large cities such as Tokyo, Osaka,
and Nagoya, were completed, but still failed to halt the deterioration of water
11
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RIVER POLLUTION
CONTROL MEASURES"
CONTROL BEFORE -
ENTERING RIVERS
CONTROL AFTER
"ENTERING RIVERS
ro
LIMITATIONS ON DISCHARGE
r-OF INDUSTRIAL WASTE
WATER
CONSTRUCTION AND IM-
PROVEMENT OF SEWAGE AND
PROCESSING FACILITIES
DREDGING OF SLUDGE AND
r-SEDIMENTS FROM POLLUTED
BEDS
^-IMPROVEMENT OF WATERWAYS'
CHANNEL FOR MAINTAINING
"WATER QUALITY
—REDUCTION OF POLLUTANTS-
ADDITION OF CLEAN WATER
"FROM OTHER RIVERS
CLEAN WATER SUPPLY FROM
"RESERVOIRS
r-CIRCULATION OF WATER
ADDITION OF CLEAN WATER:
—SEAWATER OR TREATED
EFFLUENTS (Dilution)
SEPARATION OF CLEAN WATER
"AND POLLUTED WATER
PREVENTION OF CONTACT
M)F RIVER WATER WITH
POLLUTANTS
r-OXIDATION POND
SEDIMENTATION TANK
LIME ADDITION FOR
"NEUTRALIZATION
Figure 1. Pollution control measures
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quality near population centers. To cope with this problem the "Urban River
Conservation Section" was created within the River Bureau of the Ministry of
Construction. The budget item known as the "Urban River Environmental
Improvement Project" included dredging of sludge and sediment, construction of
water channels and improvement of river levees and beaches for the recreation of
local citizens.
But environmental problems in rivers did not remain limited only to large
cities. As a result, in 1974 the term "Urban" was deleted from the budget item,
and money became available for improvement of every river with pollution
problems. Tables 1, 2, and 3 list some of the improvement projects.
Dredging for control of river pollution is performed by the Administration
of each river or by the person who discharges the effluent.
The definition of the term "person" is similar to that defined by the
"Federal Water Pollution Control Act " in the United States, i.e., the term
"person" means an individual, corporation, partnership, association, prefec-
ture, municipality, commission, or political subdivision of a prefecture, or any
interprefecture body.
There are two ways in which a private corporation contributes to the
dredging of discharged sediments. One way is when the discharged sediments are
dredged along with those others discharged from numerous unspecified sources
(generally including small- to medium-sized private organizations); the other
is when the corporation bears the entire cost of dredging. The first method is
based on a law which determines the share between public and private
organizations. In this case the river control agencies or Administrator will
perform the dredging. In the second method, the private organization will
perform the project under the guidance of the river control agencies or
Administrator. This is based upon the so-called "Law Concerning Entrepreneurs
Bearing of the Cost of Public Pollution Control Works," which was enacted in
1970 (Law 133, Dec. 25, 1970). The system is shown in Table 4. Figure 2 shows
the amount of sediments dredged and their costs since 1958.
The budget and the number of projects increased year by year. In the
fiscal year 1973 over one million cubic meters of sediment were dredged. After
the fiscal year 1974 public works projects decreased because the oil crisis
caused budget restrictions coupled with a steep rise in prices. Table 5 lists
six rivers where projects performed by the river control agency had a total
private cost-sharing of 12 million Yen.
The dredging projects which were performed entirely by private organi-
zations are shown in Table 6. These projects were related to dredging of sludge
and sediment which included toxic pollutants such as mercury and PCB. The total
amount of dredged material was about 140,000 m3, and the expenditures were about
10 million Yen.
13
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TABLE 1. IMPROVEMENT OF WATER QUALITY BY DILUTION
Clean Dilution Water
(Under Direct
Control)
The Tone River
The Kino River
The Yodo River
The Edo River
The Kiso River
The Maruyama River
The Hii River
The Umabuchi River
The Yoshino River
The Ohno River
(Grant- in- Aid)
The Hi no River
Sea
The Yodo River
River to be Purified
The Sumida River
The Waka River
The Neya River
The Naka River
The Arata River
The Tomaki River
The rivers in
Matsue city
The Umabuchi River
The Shinmachi River
The Ozu River
The old Kamo River
The Waka River
The Higashi Yokobori
River
Name of City
Tokyo
Wakayama
Osaka
Tokyo
Gifu
Tom i oka
Matsue
Hachinohe
Tokushima
Oita
Yonago
Wakayama
Osaka
Max. Water Intake
30 rnVsec.
8
20
20
6
5
7.2
10
10
4
1
10
natural inflow
Start of Construction
1964
1963
1968
1970
1972
1972
1972
1973
1974
1976
1972
1973
1975
-------
TABLE 2. POLLUTION CONTROL PROJECTS FOR RIVERS UNDER DIRECT CONTROL
Year
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
Budget Items
A
A
A
A
-
B
-
-
C
C
D
D
D
D
D
E
E
E
Name of River
Arakawa River (Sumida River)
same
same
same
-
same
-
-
Yodo River (Neya River)
same
same
Yodo River, Naka River
Naka River + 2 Rivers
Naka River + 5 Rivers
Naka River + 10 Rivers
Naka River +13 Rivers
Naka River + 14 Rivers
Naka River + 17 Rivers
Project
Iwabuchi Gate
same
same
same
-
Water Introduction
-
-
Water Introduction
same
same
same
Budget
20 x 106 Yen
30
30
10
-
1,150
-
-
320
1,030
1,640
720
Water Introd. & Dredging 723
same
same
same
same
same
1,449
1,261
1,339
1,479.2
2,208
Government
Share
2/3
2/3
2/3
2/3
-
2/3
-
-
1/4
1/4
1/4
1/4, 1/2
1/3
1/2
1/2
1/2
1/2
[Remarks] A
B
C
D
E
Pollution Control Budget for Direct Control Rivers
Budget for Reconstruction of Direct Control Rivers
Budget for Pollution Control Projects for Direct Control Rivers
Budget for Urban River Improvement Project for Direct Control Rivers
Budget for River Improvement Projects for Direct Control Rivers
-------
TABLE 3. POLLUTION CONTROL WORKS FOR GRANTS-IN-AID RIVERS
Year
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
Budget Items
A
A
A
A
A
A
A
A
A
A
A
B
B
B
B
B
C
C
C
Districts
Tokyo
Tokyo, Osaka
Tokyo, Osaka
Tokyo, Osaka
Tokyo, Osaka
Tokyo, Osaka
Tokyo, Osaka
Tokyo + 2 Districts
Tokyo + 3 Districts
Tokyo + 4 Districts
Tokyo + 4 Districts
Tokyo + 6 Districts
Tokyo + 9 Districts
Tokyo + 15 Districts
Tokyo + 24 Districts
Tokyo + 36 Districts
Tokyo + 47 Districts
Tokyo + 49 Districts
Tokyo + 52 Districts
Project
Dredging
same
same
same
same
same
same
Water Introd. &
Dredging
same
same
same
Budget
Government
Share
102 x io6 Yen 1/4
188
188
264
264
264
264
248
253
269
269
660
630
1,030
1,611
1 ,762
1 ,926
2,049
2,426
1/4
1/4
1/4
1/4
1/4
1/4
1/4, 1/3
1/4, 1/3
1/4, 1/3
1/4, 1/3
1/4, 1/3
1/4, 1/3
1/4, 1/3
1/2, 1/3
1/2, 1/3
1/2, 1/3
1/2, 1/3
1/2, 1/3
CTl
[Remarks] A Grants-in-Aid for River Pollution Control Expenditure
B Grants-in-Aid for Urban River Improvement Project
C Grants-in-Aid for River Improvement Project
-------
TABLE 4. RESPONSIBILITY FOR DREDGING AND DREDGING COSTS
Sediment Sources
Responsibility for Dredging
Responsibility for Expenses
(1) Numerous and
unspecified
(2) numerous and
unspecified
sources
+
specified
private
organizations
(3) specified
private organ-
izations only
river control agencies or
river Administrator
same as above
specified private organi-
zation
a) government shares
expenses with private
organizations
or
b) sole expenditure by
public organization
c) same as a) or:
d) shared by public and
private organizations
e) sole expenditure by
specified private
organization
XI08Yen
40
30
20
10
DIRECT CONTROL WORKS
GRANT AID WORKS
AMOUNT OF DREDGING
r-innnnnnnn
XI05m3
12
10
8
1958 60 62 64 66 68 70 72 74 76
Figure 2. Sludge and sediment dredging projects.
17
-------
TABLE 5. RIVERS WHERE DREDGING COSTS WERE SHARED WITH PRIVATE ENTERPRISE
^lame of City
Project
Total Budget (Yen)
Government
Share
Private
Share
Total
Tagawa River
Utsunomiya
Dredging
69,770 m3
100 x 106
20.8 x 106
10.06 x 106
30.86 x 106
Tenpaku River
Yokaichi
Dredging
16,920 m3
143 x 106
15.98 x 106
12.45 x 106
28.43 x 106
Tsusen River
Kurinoki River
Ni igata
Dredging
234,500 m3
400 x 106
131.804 x 106
268.196 x 106
400 x 106
Hama River
Nobaoka
Improvement
of stream
channel
2,900 m3
1 ,284 x 106
177 x 106
531 x 106
708 x 106
Omuta River
Omuta
Dredging
28,000 m3
Bottom
improvement
1,880 m3
471 x 106
100.51 x 106
370.49 x 106
471 x 106
River
lyo-Mishima
Dredging
10,790 m3
50 x 106
18.39 x 106
31.61 x 106
50 x 106
00
-------
TABLE 6. DREDGING PROJECTS PERFORMED ENTIRELY BY PRIVATE ORGANIZATIONS
River Class
Number of Local Gov-
ernments and Branches
of the Ministry of
Construction
No. of Rivers
Amount of Dredged
Sediments
Class A River
Controlled by
Government
Class A & B
River Controlled
by Local
Government
Total
4.6 x 104 m3
9.2 x 104 m3
13
17
13.8 x 104 m
4 m3
STANDARD FOR ADOPTION OF A RIVER POLLUTION CONTROL PROJECT
Government enforced River Pollution Control Project occurs when a river is
"seriously polluted." This classification is applied where:
a) Cleanup was already planned when the "River Environmental Standard"
was establi shed
b) Cleanup is planned as a Pollution Control Project based upon the Basic
Law of Environmental Pollution, Sec. 19
c) Sediments include excessive amounts of toxic pollutants such as
mercury, PBC, etc.
d) Water pollution is especially bad (BOD of 10 ppm or more)
SHARED EXPENDITURES FOR RIVER POLLUTION CONTROL PROJECTS
The basic rule states that necessary expenditures for pollution control
projects be paid by the person who discharged the pollutants. When the "person"
is a specified private organization, it has to perform the dredging by itself
under the approval of river control agencies. But in many cases pollution
control projects will be done by the river control agencies. This is because
the agency may conduct a flood control project concurrent to the pollution
control projects. Table 7 lists the government share of such pollution control
projects.
OUTLINES OF RIVER POLLUTION CONTROL PROJECTS FOR FISCAL YEAR 1977
The budget for River Pollution Control Projects in fiscal year 1977 is
shown in Table 8. Expenditures have increased 121% compared to 1976.
19
-------
TABLE 7. GOVERNMENTAL SHARE OF POLLUTION CONTROL PROJECTS
Share Ratio
Relevant Law
Direct Control Projects
Grant-in-aid projects in a
planning area of pollution
control
Grant-in-aid projects in other
areas
1/2
1/2
1/3
River Act
Art. 60, Paragraph 1
Law of Special Financial Aid
Concerning Pollution Control
Project
Art. 3, Paragraph 1
Law concerning Local Finance
Art. 16
TABLE 8. OUTLINES OF THE BUDGET FOR POLLUTION CONTROL PROJECTS IN THE FISCAL
YEAR 1977 AS COMPARED WITH 1976
1976 Fiscal Year
Number
of
River Amount Budget*
Direct Control Project
Sludge Dredging 9
Introduction of Clean 9
Water for Purification
Subtotal 18
Grant- in-Aid
Sludge Dredging 48
Introduction of Clean 5
Water for Purification
Total
Sludge Dredging 57
Introduction of Clean 14
Water for Purification
Total 71
157.3
157.3
654.3
811.6
811.6
603
1,065
2,208
1 ,776
650
2,379
2,255
4,634
1977 Fiscal Year
Number
of Increase
River Amount Budget* Ratio
8
12
20
52
5
60
17
77
152
152
792
944
944
610
2,102
2,712
2,244
609
2,854
2,711
5,565
1.012
1.310
1.228
1.264
0.937
1.200
1.202
1.201
* x lo6 Yen (300 Yen/dollar)
20
-------
Three channel construction projects for supplying clean water for river
purification have been adopted as new direct control projects by the government:
the Channel from the Sho River to the Uchi River (Toyama Prefecture), the
Channel from the Chikugo River to the Ikemachi River (Fukuoka Pref. ) and the
Channel from the Oyodo River to the Komatsu River.
New governmental grants-in-aid projects are five dredging projects: the
Goya River in the Class A Tone River (Tochigi Pref.), the Takada River in the
Class A Yodo River (Shiga Pref.), the Kawahara River in the Class A Hii River
(Shimane Pref.) and the Naka River in the Class A Bansho River (Oita Pref.).
LONG-TERM PLANS FOR RIVER POLLUTION CONTROL PROJECTS
Flood control projects began in the fiscal year 1977 as new five-year
projects. The total budget necessary for the projects is 7,630 billion Yen ($35
billion). In these five-year projects river pollution control is one of the
most important programs. The essential elements of the plans are as follows:
a) Promotion of river pollution control projects aimed at an improvement
of the river environment
b) Construction and improvement of sewage facilities in river basins
c) Enforcement of regulations regarding waste water quality
d) Promotion of the projects which have been planned under the "Pollution
Control Plan" to achieve the defined "Environmental Standard" in
certain areas
One of the long-term projects is to perform sediment dredging during the
early stages and to later construct canals for purification purposes. For
example, about 50 x 106 m3 of sludge and sediment have accumulated in the whole
country and about fifty rivers exist which can easily be cleaned up by building
channels to bring in clean water to help with purification.
The first project of the "Pollution Control Plan" started in December, 1970
and, since then, seven projects have been underway. The amount of sediments
dredged in the projects is shown in Table 9. The total amount of accumulated
sediments is about 12 x lo6 m3, and the total dredged amount up to the fiscal
year 1976 is about 1.8 x io6 m3. The percentage of total material to be dredged
is only 15% so far.
DISCUSSION OF RIVER POLLUTION CONTROL PROJECTS
CONFLICT OF NEEDS FOF FUTURE WATER RESOURCES
To move excess water from a large river with high water quality and
abundant streamflow into a small river with low water quality and small
streamflow is a common practice to purify the smaller river. Usually various
facilities (such as dams) will be constructed in the upper reaches of the larger
river to facilitate responses to downstream water demands. Equalization of the
streamflow will result and the number of possible days of excess water supply
21
-------
TABLE 9. SLUDGE AND SEDIMENT DREDGED UNDER THE POLLUTION CONTROL PLAN
Project
1st Project
2nd Project
3rd Project
4th Project
5th Project
6th Project
7th Project
Start Date
Dec 1,1970
Dec 12,1970
Dec 19,1972
Dec 18,1973
Dec 27,1974
Feb 17,1976
Jan 29,1977
Target
Year
1975
1975 or
1981
1976 or
1981
1977 or
1981
1978
1979 or
1981
1980
Required
Dredging
Volume
20.5
7,480
2,340
270
650
520
770
Total 12,050.5
Dredged
Volume
until
1975
20.5
1,190
210
14
70
30
—
1,345.5
Dredged
Volume
in 1976
—
170
40
5
40
30
150
435
103 m3
per cent
com-
pleted
by 1976
100%
18.2%
10.7%
7.0%
16.9%
11.5%
19.5%
14.8%
Place
Chiba, Ichihara, Yokaichi,
Mizushima
Tokyo, Kanagawa, Osaka, Saitama,
Arakawa, Chiba, the basin of the
Edo Riber, Kyoto, Nara, the
basin of the Yamoto River
Kashima, Nagoya, Eastern part of
Hyogo, Oita, Kita-Kyushu
Fuji, Southern part of Harima,
Otake, Iwakuni , Omuta
Tomakomai , Sendai Bay, Iwaki ,
Chiba seaside, Toyama, Takaoka,
Kinugawa, Nishi Mikawa, Kobe
Bigo, Shunan, Nanyo
Muroran, Hachinohe, Niigata,
Shizuoka Shimizu, Kyoto,
Okayama, Bizen, Wakayama, Ube,
Onoda, Shimonoseki, Hiroshima,
Kure, Takamatsu, Sakaide
Sapporo, Akita, Hitachi,
Matsumoto, Suwa, Gifu, Ogaki ,
Tohno, Eastern Mikawa,
Tokushima, Hyuga, Nobeoka
ro
ro
-------
will gradually decrease. Consequently there will have to be an adjustment
between the amount of water currently introduced and that of potential developed
water resources.
CONSERVATION OF DISPOSAL SITES FOR DREDGED SLUDGE AND SEDIMENT
The cost break-down for dredging is shown in Table 10. The cost will
depend highly on the conditions of the disposal site. Table 11 shows disposal
sites for dredged spoil in the fiscal year 1975. About half of the dredged
material is reclaimed in containment areas located at the ports. Recently
locating suitable disposal sites has become very difficult, and, the cost of
disposal areas for reclaimed sediment has risen year by year. For example, in
Tokyo Bay most of the dredge materials became reclaimed land masses. The
disposal fee (shown in Table 12) has more than doubled in recent years.
The offshore construction projects at Haneda, where dredged sludge and
sediment are now being disposed, will be finished in fiscal year 1977. After
completion, a waste treatment site outside the central breakwater is scheduled
to be built as a new disposal site. But, in Tokyo Bay, every year has seen the
number of available sites reduced and it has become difficult to construct large
areas of reclaimed land. Consequently, long term plans are necessary to provide
future diposal sites.
MEASURES TO PREVENT ENVIRONMENTAL IMPACTS
Measures should be taken to prevent secondary environmental impacts of
odor, noise, vibration, and so forth which result from the processes of dredg-
ing, treatment, transportation and disposal. The measures taken to date
include:
a) Water quality monitoring in and around the area of dredging and
disposal
b) Selecting a work schedule which minimizes conflict with fishing and
recreational activities
c) Redesign of construction machinery such as grab buckets and suction
dredges
d) Pollution control in dredging including use of sheet pile cofferdams,
sand bags, sheet protection, oil booms, etc.
e) Design of transport machinery such as improved dump trucks
f) Treatment of sediments by using chemicals such as coagulants or
solidifiers, dewatering sediments by using dewatering machines, sand
filters, or sand beds, and by covering disposal sites with asphalt,
grass or other plant materials
23
-------
TABLE 10. BREAKDOWN OF CONSTRUCTION EXPENDITURES
Dredging
Treatment
Construction of
Disposal Site
Disposal Fee
Mi seel laneous
Total
Direct Con-
trol Projects
30.6%
3.7%
35.5%
22.8%
0.1%
100.0%
Grants- in-
Aid Projects Remarks
31.5%
7.9%
24.7%
8.6%
18.3%
100.0%
Sludge transportation costs are
included in the case of pump
dredger
Costs of covering disposal site
are included.
Fee when sediments are disposed
on reclaimed land
Including seawall basement
TABLE 11. DISPOSAL SITE
Disposal Site
River Bed
Public Land
Private Land
Reclaimed Land
Total
Direct Con-
trol Projects
2
2
-
3
7
Grants- in-
Aid Projects
10
7
11
26
55
Total
12
9
11
29
62
Remarks
Planning area in park,
school , etc.
Forest, field, etc.
With or without fee
TABLE 12. PORTION OF DREDGED DISPOSAL FEES PAID TO THE TOKYO METROPOLITAN
GOVERNMENT
Fiscal Year
Unit Share Fee
(Yen/m3)
'ercentage of Share
Against Total Cost
1972
280
26%
1973
310
27%
1974
310
25%
1975
470
34%
1976
470
35%
1977
780
45%
24
-------
EXAMPLES OF RIVER POLLUTION CONTROL PROJECTS
THE SUMIDA RIVER
Water Quality
The Sumida River has been a main transportation route for centuries. The
history of the Sumida River is closely tied to that of the Tokyo metropolitan
area.
The River was the main stream of the Arakawa River until completion of the
Arakawa flood control channel in 1930. The water quality of the river was good;
there was abundant streamflow and the river supported a fishery and summer
recreational activities. About the end of Taisho era in 1925 industrial
development and an increase in population caused the water quality to
deteriorate rapidly except during the period just after the war.
The worst water quality in the river occurred in 1964. Since then, many
water pollution control projects have reversed this downward trend (see Figure
3). These projects include introduction of clean water from the Tone River,
construction of sewage facilities, enforcement of effluent limitations and
dredging of polluted sludge and sediments.
In 1975 the BOD value in the summer fell to 8 ppm or less in all places
except the Odai Bridge. But another index of organic pollution, the COD value,
remained high. At the Ryogoku Bridge COD was 9.3 ppm compared to 4.9 ppm BOD,
and COD was 11.7 ppm compared to 6.3 ppm BOD at the Shirohige Bridge, i.e. , COD
was approximately twice that of BOD. This phenomenon will be observed in any
river into which various chemicals are discharged or which has a slow flow rate
or in which a large amount of sewage has generated non-oxidable substances such
as nitrite, sulfite and miscellaneous organic materials not included in BOD.
For this type of river it is not always enough to assess organic pollution by BOD
value alone.
Outline of Dredging in the Sumida River
Studies (1,2) indicate that some BOD may be due to substances which
originate in sludge and sediment. If the elution rate of BOD substances is
proportional to the amount of sediment BOD, the removal of sediments may be
effective in river cleanup. From this point of view, the Tokyo Metropolitan
Government has dredged in the Sumida River since 1958.
DREDGING OF LAKE KASUMIGAURA
Lake Kasumigaura is located at the southeastern end of the Kanto Plains.
It has about 220 square kilometers of surface area and a shoreline of about 250
kilometers. The lake is the second largest in Japan (next to Lake Biwa) with a
maximum water depth of seven meters and an average depth of four meters. Two
projects are currently being conducted—one is a levee project for flood
prevention and the other is a water resource development project to cope with
increasing demand for water in metropolitan areas.
25
-------
600
500
400
300
200
100
0
0
10
20
30
40
50
60
40
30
20
10
I 1 I I I I I I I I I T
I I T
AMOUNT OF DREDGING
AMOUNT OF
WATER INTRO-
DUCED INTO
THE SUMIDA
RIVER
BOD VALUE AT
SHIROHIGE
BRIDGE
I |_ I I I I I 1 I I I I I I 1 I I
1958 60 62 64 66 68 70 72 74
Figure 3. Water quality, amount of dredging and amount of clean water introduced
for purification of the Sumida River.
26
-------
The lake's water quality has recently deteriorated (Figure 4). In 1972 the
Environmental Standard for Lake Kasumigaura was set at Classification A-CC (COD
3 ppm or less), the interim classification was B (COD 5 ppm or less). Pollution
sources for the lake are domestic, industrial and livestock wastewater plus a
relatively large amount of pollutants from bottom sediments generated by the
lake itself. To clean up the lake the Ministry of Construction surveyed the
sediments and authorized the dredging of 1.2 x 106 m3 of sediments. About
300,000 m3 of sediments are planned to be dredged by 1982.
10.0
o>
E.
Q
O
O
2,0
I l i i
[ill
"Tentative Environment
- Standard 5 ppm"
"Environment
Standard 3 ppm"
l l l I I l l l I
1.5
1967 69 71 73 75
o
"2L
UJ
a.
CO
1.0
a:
0,5
I l
I I I I I I I I 1 I I
1967 69 71 73 75
Figure 4. Water quality variation at Lake Kasumigaura.
A large amount of water for agricultural and urban use is drawn from Lake
Kasumigaura, but the lake is also used for fishing and recreation. Thus, there
are many factors to be considered in dredging and attention should be paid to
possible sources of secondary pollution.
The dredge Kasumi-Go was developed especially with this in mind. It is
practical from standpoints of both economics and pollution control. The
dredge's specifications are shown in Figure 5.
Special features are:
a) no generation of secondary pollution while dredging
b) feasibility of collecting large amounts of sludge and sediment
c) no special disposal areas required
d) no treatment required for discharged effluents
27
-------
Dredging Capacity: Dredging Depth 5 m below water surface
Rated Capacity 60 mVhr
Working Distance 30 - 150 m
Sludge Sampling Equipment:
Capacity 0.5 m3 x 2 units
Diameter of delivery pipe; 105 mm
Type of Valve: bevel valve/ball valve
230 PS < 1 ,800 rpm
180 KVA
Capacity: 7 mVmin x 7 kg/cm2
Motor: 15 KW x 440 V
Capacity: 72 mVmin x 7 kg/cm2
Motor: 55 KW
Winch: Three Drum Type x 2 units
Intake & Delivery Pump: 0.36 mVmin. , 0.22 nrVmin
Generator:
Vacuum pump:
Compressor:
Figure 5. Outlines and specifications of sludge dredger, Kasumi-Go.
28
-------
Various studies and tests on reuse of spoils dredged have been conducted for
land reclamation or for bank filling.
REFERENCES
1. Murakami, Hasegawa, et al. Influence of Sediments at River Beds to River
Water Quality and Dredging Efficiency for Water Pollution, Prepared by
Civil Works Research Center, Research Report 11-6.
2. Dredging Efficiency of Water Pollution. Prepared by Seven Local Gov-
ernments' River Section of Construction Bureau and Water Quality Section of
National Environmental Research Center, 1970.
29
-------
TURBIDITY GENERATED BY DREDGING PROJECTS
Osamu Nakai
Environmental Protection Division
Bureau of Ports and Harbors
Ministry of Transport
SUMMARY
This paper discusses investigations into turbidity generated by dredging
during port construction. The study was made by the Bureau of Ports and Harbors
and the Port and Harbor Research Institute, Ministry of Transport from 1973 to
1976.
Field investigations were conducted to develop a method for predicting the
quantity of turbidity generated by various dredges in different kinds of soil.
A turbidity generation unit (TGU) was calculated using the results of these
field investigations. It is defined as the quantity of turbidity generated per
unit volume of dredged material, and can be effectively used to predict the
quantity of turbidity.
INTRODUCTION
Marine transportation in the coastal areas of Japan has been common for
centuries. There are currently more than one thousand ports and new port
construction projects are still going on. This work affects the marine en-
vironment and can cause serious problems.
The coastal areas have also been used as fishing grounds since ancient
times. The turbidity generated by current port construction, although limited
in space and time, is confined to specific areas of which ten are fertile
fishing grounds.
The impact of turbidity on the fishery is usually negative because
turbidity may cause the following undesirable phenomena:
(1) Decreases of photosynthesis in phytoplankton due to decreased
transparency
(2) Interference with fish feeding on benthos
(3) Interference with respiration of fish
(4) Decreased habitat area for fish
(5) Negative effects on esthetic quality because of the muddy water
31
-------
In addition to these problems, toxic substances
dredged sediments along with the turbidity.
may be released from the
To deal with these problems, the Bureau of Ports and Harbors and the Port
and Harbor Research Institute, Ministry of Transport, conducted field investi-
gations from 1973 to 1976 to determine the quantity and diffusion character-
istics of turbidity generated by various types of dredges in several kinds of
soil.
These investigations do not study the problem of soil contaminated with
toxic substances. This is addressed in a Tentative Guideline for Managing
Contaminated Bottom Sediments which was promulgated by the Environmental
Agency in 1974. Part of the solution was to use special cutterless pump
dredges developed to lessen the quantity of turbidity generated. Canvas
shrouds are also set around the dredge to localize the turbidity. The Tenta-
tive Guideline also points out the importance of monitoring water quality and
fish during the dredging period.
INVESTIGATION OF TURBIDITY GENERATED BY DREDGING
CONCEPT OF THE TURBIDITY GENERATION UNIT
The mechanism of generating turbidity by dredging is different for each
type of dredge. The diffusion of suspended material is influenced by tidal
current, grain sizes and other soil conditions as well as the irregularities
in the dredge action and bottom configuration. Figure 1 shows a schematic of
the process of turbidity generation.
TIDAL CURRENT-
ORIGIN OF
TURBIDITY-
-ZONE OF RESUSPENSION
^ZONE OF SEDIMENTATION
Figure 1. Generation mechanism of turbidity.
In this paper turbidity is defined as the mass of suspended solids. The
quantity of turbidity is assumed to be proportional to the quantity of dredged
materials. Therefore:
W0 = CW.
(1)
32
-------
where,
W0
C
W
total quantity of turbidity generated by dredging works (ton)
a coefficient dependent on dredge type, soil condition, etc.
total quantity of dredged materials (ton)
To simplify the process of estimating turbidity, the concept of a tur-
bidity generation unit (TGU) was introduced. This stands for the quantity of
turbidity generated when a unit quantity of bed material is dredged under a
standardized condition. The method of standardizing the TGU is as follows:
A standard tidal current velocity is determined by the
condition that soil particles with diameters larger than
(silt) are not resuspended. This leads to the relation:
W = K-W0/Q =
(2)
where,
W =
Qs =
Y =
K =
R74=
turbidity generation unit (ton/m3)
volume of dredged materials (m3)
specific weight of dredged materials (ton/m3)
R?4/Ro
fraction of particles with a diameter smaller
fraction of particles with a diameter smaller
than
than
74u
the
diameter
of a particle whose critical resuspension velocity equals the
current velocity in the field.
W0,C=as in equation (1)
Critical resuspension velocity
under which a specific particle is
particle diameter and
or Camp's equation. Table 1 gives
from these equations.
is defined as the minimum current velocity
not resuspended. The relationship between
critical resuspension velocity depends upon Ingersol's
some of those relationships as derived
TABLE 1. RELATIONSHIP BETWEEN DIAMETER OF SOIL PARTICLE AND CRITICAL
RESUSPENSION VELOCITY
Classification
of Soil
clay
silt
fine sand
rough sand
Particle Size
(mm)
•v 0.005
0.005 -v 0.074
0.074 -v 0.42
0.42 -v 2.0
Critical Resuspension
Velocity (cm/sec)
•v 0.03
0.03 -v 7
7 -v 15
15 -v 35
Equation used for
Derivation
Ingersol
Ingersol
Camp et al .
Camp et al .
When the tidal current velocity in
calculated using the following procedure:
the field, Vco, is given, W can be
33
-------
(1) the diameter of particle d0, which has a critical resuspension
velocity Vco, is determined from the lower curve in Figure 2.
(2) R0 is also determined from Figure 2 using the upper curve of cumula-
tive particle size for sediments in the field.
(3) W0 and Qg are gained from field investigation and W is then calcula-
ted according to equation (1).
Particle Size
(mm)
Eq. of Ingersol
Eq, of Camp et. al.
Figure 2. Method of standardization of turbidity generation unit.
FIELD INVESTIGATION METHODOLOGIES
To determine the TGU, many field investigations were made at many ports.
The following methodology was developed after much experience.
(1) Water Sampling Stations
Water sampling stations should be arranged in straight lines orthogonal to
the direction of the tidal current but taking into consideration the velocity of
the tidal current and the area of dredging. Figure 3 shows an example of the
arrangement of stations. The lines are arranged for the following purposes:
34
-------
1 i ne I
line II -
line III
to measure the background turbidity value
to measure the generated turbidity and
check the coefficient of diffusion
to check the quantity of turbidity measured
at line II and to check the coefficient
of diffusion
I S
Tidal Current
Figure 3. Arrangement of turbidity measuring stations.
The vertical arrangement of water sampling stations depends on the water
depth. When the water depth is approximately 10 meters, three water levels
should be sampled. Figure 4 shows an example of the vertical arrangement.
i
H
1
tSOcm - '
CM
n
i
H
2
1 50 cm
Figure 4. Vertical arrangement of sampling points.
Since the direction and the velocity of the tidal currents are very
important factors, preliminary investigation should be done to determine them
before the dredging begins. This is necessary to find out whether or not
35
-------
turbidity generated by the dredge will be detected at the selected sampling
stations.
(2) Water Sampling
The mass of suspended solids in the water samples is measured to estimate
the turbidity generation unit. Each water sample should be taken simultaneously
at all points and at short intervals during the dredging. Though the interval
of water sampling is often restricted by working conditions, there should be at
least one hour of continuous sampling at 10 minute intervals. If possible, it
is best to calculate the quantity of turbidity by integrating continuously
measured values.
(3) The particle size distribution of the bottom sediment must be measured
prior to dredging operation.
(4) Tidal Current and Water Depth
The direction and the speed of the tidal current are important factors
in estimating the turbidity generation unit and they should be carefully
measured. Better results can be obtained from a large number of samples so
measurements should be made at two or more points for each of the three depth
layers. Since water depth changes gradually due to the tide, it should be
measured simultaneously with each water sample.
(5) Aerial Photographs
Aerial photography can be used to calculate the coefficient of diffusion
and obtain the diffusion pattern. Photographs should be taken simultaneously
with the water samples.
(6) Volume of Dredged Materials
Measurement of the volume of dredged materials is the most important factor
in estimating the turbidity generation unit. The method is different for each
type of dredge. For example, with a pump dredge, volume can be obtained by
measuring both the soil concentration and volume of interstitial water.
(7) Position of Dredge
In dredging using pump dredges or bucket dredges the position of the
turbidity source changes every moment and therefore, the position should be
recorded with respect to time.
METHOD OF ANALYSIS
There are many methods for estimating the quantity of turbidity generated
by a dredge from measured data. Two typical methods are discussed—the water
sample method and the use of aerial photographs.
(1) Calculating the quantity of turbidity passing through a line of water
sampling points is the method used in this paper. Figure 5 shows an
36
-------
example of the arrangement of water sampling sites in a field investi-
gation.
This is the method used in this paper. The total quantity of turbidity
can be calculated as follows:
The net concentration of suspended solids (SS) generated by dredging, S,
is defined as:
S = S' - SQ (3)
where,
S = net concentration of SS generated by dredging
S' = concentration of SS measured in the field during dredging
S0 = background concentration of SS
The total quantity of turbidity generated by dredging W can then be
calculated using the formula: °
W0 = IA-U-S (4)
where,
W0 = total quantity of turbidity (mass of suspended solids)
generated by dredging
A = area of section concerned
U = tidal current velocity
S = net concentration of SS measured in the field during dredging
(2) Measuring the width of turbid water using aerial photographs.
The width of the turbid water area taken by aerial photographs only shows
the surface layer. If the width of the turbid water area is assumed to be
nearly equal from surface to bottom, the total quantity of turbidity, W0,
can be calculated by the relation:
W0 = B-H-U-S (5)
where,
W0 = total quantity of turbidity (mass of suspended solids)
generated by dredging
B = width of the turbid water area as measured by the aerial
photographs
H = depth of water
U = tidal current velocity
S = net concentration of SS generated by dredging
37
-------
Tidal Current
O
err
o
E
o
ro
o
o
/ c
c
30m
\u/
) *
r c
50m 1
E
O
.2.
~ 30cm
Section
JH
2
50cmT°
H
Osample point
Pump Dredger
Figure 5. An example of a field arrangement for water sampling.
RESULTS AND CONCLUSIONS
Table 2 shows the results of investigations using method (1) which
calculates the turbidity from water samples passing through a line of points.
Turbidity generation units in Table 2 are normalized to the standard velocity
of about 7 cm/sec (see Figure 2). Dredge type, horsepower or bucket volume
and dredged material classification are factors affecting the magnitude of
the generation unit. But, judging from Table 2, the horsepower or bucket
volume does not seem to be as significant a factor as the other two. Tur-
bidity generation units are therefore discussed only in relation to the type
of the dredge and the kind of material dredged.
The
Table 2.
following general characteristics of the TGU can be concluded from
The TGU varies with different dredged materials. For example, the TGU
for a pump dredge is in the vicinity of 40 kg/m3 for clay but only
around 0.2 kg/m3 for sand. For a grab dredge, the TGU
kg/m3 for clay and around 15 kg/m3 for silty loam. In
smaller the particle size, the larger the TGU.
is about 84
general, the
2) There are enough data to compare the TGUs for clay among the three
types of dredges: the pump dredge, grab dredge and trail ing-suction
dredge. The TGU value of 25 kg/m3 is the smallest for the trail ing-
suction dredge. The other values are 35 kg/m3 for the pump dredge
and 84 kg/m3 for the grab dredge.
Turbidity generated by several dumping projects was investigated in
addition to the studies on dredge-generated turbidity. The TGUs for dumping
are calculated using the same method as for dredging. Some of the results are
shown in Table 3.
38
-------
TABLE 2. TURBIDITY GENERATION UNITS FOR DIFFERENT DREDGES AND DREDGING
PROJECTS
Type of
Dredge
pump
trai 1 ing-
suction
grab
bucket
Power or
Bucket
Vol ume
4,000 HP
2,500 HP
2,000 HP
2,400 HP
x 2
1,800 HP
8 m3
4 m3
3 m3
Dredged Materials
d*<74p
99.0 %
98.5
99.0
31.8
69.2
74.5
94.4
3.0
2.5
8.0
92.0
88.1
83.2
58.0
54.8
45.0
62.0
87.5
10.2
27.7
d*
-------
TABLE 3. TURBIDITY GENERATION UNITS FOR DUMPING PROJECTS
Type of
Oredge
barge
trai 1 ing
suction
Barge
Volume or
Generating
Power
500 m3
180 m3
120 m3
2,400 HP
1 ,800 HP
Dumped Materials
d <74u
36.5 %
21.5
20.5
2.7
57 7
22.7
19.1
68.6
82.2
d <5u
13.0 %
10.0
15.0
27.5
6.8
19.4
33.4
Classification
silty loam
silty loam
silty clay loam
sand
silty clay loam
sandy loam
sandy loam
silty loam
clay
Generation Unit
kg/m3
14.9
15.8
10.6
0.02
8.3
3.8
143.5
22.7
123.4
THE RELATIONSHIP BETWEEN GENERATED TURBIDITY AND DREDGE OPERATING FACTORS
The work discussed in the previous section was performed under standardized
dredge operating conditions. In the field, the conditions which influence
dredge operation are quite variable. The influence of these factors on the
generation of turbidity must be known in order to apply this analysis to actual
field projects. In this section, the relationship between turbidity and
dredging operating factors for the pump dredge and grab dredge are discussed.
PUMP DREDGE
On the pump dredge the studies were made with the dredge operating
factors shown in Table 4.
TABLE 4. PUMP DREDGING OPERATING FACTORS
Test No.
Ci
C2
C3
C4
C5
C6
C7
Cutter's Revolutions
Per Minute
18
18
18
18
18
18
0
Swing Speed
(m/min. )
6
8
10
6
8
10
6
Thickness of
Dredged layer
large *
large
large
small **
smal 1
smal 1
smal 1
* "large" means about 1.5 m in thickness
** "small" means about 0.8 m in thickness
40
-------
Following are the results of tests made under these seven conditions.
(1) Dredging capacity
Dredging capacity seems to _dep_end upon average dredging thickness, ts>
and average swing speed, V , so t -V is given as a parameter for estimating
dredging capacity.
As shown in Figure 6, the concentration of dredged materials, x, is
nearly proportional to t -V .
according to the formula:
= 45.5
The relationship between them can be described
(6)
where,
x = concentration of dredged materials (%)
D = maximum diameter of cutter (cm)
V = standard swing speed ( = 8 cm/sec.)
t = average dredging thickness (m)
= average swing speed (m/min)
V
40
Figure 6. Relationship between pump dredge operating factors and concentra-
tion.
(2) Distribution of turbidity
To analyze turbidity generation the distribution of turbidity around the
cutter head of the pump dredge was obtained as shown in Figure 7. Points A
and B show sampling points on both sides of the cutter. Turbidity is greater
at point A than at point B. This difference seems to be related to the revo-
lution of cutterhead.
Figure 8 shows the vertical distribution of turbidity. From this figure
it is clear that turbidity is higher in the lower layer (10 m below the sur-
face) than in the upper layer (0.5 m below the surface). In comparing the
differences according to dredging thickness, the thicker the cut, the more
turbidity is generated.
41
-------
• 8
• OO
o o oo o
0 ° o..
I I I I 11
I I I Mil;
• 1st Test
o 2nd Test
466 O1 2 468
TO it A (ppm)
Figure 7. Turbidity around cutterhead.
DPP-
e a v
* e a »' 2
To «i A (Ppm)
Figure 8. Vertical distribution of turbidity around cutterhead (Cl to C3:
thickness ~ 1-5 m C4 to C7: thickness *• 8 m).
42
-------
(3) Relationship between turbidity and dredging operating factors for the
pump dredge
The quantity of materials dredged can be calculated from the moving
distance of the dredge, depth of cut, and swing speed. If dredged materials
are all taken in through the suction head, the concentration of dredged mater-
ials, X , in the delivery pipe is given as:
. = 1 -T -V -/15nD2V (7)
C a S S
where,
1 = arching distance of head for one swing (m)
t = depth of cut for one swing (m)
D = diameter of delivery pipe (m)
V = swing speed (m/min.)
V = flow velocity in delivery pipe (m/sec.)
In reality not all of the dredged materials are taken in through the
suction head. Some remain at the dredge site and some are suspended in the
water. If we use X as the actual measured concentration of dredged materials
in the delivery pipe, then the effective sucking ratio is expressed as X/X
and R, the ratio of non-sucked soil to total soil dredged, is defined as:
R = 1 - / (8)
and the cumulative ratio of soil, R', is defined as
yy
R' = 1 - f£ (9)
c
Figure 9 shows the relationship between R' and the concentration of
suspended solids. Figure 10 shows the relationship between R' and V /V
Using these curves we can derive the best dredge operating factors to use
with a given soil concentration to control turbidity. For example, if the
concentration of suspended solids is to be less than 100 mg/1, suitable dredg-
ing conditions and the value for the concentration of dredged materials can be
calculated as follows.
From Figure 9 the value of R' must be in the range 0.15 ~ 0.20. Using
this result with the curve in Figure 10 leads to the requirement that the value
of V /V should be 1.2 -v 1.4_. When t /D is set at 0.58-v 0.59 the concentra-
tion5 ofsodredged materials, x, is 31 s~ 'SG % as determined by equation (6).
These are then the required operating factors:
net dredging thickness (m) 6.4 ~ 6.5
dredging thickness per swing (m) 1.60 ~ 1.63
swing speed (m/min.) 9.6 ~ 11.2
concentration of dredged materials (%) 31 "» 36
43
-------
0
I" ISO
40
N\
Ten HP CNv
X >*j-
'
/•V^
Vfiter '-7.
OJO Oft 020 02 OJD
Figure 9. Relationship between R' and concentration of SS.
03
W0.2
or
fi/Dc=0 58-0.59
W 08 12 16
Figure 10. Relationship between swing speed and R1
44
-------
GRAB DREDGE
For the grab dredge similar calculations were made using the dredge
operating factors in Table 5.
This study showed that the turbidity generated by a grab dredge depends
upon a parameter, P, where P = (weight of grabbed materials per cycle) x
(hoisting speed). Figure 11 and Figure 12 show the relationship between
maximum turbidity and P, and between average turbidity and P, respectively.
These figures imply that there is an optimum value of P which will minimize
the turbidity generation.
TABLE 5. DREDGE OPERATING FACTORS
Test No.
Hoisting Speed (m/sec.)
Dredging Thickness
Cj 1.29
C2 1.29
C3 0.83
C4 0.83
large *
small **
large
smal 1
* "large" means that the entire volume of the grab bucket is filled.
** "small" means that half the volume of the grab bucket is filled.
500
400
|300
2 20°
,5
too
\
'3 4 5 6 7 8 9 K> 11
Figure 11. Maximum turbidity vs. P.
( 0
tr\
10
A
k
^N-
VA
\
V
/
s
,
j
/
/
/ »
^'
A
/
/X
f'
,^
<±
1-S*«
ca»*
P (loom/*)
Figure 12. Average turbidity vs. P.
45
-------
APPLICATION OF THE RESULTS
The results of these investigations are applicable in the following
situations.
(1) Application to environmental impact assessment of construction projects.
The change in concentration of turbidity around a construction site can
be predicted using the turbidity generation unit as input data in a simulation
model of diffusion.
(2) Design of a water quality monitoring system for use during construction
projects.
The TGU and the relationship between dredge operating factors and turbid-
ity are useful in deciding where to place monitoring points, and what the
required measuring range of the apparatus should be.
(3) Determination of optimum dredging operating factors
These investigations show that there is an optimum set of dredge opera-
ting factors which minimize the turbidity generation.
REFERENCES
1. The 4th District Port Construction Bureau, Ministry of Transport. In-
vestigation of the influence of turbidity caused by dredging works.
1976.
2. Yokuji Yagi et al. Influence of Operating Condition against Dredging
Capacity and Turbidity. Technical Note of Port and Harbor Research
Institute. No. 228 Sept. 1975.
APPENDIX I
SUSPENDED SOLIDS (SS)
Suspended solids are those substances which can be separated by filtra-
tion or by means of a centrifugal separater. SS is defined as the concentra-
tion of suspended solids in water and is commonly used as an index of the
turbidity level of water. There are quantitative methods of measuring SS, and
the Japanese Industrial Standard (JIS) prescribes the following two methods:
1. FiItration Method
This method determines the suspended solids by filtering the water
sample and weighing the filtrate. There are two kinds of filtration methods -
the Sintered Glass Filter Method and the Buchner Funnel Method.
SS can be obtained from the following formula:
46
-------
S = (a - b)-l,000/V (Al)
where,
S = suspended solid concentration (mg/1)
a = difference in weight of the test water before and after filtra-
tion (mg)
b = difference in weight of the filtrate before and after filtration
(mg)
V = volume of test water (ml)
2. Centrifuge Method
This method separates suspended solids from the test water under centri-
fugal force. It is primarily used with water samples containing very fine
suspended sol ids.
Concentration of suspended solids can be obtained by following formula:
S = a-l,000/V (A2)
where,
S = concentration of suspended solids (mg/1)
a = difference in weight of the test water before and after cen-
trifugation (mg)
V = volume of test water (ml)
APPENDIX II
TURBIDITY
The Japanese Industrial Standards (JIS) prescribe methods for measuring
turbidity where a unit of turbidity of 1 ppm is defined as the level of tur-
bidity of 1 liter of water containing 1 mg refined Kaoline.
1. General Method
This simply compares the sample by eye with a series of standard solu-
tions containing refined Kaoline.
2. Photoelectric Photometer Methods
There are two methods which use a Photoelectric photometer. One measures
the percent of 660 m|j light passing through the sample, and the other measures
the light scattered by the small particles contained in the water sample.
47
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RECENT PROGRESS IN TECHNIQUES FOR MANAGING
CONTAMINATED BOTTOM SEDIMENTS
Hiroma Koba
Japan Dredging and Reclamation
Engineering Assocation
SUMMARY
This paper provides a brief introduction to recent progress on management
techniques for contaminated bottom sediments. It includes comments on the
Technical Guideline prepared by the Japan Dredging and Reclamation Engineering
Association (hereafter referred to as the JDREA).
INTRODUCTION
In Japan many ports, rivers, lakes and marshes possess contaminated bottom
sediments which create undesirable effects on the surrounding environment. The
pollutants in these bottom sediments are traced to waste from manufacturing
plants or mine tailings (such as in Tagonoura Port or Minamata Bay), urban
sewage, agricultural effluents and other industrial or urban sources.
The most effective solution to the problem is to control pollution at the
original source, but this is usually very difficult or impractical. Therefore,
the management of contaminated bottom sediments has to be implemented in
conjunction with countermeasures taken directly at the sources. Thanks to
strict enforcement of legal restrictions on effluents at their origin it is
likely that accumulation of contaminated sediments will decrease in the future.
Meanwhile, some extreme cases of bottom pollution must be dealt with
immediately. The increased level of management in Japan has encouraged devel-
opment of new techniques in this field. To establish new criteria the JDREA has
been engaged, under the sponsorship of the Japanese Government, in the
formulation of a Technical Guideline on continual management of bottom sedi-
ments. In the following sections the current status of the management tech-
niques are presented. Many of the updated techniques were developed as stated
in our review of the Guideline during the 1976 conference.
PLANNING TECHNIQUES
REMOVAL CRITERIA
The government has set tentative criteria for sediments contaminated with
mercury and PCB. In the case of mercury, any contaminated deposits exceeding a
49
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density of 25 ppm mercury in rivers or marshes are subject to removal. In marine
areas removal standards have to take into account certain marine phenomena and
other related factors before the final decision for removal is made. A more
precise method is needed for comparing sea waters with rivers. Table 1 shows
examples of Government-set standards for mercury which led to removal projects
in certain areas. They serve as useful references for setting up new criteria
i n the future.
TABLE 1. EXAMPLES OF CRITERIA FOR REMOVAL OF MERCURY-CONTAMINATED SEDIMENTS
Area
Tokuyama Bay
Minimata Bay
Dohkai Bay
Mizushima Port
Criterion (Mercury-ppm)
> 15
> 25
> 30
> 36
The same areas in Table 1 have a standard for PCB which specifies that
deposits contaminated with over 10 ppm PCB (per weight of dried sediment) must
be removed.
No toxic substances other than mercury and PCB are covered by the official
tentative standard.
Dominant pollutants in Japan are not always limited to these two substances
and consequently other standards are needed for other toxic materials. Because
of increased interest in bottom-sediment management the impetus for a new
standard has increased, and the JDREA has responded with the Technical Guideline
presented in this paper.
The JDREA1s Technical Guideline classifies contaminated bottom sediments
into three types: toxic substances, organic sediment, and oily sediments.
Toxic Sediments
Some toxic substances are specifically identified in the Technical Guide-
line (Table 2). The sediments are considered toxic when the solute concentra-
tion in a solubility test is greater than the indicated value. According to an
interim Government manual, the condition designated in Table 2 is necessary but
not sufficient for justifying removal. It is needed to establish a removal
situation but an individual technical judgment is also required.
Some local governments have their own standards which are more detailed
than those of the national government. Table 3 lists the standards set in
Yokohama City.
50
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TABLE 2. CRITERIA FOR JUDGING TOXIC SEDIMENTS
Toxic Pollutant
Alkyl mercury
Mercury
Cadmium
Lead
Organic phosphorus
Hexivalent chromium
Arsenic
Cyanide
PCB
Measured Concentration from the Solubility Test
detectable only
0.005 mg/1
0.1 mg/1
1.0 mg/1
1.0 mg/1
0.5 mg/1
0.5 mg/1
1.0 mg/1
0.003 mg/1
TABLE 3. EXAMPLES OF CRITERIA FOR REMOVAL OF TOXIC SEDIMENTS AT YOKOHAMA
Soil Type
Sandy
Silt, c 1 ay
Organic
Toxic substance (ppm)
Total
Cyanide Mercury Cadmium Lead Chromium Arsenic
1.2
2
3
1.2
2
3
24
4
6
240
40
60
24
40
60
6
10
15
Organic Sediments
Sediments with a significant amount of ignition loss* are defined as
organic sediments, according to the JDREA's Technical Guideline. Sediments
polluted with organics have a negative
ways:
influence on the environment in three
(1) They reduce oxygen concentrations which threaten
shellfish.
the 1ife of fish and
(2) Phosphorus and nitrogen are released which causes eutrophication.
(3) Hydrogen sulfide is released under anaerobic conditions causing odors
and other problems. No official criteria has been set with regard to
organic sediments.
In the meantime, local port management agencies are attempting to set up
their own removal criteria to cope with the organic pollution of sediments. The
Technical Guideline lists these local criteria as a reference. One example is
given in Table 4 for Nagoya Port management agency. If any two of the three
criteria are met, then the sediments should be dredged and disposed.
low fraction of ash-free dry weight.
51
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TABLE 4. CRITERIA FOR REMOVAL OF ORGANIC SEDIMENTS AT NAGOYA PORT
Item
Loss on ignition
COD
Sulfide
Standard
over
over
over
10%
20 mg/g
1 mg/g
Oily Sediments
The accumulation of sediment contaminated with oil is a major problem.
Oi1-contaminated fish have a bad odor which is usually caused by mineral oils.
But sediments contaminated with organically-derived oils may be dangerous
enough to kill fish and shellfish if they are highly concentrated. Oily
sediments might well be classified with the organic sediments (see above).
Taking this point of view, the Technical Guideline classifies sediments with a
high density of normal hexane extractions as oily sediments.
For the time being, establishment of removal criteria for oily sediments is
left to the technical judgment of the parties concerned. Since there is much
less data available as managment examples for oily sediments, the Technical
Guideline contains only the two actual cases given in Table 5. There is still
room for improvement of these techniques.
TABLE 5. EXAMPLES OF REMOVAL CRITERIA FOR OIL SEDIMENTS
Water Area
Mizushima Port
Yokkaichi Port
Yokkaichi Port
Criteria for Removal (Density of normal
2,000 ppm
4,000 ppm
2,000 ppm (mineral
hexane
oils)
extractions)
Incidentally, the Japan Marine Resources Protection Association is of the
opinion that the standard density of normal hexane extractions should be reduced
to below 1,000 ppm.
SECONDARY POLLUTION CAUSED BY REMOVAL AND DISPOSAL OPERATIONS
The management work may sometimes temporarily increase turbidity. It is
important to prevent this, especially if the sediments are toxic. It requires
the latest techniques to be able to judge to what extent temporary turbidity
caused by such operations must be controlled.
The criteria for monitoring water quality during the management operations
are decided by the Government. Table 6 is the official standard for toxic
substances in water.
Table 7 contains general criteria applicable to water quality during
management operations where special consideration is given to the seafood
52
-------
products industry. These criteria have more severe standards, depending on
particular conditions. Therefore, any technical judgment will actually depend
on the parties concerned.
Various reference data are inserted in the Technical Guideine for the
purpose of formulating criteria applicable to water quality during management
operations. For instance, the influence of suspended solids on fish and
shellfish are stated in Table 8 and the correlation between oil concentration in
sea water and occurrence of malodorous fish is given in Table 9.
TABLE 6. CRITERIA FOR MONITORING WATER QUALITY DURING DREDGING AND DISPOSAL
(PART 1)
Toxic Substance
Standard
Cadmium
Cyanides
Organic phosphorus
Lead
Hexivalent chromium
Arsenic
Total mercury
Alky! mercury
PCB
less than 0.01 ppm
not detectable
not detectable
less than 0.1 ppm
less than 0.05 ppm
less than 0.05 ppm
less than 0.0005 ppm
not detectable
not detectable
TABLE 7. CRITERIA FOR MONITORING WATER QUALITY DURING DREDGING AND DISPOSAL
(PART 2)
Water Qua! i ty
PH
COD
DO
Standard
7.0 8.3
less than 8
over 2 ppm
ppm
TABLE 8. EFFECTS OF SUSPENDED SOLIDS ON FISH AND SHELLFISH
Fish and Shellfish
Prawn
Immature yellowtail
Red sea bream
Pearl oyster
Suspended Solids (ppm)
over 50
over 20
over 100
over 7
Observation
existence hampered
existence hampered
flutter frantically
water absorption
changed
53
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TABLE 9. EXPOSURE TIME AND OIL CONCENTRATION CAUSING FISH FLESH ODOR
PROBLEMS
1
Oil
Light oil
i
i
l
Fish
Saurel
Hours exposed
2 hours
24 hours
Oil concentration
0.43 ppm
0.043 ppm
DREDGING TECHNIQUES
GENERAL DESCRIPTION
The Government is now administering the dredging of accumulated sedi-
ments. According to official requirements an ocean area is divided into two
sections; one is the minimum operative area within which temporary turbidity
due to dredging is unavoidable, the other is the area which must be protected
from the dredging operations. Thus, attention must be paid to water quality
along the boundary line so turbid water does not enter the side to be kept
clean. Techniques for dredging bottom sediments have been developed which
place primary emphasis on minimizing turbidity while still maintaining dredg-
ing efficiency. A secondary emphasis has been to dredge all materials in a
given area and to have dredged material contain a high concentration of sol-
ids.
The technical developments on these approaches are touched on in the
Technical Guideline, but further research is strongly advised, since many
difficult problems are left unsolved.
CLASSIFICATION OF DREDGING TECHNIQUES
Advanced dredging techniques have been tailored to dredging specific
bottom sediments. The Technical Guideline shows 32 dredges, each equipped
with special devices for specific sediments. These are shown in Table 10.
PUMP DREDGES
Dredges in groups A, B and C in Table 10 use pumps. Hopper dredges in
group A have suction heads suitable for dredging contaminated sediment. Few
examples of the performance of this type of dredge are recorded.
Groups B and C have similar features since most are operated by the
sideways-swing movement of the suction head. In their operation the volume of
turbidity produced as well as the dredging efficiency is governed by the swing
speed and the depth of cut on each swing. This means that increased swing
speed and greater depth of cut will result in more turbidity being generated,
but that the efficiency of removing the sediment (in terms of dredge produc-
tion) will also increase.
54
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TABLE 10. CLASSIFICATION OF DREDGES EQUIPPED WITH SPECIAL DEVICES SUITED TO
DREDGING FOR CONTAMINATED SEDIMENT
Group
A
B
c-i
C-2
C-3
C-4
D
Dredging Technique
Hopper dredge
Cutter suction dredge
Cutterless
suction dredge
Centrifugal
pump type
Pneumatic
pump type
Piston pump
type
Other pump
types*
Grab dredge
Number of
Vessel s
5
1
13
5
3
2
3
* peristaltic and screw pumps
Turbidity is aggravated by cutters, so the cutter suction dredges in group
B generate heavier turbidity than the cutter!ess type dredges in group C. The
Technical Guideline presents data (Tokuji Yagi ^t al.) showing operating
conditions of a cutter suction head in order to maintain turbidity con-
centrations, close to the cutter, of approximately 100 mg/1. The above example
is only one case and is not applicable where dredge types and sediment
characteristics are different. However, it may still illustrate the general
relationship between operating conditions of cutter suction heads and the
suspended solids caused by their operation. The concentration in Table 11 is
the percentage of solids contained in the total discharge passing through the
sump, and the sediment volume in the calculation is that of the jji situ state
prior to the dredging.
TABLE 11. OPERATING CONDITIONS OF SUCTION DREDGES WITH CUTTER HEAD (regulated
SS: 100 mg/1)
Item
Swing speed
Dredged thickness per swing
Concentration of solids in slurry
Operating Condition
9.6 - 11.2 m/min
1.6 m
31 - 36%
Cutterless suction dredges can minimize the occurrence of this type of
turbidity by utilizing various type pumps, by reducing the hydraulic gradient
around the suction head or by fitting special devices to the suction head. As
with cutter suction dredges, the occurrence of turbidity and the dredging
55
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efficiency of cutterless dredges is regulated by the swing speed and the depth
of sediment cut. For example, with clayey sediments, turbidity wil 1 be sharply
increased when the swing speed reaches a certain level.
The Technical Guideline suggests the standard operating conditions as
stated in Table 12 are appropriate for maintenance of the surrounding water
quality within allowable limits.
TABLE 12. STANDARD OPERATING CONDITIONS FOR CUTTERLESS SUCTION DREDGES
Item
Swing speed
Depth of sediment cut
Depth of sediment cut
(final dredging)
Concentration
Operating Condition
for clayey sediments
less than 5m/min
0.3 - 1.0 m (depending on sediments and
water quality)
sometimes less than 0.1 m
less than 30% (average of the total)
"Final dredging" is a process required where all the existing sediments are to
be completely dredged.
Suction dredges (with or without cutters) generally suck a considerable
volume of water with the dredged material. However, some cutterless dredges are
able to exclude water fairly well if specialized methods are employed. Such
dredging methods are not highly efficient and inevitably suck a huge volume of
water in the "finishing-up" stages. The average concentration reported in Table
12 is low for this reason. Under some conditions it may be that more attention
should be given to treating a small amount of in-place sediment after dredging
rather than attempting to remove every last bit of the sediment. Organic
sediments are an example of this situation. Dredging at a high spoils density
by raising the mud content is therefore recommended at the expense of operating
efficiency. This question will be raised again in connection with the
transportation of contaminated sediments.
Table 10 refers to only one cutter dredge since it is the only one equipped
with special devices for contaminated sediment dredging. In contrast to Table
10, Table 11 refers to cutter section dredges without special devices.
GRAB DREDGES
Two of the three grab dredges listed in group D of Table 10 are equipped
with special closed grab buckets designed to prevent leakage of sediments.
These specialized devices are not necessary where turbidity diffusion is
controlled by confinement to narrow channels or by some other method of en-
closure. In these situations conventional dredges have been used. Grab dredges
are most suitable where a higher soil content of the dredged spoils is desired.
56
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VOLUME OF SEDIMENT SUSPENDED BY DREDGE OPERATIONS
Most of the sediment contacted by a dredging head is removed, but some
portion escapes and remains undredged, and some is suspended in the water.
The suspended and diffused sediments are called "suspensoids." Estimating the
volume of suspensoids is difficult. Some observers feel that the volume is
proportional to the total dredged volume. The author and Technical Guideline
support this concept. Table 13 presents a rough estimate for the amount of
sediments suspended per cubic meter of dredged material.
TABLE 13. GENERAL RANGE OF SUSPENDED SOILS
Mode of dredging
Cutter suction dredge
Cutterless suction dredge
Suspended Soils (metric
ton/m3)
5 - 50 x 10-3
0.5 - 5 x 10-3
Suspensoids will be diffused due to tidal currents. Since tidal currents
are complicated it is difficult to evaluate how strongly the resuspended
sediments will affect surrounding water quality.
MEASURES TO PREVENT DIFFUSION OF SUSPENSOIDS
To control diffusion of suspensoids, enclosing booms (silt curtains) are
often employed to encircle the dredge. The many types of materials that have
been rapidly put on the market for this purpose attest to the efficacy of this
technique. Booms are made of non-percolated polypropylene, polyethylene,
foamed styrole and percolated synthetic fibers. To support them, various
types of floats are used. In our Technical Guideline, three typical products
are given for reference among the many products in this line.
TRANSPORTATION TECHNIQUES
TRANSPORTATION VIA PIPELINE
In the case of cutterless suction dredges, pumps suck highly concentrated
sediments and then transport them through pipelines. Some grab dredges also
use pumps and pipelines. The discharge distance is dependent upon the concen-
tration of the dredged spoils. With a higher density, the distance that the
spoils can be pumped becomes shorter (see Table 14).
The discharge distance of a cutterless suction dredge may be increased
considerably by lowering the concentration of solids in the slurry. This is
shown in Table 15.
A booster pump can be employed for long-distance transportation through
pipelines, except when the dredged sediments must be highly concentrated.
57
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TABLE 14. RELATIONSHIP BETWEEN CONCENTRATION AND DISCHARGE LENGTH
Mode of Dredging
Pneumatic pump type
cutterless suction
dredge
Open-type grab
dredge
Concentration
80%
60%
60%
40%
20%
Discharge Length
80 m
240 m
200 m
400 m
500 m
Remarks
Oozer pump used
Dredged by grab
and discharged by
pump
TABLE 15. RANGES OF DISCHARGE LENGTH USING MAIN PUMPS OF CUTTERLESS SUCTION
DREDGES FOR HIGH AND LOW SPOILS CONCENTRATIONS
Type of Pump
Centrifugal
Pneumatic pump
Piston pump
Other special pump
Range of Discharge Length
500 -
80 -
350 -
3,500 m
1 ,500 m
600 m
1,000 m
TRANSPORTATION BY BARGE
When highly concentrated dredged materials are to be transported long
distances, barge transportation will be connected with the discharge pipeline
from a cutterless suction dredge. Two modes of barge systems are described in
the Technical Guideline:
(1) Hopper barge with bottom doors; used only in special cases since there
is leakage from the barge bottom
(2) Hopper barge with a closed bottom; the bottom is closed and a grab or
pump is used for the final discharge of spoils
LAND TRANSPORT
Dredged sediments are unloaded onto a spoils site and then transported to a
designated disposal area. For this purpose the Technical Guide refers to land
transport employing trucks or conveyer belts. Sediments are commonly stocked at
disposal areas and solidified by stabilizers such as lime or cement. Liquid
sediment is rarely transported by trucks. However, the exact degree of
solidification required for land transport has not been decided.
58
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OCEAN DISPOSAL OF DREDGED SPOILS
SPOILS SITES
It is a common practice to confine dredge spoils and convert them to a
non-toxic state. Usually a site on land is necessary, but if the volume to be
disposed is large, nearshore ocean disposal can be better utilized for a
reclamation site. Bulkheads are used to confine dredged sediments which are
sometimes sealed by an overlay of clean soil.
Since coastal areas are already very developed, a minimum space for the
confinement of dredged materials should be determined and secured in advance.
Development of a theoretical calculation for the space required is still in
progress. Empirically derived estimates are now employed.
Some data obtained from actual examples in
in the Technical Guideline as shown in Table 16.
several places are presented
TABLE 16. EXPANSION OF DREDGED SEDIMENTS AND VOLUME OF RECLAIMED LAND
Port
Iwakuni
Ohmuta
Shimonoseki
Tokuyama &
Kudamatsu
Tokuyama &
Kudamatsu
Yokkaichi
Ratio of Volume of Reclaimed Land
to Volume of Dredged Materials
1.35
1.90
2.14
2.28
3.24
3.47
Sediment Expansion Ratio
1.22
1.23
1.51
1.60
1.60
1.28
The sediment expansion ratio refers to the volume of the dredged mater-
ials just after confinement as compared to that of the bottom deposit before
dredging. The wide variance in the above table demonstrates the technical
difficulties involved in theoretically determining fill volumes. The causes
of these difficulties are attributable to the following points:
Sediment volumes are expanding owing to dilution by sea water.
is an extremely variable property of sediment.
This
(2)
It takes a long time for fine particles to precipitate out from
seawater. Since turbid seawater must be accumulated in the reclama-
tion site, a calculation to determine the area required for dumping
is very difficult.
WASTE WATER TREATMENT
The sediments dumped into the fill area replace an equal volume of sea
water. Most suction dredges generally discharge a large volume of water along
59
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with sediments. The sea water is contaminated by contact and must be treated
or released in its contaminated state. The following methods for purifying
sea water are given in the Technical Guideline.
Utilization of Large Land Areas
When a relatively large area of reclaimed land is available, pollutants
can be eliminated through natural sedimentation, after which the purified
water can be released into the open sea. This is the simplest wastewater
treatment. The process may be accelerated by using earth banks within the re-
claimed area to elongate the stream. Agglutinants can also help promote
sedimentation.
Utilizing a Settling Basin
A part of the reclaimed land area is partitioned into a settling basin.
Contaminated sea water leads to the spillway passing through the basin where
pollutants may settle out. Agglutinants may be added at the inlet of the
basin and the deposited pollutants are occasionally removed to maintain depth
in the basin. The index of suspended solids removed by sedimentation using
this basin is shown in Table 17.
TABLE 17. PERCENT SS REMOVED IN THE SEDIMENTATION BASIN
Port
Shimonoseki
Dohkai Bay
SS Density of
In- flow Water
25 - 50 ppm
5,000 - 15,000 ppm
SS Density of
Out-flow Water
13 - 16 ppm
180 - 250 ppm
% SS Removed
48.0 - 68.1%
95.0 - 98.8%
Utilization of a Filter Bed
This method is the most efficient form of wastewater management. A
filter bed is installed at a point higher than sea level. Sea water confined
in the reclaimed land is guided into the filter bed, which can reduce the
suspended solids to less than 15 mg/1.
There are two types of filter—a simple type made of sand, which is
easily replaced when clogged, and another type consisting of a steel tank in
which a filter of sand and anthracite is contained, along with a back washing
device. Table 18 shows results of wastewater treatment using such a filter in
combination with a settling basin.
SOIL STABILIZATION METHOD
Overlay or soil stabilization is necessary for land reclaimed with sedi-
ments because:
(a) The environment can be adversely affected by dispersion of toxic
sediments or release of gas.
60
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TABLE 18. EXAMPLES OF WASTEWATER TREATMENT USING FILTER BEDS
Port
Higashiharima
Yokkaichi
In-flow Water
Qual ity
SS: 150 ppm
SS: 100 ppm
Out-flow Water
Qual ity
SS: 5 ppm
PCB: 0.01 ppm
SS: 10 ppm
Oil: 2 ppm
Flow
Velocity
400 nrVhour
22,000 mVday
Filter
Sand/anthracite
Sand/anthracite
(b) The reclaimed land is strengthened by a soil layer giving it enough
bearing power to be of practical use.
When soil is laid for reason (a) it is called overlaying, while for reason
(b) it is called soil stabilization. They both amount to the same thing.
The Technical Guideline describes the overlay technique as follows:
(1) Direct method
When the surface of the confined material is relatively solid, uncon-
taminated soils can be gradually laid from one side of the reclaimed land by
bulldozers. However, such conditions are quite rare.
An overlay method with selected light materials, scattered by portable belt
conveyers or jet conveyers, is applicable effectively to softsurface
conditions. A cone penetration index of 13.6 - 16.4 kg/cm2 (life: 28 days) was
obtained when a mixture of blast furnace slag with a little cement was used as
the overlay material in thickness up to 60 - 80 cm. A bearing power to permit
heavy vehicle passage can be derived using this method.
(2) Use of sheets
Overlaying can be done by scattering clean solid materials on the soft mud
after setting sheets of nets. Sheets and. nets help distribute the loads imposed
by the overlayment, and control possible swelling of sediments. One example is
given in Table 19.
(3) Stabilization using chemical aids
If lime or cement is spread over the surface material and mixed by earth-
moving machines, the surface will become solidifed. When at a later time good
soils are scattered, a stabilized stratum will be achieved.
In the case where sediments are extremely soft and liquid-like, stabilizers
(mostly lime or cement) are applied and mixed by machines mounted on pontoons.
As a result, liquid sediments can be virtually solidified at an unconfined
compression strength of up to 0.5 - 1.0 mg/cm2- Table 20 gives a classification
value for several types of solidifying agents.
61
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TABLE 19. OVERLAYING TECHNIQUE USING SHEETS AND NETS
Site
Imari
Yokkaichi
Ki takyushu
Sediments
8 m
6 m
7 m
Overpayment
2.0 m
1.5 m
1.5 m
Overlaid
Area
103,000 m2
16,500 m2
52,600 m2
Sheeting
Materials
PP sheet, PP rope to
be anchored on banks
at 20 m intervals
Net (synthetic
resin)
Float (synthetic
resin)
Bamboo rafts at 70
cm intervals, PP
sheet, PP rope
Overlay
Method
Bui Idozer
Dump truck
Submerged
pump
Bui Idozer
Dump truck
Smal 1
suction
dredge
Dump truck
Bulldozer
TABLE 20. CLASSIFICATION OF SOLIDIFYING AIDS
Major Ingredient
Cement
Lime
Agglutinant
Other
Classification of Sol
9
2
2
4 (Asphalt, Soluble
idifying Aids
glass, etc.)
LAND DISPOSAL OF DREDGE SPOILS
In some cases usable reclaimed areas were formed by practicing simple
drainage, natural drying and overlaying. These examples involved a small volume
of less than 10,000 m3 of contaminated mud, dredged in high density by
cutterless suction dredges, and then transported to the fill site. More
complicated methods may be required depending on sediment characteristics.
Sometimes small volumes of sediments, confined and treated, can be used to make
a playground or park.
OCEAN DUMPING
Dredged materials are sometimes discharged into the ocean. The regulations
strictly prohibit discharge of oily or toxic sediments into the sea. But for
organic mud, restrictions are not so severe. Organic sediments will cause some
eutrophication in surrounding waters, but this is alleviated by discharging in
the open ocean. Table 21 outlines one example in which dredging of a bay was
conducted to restore productivity to a fish farm.
62
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TABLE 21. EXAMPLE OF OCEAN DUMPING
Applied sediments
Condition of dumping spot
Specification of barges
Discharge Mechanism
Navigation
Classification
Toxic substances
Oily substances
Water depth
Distance from coast
Distance from dredge
site
Type
Number of vessels
Gross tonnage
Volume of hold
Hold cover
Wave resistance
Type
Pump volume
Discharge depth
Speed (open sea)
Speed (inner harbor)
Trip time
Organic sediments
None
Mineral oil not found
Over 200 m
32 - 35 km
44 - 47 km
Self-propel led
4
490 metric tons each
720 m3
Hatch cover
Wave height 2.5m
Movable discharge pipe
along- side
2,280 mVhour
5 m below the surface
10 knots
4 knots
6 hours
Although ocean dumping is not always economical, it has the advantage that
the natural circulation system will take care of the spoils without subsequent
trouble.
CONCLUSION
Management of contaminated bottom sediments has progressed with adoption
of better environmental standards. There are still many fundamental problems to
be solved. For instance, the problems of what types of contaminated sediments
will be removed, how heavily will suspended solids be produced, and how can the
63
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bearing strength of reclaimed land be improved? Since management techniques for
contaminated sediments will be required for some time, it is desirable that
these fundamental problems be solved as rapidly as possible.
REFERENCE
Tokuija Yagi et al. Influence of operating conditions against dredging capacity
and turbidity. Technical Note of the Port and Harbor Research Institute,
No. 228, September 1975.
64
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DREDGING TOXIC SEDIMENTS IN YOKKAICHI PORT
Hajimi I to
Vice President
Yokkaichi Port Authority
SUMMARY
An outline of Japanese dredging projects to remove contaminated sediments
was presented at the Second Conference held in Tokyo in October, 1976. This
paper is a followup to report on the actual dredging work taking place in
Yokkaichi Port.
INTRODUCTION
Yokkaichi Port is located on the northwest edge of Ise Bay on the Pacific
Coast of Japan (Figure 1). It has played a very important role in the devel-
opment of this region.
In 1952 a petrochemical complex was founded on the outskirts of Yokkaichi
Port; by 1953 fish caught in nearby areas were found to smell bad. The fish
had been contaminated by oil from the bottom sediments and this caused econ-
omic damage to the region's fishing industry.
To clean the port it was necessary to dredge the bottom sediment as well
as to regulate industrial waste water and improve sewage disposal facilities.
The Port Management Organization took charge of the project. Various measures
were taken to prevent secondary pollution before commencing work. These
measures are briefly mentioned in this report.
PLAN FORMULATION
The Basic Law for Environmental Pollution Control was enacted in 1967 and
Pollution Control Programs were formulated in accordance with this law. In
Japan, pollution control measures are comprehensively and systematically ap-
plied in areas where pollution is serious or likely to become serious due to
rapid increases in population or industrial concentration.
In December 1970, the Mie Prefectural Government formed the Yokkaichi
Regional Pollution Control Program and the Yokkaichi Port Authority decided to
carry out the dredging. We organized a Cost Allocation Council in Yokkaichi
Port and the Council set up subcommittees to investigate the following three
subjects:
(1) Standards for dredging bottom sediments in Yokkaichi Port.
65
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TOKYO
NAGOYA
y OSAKA
PACIFIC OCEAN
.'!"•'. .'X .'
:: •• -,—t—'\s
( •
h
^••v^\--./••'
NAGOYA
.- YOKK-vSlCHI
Figure 1. Location.
-------
(2) Methods of dredging and disposing of contaminated sediment.
(3) Basic rules of cost allocation.
Based on the Council's report, the Yokkaichi Port Authority decided to
begin a four-year plan in April, 1974. The contents of the report are out-
1 ined as follows.
Standards for Dredging Bottom Sediments
Any sediment containing more than 4,000 ppm of a n-Hex'ane extraction or
more than 6 ppm of total Mercury is to be dredged. This criterion covers
approximately 2,200,000 m3 out of a total of 2,500,000 m3 of sediment which
accumulated in the area investigated. The ocean bottom to be dredged is
approximately 1,200,000 m2 out of 1,300,000 m2 in the area investigated (Fig-
ure 2).
Methods of Dredging and Disposing of Contaminated Sediment
Since the sediment to be dredged includes a high content of tcxic sub-
stances, we are required to use a dredging method which will not cause second-
ary pollution. Therefore, when selecting dredges it is important to use a
type that will not disperse the sediment and the spoils will contain as high a
concentration of solids as possible.
The method of disposing of the dredged sediment is to construct a re-
taining wall so the dredged sediment can eventually be covered with good soil
and the area reclaimed for use. Approximately 400,000 m2 of the area at the
east end of the Kasumigaura reclamation site was selected where reclamation
work was already being carried out.
Since the distance from the dredging area to the disposal site is nearly
5 km, the transportation method chosen must consider safety and prevention of
noxious odors, as well as economic aspects.
The supernatant water from the dredge spoils is run into a settling pond
constructed beside the reclamation pond where it is treated and discharged
into the sea. The disposed sediment in the reclamation pond will ultimately
be covered with soil.
It is expected that secondary pollution caused by dredging will be pre-
vented by using the above method. To ensure this, water quality and other
environmental indicators will be monitored. In the report it is suggested
that an Investigation and Judgment Committee be organized to direct the mon-
itoring and to judge the results. There is also a supplementary opinion that
some preliminary work should be done before the actual work begins.
Basic Rules of Cost Allocation
Since the basic rules of cost allocation were reported at last year's
Conference, we will not repeat this topic here.
67
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1.000m
Passage
No. 2
Passage
Supernatant Water
Treating Facility
Dredged Sediment
Disposal Site
CO
Dredge
Sediment
Breakwater
Preaepositm
Pond
Kasumigaura Reclamation
Area
Investigated
Dredging Area
Petrochemical
Complex No.8
Private
Piers
Petrochemical
Complex No. 2
Petrochemical
Complex No. 1
National Road No-28
Yokkaichi Station of JNR
Figure 2. Work plan.
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ACTUAL SITUATION
The final plan was decided on the basis of preliminary work done in
March, 1975, in response to the supplementary opinion of the Council (Figure
2). The following explains the dredging method and the actual work situation.
DREDGING
Method
Dredges in use. We employed a dredge with a centrifugal pump, located
under water, and a vacuum type dredge was used for the preliminary work. It
was felt that these two dredge types would not cause secondary pollution.
The principal specifications for each dredge are as follows:
(1) Dredge with centrifugal pump
Dimensions of hull
Length:
Width:
Depth:
Draught:
Dredging depth:
Capacity
Sediment dredging volume:
Maximum pumping distance:
Slurry Solids content:
Main generator:
Dredging pump:
(2) Vacuum type dredge
Dimensions of hull
Length:
Width:
Depth:
Draught:
Dredging depth:
36.0 m
11.0 m
3.2 m
1.8 m
2 - 23 m below the water
level
300 - 700 mVhr
1,500 m
50% (average)
300 KVA x 2 units
110 KW
37.0 m
12.0 m
3.0 m
2.2
17 m
m
Capacity (at 7 kg/cm2 of pumping pressure)
Sediment dredging volume: 210 - 510 m3/hr
Maximum pumping distance: 1,500 m
Slurry solids content: 60 - 80%
Main generator:
Vacuum pump:
450 KVA x 3 units
110 KW
69
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Transportation Facility
(1) Pipe 1ine
The distance from the dredging area to the disposal site was approxi-
mately 5 km and crossed the ship channel. Therefore, we decided to use a pipe
line for transporting the dredged sediment to maintain use of the port facil-
ities. This method prevented noxious odors from escaping along the transpor-
tation route.
To ensure safety, the pipe line was constructed in conformity with the
Petroleum Pipe Line Enterprise Law. The pipe line consisted of 24 inch diam-
eter steel pipes 12 m in length. Pipes on land were 2/5 inch thick and were
connected with flanges. Those on the sea bottom were 1/2 inch thick and
welded together. The regular working pressure in the pipe is 8 kg/cm2 or
less with an emergency pressure of 12 kg/cm2. The velocity of flow in the
pipe is more than 1.2 m/sec.
(2) Safety
To ensure the safety of the pipe line during the dredging work, a central
monitoring system was installed on the station barge which would prevent an
accident by stopping the main pump in case of trouble. The safety facilities
are divided into a safety system and a monitoring system. Their installation
is shown in Figure 3.
(i) Safety system
a. Pressure safety device
This is located on the station barge and, in case the discharge pressure
of the main pump exceeds the regular working pressure of the pipe line, it
will automatically stop the main pump.
b. Emergency shut-off valve
In case of trouble such as a leak, the pipe line can be shut off to
minimize accidents and prevent siphoning of material back out of the pipe and
into the environment.
c. Air removal device
This device keeps the submerged pipe which crosses the ship passage from
floating and prevents any other trouble due to air mixed with the dredged
slurrys.
(ii) Monitoring system
Each pressure gauge and flow meter is connected by wires to the central
monitoring system on the station barge where monitoring is performed at all
times. When the alarm functions, in case of trouble, immediately the super-
70
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Dredger Station Barge
Passage No.1
Passage No. 2
Breakwater
LEGEND;
Pressure gauge
® Flow meter
(0 Pressure safety device
O Air removing device
t£i Emergency shut-off valve
Dredged Sediment Pond
Pre-depositing Pond
Spillway
Supernatant Water Treating Facility
Figure 3. Safety system.
-------
visor can manually stop the main pump on the station barge and instruct the
patrol boat to check for trouble.
a. Pressure gauge
Leakages and other troubles are detected by the absolute and relative
pressure differences at each of six points along the pipe line.
b. Flow meter
Flow meters are provided at each end of the pipe line to find leaks by
checking the differential volume and to keep track of the amount of sediment
transported.
(iii) On-site patrols
It is impossible for instruments to detect problems such as very small
leaks and deformation of the pipes. Therefore, a patrol is performed at all
times and visual inspection is made for early detection of problems.
Station barge. The pipe line is very long and a booster pump is required
to transport the sediment. To shorten the project duration, two dredges were
arranged in parallel, and a sump rehandler type station barge was employed.
The nominal principal items of the station barge are as follows:
Dimensions of hull
Length: 90.3 m
Width: 19.8 m
Depth: 10.6 m
Capacity of hopper: 8,250 m3
Capacity
Pumping volume: 2,500 m3/hr
Total pump head: 66 m
Pumping distance: 6,000 m
Main generator: 2,000 KW
Operations
The dredging site includes the ship passage and anchorage which is sur-
rounded by public wharfs and private piers. A large number of ships come and
go across this area. Since the petrochemical complex is on the outskirts of
the port, the private piers are crowded with many ships loaded with dangerous
cargoes such as naphtha and LPG. It means this area is risky.
We are dredging with the utmost care for the safety of ships navigating
in and out of the port. We often consult about control of navigation with the
persons concerned with shipping companies and with those who have private
piers and keep them informed of the dredging situation. The working period is
normally limited to the hours from sunrise to sunset because we are required
72
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to visually inspect for secondary pollution during the dredging work by look-
ing for dispersion of sediments, floating oil, or leaking of dredge spoils.
Dredging is carried out by two different types of dredges. The vacuum
type dredge is used in the area where the water depth is comparatively deep
and the sediment is thick; the centrifugal pump dredge is used elsewhere.
The plan was to dredge 350 mVhr in the regular sediments (pumping vol-
ume: 1,500 m3/hr at an average sediment content of 23%), 10 dredging hours
per day and 25 working days per month. But in actual practice, the working
efficiency was reduced to approximately 70% because of ships crossing, trans-
fer of dredges and removal of obstacles from the dredge such as vinyl trash,
tires, steel wires, and so forth.
The amount of dredged sediment per day became:
350 mVhr x 10 hr/day x 2 ships x 0.7 = 4,900 mVday
The average amount of dredged sediment per month is approximately 120,000 m3.
DISPOSING OF SUPERNATANT WATER
Method
Dredged sediment pond
The dredged sediment pond is approximately 400,000 m2 and its capacity is
approximately 2.800,000 m3 (Figure 4). A retaining wall separates the pond
from the sea. Steel sheet pilings are driven into the impermeable clay layer
of the ocean floor and 3 mm thick vinyl sheets cover the upper face of the
slope, as shown in cross section in Figure 5.
Treatment facility for supernatant water
(1) Settling pond
The supernatant water from the dredged sediment pond flows by gravity
from the intake pit to the settling pond (Figure 6). Here, the suspended
solids are retained and settle for 24 hours to alleviate the load on the
supernatant water treatment facility and to maintain a constant treatment
capacity.
The area of the settling pond is approximately 14,000 m2 and its capacity
is approximately 52,000 m3. The slope face of the embankment and the bottom
surface are covered with vinyl sheets to prevent water seepage.
(2) Measuring tank
This is used for measuring volume flow of untreated water pumped from the
settling pond to the mixing tank.
73
-------
Dredged Sediment Pond
Pre-depositing Pond
Kasumigaura Reclamation Area
Supernatant Water Treating Facility
Figure 4. Dredged sediment disposal site.
-------
Alignment of Reclamation
t7.82
.5
p*^
^6OfT
3.5
+7.0
s^
8,6
I.I
3 H
•$i--:i:*'^ +3.5 r*~
6.4
^ Vir
^•^*
2.0
ylS
+ 4.0
Figure 5. Revetment cross section of dredged sediment pond.
-------
CM
Dredged Sediment
Pond
Pre-depositing Pond
Mixing Tank
Flocculation Tank
Reclamation Area
-Intake
Figure 6. Supernatant water treating facility.
-------
(3) Mixing tank
In this tank raw water is mixed with coagulants and pH buffers. The pH
buffer is automatically introduced in the proper amount.
(4) Flocculation tank
The chemically treated water from the mixing tank is slowly mixed in this
tank until flocculation occurs.
(5) Clarifier (two tanks: 30.0 m dia x 3.0 height)
The flocculant formed in the flocculation tank is allowed to settle and
separate in the clarifying tanks. Settled material is collected by attached
scrapers and is pumped out and circulated to the dredged sediment pond.
(6) Gravity filters (2 units: 9.45 m dia x 6.08 m height)
The supernatant water is routed to the filter where the remaining floccu-
lant in the water is removed by a filter consisting of anthracite and sand.
After inspection, the treated water is piped out to sea.
Operations
The system for treating and disposing of supernatant water began on
February 3, 1977, with a capacity of 22,000 mVday. The results as of July
31, 1977, showed that the SS in raw water was less than 19 ppm. The disposal
operation is now'being performed without any problems.
MONITORING
Monitoring plan
Following is the outline of the monitoring plan established in accordance
with the report of the Cost Allocation Council, the Interim Guidelines for
Substratum Disposal (the Notification from the Director of the Water Quality
Preservation Bureau of the Environmental Agency, May 30, 1974) and the guid-
ance of the Investigation and Judgment Committe.
Basic monitoring points
We determined a general area where the impact of dredging should be
prevented. Marine phenomena such as currents and tides and utilization of
fishing grounds were taken into account. Four monitoring points were set on
the boundary line of this area (Figure 7).
The parameters monitored at the basic monitoring points are:
(1) Total mercury as representative of toxic substances.
(2) Biological Indices: pH, DO, COD, and n-Hexane extraction.
77
-------
00
Dredged Sediment Disposal Site
LEGEND:
(D Basic inspection point
Boundary line
D Inspection area of fishes
Figure 7. Inspection points.
-------
(3) Light transmission.
The frequency of inspection is usually once a day at ebb tide. The
frequency can be reduced to once a week, except for light transmission, in
those cases where light transmission is correlated with the values of .the
other items. Then, monitoring is properly accomplished even though the fre-
quency of inspection is reduced.
The sampling depths are approximately 0.5 m (surface layer), 2 m (inter-
mediate layer), and 3 m above the bottom (bottom layer). DO is taken at 0.5 m
and 2 m.
Standards are set according to the Environmental Quality Standards Re-
garding Water Pollution according to the Basic Law for Environmental Pollution
Control. They are:
a. Total Mercury: less than 0.0005 ppm
b. pH: from 7.8 to 8.5
c. DO: more than 5 ppm
d. COD: less than 3 ppm
e. n-Hexane extract: less than 1 ppm
The criteria at each basic monitoring point are as follows:
(1) Total Mercury
The number of samples exceeding the standard shall be less than 36.8% of
the total number of samples tested in a week.
(2) pH, DO, COD
The average value in a week shall be less than the standard.
(3) n-Hexane extract
The measured value shall not exceed the standard.
In case inspection shows that a criterion is violated the Investigation
and Judgment Committee will be notified, their opinion heard, and the fol-
lowing measures will be taken.
(1) Total Mercury
Work shall be stopped immediately and necessary measures taken after
investigating the causes.
(2) pH, DO, COD, n-Hexane extract
Inspection shall be increased along with investigation of the cause.
Necessary corrective measures would include slowing down or suspending the
dredging work. These measures shall be taken immediately to bring the project
79
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into compliance with the standard. However, if the cause is not the dredging
work, this response need not be applied.
Auxiliary monitoring points
In order to forecast changes of water quality at the basic monitoring
points and to be able to make quick decisions whether or not dredging should
be continued in case of pollution, auxiliary monitoring points are located
between the basic inspection points and the dredging sites.
Inspection is carried out by measuring light transmission — normally four
times a day. The standard for light transmission is 6 x a where a. is the
baseline value of a taken before dredging is begun, and is temporarily set at
where L = Length of light passage (m)
T = Absolute transmission (%)
Measurements are made at 3 m off the bottom. In case the standard is not
met, the same measures as given in (2) above shall be taken.
Water quality adjacent to the work site
Abnormal turbidity and oil films in the vicinity of the work sites are
looked for at all times. In case abnormal conditions are found, the same
countermeasures as in (2) above shall be taken.
Spillway
The water from the spillway of the sediment disposal site is monitored
for the following substances:
(1) Toxic substances as specified by the Law Concerning Prevention of
Marine Pollution and Maritime Disasters.
(2) pH, SS, n-Hexane extration.
(3) Turbidity, oil content (by carbon tetrachloride extraction and
infrared spectrophotometry).
The frequency of monitoring is once a day for total mercury except when
the mercury content is estimated as a function of turbidity and then the
frequency can be reduced to once a week. Other toxic substances are observed
once a month. SS and n-Hexane extractions are measured once a week. pH,
turbidity, and oil content are continuously measured with an automatic meas-
uring system.
The standards for toxic substances in the spillway were based on the
Standard for Seawater Quality. They are:
80
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a. Total Mercury: less than 0.005 ppm
b. Arsenic: less than 0.5 ppm
c. Cadmium: less than 0.1 ppm
d. Lead: less than 1 ppm
e. Chromium (VI): less than 0.5 ppm
f. Organic Phosphorus: less than 1 ppm
g. Cyanide: less than 1 ppm
h. Alkyl Mercury: not detectable
i. PCB: less than 0.01 ppm
The following were set by the report of the Cost Allocation Council.
a. pH: from 7.8 to 9.0
b. SS: less than 10 ppm
c. n-Hexane extraction: less than 2 ppm
When the results of the inspection procedures do not meet the standards,
the effluent from the spillway shall be stopped immediately and necessary
steps taken until the measured values satisfy the standards.
Noxious odors
Inspections are made so that the residential area shall not be incon-
venienced by any offensive odor emitted from the dredge work. Methyl mer-
captan, methyl sulfide and hydrogen sulfide are all specified by the Offensive
Odor Control Law and are watched for by the project. The standard for these
substances is set at a low enough level that most people cannot detect the
odors in their daily lives. In case an abnormality is detected, necessary
measures shall be taken together with investigation of the cause.
Fish
Mercury content in fish is investigated three times a year in the ocean
area shown in Figure 7. The standard for total mercury is 0.4 ppm average for
each species of fish. If the concentrations in any kind of fish exceeds the
standard, the alkyl mercury content shall be inspected. The standard value
for this is 0.3 ppm. In case the measured value exceeds the standard value,
necessary steps shall be taken together with investigation of the cause.
Monitoring Operations
The results of inspection conducted under the inspection plan from Decem-
ber 13, 1976 (the start of dredging) to July 31, 1977, are as follows:
Basic monitoring points
(1) Total Mercury
The results of measurements for total mercury taken once a day until
March 31, 1977, were all below the detectability limit of 0.0005 ppm. There-
fore, the inspection frequency was reduced to once a week and the results were
all non-detectable. The inspection was carried out by chemical analysis using
81
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the method described in JIS K 0102. This document also describes COD and
n-Hexane extraction methods.
(2) Items relating to the biotic environment
pH and DO were measured once a day and their weekly averages are shown in
the attached table. This shows a tendency for pH to gradually increase from
early summer to mid-summer. DO becomes unstable during the same period. We
thought that these phenomena were related to the occurrence of red tide which
was visually observed. Our baseline of water quality showed that the red tide
often occurred during the same period. The measurements were carried out with
a water quality analyzer.
The average daily values of COD in a week until March 31, and the weekly
values in the succeeding period, are shown in the attached table. Values in
excess of the standard were often observed from early summer to mid-summer.
As mentioned above, we thought this phenomenon was caused by the occurrences
of red tide.
n-Hexane extract was observed once a week and the results were all non-
detectable at a limit of 0.5 ppm.
Auxiliary monitoring points
The maximum increase of orvalues from the baseline, at 3 m above the
bottom at each auxiliary monitoring point, was 3.57. This met the standard.
For reference, the minimum a-value measured in the total period from beginning
the work (once a day until March 31 and once a week in the succeeding period)
was 0.82. The inspection was carried out with a "transmissometer.''
SpilIway
(1) Toxic substances
(i) Total mercury
The results of daily inspections until March 31 were all non-detectable.
The frequency of inspection was therefore reduced to once a week, and results
were still all non-detectable.
(ii) Other toxic substances
The once-a-month results were all non-detectable. The analysis was
carried out according to JIS K 0102, using either gas chromatography or the
thin-layer chromatography (Molybdenum blue) method.
Limits of detectability are as follows:
82
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a. Arsenic: 0.002 ppm
b. Cadmium 0.001 ppm
c. Lead: 0.01 ppm
d. Chromium (VI): 0.05 ppm
e. Organic phosphorus
(parathion, methyl parathion, EPN): 0.1 ppm
(methyl demeton): 0.15 ppm
f. Cyanide: 0.01 ppm
g. Alkyl mercury: 0.0005 ppm
h. PCB: 0.0005 ppm
(2) pH, SS, n-Hexane extract
a. pH
The supernatant water treatment facility is provided with an automatic pH
adjusting system. An industrial pH monitor is used for continuous inspection.
b. SS
The results of weekly inspection gave 7.9 ppm as the maximum value, which
met the standard. The analysis was carried out according to JIS K 0102.
c. n-Hexane extract
The results of weekly inspection were all non-detectable.
(3) Turbidity and oil content
a. Turbidity
The supernatant water treatment facility is designed so the automatic
circulator works in cases of high turbidity. The measurements are carried out
by a turbidity monitor.
b. Oil content
When the oil content is abnormal, an alarm is given. Measurements are
made by an oil content monitor.
2-4 Others
The results of the watch for noxious odors and the inspection of fish
revealed no problems.
FUTURE PROBLEMS
REMOVAL OF UNCONSOLIDATED BOTTOM SEDIMENTS
Sediments with high water content cause problems in the dredging area.
This 30 - 50 cm layer on the bottom is liquid enough to flow aside while
dredging and is therefore difficult to remove completely. Our remaining
83
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problem is to dredge the sediment completely by improving the dredge equipment
and the dredging methods.
SURFACE TREATMENT
The supernatant water from the dredged sediment pond is piped into the
sea after filtration. The problem to solve in the future is how to dehydrate
the remaining sediment which has a high water content, and to cover it with
soil to finish the disposal. In recent years, surface treatment has been done
at many places, but few of these examples disposed of sediment with a high oil
content. Therefore, careful investigation is necessary along with the final
disposal of the spoils.
CONCLUSION
It is important to carefully investigate the area to be dredged. When
this project began we found that vinyl, tires, steel wires, and other trash
would clog the dredge pipe and this unexpectedly lowered the dredging capacity
and prolonged the work.
Sometimes the measured values of the biological indices at the monitoring
points exceed the standards, but not due to reasons caused by dredging. If
this is the case it is not necessary to slow down or halt the work. The prob-
lem is to determine quickly and easily the cause of the high values.
Usual causes are the red tide and organically-rich river water flowing
into the areas. These may be effectively judged by visual means except where
turbidity is high. Then only the surface is visible and a transmissometer may
be used to establish the turbidity, particularly around the dredging site,
after which the dredging effect may be accounted for and the excess attributed
to the other causes.
Color measurements of suspended solids and ignition loss values are two
other possible methods of discriminating among sources of contamination.
At this time, approximately 30% of the sediment has been dredged. Though
we can't yet evaluate the whole project, as of now there have been no problems
with the described methodology.
The standard values at the auxiliary monitoring points were determined
from baseline investigations of the daily fluctuation of the orvalue. This
was based on the concept that any artificial act should not be permitted to
contaminate the natural world. We have maintained this concept since we began
plans for the project, and we will continue to do so until the completion of
the work.
84
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Table. RESULTS OF INSPECTION (December 13, 1976 - July 31, 1977)
\\Period
P
H
ri
(ppmj
C
0
D
(ppm)
Pointx
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
1
2
3
4
1
2
3
4
1
2
3
4
Dec. 13
- 19
8.16
8.19
8.16
8.10
8.10
8.15
7.51
7.54
1.4
1.6
1.3
1.3
Dec. 20
- 26
8.21
8.21
8.26
8.23
8.58
8.59
8.33
8.03
1.4
1.5
1.4
1.5
Dec. 27
-Jan. 2
8.30
8.37
8.37
8.27
7.80
7.90
7.90
8.00
1.5
1.1
1.7
1.9
Jan. 2
- 9
8.23
8.21
8.26
8.23
9.20
9.21
9.20
9.03
1.4
1.4
1.3
1.3
Jan. 10
- 16
8.13
8.18
8.20
8.18
9.28
9.21
8.94
8.95
1.7
1.7
1.7
1.4
Jan. 17
- 23
8.22
8.24
8.20
8.24
8.98
9.03
8.74
8.58
1.6
1.4
1.1
1.2
Jan. 24
- 30
8.22
8.30
8.30
8.31
10.15
10.06
9.58
9.42
1.0
0.9
1.0
1.1
Jan. 31
-Feb. 6
8.23
8.25
8.23
8.24
9.29
9.17
9.16
8.96
1.5
1.3
1.3
1.2
Feb. 7
- 18
8.23
8.26
8.26
8.25
9.26
9.32
8.76
8.97
1.5
1.3
1.2
1.1
Feb. 14
- 20
8.20
8.27
8.26
8.28
9.25
8.81
8.61
8.68
1.3
1.0
1.2
1.0
Feb. 21
- 27
8.20
8.23
8.24
8.24
9.33
9.29
9.03
8.73
1.1
1.1
1.2
1.1
Feb. 28
-Mar. 6
8.37
8.36
8.31
8.28
10.26
9.92
9.52
9.49
1.7
1.7
1.7
1.7
Mar. 7
- 13
8.35
8.41
8.41
8.38
10.69
10.44
10.15
9.64
2.9
1.9
2.2
1.8
Mar. 14
- 20
8.22
8.25
8.25
8.24
8.23
7.91
7.54
7.24
1.4
1.5
1.6
1.6
Mar. 21
- 27
8.23
8.25
8.27
8.28
7.67
7.43
7.53
7.72
1.7
1.4
1.5
1.9
Mar. 28
-Apr. 8
8.24
8.30
8.32
8.31
7.46
7.40
7.31
7.23
1.1
1.1
1.1
1.0
oo
in
\ \Period
Ite\ Point
p
H
D
0
(ppm)
C
0
D
(ppm)
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Basic
Ba s i c
1
2
3
4
1
2
3
4
1
2
3
4
Apr. 4
- 10
8.32
8.88
8.44
8.39
7.88
7.29
7.31
7.15
1.8
1.0
1.6
1.4
Apr. 11
- 17
8.29
8.88
8.29
8.81
6.91
6.51
6.45
6.42
1.7
1.7
1.7
1.7
Apr. 18
- 24
8.13
8.25
8.29
8.28
7.41
7.36
7.01
7.09
1.4
1.5
0.9
1.8
Apr. 25
-May 1
8.25
8.88
8.30
8.32
7.25
7.42
7.28
7.23
1.9
1.7
1.7
1.9
May 2
- 8
8.14
8.18
8.17
8.16
7.54
7.46
7.19
6.88
r 1.7
1.8
1.9
1.5
May 9
- 15
8.46
8.46
8.52
8.54
8.50
8.57
8.59
8.47
1.7
2.5
2.1
2.8
May 16
- 22
8.16
8.18
8.14
8.12
5.99
5.43
5.69
5.09
1.2
1.3
1.2
1.1
May 23
- 29
8.35
8.88
8.84
8.86
6.49
6.37
6.21
6.17
2.1
1.9
2.0
2.3
May 30
-Jun.5
8.27
8.89
8.44
8.42
6.21
6.50
7.08
6.71
3.3
3.4
3.6
3.3
Jun. 6
- 12
8.31
8.88
8.45
8.47
5.76
5.93
6.46
6.66
3.1
2.3
3.1
3.3
Jun. 13
- 19
8.07
8.14
8.18
8.12
4.48
4.24
5.04
8.88
2.6
2.7
2.1
2.3
Jun. 20
- 26
8.16
8.21
8.16
8.15
7.54
7.64
7.84
7.29
2.7
2.7
2.5
2.2
Jun. 27
-Jul.3
8.22
8.28
8.25
8.28
9.19
9.73
8.55
9.13
4.0
4.0
4.0
3.6
Jul. 4
- 10
8.23
8.42
8.42
8.55
8.12
8.88
9.14
10.85
3.3
3.3
3.8
4.1
Jul. 11
- 17
8.24
8.28
8.81
8.31
8.08
8.09
8.19
8.90
4.4
4.4
4.1
4.1
Jul. 18
- 24
8.29
8.86
8.86
8.44
9.36
9.60
9.46
11.04
2.2
2.0
2.4
2.8
Jul. 25
- 31
8.46
8.50
8.44
8.50
11.11
11.36
11.14
11.64
3.7
2.5
3.7
3.7
-------
ACCUMULATION OF METHYL MERCURY IN RED SEA BREAM
(Chrysophrys major) VIA THE FOOD CHAIN
Motoo Fujiki, Ph.D.
Institute of Community Medicine
The University of Tsukuba
M. Fujiki, S. Yamaguchi, R. Hi rota,
S. Tajima, N. Shimojo and K. Sano
SUMMARY
Accumulation of methyl mercury in red sea bream (Chrysophrys major)
results from food chain accumulations—from diatoms to copepoda to the juven-
ile bream.
Diatoms were reared for 24 hours in filtered sea water containing 5.0 ppb
methyl mercury. Methyl mercury taken up by the diatoms reached a concentra-
tion of 3.45 ppm. The diatoms containing methyl mercury were then fed to. the
copepoda for 4 days. The concentration of methyl mercury in the copepoda
reached 3.14 ppm. The copepoda were then fed to the juvenile red sea bream
for 10 days. Methyl mercury concentration in the fish reached 3.10 ppm.
The concentration of methyl mercury in the diatoms and the copepoda was
about 2,000 times as much as that of the culture solution. The increase of
methyl mercury from food to fish was about one. However, the amount of methyl
mercury taken up by the juvenile bream was about 120 times as much as that of
the control.
INTRODUCTION
The mechanism of accumulation of methyl mercury in fish is not yet known.
There are several hypotheses such as: methyl mercury is taken up from sea
water directly through the gills, from the digestive organs via food contain-
ing methyl mercury, or from the gills and/or digestive organs via bottom
sediments which contain methyl mercury.
The author and his coworkers have studied the mechanism of methyl mercury
accumulation in the fish and have learned that accumulation was either di-
rectly through the gills from sea water containing methyl mercury and/or via
food containing methyl mercury. Tarao, Tabata and Yasuhara have studied the
first hypothesis and found no significant direct uptake from suspended solids.
The accumulation in fish via the food chain was not understood because of
the variety of food consumed daily as well as changes in ration over the life
of the fish. To clarify the understanding of the process of methyl mercury
87
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accumulation the author and his coworkers carried out the following experi-
ments on the food chain of diatom (Skeletonema costatum) to copepoda (Acartia
clausi) and copepoda to red sea bream (Chrysophrys major).
EXPERIMENTAL METHOD
The diatom used in this experiment was obtained from the Aitsu Marine
Biological Station of Kumamoto University. It was isolated from other species
and cultured in a solution of 400 grams potassium nitrate, 40 grams dibasic
sodium phosphate, 20 grams sodium silicate, 10 grams ferric chloride, 20 grams
Krewat and 1 ton of filtered sea water. The copepoda used in this experiment
was obtained from a breeding pond in the Ohoyano Branch of the Biological
Station of Kumamoto Prefecture. The red sea bream used in this experiment was
obtained from a fish rearing tank at the Ohoyano Branch Station.
MERCURY ACCUMULATION IN THE DIATOM (Table 1)
1) Experiment A
A culture solution containing 0.5 ppm mercuric chloride and the diatom
were put in a 500 liter fish rearing tank and the culture solution was aerated
by an air-pump for 24 hours. Then the diatoms were collected with a plankton
net and frozen. Methyl mercury in the diatoms was measured by gas-chromatog-
raphy and total mercury by flameless atomic absorption spectrophotometry.
2) Experiment B
A culture solution containing 0.5 ppb methyl mercury and diatoms were put
in a 500 liter fish rearing tank and the culture solution was aerated by an
air-pump for 24 hours. Then the diatoms were collected and frozen. Methyl
mercury and total mercury in the diatoms were measured.
3) Experiments C and D
A culture solution containing 5.0 ppb methyl mercury and diatoms were
added to a 1000 liter fish rearing tank and a 500 liter fish rearing tank and
the culture solutions aerated by an air-pump for 24 hours. The diatoms ob-
tained from the tanks C and D were put together and frozen. Methyl mercury
and total mercury in the diatom were measured.
MERCURY ACCUMULATION IN COPEPODA (Table 2)
1) Experiment E
Filtered sea water containing 0.5 ppb mercuric chloride and copepoda were
added to a 500 liter fish rearing tank and the water aerated by an air-pump
for 24 hours. Then the copepoda were collected and frozen. Methyl mercury
and total mercury were measured.
88
-------
TABLE 1. EXPERIMENTS ON MERCURY INTAKE IN UiATOMS.
i_xpe i i nitMi u > H
Rearing tank 500 1
Mercury concentration MC 0.5 ppb
in Culture solution
ixperimental period 24 hr.
Initial cell number 32 x 106/1
Final cell number 32 x 106/1
Methyl mercury in 0.016 ppm
diatoms
Total mercury in 0.77 ppm
diatoms
Magnification of 1540
total Hg
Magnification of MMC n.a.
B
500 1
MMC 0.5 ppb
24 hr.
26 x 106/1
33 x 106/1
0.93 ppm
1 . 05 ppm
2100
1860
C
1000 1
MMC 5.0 ppb
24 hr.
19 x 106/1
12 x 106/1
D
500 1
MMC 5.0 ppb
24 hr.
79 x 10V1
94 x 105/1
3.45 ppm
4.50
900
690
ppm
900
690
TABLE 2. EXPERIMENTS ON MERCURY INTAKE IN COPEPODA.
experiment > t
tearing tank 500 1
Mercury concentration MC 0.5 ppb
in Sea water
Jait none
Experimental period 24 hr.
Population 400/1
Methyl mercury in 0.038 ppm
copepoda
[Total mercury in 0.28 ppm
copepoda
Magnification of 560
total Hg
Magnification of MMC n.a.
F
500 1
MMC 0.5 ppb
none
24 hr.
1000/1
3.10 ppm
3.50 ppm
7000
6200
G
500 1
0.0
Diatom from
Exp. C
4 days
200/1
3.14 ppm
4.30 ppm
0.96
0.91
J
500 1
MMC 5.0 ppb
none
24 hr.
1000/1
5.0 ppm
5.6 ppm
1120
1000
MMC = methyl mercury chloride
MC = mercuric chloride
89
-------
TABLE 3. EXPERIMENT H. MERCURY INTAKE IN JUVENILE RED SEA BREAM.
numbers
Juvenile red A ..
sea bream deaths
mean length (cm)
copepoda (g) (from experiment J)
Ration
brine shrimp (g)
Methyl mercury in ration (pg)
Temperature (°C)
initial
day
2113
650
9.6
8.7
43.5
—
after
1 day
3092
21
8.2
3.7
22.5
63.5
25.3
after
2 days
3063
29
8.0
3.5
30.0
77.5
24.2
after
3 days
2977
86
8.9
11.5
25.0
107.5
23.0
after
4 days
2735
242
9.5
22.0
10.0
130.0
222.
after
5 days
1693
352
9.8
29.5
147.5
22.9
after
6 days
1648
45
10.1
32.5
162.5
23.4
after
7 days
1494
154
10.4
34.0
170.0
24.8
after
8 days
1386
108
10.9
35.5
177.5
24.9
after
9 days
1363
23
11.8
27.4
137.0
25.5
after
10 days
703
13
11.9
..
—
25.2
-------
2) Experiment F
Filtered sea water containing 0.5 ppb methyl mercury and copepoda were
added to a 500 liter fish rearing tank and the water was aerated by an air-
pump for 24 hours. Then the copepoda were collected and frozen. Methyl
mercury and total mercury were measured.
3) Experiment G
Filtered sea water without any mercury and copepoda was added to a 500
liter fish rearing tank and the sea water was aerated by an air-pump for 4
days. The diatom obtained from experiment C was fed to the copepoda as the
ration for 4 days. The methyl mercury concentration in the diatom was 3.4 ppm
(wet weight basis) and the total mercury concentration was 4.5 ppm. After 4
days, the copepoda were collected and frozen. Methyl mercury and total mer-
cury in the copepoda were measured.
MERCURY ACCUMULATION IN RED SEA BREAM
1) Experiment H (Table 3)
Filtered sea water and juvenile red sea bream were added to a 500 liter
fish rearing tank H and the sea water was aerated by an air-pump for 10 days.
Filtered sea water was continuously supplied to the fish rearing tank and the
water level was maintained by an over-flow system. The copepoda obtained from
experiment J (identical to experiment F) were fed to the young red sea bream
as their ration for 10 days. The methyl mercury concentration in the copepoda
was 5.0 ppm and the total mercury concentration in the copepoda was 5.6 ppm.
Both copepoda and brine shrimp (Artemia sal ina) were used as the ration for
days 1-4 in this experiment because the amount of copepoda containing methyl
mercury was not sufficient to last for 10 days. The brine shrimp were reared
in filtered sea water containing 5.0 ppb methyl mercury (experiment K) and the
methyl mercury and total mercury concentration in them was 2.01 ppm and 2.15
ppm, respectively. At 5 days and 10 days, the bream were collected and fro-
zen. Then methyl mercury and total mercury were measured.
2) Experiment I (Control)
Filtered sea water and the juvenile of red sea bream were added to a 500
liter fish rearing tank. The sea water in the tank was aerated by an air-pump
for 7 days. Filtered sea water was continuously supplied to the tank and the
water level was maintained by an over-flow system. Copepoda and brine shrimp
reared in sea water without addition of methyl mercury were fed to the young
bream as their ration for 7 days, after which fish were collected with a net
and frozen. Then methyl mercury and total mercury were measured.
RESULTS
Mercury accumulation in diatoms is given in Table 1. Table 3 gives the
results of the red sea bream.
91
-------
DISCUSSION
In experiment A with 0.5 ppb mercuric chloride, the total mercury concen-
tration in the diatoms was 1540 times as much as the culture solution. In
experiment B with 0.5 ppb of methyl mercury chloride the methyl mercury
concentration in the diatoms was 1860 times as much as the culture solution.
In experiment C with 5.0 ppb of methyl mercury chloride, the methyl mercury
concentration in the diatoms was 690 times as much as that in the culture
solution. Inorganic mercury was accumulated at a slower rate than methyl
mercury and accumulation at the low mercury concentrations was at a higher
relative rate than in the high level concentration.
In experiment E containing 0.5 ppb of mercuric chloride the total mercury
concentration in the copepoda was 560 times as much as the sea water. In
experiment F containing 0.5 ppb of methyl mercury chloride, the methyl mercury
concentration in the copepoda was 6200 times as much as that in the sea water.
In experiment J containing 5.0 ppb of methyl mercury chloride, the methyl
mercury concentration in the copepoda was 1000 times as much as in the sea
water. In experiment K containing 5.0 ppb of methyl mercury chloride the
methyl mercury concentration in the brine shrimp was 400 times as much as that
in the sea water. In experiment G with a ration of diatoms containing 3.4 ppm
methyl mercury the methyl mercury concentration in the copepoda was 0.91 times
as much as that in the diatoms. The level of intake of inorganic mercury was
markedly low in the diatoms, and the relative rate of intake at low mercury
concentrations was higher than at high concentrations. The methyl mercury
intake of copepoda was higher than that of the brine shrimp. The total amount
of methyl mercury taken up by the copepoda for 4 days was almost the same as
that in the copepoda cultured for 24 hours in sea water containing 5.0 ppb
methyl mercury.
In experiment H (Table 3) involving the diatoms to copepoda to fish food
chain, the methyl mercury concentrations in the young bream after 5 days and
10 days were 0.6 and 0.75 times as much as that in the ration, respectively.
The rate of concentrations is evidently low because the methyl mercury concen-
tration in the infant red sea bream after 10 days was at about the same level
as that of the diatom and the copepoda used as the food. However, the total
quantity of methyl mercury in the bream after 10 days was about 120 times as
much as that of the control. The quantity of methyl mercury fed to the fish
at 5 days and 10 days were 3.53 ug and 7.79 ug per gram of body weight, re-
spectively. The quantity of methyl mercury taken in by the bream after 5 days
and 10 days was 2.34 ug and 3.10 ug per gram, respectively. Since the red sea
bream used in these experiments were in the juvenile stage, growth was quick
and the body weight after 10 days was about 2 times that of the first day.
Therefore, the methyl mercury concentration in the young red sea bream after
10 days may have been unexpectedly low.
Growth of the diatoms was slightly inhibited by the 0.5 ppb of methyl
mercury in sea water. The sensitivity of the plankton to mercury was higher
than that of the fish. Therefore, plankton may be used as indicators of
methyl mercury pollution.
92
-------
TABLE 4. MERCURY (pg/g) ACCUMULATED IN DIATOMS, COPEPODA, BRINE SHRIMP AND JUVENILE RED SEA BREAM (ppm
wet weight basis).
Methyl mercury
Total mercury
juvenile red sea bream
initial
day
0.025
0.029
after
5 days
2.34
2.81
after
10 days
3.10
3.60
copepoda fed to fish brine shrimp fed to fish
control
0.026
0.29
reared in MMC
5.0 ppb 24 hr.
5.00
5.60
control
0.008
0.063
reared in MMC
5.0 ppb 24 hr.
2.01
2.15
control
0.007
0.062
Methyl mercury
Total mercury
copepoda
reared in
MC 0.5
ppb 24 hr.
0.038
0.28
reared in
MMC 0.5
ppb 24 hr.
3.10
3.50
fed diatom
containing
MMC
3.14
4.30
diatom
control
0.008
0.050
reared in
MC 0.5
ppb 24 hr.
0.016
0.77
reared in
MMC 0.5
ppb 24 hr.
0.93
1.05
reared in
MMC 5.0
ppb 24 hr.
3.45
4.50
control
0.004
0.012
UD
CO
-------
CONCLUSION
From these experiments, it was concluded that the most effective pathway
for the accumulation of methyl mercury in the red sea bream is not via the
food chain but from sea water directly through the gills.
94
-------
THE RELATIONSHIP BETWEEN SEDIMENTS AND BENTHOS IN MIKAWA BAY
Tadashi Otsuki
Japan Dredging and Reclamation
Engineering Association
SUMMARY
In this study an attempt has been made to clarify the relationship
between the sediments and the benthos in Mikawa bay. The calculation of the
Sediment Pollution Index (SPI) and its significance are presented. A correla-
tion analysis is made between factors of sediment quality and SPI on one hand
and factors such as predominant benthic species on the other.
The results obtained in this study have indicated that, to a certain
extent, there are correlations between some items of the first group and some
items of the second group, e.g., correlations have been observed between SPI
and species number with a linear regression formula of y = -0.775x + 25.301
(r = -0.765), and between SPI and percent Crustacea with y = -0.903x + 22.292
(r = -0.715).
INTRODUCTION
Pollution in sea water is generally so variable that it can be easily
affected by temporary changes in meteorological and oceanographic conditions.
But pollution in the sediments and in the benthos represents average pollutant
conditions and cumulative tendencies. The benthos can thus serve as an index
to indicate productivity and environmental conditions.
The kind of benthic community found is determined in part by physical and
chemical factors of the sediment and overlying water and the local bathymetry.
Larvae of 70 to 80% of benthic organisms float. These larvae require specific
bottom types on which to settle. Benthos usually feed on suspended organic
matter, organic detritus in the sediment and microalgae. Fish productivity
can be estimated by using the standing crops of benthos in a bay because of
the correlation between fish catch and the volume of benthos.
In order to continue this line of study, investigations into sediment-
benthos relationships were carried out by the author and others at the Mei and
Aichi prefectural fisheries experiment stations. Data on water quality,
sediments, benthos, plankton, juvenile fish and bottom currents were obtained
in Ise and Mikawa bay. This took three years—from May 1969 to March 1972—
but analysis has not yet proceeded far enough to implement pollution control
measures. Therefore this study only attempts to clarify the relationship
between the sediments and the benthos in Mikawa bay.
95
-------
DATA AND ANALYTIC METHODS
Sediment and benthos samples were collected five different times with a
Smith-Mclntyre grab sampler (0.1 m2) at 30 stations in Mikawa bay—May, July,
September, and November in 1969 and March in 1970. The samples have been
sorted into five regions in the bay—the eastern inner part (region A), the
southern central part (region B), the mouth (region C), the northern inner
part (region D) and the northern central part (region E)(Figure 1). A general
description of each region has been derived on the basis of the averages of
the sampling measures, and a few studies have been made regarding the rela-
tionship between sediment quality and benthos in the bay by using these
averages.
RESULTS
AVERAGE SEDIMENT QUALITY
Sediment quality is summarized by region in Table 1 and Figure 2.
Fines content (below 0.074u)
The fines content indicated 13.6 to 89.0% (54.1% average) over all re-
gions. Region C showed 13.6 to 32.5% (22.7% average) which was the lowest
range of values. The highest range of values was in region E which showed
66.0 to 89.0% (81.5% average). All the regions can be ordered approximately
asC
-------
TABLE 1. AVERAGE SEDIMENT QUALITY IN EACH REGION OVER THE SAMPLING PERIOD.
Region
A
B
C
D
E
Item
Time
1969
1970
1969
1970
1969
1970
1969
1970
1969
1970
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
Average
Depth
(m)
6.5
7.2
6.5
8.0
8.0
15.1
21.6
15.1
14.0
16.0
23.1
24.6
23.1
25.0
22.7
8.9
10.0
8.9
12.0
10.0
7.9
7.8
7.9
8.0
8.0
13.3
Fine mud
content (%)
73.6
29.9
52.7
27.0
64.2
74.1
54.2
68.8
50.0
63.6
22.7
32.5
20.5
24.0
13.6
64.1
64.9
65.5
49.0
49.0
76.9
88.8
86.7
89.0
66.0
54.1
Ignition
loss (%)
13.3
7.0
8.3
5.0
14.5
12.3
8.6
8.5
10.7
13.4
6.6
8.7
4.5
5.2
7.3
15.3
8.6
13.6
7.8
9.5
15.5
14.2
14.0
13.2
14.9
10.3
COD
(mg/g)
22.6
17.4
16.9
13.0
-
15.9
12.1
8.9
9.8
9.8
4.4
4.9
4.4
1.9
-
14.0
22.0
9.6
8.9
-
19.4
29.6
14.5
23.8
-
13.2
Sulfide
(mg/g)
0.75
-
0.87
0.26
0.24
0.30
-
0.33
0.27
0.19
0.15
-
0.05
0.10
0.11
0.33
-
0.40
0.40
0.09
0.40
-
0.43
0.46
0.39
0.30
Eh
(mV)
-
-206
-372
-179
-194
-
-174
-303
-164
-323
-
-28
-92
-62
-45
-
-235
-323
-167
-173
-
-351
-363
-318
-373
-222
Humic acid
(P1)
-
0.430
0.595
0.600
0.627
-
0.276
0.232
0.251
0.377
-
0.103
0.231
0.179
0.178
-
0.371
0.309
0.351
0.369
-
0.327
0.398
0.409
0.579
0.360
-------
125° 130° 135° 140° 145° 150°
TOYOHASHI
0 10 km
Figure 1. The five sampling areas (Regions) in Mikawa Bay.
98
-------
Q.
LJ
Q
8
o
Ul
o>
25
20
15
10
5
80
60
40
20
0
25
20
15
1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Fine mud content
Ignition loss
i i i i i i
E
Q 10
O
5
0
-100
-200
•—•*
E -300
•w1
-400
•COD
1 1 I
._>r
1 T I
20 C
15 |
10 z
5 ^
CD
0
1.00 ~
^
o>
0.80 E
I I 1 1 1
0.60
0.40
0.20
0.00
LJ
Q
CO
UJ
-500
1 1 1 1 1
1
1 1
1 1
1969 '70 1969 '70 1969 '70 1969 70 1969 '70
579113 579113 579113 579113 579113
0.80 §
0.60 <=>
0.40 J
o
0.20 "o.
u
0.00 |
A B C D E
Figure 2. Changes of sediment quality in each region.
99
-------
(0.53 mg/g average). The order of the regions was approximately C < B < D
< E < A, and in the A and B regions some trends of gradual decline could be
observed, though not in other regions.
Redox Potential (Eh)
From -373 to -28 mV (-222 mV average) was the range throughout the bay.
The lowest range of -373 to -318 mV (-351 average) was in region E, while
region C has a range of -92 to -28 mV (-57 mV average) which was comparatively
high. The order was approximately E
-------
TABLE 2. BENTHIC COMMUNITY CHARACTERISTICS (average).
Region
A
B
C
D
E
Item
Time
1969
1970
1969
1970
1969
1970
1969
1970
1969
1970
5
7
9
1
3
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
Average
Number of
species
11.4
12.8
1.6
9.2
6.8
11.1
16.1
8.0
17.6
9.3
21.0
25.5
19.6
19.1
25.0
23.0
18.0
16.3
22.3
16.0
6.3
2.5
2.8
7.0
6.8
13.5
Number of
individuals
1625.2
59.6
16.0
92.2
51.0
24.0
60.7
24.4
59.9
16.6
61.1
73.6
49.7
40.5
62.3
89.7
62.7
55.0
49.7
54.0
14.3
2.8
14.3
65.3
38.8
47.4
Biotic index
(NIS)
142.6
4.7
10.0
10.0
7.5
2.2
3.8
3.1
3.4
1.8
2.9
2.9
2.5
2.1
2.5
3.9
3.5
3.4
2.2
3.4
2.3
1.1
5.1
9.3
5.7
9.7
Wet
weight (g)
29.0
2.6
0.1
3.3
1.4
4.2
4.8
1.5
3.8
8.1
3.0
13.1
2.9
3.6
10.6
14.9
30.3
10.7
4.0
9.1
4.6
9.0
4.9
3.1
4.1
6.6
Polychaeta
(%)
16.6
88.7
100.0
87.9
54.3
48.4
68.0
60.9
69.4
53.9
59.7
66.0
56.5
52.5
64.8
71.4
68.7
77.4
66.3
70.8
30.4
27.8
95.7
73.5
63.3
65.7
Mol lusca
(%)
77.5
3.3
0.0
9.9
42.5
32.3
13.1
23.1
13.5
17.4
5.2
14.6
8.3
10.1
7.6
9.2
16.7
10.3
7.1
3.4
34.6
61.1
4.3
17.4
35.2
16.7
Crustacea
(%)
3.0
0.1
0.0
0.2
0.7
6.5
8.4
4.1
6.7
11.8
26.0
13.2
27.2
31.1
20.0
7.7
1.4
0.3
10.2
13.1
2.9
5.5
0.0
7.4
0.0
8.5
Other;
(%)
2.9
7.9
0.0
2.0
2.5
12.8
10.5
11.9
10.4
16.9
9.1
6.2
8.0
6.3
7.6
11.7
13.2
12.0
16.4
12.7
32.1
5.6
0.0
1.7
1.5
9.1
-------
o
ro
40
POLYCHAETA
MOLLUSCA
CRUSTACEA
OTHERS
CO
UJ
Q.
V)
£30
DO
20
.2 10
CD
til
UJ
._WET
WEIGHT
lOOr-
- 0
1969
5 7
1970 1969
357
1970 1969
357
1970 1969
357
1970
3
1969
579
1970
II 3
Figure 3. Changes of benthos in each region.
-------
highest range because of the influence of an abnormal number of Musculus
senhousia in May 1969. The regions can be ordered approximately as E < B < C
< D < A. No seasonal changes were observed in any of the regions.
N-S Ratio (Number of individuals/Number of species)
A range of 1.1 to 142.6 (9.7 average) was observed over the entire area.
Region A, on account of the abnormal numbers of moliusks in May 1969, showed
very high values of 4.7 to 142.6 (35.0 average). The average range was 2.6 to
4.7 in other regions, with region C showing the lowest range of values at 2.1
to 2.9 (2.6 average). The regions can be ordered approximately as C < B < D
< E < A. No trends or seasonal changes were observed in any of the regions.
Wet Weight
Over the entire area the range was 0.1 to 30.3 g (6.6 average). Region
B showed the lowest range of values at 1.5 to 8.1 g (4.5 g average). Region
D showed the highest range at 4.0 to 30.3 g (13.8 g average). In the regions
C, D and E a trend of higher values in July was observed, however, no trends
or seasonal changes were observed in other regions.
Percent Polychaetes
The range was 16.6 to 100.0% (65.9% average) for the entire bay. The
highest range of values was in region D, 66.3 to 77.4% (70.9% average).
Region E showed the lowest range at 27.8 to 95.7% (58.1% average). All the
regions can be ordered approximately asE
-------
Percent Other Species
The range over all regions was 0.0 to 32.1% (9.1% average). The lowest
was observed in region A at 0.0 to 7.9% (3.1% average). Regions B and D had
comparatively high values ranging from 10.4 to 16.9% and 11.7 to 16.4% with
averages of 12.5% and 13.2%, respectively. The order of the regions was
approximately A
-------
TABLE 3. PREDOMINANT BENTHIC SPECIES {1]
Region
A
B
C
D
Priority
ranking
Time
1969
1970
1969
1970
1969
1970
1969
1970
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
5
7
9
11
3
1
Musculus senhousia (M)
Lumbrinereis
brevicirra (P)
Prionospio pinnata (P)
Prionospio pinnata (P)
Theora lata {M}
Goniada sp. (P)
Lumbrinereis
brevicirra (P)
Ophiuroidae (0)
Lumbrinereis
brevicirra (P)
Eumida sanginia (P)
Amphipoda (C)
Paralacidonia paradoxa
japonica (P)
Amphipoda (C)
Amphipoda (C)
Amphipoda (C)
Ophiuroidae (0)
Cirriformia
tentaculata (P)
Lumbrinereis
brevicirra (P)
Lumbrinereis
brevicirra (P)
Lumbrinereis
brevicirra (P)
2
Amphipoda (C)
Paraonis sp. (P)
Lumbrinereis
brevicirra (P)
Lumbrinereis
brevicirra (P)
Prionospio pinnata (P)
Theora lata (M)
Amphipoda (C)
Lumbrinereis
brevicirra (P)
Stauronereis
rudolphi (P)
Amphipoda (C)
Paralacidonia paradoxa
japonica (P)
Amphipoda (C)
Paralacidonia paradoxa
japonica (P)
Paralacidonia paradoxa
japonica (P)
Paralacidonia paradoxa
japonica (P)
Niotha livescens (M)
Theora lata (M)
Cirriformia
tentaculata (P)
Owenia fusiformis (P)
Eunice indica (P)
3
Theora lata (M)
Tharyx sp. (P)
Owenia fusiformis (P)
Lag is bocki
naikaiensis (P)
Raeta pulchella (M)
Lumbrinereis
brevicirra (P)
Goniada sp. (P)
Brachyura (C)
Ophiuroidae (0)
Paralacidonia paradoxa
japonica (P)
Notomastus sp. (P)
Scolplos sp. (P)
Scolplos sp. (P)
Macrura (C)
Spiophanus sp. (P)
Amphipoda (C)
Lumbrinereis
brevicirra (P)
Owenia fusiformis (P)
Cirriformia
tentaculata (P)
Chone sp. (P)
4
Raeta pulchella (M)
Ophiuroidae (0)
Neanthes oxypoda (P)
Neanthes oxypoda (P)
Spiophanus bombyx (P)
Petrasma pusilla (M)
Theora lata (M)
Prionospio pinnata (P)
Goniada sp. (P)
Scolplos sp. (P)
Aricia sp. (P)
Actiniaria (0)
Scolplos sp. (P)
Chone sp. (P)
Nephtys caeca (P)
Flabell igeridae sp. (P)
Flabelligeridae sp. (P)
Actiniaria (0)
Chaetozone sp. (P)
5
Lumbrinereis
brevicirra (P)
Ancistrosyllis
hanaokai (P)
Nephtys caeca (P)
Lag is bocki
naikaiensis (P)
Raeta pulchella (M)
Spiophanus bombyx (P)
Petrasma pusilla (M)
Amphipoda (C)
Lag is bocki
naikaiensis (P)
Goniada sp. (P)
Spiophanus bombyx (P)
Nephtys ciliata (P)
Echiuroidae (0)
Eumida sanginia (P)
Prionospio
krusadensis (P)
Chone sp. (P)
Sternaspis scutata (P)
Echiuroidae (0)
Actiniaria (0)
(continued)
o
01
-------
TABLE 3. (continued)
Region
E
Priority
ranking
Time
1969 5
7
9
11
1970 3
1
Apoda (0)
Prionospio pinnata (P)
Prionospio pinnata (P)
Prionospio pinnata (P)
Prionospio pinnata (P)
2
Goniada sp. (P)
Macoma tokyoensis (M)
Lumbri nereis
brevicirra (P)
Theora lata (M)
Theora lata (M)
3
Raeta pulchella (M)
Lumbri nereis
brevicirra (P)
Nephtys
polybranchia (P)
Brachyura (C)
Ancistrosyll is
hanaokai (P)
4
Theora lata (M)
Terebellides sp. (P)
Cirriformia
tentaculata (P)
Ancistrosyll is
hanaokai (P)
Neanthes oxypoda (P)
5
Anaitides maculata (P)
Scapharca subcrenata (M)
Scapharca subcrenata (M)
Telepsavus costarum (P)
Raeta pulchella (M)
(P): Polychaeta (M): Mollusks (C): Crustacea (0): Others
-------
TABLE 4. PREDOMINANT BENTHIC SPECIES (2) (Polychaeta)
^riority ranking
Region
Time
1
1969
1970
5
7
9
11
3
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Prionospio pinnata
Prionospio pinnata
Prionospio pinnata
Prionospio pinnata
Paraonis sp.
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Neanthes oxypoda
Ancistrosyllis hanaokai
Tharyx sp.
Owenia fusiformis
Lagis bocki naikaiensis
Lagis bocki naikaiensis
1969
1970
5
7
9
11
3
Goniada sp.
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Eumida sanginia
Lumbrinereis brevicirra
Goniada sp.
Glycera sp.
Stauronereis rudolphi
Paralacidonia paradoxa japonica
Spiophanus bombyx
Spiophanus bombyx
Prionospio pinnata
Prionospio pinnata
Goniada sp.
1969
1970
5
7
9
11
3
Paralacidonia paradoxa japonica Notomastus sp.
Paralacidonia paradoxa japonica Scolplos sp.
Paralacidonia paradoxa japonica Scolplos sp.
Paralacidonia paradoxa japonica Scolplos sp.
Paralacidonia paradoxa japonica Spiophanus sp.
Scolplos sp.
Aricia sp.
Nephtys ciliata
Notomastus sp.
Chone sp.
1969
5
7
9
11
3
Nephyts caeca
Cirriformia tentaculata
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Prionospio krusadensis
Lumbrinereis brevicirra
Cirriformia tentaculata
Owenia fusiformis
Eunice indica
Lumbrinereis brevicirra
Flabel1igeridae sp.
Owenia fusiformis
Cirriformia tentaculata
Chone sp.
1969
1970
5
7
9
11
3
Goniada sp.
Prionospio pinnata
Prionospio pinnata
Prionospio pinnata
Prionospio pinnata
Anaitides maculata
Lumbrinereis brevicirra
Lumbrinereis brevicirra
Ancistrocyl1 is hanaokai
Ancistrocyllis hanaokai
Ancistrocyl1 is hanaokai
Terebellides sp.
Nephtys polybranchia
Telepsavus costarum
Neanthes oxypoda
-------
This meant that in region C Paralacidonia paradoxa japonica, Scolplos sp.
and others were predominant, and Lumbrinereis brevicirra, Prionospio pinnata
were scarcely observed. In all the other regions the characteristic feature
was that Lumbrinereis brevicirra and Prionopio pinnata were predominant.
Also, Lagis bocki naikaiensis in region A, Gonaida sp. , Spiophanus bombyx in
region B, Notomastus sp. in region C, Cirriformia tentaculata in region D, and
Ancistrocyllis hanaokai in region E were observed as subdominant species.
In summary, in the polluted inner part of the bay polychaetes such as
Lumbrinereis brevicirra, Prionospio pinnata and molluska such as Theora lata
were usually dominant. In the bay mouth the degree of sediment pollution was
not so great and Crustacea such as Amphipoda were dominant.
THE RELATIONSHIP BETWEEN SEDIMENT QUALITY AND BENTHOS
In accordance with the results of the studies quoted some further studies
were carried out on the relationship between sediment quality and benthos in
Mikawa bay by using the following method.
Results of Correlation Analyses
Cross-correlations were determined between two groups of data. The first
group consists of water depth, sediment quality parameters such as fines
content, ignition loss, COD, sulfide, redox potential (Eh), and P1 for humic
acid. The second group consists of biotic variables such as number of spe-
cies, number of individuals, S-N ratio, wet weight, percentage of genera in
the population (polychaeta, molluska, Crustacea and others), dominant species
of polychaetes and mollusks (Lumbrinereis brevicirra, Paralacidonia paradoxa
japonica, Theora lata, etc).
All correlations with r values higher than 0.600 are shown in Table 5.
Except for ignition loss all the sediment quality factors were correlated to a
certain extent with species numbers and percent Crustacea. In particular,
high correlations were observed between water depth and percent Crustacea
(r = 0.839), and between redox potential and species number (r = 0.844).
Two other high correlations were observed for the physical factors. They
were the one between the humic acid and P1 value and the N-S ratio (r = 0.756),
and between redox potential and number of individuals (r = 0.609).
A few correlations were also observed between the physical factors and
some polychaetes. Between water depth and Paralocidonia paradoxa japonica and
Scolplos sp. , and between redox potential and Paralocidonia paradoxa japonica
the r values were 0.811, 0.757 and 0.753, respectively.
Sediment Pollution Index (SPI)
a. Primary Sediment Pollution Index (PSPI)
We feel that the relationship between sediment quality and the benthos
can be clarified by making use of an index which includes the results of
research and analysis on sediments. This index is called the Primary Sedi-
108
-------
TABLE 5. RESULTS OF CORRELATIVE ANALYSIS (r ^ 0.600).
X
Depth
Depth
Fine mud
content
Fine mud
content
COD
COD
.Sulfide
Sulfide
Eh
Eh
y
Species
Crustacea
Species
Crustacea
Species
Crustacea
Species
Crustacea
Species
Individuals
Correlation
formula
y = 0.742x
+ 3.612
y = 1.189x
- 7.306
y = -0.213x
+ 25.016
y = -0.253X
+ 22.193
y = -0.669x
+ 22.524
y = -0.846x
+ 19.558
y = -23.469X
+ 20.222
y = -36.149X
+ 20.236
y = 0.055x
+ 25.443
y = 0.122x
+ 74.522
Correlation
coefficient
(r)
0.653
0.839
-0.653
-0.621
-0.648
-0.640
-0.600
-0.677
0.844
0.609
X
13.308
13.308
54.071
54.071
13.232
13.232
0.304
0.304
-222.250
-222.250
y
13.487
8.521
13.487
8.521
13.674
8.363
13.095
9.258
13.115
47.455
Standard
deviation
of x
6.373
6.373
22.192
22.192
7.080
7.080
0.182
0.182
110.367
110.367
Standard
deviation
of y
7.246
9.036
7.246
9.036
7.305
9.352
7.125
9.724
7.257
22.076
(conti nued)
-------
TABLE 5. (continued)
X
Eh
Humic acid
(P1)
Humic acid
(P1)
Humic acid
(P1)
Depth
Depth
Fine mud
content
Fine mud
content
COD
COD
y
Crustacea
Species
N-S ratio
Crustacea
Paralacidonia
paradoxa
japonica
Scolplos sp.
Paralacidonia
paradoxa
japonica
Scolplos sp.
Paralacidonia
paradoxa
japonica
Scolplos sp.
Correlation
formula
y = 0.056x
+ 20.555
y = -34.172X
+ 25.403
y = 13.743X
- 0.542
y = -40.601X
+ 22.670
y = 3.292x
- 29.567
y = 1.203x
- 10.883
y = - 0.783x
+ 56.605
y = -0.316x
+ 22.219
y = -2.294x
+ 44.559
y = -0.942x
+ 17.938
Correlation
coefficient
(r)
0.690
-0.690
0.756
-0.662
0.811
0.757
-0.672
-0.693
-0.622
-0.621
X
-222.250
0.360
0.360
0.360
13.308
13.308
54.071
54.071
13.232
13.232
y
ft. 070
13.115
4.400
8.070
14.250
5.125
14.250
5.125
14.211
5.474
Standard
deviation
of x
110.367
0.146
0.146
0.146
6.373
6.373
' 22.192
22.192
7.080
7.080
Standard
deviation
of y
8.982
7.257
2.662
8.982
25.862
10.121
25.862
10.121
26.086
10.748
(continued)
-------
TABLE 5. (continued)
X
Eh
Eh
Humic acid
(P1)
y
Paralacidonia
paradoxa
japonica
Scolplos sp.
Paralacidonia
paradoxa
japonica
Correlation
formula
y = 0.151x
+ 45.722
y = 0.056x
+ 17.007
y = -102.076X
+ 48.956
Correlation
coefficient
(r)
0.753
0.655
-0.682
X
-222.250
-222.250
0.360
y
12.250
4.650
12.250
Standard
deviation
of x
110.367
110.367
0.146
Standard
deviation
of y
21.929
9.372
21.929
-------
ment Pollution Index (PSPI) and is designed to have values from 1-5, where a
high value represents extreme pollution.
Research data in Mikawa bay and other shallow seas or bays, were combined
and for each physical factor of sediment quality an index value was set so
that normal sediments have lower values and more polluted sediments have
higher values. These are shown in Table 6. For the fines content, the PSPI
has a value of 1 to 2 for normal sediments, a value of 3 for eutrophic sedi-
ments, a value of 4 for an excessively enriched sediment and a value of 5 for
polluted sediments. Similar values were assigned for the other sediment
quality parameters, and are given in Table 6.
b. Sediment Pollution Index (SPI)
The purpose of the PSPI was to standardize all the sediment quality
parameters so they varied over the same range. Once this was done the differ-
ent parameters could be combined to define a single index, called the Sediment
Pol 1ution Index, which could then be related to the benthic biota associated
with specific areas of the sea floor.
The SPI is determined in a graphical manner. For example, in May 1969
four parameters of sediment quality were measured: fines, ignition loss, COD,
and sulfide. These are plotted on four- radial axes (see Figure 4). Each axis
is divided into five equal segments to account for the five possible PSPI
values. Essentially, the diagram is in n standardized variables, plotted on
n radial coordinates. The PSPI values at which each measure is deemed to
change from normal to eutrophic, eutrophic to excessively enriched, and
excessively enriched to polluted is determined and a line is drawn connecting
each of the respective points. Thus, the final diagram is a series of nested
polygons. The area of the inner polygon represents the SPI value for a normal
sediment. The area of the second polygon represents the SPI value for a
eutrophic sediment, and similarly for enriched and polluted sediments.
To determine the SPI of a region simply find the particular polygon for
that region as defined by its PSPI values and determine its area. The SPI
value will fall into one of the ranges defined in Table 7 and shown in Figure
4, so that it may be determined as normal, eutrophic, excessively enriched, or
polluted.
In the same way, the results of the sampling program of July, 1969 are
summarized as a series of nested pentagons, since only five variables were
measured. The research in September and November 1969 measured six variables,
thus a hexagonal series was drawn. The 1970 series is represented again by a
pentagon.
c. Changes in SPI
Table 8 and Figure 5 show the changes in SPI obtained for regions A, B,
C, D and E during the period from May 1969 to March 1970. In region C, except
for the research conducted in July 1969, the results showed a normal SPI—
revealing the region to possess clean sediments. Region E was excessively
enriched for the entire period, showing it to be quite polluted. Region A
112
-------
FINE MUD
CONTENT
1969
MAY
IGNITION
LOSS
VALUE P OF
HUMIC ACID
JULY
FINE MUD
CONTENT
IGNITION
LOSS
Eh
COD
SULFIDE
COD
FINE MUD CONTENT
VALUE P OF
HUMIC ACID
SEPTEMBER,
NOVEMBER
SULFIDE
IGNITION
LOSS
COD
FINE MUD CONTENT
VALUE P1 OF
HUMIC ACID
1970
MARCH
IGNITION
LOSS
Eh
SULFIDE
NORMAL
SEDIMENTS
EUTROPHIC
SEDIMENTS
EXCESSIVELY
ENRICHED
SEDIMENTS
POLLUTED
SEDIMENTS
Figure 4. Schematic diagrams of SPI for varying degrees of sediment pollution
and for every sampling period.
113
-------
TABLE 7. SPI FOR VARYING DEGREES OF SEDIMENT POLLUTION AND FOR EVERY SAMPLING
PERIOD.
Year/Month
1969 5
7
9
11
1970 3
Normal
area
< 4.00
< 7.60
< 6.92
< 6.92
< 6.18
Eutrophic
area
4.01
12.00
7.61
18.54
6.93
J
18.18
6.93
J
18.18
6.19
16.16
Excessively
enriched
area
12.01
J
24.00
18.55
J
34.23
18.19
r
34.65
18.19
J
34.64
16.17
30.90
Polluted
area
> 24.01
> 34.24
> 34.65
> 34.65
> 30.91
114
-------
TABLE 8. SPI IN EACH REGION.
Region
A
B
C
D
E
Time
Year Month
1969 5
7
9
11
1 970 3
1969 5
7
9
11
3
1969 5
7
9
11
1970 3
1969 5
7
9
11
1970 3
1969 5
7
9
11
1970 3
SPI
24.000
16.167
23.382
10.392
18.545
14.000
13.314
13.856
9.959
17.594
3.000
7.608
4.763
5.629
6.706
15.000
20.922
18.619
12.557
11.412
21.000
30.432
23.382
27.712
20.922
Average
18.497
13.745
5.341
15.702
24.690
115
-------
B
IGNITION
LOSS
CTi
JULY
VALUE P OF
HUMIC ACID
NOVEMBER
VALUE P' OF
HUMIC ACID
1970
MARCH
NORMAL
SEDIMENTS
EUTROPHIC
SEDIMENTS
EXCESSIVELY
ENRICHED
SEDIMENTS
Figure 5. Changes in SPI for each region by sampling period.
-------
showed an SPI which classified it as excessively enriched in the research
carried out in May and September 1969 and in March 1970 the same region was
classed eutrophic in the research of July and November 1969. The D region,
like the A region, showed values of excessively enriched sediments in May to
September 1969, which decreased to eutrophic values in November 1969 and March
1970. Region B, which showed as excessively enriched in November 1969 and
March 1970, had SPI that represented eutrophic sediments in the research
conducted from July to November 1969.
d. Relationship of SPI and benthos
As discussed in the analysis section, a number of sediment quality param-
eters were found to be significantly correlated with certain of the benthic
biological parameters. The authors feel that individual sediment quality
factors cannot adequately define the habitat and distribution of the benthic
organisms. Therefore the SPI, which is a synthesis of several sediment qual-
ity indices, when correlated with benthic biological parameters, should indi-
cate a closer relationship than individual parameters. Results of these
analyses have indicated the following two significant correlations: Between
SPI and species number: y = -0.775x + 25.301 (r = -0.765, x = 15.245,
y = 13.487, standard deviation of x = 7.150, standard deviation of y = 7.246),
and between SPI and percent Crustacea: y = -0.903x + 22.292 (r = -0.715,
x = 15.245, y = 8.521, standard deviation of x = 7.150, standard deviation of
y = 9.036). These are shown in Figure 6.
For the relationship between SPI and species number approximately 22
species were observed in the normal area. In the eutrophic area were 11 to 21
species, in the excessively enriched area were 7 to 10 species, and in the
polluted area were less than 6 species.
For the correlation between SPI and percent Crustacea the normal area had
19 percent Crustacea, the eutrophic area had from 6 to 18%, the excessively
enriched area had 2 to 5%, and the polluted area had less than 1%.
Correlations between SPI and other measures on the benthos had correla-
tion coefficients less than 0.500. In addition, correlations were run between
SPI and certain dominant species.
Where sediment pollution is advanced, the predominant species found are
often Theora lata (molluska), and Lumbrinereis brevicirra and Prionospio
pinnata (polychaete), but the correlation analyses showed correlation coef-
ficient values of less than 0.250, so no correlations were found between SPI
and these organisms.
But, in the bay mouths where sediment pollution is slight, the dominant
species are often Paralacidonia paradoxa japom'ca and Scolplos sp. Between
SPI and these two species there have been observed negative correlations as
follows: Between SPI and Paralacidonia paradoxa japom'ca: y = -2.500x +
52.357 (r = -0.691, x = 15.245, y = 14.250, standard deviation of x = 7.150,
standard deviation of y = 25.862), and between SPI and Scolplos sp.: y =
-0.971x + 19.923 (r = -0.686, x = 15.245, y = 5.125, standard deviation of x =
7.150, standard deviation of y = 10.121).
117
-------
y =-0.903*+ 22.292
(r=-0.7!5)
y=-0.775x +25.301
(r =-0.765)
0
0
NORMAL
SEDIMENTS
EUTROPHIC
SEDIMENTS
EXCESSIVELY
ENRICHED
SEDIMENTS
[^POLLUTED
LVJSEDIMENTS
Figure 6. Relationship between SPI and number of species, and percentage of
crustacea.
118
-------
CONCLUSIONS AND DISCUSSION
The results have indicated some correlations between physical factors
such as water depth, fines content, COD, sulfide, redox potential, humic acid,
sediment pollution index (SPI) and benthic biotic factors such as species
numbers and predominant species.
It is suggested that the SPI could be an indicator which would show the
degree of sediment pollution, and in accordance with this concept the authors
hope that SPI could be applied as a standard criterion for making decisions on
removal of organically polluted sediments from the sea bottom.
These conclusions may not apply to other inner bays or shallow seas, but
future studies should be made in these and other areas and also include new
factors such as sea water and plankton measurements. More research and anal-
ysis in different areas will add to the stock of data and lead to development
of guidelines for conservation and improvement of the marine environment.
REFERENCES (all in Japanese)
1. Mie and Aichi Prefectural Fisheries Experimental Stations: Reports on
the quality of water and sediment investigated in Ise and Mikawa bay, p.
1-599 (1972).
2. R. Kitamori: Sediments and Benthos, Ocean Age, No. 12 p. 16-19 (1971).
3. R. Kitamori: Sediment pollution and marine biota, Journal of Environmen-
tal Pollution Control, Vol. 11, No. 5 p. 22-29 (1975).
4. G. Yamamoto: Marine Ecology, p. 1-213, Tokyo Univ. Shuppankai (1976).
5. T. Otsuki: Studies on the humic acid in the shallow sea sediments,
(Doctoral Thesis Tokyo Univ.) p. 1-378 (1974).
119
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A HYDRODYNAMIC STUDY OF LAKE POLLUTION
T. Yoshida
Japan Bottom Sediment Association
SUMMARY
The serious problem of lake pollution confronts Japan as well as other
countries. It is over ten years since Lake Suwa first experienced heavy algal
blooms and now other lakes such as Biwako, Kasumigaura, Yunoko, and Nakaumi are
also in urgent need of reclamation.
Since most lakes are primarily polluted by organic wastes of domestic or
industrial origin, the pollution problems of lakes have been investigated in
terms of the chemical and ecological effects of these pollutants. These effects
are determined in part by the hydrodynamic functions of lakes so a hydrostatic
study alone would be of little significance. The purpose of this paper is to
describe and explain the hydrodynamic function of lakes, and then to pursue the
relationship to organic pollution.
A MATHEMATICAL MODEL OF A LAKE
Lakes and marshes are natural reservoirs. Runoff water from the mountains
flows into them, and after an interval of residence time it flows out via
connecting rivers. Meanwhile, the quantity of water in the lake is equilibrated
by means of rainfall, evaporation from the surface and other inputs and losses
(see figure below).
Inflow
Rainfall,
»-
1 '
i
i
i
Evaporation
Lake
Runoff _
Pollutants
Irrigation
In the past the only solids added to the lake were natural sediments
transported by rivers. But with the advance of civilization, materials from
factories and domestic sources began to cause pollution.
121
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In studying the behavior of solid pollutants in lake water, conservation
and non-conservative properties must be accounted for. Let decomposition from
oxidation be the only non-conservative property, then we get an equation for the
motion of solid particles in lake water as follows:
at ax az xax2 zaz2
where:
c = concentration of suspended solids
v = flow velocity of lake surface flow layer
u = mean fall velocity of suspended solids (ss)
k = velocity factor for decomposition by biological oxidation
K = diffusion coefficient in the horizontal direction
K = diffusion coefficient in the vertical direction
The coordinates are shown in Figure 1. The term for the y-axis is ne-
glected in Equation (1) for ease of calculation.
Since it is very difficult to get an exact solution to Equation (1), the
last term is neglected and the following equation is solved:
at ax az x ax2 z az2
As the solution of Equation (2), the following separate function is taken:
c = T(t)S(x,z) (3)
From Equation (2) and (3) we get:
s_vas_uas
11= xMx2 zaz2 3x az (4)
T
Then by putting both sides of Equation (4) equal to -n2, the following equations
are obtained:
122
-------
T1 + n2T = 0 (5)
x ax2 z az2 ax az
From Equation (5):
T = Cie"n2t (7)
is derived.
In order to solve Equation (6) we transform the coordinates as follows:
-f v y + " .
V oi/ A oi/ *- j
- S(x,z)e x z
u2/Kz
2 ' K
x
"2/Kz . z
The transformation reduces to the following equation, although the calculation
is omitted here.
= 0
V2/K + uVKz
/\
By putting
m = 1 — (10)
v2/K + u2/Kz
s\
Equation (9) is rewritten in the following form
- m* = 0 (11)
a|2 at2
123
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The factor m in Equation (11) denotes the turbulence of lake flow and
varies between 0^1. In the case of steady flow m = 1 and n = 0. The smaller
the value of m, the greater the turbulence becomes.
We know the values of m for lakes which are subject to a changing annual
load of pollutant input. The following example indicates that the value of m is
nearly equal to 1 . By putting the following data: v = 100 m/h, u = 0.018 m/h,
K = 72 m2/h, K =0.36 ir,2/h and n = 0.01 h"1 into Equation (10), we get
m - 1
m - I -
v2/K + u2/Kz
/\
4 x °-
1002/72 + 0.0182/0.36
= 0.999992
Consequently we may regard any lake flow as a steady one. Then Equation (11)
becomes (for a lake flow):
-*=0
(12)
The general solution of Equation (12) is
* =
+ BsinAO-fccosh \/\2 + l.f, + DsinhlA2 + l.| i (13)
where arbitary constants A, B, C and D are determined by four boundary condi-
tions. The boundary conditions are set as follows:
1 /-"I
i) x = 0; c = TT-J c(o,z)dz
i
11) x= L; = 0
iii) z = 0; uc - Kz = 0
=£; + a*= 0
= 0; - b* = 0
(14)
1V) Z=H1; ff =0
124
-------
where a, b, h and £ are all non-dimensional symbols represented by the following
equations:
K
a =
x \/ v2/K + u2/K
X Z
K
2 \/v2/K + u2/K.
X, V2/K + u2/K
A £
K
(15)
- L\/v2/Kx +
?V K
u2/K
The solution of Equation (12) can be obtained by determining the eigenvalue
An, and eigenfunction *n, although the mathematical operation is not described
here in detail. The eigenvalues An are obtained as roots of the following
equation.
2b A
tan A
(16)
4c_
Finally, the concentration of suspended solids in lake water is represented as
follows:
(17)
e" 1bhjx2n(xncosxn; + b sin \ni,)\\/\2n + 1 cosh\/X2n + 1 (n c) + a sinhN/ \2n + 1 (n 5)
sin xnh,(x2n + b2)-j_ (X2n + b2)h! + 2b} ^A^n + 1 coshVx2n + 1 + a sinh Vx^n + 1
o
/m
*C
Figure 1. Mathematical model of lake
125
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The mean concentration of the supernatant flow layer (Figure 1) is calcu-
lated as follows:
bx2n - 4a
2a
)}
° n(x2n + 1 a2)(x2n + b2) {(x2n
n = 1
j + 2b}
a)
(18)
By putting
n 1
Equation (20) becomes
r . a£ -/X2n + 1 i »
bX2n 1- 4aVX2n = 1e + 2a V X2n + 1 + (x2n + 1 + a2})
£ (X2n + 1 a2){(x2n + b2) (X2n + b2)^ + 2b}(V/x2n~TT+ a)
cm = C (jim
(19)
(20)
Next, the mean concentration of suspended solids (Figure 1) at the bottom
border line of the surface layer is represented as
c(c = M 2cr
at -vA2n + 1 a
X2n I- 4avx2n + 1 e + 2avx2n + 1 + (x2n + 1 + a2) j
- a2)f(X2n
l
(21)
a)
Similarly, by putting
n = 1
r t ai -/X2n + 1 i
hi X2n |- 4av^2n + 1 e + 2aVX2n + 1 + (X2n + 1 + a2)} (22}
£(X2n + 1 - a2){(x2n + b2) hj + 2bj (\/X2n + 1 + a)
we get
c = coc = — denotes the mean concentration of SS in the entire lake.
o
The mean concentration of runoff may be calculated as follows:
126
-------
c. = 7—; c dc
A h/Q a t
/ o - yX2 (24)
= 8c
b2){(A2n)h1 + 2b}(Vx2n + 1 + a)
Similarly, putting
00
,„ _^~ " ' " (25)
<|)a = w ^ v - .
(A2n + b2)|(A2n + b2)ht + 2b) (V\2n + 1 + a)
gives the following equation
(26)
Finally the equation of concentration at the bottom layer becomes
«n=«
because v = Kx = Kz = 0 at the bottom. Therefore, the concentration at the lake
bottom is
SOLIDS IN LAKE WATER
The solids contained in lake water are divided into two parts, that portion
which remains on a No. 5C filter and the other which passes through it. The
former is defined as suspended solids (SS), and the latter, dissolved matter.
This method is prescribed by JIS KOI 050. The sum of these is called evaporation
residue, because it is the quantity which remains after evaporation.
127
-------
ppm
250
200
150
100
50
DISSOLVED! MATTER
1966 MEASURED
SUWAKO
Figure 2. Dissolved matter and SS of Suwako.
The evaporation residue is an unexpectedly large quantity in lakes. Figure
3 shows the results of measurements made in Lake Suwa. Quantities of residue
differ according to season. It is thought that the large amount in the summer is
due to plankton and the small amount in spring is due to run-off during floods.
As Figure 3 shows, the amount of SS acounts for a small percentage of the
residue. Therefore, it would appear that a study of the behavior of suspended
particles in lakes would not be of significance.
128
-------
, (2.0m)
k(2.2m)
Figure 3. Sampling Sites in Suwako Lake (SS as fraction of
total evaporation residue).
2mm
1.2M
SS
dissolved
matter
mostly remain
inside lake
mostly flow
out of lake
However, most of the dissolved matter flows out of the lake, and the major
portion of the SS remains inside the lake. Because of this effect the pollution
of the lake is dominated by SS. Lake water after filtration with filter cloth,
glass filter and micropore-filter becomes transparent. That is, the dissolved
matter, which makes up the largest fraction of an evaporation residue, has no
influence on the transparency of lake water. Furthermore, organic matter
accounts for 70% of the total SS, but the non-organic fraction predominates as
dissolved matter. From this it is clear that the properties and behavior of SS
have a strong influence on lake pollution.
As mentioned before, evaporation residues increase in the summer. The
amount of SS therefore also enlarges. This may be due to plankton blooms.
the measurements
in summer (July)
were performed, a diatom,
the green waterweed Micro
In winter and spring, when
Asterionella, was dominant, and
actinium was generated in large quantities, followed by Synedra, Microcystis,
and finally algal blooms of a blue-green color. These facts indicate that
chemical and ecological studies should also be considered in addition to an
understanding of the physical behavior of suspended solids in lakes.
129
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SETTLING RATE OF POLLUTANT PARTICLES
In the calculation of the hydrodynamic lake equations it is difficult to
evaluate the settling rate of pollutant particles. Empirical measurements of
settling in the lake were conducted as follows.
From August to December, 1966, the quantity of settling matterial was
measured by the apparatus shown in Figure 4.
Figure 4. Measuring apparatus.
130
-------
The measurements were performed for 42 days and at 6 sites in the lake as
shown in the map of Figure 3. The mean value of each point is given in Figure 5.
0
FALL QUANTITY g/mVl
5 10 15 20
25
MEASURING POINT
CD ui -P> OJ ro -*p
i i
1 1 1
17.0
16.1
;;;:;;|:;:;:i:;:i:;:;:;:;:;:;:;:;;;:S:;:;g:;;;;;:j
l;|i;:S;i;Si;ijl0.2
13.1
| 13.5
15.0
i - i
1 1 1
Figure 5. Settling rates.
On windy days the sediment was stirred up and the quantity of material
settling was increased. The average wind velocity was 3 m/sec over 42 days.
It is possible to estimate the settling velocity of pollutant particles
from the above data. If c denotes the mean concentration of SS in lake water,
and u, the settling rate of solid particles, the falling material per unit area
and unit time becomes
uc = 15.6 g/m2/day =
_6
+ 0.26 x 10 6 m3/m2/h
where the unijt weight of a particle is taken as 2.5 g/cm3. For the concentration
c = 14.5 x 10 6, we get
131
-------
-* r\
x IU" = 0.018 m/h = 0.0005 cm/sec
14.5 x 10 6
This value corresponds to a mean particle diameter of 3.5u as derived from
Stoke1s equation.
From the foregoing theoretical equations it is found that the value of u
should be in the range 0.0003 -^ 0.0005 cm/sec. Thus, the mathematical estima-
tion is in good agreement with the experimental measurements made in Lake
Suwako.
THE ABILITY OF A LAKE TO DILUTE POLLUTANTS
Estimation of the input values K K , H, and v, etc. by mathematical
methods, can save much labor and money. One such method uses the conditional
equation of the mass balance of pollutant solids as follows:
BHXL
cQ(l + at)(l - <{>A)Q = —— cm + u c(hx)A (29)
where
t = residence time for surface flow in the lake
a = surface area of lake
Q = quantity of water flowing into lake
Equation (29) is arranged in the following form
TJ * = ' - »A - *m (30)
This is used to check whether the inputs are proper or not in the calcu-
lations of <|>c, (|>A and <{>m. Since it is generally allowed to set <|>c -f m, Equation
(30) may be rewritten as follows.
<|>c = , . uA (31)
1 Q
132
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The factor <(> relates to the dilution ability of the lake, since it is
the ratio of the mean concentration of lake water to that of the inflow. The
smaller the value of <|> , the larger the dilution ability of the lake. Equation
(31) shows that the larger the lake area and the smaller the quantity of
uA
the ratio ~- is
influx, the smaller the value of becomes. Consequently,
an important index for the estimation of dilution ability. This relationship
is examined for the three lakes, Teganuma, Suwako and Kasumigaseki.
TEGANUMA
0.8
0.7
0.6
0.5
0.4
0.3
0.2
O.I
I
I
0 100
120 140
-* V m/h
160
Figure 6. Determination of
Before discussing the dilution abilities of the three lakes, the method
for using the conditional Equation (30) is shown for Lake Teganuma. In Figure
6 the values of <}> and <|>fl corresponding to two points v = 100 m/h, and v = 143
c 1 - uA
m/h, are plotted and the line of the conditions equation (j> = is drawn.
c 1 + uA
133
-------
The point where the lines intersect, (v = 125 m/h) gives the answer. In
this case the velocity v becomes a major variable, because the values of u, K
and K are restricted to small ranges.
TABLE 1. DILUTION ABILITIES OF THREE LAKES
Lake Area, A (m2)
Inflow Q (m3)
^, u = 0.018 (m/h)
Lake length, L (m)
Surface layer
thickness, H (m)
*A
*c
Teganuma
118,000
6,790
0.31
7,000
0.78
0.27
0.55
Suwako Kasumigaseki
13,300,000 171,000,000
46,800 1,140,000
A 5.11 9 ,
A1 3.31
4,000 300,000
0.5 1.0
0.013 0.022
0.229 0.258
uA
When we calculate the value of ^ we need to take the effective lake area
A1 through which the inflowing water passes directly.
(a)
A = A
A1 < A
134
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In the case of (a) in the drawing A is equal to A1, but in the case of (b)
A' should be estimated to be much less than A because of the effect of back
currents and eddies. Among the three lakes, Lake Suwako corresponds to the case
of (b). The dilution ability of Teganuma is worst with a value of c = 0.55. In
the other two lakes the concentration of inflowing pollutants is diluted to
about one fourth on the average.
CONCENTRATION OF SS AND COD IN LAKE WATER
Among the many indices for representing pollution of lake water, chemical
oxygen demand (COD) is a typical one. Figure 7 shows the growth of COD values in
3 lakes, Teganuma, Suwako and Kasumigaseki in which pollution has increased in
the last 10 years.
ppm
24
20
01
Ld
Q
8
12
8
0
TEGAMURA
SUWA-KO
KASUMIGA-URA
I
1950
I960
1970
I960
Figure 7. Plot of COD against time in three lakes.
135
-------
RIVER
•" • ' '/SHINANO
PACIFIC OCEAN
Figure 8. Location of the three lakes.
136
-------
When the lakes were not polluted as shown in Figure 7, the value of COD
amounted to only 2 ppm. But after pollution began, COD increased to 20 ppm in
Teganuma, and 7 ppm in Suwako and Kasumigaura.
The relationships between the SS concentration and the COD of lake water
are shown in Table 2.
TABLE 2. CONCENTRATION OF SS AND COD OF THREE LAKES
Teganuma
SS (ppm)
COD (ppm)
BOD (ppm)
COD/SS
55.1
(mean of 15
values)
16.8
( " )
12.6
( " )
0.30
Suwako
(1966)
14.5
(mean of 42
values)
4.95
(mean of 63
values)
5.27
( " )
0.34
Kasumigaura
(1974)
8.67
(mean of 12
val ues)
6.8
( " )
2.55
( " )
0.78
As long as COD (or BOD) represents the organic fraction of suspended solids
it appears that there should be some relationship between them. As an approach
to this idea the ratio COD/SS is considered. This ratio is nearly equal in Lakes
Taganuma and Suwako, but is much higher in Lake Kasumigaura.
Among nutrients, phosphorus is regarded as one of the most important
elements for maintaining an ecological and chemical cycle. Table 3 gives the
values of total phosphorus concentrations for the three lakes.
137
-------
TABLE 3. T-P OF THREE LAKES
Teganuma
T-P (mg/1) 0.91
SS (mg/1) 55.1
TP/SS 0.016
Suwako
0.05
14.5
0.022
Kasumigaura
0.05
8.67
0.052
COD/SS
1.2
1.0
0.8
0.6
0.4
0,2
I
0.02
0.04
T-P/SS
0.06
Figure 9. Relationship between COD/SS and T-P/SS.
Figure 9 shows the close relationship between the ratios COD/SS and T-P/SS
although the amount of data are insufficient to make a general rule. We can say
however, that the large value of COD/SS in Kasumigaura may be related to the
high value of T-P/SS. The extraordinarily high values of SS and COD in Teganuma
results from the small dilution ability of the lake.
138
-------
QUANTITIES OF POLLUTANTS DEPOSITED AND COD OF SEDIMENT
The mean concentration of suspended solids at the lake bottom is given as
CB = cChj) = CQ
-------
If they differ it may be due to:
1) incomplete sampling
2) anaerobic decomposition
3) other
In any case the difference is represented by the ratio
COD, (measured)
T = COD$ (calculated)
Now the numerical example of Lake Teganuma is cited.
(36)
0
1965
1970
1975
Figure 10. Growth rate of COD of water in Lake Teganuma.
140
-------
As the figure shows, the value of COD was 3.6 ppm in 1966. After 8 years it
increased to 18.5 ppm. Thus,
1 + at = ^4 = 5.139 and therefore
6. b
a = 5.139-1 _ 4.139 _ , .. ,«-5 .^
8 x 8760
= 6 x 10 5 h
So the concentration of influx in the beginning year 1966 becomes
3.6 3.6
00 U)
073 = 12 Ppm
fic = c (be u(t + -
S oo T 2
= 12 x 10~6 x 0.55 x 0.018 (7.080 + | x 6 x 10"5 x 70,0802)
= 0.0258 mVm2
Ws
CODC = (1 + e ) -rr w
o 0 Mo
xO.3
= 0.0775 = 77.5 mg/g
CODs(measured) = 44.6 mg/g (average of 24 values, May, 1975)
The difference between the calculated and measured values is large. In this
case, sediment samples were taken from depths less than 0.5 m. This suggests
that 0.5 m is not deep enough to sample the entire accumulation of pollutant
solids. If we calculate the deposit quantity with H2 = 0.9 m, we get the value
CODS = 43.0 mg/g, which is nearly equal to the measured one. This indicates that
the sampling should have been conducted to a depth of 0.9 m.
Table 4 shows the results of similar calculations for the other pollution
indices using the above correction.
141
-------
TABLE 4. RATIOS OF t FOR OTHER POLLUTION MEASURES
Water
BOD
T-N
T-P
0.2/SS
0.1/SS
0.016/SS
Sediment
(calculated)
mg/g
28.7
14.3
2.29
Sediment
(measured)
mg/g
7.9 0.27
4.75 0.33
1.99 0.87
From this table it is conjectured that the phosphorus compounds in the
sediment underwent some anaerobic decomposition. For BOD and Total Nitrogen the
circumstances are quite different. Presumably most of the organic materials
associated with BOD and T-N were decomposed after deposition at the lake bottom.
DISTRIBUTION OF CONTAMINANTS IN LAKES
In the previous sections the paper describes only the organic pollution of
lakes. But some lakes are also contaminated by toxic heavy metals. Lake
Teganuma is a good example of this situation. Here the distribution of
contaminant deposits in the lake is accounted for by using the previously dis-
cussed theoretical equation
CC.
LJ
O
o
o
0
(C = hi) = cf
(B = concentration of
pollutants at
lake bottom)
In order to calculate the quantities of contaminants deposited, it is
necessary to know the concentration of SS at the lake bottom. This is derived
from Equation (37) as follows:
09
c(C =
= 2c
(a -
o X i (A*n + b2)
n = 1
+ 2b
(37)
142
-------
Since the quantities of solids deposited per unit area and unit time are uc(hj),
the contaminants contained in them should be distributed according to the
function:
fa -
The Teganuma marsh is cited as an example, where the measurement of heavy
metals in sediment was conducted at the 6 sites shown in Figure 11.
TONE RIVER
, -TEGANUMA
4 5
Figure 11. Sampling sites in Teganuma marsh.
The heavy metals measured were: Cd, Zn, Cu, Pb, Cr, Ni, Mn, Fe. The
samples were taken from the surface to a depth 50 cm of sediment and divided into
5 equal layers. The concentrations of Zn and Cu at the six sites are given in
Table 5.
TABLE 5. DISTRIBUTIONS OF Zn AND Cu IN TEGANUMA MARSH
(ppm and %)
No. 1
Zn 378(100)
Cu 147(100)
No. 2
61.7(16.3)
27.0(18.4)
No. 3
56.4(14.9)
35.7(24.2)
No. 4
43.3(11.5)
23.5(16.0)
No. 5
54.1(14.3)
37.2(25.3)
No. 6
53.0(14.0)
36.5(24.8)
143
-------
The figures of Table 5 are plotted in Figure 12.
100
Ol
1000 3000
Distance from inflow
5000m
Figure 12. Distributions of Zn and Cu in Teganuma Marsh.
Figure 12 shows that the distribution curves of both metals strongly
decline because of their heavy specific weights. These curves appear quite
reasonable and within theoretical expectations except for the small deviations
at site No. 5 which result from the neck at the lake center.
It is worthwhile to note that the theoretical curves obtained by the
following inputs:
and
Cu u = 0.11 m/h
Zn u = 0.14 m/h,
(common v = 125 in/hi, Kx = 72 m2/h,
Kz = 0.36 m2/h, L = 7000 m)
144
-------
are in good agreement with the measured ones. This is evidence that most of the
Zn and Cu was transported to the lake by inflowing rivers.
The same relationships are noted for Fe and Mn and for Zn and Cu (Figure
13), with a slight difference.
100
o>
1-5
Q-o
20
0
I
I
2000
6000m
Figure 13. Distributions of Fe and Mn.
There is no great change in concentrations along the length of the lake.
Therefore, these flat curves do not represent the precipitation of metals, but
may perhaps be deviations from the normal characteristics of native sediment
soils.
CONCLUSION
To understand pollution of lakes by solid materials it was necessary to
understand the hydrodynamic behavior of the solid pollutants. To acheive this
end theoretical equations were deduced. The first result derived from these
equations was the concept of the dilution ability of a lake. This was illus-
trated with examples of three lakes. Next, the theoretical estimation of the
deposited quantities of solid pollutants was described, and the relationships
between the accumulated quantities of pollutants and common pollution indices
for sediment was discussed. Finally, the hydrodynamic equations were applied to
the distribution of toxic heavy metals in lake sediments. From the above
results it may be concluded that hydrodynamic analysis of lake pollution is a
useful tool.
145
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THE TOXIC SUBSTANCES CONTROL ACT (TSCA):
HOW IT AFFECTS EPA FROM A RESEARCH
AND ENFORCEMENT STANDPOINT
Eugene I. Wall en
Deputy Director
Office of Toxic Substances
U. S. Environmental Protection Agency
Washington, D.C. 20460
INTRODUCTION
The Office of Toxic Substances is relatively new and Mr. Steven Jellinek
was only recently confirmed as an Assistant Administrator of EPA to head the
Office. The purpose of the Office is to administer a law, the Toxic Substances
Control Act, which was passed in October of 1976 and became effective January
1, 1977.
The purpose of the law is primarily to gather health effects data and to
make these data available to everyone—to citizens of the United States, to
other countries, to any labor union member or to anyone who wishes to have
the information. A second purpose of the Act is to gather new health effects
information through the testing of toxic chemicals. Really, the name, "Toxic
Chemicals" is not quite correct. The law should be titled "The Regulation of
Industrial Chemicals". It is not restricted to toxic chemicals but is expected
to be involved with any existing or new industrial chemical. A third objective
is to control the chemical industry in the prevention of pollution.
Some people have said that this Act is to fill the gaps in existing EPA
legislation. It supplements the capability to deal with water pollution and
it increases the capability to deal with air pollution. It's concerned with
waste disposal, with products and product labeling, and with all aspects of
the chemical production industry. The fourth, and last major function of the
law, is to screen chemicals for hazard before they are produced commercially.
Every new chemical must be subjected to analysis by EPA. EPA might determine
that the chemical may be manufactured, might decide that it should not be
manufactured or may place any one of many different kinds of restrictions on
production of the chemical. These restrictions might be in the location of
production facilities, in the quantity of production, in the use, in the
method of production, or any limitation that would appear to make the chemical
safer—either safer for the worker, or safer for citizens.
147
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RESEARCH ASPECTS
The law generally provides that research may be performed in any area
necessary to support the purposes of the Act. It specifically describes
health effects research but it states that epidemiological research, which
normally has been the responsibility of the OSHA (the Office of Safety and
Health Administration) shall also be a responsibility of EPA: Testing in
this respect is biological, either for effects on human health (directly from
environmental experience or occupational experience); or through toxicological
tests using rats, mice, and other experimental animals.
The new priorities in research that were not handled by EPA before
include the authority to control and thus investigate manufacturing processes.
We may determine that a chemical which currently is being manufactured in
open production can be produced only in closed systems. We may say that the
particular kind of piping that's being used in production may not be used,
but rather another kind of pipe must be used. We may say that the chemical
may be produced for only a short period of time and then there must be time
to clean the machinery. The law is quite broad in terms of its capability of
looking at manufacturing processes.
In terms of testing for health effects, the authority extends to providing
that industry do all of the testing, and industry must test for all effects
that EPA requires. The testing procedures, however, have one important
control—that control being that the EPA Administrator must find that there
is a reason to test, and this finding may be challenged in court. The Admin-
istrator must decide what testing will be performed. When the test results
are delivered, he may not continue to ask for additional tests. He must know
what he wants when he asks for testing the first time.
A new type of research, at least of increased importance, is what one
might call discovery monitoring. Instead of attempting to emphasize quality
assurance and accuracy of data, the law says that the EPA should be interested
primarily in the presence of the chemical in the environment; and, that
generally all contact with chemicals in the environment should be reduced.
Therefore emphasis in research needs to be in the direction of being able to
detect substances which were not detected before; the development of new
methods, the extension of capabilities for analyses into new areas and the
ability to detect chemicals that were not previously recognized as problems.
Epidemiology, I've mentioned, is a new area of emphasis. Formerly the
responsibility of OSHA, epidemiology research is expressly described as being
important under the Toxic Substances Act. To provide coordination, the Act
says that the EPA, if it plans to engage in epidemiological research, needs
to coordinate that activity with NIOSH, the National Institute of Occupational
Safety and Health, the research arm of the Department of Labor in this area.
Another area that becomes more important in EPA is the area of terres-
trial ecology. EPA has had several laboratories, including the Corvallis
laboratory, the one at Gulf Breeze, the one in Narragansett, and the one in
Duluth, that are concerned with aquatic ecotoxicology. The Act says that we
must protect the terrestrial environment with equal vigor as with the aquatic
148
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environment. Thus, the Agency will have to increase its activities in terres-
trial ecology.
The last new area of research is in the area of exposure. The objective
of the Act could only be met by reducing exposure to all chemicals. The
information gathered from the previous studies and from existing studies is
to be combined so that interpretations can be made with regard to exposure.
In the evaluation of chemicals, the assessment of chemical hazard becomes
very important. It is expected that the EPA will follow the procedure of
collecting chemical dossiers, that is documentation of the various kinds of
effects; and that in many cases, industry will be required to prepare these
dossiers. Testing will be done to complete the dossiers and in general, they
will contain packages that include physical/chemical data. These data will
include production and trends, procedures for manufacturing the chemical, use
and consumption processes, health information, chemical fate and transport
information, environmental effects, and exposure. These data must be collect-
ed, not only by a chemical manufacturer who produces the chemical in the
United States, but also by importers who bring chemicals into the country.
The importers must, therefore, either obtain the data directly from foreign
companies or they must arrange to have the foreign company submit the data
itself. We've been told that probably the foreign manufacturer would prefer
to present the data directly to the EPA rather than presenting that data to
the importer, who on receipt of production data might be tempted to sell the
information on the manufacturing procedures to someone in the United States.
For the purposes of protection of confidentiality they, the manufacturers,
may submit the data directly to the Office.
There are some problems that must be faced in the testing of chemicals.
For example, the problem of cost-sharing. In the United States if the EPA
were to require a complete battery of tests, those tests might cost half a
million dollars. If a company in the United States were required to spend
that money on a chemical and the data were made available, this might affect
the value of a chemical to be imported from another country. Therefore,
we're very much concerned with this type of requirement and the ways in which
cost-sharing may be made effective. In the United States cost-sharing must
take place between the companies that are involved in U. S. production. If
the companies themselves do not reach agreement, the EPA Administrator is
required to bring about agreement or to impose a cost sharing solution.
The information under the Toxic Substances Act may be of interest to
OSHA, the Food and Drug Administration, the Department of Transportation, the
Department of Interior, or an other agency which has to do with chemical manu-
facture. The Act contains considerable information on the ways in which
information shall be shared within the U. S. government and with foreign
governments. If the United States produces a chemical and then regulates
that chemical's production, not only are we responsible for notifying U. S.
Agencies, but also any importing country must be notified of the hazard of
the chemical that it is receiving. As is usual practice, the United States
may ban production within the United States, for sale within the United
States, and still permit production for sale overseas. In cases of this
kind, a formal notification of the toxicity of the chemical and the status of
regulation must be sent to the foreign government.
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In all of the regulations that are written under the Toxic Substances
Act, economics must be taken into account. We must take into consideration,
in writing the regulation, the cost of the testing being required, any poten-
tial delay in production of the chemical, and other economic factors. No
undue or unnecessary hardship may be imposed on the prospective manufacturer.
There is a provision in the law which permits economic issues to go to litiga-
tion; that is, manufacturers may appeal EPA's ruling, based on economics.
ENFORCEMENT
Enforcement of the Act is primarily through the Regional offices of EPA.
The EPA's ten regions have substantial authority for inspection and for
assuring that all of the data are presented to EPA. Inspection may be carried
out within the normal court procedures but it may also'be carried out unexpect-
edly by entering a plant without a warrant. The Act provides for access to
company records and inspection of production facilities without warning.
Violations under the Act are severely penalized. Any person who knowingly
fails to produce information or fails to make that information available on a
required time scale is subject to $25,000 a day criminal penalty and $25,000
a day civil penalty.
This Act is primarily concerned with individual chemicals and categories
of chemicals. The Japanese Toxic Substance Law deals specifically with PCBs
(polychlorinated biphenyls). Our law also deals specifically with PCBs. We
are required to have labeling and disposal regulations by the end of 1977;
and by the end of 1978, PCBs are banned completely from production and new
use. We will still have the same problem that everyone has in dealing with
PCBs currently in transformers and in determining how they should eventually
be disposed. There remains the problem of refills of transformer fluids when
required and there is no longer any PCB production. However, the law clearly
requires that PCBs no longer be produced for sale.
The Toxic Substances Control Act will also be used to regulate chloro-
fluorocarbons. We are banning aerosol use of chlorofluorocarbons in December
of 1977 and we're considering the non-aerosol use for possible regulation in
the future. A regulation is being developed for polybrominated biphenyls
(PBB) as a result of the accident with PBBs in Michigan and the exposure and
loss of agricultural products and their impact on human health. American
companies were thought not to be producing PBBs, but it was discovered that
PBBs are produced in the United States for sale overseas. One of the deci-
sions we must make is whether to continue to produce PBBs for export or to
ban them completely.
INTERNATIONAL IMPLICATIONS
Perhaps the most important regulation for Japanese industry, as well as
the U. S. industry, is the regulation requiring an inventory of chemicals.
We've had the benefit of the Japanese experience with a list of chemicals.
We are preparing our own list. We think that our list will be substantially
larger than the 20,000 chemicals produced on the list by METE. The list we
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expect to have will include at least 34,000 chemicals, but it may be much
larger. We anticipate that there will be approximately 1,000 new chemicals
per year to add to the list of existing chemicals. Rather than follow the
general practice of the European countries of the OECD or the practice in
Japan of dealing with only the new chemicals, we expect to deal more with old
chemicals than the new ones. We think this approach is valid from the stand-
point that there is a greater volume of old chemicals which have wider and
more general use than the newly developed ones. Because of the large volume
of old chemicals and the expected steady addition of new ones, we are inter-
ested in the development of common testing practices.
In negotiations with OECD and with the Common Market and in bilateral
meetings with with Japan and other countries, we are considering that we
should be able to reach full agreement in the near future on the initial
physical and chemical tests that should be performed. Through OECD we have
established a series of testing work groups. These testing work groups will
be meeting in the lead countries, and in February of 1978 in the United
States, to consider at least five major categories of tests. There will be a
working group that is concerned with chemical/physical data; a work group
concerned with persistence testing; another work group with ecotoxicology
(ecosystem ecology testing); a fourth group which would be concerned with
short term tests (eye tests, acute exposure tests, and subchronic toxicity
tests); and a final group would be concerned with long term toxicity testing.
The procedures developed must be sufficiently common to harmonize the regula-
tion of the chemicals in such a way that we would not be presenting non-
tariff trade barriers. We want to use the Act in such a way that we do not
decrease the possibility of international trade in chemicals.
In international activities we are particularly concerned with the capa-
bility to share epidemiological experiences. We think that we should learn
from the Japanese spills of mercury and cadmium and the information that
you've gained from those spills. We would like to have a rather complete
study of the water below the now closed Azo dye factories in the Osaka area.
We would like to see a system where full information is obtained and shared
about the U. S. spills, such as the accidental release of dioxin in Kansas
City and of polybrominated biphenyls in Michigan. In other words, we would
like to be able to gain information from any industrial accident or related
exposure to chemicals. We believe that it would be most effective internation-
ally to share toxiological testing capabilities. There's a shortage of
toxicologists and we believe sharing the capability internationally will be
of mutual benefit. We would like to use similar hazard assessment procedures
such that a chemical dossier prepared in Japan would be similiar to a chemical
dossier prepared in the Common Market countries or in the United States.
We find much to admire in the administration of the Japanese Law. We
are impressed by your ability to look at chemicals and declare certain ones
safe for production. We have been told that of the chemicals considered,
approximately 189 have been declared safe and 19 are considered to require
chronic toxicity testing. Your development of programs for the use of biode-
gradation tests and bioaccumulation tests are looked on with great interest.
The procedures that you follow in testing chemicals through a series of steps
are the type we would like to follow. We think the cooperation that could be
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developed and has been developed in this committee and in other committees is
very important. We value greatly such cooperation and we look forward to
productive and useful exchange of information, both here and in subsequent
sessions.
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MITIGATION FEASIBILITY FOR THE KEPONE-CONTAMINATED
JAMES RIVER, VIRGINIA
K. M. Mackenthun, M. W. Brossman,
J. A. Kohler, and C. R. Terrell
Criteria and Standards Division
Office of Water and Hazardous Materials
U. S. Environmental Protection Agency
Washington, D.C. 20460
ABSTRACT
As the result of carelessness in production and in
waste disposal the health of Kepone production workers at
Hopewell, Virginia, has been jeopardized and a 70-mile
reach of the James River has been contaminated by this
hazardous and persistent pesticide. In addition, Chesa-
peake Bay is threatened. EPA's Kepone Mitigation Feasi-
bility Project was undertaken to address the threat posed
by Kepone contamination and to recommend possible cleanup
action. Responsibility for the project was assigned to
the Criteria and Standards Division, Office of Water
Planning and Standards, in EPA, with support from an
Energy Research and Development Agency laboratory (the
Battelle Pacific Northwest Laboratories), the U. S. Army
Corps of Engineers, EPA's Gulf Breeze Environmental
Research Laboratory and the Virginia Institute of Marine
Science. The project involves: (1) assessment of the
biological and ecological impact of Kepone through
literature search, laboratory and field studies; (2)
assessment of the potential sources of continuing con-
tamination by inflows into the James River; (3) sampling
and evaluation of the contamination in the James River;
(4) modeling the movement of contaminants; and (5) evalua-
tion of potential conventional and nonconventional methods
for mitigating the problem. Preliminary results indicate
that continuing inflows of contamination into the James
River exist, and that there •'S no evidence of any degrada-
tion in the pesticide or indication that natural causes
will substantially alleviate the problem in the foresee-
able future. While some mitigation methods now look
promising, their cost-effectiveness must be evaluated.
A full report of EPA's Kepone Mitigation Feasibility
Project and recommendations for alleviating the Kepone
contamination problem is scheduled for March 1978.
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INTRODUCTION
The hazard of highly persistant, toxic substances contaminating large land
and water areas is a problem of continuing concern worldwide. The Kepone prob-
lem in Hopewell, Virginia, was especially serious because of deleterious ef-
fects on the health of production workers. Two years after the closedown of
the production site, the disposal of Kepone production residues is still not
resolved. Inflows of Kepone into the James River and the levels of contamina-
tion in the river remain as high as those measured a year ago.
EPA's Kepone Mitigation Feasibility Project, undertaken at the request of
the Governors of Virginia and Maryland, is designed to determine the nature,
extent and effects of Kepone contamination in the James River System and to
provide recommendations for mitigating actions.
BACKGROUND
Kepone was produced at Hopewell by the Allied Chemical Corporation from
1966 to early 1974, after which the Life Science Products Company, under con-
tract to Allied, continued Kepone production. The plant was closed by Virginia
public health officials in July 1975, after workers were diagnosed to have
Kepone poisoning. Eventually more than 70 individuals developed ailments
ranging from slurred speech and loss of memory to liver damage and sterility.
In July 1975, the Center for Disease Control at Atlanta, Georgia, ana-
lyzed blood samples of a Life Science Products Company employee and found a
Kepone blood level of 7.4 ug/g. The State of Virginia in early August 1975
asked the EPA Health Effects Research Laboratory in North Carolina to institute
a human and environmental sampling program to ascertain the extent and effects
of Kepone contamination. EPA responded and reported its results on December
16, 1975. Kepone blood and sebum skin sample residues were found from 0.2 to
7.5 ug/g from 28 hospitalized Life Science workers, and in one worker's hos-
pitalized wife. Kepone was found in the James River water samples at concen-
trations of 0.1 to 4 ug/1 and in fish and shellfish at concentrations of 0.1
to 14 ug/g. Some water and shellfish samples were collected 40 and 64 miles
from Hopewell, respectively. Action levels, recommended by EPA, for the con-
demnation of foods sold in the marketplace are 0.3 ug/g for finfish, oysters
and clams, and 0.4 ug/g for crabs. Bottom sediments and sewage sludge con-
tained significant Kepone concentrations. Prior to Life Science's closure,
the Hopewell sewage treatment plant's digesters were made inoperable on several
occasions because of the toxic effects of Kepone. Soils around the Life
Science plant site had Kepone residues as high as 20,000 ug/g. Air samples
gathered between March of 1974 and April 1975 from a State sampler station
located approximately 200 meters from the Life Science plant contained residues
ranging from 0.2 to 50 ug/m3 of air.
On August 20, 1975, the EPA Regional Office in Philadelphia, Pennsylvania,
issued an order to Life Science Products Company to stop sale, use or removal
from its premises of Kepone. As a result of Kepone contamination, the Governor
of Virginia closed the James River to fishing on December 18, 1975. On February
154
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3, 1976, a stop sales order was issued to Allied Chemical's Baltimore facility,
which served as the distribution point for the Kepone produced in Hopewell. A
chronology of the major events to May 1976 is shown in Figure 1. The May 1976
Federal Court indictment led to a $13.2 million fine against Allied Chemical.
The Kepone incident has had a disastrous effect on the Life Science
workers and poses continuing hazards from Kepone contaminants in the soil,
water and sediments. In addition to its human health and ecological damage,
the Kepone incident has had an immediate economic impact on the James River
fishermen and threatens an important seed oyster industry. The James River
supplies approximately 90 percent of all seed oysters in Virginia, of which
50 percent are exported to other States.
KEPONE PROPERTIES AND USE
Kepone, technical grade Chlordecone (C10C1100), is a white-to-tan crystal-
line solid and sublimes at 350 degrees centigrade with decomposition. It is
slightly soluble in water, soluble in acetone, ethers, and nitrobenzene, but
less soluble in benzene, toluene, hexane, and petroleum ether. It can be dis-
solved by dilute alkali. Kepone during pyrolysis gives substantial quantities
of hexachlorocyclopentadiene. When it reacts with phosphorus pentachloride,
"Mirex" is produced, which is another chlorinated pesticide. Mirex may undergo
a slow photodechlorination reaction when exposed to sunlight to produce Kepone
and related compounds (1).
Kepone was used in the United States as an ant and roach killer. It is
used in other countries on potato beetles, banana bore worms and fire ants.
Approximately 90 percent of Life Science's Kepone production was exported.
Kepone is related to the chemicals DDT, Aldrin and Dieldrin, all of which have
been restricted in their use by the Environmental Protection Agency. Kepone
registration has been cancelled except for the use of small percentages of
Kepone by pesticide formulators in ant and roach traps until present stocks
are used.
KEPONE CONTAMINATION IN THE HOPEWELL AREA
Hopewell, Virginia, situated at the junction of the James and Appomattox
Rivers, has manufactured chemicals since the World War I era. Today, it is a
major chemical preparation center of 23,300 people (Figure 2).
The amount of Kepone lost from the Life Science operation has been esti-
mated to be as much as 91,000 kg (200,000 Ib.) with Kepone production esti-
mated to be approximately 770,000 kg (1,700,000 Ib.) (2). These losses were
derived largely from four basic sources: (1) atmospheric release, (2) waste-
water discharges; (3) wastewater releases from spills, equipment malfunctions,
and production batches that failed to meet specifications; and (4) tank truck
and solid waste loads dumped at the Hopewell landfill. The magnitude of these
sources cannot accurately be quantified. Spillage from the production line and
intentional discharges constitute the biggest nonquantifiable source of
releases.
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Kepone Chronology
Year Others
Allied Chemical
Corporation
Life Sciences
Products Company
asp)
City of Hopewell, State of Virginia
Virginia
Environmental
Protection Agency
(EPA)
Occupational Safety
and Health
Administration
(OSHA)
1959
Kepone first regis-
tered as a pesticide
with USDA. Toxicity
information included
in registration
shows Kepone causes
"ODT-like tremors."
1960
to
1972
Kepone found to
cause growth and re-
productive effects
and tumors.
1971 : EPA assumes
responsibility for
registration and
regulation of pes-
ticides from USDA.
December 1970: Oc-
cupational Safety
and Health Act
creates OSHA.
1966: Manufacture
begins at Allied
plant in Hopewell.
1973
Allied terminates
Kepone production.
LSP Incorporates in
Virgina and con-
tracts with Allied
to produce Kepone
from raw material
supplied by Allied
for sale exclu-
sively to Allied
at the rate of 0.4
to 1.5 million
pounds per year.
October: Applica-
tion to Water Con-
trol Board for a
permit to discharge
municipal waste
water, claims no in-
dustrial charges
enter sewage treat-
ment plant.
1974
February: After
citation for fail-
ure to obtain air
pollution permit
LSP applies for
and receives per-
mit. Repeated
violations of
standard for par-
ticulates require
installation of
baghouse in
October.
April: After dis-
covery that the
sewage treatment
plant is malfunc-
tioning because of
decimation of bac-
terial digesters by
Kepone. Hopewell
asks EPA for tox-
icity and treat-
ment information.
February: Virginia
cites LSP for fail-
ure to obtain air
pollution permit
for S02 and partic-
ulates. (See LSP
listing.)
October: Water Con-
trol Board grants
Hopewell waste
water permit with
no requirements for
monitoring or limit
on Kepone dis-
charges, but soli-
cits information
and recommendations
for treatment of
Kepone contamina-
tion from EPA. (See
Hopewell listing.)
November: EPA pro-
vides information
requested by Water
Control Board on
toxicity of Kepone
and recommends a
limit of 0.4 part
per billion in water
for municipal plant
intake.
September: Former
LSP employee files
a complaint about
working conditions
at LSP. OSHA's
toxicological in-
formation does not
indicate severe
hazard so com-
plaint handled as
discrimination
case.
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Kepone Chronology
Year Others
Allied Chemical
Corporation
Life Sciences
Products Company
(LSP)
City of Hopewell, State of Virginia
Virginia
Environmental
Protection Agency
(EPA)
Occupational Safety
and Health
Administration
(OSHA)
1975 July: Hopewell phy-
sician submits
blood sample of LSP
employee to Center
for Disease Control
(Atlanta) for anal-
ysis. CDC finds
Kepone blood level
of 7.4 ppm and
notifies Virginia
Department of
Health.
August: Washington
Post reports ill-
ness of Kepone
workers and LSP
closing.
March 20: Expecting
new regulations.
Allied applies for
registration under
FIFRA(b) of LSP as
manufacturer of a
pesticide.
April 11: Allied
letter to EPA as-
serts that under
existing regula-
tions Kepone pro-
duced at LSP is a
pesticide compo-
nent; therefore,
LSP is not subject
to FIFRA's pesti-
cide producer reg-
istration require-
ment.
July: Virginia
State Health De-
partment orders LSP
to stop production.
Limited production
continues into Sep-
tember.
December: EPA anal-
yzes air samples
obtained earlier by
Air Pollution Con-
trol Board and
finds Kepone among
the pollutants col-
collected.
April: City agrees
with Water Control
Board to clean and
repair water treat-
ment facilities by
June.
June: Above dead-
line not met.
June: State amends
Hopewell waste
water permit to
require pretreat-
ment of effluents
from LSP. Require-
ments apparently
ignored.
July: Virginia De-
partment of Health
receives report of
Kepone blood levels
in LSP employees.
State inspects LSP
and orders it to
close.
December: Governor
of Virginia closes
James River to fish
and shellfish har-
vesting.
March: EPA begins
to investigate
whether LSP has vio-
lated FIFRA (a) re-
quirement that all
pesticide products
and producers regis-
ter with EPA.
August: EPA begins
human and environ-
mental sampling of
Hopewell area.
September: EPA in-
forms FDA of James
River contamination.
December: EPA re-
ports results of
sampling program.
August: OSHA offi-
cials first visit
Hopewell, where
Kepone production
continues despite
state order to
close. OSHA cites
LSP and the two LSP
copartners for 4
violations, in-
cluding failure to
prevent employee
exposure to harm-
ful levels of
Kepone. The total
proposed penalty
for the violation
is $16,500.
1976 February: Medical
College of Virginia
reports that 14
former LSP em-
ployees are prob-
ably sterile.
National Cancer
Institute releases
study results in-
dicating Kepone is
carcinogenic.
March: FDA estab-
lishes action
levels for seizure
of contaminated
fish and shellfish.
May: Allied Chemical, Life Sciences, and the City of Hopewell
are indicted in federal court on 1,096 criminal counts, in-
cluding conspiracy to defraud EPA and violations of federal
water pollution laws.
February: EPA recom-
mends action levels
to FDA for seizure
of contaminated fish
and shellfish.
March: EPA sends for-
mulators of Kepone-
containing products
a notice of presump-
tion against regis-
tration of these
products.
January: OSHA re-
opens 1974 com-
plaint of former
employee of LSP.
(a) Information obtained from EPA, Senate Agriculture and Forestry Committee (hearings before the Subcommittee on Agricultural Research and General
Legislation, Jan, 22, 23, 26 and 27, 1976).
(b) Federal Insecticide, Fungicide, and Rodenticide Act, as amended.
Figure 1. Kepone Chronology. Environmental Quality-1976: The Seventh Annual
Report of the Council on Environmental Quality, Washington, D.C.
-------
in
oo
(' CITY POINT \
JORDAN POINT
COUNTRY CLUB,
SCALE IN MILES
Figure 2. Hopewell , Virginia and Bailey Bay/James River ^from u.5. «cuiuy
Washington, D.C.)
-------
Grand Jury testimony by former Life Science employees indicated there were
three major sources of spills. The first source was routine spills of over-
flows and boil-overs. The second was discolored Kepone or batches not meeting
Allied specifications which were dumped directly into the sewer. Employee
testimony suggests that this occurred approximately once a week in the early
plant operation and once a month thereafter. The final source was bypassing
or dumping of filter tanks. These loads of Kepone caused the Hopewell sewage
treatment plant to be inoperable on several occasions. Figure 3 shows the Life
Science plant after closure. During cleanup and after the Life Science closure,
Kepone-contaminated sludge from the sewage treatment plant was placed in an
asphalt gravel-lined, earthen-diked lagoon near the plant. Estimated volume of
the lagoon is 5,700 cubic meters (1.5 million gallons) with the liquid portion
containing approximately 2 mg/1 Kepone and the solids 200 to 500 pg/g (3).
Remnants from the dismantled Life Science plant were placed in a clay-lined
pit in the landfill adjacent to the sewage treatment plant (4).
KEPONE MITIGATION FEASIBILITY PROJECT
The Governors of Virginia and Maryland, in the Fall of 1976, jointly re-
quested that EPA evaluate the Kepone contamination in the James River and its
tributaries, and explore corrective or mitigative actions. In response to this
request, a two-phase project plan was adopted. Phase I involves a detailed
assessment of: (1) suspected continuing sources of Kepone contamination; (2)
the fate and transport of Kepone in the James River system; (3) the current and
long-range effects of Kepone contamination on the biota; and (4) an evaluation
of mitigation and removal methods. The results of Phase I are to provide a
basis for action recommendations. Following a review of the Phase I recommen-
dations by EPA and the States of Virginia and Maryland, Phase II may involve a
decision to: seek funding for a major cleanup or mitigation program; proceed
with pilot testing of alternative corrective and mitigative actions; or with-
hold action because of unfavorable cost/benefit assessments.
An allocation of $1.4 million was made for the Phase I effort. A compre-
hensive work plan was developed and support studies were arranged with the
U. S. Army Corps of Engineers, the Energy Research and Development Agency
(ERDA), the EPA Gulf Breeze, Florida, Environmental Research Laboratory, and
the Virginia Institute of Marine Science. Under the interagency agreement with
the Norfolk, Virginia, District Corps of Engineers, engineering studies to con-
tain, stabilize, or remove Kepone-contaminated sediments have been conducted.
Eighteen alternatives to mitigate the Kepone problem have been evaluated. In
addition, the Corps of Engineers has contracted with the U. S. Fish and Wild-
life Service to investigate the wetland ecosystem to compare plant and animal
distribution patterns with unaffected areas. Under the interagency agreement
with ERDA, the ERDA/Battelle Pacific Northwest Laboratories are: (1) conduct-
ing sampling and analysis of the suspected sources of Kepone contamination to
the James River; (2) obtaining in cooperation with the Virginia Institute of
Marine Science, water quality, sediment, hydrological and other data on the
James River; (3) modeling the transport and fate of sediments in the river;
(4) evaluating nonconventional Kepone mitigation techniques; and (5) assessing
the ecological impact of the current Kepone contamination and possible mitiga-
tion approaches. The EPA Gulf Breeze Laboratory provided scientific data and
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(Top) Life Science Products in Hopewell, Virginia, produced Kepone
until July 1975 when it was closed down by the state. (Bottom) The
collection box shown has a drainpipe with cracks in its side, allowing
Kepone to leak into the city's sewer system. Such contaminating con-
ditions led to the poisoning of many of the plant's employees (Photo
credit: Virginia State Department of Health, Dr. Robert S. Jackson)
Figure 3. Life Science Products Company
160
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analysis on the effects of Kepone on the estuarine biota, including bioaccumu-
lation, and distribution and fate of Kepone. The Virginia Institute of Marine
Science is collecting field data on the James River. Results of these investi-
gations are being integrated into models of Kepone movement and sediment trans-
port by Gulf Breeze and ERDA/Battelle Laboratories, respectively (Figure 4).
Key milestones in task plans included presentation and discussion of prelimi-
nary results at a Kepone Seminar in September 1977, draft reports from the
supporting agencies in November, a draft Kepone Mitigation Feasibility Report
in January 1978, and a final report with recommendations in March 1978. The
final report will be the basis for considering the Phase II efforts.
KEPONE ANALYTICAL PROCEDURE AND STANDARDIZATION
Selection of a reliable, well-accepted analytical procedure for detecting
and establishing levels of Kepone was essential. Accordingly, the procedure
developed by EPA at Research Triangle Park, North Carolina, was adopted (5).
This procedure accommodates analyses of river sediment, soil, water, shellfish,
and finfish. Rigorous extraction techniques utilizing the Soxhlet apparatus
and the Polytron tissue homogenizer are required for the complete removal of
Kepone from the samples. Finfish tissues are the most difficult to analyze.
For this type of substratum, a preliminary cleanup by gel permeation chroma-
tography removes most of the lipid material followed by a micro Florisil
column elution to eliminate polychlorinated biphenyls (PCBs). Cleanup of
shellfish and other environmental samples is accomplished with a micro Florisil
column only. Electron capture gas chromatography is used to analyze the sample
extracts. Recoveries of Kepone from fortified samples averaged 84 percent or
greater.
To assure quality control between investigating laboratories, the Kepone
Mitigation Feasibility Project instituted a standardization procedure involving
the distribution to participants involved with Kepone analyses of samples con-
taining Kepone concentrations unknown to them. Four sample groups were dis-
tributed: (1) control without Kepone; (2) control known to have interfering
compounds; (3) James River Kepone-contaminated sample; and (4) fortified sample
of known Kepone quantity. Presently the results are being analyzed and recom-
mendations for improved laboratory procedures will be instituted, if necessary.
TOXICITY
Kepone is toxic to animals causing liver enlargement, impaired reproduc-
tion, and endocrine disturbances. In mice it is accumulated mainly in the
liver, brain, kidney and body fat (6, 7). It also has been reported to be
carcinogenic in mice and rats (8).
Kepone is extremely hazardous to the reproductive capacity of male birds
by exerting an "estrogen-like" effect. Male ring-necked pheasants fed Kepone
at 50, 100, or 150 pg/g developed adult female plummage and had abnormal testes
with malformed sperm (9). Degeneration and abnormality of testes also has been
noted in Japanese quail in immature, as well as adult males (10, 11, 7). In
some cases testes were greatly enlarged with distended seminiferous tubules
filled with fluid and cellular debris disrupted germinal epithelium and de-
creased spermatogenesis. In all other cases testes were severely atrophied in
161
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G
BIOLOGICAL MOVEMENT
and LOADING
E
BIOLOGICAL UPTAKE
s \
^
^ k.
F
BIOTRANSPORT in
JAMES RIVER
H
BIOLOGICAL EFFECTS
M c
SOLUBLE TRANSPORT
SEDIMENT TRANSPORT
CHEMICAL/PHYSICAL
MOVEMENT & LOADING
EXPERIMENTAL DEGRADATION
MICROBIOLOGICAL
BIOTRANSPORT OUT
VAPORIZATION
of JAMES RIVER
STRUCTURAL &
CONVENTIONAL
DREDGING
BIOLOGICAL FATE
& EFFECT
NATURAL REMOVAL
of KEPONE
COST & EFFICICY of
ALTERNATIVE REMOVAL/
MITIGATION TECHNOLOGY
0
ECOLOGICAL PROFILE
of JAMES RIVER
^**
P
PROBLEM ASSESSMENT &
ECOLOGICAL RESPONSE
MODEL
NONCONVENTIONAL REMOVAL
or TREATMENT METHODS
U
RECOMMENDED PLAN FOR
CORRECTION of KEPONE
INFLOWS
ENVIRONMENTAL IMPACTS &
BENEFITS OF ALTERNATIVES
RECOMMENDED PLAN FOR
KEPONE REMOVAL/MITIGATION
in the JAMES RIVER ESTUARY
Figure 4. Kepone mitigation feasibility project components.
-------
a manner similar to testes of estrogen-injected birds. Cows fed 5.0 pg/g
Kepone in their diets for 60 days excreted 90 ug/g of Kepone in their milk 35
days after the end of the feeding experiment (12). Dr. Rita Colwell, Univer-
sity of Maryland, maintains that there may be several bacteria which may de-
grade Kepone.
The EPA Gulf Breeze, Florida, Environmental Research Laboratory has found
that (13, 14, 15, 16, 17):
Oysters, grass shrimp and certain species of fishes have bioac-
cumulated Kepone from 425 to 20,000 times the concentrations in the
surrounding water;
Kepone-contaminated oysters, when placed in Kepone-free water can
depurate approximately 90 percent of the accumulated Kepone in four
days, but fish may require 3 weeks or more to lose 30 to 50 percent
of the Kepone.
Fifty percent photosynthetic reduction for four marine unicellular
algae exposed to Kepone for seven days ranged for 0.35 to 0.60 mg/1;
Acute 96-hr LC50 toxicity of Kepone on spot, sheepshead minnow, grass
shrimp and blue crab ranged from 6.6 to greater than 210 ug/1, with
6.6 ug/1 being associated with spot.
Sheepshead minnows (Cyprinodon variegatus) during chronic toxicity
tests exhibited backbone structural abnormalities (scoliosis),
darkening of the posterior one-third of the body, hemorrhaging near
the brain and on the body, edema, fin-rot, uncoordinated swimming
and cessation of feeding; and
Fish fry from Kepone-exposed parent stock, developed abnormally and
died even when reared in Kepone-free water. Five weeks after ferti-
lization of sheepshead minnow eggs containing Kepone, the juvenile
fish retained as much as 46 percent of the Kepone originally present
in the eggs.
Kepone recently has been tested under the auspices of the National Cancer
Institute (8). Osborne-Mendel rats and B6C3F1 mice were fed Kepone in their
diets for 80 weeks and developed malignant liver tumors (hepatocarcinomas)
when the diet contained 20 and 40 ug/g Kepone.
HOPEWELL AREA SAMPLING
A comprehensive sampling plan for Bailey Creek, Gravelly Run, and other
water courses, plus the terrestrial areas of the City of Hopewell, the muni-
cipal sewage treatment plant area, and the municipal landfill, was established
to quantify inflows of Kepone to Bailey Bay and the James River system. Soil
samples were taken at various locations in the Hopewell area to determine the
extent of Kepone contamination in the watersheds. The sampling points were
located to give insight to the possible significance of contamination of the
163
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James River from terrestrial sources. Representative sampling sites in the
Hopewell/Bailey Bay area are shown in Figure 5 with the results of this sam-
pling shown in Figure 6.
The levels of Kepone contamination at the Life Science production site
have dropped substantially from the 1975 levels of 10,000 to 20,000 ug/g.
Results of field investigations indicate about 200 ug/g Kepone in soil samples
in the vicinity of the now unused production plant. Most soil samples in the
surrounding Hopewell area, however, are close to a level of 0.25 ug/g. Kepone
as high as 386 ug/1 has been found in storm runoff from the production plant
site. Area test wells close to the plant site contained 0.8 ug/1 Kepone.
Homogenized one-third meter core samples of Bailey Bay sediments have been
found to have Kepone concentrations of 12.6 ug/g near the mouth of Bailey Creek
to about 0.1 ug/g in the outer portions of the Bay. Sediment Kepone concen-
trations generally are highest along the shore of Bailey Bay, as would be
expected from the settling action produced by James River flow. Within sedi-
ment cores from Bailey Bay near the debouchment of Bailey Creek, there was
great variation in the vertical levels of the core. At the core's surface
there was 0.81 ug/g Kepone; at the 7-inch level, 65.14 ug/g; and at the 10-inch
level 0.45 ug/g. This phenomenon remains unexplained.
Kepone is preferentially associated with the larger organic particles in
the sediment. This observation coincides with those made by Allied Chemical
and Virginia Institute of Marine Science and suggests that detrital matter may
be an important role in the binding and transport of Kepone (18, 19).
JAMES RIVER SAMPLING
The purpose of the James River sampling plan was to obtain field data in
the James River for input to and adjustment of the sediment and contaminant
transport model and for derivation of fractionation coefficients for dissolved
and sediment sorbed Kepone in the James River.
This original sampling plan consisted of data acquisition at ten transects
along a 70-mile reach of the James River and estuary. Three stations were
located on each transect (one station in the flow channel and one station each
on either side of the flow channel on the subtidal flats or channel margins).
One to three depths were sampled per station (near surface mid-depth and near
bottom). Four transects were located in the freshwater reach of the James
River between River Mile (R.M.) 45 and 70, three transects in the saline water
or estuarine section between R.M. 0 and 35, and three transects in the turbid-
ity maximum between R.M. 35 and 45.
The sampling data gathered in the field include meteorological and hydro-
logical information; channel and flow characteristics, physical and chemical
characteristics of suspended load and bed sediments; and water quality charac-
teristics. Kepone analyses were conducted on water, suspended load and bottom
sediment samples. Figure 7 shows the relative sediment concentrations of
Kepone for the 70-mile reach of the river sampled in 1976.
164
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CTl
Poythress
Run
Science
• Sediment Core Samples
(Homogenized Core Analyzed)
^Sediment Core Samples
(Individual Segments Analyzed)
T Heavy Metals and Broad
Spectrum Organics Analyses
• Filtered Suspended Sediment
Water Samples, and Particle
Size Distribution (2 sets)
Figure 5. Representative sampling sites in the Hopewell , Virginia area.
-------
cr>
.02
•45 ^Jordan Point
.10
.29
,25
Poythress
1 Run
Science
Figure 6. Soil/sediment Kepone concentrations (yg/g)
in the Hopewell, Virginia area.
-------
SEDIMENT CONCENTRATIONS
ppm Kepone
Figure 7. James River sediment concentrations from Hopewell, Virginia to Newport News, Virginia. August 1976
-------
Kepone sediment concentrations in the James River ranged from a level of
1.0 to 9.0 pg/g near Hopewell and in Bailey Bay to 0.1 to 0.99 pg/g in a reach
immediately downstream and in a reach of more quiet waters in the river's mid
portions to 0.02 to 0.09 (jg/g in other reaches.
MODELING MOVEMENT OF KEPONE IN THE JAMES RIVER
One of the critical questions to be addressed by the feasibility study is
whether the Kepone contamination from the James River is moving downstream and
threatening the Chesapeake Bay and if so, at what rate and what are the expected
levels of contamination.
A model has been developed to address this problem. The model simulates
the movement and resulting distribution of Kepone in the 70-mile reach from
Hopewell to the mouth of the James River. The data for the model have been
derived from a wide range of previous sampling programs, together with those
conducted in this project.
The model combines parameters for a riverine system and an estuarine
system reflecting: seasonal flows; tidal fluctuations; vertical and horizon-
tal mixing of both water and sediments; the effects of the turbidity maximum;
sediment transport; and sorbtion/desorbtion of Kepone from sediments.
Outputs of the model include:
(1) time-dependent, longitudinal and lateral distributions of sediments
and Kepone;
(2) sediment transport for three sediment types: cohesive sediment,
noncohesive sediments, and organic materials, and;
(3) Kepone transport for the dissolved portion and for the particulate
portion which has Kepone attached.
At this time, complete results of the modeling effort are not available;
however, preliminary findings tend to confirm the movement of higher levels of
Kepone concentration downstream.
CONVENTIONAL MITIGATION TECHNIQUES
The Norfolk District Office of the Corps of Engineers is evaluating all
potential dredging technology, as well as methods to reduce and control resus-
pension of concomitant secondary pollution. Subsequent to this evaluation the
Corps was asked to develop conventional removal or mitigation alternatives for
reducing the Kepone contamination in Bailey Creek and Bailey Bay and to prepare
an environmental assessment addressing these alternatives.
POTENTIAL DREDGING TECHNOLOGY
In the United States today there are basically two categories of dredges,
the scoop or bucket action type and the hydraulic suction type. Often con-
siderable turbidity is created at the dredge site during operation of these
168
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types of dredges. Bucket action or scoop dredges used in the L). S. include
the dragline, the dipper, the grab bucket or clamshell and the endless chain
dredge. Hydraulic suction type dredges consist of a surface mounted centri-
fugal pump which sucks water and suspended material through a pipeline, floated
on pontoons, to a disposal site or holding containers which, when full, trans-
port the spoil to a disposal site.
The hydraulic suction dredge can be fitted with various mechanisms at the
suction pipe inlet which facilitate sediment removal. These mechanisms include
rotary cutters or cutterheads, auger-type cutter heads or high pressure water
jets. Mud shields or dustpans are used on some hydraulic dredges in conjunc-
tion with the water jets to reduce secondary suspension at the suction inlet.
However, these dredges collect only 10 to 30 percent solids, cause consider-
able sediment agitation when mechanical cutterheads are used, and induce
secondary pollution at the receiving site due to high water content in the
dredged material. Consequently, without the use of sediment control measures
such as silt curtains, turbidity barriers or "diapers", conventional dredges
pose a serious threat for aggravating an existing, but possibly dormant pollu-
tion problem. Some types of hydraulic dredges in the U. S. include the cutter-
head pipeline, the suction pipeline, the dustpan, the hopper hydraulic dredge,
the sidecasting dredge, and the Mud Cat.
Dredging technology in foreign countries surpasses that of the U. S. ,
especially in Japan where serious problems with toxic substances caused the
development of a dredge which was designed to remove contaminants rather than
to excavate river channels. A significant advancement in dredging technology
for removing contaminants was the improvement of a pneumatic dredge. The
pneumatic or "Pneuma" dredge, originally developed in Italy, uses hydrostatic
head pressure and compressed air to remove contaminated sediments. By applying
a vacuum to a pneumatic dredge the Japanese were able to utilize the dredge
in shallow water, thereby eliminating the constraint of needing a high hydro-
static head pressure. This dredge is called the Oozer dredge.
Specific advantages for using the pneumatic dredge system especially for
contaminant removal include:
(1) continuous and uniform flow;
(2) practically no wear since there are no mechanisms in contact with
the abrasive mixture except for the self-acting spherical rubber
valves;
(3) removes up to 60 to 80 percent solids by volume;
(4) particularly suited for dredging polluted material since it does not
disturb the bed while dredging and therefore avoids secondary
pollution; and
(5) can be readily dismantled for transport over highways.
169
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The following are examples of the pneumatic-type dredges: Pneuma (Italy),
Pressain Sand-Pump (Germany) and Oozer (Japan).
The Japanese have also advanced other aspects of dredging technology
through the development of a "cleanup" hydraulic dredge, an antiturbidity
system for hopper dredges and the water-tight grab bucket.
ALTERNATIVE CONVENTIONAL MITIGATION MEASURES FOR CAPTURING, STABILIZING, OR
REMOVING KEPONE IN GRAVELLY RUN, BAILEY BAY, AND BAILEY CREEK
In considering any dredging activity, it is important to address the
method of conveyance and the disposal area for the dredged material. These
components need to be considered as an integrated system and not as separate
components. With the complication of contaminated sediment the problem greatly
magnifies. Considering the Hopewell situation the Corps developed 18 alterna-
tive measures to manage the Kepone contamination in Gravelly Run, Bailey Creek,
and Bailey Bay. The Corps' alternatives consisted of diking, dredging, cover-
ing or sealing, impoundment, channelization and diversion, or combinations
thereof. After evaluating each alternative some were eliminated from further
consideration because they offered no further benefits over less costly options.
It must also be noted that treatment of water leaving Bailey Bay or Bailey
Creek is necessary and these costs have not yet been considered in the alter-
natives.
Bailey Bay, near Hopewell, is situated between Jordan Point to the east
and City Point to the west. It is approximately 2.4 miles long, 1/2 mile in
width, and encompasses about 800 acres. Both Bailey Creek and Gravelly Run
discharge into Bailey Bay. The Bay, for the most part, is shallow. At extreme
low tides, almost the entire bay bottom is exposed. A few small vegetated
islands exist in the northern portion of the Bay.
Bailey Creek, which discharges into Bailey Bay, has a drainage area of
approximately 20 square miles. The creek is 3.2 miles in length from the
mouth to Route 156, about 700 feet wide at the mouth, and about 25 feet wide
at Route 156. Two bridges cross the creek, Route 156 and Route 10. Of the
20 square-mile drainage area, 14 square miles is upstream from Route 156.
Both the east and west banks of Bailey Creek are highly wooded throughout the
study area.
Gravelly Run also drains into Bailey Bay and has a drainage area of about
1 square mile. The Corps is considering 4 basic mitigation options for
Gravelly Run:
(1) A dam and treatment plant at the mouth of Gravelly Run to treat flows
up to and including the 100-year flood level. The treatment plant
would be designed for 50 to 150 million gallons per day (MGD), de-
pending on the detention time allotted. This option would require
72 acres and cost $1.5 million, excluding treatment costs.
(2) Dam mouth of Gravelly Run, exclude spillway and divert all existing
flow to Bailey Creek for treatment. Costs would be $2 million,
excluding treatment costs.
170
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(3) Seal contaminated areas, elevate stream channel, rip rap creek bed
and construct control structure at mouth. Costs would be $1.8
mi 11 ion.
(4) Dredge all contaminated material from Gravelly Run. Twenty acres
would need clearing prior to dredging, and a treatment plant would
be needed to treat dredging effluent.
Four similar alternatives are still being considered for Bailey Creek:
(1) A dam and treatment plant at the mouth to treat flows including the
100-year flood level. The cost would be $14 million, excluding
treatment costs.
(2) Seal contaminated sediments, rip rap creek bed, elevate channel and
construct control structure at mouth. This option would cost $20
mil 1 ion.
(3) Dredge all contaminated material from Bailey Creek. 410 acres would
need clearing and 2.2 million cubic yards of material would need
excavating.
(4) Dam and divert upland uncontaminated watershed flows to reduce size
of dam and treatment plant needs at the mouth. The upstream reser-
voir would require 1,405 acres of land. Diversion to Chappell Creek
would require pumping and $35 million while diversion to Bailey Bay
in sealed pipe paralleling the existing flows would cost $23 million.
The options for Bailey Bay are more significant because of the area's
size and the amount of contaminated sediments. The Corps is considering five
alternatives for Bailey Bay:
(1) Dredge contaminated material from Bailey Bay and dispose of spoil at
an estuarine or upland site. No final spoil site or costs have been
determined. Dredging to obtain Kepone levels of 0.3 pg/g would re-
quire removing 2.8 million cubic yards of sediment while dredging to
0.1 ug/g levels would require removing 4.3 million cubic yards of
material. Treatment of elutriate water would be required in both
cases.
(2) Construct a levee from 1 mile east of City Point to Jordan Point a
distance, of 14,250 feet. This levee would contain all the runoff
from Gravelly Run and Bailey Creek, would be 10 feet above mean sea
level (MSL) and would cost $8 million, excluding treatment. This
option is illustrated in Figure 8.
(3) Construct high dams on Bailey Creek and Gravelly Run, divert flows
from Gravelly Run to Bailey Creek. Treat runoff at Bailey Creek and
store dredged material from Bailey Bay behind the dam on Bailey Creek.
Treatment requirements would be from 100 to 150 MDG depending on
retention times. This option requires 930 acres and would cost more
than $21 million, excluding treatment costs.
171
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t\>
V .£ JORDAN
CHEMICAL
HOPEWELL
BAILEY BAY
GRAVELLY
RUN
'BAILEY CREEK.
SEWAGE
TREATMEN
LANT
SCALE IN FEET
2000 0 2000 4000
Figure 8. Engineering plan for damming Bailey Bay to contain Kepone.
-------
(4) Construct a 10-foot high MSL levee 1 mile east of City Point to
Jordan Point and use area behind levee for spoil disposal from
dredging maintenance or from other sources of contaminated material.
The cost of this option is $8 million, excluding elutriate treatment
costs.
(5) Construct a levee from Jordan Point to Bailey Creek and utilize area
behind levee for disposal of dredged material from Bailey Creek and
Gravelly Run. Seal area, cover with topsoil and seed with grass.
Elutriate treatment, dredging, and construction costs have not been
determined, but the levee would be 15 feet above MSL.
The Corps recommends using a dragline or bucket dredge for dredging oper-
ations becuase of their availability. However, cost estimates and the feasi-
bility of using the Oozer dredge are being explored.
Three types of treatment, being investigated for the runoff and elutriate
waters in all the above alternatives, are: conventional water purification
with sand filtration, activated carbon, and ultraviolet/ozonalysis. Costs are
presently being determined for the various projected flow rates.
The Corps' options for the Bailey Creek/Bailey Bay area may seem expen-
sive. However, a prime objective of the project is to stop or control continu-
ing inflows of Kepone from Hopewell. The Corps of Engineers is also inves-
tigating conventional mitigation measures to remove the Kepone located in the
James River proper. The widespread distribution of the Kepone in the estuary
may make it feasible to address only known "hot spots" with conventional re-
moval methods.
NONCONVENTIONAL MITIGATION TECHNIQUES
Since there are high costs and inherent secondary pollution problems
associated with the removal of contaminated sediments by dredging, Battelle
Pacific Northwest Laboratories is examining nonconventional removal, neutrali-
zation, and isolation techniques. This phase of work focuses on evaluating
alternatives to dredging, as well as treatment and/or fixation processes com-
plementary to dredging for application to Kepone-contaminated sediments in the
James River System. Three types of alternatives are being studied: (1) those
which could be used to fix dredge spoils for disposal; (2) those which could
be employed to treat elutriate or spoil slurries; and (3) those which could be
applied j_n situ as substitutes to dredging.
Dredge spoil fixation techniques are designed to prevent further water or
air pollution by using stabilizing agents capable of solidifying wastes and
immobilizing contaminants. Candidate materials include asphalt, tar polyole-
fins, epoxy resins, silicates, and elemental sulfur. The desirability of any
one fixation agent is based on the characteristics of the contaminant to be
bound as well as the conditions of disposal which may lead to a breakdown of
the structure of the fixed mass.
173
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Each fixation agent being evaluated has been subjected to two types of
standardized tests: (1) a short-term elutriate test; and (2) a longer term
leach test. All fixation work was performed on a "standard" sediment prepared
from a homogenized Bailey Bay sediment sample. The Kepone concentration in
the samples was 1 ug/g. Only commercially available fixation agents were em-
ployed and an effort to include all companies currently marketing fixation
processes was made. However, not all companies chose to participate and some
companies have not yet submitted their final results.
The early results shown in Table 1 do not include all involved companies.
Accordingly, the preliminary conclusions are not final and may not reflect the
full potential of using fixation agents. To date, none of the samples exhibits
any clear retardation of Kepone loss. In fact, several agents appear to en-
hance Teachability. For the silicate agents increased Teachability is believed
to reflect the high pH associated with the fixation process. (Since Kepone is
much more soluble under high pH conditions, the fixation process is actually
releasing Kepone from sediments.) The gypsum system appears to physically
break down when left standing in water A preliminary evaluation of asphalt
binders was made, but these could not be easily mixed with wet sediments unless
heated. The mixing problems with asphalt binders may constitute excessive
costs and equipment requirements for the volumes of sediments involved.
If dredging is employed to restore the James River System, there will be
a need for the capability to treat elutriate, leachate, and/or the entire
dredge spoil slurry to prevent subsequent escape and movement of low-level
contamination. The applicability of various elutriate treatment approaches
depends completely on the physical-chemical properties of the Kepone, as well
as the nature of the liquid stream to be treated. For the purposes of the
work conducted, candidate approaches were divided between biochemical and
physical-chemical mechanisms.
A review of the literature indicated no evidence of microbial degradation
of Kepone. However, as previously mentioned, Dr. Colwell indicated she may
have identified some Kepone-degrading bacteria. Dr. Ralph Valentine of Atlantic
Research, Alexandria, Virginia, identified six strains of fungi and molds which
yielded 13-40 percent degradation of Kepone over a two-to three-week period.
Best results were obtained when no additional carbon source was available to
the organism.
A wide range of alternatives exists for the physical-chemical destruction
of Kepone. Approaches being investigated are the use of oxidizing chemicals
and processes utilizing electromagnetic waves of various frequencies.
Regarding the latter category, no data were found with respect to the
effect of sunlight on Kepone degradation. Work with Mirex showed that it was
not subject to photolysis to a large extent unless it was placed in an alipha-
tic amine solution. The decomposition product appeared to be a mixture of
monohydride derivatives of Kepone.
To test the applicability of photolysis to Kepone, 10 mg/1 in solutions
of 100 and 10 percent amine were exposed to a sun!amp for one hour (Table 2).
174
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TABLE 1. KEPONE CONCENTRATIONS IN LEACHATE SOLUIONS (pg/1)
Leach Period
Fixation
Company A
Company B -
Company C -
Blank 1
Blank 2
Type (a)
Silicate 1
Silicate 2
Silicate 3
Silicate 4
Silicate 1
Silicate 2
Gypsum
1
1.04
1.34
1.33
0.39
0.07
0.05
0.52
<0.06
0.117
4
0. 99
2.64
1.88
0.54
0.08
0.05
0.47
<0.06
0.04
24
1.01
0.90
1.31
1.00
0.094
0. Ill
0.91
0.076
0.104
in Hours
168
1.81
1.30
1.42
1.18
0.166
0.157
0.91
0.058
0.081
336
1.74
1.18
1.04
1.27
0.524
0.306
0.050
0.11
672
2.09
0.78
1.02
1 41
0.30
0.27
0.22
(a) Company names will not be identified until data are finalized and firms
have been informed of their products' performance.
TABLE 2. EFFECTS OF SUNLAMP IRRADIATION IN AMINE SOLUTIONS
Solvent System
Hexane
Ethanolamine
Tri ethyl ami ne
Ethyl enedi ami ne
Strength of Solvent (%)
10
100
10
100
10
100
10
100
Kepone
1 Hour
1,640
3,700
2,230
6,520
54
2,240
1 ,715
<23
Concentration
(ug/i)
23 Hours
6,040
530
7,970
2,530
18,620
477
117
175
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Tests with ethylenech'amine show promise at higher concentrations. Work is cur-
rently underway to identify degradation products, assess the effectiveness of
other secondary amines, and evaluate the concept for application to contami-
nated soils.
Gamma radiation can affect degradation, but required doses are considered
too high. A residual of 0.14 ug/g (88 percent removal) was obtained when sedi-
ment with 1.2 ug/g Kepone was subjected to 144 megarad.
Work has also been performed on ozone-enhanced ultraviolet oxidation.
Preliminary evaluations with a stock solution of 5.172 mg/1 produced residuals
of 20.9 |jg/l and 46.7 |jg/l over 1.5- and 2-hour exposures, respectively.
Because of the need for the UV to penetrate any slurry being treated, a second
set of tests is being performed with waters having a high particulate load.
Chemical oxidation tests conducted with chlorine dioxide and ozone showed
that neither oxidant was effective in degrading Kepone. A second set of eval-
uations using chlorine dioxide and sunlight is now underway. Work is also
underway at Envirogenics to determine the effectiveness of their catalytic
reduction process for dechlorination, but data are not available at this time.
l£[ situ processes as a category are the newest of the approaches to re-
moval/mitigation of in-place toxic materials. As such, they are typically not
as fully developed as other approaches, but may offer benefits as yet unmeas-
ured. Several of the more promising options were selected for testing in the
laboratory.
Preliminary findings indicate that biological approaches hold little
promise for use in areas where Kepone contamination is of concern. The six
strains of fungi and mold identified by Atlantic Research appear to be subject
to dominance by natural bacteria in sediments. Therefore, application jji situ
may be hampered by poor growth if not loss of viability.
Although Kepone accumulation by biological systems followed by subsequent
harvesting has been suggested, preliminary findings indicate that Kepone re-
moval from the water in Bailey Bay by algae or vegetation would be slight due
to the low amounts of dissolved Kepone in the water. (The partition coeffi-
cient between water and sediment for Bailey Bay was found to be 10 4).
To gain information on rooted plant uptake from the sediments, barley
uptake was studied in the laboratory. Battelle found that barley did not
translocate Kepone to the stem and leafy parts. The Kepone attachemnt mechan-
ism to roots is likely to be direct adsorption rather than biological uptake.
This work with barley does not preclude rooted plant uptake possibility by
other plants but, to date, no evidence supports rooted plant uptake.
Artificial means of accumulation may be more promising. Natural sorbents
such as activated carbon and synthetic sorbents such as the macroreticular
resins have been shown to be effective in concentrating organics similar to
Kepone. In preliminary laboratory investigations, several commercial agents
were found to have a partition coefficient 100 times that for Bailey Bay sedi-
176
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merits. It was further determined that with the incorporation of magnetite into
the structure of the sorbent beads, these particles could be spread through an
area of contaminated sediments and be selectively retrieved after a period of
accumulation.
Preliminary laboratory results for the first time period are presented in
Table 3. The 863 and XAD-2 sorbents appear quite effective. They also display
continued effectiveness beyond the initial two-week period. There is some
concern, however, that such a process will be kinetically limited. The sorbent
can quickly remove dissolved Kepone from interstitial waters, but this is only
a minute portion of the total quantity in the system. Subsequent removal re-
quires desorption and migration to the Sorbent. To study the nature of such
movement, vertical columns of contaminated sediment were designed and a sorbent
layer placed on the surface. After eight weeks, 0.5-inch segments were sec-
tioned and analyzed independently to determine the depth of influence. Results
are presented in Table 4. Sorbent 863 appears to have been effective at least
to a depth of 3.5 inches. Additional analysis at increasing depths is present-
ly underway to determine the ultimate depth of influence.
Physical retardation of Kepone to the water column through the use of an
impermeable covering barrier or an i_n situ stabilization technique was also
investigated. The use of a 2-mil sheet of polyethylene in the Bailey Bay area
may be applicable, but venting to relieve pressure from anaerobic generation
of gases may reduce effectiveness. The effectiveness of silicate-based agents
for in situ stabilization is still understudy.
In summary, no fixation agents have been found satisfactory to date, but
several still need to be fully evaluated. Apparent problems with the more
common silicate-based agents stem from Kepone desorption at the higher pH
"levels. At least three candidate elutriate/slurry processes have shown
promise to data: UV ozonolysis; biodegradation with selected fungi and molds;
and amine-assisted photolysis. Retrievable synthetic sorbent and polymer films
both appear applicable as Jjn situ approaches at this time. None of the elu-
triate treatment processes evaluated has shown potential for use jjn situ. The
investigation results of the nonconvertional mitigation techniques are sum-
marized in Table 5.
Again, it must be emphasized that the information presented to date is
preliminary and that many analytical data are yet to be evaluated and numerous
tests must still be completed. Final recommendations will be made only after
these have been concluded and viewed coT-ectively.
Allied Chemical, in separate studies, indicated at the Kepone Seminar on
September 20 and 21 that there were promising results obtained in using anthra-
cite coal to immobilize Kepone through j_n situ selective sorbtion (2). They
also reported the destruction of some Kepone residues through the use of caus-
tic solutions at elevated temperature .and pressure. Further efforts to coor-
dinate these investigations with our study are underway.
177
-------
TABLE 3. EFFECTIVENESS OF SORBENTS IN ACCUMULATING
KEPONE FROM BAILEY BAY SEDIMENTS
2 wk Exposure
4 wk Exposure
XADZ^
**$>'
FILTRASORBCCj)
300
Magnetic Carbon
Blank
Cone, in
Sediment
After 2 wk,
M9/1
0.80
1.18
0.89
1.21
1.56
1.56
Apparent
Removal , %
49
24
43
22
0
0
Cone, in
Sediment,
M9/1
0.53
1.06
0.72
1.06
1.23
1.56
Apparent
Removal , %
66
32
54
32
21
(a) Product of Rohm and Haas
(b) Product of Diamond Shamrock
(c) Product of Calgon
TABLE 4. EFFECT OF SURFACE APPLICAION OF SORBENTS WITH DEPTH
Sorbent 863
(a)
XAD-4
(b)
Depth, in.
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Blank
Kepone
Content,
H9/9
0.262
0.211
Kepone
Content,
M9/g
0.079
0.060
0.066
0.328
0.045
0.299
0.040
Apparent
% Removal
70
77
75
—
79
--
81
Kepone
Content,
fjg/g
0.291
0.209
0.119
0.155
0.053
0.174
0.233
0.058
Apparent
% Removal
—
20
55
41
75
34
--
73
(a) Product of Diamond Shamrock
(b) Product of Rohm and Haas
178
-------
TABLE 5. SUMMARY OF PRELIMINARY RESULTS AND STATUS OF NONCONVENTIONAL CANDIDATE ALTERNATIVE EVALUATIONS
Approach
Option
Results
Status
Fixation
Elutriate
Slurry Treatment
In situ
Silicate Bases
Gypsum Bases
Epoxy Bases
Sulfur Bases
Asphalt
Amine Photolysis
Y Radiation
UV-Ozonolysis
Ozone
Chlorine Dioxide
Catalytic Reduction
Biological Degradation
Biological
Retrievable synthetic
sorbents
Polymer films
High pH characteristics produce
expensive leachate concentrations
Breakdown in water, ineffective
Too difficult
sediments
to apply to wet
Some degradation rated with
specific amines
Effective at excessive doses
Effective on clear solutions
Ineffective
Ineffective
Promising strains of fungi and
mold identified
No significant degradation,
bioaccumulation bad, harvesting
too slow from sediments
Specific media highly effective
Feasible
Some agents still to be
tested
Rejected
Tests not complete
Tests not complete
Rejected
Testing degradation products
and applicability
Rejected
Testing in natural waters
Rejected
Testing in presence of
Data not yet available
Deserves further
consideration
Rejected
Tests are continuing
Assessing probable effective-
ness, long-term implications
-------
REFERENCES
1. Carlson, D. A., K. D. Konyha, et aj., 1976. Mirex in the environment:
Its degradation to Kepone and related compounds. Science 194:939-
941.
2. Ferguson, W. S. , September 12, 1975. Personal Communication.
3. Sterrett, F. S. and C. A. Boss, 1977. "Careless Kepone". Environment,
19(2):30-36.
4. Walz, D. H. and H. T. Chestnut, Jr., 1977. Land disposal of hazardous
wastes: An example from Hopewell, Virginia. In: Proceedings of the
Third National Ground Water Quality Symposium, Environmental Protec-
tion Agency. EPA-600/9-77-014:195-200.
5. Moseman, R. F. , H. L. Crist, et a±. , 1977. Electron capture gas chroma-
tographic determination of Kepone residues in environmental samples.
Arch. Environm. Contam. Toxicol. 6:221-231.
6. Huber, J. J. , 1965. Some physiological effects of the insecticide Kepone
in the laboratory mouse. Toxicol. Appl. Pharmacol. 7:516-524.
7. McFarland, L. Z. and P. B. Lacy, 1969. Physiologic and Endocrinologic
effects of the insecticide Kepone in the Japanese quail. Toxicol.
Appl. Pharmacol. 15:441-450.
8. Anon., 1976. Report on carcinogenesis bioassay of technical grade Chlor-
decone (Kepone), U. S. Department of Health, Education and Welfare,
Washington, D.C.
9. DeWitt, J. B. , D. B. Crabtree, et aj. , 1962. "Effects of Wildlife". In:
Effects of Pesticides on Fish and Wildlife: A Review of Investiga-
tions During 1960. U. S. Fish an Wildlife Service Circular No. 143.
10. Atwal, 0. S. , 1973. Fatty changes and hepatic cell excretion in avian
liver: An electron microscopical study of Kepone toxicity. Jour.
Comp. Pathol. 83(1):115-124.
11. Eroschenko, V. P. and W. 0. Wilson, 1975. Cellular changes in the gonads,
liver and adrenal glands of Japanese quail as effected by the insec-
ticide Kepone. Toxicol. Appl. Pharmacol. 31:491-504.
12. Smith, J. C. and F. S. Grant, 1967. Residues of Kepone in milk from cows
receiving treated feed. Jour. Econ. Entomol. 60:925-927.
180
-------
13. Hansen, D. J., A. J. Wilson, Jr., et al., 1976. Kepone: Hazard to aquat-
ic organisms. Letter to the Editor.
14. Walsh. G. E. , K. Ainsworth, et a]_. , 1977. Toxicity and uptake of Kepone
in marine unicellular algae. Chesapeake Sci. 18(2): 222-223.
15. Schimmel, S. C. and A. J. Wilson, Jr., 1977. Acute toxicity of Kepone to
four estuarine animals. Chesapeake Sci. 18(2):224-227.
16. Hansen, D. J. , L. R. Goodman, et al. , 1977. Kepone: Chronic effects on
embryo, fry, juvenile and adult sheepshead minnows (Cypri nodon
variegatus). Chesapeake Sci. 18(2):227-232.
17. Bahner, L. H. , A. J. Wilson, Jr., et_ al_. , 1977. Kepone bioconcentration,
accumulation, loss and transfer through estuarine food chains.
Chesapeake Sci. 18(3):229-308.
18. Williams, R. J. , 1977. "Kepone Bound to James River Sediment", Informal
Report 77-1, Allied Chemical Corp., Project 0946.
19. Huggett, R. , D. Haven, et a]_. , 1977. "Kepone Sediment Relationships in
the James River (Abstract), Interim Report to U. S. Environmental
Protection Agency, Gulf Breeze Laboratory.
20. Paterson, A. R. , R. J. Williams, et cfL , 1977. "Allied Chemical Kepone
Investigations'1. Paper presented at Kepone Seminar II, Eaton,
Maryland, September 20, 21, 1977.
181
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HUDSON RIVER - PCB STUDY DESCRIPTION AND
DETAILED WORK PLAN
Edward G. Horn and Leo J. Hetling
State Department of Environmental Consevation
Albany, New York 12233
INTRODUCTION
On September 8, 1976 the New York State Department of Environmental Con-
servation and the General Electric Company signed an agreement bringing to a
close the action brought against General Electric relating to the discharge
of polychlorinated biphenyls (PCBs) into the Hudson River. This paper presents
a detailed description of the Department of Environmental Conservation's
program for implementing Section 3 of the settlement which is the portion
related to monitoring and reclamation of the river.
BACKGROUND
Polychlorinated biphenyls (PCBs) were first manufactured in 1929 and
their chemical properties were soon discovered to be ideal for a number of
industrial uses. They are extremely stable chemically and biologically,
conduct electricity very poorly, and possess a very low solubility in water.
In the United States, they have been used for a wide variety of purposes,
most heavily as a heat transfer fluid and insulator in heavy electrical
equipment. But, these same chemical properties create a significant biological
hazard.
This hazard might have gone unnoticed had it not been for an industrial
accident in Japan that has come to be called the Yusho ("rice oil disease")
incident. In 1968 this disease (manifest primarily as a serious skin disorder)
was traced to PCB contamination of rice oil during its manufacture. Since
that incident, more research has turned up rather frightening facts.
Yusho victims are still exhibiting symptoms of the poisoning and, even
though not exposed to additional PCBs, they still have high levels of PCBs in
their blood and other body tissues. Several deaths among the victims have
been associated with malignant cancers, though it is not possible to conclu-
sively state that the PCBs caused the cancers. Recent evidence shows that
the rice oil and tissues of Yusho patients also contained polychlorinated
dibenzofurans (PCDFs). PCDFs are more toxic than PCBs. It is therefore not
possible to conclusively associate the symptoms of this incident with PCB
poisoning1 2.
183
-------
Experiments with laboratory animals, including monkeys, however, confirm
that many of the symptoms associated with Yusho are directly related to con-
sumption of PCBs and persist in the bodies of all experimental animals long
after they are removed from diets containing PCBs. In addition to deaths
being noted at high doses, liver tumors have also been induced in mice and
rats. An exhaustive summary of these effects can be found in the recent
Criteria Document for PCBs (1976) published by the Environmental Protection
Agency1 and a report published by the United States Department of Health,
Education and Welfare2.
As a result of accumulating research on PCB toxicity, the United States
Food and Drug Administration (FDA) has set standards for allowable levels of
PCBs in various foods3.
THE PCB SETTLEMENT
Polychlorinated biphenyls were discovered to be a problem in the Hudson
River in 1975. The United States Environmental Protection Agency and Fish
and Wildlife Service analyzed samples of fish taken from the river and found
that PCB concentrations were higher than the FDA limits by a substantial
margin. The fish could thus not legally be shipped for interstate sale.
Acting on this and additional evidence that the Department of Environmental
Conservation (DEC) had itself collected, charges were brought against the
General Electric Company (GE) for polluting the river with the toxic substance
PCB. Administrative proceedings began on September 8, 1975. On February 9,
1976, after weeks of testimony and a substantial record of several thousand
pages of transcripts, prefiled testimony, reports, studies and other exhibits,
the Hearing Officer, Professor Abraham D. Sofaer, found that DEC had presented
overwhelming evidence of GE's responsibility for high concentrations of PCBs
in the upper Hudson's waters, sediment, organisms and fish. In a 77-page
interim opinion, Professor Sofaer detailed the evidence and the violations4.
It is interesting to note that he found that the unlawful actions were the
consequence of both corporate abuse and regulatory failure by the responsible
Federal and State agencies.
In order to determine the appropriate remedial measures, a second phase
of the hearing was held during the spring and summer of 1976. As a result of
this hearing, a settlement agreeable to all parties was negotiated and final-
ized exactly one year after the administrative proceedings began, September
8, 19765.
The settlement calls for a comprehensive program of at least $7 million
to deal with PCBs in the Hudson River and related environmental concerns.
General Electric was required to reduce its PCB discharges, which had been
averaging about 30 pounds per day until 1972, to one pound per day beginning
September 8, 1976, and to construct a wastewater treatment facility at the
Hudson Falls and Fort Edward Capacitor Manufacturing Facilities. Total PCB
discharges from the plants were reduced to one gram (0.022 pounds) per day by
May 1977.
184
-------
The agreement stipulated that GE was to cease using PCBs by July, 1977
and to perform $1 million of research on several items including the environ-
mental compatabi1ity of any substitute. Finally, GE was required to contribute
$3 million to the Department as its share of additional work to further
monitor the presence and levels of PCBs; to investigate the need for remedial
action concerning PCBs present in the Hudson and to implement such action, if
necessary; and to aid in developing a program to regulate the storage and
discharge of substances hazardous to the environment. New York State was, by
the agreement, obligated to provide an additional $3 million for this work
and the Commissioner of Environmental Conservation became responsible for
overseeing and expediting the required work. An overview of the provisions
of the settlement related to studies of the Hudson River and the Department's
activity to date in implementing them is shown in Table 1.
ADVISORY COMMITTEE
A key provision of the settlement is an Advisory Committee consisting of
independent experts and governmental and private interests which was estab-
lished to "review and make public recommendations to the Commissioner concern-
ing the scope, content, progress and results of the programs, studies and
expenditures."
The PCB Settlement Advisory Committee has been appointed and meets
monthly to carefully evaluate the work in progress and make recommendations
regarding results and further studies.
The relationship of this Advisory Committee to the Department and imple-
mentation of the settlement is given in Figure 1.
THE HUDSON RIVER PROBLEM
In order to better understand the Hudson River PCB problem, it is useful
to know something about the river itself.
For most purposes, the Hudson River Drainage Basin can be divided into
three sub-basins - the Upper Hudson River, the Mohawk River and the Lower
Hudson River as shown in Figure 2.
Table 2 shows, the relative area and water flows for these three basins.
From Ft. Edward to Cohoes the Upper Hudson River is actually a series of low
level dams and serves as part of the Champlain Canal (Figures 3 and 4). The
Mohawk River serves as the eastern portion of the New York State Barge Canal
and joins the Hudson River just above the Troy Dam.
The lower Hudson Basin is tidal over its entire 150 miles (241 km).
Average tides are 4.4 feet (1.4 m) at the Battery, 3.0 feet (1 m) at Beacon
and 4.8 feet (1.5 m) at Troy. Tidal flows at Poughkeepsie have been measured
as 230,000 to 280,000 cfs (6,516-7,932 cms). Dye studies have shown that the
flow actually oscillates with the tide, with a very slow net outflow. Because
of this tidal flow, salt-water intrusion extends quite a distance upriver
185
-------
TABLE 1. OVERVIEW OF TASK REQUIRED BY SECTION 3 OF PCB SETTLEMENT
Settlement Provisions
Department Activity to Date
I. Advisory Committee
The Commissioner of Environmental Conservation
will establish an Advisory Committee consisting of
independent experts, governmental and private
interests which will, at regular meetings review
and make public recommendations to the Commissioner
concerning the scope, content, progress and results
of the program, studies and expenditures for which
provision is made in the agreement.
II. Other Funds
In the event that the funds herein provided for
implementing remedial actions concerning PCBs
present in the Hudson River shall be inadequate to
assure protection of public health and resources,
then the Department will use its best efforts to
obtain additional funds from sources other than GE,
that are necessary to assure such protection.
III. Overall River Program
1. Monitor the presence and levels of PCBs
which have been discharged in Hudson River waters
in water, sediment and biota.
2. Further investigate the need for remedial
action concerning PCBs present in the Hudson River.
3. Implement remedial action if necessary to
protect public health and resources, concerning PCBs
present in the Hudson River.
4. Aid in developing a program to regulate
the storage and discharge of substances hazardous to
the environment if sufficient monies are available
after implementing remedial action concerning PCBs.
IV. Work to be Carried out by GE ($1 million)
GE will conduct research itself or by contract
on the environmental compatibility of its substitute
non-PCB dielectric capacitor fluids ($400,000).
GE will conduct research to be approved prior
to being undertaken by the Commissioner after his
consultation with the Advisory Committee on the re-
moval or treatment of PCBs in supernatant liquids
and sediments from the Hudson River sludge (400,000).
GE will conduct research as specified by the
Commissioner of the effects on the environment of
not more than three substances which may be hazard-
ous to the environment and which are to be selected
by the Commissioner after his consultation with the
Advisory Committee ($200,000).
An Advisory Committee has been formed and it meets
regularly.
No action can be taken until a decision as to the
need for and cost of specific remedial action is
made.
A monitoring program has been developed by the Dept.
and approved by the Advisory Committee. This
program includes contracts for PCB mapping with
Normandeau Assoc., PCB lab analysis with O'Brien
and Gere, and water and sediment transport measure-
ments with USGS. An extensive program of fish,
macroinvertebrate, water and air monitoring by the
Dept. is also underway.
EPA special core study of estuary section was
carried out in December 1976. Lamont-Doherty Lab
will carry out studies to follow-up the results of
this survey.
For more detail see Table 3.
Contracts for studies relating to taking no reme-
dial actions and to removal of PCB contaminated
sediments by dredging are underway (see Figure 5).
The Advisory Committee has approved maintenance
dredging by DOT of a small section of the east
channel of the river near Ft. Edward. An Environ-
mental assessment for this project has been pre-
pared6 7 and approved. Dredging is expected to
take place during the summer of 1977. Experience
from this project will be useful in evaluating and
design of future projects.
No action can be taken until above studies are
received.
No action can be taken until a remedial action pro-
gram is decided upon and implemented; however, an
overall Hudson River research program is being pre-
pared by the Advisory Committee.
A substantial amount of work on the substitute has
been done by GE. A preliminary report8 on the
substitutes has been published and is under review.
The work study plan9 presented by GE has been ap-
proved by the Commissioner on the recommendation of
the Advisory Committee and work is underway.
The Advisory Committee has been asked to recommend
three substances for study. They have established
a subcommittee for this task.
186
-------
COMMISSIONER'S OFFICE
1
L
PCB ADVISORY COMMITTEE
Chairman/Co-Chairman
DEC Project
Manager
Contractors
DEC
Staff
General
Electric
A. Give advice and respond to questions.
B. Managerial direction.
1. Advise DEC about short-term and
long-term planning.
2. Receive and react to periodic
reports from DEC staff.
3. Assist DEC in evaluations.
4. Assist DEC in preparing reports
and recommendations to the
Commissioner.
C. Technical resource.
D. Exchange of information.
E. Managerial direction.
F- Public assess and information,
Figure 1. Organizational chart for the PCB settlement between Genera1
Electric and The Department of Environmental Conservation.
187
-------
TABLE 2. HUDSON RIVER DRAINAGE BASIN AREA AND AVERAGE FLOW
Location
mi2
Upper Hudson Basin 4,634
Waterford
Mohawk River Basin 3,456
Cohoes
Lower Hudson Basin 5,300
Tributaries
Total Hudson Basin 13,390
Area
km2
12,002
8,951
13,727
34,680
Average
ftVsec
7,660
5,630
7,100
20,390
Flow
mVsec
217
159
201
577
From U. S. Department of Interior,
Geological
Survey, Water Resources
Data for New York Water Year 1975, 1976.
188
-------
10 5 0 10 20 30
^^=Z5=
SCALE IN MILES
VER.
I
Figure 2. Hudson River Basin.
189
-------
SARATOGA
CO. (11-04)
1-3250
WARREN
DAM LOCK 5
SCHUYLERVILLE
^DAMU>CK4~/rREN~SSELAER CO.
LEGEND
MILE POINT
USG.S. GAGE
0 I 5
^^sessas
SCALE IN MILES
10
-\
Figure 3. Upper Hudson River Basin.
190
-------
ELEVATION ABOVE MEAN SEA LEVEL (FEET
J> oo ro a
o o o O c
- v^
mm ^^^*""^^A
_ 3
1
•s
- J5
195
-\
.Lock 6 intake
•Thompson Island Dam ^
190
I;
•Lock 6, Fort Miller mgj
Lock 5. ^1 /
185
|\...,
'V
"Northumberland Dam
-Buoy 150
March 14, 1977
September 2, 1976 > — =i
col; j_i .•§ »•£
=5 °*co ^f IOO CM
!» ii «= isf |
i COK~ i GOOD i — JW) — '**^| "H
180 175 170 165
Note: U.S.G.S.
not to scale
.
O O )J
{ J &
ill— JC*
««?. ° °
O Q. ^
.2 o "5
1 ""2H--u!\
-
1 ^ 1
I-? m," | I'^uory
160 155
I5(
MILES FROM THE BATTERY
Figure 4. Upper Hudson River water surface profile.
Fort Edward to Federal Lock.
-------
The 50 mg/1 (0.05 o/oo) salinity fluctuates from 20 mi. (32.2 km) above the
Battery (near Tappan Zee Bridge) to 70 mi. (112.7 km) inland (south of Pough-
keepsie) depending on the freshwater flow.
Testimony given at the hearing clearly demonstrates that although the
levels of PCBs in fish and other animals are alarming, most of the PCBs are
held in the sediments on the river bottom and suspended in the water. Very
little PCBs can be found in the water itself, but because of bioaccumulation,
it is enough to create a serious hazard. "Clean" fish placed in this water
in cages ("live-cars") have accumulated dangerous PCB levels in their flesh
within one month4.
Existing data indicate that the sediments in the section immediately
below the GE discharges at Fort Edward are the most contaminated. General
Electric discharged large volumes of PCBs for at least 25 years. Much of
this probably accumulated in the sediments impounded behind the dams south of
the manufacturing plants. The first dam was located in Fort Edward, but, for
various reasons, it was removed in the late summer of 197310. Some of the
contaminated sediment which subsequently moved downriver has been removed by
Department of Transportation's (DOT) dredging to maintain the Champlain
Canal. Much, however, still remains, particularly in the region between Fort
Edward and the Thompson Island dam.
The essence of the Hudson River problem is that these PCBs are now
slowly leaching back into the river and if no action is taken, may continue
contaminating the river and its biological system far into the future. It is
also possible, however, that the contaminated sediments may be covered or
moved by nature to a section of the river where they may no longer present a
problem or that they may have so spread out over the entire length of the
river that no action is possible.
THE PLAN OF STUDY
Although research prior to and since the court proceedings demonstrates
a serious problem does exist with respect to PCBs in the Hudson River, the
complete scope of the problem and the appropriate remedial action are not
clear. The State plan adopted is a complex program to ascertain the serious-
ness and precise location of PCB contamination in the Hudson River and to
evaluate the cost, environmental as well as financial, of any remedial action.
This program has been formulated by DEC, approved by the Advisory Committee,
and is now underway (Figure 5). A summary of this plan follows.
MONITORING STUDY
In order to define the concentrations anti movements of PCBs in the river
system, a comprehensive monitoring program hasx been developed. The program11
outlined in Table 3 includes monitoring of fish, macro-invertebrates, sediment,
hydrology, wastewater treatment plant input, water and air. Some highlights
of this program are described in the following paragraphs.
192
-------
s
1<
:PT
)76
J/
1<
\N
)77
| 1
W
15
\Y
)77
SI
1<
:PT
377
JAN
1978
MAY
1978
Form
Advisory
Committee
Document existing
monitoring program
and interpret
results
Write RFP
for PCB
Mapping
Write RFP
for PCB
lab work
Send
Review
Select
Devel op
Expanded
monit.
Phase in
expanded program
out FRPs
responses
contractor
Send
Review
Select
out RFPs
responses
contractor
Develop RFP for selection
of
overall dredging consultant
Carry \
Mapping /
Carry \
lab work /
Send out RFPs I
Review responses
Select consultant
Develop RFP for
selection of consultant
for
non-dredging alternatives
Send out RFPs
Review Response Impl
Select consultant con
Develop Develop RFP for
landfill selection of
study consultant for
plan landfill study
Preliminary sampling and
assessment of air sources
of PCB
Send out RFPs
Review Response Imple
Select consultant contr
\
/
r
Carry \
out )
program /
mplement
contract
Cat
ement 01
tract sti
Carry "
out
study t
-ry \
'dy /
Cat
ment 01
act sti
.ry\
idy /
P = Progress Report
F = Final Report
Develop work plans
for other
needed studies
EPA study of
estuary with
Lament follow-up
Develop supernatant work
with General Electric
Implement
contract
Work plan
submitted
and approved
Carry
out
study
Carry
out
study
\
y
NV
/ r
SEPT
1976
JAN
1977
MAY
1977
SEPT
1977
JAN
1978
MAY
1978
Figure 5. Plan for implementation of PCB settlement May 1977.
-------
TABLE 3. PCB-HUDSON RIVER MONITORING PROGRAM
Element
Description of Program
Being Carried Out By
Hydrology
Sediment
10
Groundwater
Water Column
Several additional gaging stations have been established
in the Upper Hudson River.
An extensive number of bed sediment core and grab
samples are being taken in the Upper River to map the PCB
contaminated areas. Some cores are being analyzed for
radioactive Cesium-137 in order to date them.
Several suspended sediment
established to monitor movement
PCB content.
stations have been
of sediments and their
A special study of bed-load sediment transport of PCBs
is underway.
A screening survey of PCB concentrations in the Lower
Hudson River has been completed.
A detailed follow-up study of the estuary sediments and
their PCB concentrations is underway.
Limited groundwater samples are being taken as part of
the study of landfills and dredge disposal sites and as
part of a water supply program.
Water column data will be collected regularly in the
Upper Hudson River. Municipal water supplies using
Hudson River water are being monitored regularly.
USGS
Collections by Normandeau
Assoc.; PCB analysis by O'Brien
and Gere; Cesium-137 analyses by
USGS
USGS
Rensselaer Polytechnic Inst.
EPA.
Lamont Doherty Geological Lab.
Roy F. Weston Asosc; DEC Div. of
Pure Waters; Dept. of Health
USGS; DEC Division of Pure
Waters; DOH
(continued)
-------
TABLE 3 (continued).
Element
Description of Program
Being Carried Out By
Fish
Macro-
invertebrates
Wastewater
Air
Fish will be collected at six sampling locations spread
throughout the river from Still water to the Tappan Zee
Bridge. Most of the sampling will take place in the
Lower Hudson River where commercial fishing interests
are the greatest.
Macroinvertebrate samples will be collected at selected
stations throughout the spring and summer.
A screening program of sewage treatment plant sludges is
planned to determine which if any are potentially con-
tributing significant quantities of PCBs to the river
A sampling network of air quality has been set up in the
Fort Edward area.
Collection by DEC
Fish and Wildlife;
0'Brien and Gere.
Division of
analysis by
Collected by DEC Div. of Pure
Waters and Dept of Health;
analyses by O'Brien and Gere.
Samples collected by DEC Div. of
Pure Waters; analyzed by O'Brien
and Gere.
Samples collected by DEC Div. of
Air Resources and analyzed by
DOH.
-------
The Department's Division of Fish and Wildlife is responsible for a
basic biological monitoring program, and as part of this program, it will be
collecting fish at six sampling locations spread throughout the river from
Stillwater to the Tappan Zee Bridge. Most of the sampling will take place in
the Lower Hudson River where commercial fishing interests are the greatest.
Nine common species are expected to be sampled, mostly during May and June,
but American Shad were taken during their spawning run in April. In addition
to these studies, macroinvertebrates are being sampled throughout the spring
and summer.
These animals, as well as all other materials, will be analyzed for PCBs
by chemists at O'Brien and Gere Engineers of Syracuse, New York. This firm
follows a rigorous quality control program designed and monitored by the
Department of Health and can handle the large number of samples expected
during the program. Before the study is complete, several thousand samples
will be analyzed for PCBs using a gas chromatograph-electron capture detection.
Normandeau Associates, Inc. of Bedford, New Hampshire, was awarded a
contract to map the river bottom measuring the sediment thickness and PCB
content from Fort Edward to the Troy dam, in the region where sediment was
shown to be most heavily contaminated.
In December 1976, the EPA Region II office used a helicopter to collect
Hudson River sediments between Troy and the Tappan Zee Bridge because sampling
in this region had previously been scanty. Results of this survey12 suggested
that the Lower Hudson River also has highly contaminated sediment in at least
four of the twenty sites sampled. To further investigate this possible
problem, a contract is in process with Lament Doherty Geological Laboratory.
Lament Laboratory has collected, analyzed and archived cores in the Lower
Hudson over the past several years. With this unique collection and new ones
from selected sites, it should be possible to get a much better understanding
of PCB levels throughout the estuary portion of the Hudson River.
The United States Geological Survey is cooperating in the study by con-
tinuing their work on sediment transport, particularly during big storms and
the spring thaw. Because high water in the river often moves large volumes
of sediment, PCB measurements provide an indication of whether, and how
rapidly, contaminated sediments in the Upper Hudson move downriver.
Not included as part of the program, but a study that will contribute to
it, is an aquatic ecology and water quality study being done by Equitable
Environmental Health, Inc. for Niagara Mohawk Power Corp.13 as input to their
preparation of an environmental impact statement for possible reconstruction
of a hydraulic dam at Fort Edward.
NEED FOR ACTIVE RESTORATION
All of this new information, and the previously collected data, will be
synthesized and analyzed by three different teams of scientists and engineers.
Two of these teams have been commissioned to study the fate of PCBs in the
river if no action is taken to remove them. The first, the firm of Lawler,
Matusky and Skelly of Tappan, New York, will concentrate on PCB contaminants
196
-------
in the sediments and their movement in the river The second, Hydroscience
Associates, Inc. of Westwood, New Jersey, will concentrate its efforts on the
biological systems and PCB uptake from the water and sediments.
The third team is Malcolm Pirnie, Inc. from White Plaines, New York, who
has been awarded a contract to determine the technical feasibility, engineer-
ing methodology, cost and environmental impact of dredging contaminated sedi-
ments from the river. Although many other methods have been suggested for
removing PCBs from the river, at the present moment, dredging is the only
proven technology which could be applied in the immediate future. Other
techniques would probably take at least five years before they could be used
on the necessary scale. By then, the highly contaminated, and presumably
confined, sediments might well be elsewhere.
Additional information on dredging of PCB contaminated sediments will be
gained as a result of dredging operations planned for the summer of 19776 7.
Although the primary purpose of this operation is maintenance of the canal
system in the Fort Edward area, the work will be closely monitored in order
to evaluate the practically of dredging in PCB contaminated areas.
Dovetailing with Malcolm Pirnie's work, Weston Environmental Consultants
of West Chester, Pennsylvania, are evaluating various landfills and dredge
material disposal sites. If dredging is to be seriously considered, the
dredged materials must be treated and/or placed somewhere. Leaching could
return much of the PCBs back to the river unless adequate precautions are
taken.
The results of these studies are due early in 1978. Hopefully, they
will provide the basis for deciding whether remedial action is desirable. If
dredging is the proper action to be taken, how, when and where should it be
done to provide the greatest removal with the least environmental impact and
least cost? If it appears that dredging is unwise, then what direction
should DEC take in attempting to solve this problem? The answers to these
questions will not be simple but the work being carried out as part of the
PCB settlement will insure that in making them we will have the best scientific
input possib-le.
A multitude of geologists, chemists, biologists and engineers from State
and Federal agencies, private firms and educational institutions are directly
involved in this massive study. A list of the principal groups involved is
given in Table 3. Such a cooperative endeavor, although difficult, is becoming
more commonplace as we realize the necessity of integrating our scientific
and technological knowledge to solve problems of our own making. This study
can be viewed as a test to see if such an effort can succeed.
197
-------
REFERENCES
1. Nisbet, Ian C. T. (1976), Criteria Document for PCBs, EPA 440/76-021.
2. Subcommittee on the Health Effects of PCBs and PBBS (1976), Final Report,
Department of Health, Education and Welfare, Washington, D.C.
3. Department of Health, Education and Welfare (April 1, 1977), Federal
Register 42(63):17487-17494.
4. Sofaer, Abraham D. (1976), Interim Opinion and Order, File No. 2833.
5. Sofaer, Abraham D. (1976), Recommendation of Settlement, File No. 2833.
6. Malcolm Pirnie, Inc., (April 1977), Environmental Assessment of Mainten-
ance Dredging, Champlain Canal, Fort Edward Terminal Channel, Fort
Edward, New York.
7. Malcom Pirnie, Inc. (May 1977), Supplement No. 1, Environmental Assess-
ment of Maintenance Dredging, Champlain Canal, Fort Edward Terminal
Channel, Fort Edward, New York.
8. General Electric Company, (Feb. 28, 1977), Interim Report, Dielektrol
Fluids, Environmental Impact Assessment Program, GE Co., Capacitor Pro-
ducts Dept.
9. Griffen, P. M. and McFarland, C. M. (Feb. 22, 1977), Research on Removal
or Treatment of PCB in Liquid or Sediments Dredged from the Hudson
River, Proposed Study.
10. Malcolm Pirnie, Inc., (1975), Investigation of Conditions Associated
with the Removal of Fort Edward Dam.
11. Mt. Pleasant, R. , (Oct. 26, 1976), Hudson River PCB Monitoring Data Sum-
mary, Past, Present, Proposed, NYS Staff Report.
12. EPA, (Feb. 23, 1977), PCBs in Lower Hudson River Sediments - A Preliminary
Survey 12/11/76-12/15/76.
13. Equitable Environmental Health, Inc., Study Plan for Upper Hudson River
Related to the Ft. Edward and Hudson Falls Dam.
198
-------
AN OVERVIEW OF BOTTOM SEDIMENT PROBLEMS IN SAGINAW
RIVER AND BAY, MARINETTE-MENOMINEE HARBOR, AND
WAUKEGAN HARBOR
Karl E. Bremer
U. S. Environmental Protection Agency
Chicago, Illinois 60604
ABSTRACT
Three waterways in the Great Lakes were selected for
an overview of their current toxicant problems in bottom
sediments. The Marinette-Menominee Harbor has severe
arsenic problems associated with leaching from an adjacent
waste storage area. Polychlorinated biphenyl contamination
of bottom sediments is common to both Saginaw River and Bay
and Waukegan Harbor. Problems related to fish contamina-
tion, proper dredging techniques and disposal of bottom
sediments are discussed.
INTRODUCTION
Each year an average of 10 million cubic meters of bottom sediments are
dredged from lakes and connecting channels of the Great Lakes. Approximately
ninety percent of this volume is dredged to maintain, improve or extend navi-
gable waterways and harbors. The remaining ten percent of this volume as
gravel or sand is used as aggregate supplies to the construction industry.
During the past five years, attention has been drawn to persistent toxic
chemicals, particularly in channels and harbors of the Great Lakes that are
maintained by dredging. As a consequence, the U. S. Environmental Protection
Agency and the U. S. Army Corps of Engineers are concurrently involved in eval-
uation of toxicants in bottom sediments, the persistence of such toxicants, the
interaction with biota, and the most environmentally sound method of dredging
and ultimate disposal of contaminated bottom sediments.
A number of channel and harbor areas in the Great Lakes have been evalu-
ated prior to maintenance dredging. To>
-------
SAGINAW RIVER AND BAY
The Saginaw River is formed by the union the Tittabawasse and Schiawassee
Rivers in the State of Michigan. The Saginaw River flows north into the south-
west end of Saginaw Bay of Lake Huron.
Early in 1972 polychlorinated biphenyls were reported at high levels (1).
PCBs were detected at 5.3 mg/kg in the suspended solids fraction of Saginaw
River water and at 353 mg/kg in wastewater treatment sludge from the Bay City
Wastewater Treatment Plant (2). PCB levels were attributed to a number of
point source discharges on the Saginaw River and its tributaries. Through
abatement activities of the pollution control agency in the State of Michigan
(Michigan Water Resource Commission) PCB discharge to the Saginaw drainage
basin was significantly reduced.
The presence of PCBs in the Saginaw River and Bay resulted in contamina-
tion of fish populations. The Michigan Department of Agriculture detected PCB
"levels in channel catfish in excess of the U. S. Food and Drug Administration
tolerance level of 5 mg/kg. As a result, a ban was issued for commercial cat-
fishing in the inner Saginaw Bay area (3). The continued detection of PCBs in
Saginaw Bay fish indicated that PCBs previously released to sediments continue
to be detected in resident fish populations.
In view of existing PCB problems in Saginaw River and Bay, the U. S.
Environmental Protection Agency was unable to concur with proposed maintenance
dredging and disposal in 1976 until a complete sediment analyses program for
PCBs was undertaken.
The U. S. Environmental Protection Agency (Chicago Office) and the U. S.
Army Corps of Engineers (Detroit District) conducted an intensive survey of
Saginaw River and Bay in October, 1976. PCBs were sampled at 35 locations in
Saginaw River and at 11 locations in Saginaw Bay. PCB concentrations in bottom
sediments ranged from FO. 1 to 22.9 mg/kg for all locations. Samples taken in
the downstream vicinity of the City of Saginaw Wastewater Treatment Plant
ranged from 5.5 to 22.9 mg/kg PCB. PCB concentrations near the Bay City
Waste Water Treatment Plant ranged from 3.5 to 11.8 mg/kg. Sediment samples
obtained in Saginaw Bay had considerably lower PCB concentrations ranging
from 1.3 to 4.2 mg/kg.
Although point sources of PCB discharge have been curtailed along the
Saginaw River, significant concentrations of this chemical remain in the bottom
sediments. A diked disposal facility is near completion in the Saginaw Bay
area and will be used for disposal of these sediments during maintenance and
dredging operations.
MARINETTE - MENOMINEE HARBOR
The Marinette-Menominee Harbor is located on Lake Michigan in the Green
Bay vicinity between the States of Michigan and Wisconsin. The harbor consists
of an approach channel, an inner harbor and a turning basin.
200
-------
In 1973 the U. S. Environmental Protection Agency brought to the attention
of the Ansul Company the potential hazard of a waste storage area adjacent to
the Marinette-Menominee Harbor. The uncovered waste storage area held 45,000
tons of waste salt containing 1,350,000 Ibs. of organic arsenic and approxi-
mately 600,000 Ibs. of elemental arsenic. Because a satisfactory solution for
disposal could not be obtained, Ansul Company reconditioned storage facilities
for the waste salt on a temporary basis.
In November, 1975, the Great Lakes Surveillance Branch of the U. S.
Environmental Protection Agency obtained sediment samples from 10 locations in
Marinette-Menominee Harbor (Figure 1). Sediments at locations 2, 6, and 7 were
primarily silt. Sediments at other locations were primarily sand and gravel
(Tables 1, 2).
Bulk sediment analysis indicate a severe arsenic contamination problem
(Table 3). Extremely high arsenic levels were detected in the turning basin at
location 2 in the vicinity of the Ansul Company. Arsenic contaminated sedi-
ments were found in all samples downstream of the turning basin. Higher con-
centrations were detected along the southern side of the navigation channel.
In addition to arsenic contamination, sediments at location 2 showed in-
creaded concentration of oil and grease, lead, and manganese. These concen-
trations were moderate at other locations with the exception of a high iron
level at location 1.
Macroinvertebrate data and field observations show low numbers and little
diversity of organisms at five locations (Table 4). The absence of macroinver-
tebrates at locations 2 and 7 indicate toxic conditions resulting from elevated
arsenic levels.
Because of high arsenic levels in sediment, the apparent toxicity to
benthos downstream of the turning basin, and the bioaccumulation effects of
arsenic in freshwater biota, sediments downstream of location 1 were classified
as unsuitable for open lake or bay disposal.
During 1977, the Ansul Company received a permit to dispose of the waste
salt in a chemical landfill in Illinois. Disposal of these waste salts is
currently underway.
WAUKEGAN HARBOR
Waukegan Harbor is located on the northwest coastline of Illinois on Lake
Michigan. The harbor is a federal navigation channel and performs an addition-
al function for significant small boat traffic.
In January, 1976, the Illinois Environmental Protection Agency notified
the U. S. Environmental Protection Agency that high concentrations of poly-
chlorinated biphenyls had been detected in the discharge of a local industry
which discharges to Waukegan Harbor. The discharge from the facility had
contributed over 100,000 pounds during a 20 year period to the harbor. The
201
-------
ro
GREEN BAY
.•"MUNICIPAL
< TREATMENT
X. PLANT
-N-
'g ~ DREDGED TO 23 FEET
I ^
DREDGED TO 21 FEET
0 100 1000 3000
SCALE IN FEET
-------
TABLE 1. FIELD OBSERVATIONS AT MARINETTE-MENOMINEE HARBOR
HARBOR: Man'nette - Menominee, Wisconsin and Michigan
SAMPLED: November 5, 1975
Station
No.
MAR 75-1
MAR 75-2
MAR 75-3
ro
o
CO
MAR 75-4
MAR 75-5
repl icate
MAR 75-6
MAR 75-7
MAR 75-8
MAR 75-9
MAR 75-10
Depth
(ft.)
14
26
27
26
23
23
28
27
27
24
31
Color
Dark brown
Dark brown
Dark brown
Brown
Brown
Brown
Dark brown
Dark brown
Brown
Light brown
Brown
Observations
Sample Description
Sand, gravel
Silt
Fine sand, gravel
Silty sand
Sand, medium
Sand, medium
Sandy silt
Fine sand
Fine sand, some silt
Medium sand
Fine sand
Odor
None
Earthy
Slight
earthy
None
None
None
Slight
Slight
None
None
None
Oil
None
Trace
Trace
Trace
Trace
Trace
Trace
None
None
None
None
General Remarks
Bark chips
no organisms
Wood fibers
few organisms
Woodchips, coal
detritus
Woodchips, detritus
no organisms
Detritus, few worms
Detritus, few worms
Wood fibers, detritus
few organisms - 1 bug
Few worms
No organisms
No organisms
No organisms
some detritus
-------
TABLE 2. SIEVE ANALYSIS AT MARINETTE-MENOMINEE HARBOR
HARBOR: Marinette - Menominee, Wisconsin and Michigan
SAMPLED: November 5, 1975
Sieve No.
and
Description
Sediment Size Analysis by Percent at Each Station
MAR 75-1 MAR 75-2 MAR 75-3 MAR 75-4 MAR 75-5
ro
o
Retained on
#10
Medium Gravel
and Larger
Retained on
#20
Fine .Gravel
Retained on
#60
Medium and
Coarse Sand
Retained on
#200
Fine Sand
Passing #200
Silts and Clays
10
57
11
14
8
8
72
23
55
9
8
12
62
10
13
46
13
29
(continued)
-------
TABLE 2 (continued).
HARBOR: Marinette - Menominee, Wisconsin and Michigan
SAMPLED: November 5, 1975
Sieve No.
and
Description
Retained on
#10
Medium Gravel
and Larger
ro
o
01 Retained on
#20
Fine Gravel
Retained on
#60
Medium and
Coarse Sand
Retained on
#200
Fine Sand
Sediment Size Analysis by Percent at Each Station
MAR 75-5 MAR 75-5 MAR 75-5 MAR 75-6 MAR 75-7 MAR 75-8 MAR 75-9 MAR 75-10
split replicate replicate
split
6 10 11 5 8 4 4 4
8 5826372
56 71 66 20 12 33 74 73
8 13 12 10 23 19 4 7
Passing #200
Silts and Clays
22
63
51
41
11
14
-------
o
o>
TABLE 3. BULK SEDIMENT ANALYSES AT MARINETTE-MENOMINEE HARBOR
HARBOR: Marinette - Menominee, Wisconsin and Michigan
SAMPLED: November 5, 1975
Parameter
Total Solids %
Volatile Solids %
Chem. Oxy Demand
T. Kjel Nitrogen
Oil-Grease
Mercury
Lead
Zinc
T. Phosphorus
Ammonia Nitrogen
Manganese
Nickel
Arsenic
Cadmium
Chromium
Magnesium
Copper
Iron
MAR 75-1
75.3
<1.00
11,000
310
<250
<0. 1
<10
25
150
20
180
<8
<2
<2
6
5,200
6
61,000
MAR 75-2
32.0
14.4
200,000
5,400
3,100
0.2
74
190
1,200
390
880
26
87
9
31
18,500
50
17,000
MAR 75-3
73.2
1.95
12,000
330
300
0.1
<10
34
180
18
220
<8
3
<2
6
6,900
9
5,900
MAR 75-4
67.4
1.91
21,000
620
500
<0. 1
35
40
210
33
300
<8
10
<2
8
7,500
13
6,200
MAR 75-5
69.4
2.64
20,000
360
<250
<0. 1
<10
30
190
23
220
<8
5
<2
7
6,600
7
6,200
MAR 75-5
split
69.6
2.06
21,000
470
<250
<0. 1
<10
30
170
23
200
<8
5
<2
7
4,900
7
7,300
MAR 75-5
repl icate
69.7
2.73
20,000
540
400
<0. 1
13
30
190
21
170
<8
5
<2
6
3,700
7
6,500
MAR 75-5
replicate-
split
73.7
2.10
32,000
1,100
300
<0. 1
14
26
240
30
160
<8
5
<2
7
3,800
6
7,000
All values mg/kg dry weight unless otherwise noted.
(continued)
-------
TABLE 3 (continued).
HARBOR: Marinette - Menominee, Wisconsin and Michigan
SAMPLES: November 5, 1975
ro
o
Parameter
Total Solids %
Volatile Solids %
Chem. Oxy. Demand
T. Kjel. Nitrogen
Oil -Grease
Mercury
Lead
Zinc
T. Phosphorus
Ammonia Nitrogen
Manganese
Nickel
Arsenic
Cadmium
Chromium
Magnesium
Copper
Iron
MAR 75-6
53.4
12.1
83,000
1,800
900
<0.1
24
67
420
100
380
12
14
<2
11
10,800
19
9,200
MAR 75-7
58.9
3.60
51,000
1,000
500
<0.1
22
52
310
53
330
12
7
<2
9
13,900
14
7,700
MAR 75-8
62.9
3.10
36,000
890
400
<0.1
20
44
280
46
310
12
6
<2
6
16,300
9
6,900
MAR 75-9
74.1
<1.00
3,500
66
<250
<0.1
<10
17
150
<10
130
<8
3
<2
6
2,500
3
5,700
MAR 75-10
71.2
1.04
4,900
130
<250
<0. 1
<10
23
150
24
150
<8
3
<2
4
7,100
8
3,700
All values mg/kg dry weight unless otherwise noted.
-------
ro
o
oo
TABLE 4. MACROINVERTEBRATE ANALYSIS FROM MARINETTE-MENOMINEE HARBOR
HARBOR: Marinette - Menominee, Wisconsin and Michigan
SAMPLED: November 5, 1975
Taxa
Diptera
Chirononrus sp.
Dubiyaphia sp.
D-iopotend-ipes sp.
Procladius sp.
Oligochaeta
Lirmodri-lus sp.
Tubifetc sp.
Ephemeroptera
Hexagenia limbata
Isopoda
Ascellus sp.
Amphipoda
Gammarus fasaiatus
Total No. of organisms
Total No. of taxa
Number of Organisms for
MAR 75-1 MAR 75-2 MAR 75-4
7
1
11
1 10
5
1 1
1 1 35
1 1 6
Each Taxa
Mar 75-6
7
3
6
2
1
•
2
4
25
7
MAR 75-7
1
6
1
8
3
-------
U. S. Environmental Protection Agency requested that the U. S. Army Corps of
Engineers suspend all dredging plans for the harbor until levels of PCBs in
the channel sediments could be determined.
In May, 1976, the Great Lakes Surveillance Branch of the U. S. Environ-
mental Protection Agency obtained seven sediment samples within the federal
navigation channel. Eight additional samples were collected with the harbor
area (Figure 2).
Total PCB concentrations ranged .from 0.1 mg/kg near the opening of the
harbor to 4200 mg/kg at the north end of the harbor (Table 5, Figure 2). Sedi-
ments near the source of past discharges in the north section of the harbor are
heavily contaminated. Field observations of these sediments indicated they
were gray-black in color with a strong petroleum odor. Sediments near the
opening to the harbor consisted of fine to medium sand. Material in this
vicinity consists of littoral drift sands which move north to south along the
shore.
It was recommended that sediments lakeward of the South Pier are suitable
for open lake disposal. Sediments within the harbor upstream of this location
require confined disposal. Sediments at the north end of the inner basin will
require special dredging operations when removed to reduce turbidity and over-
flow to minimize contact between water and severely contaminated sediments.
REFERENCES
I. Michigan Water Resources Commission, Polychlorinated Biphenyls in the
Saginaw River System. Unpublished Report (1972).
2. Hesse, John L. , Polychlorinated Biphenyl Usage and Sources of Loss to
the Environment in Michigan. In: National Conference on Polychlorinated
Biphenyls (November 19-21, 1975, Chicago, Illinois). EPA-560/6-75-004
(1976).
3. Michigan Water Resources Commission, Water Quality and Pollution Control
in Michigan (305 b Report). (April 1976).
209
-------
OUTBOARD MARINE CORP
JOHNSON L,
MOTOR CO. C
CITY FILT. PL.
SOUTH PIER
O.I
88C
I
_, MILWAUKEE
WISCONSIN
RACINE
87°
I l
LAKE
MICHIGAN
VICINITY MAP
10 0 10 20 30 40
2^SZ!S
SCALE IN MILES
IEW
1UFFAIC
...ICHIGAN
CITY
43° A0B SAMPLE SITE - JUNE 9,1976
A. SAMPLE SITE - MAY 12,1976
6
A = Sample site number
B= Total PCB's in mg/kg dry weight
42°
Figure 2.. Sampling stations at Waukegan Harbor.
210
-------
ro
TABLE 5. POLYCHLORINATED BIPHENYL CONCENTRATIONS AT WAUKEGAN HABOR
HARBOR: Waukegen, Illinois
SAMPLED: May 12, 1976
Station
Number
1
2
2 split
2 replicate
2 replicate/split
3
4
4 split
4 replicate
4 replicate/split
5
6
7
Percent
Moisture
50.5
50.4
54.1
57.3
53.3
24.0
32.1
33.2
25.5
28.4
21.4
17.9
16.8
1242
16
6.7
5.4
5.2
4.9
0.7
NF
0.6
0.5
1.0
0.3
NF
NF
Aroclors
1248
20
5.8
5.9
5.4
6.0
1.1
3.7
2.4
1.3
1.3
1.1
0.2
0.1
1016 Total PCB
36
12.5
11.3
10.6
10.9
1.8
3.7
3.0
1.8
2.3
1.4
0.2
0.1
All values in mg/kg (ppm) dry weight.
(continued)
-------
TABLE 5 (continued).
HARBOR: Waukegan, Illinois
SAMPLED: June 9, 1976
Station
Number
1
2
ro
3
4
5
6
7
8
Percent
Moisture
19.9
31.1
33.9
56.3
50.7
48.6
55.4
35.0
Aroclors
1242 1248
2600
1200
32
68
61
73
120
8.3
1016
1300
3000
42
180
240
59
98
2.8
Total PCB
3900
4200
74
248
301
132
218
11.1
All values in mg/kg (ppm) dry weight.
NF: None found. This indicates that the PCB level was below the detection limit of 0.1 mg/kg.
-------
IMPACTS ASSOCIATED WITH THE DISCHARGE
OF DREDGED MATERIAL INTO OPEN WATER
R. M. Engler
U. S. Army Engineer Waterways Experiment Station
Environmental Effects Laboratory
Vicksburg, Mississippi 39180
ABSTRACT
With few exceptions, impacts of aquatic disposal
are mainly associated with the physical effects. These
possible effects are persistent, often irreversible,
and compounding. Geochemically, releases are limited
to nutrients with negligible release of toxic metals
and hydrocarbons. Biochemical interactions are infre-
quent with no clear trends and elevated uptake of toxic
metals and hydrocarbons are negligible to nonexistant.
INTRODUCTION
Navigable waterways of the United States have, through the years, played
a vital role in the nation's economic growth. The Corps of Engineers (CE), in
fulfilling its mission to maintain, improve, and extend these waterways, is
responsible for the dredging and disposal of large volumes of sediment each
year. Dredging is a process by which sediments are removed from the bottom of
streams, rivers, lakes, and coastal waters; transported via ship, barge, or
pipeline; and discharged to land or water. Annual quantities of dredged
material currently average about 300,000,000 cubic yards (186,000,000 dry tons)
in maintenance dredged operations and about 80,000,000 cubic yards (48,000,000
dry tons) in new work dredging operations with the total annual cost now
exceeding $150,000,000 (1).
In recent years, as sediments in many waterways and harbors have become
contaminated, concern has developed that dredging and disposal of this material
may adversely affect water quality or aquatic organisms. A number of localized
studies have been made to investigate the environmental impact of specific
disposal practices and to explore alternative disposal methods. However, these
studies have not provided sufficient definitive information on the environ-
mental impact of current disposal practices, nor have they fully investigated
alternative disposal methods. As a result, the CE was authorized by Congress
in the 1970 River and Harbor Act to initiate a comprehensive nationwide study
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to provide more definitive information on the environmental impact of dredging
and dredged material disposal operations and to develop new or improved dredged
material disposal practices. The U. S. Army Engineer Waterways Experiment
Station (WES) was assigned the responsibility of developing and managing a
comprehensive multidisciplinary five-year multimillion dollar research program
known as the Dredged Material Research Program (DMRP). A more detailed plan-
ning, technical and management structure can be found in references 2 and 3.
The DMRP is subdivided into four projects. The Environmental Impacts and
Criteria Development Project (EICDP) will be discussed in this paper. The
EICDP is further divided into six general task areas that are generally de-
scribed by their respective titles. These tasks are: 1A - Aquatic Disposal
Field Investigations; IB - Movements of Dredged Material; 1C - Effects of
Dredging and Disposal on Water Quality; ID - Effects of Dredging and Disposal
on Aquatic Organisms; 2D Confined Disposal Area Effluent and Leachate Control;
and IE Pollution Status of Dredged Material.
Task 1A includes major field investigations where field application of
laboratory findings of the numerous biological, chemical, and physical investi-
gations of open water disposal are underway. This task involves hopper dredged
and barge disposal in freshwater, estuarine, and marine locations. Pipeline
discharge investigations are being conducted as a part of Task IB and IE.
The development of mathematical models to predict dispersion and final
fate of dredged material comprise the general objectives of Task IB.
Tasks 1C and ID are involved with determining the effects of open-water
disposal on water quality and aquatic organisms through laboratory investiga-
tions. Specifically, Task 1C is concerned with the mobilization and immobil-
ization of chemical constituents during open-water disposal and longer term
release after the material has settled to the bottom. Task ID is concerned
with the biological uptake and utilization of chemical constituents and the
longer term physical and chemical effects of aquatic organisms through labora-
tory evaluations.
Task 2D involves the characterization of contaminant mobility within and
from upland dredged material containment areas and the effects on the surround-
ing ecosystem.
Task IE involves the previous listed investigations and combines their
results with additional investigations to develop more meaningful and imple-
mentable regulatory criteria.
Fundamental to understanding the impact of sediment discharge and resus-
pension on water quality is an understanding of how chemical constituents,
which may have various effects on aquatic organisms, are associated with
dredged sediments.
Sediments may be separated into several components or phases which are
classified by their composition and mode of transport to the estuarine environ-
ment. Among them are detrital and authigenic phases.
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Detrital components are those which have been transported to a particular
area usually by water. Detrital materials are derived from soils of the sur-
rounding watershed and can include (a) mineral grains and rock fragments (soil
particles) as well as stable aggregates, (b) associated organic material, and
(c) culturally contributed components derived from agricultural runoff and
industrial and municipal waste discharges.
Authigenic components are those which are formed in place or have not
undergone appreciable transport. These materials are generally the results of
aquatic organisms and include (a) shell material (CaC03), (b) diatom frustules
(Si02), (c) some organic compounds, and (d) products of anaerobic or aerobic
transformations.
In considering the J_n situ association with various sediment phases of
trace elements in estuarine sediments, the water contained in inter-particle
voids or interstices must be considered. This is termed interstitial water
(IW). In relation to the overlying water, chemical constituents may frequently
be enriched in the IW by several mechanisms. Some constituents (metals and
some nutrients) are ionically bound to the sediment in several exchange loca-
tions. These include the exchange sites of the silicate phase and exchange
sites associated with organic matter or trace elements complexed with the
organic phase. Heavy metals are also associated with hydrated manganese and
iron oxides and hydroxides which are present in varying amounts in the sedi-
ment. Another location for heavy metals is in the sediment organic phase.
The metals are incorporated into living terrestrial and aquatic organisms and
are relatively stable but may be released into the sediment-water system during
decomposition. The greatest concentration of chemical constituents, however,
is contained in the silicate mineral fraction (earth's crustal material) of a
sediment.
From the previous discussion of elemental partitioning and for analytical
purposes, the following categories of sediment components will be considered.
a. Interstitial water (IW). This water, an integral part of sediment,
is in dynamic equilibrium with the silicate and organic exchange phases of the
sediment as well as with the easily decomposable organic phase.
b. Mineral exchange phase. That portion of the element that can be
removed from the cation exchange sites of the sediment using a standard ion-
exchange extractant (NH4OAc, dilute HC1, Mad, MgCl2, etc).
c. Reducible phase. This phase is composed of hydrous oxides of iron
and manganese as well as hydroxides of Fe and Mn, which are relatively
reducing (anaerobic) conditions. Of particular importance are the toxic metals
(An, Cu, Cd, Ni, Co, and Hg) that may be associated with these discrete Fe or
Mn phases as occlusions or coprecipitates.
d. Organic phase. This phase or partition of elements is that consider-
ed to be solubilized after destruction of the organic matter. This phase
contains very tightly bound elements as well as those loosely chelated by or-
ganic molecules. An initial extraction by an organic chelate may be needed to
differentiate between the loosely bound and tightly bound elements.
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e. Residual phase. This phase contains primary minerals as well as
secondary weathered minerals which are for the most part a very stable portion
of the elemental constituents. Only an extremely harsh acid digestion or
fusion will break down this phase. By far the largest concentration of metals
is normally found in this fraction.
A particular element or molecule can be present (be partitioned) in a
sediment in one or more of several locations. The possible locations include:
(a) the lattice of crystalline minerals, (b) the interlayer position of
phyllosilicate (clay) minerals, (c) adsorbed on mineral surfaces, (d)
associated with hydrous iron and manganese oxides are hydroxides which can
exist as surface coatings or discrete particles, (e) absorbed or adsorbed with
organic matter which can exist as surface coatings or discrete particles, and
(f) dissolved in the sediment interstitial water. These locations also repre-
sent a range in the degree by which an element may become dissolved in the
receiving water. This range extends from stable components in the mineral
lattices, which are essentially insoluble, to soluble compounds dissolved in
the sediment interstitial water, which are readily mobile. Electrochemical
(Eh, pH) changes after disturbing and resuspending anaerobic bottom sediments
may result in possible solution or precipitation of many elemental species
and should be thoroughly characterized.
A sediment characterization procedure to elucidate the phase distribution
of contaminants in dredged material must be applicable to many types of marine
and freshwater sediments, both aerobic and anaerobic. To be realistic, sedi-
ment disturbance must be minimal. Thus, drying, grinding, and contact with
atmospheric oxygen is undesirable. Such a technique has been developed and
subjected to preliminary evaluation (4). The sediment phases previously listed
here are shown in their relative order of mobility and bioavailability, inter-
stitial water being most mobile and consequently most available. When a con-
taminant enters a body of water it normally enters two or three factions in
varying concentrations but cannot be distinguished from natural levels by a
bulk or total analysis. An example of the distribution of iron in a sediment
from Mobile Bay, Alabama (5), has concentrations in the interstitial water
(0.23% of total), exchangeable (2.13% of total), reducible (76.4% of total),
organic (12.6% of total), and residual (8.55% of total). The total sediment
iron concentration is 31,100 mg per kg of sediment. Iron is shown to be
widely distributed throughout the sediment phases with the interstitial water
containing the least, the exchangeable phase containing a small fraction, and
the moderately reducible phase containing the largest concentration of iron in
the sediment. Under aerobic conditions the iron would be immobile or fixed in
the sediment. Copper distribution in this sediment is as follows: intersti-
tial water (0.0032% of total), exchangeable (none detected), reducible (6.35%
of total), organic (32.63% of total), and residual (61.2% of total). Total
copper concentration is 37.8 mg per Kg sediment. This residual phase, which
contains the largest fraction of sediment copper, can only come in the solution
during geologic weathering processes and has no acute or chronic biological
impact. The organic phase may go through various transformations and a frac-
tion of the organic portion could be rendered mobile. However, movement would
be slow and solution copper would be rapidly diluted to ambient levels. These
results only hint at the complexity of chemical constituent distribution within
216
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and among sediments; for a detailed discussion of sediment chemistry and water
quality interrelations the reader is referred to references 5 and 6.
Results of the Task 1C, laboratory investigations of the impact of dis-
posal of water quality, show that ammonium, manganese, iron and ortho-
phosphate were released from anaerobic sediments during disposal and initial
mixing and after the sediment has settled to the bottom (7, 8). It was found,
however, that the sediments scavenged or cleaned the water column of numerous
toxic heavy metals and nutrients when contaminated fine-grained harbor sedi-
ments were dispersed in a water column. No release of chlorinated hydro-
carbons was detected (7, 9) during the simulated open-water disposal of dredged
material from a broad selection of marine, freshwater, and estuarine sediments.
After the sediments had settled and formed a new sediment-water interface,
several constituent release and immobilization patterns were detected
(7, 8, 9). Release from the sediments to the water column, with the exception
of iron, manganese, and some nutrients, was extremely small. Several toxic
heavy metals were released in concentrations less than one part per billion
levels from either contaminated harbor sediments or noncontaminated sediments.
It must be emphasized that these processes and transformations occur naturally
in all sediments at similar levels (7, 8) and do not appear to be of a pollu-
tional nature.
Further studies of chemical constituent release mechanisms (10) have
evaluated conditions that enhance release of toxic metals when the sediment-
water geochemical environment is drastically changed. As an example, the
significant release of zinc to the water soluble phase was shown to occur at
pH 5 under oxidizing (Eh) conditions. It must be emphasized that these acid-
oxidizing, pH-Eh conditions do not normally occur in open-water disposal as
anaerobic sediments normally remain near neutral pH and the oxidization
processes that occur in the water column are not such as to result in an acidic
condition (10). Subsequently, after the sediment settles it normally returns
to an anaerobic and near neutral pH condition. On the other hand, if this
sediment is placed in an upland containment area where oxidizing conditions can
occur for a year or more and the sediments are high in total sulfide (common in
many fine-grained estuarine sediments), the pH can become acidic and result in
significant release of some contaminants (10) to the water soluble phase.
Therefore, judicious selection of the disposal mode (open-water versus upland)
and an understanding of the long-term implications of either disposal mode is
very important. These previous observations and numerous other geochemical
transformations of an extensive list of sediment constituents are discussed in
detail in references 7, 8, 9, and 10.
The previously reported research has suggested little release of most
chemical constituents from dredged material, further emphasizing the need for
determining the biological effect of chemicals associated with the sediment
solid fraction. The physical effect, irrespective of chemical nature of this
fraction, on various organisms must also be thoroughly evaluated. Investiga-
tions underway in Task ID are determining the effects of turbidity (suspended
dredged material) on aquatic organisms, the uptake of sediment sorbed metals
and pesticides, the ability of organisms to migrate vertically through deposits
of dredged material, and the biological effects of sediment contained oil and
grease.
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Turbidity studies (11), conducted with marine, estuarine, and freshwater
organisms have shown lethal concentrations of suspended dredged material to be
significantly (an order of magnitude or more) higher than those concentrations
observed in the field. In these laboratory studies the mortality of select
organisms were demonstrated in concentrations of suspensions of dredged
material exceeding 2-20 grams per liter (2,000 - 20,000 ppm) at 21-day exposure
times. Field observations have shown turbidity or suspended particulate levels
to be less than 1 gram per liter (1,000 ppm) for exposure times of only hours.
Based on these and other observations, it was concluded that the physical
effect of turbidity from dredged material discharge in open-water would have
minimal biological impact. Consequently, the primary impact of turbidity is
of an aesthetic nature and must be controlled and treated as such. The only
exception to this would be the sensitive coral reefs of Florida and Hawaii
where low concentrations of suspended particulate can significantly impact
large areas. Additional studies are currently underway to evaluate the uptake
of contaminants from the suspended dredged material by aquatic organisms
(benthic and water column) and will be completed later this year.
Other physical impact investigations underway in Task ID are evaluating
the ability of estuarine and freshwater benthic organisms to recover vertically
after being covered or smothered by various loadings of dredged material (12).
These laboratory evaluations are being conducted by the University of Delaware,
Lewes, Delaware, and have demonstrated that select organisms (clams, crabs, and
benthic worms) have been able to recover through as much as a meter covering
or have been smothered by as little as a few centimeters covering of different
types of dredged material. The organisms generally recovered through the
deposits in a matter of hours, and minutes in some cases. These studies are
investigating combinations of sand dredged material deposited on mud and mud
dredged material on sand substrates. The most drastic biological impact was
noted when unlike materials were placed on each other. Especially where a
sand dredged material was placed on a mud substrate and covered normally mud
dwelling organisms that were not suited for mobility through the sand or where
sand dwelling organisms were quickly smothered by a mud covering. Judicious
selection of disposal site where sand is placed on a sand bottom or mud on
a mud bottom is imperative to minimize immediate or long-term physical impact
at the site. Field studies in this task demonstrated that benthic organism
recolonization (13) of dredged material mounds formed during disposal was
relatively rapid and the processes were attributed in some part to vertical
migration. However, a significant number of organisms also may be brought out
with the dredged material and affect recolonization patterns.
Toxic heavy metal uptake studies (14) are a significant part of Task ID
and involve biological assessment of estuarine and freshwater shrimp, clams,
and benthic worms grown in contaminated sediments from the Houston Ship Channel,
the Ashtabula River (Ohio), and other locations. The Houston Ship Channel
sediments, highly contaminated with toxic heavy metals and chlorinated hydro-
carbons, were generally toxic to a number of the organisms studied but were
chosen a worst case material. This dredged material is not disposed in open-
water but confined in a land containment area. The organisms that lived through
the experiments, however, did not appear to take up any toxic heavy metals.
They did, however, take up significant quantities of iron and manganese which
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have very limited, if any, toxological properties. Zinc was the only other
metal to show an accumulation trend. The uptake results could not be corre-
lated to sediment bulk or total constituent concentrations. Freshwater studies
with Ashtabula River sediments demonstrated that when freshwater worms from a
clean environment were placed on the Ashtabula sediments, metals generally were
taken up by these organisms. Uptake, however, reached concentrations exhibited
in organisms that normally live in these sediments and did not exceed this
level, and when the animals were transferred to clean sediments, they returned
to their original or initial body burden. This study is nearing completion
and will contribute significantly to the knowledge of metal uptake from
contaminated sediments and its relation to aquatic disposal of dredged mate-
rial. Pesticide uptake studies (15) have shown that maximum utilization by
benthic organisms was from the interstitial water and minimum uptake from the
solid sediment fraction. Perhaps, covering pesticide contaminated sediments
with "clean" material at a disposal site will mitigate the organism utiliza-
tion by isolating the contaminated material from the active benthic community
that lives at or slightly below the sediment-water interface.
Task IE investigations for the development of meaningful and implementable
regulatory criteria for Public Laws 92-500 and 92-532 and other EICDP studies
have shown conclusively that no relationship exists between "bulk" or "total
sediment analysis" sediment characteristics and the effect of aquatic disposal
on water quality or aquatic organisms (4, 5, 6, 7, 8, 9, 10, 15, 17, 18).
These investigations have, however, shown that the "elutriate test" (19, 20)
can be used to predict water quality perturbations and water column biological
impacts (5, 6, 16, 17, 18). Further development and implementation of dredged
material regulatory criteria have resulted in publication of "Interim Guidance"
(20) for Section 404(b)l of Public Law 92-500 pursuant to the 5 September 1977
Federal Register (21). This document, recently published and released by the
WES, includes "cookbook" procedures and interpretive guidance for the Federal
Register (21) and discusses procedures to be used for an ecological evaluation
of the discharge of dredged and fill material in inland waters. The testing
procedures include sediment analyses, water column evaluations, elutriate
tests, water column bioassay, mixing zone estimations, and other physical and
biological evaluations. Development of a benthic bioassay is currently a
DMRP priority at WES, and under contract. It is envisioned that a benthic
bioassay will be developed within the next twelve to twenty-four months.
Field verification of the required regulatory procedures is underway at this
time at numerous marine and freshwater locations (22) and will complement the
completed laboratory research.
Large scale field investigations of the short- and long-term physical,
chemical, and biological impacts of open-water disposal are completed in Long
Island Sound, Lake Erie near Ashtabula, Ohio, the Gulf of Mexico near Galveston,
Texas, Puget Sound off Seattle, Washington, and in the Pacific Ocean off the
mouth of the Columbia River (23, 24). Chemical water-column effects duplicate
the laboratory investigations previously reported in this paper, where only low
levels of some nutrients and the metals iron and manganese were apparently
released. Turbidity or suspended particulate was found in concentrations
significantly (an order of magnitude or more) lower than concentrations shown
to have an impact on a broad range of aquatic organisms (11) and persisted
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only for a few hours. Significant impacts noted in these studies were the
mounding of dredged material on the bottom of the dump sites. Biological
recolonization studies of these mounds are incomplete at this time. However,
there is initial evidence of rapid biological recolonization of some of the
disposal areas. Sediment chemistry at the sites have shown elevated concentra-
tions of chemical constituents in the sediment interstitial water at the dis-
posal site as well as the control or reference areas. Movement or release of
these chemical constituents out of the sediments of the disposal or reference
sites was not apparent.
Studies are complete where organisms at select sites are being analyzed
for metals or chlorinated hydrocarbon uptake. Initial evidence from the Eatons
Neck disposal site in Long Island Sound, Ashtabula in Lake Erie, and in Puget
Sound off the Duwamish Waterway has shown no increased uptake of numerous toxic
and nontoxic heavy metals and chlorinated hyc,ocarbons by several organisms
when compared with control or reference areas. These field studies were
completed in December 1976 and the final results, conclusions and recommenda-
tions are in publication (24). Petroleum hydrocarbon uptake studies (25) have
shown minimal uptake from highly contaminated sediments.
CONCLUSIONS
1. The field evaluations are verifying results demonstrated in the laboratory
investigations.
2. Water column impact during disposal appears minimal to nonexistent and
effect is predominately aesthetic in nature.
3. Leaching of toxic heavy metals from the disposal mound into the water
column appears no greater than from natural sediments of similar geologic
character. Chlorinated hydrocarbon release was not detected. Nutrients
were released to small concentrations greater than background.
4. The major bottom impact found at disposal sites was the physical mounding
of the material. Benthic recolonization of the mounds appears relatively
rapid.
5. "Bulk" or total sediment analysis does not relate to any mobile or bio-
available fraction of a sediment nor can it predict or evaluate water
quality and ecological perturbations.
6. Water quality criteria and bioassays have been developed for Public Law
92-500 and 92-532 and are being field verified at this time.
7. Toxic heavy metal uptake studies are incomplete but initial trends suggest
minimal to no impact in marine and estuarine sediments.
8. Petroleum and chlorinated hydrocarbon uptake studies are complete at this
time, and initial trends suggest minimal uptake from solid phase of sedi-
ments.
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REFERENCES
1. Boyd, M. B. , R. T. Saucier, J. W. Keeley, R. L. Montgomery, R. D. Brown,
D. B. Mathis, and C. J. Buide. Disposal of Dredge Spoil; Problem Identi-
fication and Assessment and Research Program Development. Technical
Report H-72-8. U. S. Army Engineer Waterways Experiment Station,
Vicksburg, Mississippi, 1972.
2. U. S. Army Engineer Waterways Experiment Station. First Annual Report -
Dredged Material Research Program. Vicksburg, Mississippi, 1974.
3. U. S. Army Engineer Waterways Experiment Station. Second Annual Report -
Dredged Material Research Program. Vicksburg, Mississippi, 1975.
4. Engler, R. M., J. M. Brannon, J. Rose, and G. Bigham. A Practical Selec-
tive Extraction Procedure for Sediment Characterization. Proc. Symp. on
Chemistry of Marine Sediments. Amer. Chem. Soc. Natl. Meeting, Atlantic
City, New Jersey, September 1974.
5. Brannon, J. M. , I. Smith, J. Rose, R. M. Engler, and P. G. Hunt.
Investigation of Partitioning of Various Elements in Dredged Material.
Technical Report (in preparation, DMRP Work Unit 1E04), L). S. Army
Engineer Waterways Experiment Station, Vicksburg, Mississippi.
6. Brannon, J. R. , R. M. Engler, J. Rose, P. G. Hunt. Distribution of
Manganese, Nickel, Zinc, Cadmium and Arsenic in Sediments and in the
Standard Elutriate. Miscellaneous Paper D-76-18. U. S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi, 1976.
7. Chen, K. Y. , S. K. Gupta, A. Z. Sycip, J. C. S. Lee, M. Knezevic, and
W. W. Choi. The Effect of Dispersion, Settling and Resedimentation on
Migration of Chemical Constituents During Open Water Disposal of Dredged
Material. Contract Report D-76-1. U. S. Army Engineer Waterways Experi-
ment Station, Vicksburg, Mississippi, 1976.
8. Blom, B. E. , T. F- Jenkins, D. C. Leggett, and R. P. Murrmann. Effect of
Sediment Organic Matter on Migration of Various Chemical Constituents
During Disposal of Dredged Material. Contract Report D-76-7. U. S. Army
Engineer Waterways Experiment Station, Vicksburg, Mississippi, 1976.
9. Fulk, R. , D. Gruber, and R. Wullechleger. Laboratory Study of the
Release of Pesticide and PCB Materials to the Water Column During
Dredging and Disposal Operations. Contract Report D-75-6. U. S. Army
Engineer Waterways Experiment Station, Vicksburg, Mississippi, 1975.
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10. Grabrell, R. P., R. A. Khalid, M. G. Verloo, and W. H. Patrick, Jr.
Transformations of Heavy Metals and Plant Nutrients in Dredged Sediment
as Affected by Oxidation-Reductions Potential and pH. Contract Report
D-77-4. U. S. Army Engineer Waterways Experiment Station, Vicksburg,
Mississippi, May 1977.
11. Peddicord, R. K. , and V. McFarland. Response of Selected Aquatic
Organisms to Suspended Dredged Material. Contract Report (in prepara-
tion, DMRP Work Unit 1D09). U. S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississipp, 1977.
12. Kech, R. Determination of the Vertical Migration Ability of Benthos in
Dredged Material Deposits. Interim Report, DMRP Work Unit 1D03. U. S.
Army Engineer Waterways Experiment Station, Vicksburg, Mississippi, 1975.
13. Oliver, J. S. , P. N. Slattery, L. W. Hulenburg, and J. W. Nybakken.
Patterns of Succession in Benthic Infaunal Communities Following Dredging
and Dredged Material Disposal in Monteray Bay. Contract Report (in
preparation, DMRP Work Unit 1D10). U. S. Army Engineer Waterways Experi-
ment Station, Vicksburg, Mississippi, 1977.
14. Slowey, J. F., J. W. Neff, and J. W. Anderson. Study of the Availability
of Sediment-Sorbed Heavy Metals to Benthos with Particular Emphasis on
Deposit-Feeding Fauna. Contract Report (in preparation, DMRP Work Unit
1D06. U. S. Army Engineer Waterways Experiment Station, Vicksburg,
Mississippi, 1977.
15. Nathans, M. W. , and T. J. Bechtel. Study to Determine the Availability
of Sediment-Sorbed Selected Pesticides to Benthos with Particular Emphasis
on Deposit Feeding Infauna. Contract Report (in publication, DMRP Work
Unit 1D07). U. S. Army Engineer Waterways Experiment Station, Vicksburg,
Mississippi, 1976.
16. Lee, G. F , and R. H. Plumb. Literature Review on Research Study for the
Development of Dredged Material Criteria. Contract Report D-74-1. U. S.
Army Engineer Waterways Experiment Station, Vicksburg, Mississippi, 1974.
17. Lee, G. F. , M. D. Piwoni, J. M. Lopez, G. M. Mariani, J. S. Richardson,
D. H. Homer, and F. Saleh. Research Study for the Development of Dredged
Material Disposal Criteria. Contract Report D-75-4. U. S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi, 1975.
18. Shuba, P. J. , and J. H. Carroll. Biological Assessment of Soluble
Fraction of the Dredged Material Elutriate Test. Technical Report (in
preparation, DMRP Work Unit 1E06). U. S. Army Engineer Waterways Experi-
ment Station, Vicksburg, Mississippi, 1976.
19. Keeley, J. W. , and R. M. Engler. Discussion of Regulatory Criteria for
Ocean Disposal of Dredged Materials: Elutriate Test Rationale and Imple-
mentation Guidelines. Miscellaneous Paper D-74-14. U. S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi, 1974.
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20. Engler, R. M. , et al. Ecological Evaluation of Proposed Discharge of
Dredged or Fill Material into Navigable Waters - Interim Guidance for
Implementation to Section 404(b)(1) of Public Law 92-500. Miscellaneous
Paper D-76-17. U. S. Army Engineer Waterways Experiment Station,
Vicksburg, Mississippi, 1976.
21. Federal Register, Vol. 40, No. 173, Friday, 5 September 1975.
22. Lee, G. F. Refinement of Current Disposal Criteria, Identification of
Subject Areas for Further Development and Refinement of Bioassay Pro-
cedures for Disposal Criteria. Contract Report (in preparation, DMRP
Work Unit 1E03A). U. S. Army Engineer Waterways Experiment Station,
Vicksburg, Mississippi, 1976.
23. U. S. Army Engineer Waterways Experiment Station. Third Annual Report
Dredged Material Research Program. Vicksburg, Mississippi, 1976.
24. U. S. Army Engineer Waterways Experiment Station. Fourth Annual Report -
Dredged Material Research Program. Vicksburg, Mississippi, 1977.
25. Disalvo, L. H. , H. E. Guard, N. D. Hirsh, and J. Ng. Assessment and
Significance of Sediment Associated Oil and Grease in Aquatic Environ-
ments. Technical Report D-77-26. U. S. Army Engineer Waterways Experi-
ment Station, Vicksburg, Mississippi, 1977.
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A BIOASSAY FOR THE TOXICITY OF SEDIMENT TO THE MARINE MACROBENTHOS
R. C. Swartz, W. A. DeBen, and F- A. Cole
U. S. Environmental Protection Agency
Corvallis Environmental Research Laboratory
Newport, Oregon 97365
ABSTRACT
A bioassay has been developed to determine the acute
toxicity of the settleable phase of dredged material to
the marine benthos. Five benthic invertebrates repre-
senting different taxonomic and trophic positions were
allowed to acclimate to control (non-polluted) sediment
and were then covered by a layer of either test or con-
trol sediment. Mean survival after ten days of exposure
was significantly different from the controls for sedi-
ment from the Duwamish River, Wa; Houston Ship Channel,
Tx; Bailey Creek, Va; and Raritan River, NJ: but there
was no significant difference for sediment from Coos Bay
and the Skipanon River, Or. There were substantial dif-
ferences in survival among the five test species. The
most sensitive species was the infaunal amphipod,
Paraphoxus epistomus.
INTRODUCTION
The final Revision of Ocean Dumping Regulations and Criteria published by
the Environmental Protection Agency1 requires, under certain conditions, bio-
assays of the liquid, suspended, and solid phases of sediments proposed for
dredging and disposal in the marine environment. Procedures for these bio-
assays were recently published by the Corps of Engineers2. Results of experi-
ments which contributed to the development of the bioassay for the solid or
settleable phase of dredged material are presented in this report.
Our objective was to develop a test, for the acute toxicity of the settle-
able components. The bioassay was designed not to be sensitive to burial or
changes in sediment particle size distribution. Such effects can certainly
disrupt benthic communities within dump site boundaries, but are unavoidable
even during the disposal of unpolluted sediment. We were interested in meas-
uring the toxicity of dredged solids whose disposal might result in the trophic
or physical transport of pollutants beyond the dump site.
The bioassay technique roughly simulates the dumping of dredged material
into the sea. Five macrobenthic invertebrates representing different taxon-
225
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omic and trophic positions were selected as the test species because of the
vulnerability of the benthos to the settleable portion of dredged sediments.
These organisms were allowed to acclimate to control (non-polluted) sediment
and were then covered in different replicates by a layer of either test or
control sediment. Except during the one hour period of initial settling, the
bioassay aquaria were supplied with a continuous flow of seawater which carried
away the dissolved and suspended phases. Survival relative to controls after
ten days of exposure was the primary response criterion.
Bioassays were conducted for sediments from the Atlantic, Gulf of Mexico,
and Pacific coasts of the United States. The collection sites were chosen to
provide a comparison of the toxicity of sediments which had been exposed to a
variety of kinds and degrees of pollution.
MATERIALS AND METHODS
SEDIMENT SAMPLES
Benthic bioassays were performed on sediments from Yaquina Bay, Coos Bay
(4 stations) and the Skipanon River, Oregon; the Duwamish River (3 stations),
Elliott Bay, and Puget Sound, Washington; Houston Ship Channel, Texas (5
stations); Bailey Creek, Virginia; and the Raritan River, New Jersey (Table 1).
There are no significant sources of pollution in the vicinity of the Yaquina
Bay collection site. The four Coos Bay stations are in a channel next to a
number of log loading docks. The Skipanon River station is adjacent to a fish-
ing marina. Bailey Creek is near the site of the kepone contaminations of the
James River. The Duwamish, Raritan, and Houston Channel systems are exposed to
a variety of industrial and domestic sources of pollution. Slip No. 1 in the
Duwamish was the site of a PCB spill on 13 September 1974. The benthic bio-
assay sediment sample from slip No. 1 was collected after two attempts had been
made to clean up the PCB contamination3. The Elliott Bay station is located at
an experimental dump site for Duwamish River sediments4. Houston Channel sta-
tions II, III, IV, and V are near a chlor-alkali plant, pulp and paper mill,
oil refinery, and sewage outfall, respectively. Station I is off Morgan's
Point at the entrance to the channel.
The sediment samples were maintained at 4°C from the time of collection
until the initiation of the bioassay, a period that did not exceed two weeks.
The samples were either sieved through a 0.5 mm screen or frozen to remove
macrofaunal specimens. Sediment particle size distribution was determined for
the sand fraction by use of a Wentworth screen series and for the silt-clay
fraction by the pipette method5.
TEST SPECIES
Test specimens were collected with a bottom dredge from Yaquina Bay,
Oregon and removed from the sediment by sieving through a 1.0 mm screen. The
five species used in each experiment included the pelecypods, Protothaca
staminea and Macoma inquinata; the polychaete, Glycinde pi eta; and the emphi-
pod, Paraphoxus epistomus. The fifth species was one of the following cum-
226
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TABLE 1. SOURCE AND PARTICLE SIZE DISTRIBUTION OF SEDIMENT USED IN BENTHIC BIOASSAYS
ro
ro
Sediment Si
Experiment Sediment Type
Number
1
2
3
4
Yaquina Bay Control
Yaquina Bay Control
Fraction of Control:
Silt
Very Fine Sand
Fine Sand
Medium Sand
Coarse Quartz Sand
Very Coarse Quartz Sand
Control Fractions - Quartz
Sand Composite
Yaquina Bay Control
Duwamish River Turning Basin
Duwamish River Slip No. 1
Duwamish River Mouth
Elliott Bay
Puget Sound
Yaquina Bay Control
Coos Bay Station I
Coos Bay Station II
Coos Bay Station III
Coos Bay Station IV
%Sand
98.
98.
3.
87.
100.
100.
100.
100.
86.
98.
24.
14.
29.
39.
11.
99.
98.
66.
94.
96.
7
6
7
0
0
0
0
0
3
9
2
6
7
0
4
0
7
8
3
0
%Silt
0.
0.
93.
9.
13.
0.
64.
60.
57.
51.
45.
0.
0.
25.
3.
2.
3
5
6
8
0
3
3
4
5
0
2
3
4
7
3
1
ze Distribution
%Clay
1.
0.
2.
3.
0.
0.
11.
25.
12.
10.
43.
0.
0.
7.
2.
1.
0
9
7
2
7
8
5
0
8
0
7
7
9
5
4
9
Mean Grain
Size (|j)
209
204
26
69
188
272
859
1395
259
202
21
12
26
21
7
203
289
62
193
203
Collection Site
44°37I39I1N,124°02
47°3T07"N,122°18
47°33124"N,122°20
47035'12"N,122°21
47035'41"N,122°21
47035'45"N,122°23
43°22129"N,124°12
43023'03"N,124°13
43°23'53"N)124°12
43°24'42"N,124012
'30"W
'18"W
'31"W
'32"W
'42"W
•58"W
'25"W
'04"W
'49"W
'59"W
(continued)
-------
Table 1 (continued).
ro
ro
oo
Sediment Si
Experiment Sediment Type
Number
5
6
7
8
Yaquina Bay Control
Houston Ship Channel Station I
Houston Ship Channel Station II
Houston Ship Channel Station III
Houston Ship Channel Station IV
Houston Ship Channel Station V
Yaquina Bay Control
Bailey Creek
Yaquina Bay Control
Skipanon River
Yaquina Bay Control
Raritan River
%Sand
98.7
5.2
2.6
11.2
31.0
40.3
96.5
41.9
98.4
6.2
99.1
23.1
%Silt
0.5
48.0
38.6
28.5
58.7
38.1
1.8
31.5
0.6
68.8
0.2
38.4
ze Distribution
Mean Grain
%Clay Size (M)
0.8
46.8
58.9
50.3
20.3
21.6
1.7
26.5
1.0
25.0
0.7
38.5
196
6
4
7
19
29
187
29
200
11
212
16
Collection Site
29040'41"N,94°58I12"W
29044'30"N,95°06128"W
29043130"N,95012'50"W
29°43'24"N,95013'59"W
29045'00"N,95017120"W
37°17119"N)77015'27"W
46010'15"N,123°54I45"W
40°29'40"N,74015'24"W
-------
aceans: Diastylis alaskensis, Lamprops quadriplicata, Diastylopis dawsoni, or
Cyclaspis sp. , depending upon availability in Yaquina Bay at the time of each
experiment. These species represent different feeding types and taxocenes which
often dominate continental shelf and estuarine benthic assemblages.
Since the test organisms occurred naturally at the Yaquina Bay sediment
collection site, that sediment was used as a control against which the toxicity
of sediments from other areas was compared.
BIOASSAY PROCEDURE
The bioassay aquaria were polyethylene boxes (Fusion-Rubbermaid*, No.
1315) with an approximately 25 1 capacity and 1200 cm2 bottom area (Figure 1).
They were supplied with a continuous flow of seawater (0.5 1/min) at ambient
temperature and salinity (9.5 - 16.8°C, 23.5 - 32.7 °/00 during the experiment
series).
Eight experiments were conducted from May 1976 until April 1977. The basic
design was to place a 28 mm layer of control sediment on the bottom of each
aquarium. Test organisms were randomly distributed so that each tank contained
20 individuals of each of the 5 species. They were allowed to "acclimate" for a
48 hr period during which dead or lethargic specimens were replaced. Treatments
were randomly assigned to the aquaria after the acclimation period. The test
sediment was then introduced by distributing it evenly over the water surface
and allowing it to settle for 1 hr while the seawater was turned off. After 1 hr
the normal flow resumed and the dissolved and suspended fractions were flushed
out. The solid or settleable fraction remained as an even layer on top of the
control sediment. After 10 days surviving individuals were recovered by sieving
the sediment through a 0.7 mm screen and counted.
STATISTICAL ANALYSIS
Differences in mean survival between the control and test sediments were
compared for the individual species and the entire assemblage. Dunnett's
procedure6 for comparing more than one mean with a control was used for experi-
ments 1, 3/4, and 5. Student's "t" was used for experiments 6, 7, and 8 which
involved only one experimental treatment. Since the objective was to determine
if survival was less than in the control, one-tailed Student and Dunnett "t"
tables were used to determine significant, differences.
RESULTS
EFFECTS OF BURIAL
The first experiment was designed to determine the effects of burial by
Yaquina Bay sediment. Sediment layers of 5, 10, 15, 20, 25, and 30 mm thickness -
*Mention of trade names does not imply endorsement by the Environmental Pro-
tection Agency.
229
-------
ro
co
o
FLOW RATE
0.5 l/min.
O
WATER DEPTH = 15cm
/////////
.,,,,
.'!i////i'{
Figure 1. Diagram of the benthic bioassay aquarium.
-------
es were deposited on top of the 28 mm bottom sediment layer. A seventh
treatment consisted of a non-burial control, i.e. an overlying layer was not
deposited. Replicate bioassays were conducted for each sediment depth and
the non-burial control.
Mean survival in the non-burial control for each individual species and
for the entire assemblage was not significantly different from survival at any
of the burial depths (Table 2). With one exception, the number of survivors
in individual aquaria ranged from 89 to 97 specimens (x = 93.5). An outlier
(81 survivors) occurred in one of the 20 mm burial treatments. In the two
replicates buried under 15 mm of sediment, 91 and 94 of the initial 100 speci-
mens were recovered. This was considered to be a sufficiently low control
mortality for routine toxicity bioassays. After the first experiment only one
sediment depth (15 mm) was deposited on top of the bottom layer containing the
test organisms. Thus, the control replicates received 15 mm of Yaquina sedi-
ment on top of 28 mm of Yaquina sediment. The experimental replicates received
15 mm of test sediment on top of 28 mm of Yaquina sediment.
EFFECTS OF CHANGES IN SEDIMENT PARTICLE SIZE
The second experiment examined the effects of different particle size
distributions. The eight treatments were not replicated. They included
Yaquina sediment fractions with mean grain sized of 26, 69, 188, and 272u;
coarse (859u) and very coarse (1359u) quartz sands obtained from an aquarium
supply company; a composite of the six preceding sediments (259|j); and intact
sediment (204fj).
Obvious effects of particle size alterations were found only for the
survival of cumaceans in the coarse and very coarse sand fractions (Table 3).
Mean recovery for the entire assemblage on the sediment fractions with mean
grain sizes between 26 and 272u was 89.5 individuals. Within this group, the
unsieved control sediment had the lowest recovery (85 individuals). The mean
particle size of sediments used in later experiments ranged from 4 - 289u.
Further evidence that fine grain sediments did not affect survival was obtained
in the bioassay of Skipanon River sediment which had llu mean grain size, but
no significant difference from the control in the survival of any species or
the entire assemblage.
SEDIMENT TOXICITY BIOASSAYS
The last six experiments involved bioassays of sediment from various
coastal regions of the United States. All treatments in the first three
toxicity bioassays were replicated twice. Sediments collected along a tran-
sect from the Turning Basin, Slip No. 1, and mouth of the Duwamish River, and
from adjacent Elliott Bay and Puget Sound were used in the third experiment.
The fourth and fifth experiments included sediment from four stations in Coos
Bay and five stations in the Houston Ship Channel, respectively. There were
five replicates of the Yaquina control and the test sediment in the last three
experiments. Test sediment from one station in Bailey Creek, Skipanon River,
and Raritan River were used in the sixth, seventh, and eighth experiments,
respectively.
231
-------
ro
CO
ro
TABLE 2. SURVIVAL OF A MACROBENTHIC ASSEMBLAGE TEN DAYS AFTER DECOMPOSITION
OF YAQUINA BAY (CONTROL) SEDIMENT LAYERS 0-30 mm IN THICKNESS.
Mean Number Recovered
Sediment Layer (mm)
Species
Protothaca staminea
Macoma inquinata
Glycinde pi eta
Paraphoxus epistomus
Cumacea
Initial
Number
20
20
20
20
20
Non-burial
Control
0
20.0
20.0
17.5
18.5
19.0
5
20.0
20.0
17.0
19.5
19.0
10
19.5
19.5
18.0
17.5
18.0
15
20.0
20.0
18.5
17.5
16.5
20
18.0
18.5
17.5
18.0
17.0
25
19.5
19.5
1G.5
18.0
18.5
30
19.0
20.0
17.5
19.5
15.5
TOTAL
100
95.0
95.5
92.5
92.5
89.0
92.0
91.5
-------
GO
CO
TABLE 3. EFFECTS OF CHANGES IN SEDIMENT PARTICLE SIZE DISTRIBUTION ON THE SURVIVAL OF THE MACROBENTHIC
ASSEMBLAGE. MEAN GRAIN SIZE (m) OF THE SEDIMENT TYPES IS GIVEN IN PARENTHESES
Number Recovered
Species
Protothaca staminea
Macoma inquinata
Glycinde pi eta
Paraphoxus epistomus
Cumacea
TOTAL
Initial
Number
20
20
20
20
20
100
Yaquina
Silt
(26)
20
18
17
15
19
89
Yaquina
Very Fine
Sand
(69)
20
19
19
18
15
91
Yaquina
Fine
Sand
(188)
20
18
19
15
19
91
Yaquina
Medium
Sand
(272)
20
20
16
18
14
88
Quartz
Coarse
Sand
(859)
20
20
19
13
4
76
Quartz
Very Coarse
Sand
(1395)
20
20
20
15
7
82
Composite*
(259)
20
20
20
14
19
93
Yaquina
Control
(204)
20
18
17
16
14
85
^Composite of equal volume of all test sediments except the intact Yaquina control.
-------
There were no significant differences from the controls in the mean sur-
vival of any species exposed to sediment from the Skipanon River (Expt. 7) or
any of the four Coos Bay stations (Expt. 4)(Table 4).
The differences between mean survival of total individuals in the controls
and in sediment from the Raritan River (Expt. 8), Bailey Creek (Expt. 6), and
the five stations in the Houston Ship Channel (Expt. 5) were all highly signif-
icant (Table 4). The impact of these sediments was most obvious in the survival
of Paraphoxus epistomus and the cumacea. The mean survival of Glycinde picta
in the Houston Channel stations III and V replicates and the mean for Mocoma
inquinata in the Bailey Creek sediment were also significantly different. The
Houston Channel station III sediment was the most toxic of any tested in the
bioassay experiments. Within the two replicates for that station, only 9 of
the initial 80 amphipods and cumaceans survived the 10 day exposure period,
while 77 survived in the controls.
There was evidence of spatial differences in the toxicity of sediment
along the Duwamish River-Puget Sound transect (Expt. 3, Table 4). Lowest total
survival was observed for sediment from the Turning Basin and Slip No. 1. The
differences from the control were highly significant for both of these stations
and for the Elliott Bay dump site. Mean total survival was not significantly
different for Duwamish River mouth sediment. It was significantly different
for Puget Sound station, although none of the individual species means differed
significantly from the controls.
Mean survival of cumaceans was not significantly less than the control for
any of the Duwamish River, Elliott Bay, or Puget Sound sediments (Expt. 3,
Table 4). However only between 2 and 13 (x = 8.6) cumaceans survived in the
individual aquaria. The range of cumacean survival for the Yaquina Bay con-
trols in all experiments was 14 - 20 (x - 17.5). Because these ranges do not
overlap, we suspect that sediment along this transect may be toxic to cumaceans
even though the means based on two replicates were not statistically different
from the experiment 3 control.
The sediment toxicity experiments revealed obvious interspecific differ-
ences in sensitivity. Protothaca staminea was not affected by any of the test
sediments. The survival of both Glycinde picta and Macoma inquinata was sig-
nificantly less than the control in only two instances and crustaceans were
always more sensitive than the polychaete or molluscs. The statistical signif-
icance of the difference between mean survival of Paraphoxus epistomus in the
control and test replicates was the same as that of the entire assemblage in
16 of the 17 bioassays.
DISCUSSION
The solid phase of sediments from the Duwamish and Raritan Rivers, Bailey
Creek, and Houston Ship Channel retained sufficient toxicity to cause the acute
mortality of benthic invertebrates. If such sediments were introduced in large
quantities into the sea, the dump sites could become significant sources of
marine pollution. The ultimate ecological impact of polluted sediment disposal
can only be determined through field or laboratory studies of chronically ex-
234
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TABLE 4. MEAN SURVIVAL OF THE MACROBENTHIC ASSEMBLAGE IN SEDIMENT TOXICITY BIOASSAYS
(Twenty individuals of each species were initially placed in each replicate.)
ro
CO
en
Mean Survival
Experiment
Number
3
4
5
6
7
8
Number
Total Protothaca
Sediment Type of Replicates
Yaquina Control
Duwamish Turning Basin
Duwamish Slip No. 1
Duwamish Mouth
Elliott Bay
Puget Sound
Yaquina Control
Coos Bay Station I
Coos Bay Station II
Coos Bay Station III
Coos Bay Station IV
Yaquina Control
Houston Channel Station I
Houston Channel Station II
Houston Channel Station III
Houston Channel Station IV
Houston Channel Station V
Yaquina Control
Bailey Creek
Yaquina Control
Skipanon River
Yaquina Control
Raritan River
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
5
5
5
5
5
5
87.5
69.0**
65.0**
81.5
71.0**
76.0*
94.0
91.0
92.0
93.0
94.5
98.0
80.0**
85.0**
58.5**
75.0**
77.0**
96.6
81.2**
91.8
90.0
93.8
79.6**
staminea
19.5
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
19.5
20.0
19.5
18.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
20.0
Macoma
Inquinata
19.5
17.0
13.0*
16.0
17.5
16.5
18.5
19.5
19.5
19.5
19.5
20.0
20.0
20.0
20.0
20.0
20.0
20.0
17.0*
20.0
19.4
19.8
19.2
Glycinde
pi eta
14.0
17.5
16.0
17.0
15.5
14.0
19.5
20.0
18.0
18.5
19.0
20.0
20.0
20.0
16.0**
19.5
17.0**
18.4
17.6
17.2
19.6
16.8
17.0
Paraphoxus
epi stomus
19.5
4.0**
9.0**
17.0
12.0
17.5
19.0
18.5
18.5
18.5
18.0
20.0
13.5*
13.5*
0.5**
6.0**
7.0**
18.2
12.2**
18.4
16.6
18.8
g 4**
Cumacea
14.0
10.5
7.0
11.5
6.0
8.0
17.0
13.0
16.0
16.5
18.0
18.5
6.5**
12.0*
4.0**
9.5**
13.0
20.0
14.4**
16.2
14.4
18.4
14.0**
- -
*P<0.05
**P<0.01
-------
posed biological communities. However, the type of short term bioassay de-
scribed here can provide data useful in the regulation of dumping activities.
The selection of appropriately sensitive benthic species is essential to
the success of this bioassay in a regulatory program. The Implementation
Manual published by the Corps of Engineers2 recommends that the five test
species be selected from the natural dominants of benthic assemblages in the
vicinity of the dump site. Because of the response of Paraphoxus epistomus in
our experiments, the Manual identifies infaunal amphipods as especially approp-
riate. The other test species must represent different taxonomic and trophic
groups. If sublethal phenomena such as bioaccumulation are to be examined, it
would be desirable to include species like Protothaca staminea which can be
expected to survive the exposure period.
Laboratory cultures exist for relatively few benthic species. Our exper-
ience has shown that with reasonable care it is possible to collect test organ-
isms from wild populations and maintain them under control conditions with low
mortality. Since a variety of test spucies will be used in different coastal
regions, the Implementation Manual suggests that a mysid shrimp of the genus
Mysidopsis or Neomysis be included for inter-bioassay comparisons. These my-
sids can be maintained in continuous culture7' 8.
The test assemblage used in our experiments showed little, if any, sensi-
tivity to burial under 15 mm of sediment or to alterations in grain size dis-
tribution. This is undoubtedly not true for all benthic organisms. The effects
of these factors must be determined before other species are used in the bio-
assay.
The Ocean Dumping Regulations state that dredged material may be dumped
only when the discharge will not exceed the "limiting permissible concentra-
tion" (LPC), i.e. that concentration which will not cause unreasonable toxi-
city. It is difficult to apply the LPC concept to the solid phase either in
the water column or sediment after it has settled to the bottom. The Impele-
mentation Manual concludes that the results of the benthic bioassay provide an
operational determination of the LPC. If mean survival in the test sediment
is at least 10 percent less than the control mean and if the difference is sig-
nificant at the 0.05 probability level, the LPC would by definition be exceeded.
The percent differences between means which were statistically significant in
our experiments ranged from 13.1 to 40.3 percent for the entire assemblage and
from 15.0 to 97.5 percent for individual species.
The benthic bioassay has other applications in pollution control. Test
sediment could be collected from sewage and dredge material dump sites, ocean
outfalls or other benthic habitats suspected of being contaminated. The bio-
assay could indicate causal relationships between sediment toxicity and alter-
ations in benthic community structure. Many regulatory programs emphasize
water quality criteria, but less attention has been paid to sediment quality
criteria9. Safe sediment concentrations for specific pollutants could be esti-
mated through acute or chronic benthic bioassays. Chemical monitoring could
then determine if the sediment criteria are exceeded.
236
-------
ACKNOWLEDGMENTS
Credits. We thank Lon Bentsen for conducting the sediment particle size
analyses. Drs. Robert Olson, Richard Caldwell, and Donald Baumgartner kindly
reviewed the manuscript.
REFERENCES
1. Environmental Protection Agency. 1977. Ocean dumping - Final Revision
of Regulations and Criteria. Federal Register 42:2462-2490.
2. Environmental Protection Agency/Corps of Engineers Tech. Comm. on Criteria
for Dredged and Fill Material. 1977. Ecological evaluation of proposed
discharge of dredged material into ocean waters. Implementation Manual
for Sec. 103 of P.L. 92-532. App. F: Guidance for performing solid phase
bioassays. U. S. Army Engineer Waterways Experiment Station, Vicksburg,
Mississippi.
3. Willmann, J. C. 1977. PCB transformer spill Seattle, Washington. J.
Hazardous Materials 1 (1975/77):361-372.
4. Baumgartner, D. J. , D. W. Schults, S. E. Ingle, and D. T. Specht. 1977.
Interchange of nutrients and metals between sediments and water during
dredged material disposal in coastal waters. J.n Peterson, S. A. and K. K.
Randolph (eds). Management of bottom sediments containing toxic sub-
stances. EPA Ecological Research Series 600/3-77-083, p. 229-245.
5. Buchanan, J. B. and J. M. Kain. 1971. Measurement of physical and chem-
ical environment. Jji Holme, N. A. and A. D. Mclntyre (eds.). Methods for
the study of marine benthos. IBP Handbook NO. 16, p. 30-51.
6. Steel, R. G. D. , and J. H. Torrie. 1960. Principles and procedures of
statistics. McGraw-Hill Book Co. , Inc. 481 p.
7. Nimmo,. D. R. , L. H. Banner, R. A. Rigby, J. M. Sheppard and A. J. Wilson,
Jr. 1977. Mysidopsis bahia: an estuarine species suitable for life-
cycle toxicity tests to determine the effects of a pollutant. I_n Mayer,
F. L. and J. L. Hamelink (eds.). Aquatic toxicology and hazard evalua-
tion, ASTM STP 634. American Soc. Testing and Materials, p. 109-116.
8. Nimmo, D. R. , R. A. Rigby, L. H. Banner and J. M. Sheppard. 1977. The
acute and chronic effects of cadmium on the estuarine mysid, Mysidopsis
bahia. Bull. Environ. Contam. andToxicol. 19(1). In press.
9. National Academy of Sciences - National Academy of Engineers. 1973.
Water quality criteria 1972 - A report of the committee on water quality
criteria. EPA Ecological Research Series R3-73-033. 549 p.
237
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EUTROPHICATION CONTROL:
IMPORTANCE OF INTERNAL PHOSPHORUS SUPPLIES
D. P. Larsen and D. W. Schults
Corvallis Environmental Research Laboratory
U.S. Environmental Protection Agency
Corvallis, Oregon 97330
ABSTRACT
Simple phosphorus mass balance models describing
the relationship between supplies of phosphorus to lakes
and resultant lake phosphorus concentrations demonstrate
that internal supplies of phosphorus could be important
in controlling lake concentrations. Recent investiga-
tions show that several areas within lakes could supply
significant amounts of phosphorus over short periods of
time. These include sediments overlain by anaerobic
water, macrophyte communities, and littoral zone sedi-
ments especially when stirred by wind-induced turbulence.
Chemical analyses of the phosphorus content of surficial
sediments show that the sediments act as a significant
phosphorus reservoir, but not all the sediment phos-
phorus is in a form readily exchangeable with overlying
waters. Chemical fractionation techniques have been
used to separate various phosphorus fractions in sedi-
ments. One fraction, denoted non-apatite inorganic
phosphorus (Williams et, al. , 1976a), is thought to
represent the sediment phosphorus which is potentially
most likely to release into overlying waters. It can
account for a large portion of the total phosphorus
content of some lake sediments. Examples describing the
importance of internal phosphorus supplies show that the
restoration of some lakes has been delayed by the feed-
back of phosphorus from the sediments at critical times
during the year.
INTRODUCTION
Recent syntheses of phosphorus and chlorophyll a data analyzed over a
broad spectrum of lakes demonstrate a significant correlation between the
mass or concentration of chlorophyll a (algal biomass) in the trophogenic
zone of lakes and the total phosphorus content of the same zone. Nicholls
239
-------
and Dillon (1977) summarized these relationships and showed significant
relationships between algal biomass (summertime) measured as average cell
volume and total phosphorus at springtime. The implication of these relation-
ships is that there is a close coupling between the phosphorus content of
lakes and the production of algae (see Rigler, 1975; Dillon and Rigler, 1974)
and that one way to reduce algal concentrations is to reduce the concentration
of phosphorus in lakes. This has been the major thrust of many lake restora-
tion projects. Thus an analysis of factors controlling phosphorus concentra-
tions in lakes is important.
The phosphorus content of lakes occurs as a balance between phosphorus
supplies to, and losses from, the lake and can be described conveniently as:
(Vollenweider, 1976; Sonzogni et a]_. , 1976)
— = J! + ^ - PW[P] - a[P] (1)
dt V V W P
where [P] is the average phosphorus concentration in the lake; V, the lake
volume; J and J , the supplies of phosphorus to the lake from external and
internal sources; and p and a , the fractional losses of lake phosphorus
through the outlet or to the lake Bottom.
The sensitivity of lake phosphorus concentrations to supply rates can be
easily demonstrated by the following simplification of Equation (1). For the
situation in which J = 0 (no internal supply of phosphorus), water inflow
and outflow are steady and equal, and lake volume is constant, the steady
state solution to Equation (1) can be written (Rigler, 1975):
[P] = ^e (1-R) (2)
Q
where Q is the water inflow rate and R the fraction of inflowing phosphorus
retained by the sediments. Assuming that R remains constant, any increase or
decrease in J will cause a corresponding change in phosphorus; doubling the
external supply of phosphorus will double the lake phosphorus content.
Increasing the supply of phosphorus to the lake from sediments is analagous
to increasing J without a corresponding increase in Q. This sensitivity of
lake phosphorus Concentrations to supply rates suggests that internal sources
could hypothetically be an important source of phosphorus.
This paper gives an overview of the importance of internal sources of
phosphorus in controlling lake phosphorus content, and thus in controlling
algal biomass within the lake. Included is a summary of the magnitude of
internal supply rates, nature of sources, and characteristics of sediments
which might relate to phosphorus release, as well as examples of lake restora-
tion experiments where the lake response has been delayed by internal supplies
of phosphorus.
240
-------
CONCEPTUAL MODEL
Figure 1 is a simplified conceptual model of the internal sources of
phosphorus within lakes. Three zones where release might occur include
hypolimnetic sediments, epilimnetic sediments, and regions where macrophytes
occur. Of these, the macrophyte zone and epilimnetic sediments have a direct
link to epilimnetic or euphotic zone waters, hence any release from these
regions can immediately stimulate an algal response if other growth factors
are not limiting. In contrast, transfer of phosphorus released from hypo-
limnetic sediments to the euphotic zone can be restricted by the thermocline.
Hence this phosphorus pool might not be so readily available except when
thermocline erosion occurs as caused by wind storms or cold front passage, or
by annual autumnal cooling and subsequent circulation.
General mechanisms by which phosphorus could be transported across the
sediment water interface include:
1) passive (molecular) diffusion: the mass phosphorus flux is depen-
dent upon the molecular diffusion coefficient for sediment pore waters
and the concentration gradient across the sediment water interface.
2) turbulent mixing: this mechanism could include transfer by physical
mixing of sediments (as generated by wind mixing, bottom currents, or
gas bubble movement), or by biological mixing (as from the movement of
demersal and benthic organisms).
3) biological transfer: transfer of phosphorus could occur as macro-
phytes absorb sediment phosphorus through root systems, releasing it
through leaves or as fish feeding upon benthic food excrete phosphorus.
Although not specifically a sediment source, it is worth mentioning that
the decomposition of settled macrophytes and phytoplankton, which have
not yet been assimilated into the sediments, can supply phosphorus to the
overlying waters and therefore tends to act as an internal supply of
biologically available phosphorus.
MAGNITUDES OF INTERNAL PHOSPHORUS SUPPLY RATES
Two general approaches have been adopted to quantify the flux of phospho-
rus across the sediment water interface: 1) j_n situ investigations and 2)
laboratory microcosm experiments. lr\ situ investigations have been of two
kinds. In one, portions of the lake bottom and overlying water are isolated
from the rest of the lake with chambers. Changes in phosphorus within the
chambers are measured over time and related to various properties of the
sediments and/or water. In the other, a phosphorus mass balance of the
entire lake is established. Changes in the phosphorus mass in the lake which
cannot be accounted for by external supplies and losses are attributed to
sediment interactions. Laboratory microcosm experiments are generally con-
ducted by removing sediments from the lake with varying degrees of disturbance
and incubating the sediments in chambers under controlled conditions in the
laboratory. Sediment release is measured as change in phosphorus content of
the overlying water over time. A general observation from these kinds of
241
-------
MACROPHYTE
ZONE
ro
ZONE
EPILIMNION
HYPOLIMNION
ITTORAL
PROFUNDAL
ZONE
Figure 1. Conceptual diagram of a lake showing various areas
where phosphorus can be released from sediments.
-------
experiments is that phosphorus tends to accumulate in sediments when overlying
waters are aerobic, but when anaerobic conditions develop, release occurs
(Mortimer, 1941, 1942, 1971). Release can occur under aerobic conditions,
but the rates are generally negligible. Tables 1 and 2 summarize phosphorus
release rates under anaerobic conditions for both j_n situ and laboratory
microcosm experiments. The range of release rates is broad, particularly for
the laboratory microcosm experiments. The shorter time period and the various
handling and "preparation" techniques associated with laboratory studies
might contribute to the broader range of results. The jji situ experiments
are more likely to provide an indication of long term (months) average phos-
phorus release from sediments. From this, more accurate estimates of average
phosphorus release rates could be computed.
A comparison of the anaerobic phosphorus release rates with annual
external phosphorus supplies expressed as a daily rate shows that internal
loading can be quite high relative to external loading (Table 1). The anaero-
bic release rates relate only to the area of lake bottom covered by anaerobic
water. To be comparable with external loadings the anaerobic release rates
should be normalized to lake surface area. For example, in Shagawa Lake,
Minnesota, the bottom area covered by anaerobic water is approximately 50% of
the lake area. Therefore the sediment release rate expressed over the lake
surface area would be 3.1 - 4.2 mg/m2/day instead of 6.2 - 8.3 mg/m2/day.
Even so, the release rates are high compared with external loadings (e.g. for
Shagawa Lake, the external loading was ~ 2 mg/m2/day prior to loading reduc-
tion).
Another way to demonstrate the importance of internal loading rates is
provided by the following example. If a sediment phosphorus release rate of
10 mg/m2/day is assumed and the overlying water column is 10 m thick, the
resultant increase in phosphorus concentration in the water column would be
about 1 mg/m3/day. This could translate into an increase in chlorophyll a^
content of 1 mg/m3/day. Vollenweider (1968) suggested loading rates in
excess of 0.20 mg/m2/yr might be regarded as critical for lakes of 10 m mean
depth. This is equivalent to about 0.5 mg/m2/day, about 20 times lower than
the above example of sediment release rates.
Experiments summarized in Tables 1 and 2 list the release of phosphorus
to overlying waters by mechanisms which are basically diffusional (molecular
or turbulent). These mechanisms are by far the most thoroughly investigated,
but generally their importance is greatest when anaerobic conditions occur.
Another mechanism, less thoroughly investigated but potentially as important,
is the transfer of phosphorus from littoral sediments through macrophyte
communities. Lie (1977) studied this phenomenon in Shagawa Lake. He isolated
areas of lake bottom dominated by macrophytes with plastic cylinders. He
measured the changes in phosphorus within the isolation chambers, insuring
that phosphorus was not transfered directly from the sediments by covering
them with plastic and/or sand. He measured fluxes of 12 - 116 mg/m2/day over
a nearly three-month period. These rates are significant but their importance
to the open lake water is difficult to assess because the amount of recycling
of phosphorus within the macrophyte zone is unknown. Also, in determining
the potential significance of macrophyte release, the areal distribution of
macrophytes should be considered. Macrophyte communities covered only about
2% of Shagawa's area.
243
-------
TABLE 1. PHOSPHORUS RELEASE RATES FROM SEDIMENTS ESTIMATED BY MASS
BALANCE TECHNIQUES OR BY USING CHAMBERS PLACED IN THE LAKE
External loading Release rate
Lake mg P/m2/day mg/m2/day
Baldeggersee
(Switzerland)
Erie (USA)
Mendota (USA)
Norrviken (Sweden)
Sammamish (USA)
Shagawa (USA)
9.5 (1958)
9.9 (1959)
3.5 7.4
10.8;7.2
11.1 1.6 - 9.2
(1961-1962)
1.3
(1975)
2.8 2.6 - 6.2
5.3
2.0 6.2 - 8.3
(1969-1972)
0.25
(1976)
Method Reference
mass balance Vollenweider (1968)
mass balance Vollenweider (1968)
mass balance Burns and Ross (1972)
mass balance Sonzongi (1974)
mass balance Ahlgren (1977)
in situ cylinders Welch (1977)
mass balance ' Welch (1977)
in situ chambers Sonzogni et al . (1976)
Larsen ejt al. (1978)
-------
TABLE 2. SEDIMENT PHOSPHORUS RELEASE RATES MEASURED IN
LABORATORY MICROCOSMS UNDER ANAEROBIC CONDITIONS
Phosphorus release
Lake
Warner (Massachusetts)
Fures0 (Denmark)
Esrom (Denmark)
Esrom (Denmark)
Grane Langs0 (Denmark)
St. Gribs0 (Denmark)
Bodensee
rate (mg/m2/day)
1.2
5.8
4.1
^3.3
0.3
0.4
0.65
Reference
Fillos and Swanson (1975)
Kamp-Nielsen (1974)
ii
Kamp-Nielsen (1975)
Kamp-Nielsen (1974)
ii
Banoub (1975)
(Germany, Switzerland)
White (Michigan) 34.2
Sodra Bergundasjb'n (Sweden) 34
Mohegan (New York) 1
Freedman and Canale (1977)
Bengtsson (1975)
Fillos and Biswas (1976)
Cooke et al. (1977) indirectly demonstrated the importance of the
littoral in supplying phosphorus in Twin Lakes, Ohio, by treating the hypolim-
nion with alum. They were able to reduce the hypolimnetic content of phospho-
rus significantly and demonstrated (using sediment oxygen demand chambers)
that phosphorus did not leak through the alum blanket in the anaerobic area
in the lake. However they observed an increase in epilimnetic phosphorus
comparable to that which had developed in the years prior to treatment. They
had hypothesized that the epilimnetic phosphorus increase occurred as a
result of anaerobic phosphorus release into the hypolimnion followed by
transfer into the epilimnion. Since they reduced the anaerobic phosphorus
release, yet observed increases in epilimnetic phosphorus, they concluded
that the littoral must be an important internal source of phosphorus.
Lee et al. (1977) suggest another mechanism which might be important in
controlling phosphorus release from the sediments. They measured phosphorus
release from sediments in water-filled glass carbuoys under conditions of
continuous turbulence keeping sediments in suspension. Although release
rates were highest when anaerobic conditions were imposed and release rates
were slow when aerobic conditions were imposed, significant amounts of P were
released over long periods of time (months) under aerobic conditions. The
significance of this mechanism in lakes has not.been investigated.
245
-------
Stauffer and Lee (1973) showed that a significant amount of phosphorus
could be mixed from the metalimnion or hypolimnion when turbulence was suffi-
cient to erode the thermocline. The effect of this sort of turbulence (high
intensity over short duration) can also have a significant effect by mixing
littoral sediments into overlying water (Lee, 1973). In Shagawa Lake, Larsen
et a!. (1978) calculated how much phosphorus might be transferred from the
stratified zone when the mixed zone deepened after windstorms (Table 3).
Phosphorus increases in the mixed zone after the windstorms were significantly
higher than expected from this transfer. They estimated that 500 - 900 kg of
phosphorus might have originated from the littoral when windstorms occurred
during the summers of 1974 and 1975. These releases were sufficient to
increase Shagawa Lake's average phosphorus content 10-15 mg/m3 within a few
days.
TABLE 3. SUMMARY OF TRANSFER OF PHOSPHORUS FROM STRATIFIED TO
MIXED ZONES IN SHAGAWA LAKE, MINNESOTA RESULTING FROM
THERMOCLINE EROSION, (from Larsen et al_. 1978)
Mixed Zone Stratified Zone
Observed Expected Observed Expected
Date Change Change Change Change
(kg) (kg)
1974
7/23-7/30
1975
7/20-8/5
8/5-8/12
8/12-8/19
+2030
+200
+1180
+550
+1110
+280
+540
+40
-1190
-120
-630
-50
-1110
-280
-540
-40
These examples demonstrate that the sediments can provide significant
amounts of phosphorus to overlying waters when appropriate conditions occur.
The following section describes some of the characteristics of sediments
relating to their potential as a reservoir of phosphorus.
LAKE SEDIMENT PHOSPHORUS CONTENT
The phosphorus content of material sedimented to lake bottoms generally
ranges from about 1 to 6 mg/g dry sediment (Table 4). Although surface
sediments contain 90 - 95% water (by weight), the amount of phosphorus in the
upper 10 cm is sizable. For sediments whose water content is 95% (by weight),
246
-------
TABLE 4. TOTAL PHOSPHORUS CONTENT OF SEDIMENTS
IN SELECTED LAKES IN NORTH AMERICA
Lake
Sammamish
Lower St. Regis
Huron
Ontario
Erie
Monona
Washington
Shagawa
Total phosphorus
(mg/g dry wt)
2 - 5
0.5 - 1.4
.1 -.2
•x.1.2 - ^3.0
0.19 - 2.9
•ul - ^2.2
^1 - >6
1 - 5
Core depth
40 cm core
35 cm core
50 cm core
50 cm core
50 cm core
top 3 cm
from 48 sites
100 cm core
40 cm core
160 cm core
Reference
Welch (1977)
Fuhs et al .
(1977)
Kemp et al .
(1972)
Kemp et al .
(1972)
Kemp et al .
(1972)
Williams et al .
(1976b)
Bortleson and
Lee (1975)
Shapiro et al .
(1971)
Bradbury and
Waddington
(1973)
TABLE 5. PHOSPHORUS CONCENTRATIONS IN PORE WATERS OF VARIOUS LAKES
Lake
Dissolved
Phosphorus
(mg/1 )
Reference
Sodra Bergundasjb'n
(Sweden)
White
(Michigan)
Ontario
(U.S.A., Canada)
Kinneret
(Israel)
Shagawa
(Minnesota)
1.16
2 - 5.5
0.055 - 1.04
0.01 - 0.069
up to ^4.5
Bengtsson (1975)
Freedman and
Canale (1977)
Bannermann e_t al_
(1974)
Serruya ejt al.
(1974)
Schults
(unpublished)
247
-------
whose sediment specific gravity is 2.5 g/cc and phosphorus content is 2 mg/g
(dry weight) ~10 g of phosphorus occur in an area of 1 m2 to a depth of 10
cm. If diluted in a water column 10 m deep, the resultant water column
phosphorus concentration would be about 1 mg/1. As a comparison, this is
equivalent to about 20% of the phosphorus concentration of municipal waste-
w'ater which has been subjected to secondary treatment. Although turbulence
sufficient to suspend 10 cm of sediments is unlikely, gradual mixing of the
sediments to depths greater than 10 cm often occurs (Lee, 1970) therefore
this zone might be considered potentially interactive with overlying waters.
Although a significant quantity of phosphorus is present in the surficial
sediments, not all is in a form which can readily interchange with lake
water. Th form most likely to exchange with lake waters is phosphorus dis-
solved in the pore water. Measurements of pore water phosphorus indicate
that concentrations are often as high as several mg/1 (Table 5), but this
amount is small compared with that in the solid phase. Because lake water
phosphorus concentrations are significantly lower than pore water concentra-
tions, gradients of dissolved phosphorus across the sediment water interface
can be quite high, providing a potential for significant transfer. For
example, dissolved reactive phosphorus gradients measured at the sediment
water interface in Shagawa Lake were ~1 /mg/1 /cm; release rates of 6 - 8 mg
P/m2/day have been measured under anaerobic conditions in submerged chambers
(Sonzogni et a!. , 1977). However, at these release rates, a reservoir of
dissolved phosphorus can be relatively quickly depleted: at a release rate
of 5 mg/m2/day, a pore water reservoir 10 cm deep whose phosphorus concentra-
tion is 1 mg/1 would be depleted within ~20 days. Thus, over the long run,
in order for continued release, this pore water phosphorus must be replenished
from particulate phosphorus.
Williams et al. (1976a) suggested that sediment phosphorus be opera-
tionally divided into 3 components based upon chemical extraction techniques.
These three components are "apatite phosphorus", "nonapatite inorganic phos-
phorus1' and "organic phosphorus". Organic phosphorus includes phosphorus
chemically bound to carbon directly or through oxygen, and is measured chem-
ically by methods described in Sommers et al. (1972). Apatite phosphorus is
phosphorus associated with the crystalline structure of apatite, and non-
apatite inorganic phosphorus consists of the remaining orthophosphate ions.
They are measured according to methods described in Williams and Mayer (1972).
This breakdown of phosphorus is similar to that used in describing the phos-
phorus content of terrestrial soils (Williams and Mayer, 1972). For terres-
trial soils, the non-apatite inorganic P (NAI-P) is thought to be the form
most readily available for root uptake and might be a valid measure of lake
sediment phosphorus available for macrophyte uptake. The NAI-P fraction is
also thought to be strongly associated with iron, perhaps as a "ferric oxide-
orthophosphate complex" under oxygenated conditions (Williams et aj. , 1972,
1976a). This complex dissociates under reducing conditions, releasing phos-
phorus into interstitial waters, and ultimately into the overlying waters.
Thus the amount of NAI-P present within the sediments might be a more valid
measure of the available sediment phosphorus reservoir than would be a measure
of total phosphorus or pore water phosphorus.
248
-------
Table 6 summarizes the sediment phosphorus fractions for several lakes.
In some cases, the fractions were determined in cores so that a vertical
distribution is available. These suggest that surface sediments deposited
since European settlement in the watershed are enriched with NAI-P relative
to sediments deposited prior to European settlement. One effect of European
settlement has been to increase the sediment reservoir of a form of phosphorus
most likely to exchange with overlying waters.
The magnitude of the NAI-P fractions in surficial lake sediments imply a
large reservoir of potentially available phosphorus. In Shagawa Lake about
75,000 kg occur in the upper 10 cm of the profundal zone sediments. The
significance of this reservoir can be seen when its magnitude is compared
with the amount of phosphorus supplied to the lake annually from wastewater
prior to treatment (~5000 kg) or to that estimated to be released from the
profundal zone sediments during July and August each year (1000 2000 kg)
(Larsen et al. , 1977). Shagawa Lake is in the process of recovering from
the effects of high supplies of phosphorus from wastewater as will be des-
cribed in the next section.
DELAYED RECOVERY CAUSED BY INTERNAL PHOSPHORUS LOADING
SHAGAWA LAKE
Discussion in the previous sections has shown that sediments can supply
significant amounts of phosphorus to lake waters and that there can be a
large reservoir of sediment phosphorus exchangeable with overlying waters.
The following section shows how these internal reservoirs have delayed the
restoration of some lakes.
Shagawa Lake is located in northeastern Minnesota in a forested watershed
whose lakes and tributaries are characterized by low nutrient concentrations
and whose lakes are characterized by low algal densities. Large blooms of
blue green algae (Apham'zomenon flos-aquae, Anabaena circinalis, and Anabaena
flos-aquae), high phosphorus and nitrogen concentrations, and anaerobic water
below six meters depth have characterized the lake for many years. The
stimulus for these conditions was attributed to the large supplies of nutri-
ents entering the lake from the city of Ely (population 5000), situated along
the lake's southern shore and discharging wastewater directly to the lake.
Wastewater discharge to the lake has occurred since at least 1911 when a
primary treatment plant was constructed. European settlement began to occur
about 25 years earlier, so that by 1911 the population had grown to ^3500
residents. By early 1973, a wastewater treatment plant was completed to
remove essentially all the wastewater phosphorus but to leave concentrations
of other elements unaltered as much as possible. The plant has operated
successfully for nearly five years, reducing wastewater total phosphorus
below 50 (jg/1 (Larsen et al_. , 1975, 1978; Malueg et al_. , 1975; Schults et
al. , 1976).
The hydraulic and morphometric characteristics of Shagawa suggest that
it should have responded immediately and rapidly to inflow phosphorus reduc-
tion (Table 7). It is a shallow lake (5.7 m mean depth) which is rapidly
249
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TABLE 6. PHOSPHORUS FRACTIONS IN SEDIMENTS OF VARIOUS LAKES IN NORTH AMERICA
ro
en
o
Lake
Erie (mean)
(range)
Total
phosphorus
0.879
0.188 - 2.863
(mg/g dry weight)
apatite non apatite
phosphorus inorganic phosphorus
0.445 0.330
0.144 - 2.277 0.038 - 2.329
organic
phosphorus Reference
0.110 Williams et al .
0 - 0.286 (1976b)
Ontario (range) 0.500 - 1.500 0.268 - 0.802 0.054 - 0.844
Shagawa (mean)
3.0
0.23
2.10
Wisconsin lakes
8 noncalcareous
lakes (range) 0.729 - 7.000 0.005 - 0.210 0.102 - 5.800
6 calcareous
lakes (range) 0.713 - 1.460 0.092 - 0.246 0.207 - 0.722
0 - 0.290 Bannerman et a^.
(1974)
Larsen et al. (1978)
(seven sites)
Williams et al.
(1971)
Williams et al.
(1972)
-------
TABLE 7. MORPHOMETRIC AND HYDROLOGIC CHARACTERISTICS
OF SHAGAWA LAKE, MINNESOTA
Maximum length:
Maximum width:
Maximum depth:
Mean depth:
Area:
Volume:
Altitude of lake
mean level:
Water residence time:
6.58 km
2.90 km
13.7 m
5.7 m
9.24 km2
53 x 106 m3
407.7 m
0.5 - 1.0 yr
TABLE 8. REDUCTION IN PHOSPHORUS SUPPLIES TO AND RESULTING
LAKE PHOSPHORUS REDUCTION IN SHAGAWA LAKE, MINNESOTA
(From Larsen e_t al_. 1978)
Year
Total phosphorus
supply
kg
Average influent
phosphorus
concentration
Average annual
lake phosphorus
concentration
yg/1
1971
1972
1973
1974
1975
1976
6800
6200
2100
1500
1000
900
71
100
20.6
17.8
15.3
20.8
47.4
54.1
48.7
31.4
29.3
29.5
251
-------
flushed by low phosphorus water from its tributaries, mainly Burntside River.
The water retention time ranges from ^0.5 - 1 yr and pretreatment phosphorus
retention time was less than 0.5 yr, suggesting a nearly complete response
within 1.5 - 2 yr after treatment.
Tertiary wastewater treatment for phosphorus removal has reduced the
external supply of phosphorus to the lake by nearly 80% (Table 8). The
average phosphorus concentration in the inflowing water (all external sources
combined) has been reduced from a range of 60 - 100 ug/1 during pretreatment
years to <20 ug/1. If internal supplies of phosphorus were negligible,
average lake phosphorus concentrations should be equal to or less than influ-
ent concentrations. Average lake total phosphorus concentrations have declined
from -v50 ug/1 pretreatment to -^30 ug/1 post treatment (annual averages),
values presently still higher than the average inflow concentrations.
The seasonal cycle of phosphorus concentrations in Shagawa Lake display
an important phenomenon which has apparently delayed its recovery (Figure 2).
Each summer lake phosphorus has increased 35 to 50 ug/1 from late June to
mid-August, an increase of 2000 - 3000 kg. This increase, equivalent to ~l/2
the 5000 - 5500 kg supplied annually by wastewater prior to treatment, cannot
be accounted for by the net import of phosphorus to the lake; the increase is
attributed to phosphorus discharge from lake sediments. A large part probably
originated from sediments overlain by anaerobic waters, but the littoral
might also be an important source especially during windstorms, or in areas
where macrophytes are dominant. There has been no appreciable change in the
amount of phosphorus discharged during these months in the years subsequent
to treatment.
Although the phosphorus content of the lake has declined significantly,
the response of the algal community has not been so noticeable (Table 9 and
Figure 3), particularly during the late summer. This can be explained by the
observation that during pretreatment years, phosphorus was present in excess
of algal requirements, hence algal biomass could have attained higher concen-
trations if not limited by other factors (Figure 4). The reservoir of soluble
reactive phosphorus present during pretreatment years is now nearly absent
implying that all the phosphorus supplied is consumed by algae and that
curtailment of the internal discharges would likely immediately reduce algal
concentrations.
LAKE NORRVIKEN, SWEDEN
Lake Norrviken, somewhat smaller than Shagawa Lake, had received both
industrial and municipal wastewater for many years. In June 1969, all the
wastewater was diverted from the lake, reducing not only phosphorus supplies
significantly, but also supplies of nitrogen and other elements. The lake
has a surface area of 2.7 km2, mean depth of 5.4 m, and a water retention
time of about 10 months (Table 10). It too should respond rapidly to phospho-
rus inflow reduction (Ahlgren, 1972; 1977).
During years prior to diversion, the total phosphorus supply to Lake
Norrviken has been ^4 g/m2/yr; diversion reduced this to M).5 g/m2/yr corres-
ponding to an influent phosphorus concentration of ~80 ug/1, an eight-fold
252
-------
TABLE 9. CHANGES IN AVERAGE TOTAL PHOSPHORUS AND CHLOROPHYLL a. IN
SHAGAWA LAKE, MINNESOTA, DURING THE ICE FREE SEASON
(approximately mid-May to mid-November). Numbers in
parentheses are ratios of the value for any particular
year to the mean of the 1971 and 1972 values.
(From Larsen e_t aj_. 1978)
Year
1971
1972
1973
1974
1975
1976
Total phosphorus
yg/1
54.5
(0.94)
60.9
(1.06)
50.8
(0.88)
35.7
(0.66)
34.6
(0.60)
35.7
(0.62)
Chlorophyll a
yg/1
20.0
(0.90)
24.3
(1.10)
21.2
(0.96)
11.3
(0.51)
16.3
(0.74)
18.5
(0.84)
TABLE 10. MORPHOMETRIC AND HYDROLOGIC CHARACTERISTICS
OF LAKE NORRVIKEN, SWEDEN (Ahlgren, 1977)
Surface area: 2.67 km2
Volume: 14.3 x 106 m3
Maximum depth: 12 m
Mean depth: 5.4 m
Drainage area: 91 km2
Water retention time: 10 months
253
-------
00
cr
o
Q_
o
X
Q_
_l
<
(-
O
80
60
40
20
0
*#$
A
M
0
N
Figure 2. Average total phosphorus concentrations in Shagawa Lake.
(from Larsen e£ al_. 1978)
254
-------
ro
tn
tn
60
a*
40
X
CL
O 20
or
O
o
0
A
'"•"•"•"•"•i
*"«"«"«"."«"F
\
•:•:•:•:•:•:* IQ~7O
*#•:•:•:•::• IJ f £.
\
I
I97I
'4
A ' M
A
0
N
Figure 3. Average chlorophyll ^concentrations in Shagawa Lake.
(from Larsen et al. 1978).
-------
40
ro
en
cr>
SOLUBLE REACTIVE PHOSPHORUS
PO GJ
0 0
0
1976
A
M
A
0
N
Figure 4. Average soluble reactive phosphorus concentrations in Shagawa Lake.
(from Larsen et a!. 1978)
-------
reduction in external phosphorus supply. Prior to diversion, the lake had
retained about 50% of the inflowing phosphorus in its sediments. If this
retention continued after treatment, an average lake concentration of MO
(jg/1 might be expected. Although this concentration has not been attained,
significant reduction in lake phosphorus has occurred, lake phosphorus concen-
trations declining from 470 pg/l at autumn overturn during 1969 to ^150 ug/1
at autumn overturn in 1975, and ~100 |jg/l during mid-1976.
Although during pretreatment years significant amounts of inflowing
phosphorus were annually sedimented to the lake bottom, subsequent to treat-
ment, there has generally been negligible retention of phosphorus by lake
sediments, suggesting that lake concentrations closer to influent concentra-
tions might be expected. In addition, significant discharge of phosphorus
from the sediments has occurred during May-August each year, but the rate of
discharge has declined significantly from -^9.2 mg/m2/day during 1971 to ^1.6
during 1976. This pattern of phosphorus discharge is surprisingly similar to
that observed in Shagawa Lake, except that in Norrviken, the internal supply
has been declining yearly. Whereas in the case of Shagawa Lake, markedly
lowered algal concentrations can be expected if sediment discharge is termin-
ated, in Norrviken, average phosphorus concentrations in the inflow are still
quite high (comparable to those for Shagawa Lake prior to phosphorus reduction)
so that continued blooms of noxious algae can be expected under phosphorus
controlled conditions.
SUMMARY
The supply of phosphorus from sources within a lake can be several times
the supplies from external sources for periods of time on the order of months.
These internal sources include sediments overlain by anaerobic waters and
littoral zone sediments stirred by turbulent activity or populated by macro-
phyte communities. Chemical measurements of sediment phosphorus content show
that the reservoir of total phosphorus within the sediments is high, but that
not all the phosphorus is in a chemical form which can exchange readily with
overlying waters. Even so, that fraction of sediment phosphorus most likely
to exchange with overlying waters can account for a large fraction of the
total phosphorus in the sediments. Two examples, the restoration of Shagawa
Lake, Minnesota, and Lake Norrviken, Sweden, show that the feedback of phos-
phorus from sediments can have a significant effect in delaying the recovery
of lakes whose external phosphorus supplies have been curtailed.
257
-------
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Ahlgren, I. Changes in Lake Norvviken After Sewage Diversion. Verb.
Internat. Verein. Limnol., 18: 355-361, 1972.
Ahlgren, I. Role of Sediments in the Process of Recovery of a Eutrophic
Lake. In: Proceedings of an International Symposium on Interactions
Between Sediments and Fresh Water, Amsterdam, Netherlands, September 6-
10, 1976, H.L. Golterman, ed. Dr. W. Junk B.V. Publishers, Hague, 1977.
pp 372-377.
Bannerman, R.T., D.E. Armstrong, G.C. Holdren, and R.F. Harris. Phosphorus
Mobility in Lake Ontario Sediments. Proc. 17th Conf. Great Lakes Res.,
1974. pp. 158-178.
Banoub, M.W. Experimental Studies on Material Transactions between Mud and
Water of the Gnadensee (Bodensee). Verh. Internat. Verein Limnol.,
19:1263-1271, 1975.
Bengtsson, L. Phosphorus Release from a Highly Eutrophic Lake Sediment.
Verh. Internat. Verein Limnol, 19:1107-1116, 1975.
Bortleson, J.C. and G.F- Lee. Recent Sedimentary History of Lake Monona,
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Bradbury, J.P., and J.C.B. Waddington. The Impact of European Settlement on
Shagawa Lake, Northeastern Minnesota. In: Quaternary Plant Ecology,
H.J.B. Birks and R.G. West, eds. Blackwells, Oxford, 1973. pp. 289-
307.
Burns, N.M. and Ross, C. Oxygen-Nutrient Relationships within the Central
Basin of Lake Erie. In: Project Hypo-An Intensive Study of the Lake
Erie Central Basin Hypolimnion and Related Surface Water Phenomena, N.M.
Burns and C. Ross, eds. Can. Center for Inland Waters Paper No. 6 and
U.S. Environmental Protection Agency Technical Report TS-05-71-2808-24
1972, pp. 85-119.
Cooke, G.D., M.R. McComas, D.W. Waller, and R.H. Kennedy. The Occurrence of
Internal Phosphorus Loading in Two Small, Eutrophic, Glacial Lakes in
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Dillon, P.O. and F.H. Rigler. A Test of a Simple Nutrient Budget Model
Predicting the Phosphorus Concentration in Lake Water. J. Fish. Res.
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258
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Fillos, J and H. Biswas. Phosphate Release and Sorption by Lake Mohegan
Sediments. Jour, of the Environmental Engineering Division, ASCE, 239-
249, 1976.
Fillos, J. and W.R. Swanson. The Release Rate of Nutrients from River and
Lake Sediments. Jour. Water Pollution Control Fed., 47:1032-1042, 1975.
Freedman, P.L. and R. P. Canale. Nutrient Release from Anaerobic Sediments,
Jour, of the Environmental Engineering Division, ASCE, 233-244, 1977.
Funs, G.W., S.P. Allen, L.J. Hetling and T.J. Tofflemire. Restoration of
Lower St. Regis Lake (Franklin County, New York). Ecological Research
Series Report EPA-600/3-77-021. U.S. Environmental Protection Agency,
Corvallis, Oregon, 1977, 106 pp.
Kamp-Nielsen, L. Mud-water Exchange of Phosphate and Other Ions in Undisturb-
ed Sediment Cores and Factors Affecting the Exchange Rates. Arch.
Hydrobiol., 73:218-237, 1974.
Kamp-Nielsen, L. Seasonal Variation in Sediment-Water Exchange of Nutrient
Ions in Lake Esrom. Verh. Internat. Verein. Limnol, 19: 1057-1065,
1975.
Kemp, A.L.W. , C.B.J. Gary and A. Murdrochova. Changes in C, N, P and S in
the Last 140 Years in Three Cores from Lake Ontario, Erie and Huron. In:
Nutrients in Natural Waters, H.E. Allen and J.R. Kramer, eds. Wiley,
New York, 1972, pp. 251-280.
Larsen, D.P., K.W. Malueg, D.W. Schults, and R.M. Brice. Response of Eutro-
phic Shagawa Lake, Minnesota, U.S.A., to Point Source, Phosphorus Reduc-
tion. Verh. Internat. Verein. Limnol., 19:884-892, 1975.
Larsen, D.P., D.W. Schults and K.W. Malueg. Summer Internal Phosphorus
Supplies in Shagawa Lake, Minnesota. Submitted to Limnol. and Oceanogr,
1978.
Larsen, D:P., J. Van Sickle, and K.W. Malueg. The Effect of Wastewater
Phosphorus Removal on Shagawa Lake: Phosphorus Supplies, Lake Phosphorus
and Chlorophyll a. Manuscript in preparation. 1978.
Lee, G.F- Factors Affecting the Transfer of Materials between Water and
Sediments. Univ. of Wisconsin, Eutrophication Information Program.
Literature Review No. 1. Madison, Wisconsin. 1970.
Lee, G.F. Role of Phosphorus in Eutrophication Control and Diffuse Source
Control. Water Research, 7:111-128, 1973.
Lee, G.F., W.C. Sonzogni and R.D. Spear. Significance of Oxic vs. Anoxic
Conditions for Lake Mendota Sediment Phosphorus Release. In: Proceed-
ings of an International Symposium on Interactions Between Sediments and
Freshwater, Amsterdam, Netherlands, September 6-10, 1976, H.L. Golterman,
ed. Dr. W. Junk, B.V. Publishers, Hague, 1977, pp. 307-312.
259
-------
Lie, G.B. Phosphorus Cycling by Freshwater Macrophytes-The Case of Shagawa
Lake. Ph.D. Thesis, University of Minnesota, Minneapolis, Minnesota.
1977.
Malueg, K.W., D.P. Larsen, D.W. Schults and H.T. Mercier. A Six-Year Water,
Phosphorus, and Nitrogen Budget for Shagawa Lake, Minnesota. J. of
Environmental Quality, 4:236-242, 1975.
Mortimer, C.H. The Exchange of Dissolved Substances between Mud and Water in
Lakes. I and II. J. Ecol., 29:280-329,1941.
Mortimer, C.H. The Exchange of Dissolved Substances between Mud and Water in
Lakes. Ill and IV. J. Ecol., 30:147-201, 1942.
Mortimer, C.H. Chemical Exchanges between Sediments and Water in the Great
Lakes—Speculations on Probable Regulatory Mechanisms. Limnol. Oceanogr.
16:387-404. 1971.
Nicholls, K.H. and P.J. Dillon. An Evaluation of Phosphorus-Chlorophyll-
Phytoplankton Relationships for Lakes. Int. Rev. ges. Hydrobiol. In
press, 1977.
Rigler, F.H. Nutrient Kinetics and the New Typology. Verh. Internat. Verein.
Limnol. , 19:197-210, 1975.
Schults, D.W., K.W. Malueg, and P.O. Smith. Limnological Comparison of
Culturally Eutrophic Shagawa Lake and Adjacent Oligotrophic Burntside
Lake, Minnesota. The American Midland Naturalist. 96:160-178, 1976.
Serruya, C., M. Edelstein, U. Pollingher and S. Serruya. Lake Kinneret
Sediments: Nutrient Composition of the Pore Water and Mud Water Ex-
changes. Limnol. and Oceanogr., 19:489-508, 1974.
Shapiro, J. , W.T. Edmondson and D.E. Allison. Changes in the Chemical
Composition of Sediments of Lake Washington, 1958-1970. Limnol. and
Oceanogr., 16:437-452, 1971.
Sommers, L.E. R.F. Harris, J.D.H. Williams, D.E. Armstrong and J.K. Syers:
Fractionation of Organic Phosphorus in Lake Sediments. Soil Sci. Soc.
Amer. Proc., 36:51-54, 1972.
Sonzogni, W.C. Effect of Nutrient Input Reduction on the Eutrophication of
the Madison Lakes. Ph.D. Thesis, University of Wisconsin, Madison,
Wisconsin, 1974.
Sonzogni, W.C., P.C. Uttormark, and G.F. Lee. A Phosphorus Residence Time
Model: Theory and Application. Water Research. 10:429-435,1976.
Sonzogni, W.C. D.P. Larsen, K.W. Malueg and M.D. Schuldt. Use of Large
Submerged Chambers to Measure Sediment-Water Interactions. Water Re-
search, 11:461-464, 1977.
260
-------
Stauffer, R.E. and G.F- Lee. The Role of Thermocline Migration in Regulating
Algal Blooms. In: Modeling the Eutrophication Process. Proceedings of
a Workshop at Utah State University. E.J. Middlebrooks, D.H. Falkenburg,
and I.E. Maloney, eds., 1973, pp. 73-82.
Vollenweider, R.A. Scientific Fundamentals of the Eutrophication of Lakes
and Flowing Waters, with Particular Reference to Nitrogen and Phosphorus
as Factors in Eutrophication. OECD Technical Report DAS/CSI/68.27.
1968, 159 p.
Vollenweider, R.A. Advances in Defining Critical Loading Levels for Phospho-
rus in Lake Eutrophication. Mem. 1st. Ital. Idrobiol., 33:58-83, 1976.
Welch, E.G. Nutrient Diversion: Resulting Lake Trophic State and Phosphorus
Dynamics. Ecological Research Series Report EPA-600/3-77-003. U.S.
Environmental Protection Agency. Corvallis, Oregon. 1977, 100 p.
Williams, J.D.H., J.K.Syers, D.E. Armstrong, and R.F. Harris. Characteriza-
tion of Inorganic Phosphate in Noncalcareous Lake Sediments. Soil Sci.
Soc. Am. Proc. , 35:556-561, 1971.
Williams, J.D.H., J.K. Syers, R.F. Harris, and D.E. Armstrong. Fractionation
of Inorganic Phosphate in Calcareous Lake Sediments. Soil Sci. Soc, Am.
Proc. , 35:250-251, 1971.
Williams, J.D.H. and T. Mayer. Effects of Sediment Diagenesis and Regenera-
tion of Phosphorus with Special Reference to Lakes Erie and Ontario.
In: Nutrients in Natural Waters, H.E. Allen and J.R. Kramer, eds.
Wiley-Interscience. New York, N.Y. 1972, pp. 281-315.
Williams, J.D.H., T.P. Murphy and T. Mayer. Rates of Accumulation of Phospho-
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439, 1976a.
Williams, J.D.H., J.M. Jaquet and R. L. Thomas. Forms of Phosphorus in the
Surficial Sediments of Lake Erie. J. Fish. Res. Board Can., 33: 413-429,
1976b.
261
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THE REGULATION GUIDELINES AND CRITERIA
FOR THE DISCHARGE OF DREDGED MATERIAL:
PREDICTION OF POLLUTION POTENTIAL
R. M. Engler
U. S. Army Engineer Waterways Experiment Station
Environmental Effects Laboratory
Vicksburg, Mississippi 39180
ABSTRACT
Guidelines and criteria have been published for the
ecological evaluations of the discharge of dredged and
fill material into inland waters and the transportation
of dredged material for dumping into ocean waters. These
guidelines and criteria were published in the Federal
Register, Vol. 40, No. 173, Friday, 5 September 1975, and
Vol. 42, No. 7, Tuesday, 11 January 1977, respectively,
for inland and ocean dumping. Implementation manuals have
subsequently been published and are discussed herein.
Relevant dredged material research are also presented.
These manuals present evaluative procedures for pollution
evaluation.
INTRODUCTION
INLAND DUMPING GUIDELINES
Interim Guidance Published for Implementation of Section 404
Control of the discharge of dredged or fill material to minimize environ-
mental impacts is the requirement of Section 404(b)(l) of Public Law (PL) 92-
500 (Federal Water Pollution Control Act Amendments of 1972). Rules and
regulations providing this control were published in the Federal Register
(Vol. 40, No. 173, Friday, 5 September 1975) by the Environmental Protection
Agency (EPA). These regulations specify that EPA, in conjunction with the
Corps of Engineers (CE), will publish a procedures manual for the implementa-
tion of the regulations. The manual will provide technical guidance for the
evaluation of proposed discharges of dredged or fill material into navigable
waters as required by Section 404(b) of the Federal Water Pollution Control
Act Amendments of 1972.
Pending publications of the procedures manual, District Engineers are to
furnish interim guidance to permit applicants concerning the applicability of
263
-------
specific approaches or procedures to be used in the evaluation process. Con-
sequently, at the request of the Office, Chief of Engineers, the Environmental
Effects Laboratory (EEL) of the Waterways Experiment Station (WES) initiated
development of this interim guidance for use by District Engineers in evalu-
ating permit applications. This was published and distributed in May 1976 to
all Corps field elements in a document entitled "Ecological Evaluation of
Proposed Discharge of Dredged or Fill Material into Navigable Waters" (referred
to as the "Interim Guidance" and available from WES as Dredged Material Re-
search Program (DMRP) Miscellaneous Paper D-76-17).
The procedures included in the Interim Guidance represent the current
state-of-the-art in the dynamically evolving fields of aquatic and sediment
chemistry and biology, and attempt to provide a balance between technical
state-of-the-art and routinely implementable guidance for performing the
evaluation specified in the Federal Register. Evaluation of ecological effects
consists of two phases: selection of the appropriate test or evaluation pro-
cedures and the interpretation of results for assessment of potential problems.
The Interim Guidance defines the applicability of testing procedures to the
evaluation specified in the Federal Register and presents limitations in
interpreting the results.
The Interim Guidance is applicable to all activities involving the dis-
charge of dredged or fill material into navigable waters. The procedures pre-
sented are useful in evaluating the discharge and overflow from hopper dredges;
hydraulic pipeline discharges; the discharge and overflow from bottom and end
dump barges and scows; and the runoff, effluent, or overflow from a confined
land or water disposal area.
General approaches required for ecological evaluation involve estimation
of physical effects and chemical-biological interactive effects, both of which
are discussed in the Interim Guidance. Procedures for alternate site compari-
sons are also presented. Detailed procedures include those for conducting the
elutriate test and examining the mixing zone that must be used in interpreta-
tion of the elutriate test, performing bioassays, conducting total or bulk
sediment analyses, and evaluating biological community structure.
The scope and comprehensiveness of the required evaluation may be seen in
Figure 1, taken from the Interim Guidance, which shows the sequence of evalua-
tions that must be applied. The Interim Guidance follows the general priority
of importance of testing and evaluation procedures and general order of test
application given in the Federal Register.
During conduct of the DMRP, it has become apparent that an understanding
of the potential for ecological harm from the discharge of dredged or fill
material into wetland and aquatic areas requires substantial state-of-the-art
improvement in a number of fundamental technological areas. Therefore, such
state-of-the-art improvements were included in appropriate DMRP tasks and work
units and already have provided the basis for the evaluation procedures as well
as the discussions in the applicability and limitations of test results in the
Interim Guidance. Contributing DMRP tasks, primarily those in the Environmen-
tal Impacts and Criteria Development Project, are listed in Table 1. The ap-
propriate tasks are listed with the respective evaluation category from the
Federal Register.
264
-------
ECOLOGICAL EVALUATION OF PROPOSED DISCHARGE
Apply Evaluations in Federal Register
1
Wet
Eval
1
Water
Eff
\
Ben
Eff
i
Examine Character of
Compare with Propo
I
Eff
p
lands
DrpHgpH Material anri 4
sed Discharge Sites ~~
r
ical
ects
uation Chemical-Bioloaical ^ Exclusion
Interactive Effects Further Te
t
Column |-
ects Si
Compa
!
thos
ects Water
, , Eff
Total Sediment
•Analysis •— •
EluL
r Te
Community (NO RE,
Strurturp
Water-
Conside
i
te
rison (NO EXCLUS
_^ 1
rnlnmn ^ f
ects
f ^ ^
n'ate ^ Mixing
st — — uj Z(Jne
1 "^ / 1 ^»^
EASE) - u ^
Duality Water-Quality
rations Considerations
t t
Proposed Discharge
Allowed
Proposed Discharge
Denied
on of
from (EXCLUSION) —
sting
ION)
1 1
Effects on
Benthos
-- 1
' — .^ Bioassav
* 1
Additional Information
i
Figure 1
265
-------
TABLE 1. DMRP TASKS PROVIDING SIGNIFICANT INPUT TO THE INTERIM GUIDANCE
Evaluation Category*
DMRP Task
PHYSICAL EFFECTS
Wetlands Evaluation
Water Column Effects
Benthic Effects
4A Marsh Development
1A Aquatic Disposal Field Investigations
ID Effects of Dredging and Disposal on Aquatic
Organisms
1A Aquatic Disposal Field Investigations
ID Effects of Dredging and Disposal on Aquatic
Organisms
CHEMICAL-BIOLOGICAL
INTERACTIVE EFFECTS
Water-Column Effects
Elutriate test
Mixing Zone
Bioassay
Effects on Benthos
Bioassay
1C Effects of Dredging and Disposal on Water
Quality
IE Pollution Status of Dredged Material
2D Confined Disposal Area Effluent and
Leachate Control
1A Aquatic Disposal Field Investigations
IB Movements of Dredged Material
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on Aquatic
Organisms
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
IB Movements of Dredged Material
ID Effects of Dredging and Disposal on Aquatic
Organisms
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on Aquatic
Organisms
IE Pollution Status of Dredged Material
ITE COMPARISON
Total Sediment
Community Structure
1C Effects of Dredging and Disposal on Water
Quality
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
* From Figure 1.
266
-------
The Interim Guidance, however, is not intended to establish standards or
rigid criteria and should not be interpreted in such a manner. Therefore, the
document attempts to provide a balance between the technical state-of-the-art
and routinely implementable guidance for using the procedures specified in the
Federal Register and is expected to provide a continuity among the Corps
Districts' and the EPA's evaluation program for Section 404 permit activities.
The Interim Guidance is particularly important in forming a foundation to
be augmented by more meaningful and comprehensive evaluation procedures and
guidelines as these evolve from current and future DMRP and EPA environmental
research. Interagency coordination of the respective programs and development
of a joint agency procedures manual is currently being implemented by the
EPA/CE Executive Committee on Criteria for Dredged and Fill Material. It is
anticipated that the Interim Guidance will be updated routinely through this
interagency committee as new and more implementable evaluation procedures are
developed and verified. The Interim Guidance will remain in effect until pub-
lication of the joint agency procedures manual.
OCEAN DUMPING CRITERIA
Implementation Manual Published for Section 103 of PL 92-532 (Marine
Protection, Research, and Sanctuaries Act of 1972)
An ecological evaluation of the proposed discharge potential for environ-
mental impact is required by Section 103 of PL 92-532 (Marine Protection,
Research, and Sanctuaries Act of 1972). Criteria for these evaluations were
published in the Federal Register (Vol. 42, No. 7, Tuesday, 11 January 1977)
by the EPA. These criteria specified in Section 227.27(b) that the EPA
jointly with the CE would publish an implementational manual pursuant to the
criteria. The Implementation Manual would provide procedures for the evalua-
tion of the potential environmental impacts of the discharge of dredged
material into ocean waters: an evaluation that is required in considering
permit applications for the transportation of dredged material for ocean
dumping.
The task of developing the specific approaches and procedures to be used
in the evaluation process was undertaken by the EPA/CE Technical Committee on
Criteria for Dredged and Fill Material (see DMRP Information Exchange Bulletin
MP D-76-4, April 1976). At the request of the Office, Chief of Engineers, and
the Marine Protection Branch (EPA), the EEL of WES published this manual for
the evaluation of permit applications and development of statements of
findings.
Preparation and publication of the Implementation Manual was conducted
under the technical guidance of Dr. Richard K. Peddicord, EEL. Dr. Peddicord
also co-chairs the Bioassay/Bioevaluation Subcommittee of the Technical Com-
mittee with Dr. Jack H. Gentile of the Environmental Research Laboratory, EPA,
Narrangansett, Rhode Island.
The manual was published and distributed in July 1977 to all Corps and
EPA field elements in a document entitled "Ecological Evaluation of Proposed
Discharge of Dredged Material into Ocean Waters" (referred to as the Imple-
267
-------
mentation Manual and available from WES as a joint EPA/CE publication). Pro-
cedures in the Implementation Manual represent a multidisciplinary effort of
both agencies to develop procedurally sound, routinely imp!ernentable guidance
for complying with the Federal Register. Evaluation of ecological effects
consists of two phases: selection of the appropriate tests or evaluation pro-
cedures and the interpretation of results for assessments of potential problems.
The Implementation Manual defines the applicability of testing procedures to
the evaluations specified in the Federal Register and presents limitations in
interpreting the results.
The Implementation Manual is applicable to all activities involving the
discharge of dredged material into ocean waters. The procedures presented are
useful in evaluating the discharge from hopper dredges and from bottom- and
end-dump barges and scows.
General approaches required for ecological evaluation involve estimation
of potential impacts of the liquid, suspended particulate, and solid phases of
dredged material; estimation of the bioaccumulation potential; and estimation
of initial mixing. Detailed procedures include sediment and water sample col-
lection, preparation, and preservation; chemical analysis of the liquid phase;
bioassays of liquid, suspended particulate, and solid phases; estimation of
bioaccumulation potential; the estimation of initial mixing, evaluation of
prohibited materials; and interpretation of tract contaminant requirements.
The scope and comprehensiveness of the required evaluation may be seen in
Figure 2, taken from the Implementation Manual, which shows the sequence of
evaluation that must be applied. The Implementation Manual follows the general
priority of importance of testing and evaluation procedures and the general
order of test application given in the Federal Register.
During the conduct of the DMRP, it became apparent that an understanding
of the potential for ecological harm from the discharge of dredged material
into aquatic systems requires substantial state-of-the-art improvement in a
number of fundamental technological areas. Therefore, such state-of-the-art
improvements were included in appropriate DMRP tasks and respective work units
and already have provided the basis for the evaluation procedures as well as
the discussion of the applicability and limitations of test results in the
Implementation Manual. Contributing DMRP tasks, primarily those in the
Environmental Impacts and Criteria Development Project (EICDP) managed by Dr.
Engler, are listed in Table 2. The appropriate tasks are listed with the re-
spective evaluation category from the Federal Register. Related research by
the EPA was coordinated through the Technical Committee.
The Implementation Manual, however, is not intended to establish standards
or rigid criteria and should not be interpreted in such a manner. Therefore,
the document attempts to provide a balance between the technical state-of-the-
art and routinely implementable guidance for using the procedures specified in
the Federal Register and is expected to provide a continuity among the Corps
Districts' and the EPA's evaluation programs for Section 103 permit activities.
The Implementation Manual is particularly important for forming a founda-
tion to be augmented by more meaningful and comprehensive evaluation procedures
268
-------
ECOLOGICAL EVALUATION OF PROPOSED DISCHARGE
Apply Evoluations in 33 CFR 209.120
or 33 CFR 209.145
TP11
Applicability of Criteria ._ . .
Part 227 /SubpartA
TP12-36
Environmental impact /Subpart B
TP12
Prohibited Materials /Sec 2275
DENY PERMIT
Sec 227. 5
TPI3
Exclusion from Technical Evaluation / Sec 22713 (b)
Exclusion Disallowed /Sec 22713 (c)
(Benthic Impacts)
Exclusion Allowed
(Water Column Impacts)
TP 18,20-22
Solid Phase Bioassay
Sec22713(cX3)
Appendix F
TP18.I9
Suspended Paniculate Phase Bioassay
Sec22713(c)<3)
Appendices D and E
TP 16-18
Liquid Phase Bioassay
Sec 22713 (c) (2)
Appendices D and E
TP 23-25
Bioaccumulation
Sec 2276fc)(2)/227.6(c)(3)
Appendix G
TP 26-29
Initial Mixing
Sec22713(c)/22729
Appendix H
IP 34
Show Material
Environmentally Acceptable
Sec2276(f)/2276(g)
TP15
Water Quality Criteria
Sec22713(cX2)/22713(d)
Appendix C
TP33
Possible Special Studies
Sec 2276 (d)
TP 35
General Compatibility of the Material
With the Disposal Site
Sec 2279/227.10
TP 37
Need for Ocean Dumping
Subpart C
TP 38
Impacts on Esthetics, Recreation 8 Economics
Subpart D
TP 39
Impacts on Other Uses of the Oceans
Subpart E
TP 4O
Site Management Considerations
Sec 22713 / 228.4 (e)/228S/22ai2
Note: Numbers within the boxes refer to Sections
and paragraphs in the Register.
Paragraph (TP) and appendix citations
inside the boxes refer to this manual.
TP 41
Request Additional Information
Sec 225.2 (b)
Figure 2
269
-------
TABLE 2. DMRP TASKS PROVIDING SIGNIFICANT INPUT
TO THE IMPLEMENTATION MANUAL
Evaluation Category*
DMRP Task
Liquid Phase Chemical Tests
Water-Quality Criteria
Initial Mixing
Bioassay
Suspended Particulate Bioassay
Solid Phase Bioassay
Initial Mixing
Bioaccumulation
Trace Contaminants
1C Effects of Dredging and Disposal on
Water Quality
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
IB Movements of Dredged Material
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
IB Movements of Dredged Material
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
1A Aquatic Disposal Field Investigations
1C Effects of Dredging and Disposal on
Water Quality
ID Effects of Dredging and Disposal on
Aquatic Organisms
IE Pollution Status of Dredged Material
* From Figure 2.
270
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anci guidelines as these evolve from current and future DMRP and EPA environ-
mental research. Interagency coordination of the respective programs and the
development of the joint agency procedures manual is being implemented by the
LPA/CE Technical Committee of Criteria for Dredged and Fill Material. It is
anticipated that the Implementation Manual will be updated routinely through
this interagency committee as new and more implementable evaluation procedures
Are developed and verified. The Implementation Manual will remain in effect
until publication of a new edition of the joint agency manual.
INTERAGENCY COORDINATION
Publication of the EPA/CE Technical Committee's First Annual Report
The joint Technical Committee on Criteria for Dredged and Fill Material
is co-chaired by Dr. Frank Wilkes of the EPA and Dr. Robert M. Engler of the
Corps. The First Annual Report presents the first year's effort to coordinate
and disseminate results of agency research related to regulatory functions
pursuant to Section 404 and 103 of PL 92-500 and 92-532, respectively.
A major goal of the Technical Committee is the development of a compre-
hensive manual for technical implementation of all ecological testing phases
of PL 92-500 and 92-532. (Publication of the Implementation Manual for Section
103 of PL 92-532 is discussed in the preceding paragraphs.) Other objectives
of the Technical Committee are to recommend needed research priorities in order
to implement fully Sections 404 and 103, establish joint research projects and
priorities, conduct joint program reviews, avoid duplication of effort, and
exchange and disseminate research results. The Technical Committee will also
review and evaluate interim testing procedures promulgated by the CE for im-
mediate implementation by field units. The group was also constituted to make
recommendations to top-level agency management.
The Technical Committee was organized as an interagency committee limited
to staff who have broad knowledge, responsibilities, and understanding of needs
for research programs in dredges and fill material discharge activities. The
Technical Committee consists of six subcommittees co-chaired by EPA and CE
personnel: The Bioassay/Bioevaluation, Area Definitions, Contaminants, Physi-
cal Impacts, Mixing Zone, and Fill Material Subcommittees. The scope of the
Technical Committee and respective subcommittees includes all pertinent re-
search (past, present, and future) conducted to determine the potential
usefulness of or to modify methodologies to predict and determine ecological
impacts. It also includes the assembly and synthesis of technical information
for the purpose of developing an implementation manual suitable for conducting
the evaluation mandated by both Section 404 and 103 of PL 92-500 and 92-532,
respectively.
The following members are currently appointed by the respective agencies:
271
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EPA CE
Dr. Frank Wilkes, Co-chairman Dr. Robert M. Engler, Co-chairman
Dr. William Brungs Mr. M. Burton Boyd
Dr. Mark Carter Dr. John Harrison
Mr. William S. Davis Dr. John W. Keeley
Dr. Jack Gentile Dr. Richard K. Peddicord
Dr. Harold Kibby Dr. Roger T. Saucier
Dr. Paul Lefcourt
Dr. Michael D. Mull in
Presented in the First Annual Report is a listing of all related EPA and
CE ongoing research programs directly related to dredged and fill material
regulatory functions. The listing is presented and discussed by each subcom-
mittee in order that there would be no duplication in recommending and assign-
ing priorities for needed research programs. Presented also is a listing and
thorough discussion of 16 research areas identified as requirements for com-
plete implementation of Sections 404 and 103, with each area of research as-
signed an overall priority, projected costs, and duration of study.
The effectiveness of the Technical Committee can best be judged by the
program coordination described in the Annual Report and by the research prior-
ities described therein. Other direct measures of effectiveness are the work-
shops sponsored through the subcommittees to pursue highly specific goals for
individual requirements of Section 404 and 103 of the Public Laws. Of equal
importance, however, has been the significantly increased level of communica-
tion among CE and EPA research elements and field units. This increased com-
munication will lead to a more effective and efficient management of each
agency's respective regulatory and research program.
Copies of the report may be purchased from the National Technical Informa-
tion Service (address: 5285 Port Royal Road, Springfield, Virginia, 22151).
In ordering, the NTIS ID number ADA 040 662 should be mentioned.
REFERENCES
1. Environmental Effects Laboratory, "Ecological Evaluation of Proposed
Discharge of Dredged or Fill Material into Navigable Waters," Miscellan-
eous Paper D-76-17, May 1976, U. S. Army Engineer Waterways Experiment
Station, CE, Vicksburg, Mississippi.
2. Environmental Effects Laboratory, Dredged Material Research Program
Fourth Annual Report, January 1977, U. S. Army Engineer Waterways Experi-
ment Station, CE, Vicksburg, Mississippi.
3. EPA/CE Technical Committee on Criteria for Dredged and Fill Material,
"Ecological Evaluation of Proposed Discharge of Dredged Material into
Ocean Waters; Implementation Manual for Section 103 of Public Law 92-532
(Marine Protection, Research, and Sanctuaries Act of 1972)," July 1977,
published by the Environmental Effects Laboratory, U. S. Army Engineer
Waterways Experiment Station, CE, Vicksburg, Mississippi.
272
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DENSIFICATION, TREATMENT, AND MANAGEMENT
OF DREDGED MATERIAL DISPOSAL AREAS
C. C. Calhoun, Jr.
U. S. Engineer Waterways Experiment Station
Environmental Effects Laboratory
Vicksburg, Mississippi 39180
ABSTRACT
Work within the Disposal Operations Project of
the Dredged Material Research Program related to the
densification and treatment of dredged material and
the management of containment areas is described. The
process of dewatering/densifying dredged material
through progressive trenching is discussed and the
results of a major field test are given. Results of
laboratory and field tests on the treatment of contami-
nated dredged material with chemical flocculants are
presented. An integrated management approach for
containment areas is presented through a generalized
decision network.
INTRODUCTION
The U. S. Army Corps of Engineers' Dredged Material Research Program
(DMRP) is a comprehensive five-year research program initiated in March 1973
to address problems associated with the disposal of dredged material. The
program is being administered by the Environmental Effects Laboratory (EEL)
of the U. S. Army Engineer Waterways Experiment Station, Vicksburg, Missis-
sippi. The DMRP is divided into four projects. Most of the engineering or
operational research is being conducted within the Disposal Operations Project
(OOP). At the meeting in Japan in October 1976, a paper was presented des-
cribing OOP work units dealing with dredged material densification and treat-
ment of contaminated material (1). The paper presented here provides an
update of the work described in the previous paper, which will be referenced
frequently to minimize the length of this paper and to avoid needless repeti-
tion.
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DREDGED MATERIAL DENSIFICATION
BACKGROUND
Within the scope of the DMRP, the principal reason for dewatering or
densifying dredged material is to obtain additional volume in the containment
area and thereby increase its service life. Therefore, dredged material
densification should not be confused with dredged material stabilization
though often times one results from the other. In some instances dredged
material can be stabilized (such as by the use of various chemicals), but the
volume occupied by the material within the containment area may not be de-
creased. Two additional benefits of dredged material densification may be
the creation of fast land or changing the character of the wet dredged mater-
ial into a drier more desirable form that may be put to some productive use.
Work within the DMRP has been aimed primarily at dewatering or densifying
fine-grained (silt and clay) dredged material. Fine-grained dredged material
is the most difficult material to dewater, but it provides the most volume
gain when dewatered. In fact, little volume gain is obtained in materials
with liquid limits less than about 50 (2). Figure 1 from Reference 2 shows
the relationship between volume gained through reduction in water content
versus the plasticity of the material.
The state-of-the-art and state-of-the-practice is such that practically
any material may be dewatered; the limiting factor for dredged material is
usually cost. Certainly a system that is economical for dewatering a founda-
tion for a building may not be at all economical for dewatering hundreds or
thousands of hectares within dredged material disposal areas. Therefore, in
many cases, cost is the basis for establishing the feasibility of a particular
dewatering technique.
In the first paper, all techniques being evaluated by the DMRP were
discussed, including low voltage gradient electro-osmosis, vacuum wellpoints,
mechanical crust stabilization, capillary wicks, underdrainage, and progres-
sive trenching. Results of all of the investigations will be reported in
detail in the report now being prepared on the field studies (3). Based on
the results of these studies, it appears that the most economical technique
for dewatering dredged material is progressive trenching. For that reason,
this technique will be discussed in some detail.
PROGRESSIVE TRENCHING
In the early phases of the DMRP, it was assumed that the relatively thin
desiccation crust that developed on most all disposal areas containing fine-
grained dredged material inhibited water removal by evaporation from the
underlying wet material and was the cause for the material remaining wet for
years. However, after observing numerous containment areas, it became obvious
that the formation of the crust was not the sole reason for the underlying
material remaining at very high water contents. In most instances, the crust
observed in the field was relatively thin (less than 0.3 m). But in some
cases where the net evaporation (total evaporation minus rainfall) was extreme-
ly high, the crust was observed to extend to much greater depths (in some
274
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Figure 1. Volume changes with moisture
content decreases.
275
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cases greater then 4m). It became apparent that disposal areas act as catch
basins or bathtubs. In many of the areas, the net evaporation rate was low
or even negative; therefore, perched water tables developed within the
containment areas.
Based on the field observations, the conclusion was that the desiccation
crusts extend to the depth of the top of the water table. The validity of
this observation was confirmed by controlled crust-formation tests (4). It
was decided that a potentially effective and inexpensive method of dewatering
fine-grained dredged material would be to promote the formation of the desic-
cation crust. This would involve the establishment of a good surface drainage
system to remove rainfall and other surface water from the site to take
advantage of the total rather than the net evaporation rate.
The problem then became how to create a drainage system on the very soft
dredged material within the containment areas. In other studies being conduc-
ted by the OOP, an inventory and evaluation of low-ground-pressure equipment
were made (5). It appeared that the Riverine Utility Craft or RUC (Figure 2)
was uniquely suited for providing trenches in the soft material. The RUC, a
5,400-kg amphibious vehicle with 6.25-m-long twin helical screws, creates two
semicircular ruts or trenches as it moves across soft ground, thereby provid-
ing effective drainage trenches. The RUC was originally developed for mili-
tary purposes to fill the mobility gap between boats and conventional tracked
or rubber-tired vehicles.
A RUC was obtained from the U. S. Marine Corps, and field tests were
planned for a disposal site in Mobile, Alabama. The concept of progressive
trenching to be evaluated was to provide drainage trenches with the RUC while
the material is very soft. The flowline of the trenches must be maintained
below the bottom of the dessiccation cracks to allow water in these cracks to
drain. As the crust becomes thicker and dessiccation cracks become deeper,
the trenches must be progressively deepened to maintain drainage. It should
be remembered that the purpose of the trenches is to remove surface water,
not subsurface water. It was thought that as the crust became thicker more
conventional equipment could be used for the trenching.
The concept of progressive trenching is not new or completely original
to the DMRP. The Dutch have used a similar method known as "soil ripening"
for years in polder reclamation (6). In the Netherlands, a vehicle consider-
ably smaller then the RUC and known as the Amphirol is used for initial
trenching. The trenches are deepened with larve V-shaped wheels pulled
between dikes by cables until more conventional equipment can be used to
deepen trenches. Data are being exchanged on the ripening and progressive
trenching techniques. A committee such as the one with the Japanese is
presently being established by the Corps of Engineers and the European commun-
ity.
Field Tests
Field tests were initiated in August 1975 at the Upper Polecat Bay (UPB)
Disposal Area in Mobile, Alabama. The 34.4-hectare site was created in 1970
and was used for disposal of sediments from maintenance dredging of the
Mobile River and Harbor. The material placed in the area was predominantly
276
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RIVERINE UTILITY CRAFT
EMPTY WT (INCLUDING DRIVER & FUEL) 0990 V
GROSS WT (DRIVER, FUEL ft PAYLOAD 5900 I
LENGTH (OVERALL) 6-25 m
WIDTH (OVERALL) 4 27 n
HEIGHT (OVERALL. LESS WINDSHIELD) 2.34 m
ROTOR SPACING. CENTER TO CENTER 2.79 n
ROTOR DIAMETER (DRUM ONLY) 0-99 rr
ROTOR DIAMETER (OVER HELIX) '-47 "
ROTOR LENGTH (OVERALL) S'54 "
ROTOR LENGTH (IN CONTACT WITH GROUND, NO RUT) 4.95 n
GROUND CLEARANCE ]-2S "
FLOATING DEPTH (EMPTYi (WATER) °-55 "
FLOATING DEPTH ILOAOEO) (WATER) 0.61 n
1 1,000 L8)
13,000 LB)
20 S FT)
14 FT)
7.67 FT)
1 10 IN.)
39 IN.)
56 IN.)
222 IN.)
19S IN.)
49 IN.)
21.5 IN.)
24 IN.)
Figure 2. Detail and general specification for
Riverine Utility Craft
an organic clay sediment (CH) with a liquid limit of about 110 and a plasti-
city index of about 72. The depth of material in the site when tests were
initiated was about 4 m. The crust varied in thickness from 0.005 to 0.2 m
and the underlying material was at water contents exceeding the liquid limit.
A general plan view of the test site is shown in Figure 3 where individual
trenches are labeled A through I. All trenches were graded so water would
drain to the weirs. Trench spacings of 15, 46, and 76 m were included to
evaluate the effect of varied spacings. The north and south ends of UPB were
not trenched in order to conduct other dewatering experiments (3).
The sequence of trenching operations is shown in Figure 4. Although the
exact times the trenching operations were performed varied throughout the
site, a general schedule will be given here. The initial trenching with the
RUC was performed during October 1975. Figure 4a shows the trenches being
formed by the RUC. In Figure 4b tne effectiveness of the trenches is shown
by the water draining from the surrounding area after a rain. Trenches were
deepened for the next few months until May 1976 when the average thickness of
the crust was about 0.15 m. At this time a marsh dragline (Figure 4c) was
used to continue deepening trenches. This machine was a small conventional
dragline mounted on a pontoon chassis with 0.76-m-wide tracks. Approximately
5 months later when the depth of the crust averaged about 0.6 m, a conven-
tional dragline and chassis (Figure 4d) was able to operate on mats to con-
tinue deepening the trenches. By December 1976 trench depths up to 3-7 m
(near original foundation level) were reached adjacent to the south weir. In
other areas of the test site, trench depths of 1.8 to 3.6 m were reached.
Performance Predictions
The volume gain within a disposal area should occur from three sources:
formation of desiccation crust and cracks, consolidation of underlying dredged
277
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Figure 3. Plan view of progressive trenching
test section.
material, and, depending on water table conditions and soil properties,
consolidation of the foundation material. Techniques for estimating the
magnitude and rates of volume gains have been developed (3 and 7). The
magnitude of shrinkage from formation of the desiccation crust can be estima-
ted from a simple test where the slurry is placed in a mold and allowed to
dry. From this test the relationship between volume gain and water content
can be developed. Couple this information with techniques developed for
predicting rates of crust formation and the rate of volume gain can be esti-
mated.
Crust formation changes the effective stress acting on the underlying
dredged material and foundation. The effective stresses (and thus consolida-
278
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a. Trenches being formed by the RUC.
b. Water draining from surrounding area after rain.
Figure 4. Sequence of trenching operations.
279
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c. Marsh dragline deepening trenches.
d. Conventional dragline on mats deepening trenches.
28Q
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tion) will be increased in the dredged material as the water table is lowered.
If a perched water table within the dredged material is connected to the
water table within the foundation, the foundation material will consolidate
as the perched water table is lowered. For the UPB site, it was calculated
that there should be a 0.6-m settlement of the surface for each meter of
water table drawdown. Additional volume will be obtained from the dessicca-
tion cracks.
Results
Thirteen piezometers survived all trenching operations without damage
and trends of drawdown were practically identical for all piezometer loca-
tions. The average drawdown was 0.45 m and the average settlement was 0.29
m. The settlement would have been greater if the north and south ends of the
test site had been dewatered also. In addition the technique could be refined
based on these tests to increase the efficiency of the system. There was no
correlation between trench spacing and drawdown. This indicates the spacings
were appropriate for removing surface water.
CONCLUSIONS AND RECOMMENDATIONS
Based on the results of the field study and complementary studies, the
following conclusions and recommendations are made. More details and guidance
on progressive trenching techniques will be given in the synthesis report of
all dewatering techniques eveluated (8).
1. Densification and dewatering of fine-grained dredged material can be
induced by improving disposal area surface drainage and evaporative
drawdown of the internal water table. Densification and dewatering will
result from a combination of subcrust dredged material and foundation
consolidation under increased effective stress and shrinkage from evap-
orative drying above the lowered water table.
2. Construction of surface drainage systems by trenching within confined
disposal area is operationally feasible. Although the rate of settlement
can b.e estimated, trenching operations must remain flexible to adjust to
changing conditions within the disposal area.
3. As dredged material drying and crust formation progress, the trenching
system must be progressively deepened to allow continued drainage from
the crust and to promote further crust formation.
4. Trenching with the RUC appears to be the best available method to
initiate surface drainage trenches in disposal areas with crusts less
than 0.1-m thick.
5. Amphibious or marsh chassis draglines are effective in trenching opera-
tions when crust thicknesses are in excess of 0.15 m. Lightweight
draglines operating on mats can be employed when existing crust thick-
nesses are in excess of 0.3 m.
6. The magnitude of drawdown was not greatly affected by trench spacing.
It is recommended that RUC trenches be spaced close together in order to
remove as much surface water as possible. The use of the RUC allows
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large numbers of trenches to be formed in a relatively short period of
time. When conventional equipment is used, it probably will not be
economically or practically feasible to deepen every RUC trench.
7. Results of analyses made to predict the expected amount of sediment from
consolidation and shrinkage compared favorably with field-measured
behavior.
TREATMENT OF CONTAMINATED DREDGED MATERIAL
BACKGROUND
In the United States, treatment of dredged material prior to disposal
has rarely been required. In one instance, treatment for PCBs involving the
use of flocculants and activated charcoal was necessary before effluent could
be returned to the waterway from a confined disposal area. This is certainly
an exception; normally conventional dredged material containment and release
of effluents over weirs is sufficient treatment. However, it was realized by
the DMRP that there would probably be instances where additional treatment
would be necessary and the program would be incomplete if this aspect of
disposal was not addressed.
It is well known within the dredging-related community but not generally
understood outside the community that dredged material is not sewage sludge.
Consequently, treatment processes applicable to sewage sludge or waste water
are not always applicable to dredged material. The applicability of conven-
tional treatment processes to dredged material was evaluated early in the
DMRP (9). This study verified that most conventional waste water treatment
methods are not applicable to dredged material or are impractical because of
the relatively low organic content, high solids content, high magnitude and
variability of flow, and complex makeup of physical and chemical properties
of the material.
On the positive side, this and other studies indicated that practically
all contaminants are associated with the solid phase and not the fluid phase
of dredged material (9 - 12). Consequently, retention of solids within a
containment area generally eliminates the need for further treatment. For
this reason, emphasis within the DMRP was placed on treatment involving
providing maximum removal of solids prior to discharging effluent back into
the waterway. The two most promising methods appear to be filtration and
flocculation. Filtration studies have been completed and published (13).
Work on flocculants has been completed, but the results have not been pub-
lished to date. This section of the paper will discuss the results of the
flocculation studies. The discussion must be on a very general basis since
all data have not been analyzed and final conclusions have not been drawn in
all instances. More detailed information will be available at a later date.
LABORATORY STUDIES
Extensive laboratory studies of the effectiveness of flocculants were
conducted for the DMRP at the University of Southern California (14). The
studies included the following:
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1. Investigate the effectiveness of both conventional and polyelectro-
lite flocculants for the removal of the fine-sized fraction of
dredged materials that are likely to remain in suspension.
2. Determine the optimum dosage required for adequate flocculation of
the fines.
3. Correlate the characteristics of sediments with the type and
dosage of flocculants.
4. Evaluate the removal efficiency of contaminants in water columns
with and without polymer treatment.
5. Evaluate the effectiveness of treatment within the dredge pipe and
at the weir.
6. Compare the characteristics of flocculated sediments versus reset-
tled sediments.
7. Study the effect of salinity on the treatment of effluents.
8. Study the possibility of leaching contaminants from flocculated
sediments.
The results of the studies were based on tests conducted on 50 types of
polymers and conventional coagulants. Extensive laboratory experiments were
carried out to screen commercially available polymers and conventional coagu-
lants such as alum and ferric sulfate. It was found that the conventional
coagulants are unsuitable due to the large dosages and pH control required to
achieve acceptable effluent quality. There is also the problem of carryover
of trace metals from these conventional coagulants. Many high molecular
weight cationic and anionic polymers were found to be very effective for the
treatment of suspensions in the laboratory. Rapid removal of contaminants
was observed immediately after flocculation. When a detention time of a few
minutes is provided, the concentration of contaminants in the treated effluent
can be drastically reduced from the parts-per-mil1 ion range to the parts-per-
billion range.
It was found that the optimum dosage of a polymer is closely related to
the level of salinity and initial turbidity of the suspension. A suspension
with high salinity and low initial turbidity usually requires less polymer.
However, a suspension with high turbidity is easier to clarify by fast floe
formation. Treatment within the dredge pipe presents problems in determining
the optimum dosage due to the high variability of the material within the
pipe as well as requiring more polymer. The containment area actually acts
as a buffer and provides a more uniform material of lower solids concentration
coming over the weir. Parameters of gross content such as COD, TOC, and
particle size of sediments were found to be well correlated with optimum
dosage requirements. Therefore, these parameters could be useful in the
initial selection of the type of polymer and optimum polymer dosage.
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There is no significant difference in the physical properties of reset-
tled sediments with and without polymer treatment in terms of plastic limit,
liquid limit, and plasticity index. However, there is a slight increase in
the coefficient of permeability for the polymer-treated sediments.
An assessment of long-term mobilization of chemical constituents from
polymer-flocculated particles was also conducted to gain additional insight
concerning the possibility of release of contaminants to the water column.
In most cases, the polymer-treated particles did not show a significant
difference in the release of contaminants then that of untreated samples.
FIELD FLOCCULATION TESTS
The laboratory tests indicated that the use of flocculants was an
effective treatment method. The problem still remained as to how to apply
these findings to actual field operations. For a flocculant to be effective,
the chemical must come into contact with the soil particle, then time is
required for the floes to form, and then rather quiescent conditions must be
provided for the floes to settle. These steps are easy to control in the
laboratory. A full-scale test was conducted to see how well these factors
could be controlled under field conditions (15).
A schematic diagram of the field test is shown in Figure 5. The site
selected was an actual dredging project at a freshwater site on a river. An
18-in. (46-cm) dredge was working at the site. The test was designed to
evaluate the introduction of the flocculant in the pipeline and at the weir.
A booster pump was required because of the relief of the area. Introducing
the high molecular weight cationic polymer on the suction side of the dredge
was simulated by injecting the chemical on the suction side of the booster
pump. Other injection and/or sampling points allowed the evaluation of
various retention times within the pipe. Treatment at the weir required an
additional containment area to provide relatively quiescent conditions for
settling to occur. It is important to note that the polymer selected for use
in the field tests (based on a screening of many polymers) did not work well
on the sediments evaluated in the University of Southern California studies.
This emphasizes that there is no universal flocculant and each case must be
evaluated separately.
284
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1600' ±
926'
676'
659'
0
Lower Dike Booster Pump
Dredge
18" Dia. Steel Pipe-
224' of 30" Oia:-
Corrogated
Pipe
Lower
Containment
Dike
Upper
Containment
Dike
604'
—0-
(V)« Injection and/or Sampling Points
Figure 5. Schematic diagram of field flocculation test.
The supernate of initial samples taken directly from the dredge pipe had
high turb.idity averaging around 3000 NTU (Nephelometric turbidity units).
The polymer dosage used was 20 mg/Sl. For the particular polymer used in the
tests, the residence time in the pipe had little effect because the floes
formed rapidly and were extremely strong. When the concentration of solids
in the pipe was near the design concentration, the turbidity of the supernate
was drastically reduced (10-15 NTU). However, as solids concentrations
varied to either side of the design concentration, the turbidity was reduced
to only 1500 NTU. This supports the point made earlier that the side varia-
tion in flow and solids concentraion in the pipe makes it extremely difficult
if not impossible to determine the optimum dosage to provide the desired
results.
The tests where the chemical was pumped directly into the dredge pipe
identified another problem associated with this method. In order to inject
the chemical, a pump must be used to overcome the pressure in the pipe. In
most instances a very dilute polymer mixture is desired. This requires very
285
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large quantities of makeup water. For these tests less dilute polymer
mixtures than desired were used because sufficient makeup water was not
available.
For the tests conducted at the weir, the turbidity of untreated super-
nates (35-175 NTU) was much lower than that from the discharge at the pipe.
Dosages ranged from 10 to 36 mg/£ depending on the turbidity level. The
turbidity was generally reduced to 5 to 35 NTU. This indicates that some
control of the solids concentrations is necessary for effective use of poly-
mers. Problems of injecting the polymer at the weir are minimal when compared
to those of injecting into the dredge pipe; for these tests a gravity-feed
system was all that was required.
CONCLUSIONS
Flocculation can be an effective method of preventing contaminated
effluent from containment areas. Problems of implementing the treatment
under field conditions are formidable but can be overcome. Details on
implementation are not given here but will be published in Reference 15.
Treatment at the weir appears preferable to direct treatment in the dredge
pipe.
CONTAINMENT AREA MANAGEMENT
The preceding discussions have related to specific individual research
efforts within the OOP to improve disposal operations. However, it has been
the philosophy of the DOP that integrated disposal area management must be
accomplished if containment areas are to serve their designated purpose,
i.e., contain dredged material with the minimum environmental impact. This
includes managing the sites to minimize the land areas required for contain-
ment. This is also a requirement in recent legislation passed by the U. S.
Congress. Section 148 of Public Law 94-487, the Water Resources Development
Act states in part that the Corps of Engineers ". . .shall utilize and en-
courage utilization of such management practices . . . appropriate to extend
the capacity and useful life of dredged material disposal areas such that the
ne^d for new dredged material disposal areas is kept to a minimum. . ." To
assist Corps of Engineers' elements in planning for implementation of the
law, the DMRP prepared a special edition of its Information Exchange Bulletin,
which included as integrated management approach (17).
Figure 6, extracted from the Bulletin, presents a management decision
network. The network was developed to indicate how and where the individual
management guidelines being developed by the DMRP may be applied. The diagram
is not intended to be a complete decision making network but can be used to
idenfity critical areas where management decisions should be made. Since
environmental considerations may dictate the location of a new site or govern
the continued use of an existing site, an evaluation of these considerations
must be made in developing the overall management scheme. By the end of the
DMRP in March 1978, it is believed that practically all of the as yet un-
answered questions encountered when following the diagrams will be addressed
and proper guidance will be available to make sound engineering and scientific
judgments.
-------
OTHER DISPOSAL ALTERNATIVES ,
DETERMINE CAPACITY OF CONVENTIONAL
DISPOSAL AREA REQUIRED TO
CONTAIN SEDIMENT
. OTHER DISPOSAL ALTERNATIVES
DETERMINE EFFLUENT *ATER QUALITY
OR OTHER ENVIRONMENTAL PROTECTION
REQUIREMENTS TO BE MET
DETERMINE POTENTIAL ENVIRONMENTAL
PROBLEMS AND CONSTRAINTS
NE* DISPOSAL SITE
DEVELOP PRELIMINARY PLAN FOR
CONTAINING MATERIAL CONSIDERING
AVAILABLE POTENTIAL SITES
EXISTING DISPOSAL AREA
I ACTIVE OR FILLED!
DESIGN CONSIDERATION
1 OPTIMUM SIZE AND LOCATION OF SITE
2 LOCATION OF INLET AND OUTLET STRUCTURES
3 DIKE I INCLUDING INTERNAL! LAYOUT
4 DIKE DESIGN
S. OUTLET STRUCTURE DESIGN
« EFFLUENT TREATMENT FACILITIES
i ODOR AND MOSQUITO CONTROL
8. LANDSCAPING
1 OE»ATERING SYSTEM
10. 'MATERIAL HANDLING
1 £
A. DEWATERING CONCEPTS
TECHNIQUES INCLUDE PROGRESSIVE
TRENCHING GRAVITY AND VACUUM-
AIDED SUBORAIflS. ELECTRO-OSMOSIS
VEGETATION. WELLPOINTS. ETC.
•). REUSABLE SITE CONCEPTS
I METHOD AND EQUIPMENT
2- LEGAL AND POLICY CONSIDERATIONS
3. COSTS
4. SITE SELECTION
C TREATMENT CONCEPTS FOR CONTAMINATED
DREDGED MATERIAL
CONSIDER SITE MODIFICATIONS
AND OPERATIONAL PROCEDURES
n r
RAISE DIKES
K'OFFSITEMSTl
COARSE-GRAINED
REMOVE OR RELOCATE
MATERIAL FOR ADDITIONAL
VOLUME'
1. REMOVE OFFSITt
2. REMOVE FOR DIKE
CONSTRUCTION
3. RELOCATE FOR SURCHARGE
INADEQUATE OR EXCESSIVE CAPACITY
ADEQUATE CAPACITV
PREPARE FINAL PLANS FOR
CONSTRUCTION AND MANAGEMENT
OF CONTAINMENT AREA
IMPLEMENT PLAN AND DISPOSE
IN AREA
MONITOR PERFORMANCE AND
PLAN FOR REUSE AS NEEDED BASED
ON ACTUAL PERFORMANCE AS
COMPARED WITH PREDICTED
PERFORMANCE
Figure 6. Dredged material disposal - management decision network.
287
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CLOSING REMARKS
Since the SMRP is ongoing, answers to all questions being addressed are
not yet available. This paper is intended to familarize the reader with some
of the work and, when possible, present findings. All research in the DMRP
will be concluded in March 1978. All reports will be available by October
1978. The DMRP Information Exchange Bulletin is published approximately
monthly and provides up-to-date information on the program. The Bulletin
will be mailed directly to those requesting it.
REFERENCES
1. Calhoun, C. C. , Jr., "Dredged Material Densification and Treatment of
Contaminated Dredged Material," Management of Bottom Sediment Con-
taining Toxic Substances - Proceedings of the Second US-Japan
Experts Meeting, October 1976, Tokyo, Japan. EPA Ecological
Research Series 600/3-77-083, July 1977, EPA Environmental Research
Laboratory, Corvallis, Oregon.
2. Johnson, S. J. , _et al. , "State-of-the-Art Applicability of Conventional
Densification Techniques to Increase Disposal Area Storage Capacity."
Technical Report D-77-4, April 1977, U. S. Army Engineer Waterways
Experiment Station, Vicksburg, Mississippi.
3. Haliburton, T. A., "Dredged Material Dewatering Field Demonstrations at
Upper Polecat Bay Disposal Area, Mobile, Alabama," (in press), U.S.
Army Engineer Waterways Experiment Station, Vicksburg, Mississippi.
4. Brown, K. W. , and Thompson, L. J., "Feasibility Study of General Crust
Management as a Technique for Increasing Capacity of Dredged Mater-
ial Containment Areas," Technical Report (in press), prepared by
the Texas A&M Research Foundation under contract to the Environmen-
tal Effects Laboratory, U. S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
5. Willoughby, W. E. , "Assessment of Low-Ground-Pressure Equipment for Use
in Containment Area Operations and Maintenance (Synthesis of Re-
search Report)," Technical Report (in press), U. S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi. Also issued
as Engineering Manual EM 110-2-5000.
6. Adriaan Volker Dredging Company, "European Dredging Practices," Technical
Report (in press), prepared under contract to the Environmental
Effects Laboratory, U. S. Army Engineer Waterways Experiment Sta-
tion, Vicksburg, Mississippi.
288
-------
7. Palermo, M. , "An Evaluation of Progressive Trenching as a Technique of
Dewatering Fine-Grained Dredged Material," Miscellaneous Paper (in
press), U. S. Army Engineer Waterways Experiment Station, Vicksburg,
Mississippi.
8. Haliburton, T. A., "Guidelines for Densifying Dredged Material," Techni-
cal Report (in preparation), U.S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
9. Moore, T. K. , and Newbry, B. W. , "Treatability of Dredged Material
(Laboratory Study)," Technical Report D-76-2, Fedruary 1976, U. S.
Army Engineer Waterways Experiment Station, Vicksburg, Mississippi.
10. Chen, K. Y. , et al_. , "Research Study on the Effect of Dispersion,
Settling, and Resedimentation on Migration of Chemical Constituents
During Open-Water Disposal of Dredged Material," Contract Report D-
76-1, February 1976, U. S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
11. Brannon, J. M. , et al. , "Selective Analytical Partitioning of Sediment
to Evaluate Potential Mobility of Chemical Constituents During
Dredging and Disposal Operations," Technical Report 0-76-7, U. S.
Army Engineer Waterways Experiment Station, Vicksburg, Mississippi.
12. Engineering Science, Inc., "An Evaluation of Oil and Grease Contamination
Associated with Dredged Material Containment Areas," Contract
Report (in press), July 1977, U. S. Army Engineer Waterways Experi-
ment Station, Vicksburg, Mississippi.
13. Krize, R. J. , ejt a 1. , "Investigation of Effluent Filtering Systems for
Dredged Material Containment Facilities," August 1976, U.S. Army
Engineer Waterways Experiment Station, Vicksburg, Mississippi.
14. Wang, C. C. , and Chen, K. Y. , "Chemical Coagulation as a Means of
Treatment for Dredged Material (Laboratory Study)," (in press), U.
S. Army Engineer Waterways Experiment Station, Vicksburg, Missis-
's ippi.
15. Jones, R. H. , "Chemical Coagulation as a Means of Treatment for Dredged
Material (Field Study)," (in preparation), U. S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi.
16. Barnard, W. D., "Treatment of Contaminated Dredged Material," Synthesis
Report, (in preparation), U. S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
17. U. S. Army Engineer Waterways Experiment Station, Dredged Material
Research Exchange Bulletin, "Special Edition - Planning of Section
148 and 150 of Public Law 94-587," Vol. D-77-1, January 1977,
Vicksburg, Mississippi.
289
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APPENDIX
DREDGING DEMONSTRATION PROJECT: YOKKAICHI, JAPAN
A PROPOSAL FOR A JOINT US/JAPAN FIELD PROGRAM
Prepared by
Spencer A. Peterson and Richard J. Call away
Corvallis Environmental Research Laboratory
U.S. Environmental Protection Agency
Corvallis, Oregon 97330
INTRODUCTION
Exchange of information between the United States and Japan in the area
of managing bottom sediments containing toxic substances originated from a
1970 U.S.-Japan cabinet-level meeting on pollution which was held in Tokyo.
Both countries recognized the seriousness of the problem at that time, and in
the future if left unchecked. Several years of negotiations led to the first
technical experts' meeting in Corvallis, Oregon, in November, 1975; a joint
communique recommending that the exchange be continued and supported by the
two respective governments resulted.
At the first meeting, the possibility of initiating a joint U.S.-Japan
project was discussed. At the second meeting in Tokyo during 1976, it was
agreed that an area of mutual interest was a demonstration of advanced Japan-
ese dredging technology as it pertained to the removal of sediments containing
toxic substances. Initially the project was to have been conducted in the
United States but reconsideration of the logistics involved suggested that
Japan was a more feasible location, specifically in Yokkaichi Port.
UNITED STATES CONCERNS
The United States is concerned with three major aspects of dredging.
These include: 1) the dredge's effectiveness in minimizing the resuspension
of bottom sediments, 2) relative efficiencies of different types of dredge
systems and 3) treatment techniques applied to return flows. Specific ques-
tions to be addressed by a demonstration project should be:
1. What is the minimum water depth in which the various dredge systems
can work (oozer dredge, clean up dredge, etc.)?
2. To what depth is the sediment disturbed? For example, is it possi-
ble to remove only the top 6 - 10 cm of sediment without substan-
tially disturbing the deeper sediment layers?
3. What are the relative sustained sediment removal rates of special-
ized vs. conventional hydraulic dredges when sediment is removed
from various depths under the same conditions, i.e., sorted and
unsorted sediments, clays, organics, etc.?
291
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4. What are the sediment removal efficiencies in dense sediments such
as gravel and cobble?
5. What levels of turbidity or suspended solids are created, over what
area is the resuspension distributed, and how quickly is it dissi-
pated?
6. What percentage of dredged materials delivered to the disposal site
are solids, and how does the percentage vary with sediment type?
7. How do contaminant concentrations and volumes of return flow waters
from the disposal area vary among the different dredge systems under
the same conditions?
8. What is the cost per cubic meter of sediment removed by the differ-
ent systems?
9. Considering items 7 and 8, are savings realized with the oozer
systems compared to conventional hydraulic systems when it becomes
necessary to treat the return flow water?
10. How many operators are required for the specialized equipment and
how much crew training is required?
11. What are the concentrations of specific toxicants in the water in
the vicinity of the dredge head with respect to ambient levels?
All of the above questions are of concern to the United States. While we
have some problems similar to those in Japan, we also have two which differ
considerably. The problem of PCB clean-up in the Hudson River is complicated
by the fact that the highest concentrations of PCB are located in shoal areas
with gravel bottoms which are cluttered with logging and lumber processing
wastes. The kepone problem in the James River is unique because, although
similar to PCB in some respects, little is known about its specific charac-
teristics in an aquatic medium. The fact that both areas are located in a
running water environment is of further concern since downstream effects will
occur.
Since the major concern associated with dredging toxic substances is the
potential for the dredging activity to result in secondary pollution from the
resuspension, dispersion and subsequent resettling of bottom sediments, these
are the main areas the demonstration project should address. Associated ques-
tions such as dredging production rates, treatment techniques, and cost should
be considered also. It is recommended that a joint United States/Japanese
demonstration proposal addressing the major concerns be adopted and imple-
mented at the earliest possible date. A possible approach is suggested in the
following paragraphs.
PROPOSED DEMONSTRATION
The real danger from secondary pollution due to dredging toxic substances
stems directly from the chemical composition of the pollutants themselves and
292
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from the potential for altering their chemical composition as a result of
rapid oxygen depletion due to oxidation of organic sediments. The physical
characteristics of the substrate being dredged are also important because
finer grained sediments have a greater affinity for pollutants than do coarser
grained materials because of their proportionally higher surface to volume
ratio. The items discussed below are considered important enough to warrant
an international field effort yet tractable enough to ensure success in a
rather limited time frame.
1. It will be necessary to thoroughly characterize the sediments physic-
ally and chemically. This characterization should be consistent with current
Japanese standard methods and monitoring design. If such methods are not
available then the sediments should be characterized at a number of sites
similar to the experimental design proposed by the Japanese scientists for
examining benthic organisms. These analyses must describe changes with sedi-
ment depth down to the point of maximum dredging depth, so the potential for
resuspension might be assessed. Standard particle size fractional analyses
and chemical composition with particular reference to total mercury (THg) and
PCB should be conducted so that these factors can be accurately correlated.
Particle sizing from turbid water samples could be accomplished with a Coulter
Counter.
2. Pollutant concentrations in the disturbed water mass could be cor-
related with turbidity (transmissometer readings) early in the investigation
and subsequent measurements might be limited to additional turbidity fluctu-
ations. This would permit many more measurements to be made and thus increase
the precision of the results. This research item stems from Mr. E. Sato's
report on the excellent correlation between turbidity/suspended solids and
concentrations of THg, PCB, etc. (Sato, 1977).
The intensity of movement of turbidity clouds associated with dredging
activities are the most readily observed indicators of the bottom dispersion
of contaminants. Measurements of the turbidity and suspended solids concen-
trations of these clouds thus probably offer the most potential for direct
determination of their horizontal and vertical area of influence. Data from
this investigation should be analyzed by determining correlations between
total suspended solids concentrations (mg/1) as a function of light extinction
measurement by a beam transmissometer and displayed to show horizontal and
vertical extent of the area of influence.
It is recognized that any proposed experimental design may be altered by
the specific site conditions, i. e., tide, wind, harbor current characteris-
tics, etc. It should be noted that these conditions can be modeled numeri-
cally (Callaway and Koblinsky, 1977). Station locations would be altered as
the need arises once the actual sampling program begins.
Where bottom sediments are extremely viscous (very slow dispersal e.g.,
congealed oil) little turbidity might be experienced in the water column;
however, pollutants may still be relocated. In this case, underwater tele-
vision may be a necessary adjunct or possibly the only feasible method of
observation. Its use should receive strong consideration. Even in the case
of visible turbidity clouds, a videotape of the relative differences between
293
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the different dredge systems might prove to be of as much or more value than
quantitative measures of light transmission, suspended solids and temperature.
Another possibility consists of tracking the suspended matter acoustically as
has been done in the New York Bight (Proni, et a_L , 1976).
SUMMARY
In summary several questions remain unanswered about Japanese special-
ized dredges. The one of primary concern at this point is their relative
efficiency to minimize resuspension of bottom sediments and how that effi-
ciency compares to more conventional hydraulic dredges. Therefore, we propose
the following preliminary experimental approach, the intent being to make use
of a continuous observable field (total suspended solids vs. percent light
transmission) in conjunction with discrete water samples to:
1. Define the relative ability of the two dredge types to minimize
resuspension of bottom sediments and;
2. To assure that sampling is done in the proper location to observe
any differences. In the event of a highly viscous sediment, recourse to an
alternative, e.g., TV observation method, may be required. Data could be
presented in a manner similar to Callaway, et al. (1976). Water temperature
and salinity would also be measured in the working area and a number of grab
samples at the working site would be analyzed for other pollutants to include,
but not to be limited to, THg and PCB. Some samples would be split with half
of the same sample being shipped to the United States for analysis. This
would allow us to determine if any differences exist in analytical results and
how we might handle the differences in a jointly produced report. This infor-
mation will also permit us to make better use of and to interpret other Japan-
ese results which may be available to us.
Ideally, it would be most desirable to make the proposed measurements for
the oozer dredge while it worked alone, then make the same determinations for
the hydraulic dredge as it worked alone. This should be done under the same
conditions as nearly as possible and at the same site.
It is anticipated that it will require one week to make final on-site
plans and preparations for conducting the field sampling program once equip-
ment, vessel and scientific field party are on hand. It will require approx-
imately one more week to make measurements with a hydraulic dredge operating
alone and an additional week to repeat the measurements with the oozer dredge.
Some time will be required to dismantle, repack and ship materials back to the
U.S. as well as do some of the preliminary examination of the data. A total
of 3-4 weeks is anticipated. Agreement on the results and subsequent publi-
cation of same will require another month to six weeks of drafting and ex-
change of critical review.
It is proposed that the field investigation begin the first of March
1978. It is anticipated that at a minimum, two technical staff members from
the Corvallis Laboratory and a Corps of Engineers representative who is to-
tally familiar with dredging should be involved in the field experiments.
294
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Lack of familiarity with Yokkaichi Port by the United States (sampling
vessels, possible laboratory facilities, etc.) prohibits preparation of a
final demonstration plan and this paper provides only preliminary ideas which
are subject to modification. It should also be recognized that the proposal
addresses only the first step toward evaluating the Japanese dredging tech-
nology. Several other questions remain to be addressed at a later time.
POSTSCRIPT
While this preliminary plan was not presented during the formal confer-
ence at Easton, Maryland, it was discussed at length when the Japanese dele-
gation visited the Corvallis Environmental Research Laboratory following the
meeting. They chose to take the plan under advisement and to let us know at
the earliest possible date what their decision concerning the joint project
would be.
In January 1978 the United States was notified by the Japanese Ministry
of Transport (Mr. Hiroshi Suda) that that Agency had designed a research plan
and it would be conducted at Port Yokkaichi on March 8, 9 and 10, 1978.
United States representatives were invited to observe the demonstration exper-
iment. Since the United States was not invited to play a "hands on" role in
the experiment it was decided only one representative from EPA (Spencer A.
Peterson) and one from the Army Corps of Engineers (William D. Barnard) would
participate as observers.
The experiment began on schedule March 8, with the oozer dredge system
operating. The dredge crew appeared to be well organized and the experiment
proceeded without problems. The next day, March 9, the cleanup dredge system
performed in the same area. This experiment also went well except for the
apparent hitting of a raised mound of sediment by the dredge head which
created noticeable turbidity on the subsurface television monitoring system
located 3.5 m above the sediment surface, immediately over the dredge head.
Results and interpretation of the experiment were sent to the Corvallis
Environmental Research Laboratory in April 1978. They were supplied by Mr.
Hiroshi Suda of the Japanese Ministry of Transport. The United States was
subsequently authorized by that Agency to publish results of the experiment.
They are published exactly as they were received exceot for retyping and
drafting, an occasional spelling correction and standardization concerning
format.
295
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JAPANESE DREDGING DEMONSTRATION PROJECT RESULTS
The results and conclusions of the dredging demonstration at Port
Yokkaichi, Japan are presented on the following pages. They were made avail-
able by Mr. Hiroshi Suda, Director of the Environmental Protection Division of
the Japanese Ministry of Transport. All information on these pages resulted
from work conducted by the Japanese Government. There has been no attempt by
the editors to interpret or evaluate these data. They are published here so
that individual readers may draw their own conclusions.
296
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RESULTS OF THE INVESTIGATION OF TURBIDITY
GENERATED BY DREDGES AT YOKKAICHI PORT
1. Outline of the investigation
This investigation was executed at Yokkaichi Port using two specialized
dredges to gain the quantity of turbidity generated by dredging works. The
outline of the investigation is shown in Figures 1, 2, 3 and 4 and Tables 1
and 2.
Fig. 1 Outline of investigation site
Fig. 2 Trace of float
Fig. 3 Dredged materials (Particle size accumulation curve)
Fig. 4 Arrangements of measuring points
Table 1 Meteorological observations
Table 2 Dredged materials (Grain size distribution)
2. Measuring items
Item Points Period Method
(water quality)
turbidity
concentration
of SS
(bottom sediment)
grain size
distribution
St. 1,
St. 2 (3 layers),
St. 3, St. 4
St. 1, St. 2,
St. 3, St. 4,
suction head
(2 points)
dredging site
Approx.
100 minutes
continuously
every 5 minutes
before dredging
turbidity meter
pump sampling
(marine phenomenon)
velocity of St. 2
tidal current
ditto
Approx.
100 minutes
continuously
every ten
minutes
propeller
current meter
float
(other)
volume of
dredged materials
position of
suction head
during
dredging
during
dredging
297
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3. Results of Investigation
Concentrations of suspended solids at Stations 1 through 4 and 2 points
around suction head are shown in Tables 1 and 2 respectively, which were meas-
ured through filtration of the sampled water in the laboratory.
On the other hand, time history of turbidity shown in Figures 5. 6. 7 and
8 is gained through converting the continuous records of turbidity level
measured by turbidity meters on boats i ito concentration of suspended solids.
(As there is no conspicuous difference of concentration of suspended solids
between the two cases shown in Tables 3 and 4, time history is shown in one
case here.)
Figure 9 shows the comparison of tie concentration of suspended solids
around the suction head between conventional dredges and specialized ones.
The value of conventional dredges (pump dredge with cutter) shown in
Figure 9 was measured at Yokkaichi Port in 1974 for the same soil as in this
investigation.
Judging from Figure 9, we can conclude that the concentration of sus-
pended solids around the suction head of specialized dredges is very low,
approximately one-tenth that of conventional ones.
298
-------
Dredging Condition
Type of dredger
Conventional
Specialized
Date
Dredge
site
Dredged Sand
material Silt
(wt.%) Clay
Water depth (m)
Test No. 12 #
Moving distance of (1)
spud with one swing (m)
Swing rate (m/min) (2)
Depth of cut (in) (3)
Discharge pipe
diameter = D (m)
RD2/4 (m2) (4)
Percentage of mud (5)
content (%)
Flow velocity in (6)
discharge pipe (m/sec)
Apparant excavated (7)
volume (m3/h)
(1)(2)(3).60
Virtual dredge (8)
production (m3/h)
(4)(5)(6). 3600/100
Mixture flow rate (9)
(m3/h)
(4)(6).3600
1974.11. 1978.3.
6-22 8-9
near North wharf near Asahi breakwater
in Yokkaichi port water in Yokkaichi port
9 11
58 41
33 48
12 14
2C1-1 2C1-2 CHOSA1 CHOSA2
2.03 2.07 2.5 2.5
7.0 7.2 5.1 5.0
1.7 1.9 0.53 0.49
0.61 0.61 0.56 0.45
0.292 0.292 0.246 0.159
21.6 29.1
4.91 4.66 1.41 3.14
1,149 1,699 405 368
1,115 1,426 324* 294*
5,163 4,900 1,251 1,800
# : Test number shown in Figure 9.
* : Value of (7) x 0.8, where 0.8 is empirical constant.
299
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TABLE 1. THE RECORD OF METEOROLOGICAL OBSERVATIONS
Dredging Time
Wind
^_ Wave Height Tidal Current
Date Test No. (hr-min) direction(m/s) (cm) direction (m/s) Weather
3/8 CHOSA-1 8:30-9:50 W
3/9 CHOSA-2 9:00-10:20 NW
1.0
1.0
10
10-20
<0.05 Clear
<0.05 Clear
TABLE 2. DREDGED MATERIALS
Gravel Sand Silt
0.4 11.4 41.2
/•*1 \.ij_ 60
C U ' Uc D10
(*2) : U = (D30)2
D10XD60
Clay (*1) (*2) Name
c c
48.0 11.88 0.64 Silty Clay
300
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TABLE 3. AN ANALYSIS TABLE OF SUSPENDED SOLIDS
CHOSA-1
U)
o
SS (mg/1)
S2
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
SI1
2
4
10
76
6
6
8
6
9
2
2
2
4
5
4
4
8
4
S2
10
8
9
8
10
4
9
6
7
3
5
4
4
4
6
7
8
7
S3
8
6
8
5
9
5
6
9
7
7
6
15
18
4
6
3
6
7
center3
6
6
2
4
4
5
4
7
2
5
5
2
5
7
2
4
4
4
right
4
4
2
8
19
11
4
6
3
7
7
5
8
15
9
6
8
8
time
8 32 30
8 35
8 37 30
8 42 30
8 45
8 47 30
8 53
8 55 30
8 58
9 24 30
9 27
9 29 30
9 35
9 37 30
9 40
9 46
9 48 30
9 51
SS (mg/1)
S4
4
6
2
8
2
2
2
1
1
2
14
4
5
3
5
time
8 20
8 25
8 30
8 35
8 40
8 45
8 50
8 55
9 00
9 05
9 10
9 15
9 20
9 25
9 30
1 SI ~ S4 = the observing boat
2 S = dredge.
3 "
Center" and "right" = the position of sampling points around suction head.
4 Dredging continued from 8:30 to 9:50.
-------
TABLE 4. AN ANALYSIS TABLE OF SUSPENDED SOLIDS
CHOSA-2
CO
o
ro
SS (mg/1)
S2
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
SI1
2
2
2
2
5
6
6
6
4
8
21
13
6
12
6
7
9
8
S2
3
4
4
3
4
4
8
2
1
1
8
15
9
6
9
8
8
5
S3
4
4
4
4
4
2
8
4
3
1
3
1
1
2
2
5
2
5
center3
4
7
6
4
8
6
15
6
10
2
5
2
8
8
9
3
3
9
right
5
7
4
4
4
10
4
24
13
9
4
8
18
12
12
10
3
8
time
9 02 30
9 05
9 07 30
9 12
9 14 30
9 17
9 21 30
9 24
9 26 30
9 53
9 56
9 58 30
10 04
10 06 30
10 09
10 15
10 17 30
10 20
SS (mg/1)
S4
5
7
5
4
4
2
2
0
1
2
0
2
2
2
2
time
8 50
8 55
9 00
9 05
9 10
9 15
9 20
9 25
9 30
9 35
9 40
9 45
9 50
9 55
10 00
1 SI ~ S4 = the observing boat
2 S = dredge.
3 "Center" and "Right" = the position of sampling points around suction head.
4 Dredging continued from 9:00 to 10:20
-------
CO
o
CO
ASASHI BREAKWATER
\
flA
\
Figure 1. Investigation site
-------
0
20
40m
3/8
GJ
o
OBSERVING BOAT
•si
DREDGING AREA
OBSERVING BOAT
•si
(Trace of Float every Ten Minutes)
3/9
STARTING POINT OF THE FLOAT
OBSERVING BOAT
S3
Figure 2. Investigation of tidal flow by float.
-------
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en
100
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UJ
cc 60
UJ
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1 T
I I
• 3/8 CHOSA-I
o 3/9 CHOSA-2
I I
l I
I l
10
r2
10
-l
5 \0(
5 10
PARTICLE SIZE (MM)
Figure 3. Particle size accumulation curve.
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ASASHI BREAKWATER /
J /
•
OBSERVING BOAT
STARBOARD SWING WIRE
SWING
RANGE
50 M
SPUDS
—4-
OWN) S<
(DOWN) S4
^30M
TIDAL '
"CURRENT
PORT SWING WIRE
Horizontal arrangement of observing boat.
WATER SURFACE S1
S2
S3
S4
S5
II-II.5
— I
I
!l,5M
I.5M
©!•
I,5M| ~J7,5M
Ci i
• o.
"TDREDGEDJBOT
i i ;
2.6M I
^
©TURBIDITY METER ©SAMPLING MOUTH
Figure 4. Device arrangements for turbidity measurements.
306
-------
16
1*12
ro
ro" 8
0
1 \ I r
I I i I I
I I I
ST1-
I I I I
Figure 5.
20 40 60 80
TIME (MIN)
Time history of suspended solids
IOO
120
12
8
rq
ro
1 1 1 1
\ i r
SI2_
Lower
Middle
Upper _
i I i i i i i i i i
0
20
40 60 80
TIME (MIN)
100 120
Figure 6. Time history of suspended solids
307
-------
I I I I I I I I I I I
12
8
ro
r6
I I I I I I i I I i L
0
20
40 60 80
TIME (MIN.)
100 120
Figure 7. Time history of suspended solids
III
0
Figure 8.
20 40 60 80
TIME (MIN.)
Time history of suspended solids.
308
100
-------
CO
CD
o
.c
t
LU
Q
WATER
0.5
0,4
0.3
0,2
O.I
0
1 1 1 1 I 4 1 1 1 | I ||
PUMP DREDGE WITH CUTTER
1
Cutter revolution NC= 18 rpm —
Swing speeds V$=6 m/min
Swing direction
" CHOSA-I \
\ ^
1^ CL i \
' 1 *"O 1
CHOSA-4
1 1 1 1 1 1 1
2 4 6 8 10 2 4
AVERAGE
^v/
\ \0\ \
fix
6 8 10
o
•
1 |
2
Left
Right
1 1
4 6
—
—
—
I
8 l<
SUSPENDED SOLIDS SS (mg/l)
Figure 9. Comparison of SS around suction head between conventional
dredges and specialized dredges.
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REFERENCES
Callaway, R. J. and C. Koblinsky. 1977. Transport of pollutants in the
vicinity of Prudhoe Bay, Alaska. Unpublished manuscript. Environmental
Protection Agency, Corvallis Environmental Research Laboratory, Corvallis, OR.
Callaway, R. J., A. M. Teeter, D. W. Borne, and G. R. Ditsworth. 1975.
Preliminary analysis of the dispersion of sewage sludge discharged from
vessels to New York Bight waters. In: Middle Atlantic Continental Shelf and
the New York Bight. M. Grant Gross [ed.] Proceedings of the Symposium Ameri-
can Museum of Natural History, New York City, NY.
Proni, J. R., F. C. Newman, R. L. Sellers and C. Parker. 1976. Acoustic
Tracking of ocean-dumping sewage sludge. Science. 193;1005-1007.
Sato, E. 1977. A method for disposing of waste water at dredged material
reclamation sites. In: Management of Bottom Sediments Containing Toxic
Substances. Spencer A. Peterson and Karen K. Randolph [eds.] Proceedings of
the second U.S./Japan Experts' Meeting, Tokyo, Japan. EPA-600/3-77-083.
Environmental Protection Agency, Corvallis Environmental Research Laboratory,
Corvallis, OR.
310
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
. REPORT NO.
EPA-600/3-78-084
2.
3. RECIPIENT'S ACCESSION NO.
. TITLE AND SUBTITLE
5. REPORT DATE
anagement of Bottom Sediments Containing Toxic
ubstances: Proceedings of the Third U.S.-Japan Experts'
eeting -- November 1977, Easton, Maryland
1Q7R
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
Spencer A. Peterson and Karen K. Randolph, editors
t. PERFORMING ORGANIZATION NAME AND ADDRESS
Environmental Research Laboratory--Corvallis, OR
Office of Research and Development
U.S. Environmental Protection Agency
Corvallis. Oregon
10. PROGRAM ELEMENT NO.
1BA608
11. CONTRACT/GRANT NO.
2. SPONSORING AGENCY NAME AND ADDRESS
same
13. TYPE OF REPORT AND PERIOD COVERED
inhouse
14. SPONSORING AGENCY CODE
EPA/600/02
5. SUPPLEMENTARY NOTES
Proceedings of the Second U.S.- Japan Experts' meeting
on Bottom Sediments is
EPA-600/3-77-083
6. ABSTRACT
The United States-Ministerial Agreement of May 1974 provided for the exchange of
environmental information in several areas of mutual concern. This report is the
compilation of papers presented at the Third U.S.-Japan Experts' Meeting on the
Management of Bottom Sediments Containing Toxic Substances, one of the 10 identified
problem areas.
The first meeting was held in Corvallis, Oregon, in November 1975. The second
meeting was hosted by the Japanese Government in October 1976. The third meeting
(at which these papers were presented) was held in November 1977 in Easton, Maryland.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
COSATI Field/Group
water reclamation
sanitary engineering
contaminants
water pollution
ocean bottom sediments
freshwater bottom sediments
toxic sediments
mercury, PCB contamina-
tion of sediments
water pollution
pollution elimination/
control
dredging
06/F
08/A,C,J,H
13/B.J,
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report I
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (Rev. 4-77)
311
U.S. GOVERNMENT PRINTING OFFICE: 1978—b
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