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WORLD BANK TECHNICAL PAPER NUMBER 126
TRANSPORT AND THE ENVIRONMENT SERIES
Environmental Considerations for Port and Harbor Developments
John D. Davis, Scott Ma&night, IMO Staff, and Others
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WORLD BANK TECHNICAL PAPER NUMBER 126
TRANSPORT AND THE ENVIRONMENT SERIES
Environmental Considerations for Port and Harbor Developments
John D. Davis, Scott Ma&night, IMO Staff, and Others
The World Bank Washington, D.C.
The basic structure and contents of this Technical Paper have been put together by John D. Davis, Ph.D., who is currently a private consultant specializing in environmental sciences, engineering impacts, environmental programming and planning, and providing services to a wide range of clients including government agencies, investigatory groups and legal advisors. He is the author of a number of papers and publications, many of which deal with the maritime environment.
The Annex to this paper which specifically deals with dredged materials disposal is by Scott D. MacKnight, Ph.D., OceanChem Group. Dr. MacKnight is a private consultant specializing in environmental sciences with special reference to the environmental aspects of dredging and dredged material disposal to a wide range of clients including government agencies and private clients. He is the author of a number of papers and publications dealing with contaminants in the maritime environment. Both authors prepared this paper while consultants to the Transportation Division, Infrastructure and Urban Development Department of the World Bank.
Considerable input has also been made by the Marine Environment Division of the International Maritime Organization (IMO) and in particular by Terene M. Hayes, Manfred Nauke, Bin Okamura, Jon Wonham and John H. Karau of that division. The Bank is extremely grateful to IMO for their agreement to work closely with the World Bank on this paper. The Bank’s appreciation is acknowledged to Konstantin I. Voskresensky, Director, Marine Environment Division, for IMO’s cooperation, enthusiastic support and professional input.
John Ft. Lethbridge, Ports Advisor, World Bank, was responsible for the preparation of the paper, wrote the introduction and other sections, and incorporated where appropriate the many comments and suggestions received from a wide range of professionals both outside and inside the World Bank.
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Environmental Considerations for Port and Harbor Development
TABLE OF CONTENTS
PARTl- SUMMARY OF MAJOR ENVIRONMENTAL ISSUES
A. Introduction
B. Common Environmental Problems in Port and Harbor Development
Water-Related Impacts Impacts caused by dredging Construction of piers, breakwaters and other structures Ship discharges - oily ballast; bilge water; sewage Spills: detection and clean-up of spills
Land-Related Impacts Waterfront Industries Run-off into wetlands Relocation; Lost land use; Involuntary resettlement Dust and other airborne emissions Traffic burdens Waterfront drainage
Air-Related Impacts Fugitive emissions
Hazardous Materials/Cargoes
Socio-Cultural Impacts
Existing Port Regulations
C. World Bank Policy and Recommended Project Preparation and Implementation Procedures
Identification Impacts Resulting From The Construction Activity Operational impacts Preparation Appraisal Loan Negotiation Implementation Environmental Post-Audits
4 4
5
5
5
6
D. Conclusion 9
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PART II - CHECK LIST 11
1. Water-Related Impacts
1.1 Impacts caused by dredging 1.2 Impacts of dredged material disposal 1.3 Construction of piers, breakwaters and
other waterside structures 1.4 Alteration of harbor/port ship traffic patterns 1.5 Ship discharges--oily ballast; bilge water;
sewage 1.6 Spills: detection and clean-up of spills 1.7 Waterfront industry discharges--sanitary
and non-sanitary
2. Land-Related Impacts
2.1 Excavation for fill 2.2 Wetland damage and filling 2.3 Loss of usable uplands to expanding
waterfront/industrial areas 2.4 Noise from ports and harborside industry 2.5 Effects of dust and other airborne emissions 2.6 Traffic burden projections 2.7 Handling and disposal of solid shore generated
wastes 2.8 Runoff from raw material storage 2.9 Waterfront drainage 2.10 Industrial liquid wastes not discharged to harbor
3. Air-Related Impacts 18
3.1 Important background information 18 3.2 Fugitive emissions 18 3.3 Gases, smoke, and fumes 18
4. Hazardous Materials/Cargoes 18
4.1 Categories--gases, liquids, solids 18
5. Socio-Cultural Impacts
6. Review of existing and proposed regulations affecting the proposed port or harbor development and its construction
7. Need for construction or facility operation environmental monitoring
11
11 11
12 12
13 13
14
15
15 15
16 16 16 16
17 17 17 17
19
19
19
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PART III - TECHNICAL SECTION 20
Part III is the main text of the Technical Paper. It provides the user with guidance on how to approach the environmental problems issues and impacts that have been identified from the Check List review of the proposed development. The order of presentation is the same as the Check List.
1. Water-Related Impacts
1.1 Impacts caused by dredging 1.2 Impacts of dredged material disposal 1.3 Construction of piers, breakwaters, other
waterside structures 1.4 Alteration of harbor/port ship traffic patterns 1.5 Ship discharges--oily ballast; bilge water; sewage 1.6 Spills: detection and clean-up of spills 1.7 Waterfront industry discharges--sanitary and
non-sanitary
2. Land-Related Impacts
2.1 Excavation for fill 2.2 Wetland damage and filling 2.3 Loss of usable uplands to expanding water-
front/industrial areas 2.4 Noise from ports and harborside industry 2.5 Effects of dust and other airborne emissions 2.6 Traffic burden projections 2.7 Handling and disposal of solid shore generated
wastes 2.8 Runoff from raw material storage 2.9 Waterfront drainage 2.10 Industrial liquid wastes not discharged to harbor
3. Air-Related Impacts
3.1 Important background information 3.2 Fugitive emissions 3.3 Gases, Smoke and Fumes
4. Hazardous Materials/Cargoes
4.1 Categories--gases, liquids, solids
5. Socio-Cultural Impacts
6. Review of Existing and Proposed Regulations Affecting the Project and its Construction
7. Need for Construction or Facility Operation Environ- mental Monitoring
20
20 21
22 23 24 28
29
33
33 34
36 36 37 37
38 39 40 40
41
41 42 42
43
43
43
44
44
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PART IV - BIBLIOGRAPHY
Annex I - The Environmentally Sound Disposal of Dredged Materials
Attachment I London Dumping Convention - Annexes I, II, & III
Attachment II Guidelines for Application of the Annexes to the Dispoal of Dredged Materials
45
47
PART I - SUMMARY OF MAJOR ENVIRONMENTAL ISSUES
A. Introduction
The World Bank's experience has shown that port, harbor and similar maritime developments can have serious implications for many aspects of the environment. Because of the nature of maritime works, a wide range of very different environmental activities are likely to be affected in one way or another, many of these permanently. This Technical Paper has been prepared with the object of providing assistance to World Bank staff engaged in the appraisal of lending operations associated with port and harbor development and also to help the management and staff of ports and port authorities in less developed countries (LDC's) appreciate the full range of topics to be considered in dealing with environmental aspects of their ports and harbors.
The Bank's experience during the past decade has demonstrated the need for early attention to the environmental dimensions of project work. Developments require sound management of natural resources, particularly renewable resources, and systematic attention to their impact on the environment. Renewable resources include living resources (plants, animals and fishes) and other natural resources (particularly soils and water) that create or sustain life and that are self-renewing if not mismanaged. The Bank has also found that:
- environmental damage can be prevented or greatly reduced at a cost which is financially acceptable to its borrowers.
- environmental protection measures can often be shown to have economic benefits that exceed their economic costs. In other cases qualitative or not readily quantified benefits, particularly from avoidance of irreversible effects, may readily justify the cost of protection. In most cases, preventive measures give more effective protection and at less cost than later remedial measures.
Port and harbor development normally create local environmental problems, although those developments associated with estuaries or rivers may result in regional effects. The type of local problem that may occur include: accelerated erosion or acretion; the loss of animal, plant or marine species or the natural habitats on which they depend; the contamina- tion of a fishery through uncontrolled run-off or waste disposal; occupa- tional and health hazards; salt wedge intrusion; pollution from ship spills or discharges; the disposal of polluted dredged materials from maintenance dredging activities, etc. The Bank must endeavor to ensure that the economic development which it is promoting does 510t- ('xc b,:rbl! I J!- capacities of the environment.
This Technical Paper presents the more common environmental problems that are likley to be encountered in the development of ports and harbors and follows with a comprehensive "check list" of environmental
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issues which can be used by Bank Staff or the management of ports to ensure that they have considered all of the possible issues that might affect their particular project . The main text of the paper then provides additional information and guidance on how to proceed for each of the items in the check list. The paper is not fully comprehensive and it will be necessary to refer to authoritative sources for assistance in many instances. Where possible these sources have been defined.
Because of the worldwide concern for the environmentally sound disposal of polluted materials resulting from dredging operations and the need for solutions to the disposal problem, an Annex is included which specifically addresses the nature of the problem, the issues, the international regulatory framework and the technical solutions currently available and being researched.
0 _Common Environmental Problems in Port and Harbor Development
This Technical Paper is intended to bring to the attention of the reader the various aspects of port, harbor and maritime development that could result in an impact on the environment. Clearly, for any particular project , only some of these topics need to be considered. Also, the impacts that have to be considered in a port project in the Seychelles will be quite different from those in a port project in Turkey. Even for projects in adjacent countries the impacts are likely to be very different as a consequence of the type of development proposed, the cargo being handled, the geography, the hydrology, the relative urban and industrial locations, and numerous other factors.
There are, however, some environmental aspects of port and harbor development which seem to occur with greater frequency than others and these are discussed below.
Water-Related Impacts
Impacts caused by dredging (l.l)l A common problem, particularly in tropical countries is the dispersal and settlement of resuspended sediments on sensitive aquatic ecosystems (e.g. coral reefs) as a consequence of a nearby dredging operation. Concern may be expressed that the reef structure will be permanently damaged. This is not often the case, however, and there are many examples of coral reefs where, soon after the completion of the dredging activities, examination showed that the reef was quite undamaged. In the case of regular maintenance dredging type of work the consequences may not be the same and would need to be carefully investigated. Serious problems may result from deepening operations in an estuary which permits the salt wedge intrusion to travel higher upstream than previously and thus changing the regime of bankside wetlands as well as the river. Similarly, deepening can result in increased shoreline wave action with consequent accelerated erosion and other problems.
FThe numbers shown here refer to the paragraph numbers used in the main text of this technical paper.
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Construction of piers, breakwaters and other structures (1.3) Breakwaters, groynes, training walls and similar structures provide the biggest problems. Particularly erosion and accretion effects where such structures are built in a zone of high littoral sediment transport. In some instances, the possibility of providing sediment by-passing arrangements may be necessary to preserve downdrift coastlines and structures. Inlet type structures also need particular care in design to avoid excessively high tidal flow velocities and the associated risks for small craft navigation. The creation of a sheltered basin through the use of breakwaters can often result in difficult sea conditions within the basin as a consequence of wave reflection and resonance resulting in a number of problems which can be mitigated through modelling and the construction of spending beaches and non-reflective quaywalls.
Ship discharges - oily ballast; bilge water; sewage. (1.5) The International Maritime Organisation (IMO) is charged with the prevention and control of pollution of the marine environment from ships and has recently adopted a series of conventions which require ports to provide facilities to receive wastes from vessels using the port. Whilst essential, these facilities are relatively expensive to provide and, in some cases for LDC's, the maintenance is onerous because of the difficulties and costs involved in the ultimate disposal of the wastes. This can be quite a burden for an LDC port and projects may well need to include these facilities as a component.
The effects of anti-fouling paints on bottom dwelling marine organisms - particularly clams and oysters - when the depth is relatively shallow and there are a number of craft moored in one location can be severe. A number of countries have banned the use of paints containing tributyl-tin for this reason. Where shallow small craft harbors exist in close proximity to beds of such organisms the situation should be reviewed carefully. Floating dry-dock operations need special attention in this respect.
Spills: detection and clean-up of spills (1.6) The avoidance of spills of all kinds is a key requirement. Many LDC ports are currently extremely lax in enforcing regulations and controlling vessels - both visiting ships and their own local and port craft. It is a question of discipline and strong control by the harbor master. The provision of cleaning/skimming equipment and specialised oil spill response equipment is essential together with a trained crew to operate it. Important spills in LDC ports that require strict attention is the spillage of grains on the sea floor adjacent to quays and wind blown dusts from dry bulk cargoes such as bauxite, phosphates, sulphur and coal.
Land-Related Impacts
Waterfront Industries There will be many instances where the proposed port development is centered on the establishment of an industry which needs port or waterfront lands. Examples are steel plants, aluminium smelters, papermills, and etc. Although the port component of the industry is a relatively small part of the complex, the Bank port engineer and port
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authority must consider all of the environmental impacts of the industry (even though the prime responsibility rests with the industry sponsors) and be satisfied that the environmental issues are being appropriately addressed.
Run-off into wetlands (2.2.4) In many ports the run-off from open storage areas leads to adjacent wetlands resulting in the area becoming degraded and acting as a sink for contaminants. Better control of the quality of the run-off is needed in most cases.
Relocation; lost land use; involuntary resettlement (2.3.2) There are many instances where port expansion results in the need to relocate an existing village, or a fishermen’s beach or agricultural lands. An acceptable resettlement plan will have to be made an integral part of the project. Socio-economic studies are started as soon as project design begins since resettlement can be more complicated than the project engineering and very time consuming. The resettlement costs can reach a very high proportion of the project costs. The Bank now has systematic and detailed policy designed to ensure successful resettlement. One of the criteria is that the displaced people shall be preferably better off and certainly no worse off after relocation.
Dust and other airborne emissions (2.5) Wind blown dust from stockpiles of bulk materials is a major problem in some ports and needs to be properly controlled using modern methods and technology.
Traffic burdens (2.6) Because of the location of many LDC ports very difficult issues arise over the increased road traffic to and from port areas. This is a particularly acute problem where the main arteries to and from the port pass through heavily built up and congested urban areas and there is little or no way to provide alternative routes - the only solution may be to relocate the port.
Waterfront drainage (2.9) This is a major consideration for almost every existing port. The traditional design of quay has included slopes on the hard- standings and aprons behind the quay to permit rainfall to discharge over the quay wall into the port or harbor waters. As a consequence, anything spilled on the ports working surface eventually finds its way into the sea. Spillages and breakages will always occur, even in the best managed ports, and, with the advent of cargo handling equipment with extensive hydraulic systems, spills of hydraulic oil from burst hoses can be frequent . Thus it is prudent to design the quay structure so that stormwater can be collected and allowed to pass through a separator before being discharged and all new structures should be designed in this way. The cost of converting existing waterfront structure may be prohibitive and would probably involve the installation of sizeable pumping facilities - especially in tropical countries with high rainfall intensities.
Air-Related Impacts
Fugitive emissions (3.2) Wind blown dust can be a major problem. Coal dust, bauxite, cereals, phosphates, are typical materials being handled in
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bulk in LDC ports and where measures to control dust dispersion are required. Fortunately the technology and techniques for control are available and in many instances the costs are not excessive or prohibitive.
Hazardous materials/cargoes (4)
The risks and dangers associated with the transit of hazardous materials through LDC ports are frequently ignored. It is an area of major concern and Bank staff and port authorities should ensure that measures are introduced to monitor and control the passage of such goods through the port. Typical examples of cargoes that are often treated just as normal types of cargo are pesticides in drums, corrosive chemicals in jars or drums, minor explosives, and cylinders of pressurized gases.
Socio-Cultural Impacts (5)
Port development often has social, political and cultural impacts. Restrictive labor practices, religious practices, and social behavior patterns become serious problems when introducing new technology such as pre-slung cargo techniques, container terminals (with 24 hour working) and Ro-Ro vessels. Extreme care and continuous dialogues with the various parties involved will be necessary before some of the newer technologies can be successfully introduced. Increased productivity is a common goal, but there are many obstacles associated with working hours, gang composition, the increased use of the private sector, the use of electronic data processing and the introduction of multiple shift working. Labour redundancy is a major problem to be addressed in almost every port in the world. The Bank has studied this problem in depth and the experiences of other ports has been compiled.
ExiStinQ Port Regulations (6)
Port management is generally charged with the provision, operation, maintenance, improvement and regulation of the facilities. The regulatory aspects cover many activities some of which result in environmental impacts. Typical of these are concerned with safety, health, handling of hazardous cargoes, working conditions, avoidance and control of spillages, housekeeping and waste disposal. It is essential that the existing port regulations be reviewed through the use of the check list in this paper to identify any possible conflict or omission. The most common problems in LDC ports are those associated with health and particularly safety. For instance, it is common to see port workers handling copper ingots from lighters to shore and ship wearing no shoes, hard hats or adequate clothing. Accidents may be infrequent, but this type of practice should not be allowed to continue. Adequate safety regulations should be implemented in all ports - regardless of their location.
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C. World Bank Policy and Recommended Project Preparation and Implementation Procedures
World Bank policy emphasizes the need for prudence when assessing environmental effects, especially when these are irreversible. Prevention is preferable and generally less costly than remedial actions, which may not always be possible. Some environmental effects take a long time before they become identifiable. Therefore, the Bank considers the environmental aspects of projects in a longer time frame, 25-50 years and more.
Rather than adopting environmental standards, the Bank's approach is tailored to local circumstances and respects the vast differences among its LDC members. The practice is to consider each project unique with respect to its total setting and to the abilities of the port and other national authorities concerned with the environment. This Technical Paper is considered to be the forerunner to a World Bank set of environmental guidelines on port and harbor development which would be distilled from a wide range of accepted international recommendations and standards. Bank guidelines have been published for other sectors and, where they exist, they suggest acceptable ranges to be followed in Bank operations, unless the borrowing country's standards are more strict - in which case the coun- try's standards are adopted. The principle2 behind these guidelines may be summarized as follows. The Bank:
- will not finance projects that cause severe or irreversible environmental deterioration without mitigatory measures accept- able to the Bank (for example, reclamation of extensive wetlands accompanied by the diversion of a river outlet for the creation of port areas).
- will not finance projects that unduly compromise the public's health and safety (for example, the handling of certain chemical products from ship/shore using labour intensive methods).
- will not finance projects that displace people or seriously disadvantage certain vulnerable groups without taking mitigatory measures acceptable to the Bank (for example, the displacement of a beach used as a base of operations by traditional fishermen to make way for port expansion).
- will not finance projects that contravene any international environmental agreement to which the member country concerned is a party (for example, the IMO MARPOL Conventions concerning the need to provide shore facilities for the reception of wastes from vessels).
- will not finance a project that could significantly harm the environment of a neighboring country without the consent of that country (examples are, causing serious erosion problems to a neighboring country's coastline as a consequence of breakwater
i?/ Source: Environmental Requirements of the World Bank, 1985.
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construction, or, changing the regime of a river which serves two or more countries).
- endeavors to ensure that projects with unavoidable adverse consequences for the environment are sited in areas where the environmental damage is minimised, even at somewhat greater costs (for example, the relocation of port facilities to avoid complex urban and land congestion problems even though this implies more costly communications and construction costs).
Projects with unavoidable adverse effects on the environment should contain an adequate compensatory component. This type of compensation has been institutionalised in port projects where people are involuntarily resettled. In other situations - as in a project where an existing small craft and fishing vessel anchorage has been absorbed into the port's navigable areas - a compensatory component would set aside or create an alternative anchorage with protection and qualities similar to the original.
The Bank's environmental experience has shown that it is fundamen- tal to the good design of development projects and feasible to incorporate suitable measures to protect the environment. A pragmatic approach, as insisted on by the Bank, is the key. Each project being regarded as unique within its environmental setting. The environmental work thus becomes a continuous process during the preparation and implementation of the project and not a discreet or "add-on" component. Environmental criteria should be factored into the planning and design decisions together with economic and engineering criteria from the very earliest identification stage of the project, but, may be added or modified in varying degrees through prepara- tion, appraisal, negotiations and supervision.
Identification: Port projects being proposed or considered for Bank financing must be reviewed as early as possible to identify possible signi- ficant environmental effects. This review would determine, first, what investigations, studies, surveys, etc., are needed to ensure that appropri- ate measures will prevent or mitigate any serious adverse effects attribut- able to the project; and second, whether the project's environmental costs or risks can be avoided entirely. When they cannot be avoided, the evalua- tion of the project should include an impact balance sheet to enable the adverse environmental impacts to be weighed against the quantified benefits and costs used in the usual benefit cost analysis.
Although the port authority or borrower is responsible for taking the action that is needed, more than likely, in many cases it will be the Bank's port engineer who will have an important role in guiding the borrower's staff and management on how to proceed. The engineer can request assistance from the Bank's environmental staff or other sources to help him in this task. (Eventually, the Bank's staff will have to be satisfied that the borrower has taken appropriate action.) The main objective of this Technical Paper is to provide the Port Engineer, or other Bank staff, with a clear guide of the full scope of port and harbor environmental issues which may need to be considered. By going through the
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Check List of the Paper it will become apparent which of the items will need to be considered in the context of the project being identified.
The environmental impacts likely to result from the project can be classified as follows:
- Impacts resulting from the construction activity These commence usually as soon as construction starts and cease soon after the end of the construction period. However, impacts may persist beyond the construction period especially if they result from unnecessarily disruptive or careless engineering/construction practices.
- Operational impacts - there are three categories i) those that are losses or degradation of the environment
and result from some alteration (frequently irreversible) attributable to the project;
ii) those that are not necessarily irreversible but persist as long as the project continues to operate and the related activities continue; and,
iii)those resulting from the decommissioning of redundant facilities coupled with the need to rehabilitate the affected areas to an acceptable environmental standard.
Preparation: The borrower is responsible for project preparation. The Bank may assist in carrying out the necessary environmental investigations, studies or surveys. The Bank assistance could take the form of help in preparing TOR's, financing the costs of the work, and in reviewing the draft final reports. In some cases this work can be undertaken concurrent- ly with, and as part of, the project feasibility studies. Following their completion and based on the results and recommendations, the detailed engi- neering for the project should then incorporate measures designed to avoid or mitigate serious environmental risks or to enhance environmental bene- fits. In providing the TOR for the consultants or others responsible for the detailed engineering, it may be appropriate to refer to the Check List to avoid possible omissions and to ensure a common approach. It is poss- ible that further need for additional environmental studies could be identified at this stage which need to be completed prior to appraisal or could be delayed until the project is effective.
In marine environmental impacts, there is very often the need for monitoring of water quality and the sea floor by marine biologists and other specialists. This monitoring should be commenced during the prepara- tion stage and continued in many cases long after the completion of the project. This type of monitoring is best carried out by local organiza- tions and in many countries the marine zoology or biology departments of the university are both keen and appropriate to carry out this type of work. If necessary their activities could be funded through the project.
Appraisal: As part of the appraisal process, the Bank assesses the envi- ronmental findings, evaluates the future magnitude and timing of adverse effects, and assesses whether the preventive, mitigatory or remedial mea-
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sures proposed will be adequate. The Staff Appraisal Report should describe the environmental measures being provided and the extent of any further environmental studies, surveys or monitoring that are required under the project. It will be on the basis of the appraisal that agreement is reached on environmental measures to be incorporated into the detailed engineering and operation of the project.
Loan Negotiation: Preferably important project issues should be resolved with the borrower prior to the negotiations. Where necessary, however, environmental requirements will be discussed at negotiations between the Bank and the borrower, and the loan agreement may contain covenants or other provisions concerned with environmental aspects of the project. Since the Bank seeks to ensure that the project's construction impact and operational impacts will not unnecessarily harm the environment, satisfac- tory evidence to this effect may be required as a condition for loan effec- tiveness or disbursement. Typical provisions might include the need for regular hydrographic surveys to record accretion or erosion effects; regu- lar monitoring of adjacent coral reefs or of sea water quality; legislation concerning resettlement of displaced people; the provision of wastewater treatment facilities; etc.
Implementation: Environmental measures are frequently implemented during the construction stage of a port or harbor project. The Bank's staff, during the course of supervision missions, should routinely review environ- mental aspects with the borrower and must ensure that the measures pre- viously agreed upon are adequate and being responsably administered. It is possible that during the implementation period and at the start up of ope- rations that additional or modified measures will be needed. These should be discussed with the borrower, recorded and arrangements made for their implementation. A typical example of this type of action could result from the monitoring of the sea floor showing the effects of a breakwater con- structed at the commencement of the project is giving rise to unexpected environmental effects which require further study or additional works.
Environmental Post-Audits: The Project Completion Report (PCR) will des- cribe the results of the environmental measures provided in the project and will comment on their appropriateness, costs, adequacy, and administration as well as any problems that arose or changes that were made during the implementation of the project and the start up of new operations. On the basis of the PCR the Bank's Operations Evaluation Department identifies projects which have significant environmental issues to be audited. Such PCR's/audits provide a basis for assessing at least the shorter-term efficacy of the environmental measures and thereby provide lessons to be learned for future projects with similar impacts.
D. Conclusion
The World Bank attaches great importance to environmental aspects of development projects. In the case of port and harbor development, ports and port authorities, consulting firms and Bank port engineers and other staff are expected to provide effective and thorough environmental input into the project concept, preparation, detailed engineering, construction
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and operation. This implies the need for adequate environmental units within each of the bodies or agencies responsible for the project. Where such units do not exist then outside expertise will be required in many instances. The use of this Technical Paper with its accompanying Check List is aimed directly at helping those responsible for the project to recognize the very wide range of environmental impacts that can result from port and harbor development. It is unlikely that every aspect will be involved in any one project. It is for the Bank's staff and the staff of the borrower to decide from a review of the Check List which activities will need to be investigated.
In some countries, in order to comply with existing legislation, environmental impact statements will have to be prepared for port and harbor development projects. The preparation of such a statement should also address, the Bank's concerns about the impacts and the mitigatory and compensatory measures to be implemented under a Bank financial project.
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PART II - CHECK LIST
Note to users: One of the principal objectives of this paper is to provide those engaged in port and harbor development with as complete a listing as possible of the many and varied environmental impacts that should be considered. To help in using the paper we have included a small box [ ] against each paragraph which users can check as they go through the paper to note their having considered this particular aspect for the project under preparation.
[ 1 l-0
1 1 l-1
[ ] 1.1.1
[ ] 1.1.2
[ ] 1.1.3
[ ] 1.1.4
[ ] 1.1.5
[ ] 1.1.6
1 1 1.2
[ ] 1.2.1
WATER-RELATED IMPACTS.
Impacts caused by dredging.
Dispersal and settlement of resuspended sediments: Toxic, harmful substances in water column. Reduced available oxygen, sunlight penetration. Smothering bottom biota. Silt curtains to restrict dispersal. Relative impact of dredging methods. Knowledge of tidal and river flows.
Effects of blasting: Compression effects. Indirect effects on fisheries. Damage to shorezone and bulkhead structures.
Results of altered bathymetry: Influence on tidal and river flows. Altered salt wedge intru- sion. Accelerated natural sediment deposition. Attraction of desirable or undesirable fisheries. Altered bottom biota.
Effects of changing shoreline configuration: Change in current patterns. Shorezone and beach erosion. Accel- erated sediment deposition--shoaling.
Loss of bottom habitat, shellfisheries, fishery food resources: Exposed subsurface materials unconducive to recolonization. Lost attachment potential for aquatic biota. Current pattern changes.
Altered groundwater flows: Salt water intrusion. Accelerated groundwater flow to estuary. Undermining of land-edge sediments. Saltwater intrusion to potable water supplies.
Impacts of dredged material disposal
Selection of appropriate disposal site: Disposal on land. Disposal in water. Desired character of dis- posal areas. Methods of dredging and dredged material transfer and related disposal impacts.
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[ ] 1.2.2 Unique Characteristics of Dredged Material
[ ] 1.2.3 Disposal Methods
[ ] 1.2.4 Disposal on land: Drainage. Loss of vegetation. Disposal of contaminants (toxics). Slumping. Revegetation. Aquifer contamination. Leaching of salt, etc.
[ ] 1.2.5 Disposal in water--harbor/river or at sea: Dredged material transport and dumping methods. Loss of bottom biota. Biological recolonization rates. Potential or require- ments for capping. Alteration of current patterns. Accelerated shoaling. Use of artificial islands.
[ 1 1.3 Construction of piers, breakwaters and other waterside struc- tures (new or extension/replacement of existing structures):
[ ] 1.3.1 Filling or excavation covers/removes bottom biota and habitat: Shellfisheries. Fishery food resources lost or displaced.
[ ] 1.3.2 New habitats formed by structures (especially pilings and break- waters): Desirable, undesirable species introduced.
[ ] 1.3.3 Filled structures (including breakwaters): Alter currents. Sediment deposition accelerated. Scouring increased. Change required in harbor maintenance dredging practices. New navigation routines. Protection of submerged pipelines.
[ ] 1.3.4 Disturbance from pile driving, other construction activities: Temporarily displace fisheries and other mobile marinelestuarine resources.
[ ] 1.3.5 Dispersal of suspended sediments: Smothering of bottom biota. Reduced light penetration. Displaced fisheries.
[ ] 1.3.6 Piling-supported structures--effects: Shade bottom. Change habitat. Attract desirable or undesirable species. Accelerated sediment deposition. Increased berth main enance dredging. Increased nearby bottom scouring.
[ ] 1.3.7 Release of preservatives from installed wood structures: Prevent borer establishment. Contaminate fisheries. Release heavy metals to surrounding waters.
1 1 1.4 Alteration of harbor/port ship traffic patterns:
[ ] 1.4.1 Changes in channel, anchorage and turning basin locations: Dredging and dredge material disposal. Increased frequency of maintenance dredging. (See Section 1.1).
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[ ] 1.4.2 Relocation of navigation markers, moorings: Assurance of location precision. Designation of channels for arrival/departure traffic.
[ ] 1.4.3 Addition of new channels, anchorages, turning basins requiring improvement dredging. (See Section 1.1.)
[ ] 1.4.4 Improved procedures for vessel traffic control (VTS) systems. Requirements for collision avoidance systems. Radar. Shore- based radar reflectors. LORAN-C, GPS, DECCA, etc. Requirements for ships using facility. Pilotage.
[ ] 1.4.5 Increased provision for vessel handling and servicing: Additional tugs, lighters, service vessels. Vessel repair facilities. Drydocks. Graving Docks.
[ I I.5 Ship discharpes--oily ballast; bilpe water; sewape.
[ ] 1.5.1 Promulgation of regulations controlling cleaning procedures, limitations of release of cargo and machinery space residues: Discharge limitations--examples cited. Need for facilities to receive waste from ships. Means of storage and ultimate disposal of residual wastes.
[ ] 1.5.2 Environmental sensitivity to discharges from ships. Importance to fishery resources. General water quality of rivers, bays, harbors. Effects if requirements not imposed or regulations not enforced.
[ ] 1.5.3 Development of shore facilities for receiving ship generated sewage and garbage waste. Sanitary treatment facilities- -connection to special or municipal systems. Transfer and pumping facilities. Ultimate disposal of these wastes.
[ ] 1.5.4 Effects of antifouling paints: Relation to ships in dock. Ships in repair. Repair and mainte- nance practices allowed, not allowed. Effects on biota in water, fisheries. types of antifoulants--tributyl-tin, copper based. Vessels berthed in shallow water.
1 I 1.6 Spills: detection and clean-up of spills.
[ ] 1.6.1 Types of Spills: Oils. Lubricants. Hydraulic oils. Fuels. Liquid and solid chemi- cals. Behavior in water. Likely causes of spills. Frequent spill sources--equipment, faulty practices.
[ ] 1.6.2 Resources at risk: Identify areas subject to spills. Aquatic resources most likely in jeopardy: Spill-prone areas. Shellfish resources. Fishery resources. Aquaculture operations.
[ ] 1.6.3
[ ] 1.6.4
[ ] 1.6.5
[ 1 1.7
[ ] 1.7.1
[ ] 1.7.1.1
[ ] 1.7.2
[ ] 1.7.2.1
[ ] 1.7.2.2
[ ] 1.7.2.3
[ ] 1.7.2.4
[ ] 1.7.2.5
[ ] 1.7.3
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Spill clean-up measures: Regulations. Clean-up equipment available, to be added. Spill retention measures--equipment, emergency procedures. Spill detection routines.
Dry cargo releases: Fugitive emissions. Dust control. Enclosed loading and unloading systems. Smoke density and effects.
See also hazardous cargoes.
Waterfront industry discharges--sanitary and non-sanitary.
Sanitary wastes: Sources. Volumes. Special contaminants. Produced by project. Not produced by project.
Sanitary treatment facilities: Existing. Planned. Proposed. Capacity of each. Locations. Discharge water quality--actual and designed. Ability to handle shipping.
Non-sanitary wastes. Sources. Volumes. Important contaminants (toxics). Produced by project. Not produced by project.
Discharge/treatment procedures. Capacities. Piping systems. How discharged/treated. Discharge limitations--imposed, actual. Residuals--actual, designed.
Discharges reaching harbor/river waters. Behavior in water, sediments. Dispersion. Settling tendencies. Chemical reactions in water. Effects on biota, aquaculture.
Possible needed retention and treatment systems: Feasibility. Costs. Cost effectiveness. Possible resource recovery.
Non-sanitary spillage from non-ship related activities. Types of spills. Frequency. Volumes. How handled. Retention/ recovery systems. Emergency routines.
Non-sanitary discharges/releases from ship repair. Paints. Paint compounds. Other chemicals--hydraulic fluids, etc. Antifoulants. Ship refuse.
Heated process water discharges. Electricity generation. Industrial processes. LNG condensa- tion. Port/harbor hydrography. Tidal prisms. Effects of heated water on biota. Use in aquaculture. Definition of mixing zones. Potential for blocking fish passage.
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[ ] 1.7.4
[ 1 2-o
r 1 2.1
[ ] 2.1.1
[ ] 2.1.2
[ ] 2.1.3
[ ] 2.1.4
[ ] 2.1.5
1 1 2.2
[ ] 2.2.1
[ ] 2.2.2
[ ] 2.2.3
Brine from desalinization plants. Efficiency of mixing. Salinity of receiving waters. Port/harbor hydrography. Tidal prisms. Efficiency of diffusion. Effects on biota, aquaculture.
LAND-RELATED IMPACTS.
Excavation for fill (rock or aggregate).
Loss of upland vegetation. Cropland. Windbreaks. Degradation of Upland appearance. Soil cover. Prevention of erosion. Mudslide potential. Flooding potential.
Damage from shore sand/gravel excavation. Coastal dunes. Destabilization of shorezone. Acceleration of inland dune migration. Increased sandstorm frequency.
Dust (fugitive emissions). From drilling. Truck traffic and construction equipment. Wind velocity, direction. Dust control and suppression measures.
Blasting and Its Effects. Control of debris. Danger from inadequate blast zone coverage. Work area restrictions. Safety regulations. Damage to aquifers. Noise. Dust. Threats to livestock.
Requirements for land restoration. Pre-construction assessment of land appearance. Aesthetics. Restoration techniques. Landscaping. Constructive use of restored land cover. Need for selection criteria for filled lands to avoid nearshore storm surge inundation.
Wetland damage and filling. Discussion of needs. Purpose.
Ecological value of wetlands. Agricultural use. Waterfowl use. Use by domestic animals. Use by other fauna. Unique vegetation. Food source for aquatic or non-aquatic biota. Irrigation water source.
Flood plain functions. River flooding retention capacity. Tidal flooding capacity. Water retention intervals. Flooding related to irrigation source capacity.
WatershedIgroundwater source quality: Groundwater recharge function. Groundwater discharge function. Relation to used aquifer(s). Source of surface streams. Flow rates.
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[ ] 2.2.4
[ I 2.3
[ ] 2.3.1
[ ] 2.3.2
[ 3 2.4
[ ] 2.4.1
[ 1 2.5
[ ] 2.5.1
[ ] 2.5.2
1 1 2.6
[ ] 2.6.1
[ ] 2.6.2
Runoff (longterm) from developed areas (including ports and harbor facilities). Receiving function for natural surface runoff. Receiving area for developed area runoff--municipal, industrial. Existing contamination input. Contaminant buildup rates. Present background contaminant levels.
Loss of usable uplands to expanding waterfront/industrial areas.
Types of land areas likely lost to industrial or waterfront use. Farmlands. Residential areas. Market centers. Commercial areas.
Extent to which relocation compensates for lost land use. Extent of involuntary re-settlement. Residential relocation. Replacement farmlands. Other replacement/relocation needs. Requirements for associated needs-water, sewer, electricity, roads, fuel, etc.
Noise from ports and harborside industry.
Planning for possible strategic location of noise sources. Determination of existing background. Prediction of noise addition. Buffer zones. Designation of special high noise areas. Control of construction noise. Suppression, muffled equipment.
Effects of dust and other airborne emissions.
Dust and other non-combustion particulates. Sources-- industrial, construction. Raw material storage. Intensity. Periodicity. Wind rose indication of most likely affected areas. Smothering of shorezones and coral reefs. Screening by vegetation, windbreaks.
Smoke and other combustion products. Sources--ships, traffic, industry. Emission composition (toxics?). Control equipment in place, required. Regulatory requirements/limits. Wind rose data to indicate probable impact areas.
Traffic burden proiections.
Existing traffic load. Roadway network. Traffic load. Accident data. Types of traffic. Periodicity. Weight loading. Pavement damage. Axle load limits, etc.
Projected traffic increases. Needed roadway additions/improvements. Important routes. Traffic loads --commercial, construction. Destinations. Needs for traffic control.
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[ I 2.7 Handling and disposal of solid shore penerated wastes.
[ ] 2.7.1 Important sources. Ships. Waterfront industrial areas. Residential areas.
[ ] 2.7.2 Means of transport/transfer. Ship-to-shore. Onshore. Vehicle types. Compactors. Intermediate collecting sites.
[ ] 2.7.3 Disposal methods.
[ ] 2.7.3.1 Incineration. Proper siting. Possible recycling. Possible emissions (toxics, etc., --see Section 2.5.2). Disposal of residual ash. Energy generation.
[ ] 2.7.3.2 Landfills. Proper siting. tect shoreline
Aquiferlgroundwater protection. Need to pro- from erosion, etc. Site preparation. Surface
[ I 2.8
[ ] 2.8.1
[ ] 2.8.2
t I 2.9
[ ] 2.9.1
[ ] 2.9.2
[ ] 2.9.3
[ ] 2.10
water control--runoff. Proximity to water supplies--surface and subsurface, farmlands. Materials deposited, including incineration ash. Avoid placement in nearshore areas subject to erosion. Use of filter cloths and silt fences.
Runoff from raw material storage.
Nature of materials. Salt. Sulfur. Metal ores. Refined concentrates. Potential for toxic releases.
Exposure effects. Typical storage conditions. Locations. Storage time. Weather- ing effects--rain, wind, sun. Health menace to workforce. Need for containment of runoff. Protection of groundwater. Need for enclosure, cover. Grain spillage--measures to prevent/control.
Waterfront drainage.
Drainage components. Contaminants (toxics?). Volumes. Oils (hydraulic, etc.).
Drainage collection systems. Extent of existing systems. Pavement "watershed." Collection conduits. Means of disposal. Cleaning/skimming for oil separation.
Biological effects of disposal. Effects if directed to rivers, streams, wetlands. Effects if directed to harbor, bay. Effects on fisheries, aquaculture.
Industrial liquid wastes not discharged to harbor. Possible hazardous/toxic.
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[ ] 2.10.1
[ ] 2.11
c I 3.0
[ 1 3.1
[ ] 3.1.1
[ ] 3.1.2
[ ] 3.1.3
[ I 3.2
[ ] 3.2.1
[ 1 3.3
[ ] 3.3.1
[ ] 4.1.1
Storage and handling methods. Storage sites. Containment structures and materials. Proper placement and management. De-toxification options. Recycling possibilities.
Visual impacts--location. Aesthetics. Structure. Painting. Attempts to blend with surroundings.
AIR-RELATED IMPACTS.
Important backpround information.
Meteorological data. Prevailing winds. Seasonal weather patterns. Storm tracks, frequency and severity. Rainfall records. Wind rose data. Identify probable downwind impact areas.
Background data on prevalence of present airborne substances. Individual carrying/travel capacities. Chemical reactions while airborne. Chemical reactions with water.
Identify sensitive areas. Farmlands. Forests. Grazing lands. Residential areas. Water reservoirs.
Fugitive emissions (see also Section 2.5).
Sources and control measures. Dust--types, sources. Wetting and other control measures. Enclosed conveyor loading systems for ships loading dry cargo. Construction activities.
Gases, smoke, and fumes.
Sources, components, controls. Industrial contributions. Ships. Residential background. Vehicle emissions. Background from other areas. Control measures. Regulatory limits. Health-threatening toxics. Threats to agriculture and fisheries.
HAZARDOUS MATERIALS/CARGOES.
Categories--gases, liquids, solids. Examples. Hazardous ratings. Condition--required for industrial processes, waste products, finished products.
Key considerations. Identity of materials. Volumes/quantities usually on hand. How stored. Location of storage areas--segregation. Shipping and handling procedures. Bunding and other containment pre- cautions associated with bulk storage and tank farms. Disposal of any hazardous wastes generated.
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1 1 5.0 SOCIO-CULTURAL IMPACTS. Tribal, cultural, ethnic, historical, religious aspects likely impacted by changes, including consequences of modernization and industrialization. Landscape factors integrated with culture, traditions, etc. How affected. Possible measures easing transition. Preserving traditions with minimum loss and disturbance. Removal of graveyards, etc.
[ 1 6-O
[ I 7.0
REVIEW OF EXISTING AND PROPOSED REGULATIONS AFFECTING THE PROPOSED PORT OR HARBOR DEVELOPMENT AND ITS CONSTRUCTION. Environmental. Safety. Financial. Criminal. Export-import. Labor. Foreign consultant/labor use. Laws, regulations tied to socio-religious traditions, etc.
NEED FOR CONSTRUCTION OR FACILITY OPERATION ENVIRONMENTAL MONITORING. Basis--Most Sensitive Environmental Considerations. Program Planning. Management and Regulation Enforcement, Program termination.
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PART III - TECHNICAL SECTION
1.0 WATER-RELATED IMPACTS
1.1 Impacts Caused by Dredging
1.1.1 Dispersal and Settlement of Resuspended Sediments
Disruption of bottom sediments can cause a variety of environmen- tal impacts. Problems arise in particular where sediments have been con- taminated by chemicals, petroleum hydrocarbons and domestic wastes. Toxics or contaminants released from the disturbed soils can go into solution or suspension and contaminate or cause severe mortalities among important marine and estuarine fishery resources. Particles resuspended may be rede- posited on bottom life either smothering it or forcing it to move elsewhere (if sufficiently mobile). Organics in the suspended material can deplete available oxygen from the surrounding waters and temporarily create stressed conditions for many aquatic animals. If suspended sediments are sufficiently concentrated and persist through extended operations, light penetration into the water column may be reduced--causing damage to light- requiring photosynthetic algae, corals and other aquatic organisms.
Sediments become resuspended during initial excavation and during transfer to nearby land depositories or barges if clam-shell or dragline equipment is being used. Hydraulic dredging may introduce less suspended material at the dredging site, but the required settling ponds and ultimate release of partially clarified water at a point distant from the dredging may cause impacts at that location. Sediment dispersal in the water column can be reduced by surrounding the site with silt curtains (if currents are not too strong) and by not permitting barge or land site overflow. Rnow- ledge of the area's hydrography (tidal and river flows) prior to starting work is essential in identifying areas most likely to be affected by the work. Excavation of soft bottom by dredging also removes the habitat of those forms living in the bottom sediments. If there is appreciable sedi- mentation in the area, new bottom sediments will form and restore the habi- tat after the work is finished.
1.1.2 Effects of Blasting
Explosive charges used to break up rock formations destroy bottom habitats. Compression effects of the blasting often injure or temporarily disable marine life some distance from the blasting site. In addition, the more general but less damaging disturbance of a blasting program will be to force mobile aquatic forms from the area until the work is completed. This last effect is important, and plans (seasonal scheduling) therefore should ensure that blasting does not disrupt migratory pathways of important fisheries.
Careful attention should be paid to the proximity and condition of nearby shorezones, bulkheads, and other structures to ensure that use of explosives poses no threat to their integrity.
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1.1.3 Results of Altered Bathymetry
Deepening of channels, anchorages and berth construction can alter patterns of tidal and river flow. Should these patterns evidence high flows, eddies, etc., hydrographic studies and modelling may be advisable to find ways to avoid creating undesirable situations. These situations can range from unsafe vessel maneuvering to requirements for frequent dredging or to disturbance of valuable fisheries resources. Deepening of channels can also cause undesirable changes in the penetration of salt wedge conditions.
1.1.4 Effects of Changing Shoreline Configuration
Bathymetric changes brought about by dredging (deepening or widen- ing of waterways, etc.) can alter flow velocities and directions. This possibility should be examined carefully to assure that planned changes will not alter existing shore zone configurations through erosion, accre- tion or shoaling. Increased water depths can result in intensified wave activity on the shoreline with consequent increased littoral sediment transport resulting in accelerated erosion or accretion.
1.1.5 Loss of Bottom Habitat, Shellfisheries, Fisheries, Fishery Food Sources
Dredging excavation of soft bottom can remove important bottom- living aquatic life. However the bottom will readily be recolonized by replacement benthic organisms within a few seasons. As the original habitat will probably have changed due to the dredging operations (e.g., sediment type, topography, water depth, current pattern etc.), the new population might differ from the original one. It is advisable to determine whether possible current pattern changes will jeopardize or encourage resettlement of the original bottom life and associated fishery resources.
1.1.6 Altered Groundwater Flows
Subsurface groundwater flows near the land-sea interface can be altered by dredging or blasting as part of harbor/port improvement. Should there be extensive freshwater flow toward the estuary, the dredging could accelerate the flow and lower watertable levels in the adjacent upland. If freshwater flows are minimal or slow, dredging and blasting could increase saltwater intrusion into nearby water supply aquifers. If these impacts seem possible, it may be advisable to locate alternate freshwater sources.
1.2 Impacts of Dredged Material Disposal
The problems associated with the disposal of dredged materials have become major issues in many parts of both the industrialised and developing world. The topic is of such international concern and subject to continuous research that a separate Annex to this report covers the subject in depth. See pages 47 onwards.
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1.3. Construction of Piers, Breakwaters, other Waterside Structures (New or Extension/Replacement of Existing Structures)
1.3.1 Filling or Excavation that Covers/Removes Bottom Biota or Habitat
Excavation for or filling on the bottom to support a breakwater, pier or other waterside structure will cause loss of the displaced or covered bottom habitat and its associated animal and plant life.
1.3.2 New Habitats Formed by Structures (Especially Pilings and Breakwaters
supply Erection of piers and breakwaters usually provides an abundant
of new attachment surfaces, i.e., habitats for marine/estuarine organisms. Breakwaters or other structures possessing quarried rock or rip-rap surfaces also supply much shelter for mobile aquatic animals. Organisms occupying these habitats (both attached and sheltered) may be desirable or undesirable. It may be advisable to know what undesirable species are common to the area, note the characteristics making them undesirable, and determine their desired habitats. If the effects of the
a significant problem, alternate construction plans may be ir
presence pose preferable.
1.3.3 Filled Structures (Including Breakwaters)
Such structures constitute sizable masses of artificial shoreline often projected into a bay, harbor or estuary. If tidal flows are substan- tial, these obstructions may create major disturbances in existing tidal flows, increasing scour in some areas and accelerating sediment deposition in others. If there are indications that sediment deposition may be mark- edly increased, provisions for more frequent maintenance dredging or addi- tional structures may be required. If there is indication that sediment deposition may be a very serious problem, opting for a piling-supported structure permitting some measure of unobstructed flow may be preferable.
If filled structures are selected, care must be taken to determine the effects on maintenance routines for channels and other dredged areas. Revised navigation patterns could be required.
Somewhat different in structure and configuration but presenting similar environmental concerns are submerged pipelines running across shorezones (well platforms, Single Buoy Moorings (SBM) or storm/sewage outfalls). Disturbances of the shoreline have inherent risks of initiating serious erosion, particularly if the shoreline is subject to extensive wave action. Protection of the pipeline(s), once in place even though buried, may require a breakwater-like structure. Intertidal areas can be disturbed and/or lost as a result, and extension of the protective structures into the nearshore waters may change shorezone currents, introducing altered areas of scour and shoaling.
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1.3.4 Disturbances from Pile Driving, Other Construction Activities
Pile driving and other waterfront construction activities cause considerable noise and vibration-- easily transmitted to the adjacent waters. This disturbance may temporarily cause displacement of fisheries and other mobile marine animals. All other things being equal, these animals will usually return to the area once the disturbance ceases.
1.3.5 Dispersal of Suspended Sediments
Construction of piers, bulkheads, breakwaters, etc., even when not requiring dredging, can disturb bottom sediments, increasing turbidity adjacent to the work site. Should examination of bottom conditions and hydrographic patterns indicate this might be a matter of concern, preventa- tive measures to minimize impacts (Section 1.1) should be considered. Otherwise, bottom organisms may be smothered by sediment deposition, light penetration in the water column may be reduced, and fisheries can be tempo- rarily displaced during the construction period.
1.3.6 Piling-Supported Structures--Effects
Structures extending into harbor waters and supported by pilings driven into the bottom can impose several impacts on the site and vicinity. Piling Installation will disturb the bottom beneath the proposed structure, destroying some of the bottom habitat and temporarily displacing the mobile bottom animals and local fisheries (see Section 1.3.4). In addition, the structure, when completed with decking, will shade the area underneath and possibly diminish survival by attached algae and other aquatic plants. Presence of piling clusters will alter the habitat to some extent and may encourage the presence of either desirable or undesirable species. Pilings will also slow existing tidal or river flows, thus increasing sediment deposition at some locations beneath the structure. Depending on local conditions, this shoaling tendency may extend to nearby navigation zones, necessitating more frequent maintenance dredging. Other nearby areas may experience increased scouring. The nature and value of local aquatic resources should be examined and resulting hydrographic conditions eval- uated before beginning the project.
1.3.7 Release of Preservatives From Installed Timber Structures
Recent studies have indicated that the practice of impregnating wood materials for protection from marine borers and rot may, when water exchange rates are minimal, affect the local aquatic life. If water flow exchange rates appear slow or minimal at a site, it may be advisable to study this aspect. For example, pressure impregnated creosote piles and other components for marine structures are banned from use by some authori- ties.
1.4 Alteration of Harbor/Port Ship Traffic Patterns
1.4.1 Changes in Channel, Anchorage, and Turning Basin Locations
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If shallow conditions exist at the sites of these planned changes, improvement dredging may be required. The impacts of dredging (improvement and frequency of maintenance dredging) and disposal should be determined (see Section 1.1).
1.4.2 Relocation of Navigation Markers, Moorings
Care must be taken to assure that navigation aids such as beacons, markers, ranges, and buoys for channels and anchorages are precisely located and their visibility and marking appropriate with local and the International Association of Lighthouse Authorities Maritime Buoyage Systems. If the port vessel traffic is or will be considerable, Vessel Traffic Systems (VTS) will be required and possibly separate incoming and outgoing channels may be required - (lane separation schemes).
1.4.3 Addition of new Channels, Anchorages, Turning Basins Requiring Improvement Dredging
See Section 1-l for range of dredging and dredged material disposal impacts.
1.4.4 Improved Procedures for Vessel Traffic Control
If improved or expanded port and harbor facilities will lead to either or both increased ship traffic and use by larger vessels, improved vessel traffic control may be necessary to ensure safe passage and minimize the possibility of collision - resulting in spills--as well as fires, explosions, and loss of life.
It should be determined whether ships using the port area will be required to have special equipment for positioning and safe navigation, i.e., radar, LORAN-C/DECCA/GPS and ARPA collision avoidance/intercept systems. Special shore-based radar and/or radar reflectors may be desir- able. Updated pilot qualification or additional training may be necessary.
1.4.5 Increased Provision for Vessel Handling and Servicing
It must be determined whether increased ship traffic/port use will require additional tugs, lighters, and mooring and pilot boats. It should also be determined whether there is a need for ship repair facilities.
1.5 Ship Discharges -- Oily Ballast, Bilge Water: Seware
1.5.1 Promulgation of Regulations
Critical factors in controlling discharges of pollutants in a port or harbor are promulgation of realistic enforceable regulations. Such regulations should establish permissible limits for discharges and include adequate deterrent penalties. The enforcement of these regulations in a port or harbor will be the single most effective way of maintaining a clean and biologically productive environment.
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The most important instrument for preventing pollution from marine transportation is the Internat.ional Convention for the Prevention of Pollu- tion from Ships, 1973, as modified by the Protocol of 1978 relating thereto (MARPOL 73/78), which controls discharge of harmful substances into the sea from ships. MARPOL 73178 consists of five Annexes as follows:
Annex I
Annex II
Annex III
Annex IV
Annex V
Oil - Ships are prohibited to discharge oil or oily water, such as dirty ballast water and oily bilge water containing more than 15 ppm of oil, within 12 miles of land. Other conditions apply to discharges outside 12 mile limits.
Noxious Liquid Substances in Bulk - chemicals are evaluated for the environmental hazard they may cause if discharged into the sea (Categories A,B,C and D). Discharge into the sea of the most harmful chemicals (Category A) is prohibited and tank washings and other residues of less harmful substances (Categories B,C and D) may only be discharged under certain condi- tions, e.g., total quantity, distance from the shore, depth of water, prescribed depending on the hazards. There are substances, e.g., water, wine, acetone, ethyl alcohol, for which no restrictions apply.
Harmful substances in packaged form - this is princi- pally oriented towards prevention of pollution by regulating packaging, marking and labelling and stowage.
Sewage - It is prohibited to discharge ship-generated sewage unless it is treated with an approved sewage treatment plant or at a certain distance from land.
Garbage - Produced on board a ship, food waste, dunn- age, packaging, etc., must be kept on board and dis- charged either ashore or into the sea under certain conditions, such as the distance from land. Discharge of all plastics is prohibited.
These Annexes of MARPOL 73/78 are all in force.3 Under Annex I, ports are obliged to provide facilities to receive oily waste and oily water from the ships using the port. The Guidelines for the Provision of Adequate Facilities in Ports, Part I, Oily Wastes, published by the International Maritime Organization (IMO) in 1976 provides Guidelines for determining the volume of oily wastes generated on different types of ships and the capacity of reception facilities required to handle these volumes.
21 As of January 10, 1990, the status of ratification by countries of MARPOL 73/78 was reported by IMO to be: Annexes I and II - 57 countries (85.25%); Annex III - 38 countries (48.06%); Annex IV - 33 countries (39.75%); and Annex V - 41 countries (60.67%). Annex IV was the last to enter into force.
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Similarly under Annex II, the ports are required to provide facil- ities to receive tank washings of Category A and highly viscous or solidi- fying Category B and C noxious liquid substances that are imported in bulk at the port. The reception facility may also receive tank washings con- taining other products; however, this is a commercial exercise. Part II, Residues and Mixtures containing Noxious Liquid Substances (1986 edition), of the above-mentioned Guidelines discusses the need for reception facili- ties for noxious liquid substances.
Sewage and garbage, whether they are discharged from a ship or from land, are a major source of pollution in ports and their environs. Legislative and Administrative measures should be taken to prohibit discharge of sewage and garbage into the waters of the port. Prohibition of discharge of such waste from ships requires provision of suitable reception facilities for these wastes. Part III - Sewage and Part IV - Garbage (1978 edition) of the aforementioned Guidelines provides a basis for determining the adequacy of facilities required by individual ports for the reception of sewage and garbage from ships.
An important source of harbor pollution is the discharge of oily ballast and oily bilge water by vessels using the port. As previously mentioned, implementation of the MARPOL 73/78 requirements limits the oil content of such discharges to less than 15 parts per million (ppm) in the port or its environs. Ships will generate oily mixtures during their normal operations and the following four categories have been identified:
1. Oily ballast water from cargo tanks of oil tankers 2. Tank washings from oil tankers 3. Oily bilge wastes from machinery spaces of all ships 4. Oily residues from purification of fuel and lubricating oils,
used lubricating oils and liquid and solid sludges from the cargo tanks of oil tankers.
To determine the capacity and type of reception facility required in a port a number of parameters must be considered such as ship design and type of propulsion machinery and operating routes, including reception facilities in ports previously visited. A number of oil loading ports have provided reception facilities for oily ballast and tank washings from oil tankers where the oily mixtures are treated to separate the oil from the water. The treated water should contain less than 15 ppm of oil when dis- charged into the harbor waters; however many administrations now require that the oil content must be less than 5 ppm.
The collection and treatment of machinery space residue does not normally involve large quantities but the eventual disposal of these resi- dues presents a number of technical problems that are currently being studied under a joint IMOlINTERTANKO project. Oily sludges generated from cleaning of oil cargo tanks also present some problems in final disposal; however, the increased application of Crude Oil Washing by tanker operators should result in a significant reduction in quantities of oily sludge generated.
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Smaller vessels such as tugs, pilot boats and other port craft are not normally fitted with oily water separating or filtering systems and port authorities should make facilities available to periodically remove oily bilge water from these vessels.
A further consideration is vessels that anchor in the port approaches either awaiting orders or a berth. A floating reception facil- ity such as a towed or self propelled barge should be available to receive oily wastes and garbage.
1.5.2 Environmental Sensitivity to Discharges from Ships
Discharges and spills from ships or shore facilities can result in the introduction of contaminants into the harbor waters. These discharges can be harmful to marine or estuarine life and also render fish and shell- fish unfit for human consumption. Many ports have relatively poor water exchange with the result that pollutants tend to have long residence times in the port environment.
Untreated sewage discharges can pose serious threats to the local population of the transmission of diseases and can also result in degrada- tion of water quality in a port.
Discharge of garbage into the harbor waters will result in un- sightly conditions on the shoreline owing to accumulation of non-biodegrad- able materials such as plastics, glass and metal containers. Plastic bags and sheets can block cooling water intakes or foul propellers of vessels and small craft using the port.
1.5.3 Development of Shore Facilities for Receiving Ship Generated Sewage and Garbage
Every effort should be made to prevent discharges of untreated sewage from ships. Most vessels are equipped with sewage treatment plants or holding tanks as many administrations do not permit untreated sewage discharges in ports. Connections should be available to permit pumping of sanitary wastes into a special or municipal sewage treatment system. Smaller vessels used for harbor services should be equipped with recycling or chemical toilets or holding tanks that can be discharged to shore facil- ities.
A collection and disposal system for ship generated garbage should be established for ships alongside and at anchor. Closable skips can be provided at the berths and a towed or self propelled barge fitted with skips can be used to collect garbage from ships at anchor. Disposal of the garbage is subject to local customs and practice but for public health reasons many administrations will not permit garbage from foreign vessels to be taken outside the port and incinerators are used by the port to dis- pose of ship generated garbage.
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1.5.4 Effects of Antifouling Paints
By their nature antifouling paints are inimical to aquatic life. They either prevent estuarine and marine organisms from attaching to sub- merged surfaces or kill them should they succeed in becoming attached- -causing them to relinquish their grip and fall off. Severe damage to aquatic life has been caused by antifouling paints containing organic tin compounds - eg tributyl tin.
Careless application of antifoulants can introduce significant concentrations into nearby waters, and marine life can be seriously harmed. In some situations, removal of old antifoulants and reapplication can also introduce harmful substances to the water. In this latter instance, the greater harm will likely be to bottom-dwelling organisms directly beneath the operations area (a floating drydock, for example) where the mixture of abrasive and old paint may fall directly into the surrounding waters. Concern for effects of antifoulants must be an important focus when identi- fying possible locations for ship repair and maintenance, as well as small craft harbors. These facilities should not be located where there will be a threat to local fishery or shellfish resources. It is important to iden- tify the kinds of antifoulants to be employed at a ship repair/maintenance facility. Concern about the poison potential of the tin-based antifoulants has caused their use to be regulated or banned in many countries particu- larly where vessels are berthed or anchored in shallow water areas.
1.6 Spills: Detection and Clean-up of Spills
1.6.1 Types of Spills
Operational spillages from vessels in ports can be prevented by regulations supported by an effective enforcement program and provision of adequate reception facilities for ship generated wastes. Accidental spills can and do occur owing to marine casualties (collisions, groundings, fires, etc.), failure of equipment (pipelines, hoses, flanges, etc.) or improper operating procedures during cargo transfer or bunkering. Such spills can involve crude oils, refined products or residual fuels, noxious liquid substances and harmful substances in packaged form. The more volatile oils are generally less harmful to the environment because they rapidly evapo- rate but they can present the hazard of fire or explosion. The more viscous oils remain on the water surface where they will move under the influence of wind and current. Chemical spills can result in the introduc- tion of water soluble toxic substances into the marine environment, which can have a deleterious effect upon marine organisms. Some chemicals - even in low concentrations - can taint fish thus reducing its marketability. Those substances that sink can smother benthic species and eventual recovery is difficult.
1.6.2 Resources at Risk
Identification of areas within the port that are sensitive to spillages should be a priority. Wherever feasible, oil and chemical hand- ling facilities should be located as far away as possible from environmen-
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tally sensitive areas such as mangroves, corals, aquaculture projects and amenity beaches. In planning response operations these areas should be given first priority. Shore-based industrial installations using sea water for cooling or processing should also be clearly identified together with the location of their water intakes and discharges.
1.6.3 Spill Clean-Up Measures
A marine emergency contingency plan should be prepared for the port clearly outlining authority and responsibility for dealing with such incidents. Guidance can be found in the IMO Manual on Oil Pollution - Section II - Contingency Planning. Reporting and alerting mechanisms must be established to ensure that any spillage is promptly reported to the Port Authorities and those personnel involved are informed in order that they may take appropriate action.
Specialized oil spill response equipment should be available in the port to deal with small to medium spillages. This equipment may include containment booms, recovery devices, oil recovery or dispersant application vessels.
The equipment operators must be trained in deployment of the equipment, and the contingency plan regularly exercised to test reporting and alerting procedures. On a less frequent basis there should be deploy- ment of the specialized spill response equipment.
1.6.4 Dry Cargo Releases
Most such releases are likely to be wind-blown particulates from vessels loading or offloading or from waterfront stockpiles. If study indicates that particularly frequent dust-release events are likely and that harmful effects may result, there should be engineering/planning to determine the feasibility of requiring enclosed storage or loading/offload- ing facilities. Smoke effects may also involve particulates--as discussed in Section 2.5.2.
1.6.5. Hazardous Cargoes
This topic is treated separately in Section 4.0.
1.7 Waterfront Industry Discharpes--Sanitary and non-Sanitary
1.7.1 Sanitary Wastes
Treated and untreated sanitary wastes may be discharged to harbor/ estuary waters from waterfront industries. It is important to determine the daily volume of these wastes and the sources. If project-proposed activities will be the major source, project planning must include provi- sions for treating and handling the wastes. There must also be provisions for meeting required BOD (biological oxygen demand) and chemical limita- tions. If the releases are primarily not derived from project operations, the question of treatment and disposalshould nevertheless be addressed--in
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terms of the determined water quality stipulations of the harbor or estuary.
1.7.1.1 Sanitary Treatment Facilities
As part of project planning, existing or proposed waste water treatment facilities should be evaluated regarding capacity and efficiency. Any special contaminants should be identified (expected volumes, frequency of discharge, toxicities). There should also be a clear indication whether the contaminants will be attributable to project activities or not. Treatment/extraction procedures that are available or planned must also be described. Also specify water quality standards that must (should) be met. The impact of handling waste water from vessels must also be addressed.
1.7.1.2 Non-Sanitary Wastes
Non-sanitary wastes can consist of industrial discharges from a variety of manufacturing or refining processes released to the receiving waters of a bay or harbor. Prior to project planning it is necessary to know the nature, locations and volumes of existing discharges. Then deter- mine as accurately as possible their effect upon and combined impact with any aquatic effects attributable to the proposed project. It is imperative that any toxic or hazardous substances be identified and their impacts on receiving water quality and resident aquatic life be determined. Once these aspects are investigated, a similar assessment must be directed at the proposed project. Ultimately, measures should be taken, either in design engineering or in setting operational guidelines, to ensure that the project makes no appreciable additional contribution to the existing aquatic contaminant load.
1.7.2.1 Discharge/Treatment Procedures
Existing industrial operations constituting sources of contaminat- ing discharge should be examined carefully. If treatment processes are involved, their capacities and efficiencies should be evaluated and docu- mented. Many industrial discharges actually incorporate dissolved or sus- pended materials of value. Installation of recovery processes can retrieve metals and other substances, and, in the process, significantly reduce the potential for degrading the quality of the receiving waters. In assessing the effectiveness of in-place systems, aspects requiring critical examina- tion include the extent and effectiveness of settling ponds, the integrity of piping systems, proximity to residential areas or other industries, and --most important-- the nature and volume of any residuals reaching harbor waters. Testing may be advisable to determine whether existing discharge limitations are being met, and, no less important, the extent to which proposed project operations may alter the impact of existing discharges. To the extent these are judged substantial, mitigation measures (redirec- tion of discharges, component recycling, relocation of discharges, etc.) should be implemented with project plans.
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7.2.2 Discharges Reaching Harbor/River Waters
Industrial discharges frequently take place upstream of ports and harbors in fresh water. When these discharges meet saline water serious detrimental effects on both water quality and the residual plant and aquatic life can occur. Some chemicals and other substances, upon contact with even dilute salt water, undergo chemical change and tend to precipitate and settle on the bottom. Accumulations can create an abiotic zone where bottom-dwelling or attached plants and animals will be unable to survive. The same effect will also take place where discharges are made directly into salt water conditions. Such effects, though serious, will often be limited in area. Other substances will remain in solution or suspension and have broader influences. As an example, the discharges associated with the paper industry can be particularly damaging, increasing turbidity, and - perhaps most important - reducing dissolved oxygen levels below those required for the support of aquatic life. Under the project action to control the discharges based on the guidelines of the Montreal Convention on Land Based Sources of Pollution should be put into effect if possible. One of the difficulties which is difficult to combat occurs when the sources of the discharge is upstream but in another country.
1.7.2.3 Possible Needed Retention and Treatment Systems
If the proposed project involves industrial discharges to the bay, harbor or estuary, the full range of treatment and recycling processes should be evaluated. System feasibility based on local conditions is an important consideration, but, on balance, the most important focus should be on the environmental impact to the receiving waters.
1.7.2.4 Non-Sanitary Spillage from Non-Ship Activities
In addition to regular or periodic industrial discharges, atten- tion must also be directed toward the possibility that waterfront indus- trial activities will sometimes result in accidental spills into harbor waters. One of the most common of these will be the discharge of hydraulic oils due to mechanical leaks and hose failures. Although volume per acci- dent may be relatively small (typically about 60 gallons), the frequency of events, particularly in those areas where machinery maintenance is poor, may lead to this being a major cause of harbor water pollution. The extent to which it can occur as part of project construction and operation should be estimated and efforts made to reduce its frequency. In addition, emer- gency routines should be implemented as part of project plans to prevent such events from affecting harbor waters.
1.7.2.5 Non-Sanitary Discharges/Releases from Ship Repair
The impact of careless antifouling paint use has been discussed (Section 1.5.4). Other materials perhaps less toxic or hazardous but still harmful to the aquatic environment may be discharged into the water adja- cent to ship repair yards. Paints and general ship refuse are concerns as well. Drainage provision should include measures to prevent uncontrolled
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passage to the harbor or estuary waters. Also, operating regulations must be in place to discourage careless handling of materials.
1.7.3 Heated Process Water Discharges
A variety of waterfront industrial processes require large volumes of cooling water-- usually taken from the nearby bay or harbor and then returned with a heat load to the same bay or harbor. The receiving waters thus become an intermediate heat sink for the industrial activity generat- ing the waste heat. Prominent examples of operations having heated water discharges are electric generating plants, LNG condensation facilities, and high temperature ore refining operations. The release of large volumes of heated water, particularly into a semi-enclosed bay or harbor, can markedly change the aquatic biological character of the area if care is not taken to ensure adequate mixing and ultimate removal to the open ocean. Important information required to make decisions in this regard are location of valu- able fisheries and other estuarine resources, the volume of heated water discharged per unit time, the structural layout of the discharge--surface, subsurface multi-port diffuser, etc., bathymetry of the harbor/bay, and hydrographic conditions. The last, particularly important, must include estimates of the embayment tidal prism (volume of water exchanged per tidal cycle), current patterns, and ambient natural heat load of the receiving waters.
In colder climates heated water discharges may increase the pro- ductivity and diversity of estuarine and marine life. Aquaculture opera- tions can benefit from thermal discharges if no harmful substances are present in the discharge. In warmer places this growth advantage is usually lost, and water temperatures may rise to lethal levels for many organisms. Engineering considerations should include description of the expected mixing zone (zone adjacent to the discharge where heated water and harbor water mix at the moment of release --area of the highest tempera- ture). The discharge system should be designed and located to ensure that the mixing zone does not prevent passage of migratory fisheries.
1.7.4 Brine from Desalinization Plants
Arid lands frequently produce potable water supplies via desalini- zation plants located, of necessity, along seacoasts or harbor waterfronts. The extracted salts are often returned to the sea as highly concentrated brines. These are subsequently diluted in the receiving waters. Brines are generally heavier than the receiving waters and sink to the bottom largely unmixed and undiluted. If salt concentrations are very high, bottom life can be harmed--particularly if the area is not usually subject- ed to the full salinity of the open ocean.
Desalinization plant location and design will call for maximum separation of intake and discharge to prevent recirculation of the highly saline discharge. Care must be exercised to ensure that the discharge does not impact directly on any fisheries, shellfisheries, or aquaculture opera- tions. Also, if at all possible, the discharge should take advantage of
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prevailing currents and harbor tidal flows to maximize dilution and speed removal to the open ocean. The hydrographic considerations basic to hand- ling heated water discharges also pertain here: tidal exchange, tidal prism, mixing zone, etc.
2.0 LAND-RELATED IMPACTS
2.1 Excavation for Fill (Rock or Aggregate)
2.1.1 Loss of Upland Vegetation
Creation of quarries and borrow pits require removal of topsoil and other near-surface cover, making the land unavailable for agriculture, residence, recreation, grazing, etc., and exposing the soils and rock beneath to the action of sun, weather, wind, etc. Plans to establish sources of sand, gravel or rock must, of course, be directed at locations having the desired resource. Nevertheless, the value of lands marked for destruction must be considered, particularly when alternative sites for construction materials are available. Land functions lost include use as crop or grazing land, loss of existing or potential residential areas, loss of timber --if tree covered, or windbreak capabilities, and loss of erosion- prevention capabilities-- resulting in greater possibility of cave-ins, wind-driven dust, and mudslides. The loss of the rainfall retention cap- ability of the topsoil and its vegetation increases the rapidness and volume of runoff, thus producing greater potential for flooding at lower elevations in the watershed. Licences or permits for this type of activity must include provisions and funding to ensure that the lands are adequately restored to acceptable standards after the borrowing operations are terminated.
2.1.2 Damage from Shoreline Sand/Gravel Excavation
Should excavation for sand and gravel be planned in a shoreline zone possessing beaches and sand dunes, alternate sources should be sought if possible. Removal of sands and gravels from the shorezone or dune areas immediately adjacent to the shore can result in destabilization of the entire shorefront, leading to erosion and reshaping of the entire shoreline region, and, if the shore is subject to considerable wind forces, possible acceleration of dune migrations-- toward the shore and ultimate destruction or inland to bury desirable vegetated lands. Persistence of onshore winds can result in increased sandstorm severity with resulting degradation of impacted upland areas.
2.1.3 Dust (Fugitive Emissions)
Dust sources can include not only unvegetated areas open to weathering and wind but also drilling operations in quarries and truck traffic hauling from excavation sites. Construction equipment on site can also be a source of dust. In assessing the severity of any expected envi- ronmental impacts, special attention must be directed at prevailing wind directions and velocities and areas most likely to be affected--farmlands,
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residential areas, etc. If the impacts are judged significant, dust suppression and control measures should be incorporated into project plans.
2.1.4 Blasting and Its Effects
The use of explosive charges to break up rock (or abandoned con- crete structures) can incur severe effects leading to critical environmen- tal impacts. Most important, it is essential that blasting areas be cleared of workers and onlookers at the time demolition charges are set off. If there is risk to workmen or nearby populated areas, shock-absorb- ing "mattresses" should be placed over the areas involved.
When blasting is conducted in rock formations near aquifers from which water supplies are drawn, there should be precautions to prevent as much as possible the fracturing of rock in such a way that subsequent drainage might lower the water table in nearby wellfields. Special seismic testing and a series of test wells may be advisable before beginning the blasting. Surface effects of blasting may also include disturbance of livestock in nearby areas.
2.1.5 Requirements for Land Restoration
Any project incorporating substantial disturbance of land areas should include in its planning stages a survey of the areas earmarked for disruption to describe their environmental nature and value. From this knowledge there can be developed, reflecting the anticipated extent and type of disturbance and degradation, a plan for land restoration once the rock or sand and gravel have been removed. This does not mean that resto- ration must re-create the original environment. It is unlikely that that would be possible. Instead, planning should focus on using the ultimate topography and other characteristics of the excavations to the best advan- tage. Thus, restoration may involve changing the area into something quite different than its original state, but, nevertheless, much improved over its state if otherwise simply abandoned.
2.2 Wetland Damage and Filling
Marshes, swamps and other low watery areas, collectively called wetlands, often occur in abundance along shorelines. Their availability and their level elevation make them prime targets for filling to easily produce large spaces for expansion of industry, etc.
2.2.1 Ecological Value of Wetlands
Extensive research in many parts of the world over many decades has documented the unquestionable ecological value of wetlands. They serve as flood storage reservoirs and groundwater recharge areas. They have very high productivity rates providing food for a large variety of animal resi- dents and for many fisheries and invertebrates through their immense volumes of organic outflow. Waterfowl feed, nest, and find shelter in them. To remove wetlands is to increase the frequency and severity of
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floods, lower water tables and reduce the diversity and numerical abundance of plants and animals in the area.
Wetlands obviously vary in their nature and plant/animal composi- tion. Many are important food sources for man or his domestic animals- -although not cultivated in the usual sense. Irrigation systems may draw their water in whole or part from wetlands. Their destruction, then, is a matter of great concern and, in the long run, can only degrade the area involved.
2.2.2 Floodplain Functions
Wetlands serve as important flood storage areas, allowing immense volumes of water to be held and then released slowly to emptying streams. Estuarine or coastal wetlands serve a similar function by allowing storm- driven tidal inflows to overspread large areas without damage or harm to human habitation. Also, freshwater wetlands can serve as important reser- voirs for irrigation systems.
2.2.3 Watershed/Groundwater Source Quality
Also as noted, wetlands can be important groundwater recharge areas--if normally filled with freshwater. In some situations wetlands are actually groundwater discharge areas-- usually when definite surface inflows are not readily detectable. In the latter instance, the wetlands may be the source of important streams critical to the lives of downstream inhabi- tants. The "absorbing" nature of wetlands, when performing as a stream source, serves as a natural regulator of downstream flow rates, preventing flash floods and washouts.
2.2.4 Runoff (longterm) from Developed Areas (Including Ports and Harbor Facilities)
Because of their relatively low elevation, wetlands are usually receiving basins for surface runoff from surrounding uplands. If indus- trialized, residential or otherwise altered areas are located nearby, they, too, will contribute to the runoff accumulation in a wetland. The result can be a contaminant build-up inasmuch as wetlands tend to collect and hold substances introduced by entering waters. By the same token, waters leav- ing a wetland by outflowing streams will tend to be cleaner than those contaminant-bearing flows that entered. Wetlands, therefore, become "sinks" for contaminants, and over time may show a appreciable background build-up of various compounds, metallic ions and other substances. Should project plans call for increased runoff to a wetland, determination of background levels for any suspected contaminants will be advisable. Then background data should be examined and compared with the projected inflow of contaminants expected to be generated by the project to assess the prob- ability of any increases being harmful to the wetland and reducing its functional value.
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2.3 Loss of Usable Uplands to Expanding Waterfront/Industrial Areas
2.3.1 Types of Land Areas Likely Lost to Industrial or Waterfront Use
In addition to wetlands being filled to provide additional indus- trial or waterfront space, various other types of landforms and land uses (i.e., farmlands, croplands, grazing lands, residential areas, market centers, and commercial properties) can be eliminated by expanding water- front and industrial activities. Loss of each type can incur considerable environmental impact. The extent and magnitude of these impacts depends on the unique value of each area type and the extent to which other locations can supply suitable replacement by involuntary resettlement of inhabitants and their activities.
2.3.2 Extent to Which Relocation Compensates for Lost Land Use
The World Bank now has systematic and detailed policy designed to ensure successful resettlement. The two foundations of this policy first ensure that the displaced people shall be preferably better off and certainly no worse off after relocation. Second, the planning and financing of resettlement is an integral part of the project.
Preliminary planning must identify areas to be utilized in indus- trial and waterfront expansion or development and must indicate the extent to which these land-use conversions will force population resettlement. Although involuntary resettlement must be viewed as an environmental impact, it is important to realize that attempts to attach values to land- use losses and to the disruption associated with relocation may meet with little success because of emotional attachments to lands and surroundings. Every attempt at minimizing such moves and mitigating their impacts must be carried through with great sincerity and include extensive local government and community involvement. There must be a thorough examination of all associated community needs at any relocation site--water, sewer, electri- city, roads, fuels, social services and schools are typical examples of important concerns. Involuntary resettlement must include careful conside- ration of the need for employment opportunities. World Bank Technical Paper No.80 of May 1988 "Involuntary Resettlement in Development Projects" will provide guidance on how to approach these issues.
2.4 Noise from Port and Harborside Industry
2.4.1 Planning for Possible Strategic Location of Noise Sources
Initial study must identify existing noise sources, their charac- ter, and their daily cycles. Then predictions must be prepared detailing anticipated additional noise levels attributable to the project. If sub- stantial increases seem possible, plans to reduce noise impacts may lead to designating high-noise areas removed from other less noisy sites and from residential locations. Noise suppression measures may be advisable employ- ing muffled equipment, etc. There should also be a determination of the need for controlling and suppressing construction noise--for example, pile-
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driving (construction phase only) and use of compressors and drilling machinery.
2.5 Effects of Dust and Other Airborne Emissions
2.5.1 Dust and Other Non-Combustion Particulates
Dust sources and resulting impacts have been reviewed previously (Sections 1.6.4, 2.1.3). Sources include various industrial operations (ore crushing, for example), construction activities, outdoor storage of raw materials and other particulates (ranging from coal and limestone to grain and wheat storage, for example). Determination of possible environ- mental impacts must focus on source location, prevailing winds (direction and average/minimum speeds and duration) and areas most likely affected. Reduction or prevention of impacts can employ vegetation screening, use of vegetational or structural windbreaks and covering or enclosure. Wetting techniques and use of calcium chloride can reduce construction-caused dusts.
2.5.2 Smoke and Other Combustion Products
Although having properties and characteristics in common with dust and dust problems, smoke and other airborne combustion products can present more serious problems primarily because of the greater potential for dis- tributing toxic or hazardous substances and for the generally greater capa- city for dispersal. This topic is treated more fully in Section 3.3.
2.6 Traffic Burden Projections
2.6.1 Existing Traffic Loads
If port or harbor expansion or upgrading will result in more vehi- cular traffic, the increases and their impacts must be evaluated. Back- ground data required, if available, should include an up-to-date delinea- tion of the existing roadway network with indication of any expansion or improvement either underway or in the planning stage, quantification of present traffic loads and their periodicity, accident data with indication of severity (casualty losses, deaths and injuries), and any special charac- teristics of traffic (trucks, taxis, buses--frequency, routes, etc.).
2.6.2 Projected Traffic Increases
Once background data has been accumulated and analyzed, project increases can be integrated into the study. Important aspects will be the nature of the increases (workers commuting, trucks, tractor-trailers, heavy loads, Hazardous Cargoes (HC), etc. general commercial traffic), the nature and patterns of congestion, and routes likely to carry the expanded burden. With these projections developed, preliminary plans should be developed for improved roads and highways, new bypass routes to serve the additional traffic, and needs for traffic control. Additional problems include over- nighting of trucks and drivers, trucks waiting for port access, damage by
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trucks to roadways, and spillages from trucks. An important factor in developing these requirements is an examination of the secondary impacts- -traffic increases not directly attributable to the project but expansion of residential, market and commercial areas due to the enlarged industrial employment base.
2.7 fl[andling and Disposal of Solid Shore Generated Wastes
2.7.1 Important Sources
Solid wastes ranging from general rubbish and garbage to discarded industrial materials and construction rubble pose serious disposal problems for even smaller port and harbor communities. Important sources include residential and commercial areas; industrial plants; berths, cargo handling areas and warehouses: and, berthed and anchored vessels.
2.7.2 Means of Transport/Transfer
Accurate figures for existing solid waste volumes should be obtained. Then projections can be developed for anticipated increases (major categories may be useful, as well). It must be determined what means, if any, are presently used for transporting solid wastes to the disposal site. Integration of present volumes and waste categories with projected increases will indicate whether transport system capacity must be expanded or upgraded. Important aspects include means of transferring solid waste from ship to shore-based receiving sites (bins or simply loading/unloading areas), vehicles used to collect and haul to disposal sites, use of compactors, and regional collecting facilities.
2.7.3 Disposal Methods
Solid wastes may undergo sorting for extraction of recyclable materials or may be incinerated or deposited in a landfill area.
2.7.4 Incineration
Burning of combustionable solid wastes is most effective if prior sorting removes materials suitable for recycling. Such a process may also remove some of the materials that are not burnable. There is well-develop- ed technology for incineration of solid wastes with process refinement continuing. From the viewpoint of environmental impact, several key issues should be addressed: siting-- a location distant from residential and agri- cultural areas, where there is sufficient space for stockpiling solid wastes if the load exceeds plant capacity (or the plant breaks down): the nature of combustion emissions (toxics, gases, smoke, scrubbers--available or not?); facilities for handling and temporarily storing fly ash and bottom ash. Electricity generation as a byproduct may be possible if energy needs and waste volumes are sufficient.
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2.7.3.2 Landfills
The term "landfill" is in some instances simply a euphemism for "dump", or well-removed location, of no apparent human use, where every- thing no longer desired is simply deposited. This is not the concept of a landfill. A landfill is a carefully selected site where solid wastes are deposited in a carefully controlled manner and then covered with acceptably clean soils. Ultimately, all or a specified portion or cell of a landfill is declared full, and permanent soil cover is laid over it and vegetation planted on it.
From the environmental viewpoint, key considerations center on determining that water passing down through the landfill and leaching out contaminants does not enter important aquifers used by neighboring communi- ties. In addition, daily and final cover prevent winds from removing recently deposited lighter materials and also make the site less accessible to birds and rodents. Rainfall/surface runoff is also a concern, and design parameters and topographic features should be employed to control and direct the flows so that serious impacts are avoided. In general, solid wastes for landfill are not sorted for recycling. All categories of general refuse are accepted. Incineration ash from solid waste burning (if both alternatives for disposal are employed) and other furnace operations are also deposited thereon (and sometimes used as daily cover).
2.8 Runoff from Raw Material Storage
Many raw materials, particularly from mining operations, are, because of their large volumes, stored in exposed situations while awaiting processing or loading onto ships.
2.8.1 Nature of Materials
Typical examples of bulk materials frequently stored outdoors include timber--cut or uncut, salt, coal, sulfur, feldspar, unrefined ores, and refined ore concentrates. Depending on their nature and on prevailing local weather conditions these storage areas can be sources of contaminants or toxic releases.
2.8.2 Exposure Effects
Factors in determining the environmental impacts attributable to exposure and weathering are varied but include length of exposure, nature of material, weather conditions, rainfall, wind persistence and direction, sun exposure, and handling procedures. The identification of impacts must incorporate plans for controlling all runoff from the stored materials and the surrounding area (dikes, drains, and perhaps retention/evaporation/ neutralization ponds), provisions for protecting workers handling the mate- rial, measures to prevent leaching into the groundwater (impervious base required?) and controlling drainage to adjacent harbor waters. If serious concerns regarding weather effects persist, methods for covering the material may be required.
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2.9 Waterfront Drainage
All too often, runoff from waterfront areas is allowed to flow unimpeded into the harbor or estuary. Left unchecked, serious contamina- tion and water quality degradation can result.
2.9.1 Drainage Components
The possible range of contaminants reaching harbor waters is very broad--the potential for raw material storage drainage in Section 2.8.2 provides some insight. However, the principal constituents are oils, diesel fuels, gasoline and hydraulic oils-- the last being the most common and perhaps the single largest contributor in volumes.
2.9.2 Drainage Collection Systems
To the extent possible, direct drainage from wharves and piers and adjacent surfaces to harbor waters should be prevented. Areas should be paved and sloped to direct flows to catch basins--not over the edge of piers. Catch basin systems should be blind (requiring periodic pumping out) or be connected to collection systems directing flows to a central location where separation of oils and water can be accomplished. The cleaned waters then can be released to the harbor upon meeting standard discharge limits for residual release concentrations (see Section 1.7).
2.9.3 Biological Effects of Disposal
Discharge of untreated, uncleaned waterfront drainage to harbor waters can have serious effects on aquatic life. If directed to nearby wetlands, these materials can easily transform natural, viable areas into lifeless wastelands having little value in the natural environment or to neighboring residents. If directed to streams and rivers above tidal influence and in sufficient quantities, biological life in the waterways may essentially be eliminated. Should a stream or river be a source for municipal water supplies below the release point, the water might become unusable, and the source would have to be abandoned. Bay, harbors and tidal portions of rivers (estuaries) have a greater dilution potential, and waterfront discharges may not appear to be as serious. Nevertheless, per- sistent chronic discharges will reduce fishery, shellfishery and aquatic plant life diversity and seriously reduce water quality. Aquaculture ope- rations would probably no longer be possible. The ease with which water- front drainage discharges can be prevented make this one of the most readi- ly available steps to be taken in a harbor/river/estuary clean-up program.
2.10 Industrial Liquid Wastes not Discharged to Harbor
Liquid industrial wastes--for example, wash solutions from elec- troplating operations-- must not be released to harbor, river, or ocean waters, but rather collected and treated to remove or neutralize toxic or hazardous chemicals therein.
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2.10.1 Storage and Handling Methods
Environmental planning for ports and harbors must carefully address the matter of liquid industrial wastes if it is determined that they will be present. Volumes and flow rates must be predicted, sources and processes identified and engineering plans developed for their control, storage and ultimate disposal. Properly designed transfer systems and storage facilities must incorporate high grade materials to ensure the integrity of all containment structures. Emergency control apparatus must be incorporated into all units, and workmen must be thoroughly trained in the use of the systems. Plant operations must include, along with engi- neering and construction, appropriate techniques for de-toxifying or neu- tralizing the solutions, and recycling operations where feasible. Finally, there must be assurance that ultimate disposal products carry minimum risk of harming the natural environment or threatening the public health.
2.11 Visual Impacts
To the maximum extent possible and in conformance with local cond- itions and public concerns, measures should be taken during the project design stage to minimize degrading visual impacts. Use of vegetation, imaginative painting to either please the eye or to blend with neutral, agreeable backgrounds, and strategic positioning of buildings and struc- tures will significantly lessen disagreeable visual impacts.
3.0 AIR-RELATED IMPACTS
3.1 Important Background Information
3.1.1 Meteorological Data
Consideration of factors causing air-related environmental impacts must proceed from a base of meteorological data describing short-term and longterm weather patters at the project site. Availability and comprehen- siveness of these kinds of information will vary from location to location. Proximity to an airport with a fairly long operating history will usually ensure availability of some such data. However, if the airport is somewhat distant from the coast, careful adjustments may be necessary to obtain a clear picture of recurring conditions at the project site. Data most needed include prevailing winds (annual wind roses are very valuable), seasonal weather patterns, frequent storm tracks, storm frequency and seve- rity, and rainfall records. In addition, typical barometric, temperature and relative humidity data are useful.
The other key factors in determining the extent of the project's air-related impacts are the project site and delineation and characteriza- tion of principal downwind impact areas.
3.1.2 Background Data on Prevalence of Present Airborne Substances
If the project area and vicinity have several airborne pollutant sources, the background levels caused by their operation must be deter-
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mined. The components of these releases should be identified and their dispersion characteristics noted (how far do they travel and under what conditions?). The potential for photochemical reactions and reactions with moisture in the air should be estimated--from research results, not from site conditions.
3.1.3 Identify Sensitive Areas
Using the historical meteorological data, likely downwind sensi- tive areas must be identified and delineated--farmlands, forests, wetlands, water reservoirs, residential areas and grazing lands. Should an extensive meteorological history not be available, as much information as possible should be obtained from competent local knowledge. Ship pilots and fisher- men are possible sources. A simple temporary meterological station adja- cent to the site should be set up and as long a period of recording as possible obtained.
3.2 Fugitive Emissions (See also Section 2.5)
3.2.1 Sources and Control Measures
Finely divided particulates suspended in air and windblown from source to point of deposition constitute impact-causing dusts. Major sour- ces can be construction activities (earthmoving and rock drilling), traffic on unpaved roadways, fugitive emissions from outdoor storage of raw mate- rials, ores, and particulate refined products. Knowledge of prevailing winds and identification of areas most likely to be subjected to dust dis- persion set the basis for determining the seriousness of airborne dust impacts. Wetting, use of sprayed coagulants, sheet material, enclosure of storage areas and enclosed conveyor systems will appreciably diminish related environmental impacts.
3.3 Gases, Smoke and Fumes
3.3.1 Sources, Components, Controls
Background sources vary from electric generating stations, incine- rators (see Section 2.7.3.1), smelters, steel mills, and many other indus- trial operations ranging from ships at dockside and under way to vehicle emissions to residential heating and cooking. Components vary widely as well, depending on the source process. Background emission levels and composition should be determined before designing additional facilities that will add to the air pollution load. Control systems (scrubbers, etc.) may or may not be required by local authorities, but every effort--barring prohibitive cost-- should be implemented to avoid adding to the existing air pollution load.
Fumes can constitute a separate aspect in that they may not neces- sarily be associated with combustion or heat processes but may come as well from other types of industrial chemical processes. A common example is the air--petroleum vapors emitted from uncovered storage tanks or covered tanks
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when vented for refilling. Because of their nature and origin, they may also have a greater potential for harm-- to the environment and to public health. Control processes should be implemented (covering of tanks and trapping of vented emissions), utilizing recycling techniques or chemical absorption (reliquefaction), neutralization and burn-off stacks.
4.0 HAZARDOUS MATlJRIALS/CARGOES
4.1 Categories--Gases, Liquids, Solids
A hazardous material, in a general sense, can be any substance which has some inherent instability that under the right conditions can lead to fire, explosion or extremely damaging conditions perhaps caused by highly corrosive characteristics-- or a substance sufficiently toxic to be an immediate threat to life and public health if not properly confined and controlled. So defined, "hazardous material" covers a broad range of mate- rials, i.e., gasoline, liquefied natural gas (LNG), sulfuric acid, other corrosive chemicals, pesticides, and explosives--as examples. Some hazar- dous materials may be waste products; others, finished products; and others, unrefined natural materials (crude oil, for example). The single basic feature is that admitted into an uncontrolled situation, serious damage and extensive threats to life and health may result. See World Bank publications (1985a, 1985b) for comprehensive guidelines and procedures for conducting hazardous substance assessments.
4.1.1 Key Considerations
If hazardous materials or cargoes are or will be handled at the proposed port or port facility, precise information must be obtained regarding kind, amount and condition of the materials, how the materials will be handled and stored, and where the handling and storing will take place, and how any hazardous wastes generated will be disposed of. Unequi- vocal regulations must be established covering every aspect of their pre- sence at the facility--from arrival to manufacturing to processing to storage to dispatch. Special regulations may be advisable controlling or prohibiting other ship traffic in the port when a ship laden with hazardous material is arriving or departing. Where bulk materials are stored or liquids held in tank farms appropriate bunds and containment arrangements will be required to cope with possible failure or rupture of the storage system. The regulations, of course, are only as effective as the workers are trained, supervised, and made aware of the risks involved.
5.0 SOCIO-CULTURAL IMPACTS
The very best engineering, highly laudable environmental planning, and extensive economic justification can all serve to no avail if work practices, site selection or similar factors run counter to socio-cultural standards and traditions. Project planning must incorporate a comprehen- sive survey and result in a thorough understanding of local tribal, cult- ural, ethnic, historical, religious traditions. Failure to do so may essentially cancel any benefits from the project.
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There must be a careful examination of how port/harbor development or expansion will interact with the inhabitants of the area and the general surrounding population presumed to be benefiting from the project. Mea- sures should be designed to integrate the project into the landscape (in the broadest sense of the term) and to ease transition to a contemporary, more industrialized society-- while preserving valued traditions and culture.
6.0 REVIEW OF EXISTING AND PROPOSED REGULATIONS AFFECTING THE PROJECT AND ITS CONSTRUCTION
Project planning must also include a thorough review of local judicial structure as it may affect, or in turn, be affected by the project and newly imposed required regulations. The aspects to be carefully inves- tigated should include regulations influencing environmental values, safe- ty, harzardous substances, financial considerations, criminal behavior and punishment, export-import regulations, foreign consultant and labor-use, and laws or restrictions tied to socio-religious traditions.
7.0 NEED FOR CONSTRUCTION OR FACILITY OPERATION ENVIRONMENTAL MONITORING
All too often, once environmental compensation and/or mitigation measures have been satisfactorily defined and the project approved, con- struction and then facility operation follow with little heed paid to sub- sequent environmental concerns. In some cases, this lack of follow-up threatens to undo all the environmental protection plans carefully developed during the planning stages.
If, during the planning stages, specific environmental aspects appear to require the protection provided by construction and/or operation monitoring, it may be advisable to incorporate provisions into project documents as covenants requiring continued monitoring. Such provisions should spell out types of monitoring required, frequency of observation, reporting procedures, and necessary actions to be taken if the environment protective measures are violated. There should also be guidelines for reduction or termination of monitoring if anticipated impact threats do not materialize and longterm indications are that they will not occur in the future.
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PART IV - BIBLIOGRAPHY
International Maritime Organization (IMO) 1973. International Convention for the Prevention of Pollution from Ships with its 1978 Protocol (MARPOL 73/78) as amended.
International Chamber of Shipping (ICS) 1974. Tanker Safety Guide (Chemicals).
International Chamber of Shipping (ICS) 1978. Tanker Safety Guide (Liquefied Gas).
International Maritime Organization (IMO) 1978. Guidelines on the Provision of Adequate Reception Facilities in Ports - Part I (Oil); Part II (Noxious Liquids and Substances in Bulk); Part III (Sewage); Part IV (Garbage).
Pequegnat, Willis E. 1980. Analysis of the Impacts of Dredged Material Disposal in the Deep Ocean; Second International Ocean Dumping Symposium, Wood Hole, Oceanographic Institution. April.
Pequegnat, Willis E. 1981. Oceanographic Surveys required for Dumpsite Selection, Official Designation and Monitoring of Dredged Material Dumpsites in the USA; 3rd International Symposium on Dredging Technology, Bordeaux, France. March.
Kamlet, K.S. 1983. Dredged Material Ocean Dumping: Perspectives on Legal and Environmental Impacts; in: Wastes in the Ocean, Volume 2, John Wiley and Sons, New York.
International Chamber of Shipping/Oil Companies International Marine Forum/International Association of Ports and Harbours (ICS/OCIMF/LAPH) 1984. International Safety Guide for Oil Tankers and Terminals (ISGOTT)
The World Bank 1984. Environmental Guidelines (Office of Environmental Affairs) 461 pp.
The World Bank 1985a. Environment, Health and Safety Guidelines for Use of Hazardous Materials in Small and Medium Scale Industries (Office of Environmental and Scientific Affairs) Washington, D.C. 43 pp.
The World Bank 1985b. Manual of Industrial Hazard Assessment Techniques (Office of Environmental and Scientific Affairs) Washington, D.C. 99 pp & appendices.
International Maritime Organization (IMO) 1986. Control of Ships and Discharges.
The World Bank 1986. Overview of Port-Related Industries (Prep. by E.G. Frankel, G. Panagakos, G. Mahnken). Transportation Dept. 379 pp.
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Olson, Per H. 1987. Reception Facilities in Ports for Residues and Mixtures Containing Noxious Liquid Substances. Ports and Harbors (June 1987). pp. 19-28.
Olson, Per H. 1987. Environmental Protection, Port and Shipping Safety with Emphasis on Noxious Liquid Substances. Port Management and Operations, Port of Gothenburg Consultancy AB (June 1987). 24 PP.
The World Bank 1987. An Analysis of Port Engineering Standards (prep. by J.E. Clifford and J. Lethbridge). Transportation Dept. 128 pp.
International Maritime Organization (IMO). Manual on Oil Pollution. Section I - Prevention (1983 revised edition); Section II - Contingency Planning (1988 revised edition); Section IV - Practical Information on Means of dealing with Oil Spillages (currently under revision).
An&1 The Environmentally Sound Disposal of Dredged Materials
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TABLE OF CONTENTS
1 Introduction 51
The purpose of this document. ............ 52 What are dredged materials? ............. 52 The reason for environmental controls on dredged materials disposal ................. 53
2 Scone of the Problem 55
What is pollution? ................. 55 How do sediments become contaminated? ........ 56 Contaminated sediments and environmental effects . . 56 Environmental standards ............... 57 Pre-project characterization ............ 57
3 International Agreements Renulatinz Pollution 60
The conventions ................... 60 _ Land-based sources of contaminants and contaminated
sediments ...................... 62 Application to dredged materials .......... 62
4 Effect of Environmental Restrictions on the Dredging and ‘hanSDOrtatiOn of Materials 63
Types of restrictions ................ 63 Port design ..................... 63 Dredging equipment ................. 68 Selection of equipment. ............... 68
5 Review of disDosa1 ontions 71
Option types .................... 71 Discussion of disposal options ........... 71 Minimizing costs through careful planning ...... 76
6 Recommendations and Conclusions 77
Recommendations ................... 77 Conclusions ..................... 79
7 Bibliozranhv . . . . . . . . . . . . . . . . . . . . . . . 81
Attachment 1 - London Dumping Convention - Annexes I, II, III Attachment 2 - Guidelines to the Disposal of Dredged Materials
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1. INTRODUCTION
/
As part of its policy to ensure that environmental considerations form an integral component of all lending operations, the World Bank prepared and published INU-5 "Environmental Considerations for Port and Harbour Development" in January 1989. Although that report discusses the disposal of dredged sediments, increasing regulatory constraints and environmental concerns with marine disposal in general led the Bank to augment the discussions with this report which specifically addresses the various disposal options available today and future directions.
Increasing public concern for the quality of the marine environment has led the heavily-industrialised European and North American countries and Japan to implement regulations controlling dredging and the open-water disposal of dredged sediments. Without careful consideration of the impacts of these regulations, many ports could be subject to severe limitations as to their maintaining navigational access. Sediments from most maintenance dredging projects are recently deposited materials often contaminated due to pollution from a variety of point (oufalls) and non-point sources (general run- off). These sources contribute chemical substances now considered as environmental or health hazards. For example, 17-331 of the projected 60 million cubic metres to be dredged in the Netherlands in 1990 are considered so badly polluted as to require disposal within confined disposal facilities.
The following table1 illustrates the typical annual volume of maintenance dredging activity.
u Source: J.G. Villot, Terra et Aqua 30 November 1985.
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The Puroose of this document
The World Bank is associated with many dredging projects through its lending operations to countries for infrastructure development or improvement. The purpose of this report is to provide a more in-depth discussion of the disposal of sediments dredged during construction or maintenance projects and it specifically reviews:
* the scope of the problem;
* inter-governmental agreements regulating pollution;
* disposal options;
* future options; and,
31 the costs associated with poor environmental planning in the design of dredging and port development projects.
The document is purposely brief so as to provide an overview of the topic. It is intended for both World Bank staff and project staff from the Bank's borrowing countries. It is not intended to be a definitive work on dredged material disposal. It must also be appreciated that there is continuing research and development being undertaken in many countries to provide an economical answer to the problem of dredging harbour sediments, while at the same time minimizing the environmental impact of the disposal of such sediments.
What are Dredged Materials?
The term dredged materials encompasses sediments, soils and rocks excavated underwater for the purposes of providing or maintaining channels, ports, and waterways or generated during the construction of port or waterway facilities (e.g., berthing facilities, turning basins) in support of maritime-borne commerce, fishing fleets and naval defence.
Dredged materials can be broadly divided into four categories:
1) Material derived from maintenance dredning of areas affected bv sedimentation resulting from rivers or estuaries or land run-off. This material tends to be fine-grained (silts and clays) and often contains large quantities of organic matter (plant detritus to sewage).
The process of sedimentation and the nature of the materials typically creates a heterogeneous distribution of contaminants within the sediments, including particular "hotspots". The variation in the vertical profile of contaminant concentrations is a function not only of the depositional history, but also the frequency of dredging, the environmental quality of the overlying waters, effluents and run-off, and the history of activities in the port area. This category of materials is usually the most
2)
3)
4)
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contaminated of the four groupings and therefore is the focus of the environmental concerns as to the regulation of the disposal.
Material derived from maintenance dredging of sand bars at the entrances to harbours or channels. This material tends to be fine to coarse-grained sands resulting from long-shore transport of materials or from erosion/accretion processes near the harbour entrance. The nature of the sources of such materials tends to result in much less-contaminated materials compared to Category 1. This material can often be used beneficially such as for beach nourishment or construction fill material.
Material derived from capital dredging within a oort (e.g., a new berthing facility). As described in Category 1, sediments within this area represent a layering of sediments over a period of time and therefore the concentrations of contaminants can vary substantially over a vertical profile of the dredge cut. Typically, the upper layer is the most contaminated, is organic-rich and fine-grained. The deeper materials are usually less contaminated and often coarse-grained or hard-pan materials, however, historical contamination (eg. shipyards, spills, etc.) can reveal contamination even in these materials.
The variable nature of the sediments leads to a multi-option program for disposal with some materials having to be contained, while other materials being suitable for open-water disposal or a beneficial use.
Material derived from capital dredging of channels or outer harbour areas. This material tends to be relatively coarse-grained and uncontaminated, although the nature of the materials is a function of the historical activities within the region. Such materials are often used to counter shoreline erosion, for beach nourishment or as fill materials.
The reason for environmental controls on dredged materials disDosa1
Traditionally, dredged materials have been disposed at an open-water site without limitation. The increasing concern with regard to the environmental impact of disposal in the marine environment, in particular of materials that could be described as "contaminated or polluted" has led to the imposition of restrictions on such disposal, including placement within containment facilities or not permitting dredging. Such regulation through either restriction of activities or increased costs can limit the dredging and thereby have a marked effect on the economy of a region or even a country. Such effects have to be balanced against the benefits to the environment that will result.
Areas of sediment deposition typically contain fine-grained sediments and often contain high concentrations of organic materials. Such sediments are also well known as "sinks" for many chemical compounds, in particular those compounds known to be of environmental
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concern or health hazards as a result of several physical and chemical processes: 1) many organic contaminants (e.g., PCB, and pesticides) have a low solubility in water, are therefore primarily associated with suspended solids and are transported to the sediments via particle deposition; 2) when freshwater interacts with seawater there is a significant decrease in the solubility of many metals thereby promoting their precipitation; and 3) when freshwater interacts with seawater, the flocculation of suspended solids is promoted, increasing their deposition rate and that of the associated contaminants.
Since these zones of sediment deposition are also often the areas requiring routine maintenance dredging, such dredged materials typically contain contaminants considered hazardous or potentially hazardous. The identification of what chemical substances are considered hazardous or potentially hazardous has been established by various international conventions. Recommended concentrations of concern for these substances have often been implemented as regulated levels by the signatories of the international conventions, although there are differences in the absolute limits comparing national standards. Worldwide concern for the effect of wcontaminants" on the environment in general, and foodstuffs in particular, has led many governments to require special constraints on the disposal of such contaminated dredged materials. Constraints have been designed or imposed to limit adverse effects on the marine bio-environment; to limit specific effects on a fishery or shell-fishery; or to limit bioaccumulation of various contaminants leading to human health effects through consumption of contaminated biological resources.
In terms of the overall quantity of material to be dredged in the world, however, contaminated materials make up only a relatively small fraction. Thus, it is very important in the planning of any project to carefully characterize and describe the nature of the materials to be dredged - not just in an overall sense but location by location and at various depths. This permits the differentiation between those sediments which are truly contaminated and which require special handling and those which are little different from natural sediments in the region and could therefore be disposed at an open-water site. Although such characterization will require more than normal effort in preparation and pre-project assessment, significant financial savings can be obtained by not having to contain or handle in a special fashion all of the dredged materials.
The source of much of this contamination is land-based activities, such as industrial effluents, residential sewage and disposal and agricultural practices (land clearing, pesticide applications). The problems are not restricted to developed countries but occur worldwide. It becomes very important in port development to take into consideration how activities throughout the surrounding area can affect port operations through the unrestricted or poorly regulated entry of contaminants into the dredged sediments.
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2. SCOPE OF THE PROBLEM
What is Pollution?
Pollution' occurs when the concentrations of various chemical or biological constituents exceed a level at which a negative impact on amenities, the ecosystem, resources and human health can occur. Pollution results primarily from human activities. The sources of pollution are numerous, including such obvious examples as sewage, urban run-off, industrial processing wastes and effluents, coastal developments, shipping activities and atmospheric dust and fall-out. The chemical or biological constituents creating pollution are known as contaminants. More specifically they can be divided into inorganic contaminants such as zinc or lead; organic contaminants, such as pesticides, PCB or petroleum hydrocarbons; and biological contaminants, such as coliform bacteria and pathogens.
Physical impacts associated with dredged material disposal can also seriously damage habitat and interfere with other activities such as fishing. However, proper dumpsite selection can minimize these impacts.
The list of potential contaminants is very long. Our understanding of the hazards of such contaminants as trace metals, bacteria, or petroleum hydrocarbons is reasonably well based. However, within the past forty years, society has increasingly become dependent on plastics and various man-made organic chemical compounds (e.g., pesticides, PCB). Only now are we beginning to realize that the very properties that make such compounds so useful in everyday life, also make them very persistent in the natural environment.
Pollution is not a recent phenomenon resulting in a change in a country's economic status from an underdeveloped nation, but has occurred since the first concentration of Man around a port area. Recent industrialization has only accelerated the rate of contamination and increased the environmental problems related to dredging and dredged material disposal. Even in non-industrialized areas, where the requirement for maintenance dredging arises from river-borne siltation or other land run-off, such silts can contain fertilizers and pesticides from agricultural areas. Such contamination is the result not of industrial activities, but land-use practices within the adjacent watershed.
2J The Law of the Sea definition is "Pollution of the marine environment means the introduction by man, directly or indirectly, of substances or energy into the marine environment, including estuaries, which results or is likely to result in such deleterious effects as harm to living resources and marine life, hazards to human health, hindrance to marine activities, including fishing and other legitimate uses of the sea, impairment of quality for use of seawater and reduction of amenities."
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How Do Sediments Become Contaminated?
Many organic contaminants (e.g., PCB, and pesticides) have a low solubility in water, are therefore primarily associated with suspended solids and are transported to the sediments via particle deposition. Metal pollutants often enter the coastal waters associated with suspended solids in sewage or as dissolved metals from land-use practices and industrial activities. In reactions with seawater at pH 8 and a salinity of 25-30 ppt, the metals form new compounds which also tend to be deposited in the sediments. The end result is that most contaminants are finally deposited in the sediments.
Sediments requiring maintenance dredging are typically fine-grained and rich in organic matter. The sediments are fine- grained because the port is often designed or located in areas of low water circulation thereby promoting the settling of the finer grained sediments and associated organic detritus. The organic matter can be the result of input from sewers, industrial outfalls and general detritus. The decomposition of the organic matter consumes oxygen leading to anoxic, sulphide-rich sediments. These sediments create a physical-chemical regime which promotes the immobilization of associated contaminants.
Contaminated Sediments and Environmental Effects
The introduction of contaminants via sewage, run-off and effluents affects marine plants and animals in different ways. Fish kills due to the introduction of a very toxic substance are an obvious result. But, it is the long term low-level entry of contaminants, with subsequent accumulation in the sediments, which has the more far-reaching effect and which truly leads to a deterioration in environmental quality. Long-term bioaccumulation of metal and organic contaminants from the sediments does occur. The end-result can be a decrease in reproduction, increase in disease and poor health, and an increase in the occurrence of cancers and other abnormalities (e.g., Malins et al., 1984).
For those regions where fish or shellfish is a major source of protein, transmission of the contaminant through the food chain to human beings can be significant. This has led to recommended restrictions on the quantities of fish or shellfish consumed in order to reduce or limit the dietary intake of such chemicals. Human health is also affected by consumption of shellfish from areas contaminated by pathogens and bacteria. As aquaculture activities expand within coastal waters, this industry can also be affected by contaminants introduced from land-based sources.
To date, there is little international evidence for acute adverse effects from the disposal of dredged sediments beyond burial of the marine plants and animals or other resources on the sea floor. However, there is major international concern for unknown long-term chronic exposures and effects and therefore the need for a precautionary approach.
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Environmental Standards
Many of the regulatory constraints have been based on an extrapolation of the effects observed for in-situ contaminants to a potential effect at the open-water disposal site or from studies of a particular contaminant in a laboratory bioassessment.
The extrapolations have been based on a variety of techniques, including:
* Apparent effects threshold (measurement of contaminants in plants and animals from dredged areas and assessment of the biological effects)
* Sediment-biota partitioning equilibrium (comparison of contaminant concentration in the sediments to the concentration in plants and animals associated with the sediments)
* Sediment-water partitioning equilibrium (comparison of contaminant concentration in the sediments to the plants and animals in the overlying waters)
* Water quality objectives applied to sediment pore waters
The major deficiency in any of these techniques is the ability to separate matrix effects or the effect of multi-contaminants or the effect of the quality of the overlying waters from the effect of a particular contaminant. (Chapman, 1987).
There are two schools of thought as to the criteria to be used for open-water disposal. One school promotes the use of criteria based on the concentrations of various chemical compounds, where the regulated concentrations are based on laboratory or field data.
The alternative school promotes the use of detailed bio-assessment techniques in which various test animals or plants are exposed to the sediment in question. Effects such as bio-accumulation, mortality or sub-lethal effects are determined.
Many regulatory agencies are favouring a combination of both testing techniques with the use of chemical analyses to provide a "quick scan" of the sediments in question; if the measured concentrations are less than a specific criteria, the material poses no concern. If the analyses exceed a specific value, detailed bio-assessment is then undertaken to assess the biological response to the measured concentrations.
Pre-Proiect Characterization
The perception that all of the sediment to be dredged is seriously contaminated on the basis of one port area can be incorrect. Such an
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assumption can lead to significant difficulties in the port authority obtaining permission to dredge and also to dispose of the material in an economically viable fashion. An example of such a problem has occurred in such ports as: Oakland, California, USA; (World Dredging, 1989) and Seattle, Washington, USA; (Aggerholm, 1989).
For many ports and channels, the existing soil and sediment data characterization is often very poor, incomplete, outdated or does not take into consideration the most recent contaminants of concern.
Careful characterization of the nature of the sediments permits the whole port area (at various depths) to be classified into areas and volumes based on the disposal option most suitable (both environmentally and economically) for those particular materials.
Pre-project characterization can perform a very important role in the planning of the project and can ensure the best application of resources to achieve an environmentally and economically acceptable project. Detailed characterization permits the definition of:
* disposal options (see Section 5);
* quantities of materials in the various disposal options;
* the dredging equipment to be used in consideration not only of the disposal requirements, but also of transportation to the disposal options and to minimize sediment re-suspension and loss during dredging;
* monitoring programs at both the dredging and disposal locations;
* mitigative measures that may be required at the dredging or disposal sites;
The port or areas to be dredged can be divided or classified on the basis of the degree of sediment contamination. The definition and degree of contamination varies from nation to nation. It is often based on sediments described as "uncontaminated" or "background." For example, the following table gives sediment quality reference values which have been formally adopted for use in the Netherlands since 1987. Sediments lying below or equal to the "reference value" can, in general, be deposited on the land or in fresh or sea water without restriction. When the levels of dredged materials lie between the "reference value" and the "testing value"open water disposal is permitted under certain conditions. One of the conditions concerns the chemical changes in the particular contaminants being disposed that may take place in sea water. If the dredged materials have higher concentrations than the "testing value" they must be disposed in controlled containment facilities subject to constant monitoring.
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QUALITY STANDARDS FOR DREDGED MATERIALS IN THE NETHERLANDS
Name Reference
___ (mg/kg dry matter) _____________ ________-- Chromium Nickel Copper Zinc Cadmium Mercury Lead Arsenic Naphthalene Chrysene Phenanthrene Anthracene Fluoranthene Benzo(a) pyrene Benzo(a) anthracene Benzo(k) fluoranthene Indeno (1,2,3cd) pyrene Benzo (ghi) perylene Mineral Oil Total Octane, Heptane Pentachlorophenol Hexachlorobenzene PCB IUPAC-number: 28 52 101 118 138 153 180 Hexachlorocyclohexane Aldrin Dieldrin Endrin DDE Endosulphan Chlordane Heptachlorepoxide Hexachlorbutadiene
Value _______ 100 35 36
140 0.8 0.3
85 29 0.01 0.01 0.1 0.1 0.1 0.1 1
10 10 10 50 1 0.1 0.001
___
0.01 0.01 0.01 0.01 0.01 0.01
0.001 0.01 0.01 0.001 0.01 0.01 0.01 0.01 0.01
Testing Value w---- _____ 480 45 90
1000 7.5 1.6
530 85
_
0.8 0.8 0.8 2.0 0.8 0.8 0.8 0.8 0.8
3000
0.3 0.02
0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.02 0.04
0.04 0.02 0.02
0.02 0.02
Signalling Value
__________________----- 1000 200 400 2500
30 15
1000 150
(*) 3 0.2 3 0.2 3 0.2 7 1.2 3 0.2 3 0.2 3 0.6 3 0.2 3 0.2
5000
0.5 0.5
0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.5 0.5
0.5 0.5 0.5
0.5 0.5
NOTE: (*) General sediment environmental quality: current quality of sediments in relatively unpolluted regions.
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General guidance as to substances and levels of concern has been given in the LDC.3
3. INTERNATIONAL AGREEMENTS REGULATING POLLUTION
The oceans have long been considered to have a limitless capacity to receive and absorb all manner of wastes. Beginning in the 1950's, various scientists began to warn that this limitless capacity was running out and that the very survival of the marine environment was in doubt.
Many environmental groups began to demand that all waste disposal in the marine environment cease. The initial focus was on disposal of waste chemicals or incineration at sea of waste organo-halogen compounds (e.g., PCB). In particular the cases of industrial disposal from the Netherlands and Scandinavia4 led to various national proclamations against such practices. Subsequently the disposal of sewage sludges and the large volumes of dredged materials, particularly the materials from heavily industrialized urban centres (e.g., New York, USA), led to demands that these materials also not be permitted to be ocean disposed. Such demands were not limited to the oceans; for example, in the early 1970's both the United States and Canada limited the disposal of dredged sediments from the Great Lakes to confined shoreline or upland facilities with very little material being permitted to open-water sites.
The Conventions
Beginning with the Convention of 19786, the
Oslo Convention of 1974' and the Paris European nations sought to limit the input of
contaminants to the adjacent marine waters (the Baltic and North Seas in particular). The conventions addressed international waters. It was accepted that the disposal of dredged materials could occur provided the materials contained only "trace quantities of contaminants". Materials
w London Dumping Convention: See Section 3 and Attachment 1 to this Annex.
4/ "Stella Maris" incident, July 1971.
I/ The Oslo Commission was established by the Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft, commonly called the Oslo Convention, which was opened for signature on 15 February 1972. The Convention entered into force 6 April 1974. Ratified by 13 European countries.
u The Paris Commission was established by the Convention for the Prevention of Marine Pollution from Land-Based Sources, commonly called the Paris Convention, which was opened for signature 4 June 1974. The Convention entered into force 6 May 1978. Ratified by the EEC, Sweden, Norway and Iceland.
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which are primarily sand, gravel or rock, from areas of strong currents and are therefore not likely to contain significant concentrations of fine-grained contaminated sediments and which are intended for beach nourishment or other forms of shoreline protection should not have to be tested.
The intergovernmental convention on the dumpin of wastes at sea, commonly called the London Dumping Convention (LDC), $ adopted the general philosophy and has many similar articles of the Oslo Convention and applies to all international waters.
The LDC contains a series of Annexes8 listing a large number of chemicals and chemical compounds which are deemed hazardous or potentially hazardous and therefore worthy of regulation (e.g., mercury or organohalogen compounds). As with the earlier conventions, the LDC was designed primarily to regulate the dumping of chemical or industrial wastes in the marine environment.
The regulation of dredged materials and their disposal in the open ocean have revolved around the following terms:
* trace contaminants * significant amounts * rapidly rendered harmless * toxic * persistent * bio-accumulative
The question then arises as to what concentrations of such compounds can be considered "trace" or in such a form as to be "rapidly rendered harmless." The latter term arose from the chemical reactions that occur when various metal contaminated liquids are inter-mixed with seawater and the elevated pH and salinity rapidly create insoluble metal compounds. Concepts such as "rapidly rendered harmless" are not appropriate for such substances as organohalogen compounds which can be bio-accumulated at any concentration.
The LDC guidelines on dredged material disposal recommend:
* representative sampling * measuring the general characteristics
u The UK, with the UN, convened an Inter-Governmental Conference on the Convention on the Dumping of Wastes at Sea in November 1972 which adopted the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, the so-called London Dumping Convention. It entered into force on 30 August 1975. IMO was designated secretariat. By June 1989, 63 countries have ratified/acceded to the convention.
8/ See Attachment 1, Guidelines for the Application of the annexes to the Disposal of Dredged Material (Resolution LDC.23(10).
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* measuring the priority contaminants, and * biological testing, if necessary, to show that the material
can be dumped so as not to cause acute chronic effects or bio-accumulation in sensitive marine organisms typical of the disposal site
Subsequent to the LDC, various regional seas agreements (e.g., the Mediterranean Sea; United Nations, 1985) have been developed. These provide a facility to focus on particular problems for a region and take into account the particular ecosystem for that region (e.g., tropical waters versus North Atlantic waters).
Land-Based Sources of Contaminants and Contaminated Sediments
Most contaminants originate from land-based sources. Therefore environmental restrictions on the disposal of contaminated dredged materials does not address the source of the problem, but only a symptom. Control of land-based sources will play an important role in port development (UNEP, 1985; Jeftic, 1988) by decreasing the input of contaminants. To regulate at source, several nations recently established the Montreal Guidelines for Land-Based Pollutants. These guidelines express many of the same concerns for environmental impact as are now in place in such agreements as the London Dumping Convention and proposed to limit many of the same chemical substances. Over time sediments will become less contaminated. Regulatory agencies and Conventions will then be able to resume the permitting of open-water disposal of a larger proportion of the sediments.
Annlication to Dredged Materials
All of the agreements or conventions serve to regulate the introduction of chemicals to the aquatic environment. Although their prime focus is the regulation of waste chemicals and industrial materials, it is recognized that sewage sludges and dredged sediments can contain some of the chemical compounds of environmental concern. The efforts have then been to provide a regulatory regime which controls the introduction and dispersal of contaminant through dredged material disposal, while at the same time recognizing the economic needs for dredging to occur.
Many countries are now introducing policies in respect of the Brundtland Commission on Sustainable Development. This report recommended that development occur provided that the impact on the environment is taken into account and that all activities be undertaken to minimize environmental impacts. Increasingly, countries will incorporate these policies within their regulations with respect to dredging and dredged material disposal.
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4. EFFECT OF ENVIRONMENTAL RESTRICTIONS ON THE DREDGING AND TRANSPORTATION OF MATERIALS
Types of Restrictions
With the concern for health and environmental effects of dredging and dredged material disposal, environmental restrictions are playing a key role in all aspects of the project: 1) the selection of dredging equipment; 2) the timing of the project; 3) the transportation of the materials; and 4) the disposal option(s). As well, there could be a requirement for monitoring during the project and for mitigative measures to be undertaken as a result of the monitoring either during or subsequent to the project. The purpose of all environmental restrictions is to limit the impact of the project on both the adjacent waters and on the users (Man, marine plants and animals) of these waters. All dredging operations result in disturbance of the sediments to be removed from the dredging site. The primary concern is for the release and off-site transport of suspended solids and/or the associated contaminants (both chemical and biological) as a consequence of the disturbance. The various traditional dredging techniques disturb the sediments in different ways and to greater or lesser extents. New devices have been introduced in an attempt to completely eliminate the release of suspended solids.
Port Design
The need for dredging is usually driven by a socio-economic need to maintain and improve navigation or port facilities. However, poor port or facility design can actually increase the need for dredging. There are many examples where the placement of a facility, breakwaters, a harbour entrance, or the deepening of a channel has led to severe infilling by natural processes or has increased erosion and accretion processes along adjacent shoreline areas. Thus, the need for dredging can perhaps be reduced through hydraulic and engineering studies. Such studies can identify the direction of sediment transport and depositional nodes. Such studies would be particularly useful for projects where the siting of port facilities demands frequent maintenance dredging and where the material dredged is considered contaminated. Thus the studies to reduce the requirements for dredging could prove to be both economically and environmentally attractive.
Another alternative to "problem " harbours is to limit the dredging activities to specific harbours through regional planning. Harbours where there is minimum maintenance dredging requirements or where the over-lying waters are thoroughly flushed (e.g., by tidal actions), and the sediments are relatively uncontaminated should be developed rather than other ports which have polluted sediments which require frequent dredging to maintain navigation depths to reduce the environmental impact of port development. For example, ports that are served by feeder vessels typically need less water depths than ports catering to ocean going deep-draft vessels. Thus, if there are several ports available to a country for international maritime access, only those
- 64 -- FIGURE
TRACK CABLE ----__
----__ ----__
Land Based Dragline System
FIGURE 2
Bucket Ladder Dredger discharging into Barges
(Source: Port Autonome de Rouen, France)
- 65 - FIGURE 3
Grab or Clamshell Dredger discharging into Barges
FIGURE 4
Dipper Dredger discharging into Barges
(Source: Great Lakes Dredge and Dock Company, USA)
- 66 -
FIGURE 5
FKEG SRIDS OR LEGS -.-_ --
Back-Hoe Dredger discharging into Barges (Source: Taranaki Harbours Board, New Zealand)
FIGURE 6
Mud Cat Dredger pumping material via Pipeline
(Source: Ellicott Machine Corporation International, USA)
- 67 - FIGURE 7
Self Propelled Trailing Suction Hopper Dredger (Source: Wartsila Marine industries Inc., Finland)
FIGURE 8
I-
’ , I
Cutter Suction Dredger pumping material via Floating Pipeline
(Source: Zanen Verstoep NV, Netherlands)
- 68 -
ports which require the least dredging should be selected as ports for deep draft vessels - the remainder being served through transhipping at the deep-water ports.
DredPing Eauinment
Dredging equipment can be divided into two broad classifications: mechanical and hydraulic:
Mechanical dredgers are very similar to their dry-land counterparts. Material is excavated and usually placed in an intermediate transport mode. This can be scows, self-propelled or towed barges, trucks or even conveyor belts. Mechanical dredgers are typically used for materials where the physical nature requires and permits distinct excavation zones. Examples of mechanical dredgers are the dragline (Figure 1); ladder/bucket dredge (Figure 2); the clamshell (Figure 3); the dipper (Figure 4); and, the back-hoe (Figure 5).
Hydraulic dredgers suction the sediment via a fluidized slurry, typically with a 5-20X solids content. The suction action is augmented by the use of agitators, a cutter head or a trailing drag arm. The dredged material is pumped through a pipeline either directly into a disposal facility or into an internal or external hopper. When the material has to be transported long distances, pipelines with booster pumps are used. The various types of hydraulic dredgers are illustrated in Figures 6 to 8.
The physical and chemical nature of the sediments (e.g., coarse sand, fine-grained contaminated silt) controls the choice of dredging equipment through environmental concerns for release of material or associated contaminants during the actual dredging operation and through the specialized requirements for transport to the disposal site resulting from the dredging equipment used, the nature of the transit route and the nature of the disposal option and site. Mechanical dredgers tend to cause the least disturbance to the materials being dredged and thus the minimum release into the surrounding waters. In particular, the bucket ladder dredger may cause the least disturbance of all types of traditional equipment and because of this effect and the precision with which such equipment is able to operate, it is very often selected for maintenance dredging of port areas. The typical problem with hydraulic dredging is how to deal with huge volumes of water that are transported with the sediments. Frequently, special measures have to be taken to treat this water before it can be released.
Selection of Eauinment
Thus the selection of dredging equipment and procedure is not straight forward but becomes a compromise between six competing factors:
* environmental restrictions related to the nature of the materials and the associated contaminants.
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FILLING PHASE DISCHARGE PHASE
BOTTOM SEDIMENT
Operating Principle of the Pneuma Dredging System
COMPRESSED AIR
VACUUM PUMP DISCHARGE VAI VF
IR’PER LIMIT DETECTOR /
HYDRAULIC PRESSURE
/
II
SUCTION MOUTH
Operating Principle of the Oozer Pump Dredging System
(Source: Koba and Shiba, 1981)
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* physical nature of the materials to be dredged;
* cost and availability of equipment;
* disposal site location and limitations;
* wind, wave and sea conditions at the dredging site, in transit and at the disposal site;
* interference with other waterway users at the dredging site, in transit and at the disposal site (for both recreational and commercial users).
Environmental restrictions and concerns can affect the choice of equipment and operational procedures in three ways:
* Change to alternate equipment (e.g., Oozer pump' suction dredge to eliminate the release of materials at the point of excavation);
* Modifications to standard equipment or procedure (e.g, closed clamshell bucket dredge or trailing suction hopper dredge with no overflow);
* Change in equipment to accommodate disposal options (e.g., special off-loading equipment on a disposal barge to pump into a disposal facility);
It may be possible to undertake the dredging component in environmentally-sensitive areas without such changes, but, by designing into the project a variety of mitigative measures to ensure that the occurrence of an unacceptable impact is minimized while still permitting the use of available dredging equipment. Mitigative measures could include changes in the timing of a project (e.g., by season to avoid fish migrations or spawning or submerging pump-ashore pipelines or careful control of the movement of transit barges to avoid interference with commercial navigation); use of silt curtains; or use of specialized equipment for the most-contaminated surface materials followed by other equipment for less-contaminated sediment zones.
To be able to properly institute such mitigative measures typically requires an on-going or real-time monitoring program. Such programs usually entail regular sampling and analysis of turbidity or suspended solids; accumulation of sediments in sensitive areas; or monitoring for changes in dissolved oxygen or salinity (the result of release of gases from anoxic sediments or the intrusion of salt wedges into estuarine channels). Examples of such programs and the planning required can be found in Pequegnat et al. (1981)
2/ See Figure 9 for operating principle.
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5. REVIEW OF DISPOSAL OPTIONS
ODtiOn 'lbes
There are six disposal options:
1. no dredging and therefore no requirement for disposal;
2. open-water disposal: a) no containment b) contained
3. shoreline disposal: a) unconfined b) confined
4 upland disposal: a) unconfined b) confined
5. treatment of the contaminated sediments using hazardous wastes treatment processes;
6. using a combination of options 2 to 5;
As discussed in Section 4, there is usually a strong socio-economic reason for dredging, and thus the first option is rarely acceptable unless a port's vessel traffic can be changed to shallower drafts and the no dredging option would result in sustainable navigation. Within Options 2, 3 and 4, there are two sub-options: the first, representing an option for material that meets environmental specifications for contaminants; the second for material that contains contaminants in excess of guidelines.
Discussion of DiSDOSd ODtions
ODen-Water DisDosal: Uncontained open-water disposal has been the traditional method of dredged material disposal because it was the cheapest; there were few, if any, limitations on the location of the disposal site; the oceans were considered to have a limitless capacity to absorb waste materials; and, the disposal was considered to be simply "speeding up" natural processes of land-based soils being deposited into the oceans.
Figure 10 shows the open-water disposal process. Although much of the material does fall to the bottom within approximately the boundaries of the disposal site, strong upper water column or near-bottom currents can transport portions of the material off-site. This off-site transportation can lead to re-infilling of the dredged area, siltation of shellfish or fish spawning areas, or re-distribution of contaminated sediments.
FIGURE 10
HIGH DENSITY
RELEASE ZONE
ITY MATERIAL
POSAL SITE BOUNDARY
Releasing Dredged Material from a Hopper Dredger or Barge (Source: Pequegnat et al., 1980)
FIGURE 11
HVDRAUUC DWHARGE -PMLUTED WILDGED
MATERIAL NUTRIENTS
SEDIMENT VEGETATION lNTEAACTlON 7 INTERACTION 7
Cross Section of a Simple Confined Disposal Site
(Source. Chen et al., 1978)
- 73 - FIGURE 12
Open Water Capping of Polluted Sediments (Source: Pequegnat, 1981)
FIGURE 13
II-- SUBMERGED DIFFUSER
Submerged Difuser System for Placing Materials (Source: Shields and Montgomery, 1984)
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1‘ An innovative disposal technique, called the "thin layer" disposal method, is currently (June 1989) being tested by the U.S. Corps of Engineers at Mississipi Gulfport. The principle is to dispose of the contaminated dredged material by spreading it very thinly over a wide area. Various environmental agencies are associated with a one year experiment to assess the impact of spreading about 3 million cubic meters of dredged material in Mississipi Sound and monitoring the speed of recovery of the environment.
In some projects, it may be more cost-effective or more beneficial to use the dredged materials to limit shoreline erosion, for beach nourishment or as fill or construction materials. However, in these cases, the material has to have a physical and geotechnical nature that permits these uses.
Unconfined Disposal: For fine-grained materials, unconfined land or shoreline disposal has been less frequently employed. Some countries (e.g., The Netherlands) encouraged the use/disposal of dredged river or estuarine sediments on land areas to provide agricultural soils. However, as the understanding of contaminant chemistry and the existence of many trace organic contaminants increased, limitations had to be placed on this form of disposal. In many ports, land space is at a premium and the ability to site an upland or even a shoreline confined disposal facility is severely restricted or economically prohibitive.
Confined Disposal: As environmental concerns increased with all forms of waste disposal in the oceans, many nations actively considered forbidding all forms of ocean disposal, including that of dredged sediments. Placement of dredged materials, irrespective of the degree of contamination, was instituted in either shoreline or upland facilities (Figure 11). This process drastically increases disposal costs. Rough cost estimates from the U.S. Army Corps of Engineers and Public Works Canada suggest that unit costs for dredging and disposal in a confined disposal facility is probably at least five times as expensive as open-water disposal. This cost increase is due to the construction of the facility, the limitations on handling created by having to place the material within the facility and the long-term management and monitoring of the facility.
Onen-Water Disnosal with Capping: From numerous studies conducted by the U.S. Army Corps of Engineers (Gambrel1 et al., 1978), it was apparent that by maintaining contaminated anoxic sediments in a disposal site under the same conditions as existed at the dredge site, many of the contaminants, particularly the trace metals, remained chemically immobilized and thus had a low bioavailability.
To retain the physical-chemical regime in the dredged sediments and yet limit the interactions of the contaminated materials with the overlying waters and biota, the concept of open-water containment or capping (Figure 12) has been suggested (Shields, and Montgomery, 1984). In this form, contaminated material is buried under approximately one metre of "clean" sediment. Techniques have been developed for the
- 75 -
delivery of both the contaminated and cover materials (Figure 13) thereby improving the disposal techniques and reducing the amount of cover material required. Studies (O'Connor and O'Connor, 1983; Brannon et al., 1986; Truitt, 1986) have shown that such disposal does constrain the contaminated materials and limit interactions between the overlying waters, the biota and the contaminants. Recent studies carried out for the port of Baltimore, USA, suggest that the unit dredging costs including such disposal methods may more than double the costs of dredging with simple open-water disposal. Detailed comparative studies of upland confined, shoreline confined, and open-water disposal of highly contaminated sediments have recently shown that open-water disposal, with appropriate contfgls, can pose the least environmental impact considering all impacts.
Specialized Treatment: Where the quantities are relatively small, readily accessible within a port area and highly contaminated, another option is treatment or in-material immobilization. The use of treatment techniques to-date has been typically limited to projects where the level of contamination has required expensive or very limited disposal options and therefore a treatment technology is a financially-acceptable attractive alternative to the high costs of specialized disposal (McGrath, 1988; Allen, 1988). A variety of techniques have been proposed and tested on sediments (NRC, 1988; SAIC, 1985), but several drawbacks have been identified:
1) the original techniques were developed for handling dry contaminated soil not large quantities of wet dredged material;
2) the physical distribution of the materials to be dredged requires considerable handling to treatment facility;
3) the treated material still has to the treatment process must ensure meet environmental criteria;
4) the existing treatment techniques complex technology.
bring them to the
be disposed and therefore that the material will
are expensive and of a
Recently, a heat treatment and pelletizing process has been successfully tested in the Port of Hamburg (Kroning, 1988; Hampel et al., 1988). Here, to reduce the volume of material to be treated, all of the dredged material is subjected to a separation process. A centrifuge system first separates the course materials from the contaminated fine sediments. The fine sediments are then subjected to a de-watering process prior to stockpiling and then heat treatment. The water used for the centrifuge system and resulting from the dewatering is specially treated before discharge. The two drawbacks may be the
lOJ U.S. Corps of Engineers, Black Rock Harbor, Connecticut, study.
- 76 -
cost of the system and its complexity. The question of treatment technology versus simple disposal then becomes one of cost comparison between the two.
Another limitation in the use of treatment technologies is the complexity of the techniques. Many of the procedures for dredging and dredged material disposal, including the construction of confined disposal facilities have well established engineering protocols. Agencies, such as the U.S. Army Corps of Engineers, are continuously undertaking research and development projects to refine techniques and revise procedural manuals. The problem of trained staff and the ability to procure the equipment could be a major detraction to the introduction and use of such processes in less developed countries.
Minimizing Costs Through Careful Planning
Careful characterization of the sediments proposed for dredging, may identify Option 6, with a combination of options, as the most acceptable, taking into account both environmental and economic considerations. Under this scenario, all of the port area to be dredged, irrespective of the timing of the separate projects, is carefully assessed and the material characterized as to its physical and chemical natures. Quantities that are clearly contaminated and of poor geotechnical properties are identified for specialized containment or even treatment; as materials are identified as being less-contaminated, less stringent options for disposal are identified. This process has proven very successful in the Port of Rotterdam (van Bochoven et al., 1988). The port of Hamburg is testing the next stage in which the materials identified as being so contaminated as to warrant specialized containment are physically sorted through either natural separation through settling or through the use of a hydrocyclone. Only the fine- grained materials, with which the contaminants are primarily associated, require treatment or containment. The remaining materials, after testing, can then be disposed via other options. This further reduces the volume of contaminated material to be disposed in a specialized manner.
The end result of choosing the multi-option process is to reduce and contain the costs of the project while maintaining the proper environmental controls.
Having identified those areas which are severely or moderately contaminated, policies can be drafted both to limit the requirements for dredging and thus disposal for those areas and to limit the sources of contamination, typically from land-based sources (both riverine and outfalls within the port). In the application of any disposal option, the long-term costs associated with the option have to be considered within the short and long-term costs of the project and the cost/benefit ratio.
- 77 -
A recent, March 1989, survey11 of USA maintenance materials disposal on an annual volume basis showed the disposal options:
Ocean open-water 22.5% Coastal open-water 20.0% Confined up-land 30.5% Containment islands 6.5% Beneficial uses 20.4%
dredging following use of
The beneficial uses were mostly for beach nourishment. Twelve ports, 24% of the survey, reported that they had dredged material that required special care in disposal and 72% that they would face much greater difficulties in finding disposal sites in the future.
6. RECOMMENDATIONS AND CONCLUSIONS
Recommendations
The World Bank through its lending operations is associated with many dredging projects for infrastructure developments or improvements. Recognizing the potential environmental impact of dredging operations, it is essential that in preparing and executing projects that extreme care is exercised to minimize or avoid detrimental impacts.
The first step in the preparatory process is to determine if any of the materials to be dredged are contaminated and, if so, are they contaminated to an extent which might cause pollution. In areas where contaminated sediments are suspected to exist, tests should be carried out in typically representative areas and depths to characterize the degree of contamination in the materials to be dredged. This does not mean that each sample should be subjected to exhaustive organic and inorganic chemical analyses to establish the presence and the concentrations of a wide-ranging list of compounds since knowledge of local discharge/disposal practices can be used to make a list of "most probable to occur" substances. Selective analysis can be used to assess the potential for pollution effects. Alternatively, the substances shown in Annexes I and II of the London Dumping Convention (see attachment 1) and also the Table on page 9, Section 2, could be used as a list of compounds to be investigated. If the results of these tests indicate that there are sediments which have sufficiently high levels of contamination that they would probably result in harmful effects (i.e. pollution) when disposed in open-water or unconfined upland disposal sites then a carefully prepared action plan must be undertaken. Concentrations that define "contaminated" are still not universally accepted. As a guide, the LDC has defined concentrations for some trace metal contaminants; the North American and European countries are now attempting to define concentrations for organic compounds. Attachment 2
11/ Dredged Material Disposal Survey: American Association of Port Authorities (AAPA) March 1989; 7 pages plus annexes.
- 78 -
of this report contains the LDC Guidelines to the Disposal of Dredged Materials which contains very useful information on how the problem should be addressed.
The second step is to carry out a detailed characterization of all of the sediments within the port or harbour confines and to depths which are likely to be disturbed or exposed by the proposed dredging. This detailed characterization will enable the port areas to be divided into dredging zones each of which may require different types of dredging techniques and methods of disposal. The objective of this characterization program should be to reduce the volumes of dredged materials which are difficult to dispose of to a minimum. It is likely that the design concept of the proposed project may have to be amended at this stage to avoid dredging excessive volumes of polluted materials. Associated with this step should be the commencement of a program to eliminate the sources of the contaminants. Although even instant elimination of the land-based sources of contamination would still take a long period for the polluted sediments to be restored through natural processes to levels "acceptable" for open-water disposal, it is essential that action be taken now to control the sources based on the Montreal Guidelines on Land Based Sources of Marine Pollution. This may be difficult to put in place since the sources could be upstream in another country or associated with a multitude of long established industries and practices which cannot be corrected overnight and which will require very considerable investment - often in foreign exchange.
The third step is to select the type of dredging equipment to be employed for each zone - using specialist equipment for the very polluted sediments to avoid excessive disturbance and re-suspension.
The fourth step is to select the method of disposal to be used for the materials resulting from each zone using the various options available. The system for transportation of the dredged materials to the eventual disposal site must also be considered and a selection made.
The fifth step concerns the disposal. If disposal in open-water is proposed, the existing regulatory conventions must be observed, with appropriate sediment and disposal site option testing carried out to predict the likely effects of the disposal option. The studies and tests to be carried out may include:
* the general requirements of the LDC * chemical and physical analysis * biological testing * formulation of the impact hypothesis * the development and use of quality standards
Considerable information is readily available on the objectives and scope of these studies and tests from sources such as IMO and well established national laboratories. It is important to appreciate that open-water ocean disposal of uncontaminated dredged materials can also cause major environmental impacts through, for example, suspended
- 79 -
sediments reducing light penetration essential for corals or natural gravel beds used for spawning or as a habitat by certain marine species becoming covered by clays or silts.
If confined upland disposal is selected, the facility will require careful design, construction and monitoring. In particular, aspects to be considered will possibly include: lining the containment basin with impermeable materials to avoid leaching into the underlying aquifers; treatment of the run-off water before returning it to the regime; and, the final land use when the containment basin is filled.
It is important to put in place adequate long term monitoring procedures for all of the dredging and disposal systems, and this is particularly important if polluted dredged materials are involved. Apart from chemical/physical testing, biological testing is extremely important - especially testing for bio-accumulation using a fish, a crustacean and a mollusc typical of the disposal site.
Conclusions
Although it is difficult to place a value on "good environment", increasing public concern for the impact on the environment and the potential increase in risk to human health or foodstuffs, has led to the demand for increased environmental control. As there is usually a socio-economic need for dredging and port construction, viable options for disposal must be considered.
Several governments have proposed restricting all disposal to confined shoreline or upland facilities thereby limiting the disposal of any wastes in the marine environment. The high costs of such disposal, coupled with scientific studies to show that the chemistry of open-water disposal better immobilized the contaminants compared to shoreline or upland facilities, has led to suggestions for a return to open-water disposal, but with containment achieved through capping.
An alternative to disposal and containment is the treatment of the contaminated sediments using techniques established for treating hazardous materials (e.g., leaching/washing or heat fusion). Many of these techniques have been developed from the treatment of contaminated soils or hazardous wastes. The primary drawback is the cost and the technological sophistication of the techniques.
Many of the complaints associated with environmental restrictions on dredged material disposal are related to the increase in cost for disposal compared to a pre-regulation period. Since the public demand for regulations to reduce environmental impact and heath hazards is increasing, it is in the best interests of the project to determine other methods of undertaking the project in a cost-competitive fashion while still meeting all environmental regulations. The cost for dredging and having to dispose of the materials in an upland containment basin are likely to increase the unit costs of dredging by a factor of five times. If it is possible to dispose of the materials in an open-
- 80 -
water site - including capping - the unit costs may be increased by a factor of about two and a half provided the site is not too far distant.
Although the no-dredging option is typically unacceptable for various socio-economic reasons, the undertaking of engineering studies to limit the source of siltation of the port or the need to dredge can be very cost effective. Such studies can lead to the construction of facilities or changes to existing structures which will help to minimize the requirements for dredging contaminated sediments and thus reduce a difficult disposal problem.
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7. BIBLIOGRAPHY
Allen, D. 1988. Bench-/Pilot-Scale Studies to Support the Evaluation of Remedial Alternatives for the PCB-Contaminated Sediments in New Bedford Harbour, Massachusetts. Presentation at the Technology Transfer Symposium for the Remediation of Contaminated Sediments in the Great Lakes. International Joint Commission, Windsor, Ontario, Canada.
Aggerholm, D.A., 1989. Sediment Regulation in Puget Sound. (99-109) Proceed. XII World Dredging Congress, Orlando, Florida, U.S.A.
Brannon, J.M., R.E. Hoeppel, T.C. Sturgis, I. Smith, Jr., and D. Gunnison. 1986. Effectiveness of Capping in Isolating Dutch Kills Sediment from Biota and the Overlying Water. Dredging Operations Technical Support Program Miscell. Paper D-86-2. U.S. Army Corps of Engineers, Waterways Experiment Station.
Chapman, G.A., 1987. Establishing Sediment Criteria for Chemicals-Regulatory Perspective. (355-377) in Fate and Effects of Sediment-Bound Chemicals in Aquatic Systems. (K.L. Dickson, A.W. Maki and W.A. Brungs, eds.) Pergamon Press.
Gambrell, R.P.R.A. Khalid, and W.H. Patrick,Jr., 1978. Disposal Alternatives for Contaminated Dredged Materials as a Management Tool to Minimize Adverse Environmental Effects. Dredged Material Research Program. Tech. Rept. DS-78-8. U.S. Army Corps of Engineers, Waterways Experiment Station.
Hampbel, H.J., D. Hankel, and H. Kroning. 1988. Thermal Treatment of Dredged Material.
Jeftic, L. 1988. UNEP Guidelines for the Protection of the Marine Environment Against Pollution from Land-based Sources: Their Implementation in the Mediterranean. Proceedings of the Canadian Conference on Marine Environmental Quality. 28 Feb. - 3 March, Halifax, N.S. Canada. (P. Wells, and J. Gratwick, eds.).
Koba, H.Y. and Shiba, T. 1981. Test Dredging of Bottom Sediments in Osaka Bay. Presentation at the 7th U.S.-Japanese Experts Meeting on the Management of Bottom Sediments Containing Toxic Substances. Proceedings published by the U.S. Army Corps of Engineers Water Resources Support Centre.
Kroning, H., 1988. First Practical Experience with the Industrial-Sea'.- Metha II Plant for the Mechanical Separation of Dredged Material From the Hamburg Harbour.
Lazor, R. 1987. Comparative Studies of Disposal of Dredged Materials from Black Rock Harbour, Connecticut. Presentation made at the 7th International Ocean Disposal Symposium, Wolfville, N.S. Canada.
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MacKnight, S., 1984. Background Document for the Preparation of Sediment Sampling Guidelines for the Characterization of Dredged Sediments Under the Ocean Dumping Control Act. Report of OceanChem Ltd. to Environment Canada.
Malins, D.C., B.B. McCain, D.W. Brown, S.-L. Chan, M.S. Myers, J. T. Lnadahgl, P.G. Prohaska, A.J. Friedman, L.D. Rhodes, D.G. Burrows, W.D. Gronlund, and H.O. Hodgins. 1984. Chemical Pollutants in Sediments and Diseases of Bottom-Dwelling Fish in Puget Sound, Washington. Environmental Science and Technology, 18, 705-713.
McGrath, R., 1988. PCB-contaminated Sediments in New Bedford Harbour, Massachusetts: Application of a Modeling Approach to Support Selection of Remedial Alternatives. Presentation at the Technology Transfer Symposium for the Remediation of Contaminated Sediments in the Great Lakes. International Joint Commission, Windsor, Ontario, Canada.
NRC (National Research Council). 1988. Draft Proceedings of a Contaminated Marine Sediments Symposium/Workshop sponsored by the Marine Board, Committee on Contaminated Marine Sediments. (Tampa, Florida, June, 1988).
Q#Connor, J. and S.G. O'Connor. 1983. Evaluation of the 1980 Capping Operations at the Experimental Mud Dump Site, New York Bight Apex. Dredging Operations Technical Support Program Tech. Rept. D-83-3. U.S. Army Corps of Engineers, Waterways Experiment Station.
Oslo and Paris Commissions. 1984. The First Decade: International Co-operation in Protecting Our Marine Environment. Oslo and Paris Commissions. (377pg.)
Palermo, M.R., N.R. Francingues, C.R. Lee and R.K. Peddicord. 1986. Evaluation of Dredged Material Disposal Alternatives: Test Protocols and Contaminant Control Measures. (493-505) Proceed. XI World Dredging Congress, Brighton, U.K.
Pequegnat, W.E., L.H. Pequegnat, B.M. James, E.A. Kennedy, R.R. Fay, and A.D. Fredericks. 1981. Procedural Guide for Designation Surveys of Ocean Dredged Material Disposal Sites. Technical Report EL- 81-1 U.S. Army Corps of Engineers, Waterways Experimental Station.
SAIC (Science Applications International Corp.). 1985. Removal and Mitigation of Contaminated Sediments. Report to the U.S. Environmental Protection Agency, Hazardous Waste Engineering Research Laboratory.
- a3 -
Shields, F.D. and R.L. Montgomery. 1984. Fundamentals of Capping Contaminated Dredged Material. (446-460) In, Dredging and Dredged Material Disposal. (R.L. Montgomery and J.W. Leach, eds.) Amer. Sot. Civil Engineering.
Truitt, C. 1986. The Duwamish Waterways Capping Demonstration Project: Engineering Analysis and Results of Physical Monitoring. Long-term Effects of Dredging Operation Program Tech. Rept. D-86-2. U.S. Army Corps of Engineers, Waterways Experiment Station.
United Nations. 1982. Convention for the Protection of the Mediterranean Sea Against Pollution and its Related Protocols. (45 pages).
UNEP, 1985. (United Nations Environmental Programme) Ad hoc Working Group of Experts on the Protection of the Marine Environment against Pollution from Land-based Sources. (UNEP/WG.120/3, 19 April). Also published in Environmental Policy and Law, 14/2/3, 1985.
Van Bochoven, G., C. Boodt, J.M. de Bruyne, H.J. de Haan, J.A. Hellema,
World
G. Ottevanger, W.D. Rokosh, C. Van-Rijt, R.H.W. VanVechgel, T. Vellinga, and M. Veltman. 1988. Minimizing the Cost of Maintenance Dredging. PIANC Bulletin, 63, 51- 94.
Dredging and Marine Construction. May/June, 1989. Oakland Disposal Option Proposed. (P. 6).
. ,*
Attachments I and II
London Dumping Convention
AlTACHMENT 1
London Dumping Convention
Annex 1
1 Qrganohalogen compounds.
2 Mercury and mercury compounds.
3 Cadmium and cadmium compounds.
4 Persistent plastics and other persistent synthetic materials, for example, netting and ropes, which may float or may remain in suspension in the sea in such a manner as to interfere materially with fishing, navigation or other legitimate uses of the sea.
“5 Crude oil and its wastes, refined petroleum products, petroleum distillate residues, and any mixtures containing any of these, taken on board for Lhe purpose of dumping.
6 High-level radio-active wastes or other high--level radio-active matter, defined on public health, biological or other grounds, by the competent international body in this field, at present the International Atomic Energy Agency 9 as unsuitable for dumping at sea.
7 Haterials in whatever form (e.g. solids, liquids, gases or in a living state) produced for biological and chemical warfare.
8 The preceding paragraphs of this Annex do not apply to substances which are rapidly rendered harml.ess by physical., chemical or biological processes in the sea provided they do not:
(i) make edible marine organisms unpalatable, or
(ii) endanger human health or that of domestic animals.
The consultative procedure provided for under Article XIV should be followed by a Party if there is doubt about the harmlessness of the substance.
9 This Annex does not apply to wastes or other materials (e.g. sewage sludges and dredged spoils) containing the matters referred to in paragraphs l-5 above as trace contaminants. Such wastes shall be subject to the provisions of Annexes II and III as appropriate.
* Paragraph 5 was amended by the FifLh Consultative Meeting of Contracting Rarties in 1980. The original text of paragraph 5 reads as follows:
“5 Crude oil, fuel oil, heavy diesel oil, and lubricating oils, hydraul ic fluids, and any mixtures containing any of these, taken on board for the purpose of dumping.”
The amendment entered into force on 11 March 1981.
-2-
**lo Paragraphs 1 and 5 of this Annex do not apply to the disposal of wastes or other matter referred to in these paragraphs by means of incineration at sea. Incineration of such wastes or other matter at sea requires a prior special permit. In the issue of special permits for incineration the Contracting Parties shall apply the Regulations for the Control of Incineration of Wastes and Other Matter at Sea set forth in the Addendum to this Annex (which shall constitute an integral part of this Annex) and take full account of the Technical Guidelines on the Control of Incineration of Wastes and Other Matter at Sea adopted by the Contracting Parties in consultation.
** Paragraph 10 was added to the original text by the Third Consultative Meeting of Contracting Parties in 1978. The amendment entered into force on 11 March 1979.
Annex II
The following substances and materials requiring special care are listed for the purposes of Article VI(l)(a).
A Wastes containing significant amounts of the matters listed below:
arsenic 1 lead 1 and their compounds copper 1 zinc 1 organosilicon compounds cyanides fluorides pesticides and their by-products not covered in Annex I.
B In the issue of permits for the dumping of large quantities of acids and alkalis, consideration shall be given to the possible presence in such wastes of the substances listed in paragraph A and to the following additional substances:
beryllium 1 chromium ) nickel 1 vanadium )
and their compounds
C Containers, scrap metal and other bulky wastes liable to sink to the sea bottom which may present a serious obstacle to fishing or navigation.
D Radio-active wastes or other radio-active matter not included in Annex I. In the issue of permits for the dumping of this matter, the Contracting Parties should take full account of the recommendations of the competent international body in this field, at present the International Atomic Energy Agency.
*E In the issue of special permits for the incineration of substances and materials listed in this Annex, the Contracting Parties shall apply the Regulations for the Control of Incineration of Wastes and Other Matter at Sea set forth in the Addendum to Annex ‘I. and take full account of the Technical Guidelines on the Control of Incineration of Wastes and Other Matter at Sea adopted by the Contracting Parties in consultation, to the extent specified in these Regulations and Guidelines.
**(F Substances which, though of a non-toxic nature, may become harmful due to the quantities in which they are dumped, or which reduce amenities.
Yc Additional paragraph adopted as an amendment Meeting of Contracting Parties in 3.978, The on 11 March 1979.
** Additional paragraph adopted as an amendment Meeting of Contracting Parties in 1980. The on 11 March 1981.
are liable to seriously
by the Third Consultative amendment entered into force
by the Fifth Consultative amendment entered into force
Annex III
Provisions to be considered in establishing criteria governing the issue of permits for the dumping of matter at sea, taking into account Article TV(Z), include:
A- Characteristics and composition of the matter
1 Total amount and average composition of matter dumped (e.g. per year).
2 Form e.g. solid, sludge, liquid or gaseous.
3 Properties: physical (e.g. solubility and density), chemical and biochemical (e.g. oxygen demand, nutrients) and biological (e.g. presence of viruses, bacteria, yeasts, parasites).
4 Toxicity.
5 Persistence: physical, chemical and biological.
6 Accumulation and biotransformation in biological. materials or sediments.
7 Susceptibility to physical., chemical. and biochemical changes and interaction in the aquatic environment with other dissol.ved organic and inorganic materials.
8 Probability of production of taints or other changes reducing marketability of resources (fish, shellfish, etc.).
B- Characteristics of dumping site and method of deposit
1 Location (e.g. co-ordinates of the dumping area, depth and distance from the coast), location in relation to other areas (e.g. amenity areas, spawning, nursery and fishing areas and exploitable resources).
2 Rate of disposal. per specific period (e.g. quantity per day, per week, per month).
3 Methods of packaging and containment, if any.
4 Initial dilution achieved by proposed method of release.
5 Dispersal characteristics (e.g. effects of currents, tides and wind on horizontal transport and vertical mixing).
6 Water characteristics, (e.g.temperature, pH, salinity, stratification, oxygen indices of pollution - dissolved oxygen (DO), chemical oxygen demand (COD), biochemical. oxygen demand (ROD) - nitrogen present in organic and mineral form including ammonia, suspended matter, other nutrients and productivity).
-2-
7 Bottom characteristics (e.g. topography, geochemical and geological characteristics and biological productivity).
8 Existence and effects of other dumpings which have been made in the dumping area (e.g. heavy metal. background reading and organic carbon content).
9 In issuing a permit for dumping, Contracting Parties should consider whether an adequate scientific basis exists for assessing the consequences of such dumping, as outl.ined in this Annex, taking into account seasonal variations.
C- General. considerations and conditions
1 Possible effects on amenities (e.g. presence of floating or stranded material, turbidity, objectionable odour, discolouration and foaming).
2 Possible effects on marine life, fish and sheAlfish culture, fish stocks and fisheries, seaweed harvesting and culture.
3 Possible effects on other uses of the sea, (e.g. impairment of water quality for industrial use, underwater corrosion of structures, interference with ship operations from floating materials, interference with fishing or navigation through deposit of waste or solid objects on the sea floor, and protection of areas of special importance for scientific or conservation purposes).
4 The practical availability of alternative land-based methods treatment, disposal. or elimination, or of treatment to render the harmful. for dumping at sea.
of matter less
ANNEX 6
RESOLUTION LDC.32(11)
AMENDMENTS TO THE GUIDANCE FOR THE APPLICATION OF ANNEX IT1
(resolution LDC.17(8))
(LDC 31/14, annex 4)
THE ELEVENTH CONSIJLTATIVE MEETING,
RECALLING Article I of the Convention on the Prevention of Marine
Pollution by Dumping of Wastes and Other Matter, which provides that
Contracting Parties shall individually and collectively promote the effective
control of al.1 sources of pollution of the marine environment,
RECALLING FURTHER that amendments to Annex III had been adopted by
resolution LDC.26(10) concerning problems which had been encountered with
ill-defined wastes that had been proposed for disposal at sea, and the impact
of such wastes to marine life and human health,
EMPHASIZING the need that, in accordance with Annex III to the
Convention, Contracting Parties, before considering the dumping or
incineration of wastes at sea, should ensure that every effort has been made
to determine the practical availability of alternative land-based methods of
treatment, disposal or eJ.imination of the wastes concerned,
NOTING the discussion which took place within the Scientific Group on
Dumping on the need for Contracting Parties, when establishing criteria
governing the issue of permits for the dumping of matter at sea, to be guided
in their application of the provisions of Annex III to the Convention,
HAVING CONSIDERED the Guidelines for the Implementation and Uniform
Interpretation of Annex III to the London Dumping Convention (resolution
LDC.17(8)) and the proposed amendments to these guidelines prepared by the
Scientific Group on Dumping,
ANNEX 6 Page 2
1 ADOPTS amendments to sections A4 to Ad, A9 and C4 of the Guidelines for
the Implementation and IJniform Interpretation of Annex III to the London
Dumping Convention,
2 RESOLVES that Contracting Parties to the Convention shall take full
account of the amended Guidelines for the Implementation and Uniform
‘/ Interpretation of Annex III as shown in annex when considering the factors set
forth in that Annex prior to the issue of any permit for disposal and
incineration of matter at sea.
ANNEX 6 Page 3
ANNEX
GIJTDELINES FOR THR IMPLEMENTATION AND IJNIFORM INTERPRETATION OF ANNEX III* TO THE LONDON DUMPING CONVRNTlON
Article W(2): Any permit shall be issued only after careful consideration of all the factors set forth in Annex III, including prior studies of the characteristics of the dumping site, as set forth in Sections R and C of that Annex.
ANNEX III: Provisions to be considered in establishing criteria governing the issue of permits for the dumping of matter at sea, taking into account Article W(2), include :
Interpretation:
Each authority or authorities designated in accordance with Article VI
for the issue of general and special permits for the disposal of wastes and
other matter at sea shall, when considering a permit application, carefully
study all the factors set out in Annex III. This includes the establishment
of procedures and criteria for:
1 deciding whether an application for sea disposal should be pursued
in the light of the availability of land-based disposal or treatment
methods ;
2 sel.ecting a sea disposal site, including the choice and collection
of relevant scientific, data to assess the potential hazards to human
health, harm to living resources and marine life, damage to
amenities or interference with other legitimate uses of the sea;
* For the disposal at sea of radioactive wastes additional requirements recommended by the IAEA have to be taken into account (INFCIRC/205/Add.l/Rev.l). For the control of incineration of wastes at sea specific site selection criteria have been established (Regulation 8 of Addendum to Annex I).
ANNEX 6 Page 4
3 choosing appropriate disposal methods and conditions;
4 developing an appropriate monitoring programme.
The above mentioned criteria should enable permit applications to be
effectively assessed and likely environmental hazards to be evaluated.
A- CHARACTERISTICS AND COMPOSITION OF THE MATTER
1 Total amount and average composition of matter [to be1 dumped
(e.g. per year).
2 Form, e.g. solid, sludge, liquid, or gaseous.
3 Properties: physical (e.g. solubility and density), chemical
and biochemical (e.g. oxygen demand, nutrients) and biological
(e.g. presence of viruses, bacteria, yeasts, parasites).
Interpretation:
In order to assess environmental transport and fate, including potential
effects on water quality and biota, the total amount of wastes proposed to be
dumped within a time period, and the physical, chemical and biological
composition of the waste should be known. The first step for the
characterization of a waste or other matter proposed for dumping at a site
should be the collection of existing data on the waste composition or a waste
analysis.
This should not mean that every waste should be subjected to exhaustive
chemical analysis to establish the concentrations of a standard wide--ranging
list of chemical elements or compounds. Knowledge of the raw materials and
production processes used may often provide a key to the probable composition
of the waste. A selective analysis may then be sufficient for a preliminary
assessment. As a minimum, it should be established whether any Annex I or
Annex II materials are present.
ANNEX 6 Page 5
The analysis should include appropriate measurements of the composition
of major components. In cases where anthropogenic chemicals of high toxicity
are known or suspected to he involved, those minor components which are
reasonably identifiable should be measured.
In addition data should, as appropriate, be obtained on physical,
chemical and biological properties of the waste or other matter, such as:
- Solubility
- Percent solids
- Density (specific gravity) of bulk matter, its liquid and particle
phases
- Grain size fractions
fractions of dredged
- PH
of total solid phase (e.g. clay-silt/sand-gravel
material)
- Biochemical oxygen demand (BOD)
- Chemical oxygen demand (COD)
- Nutrients
- Microbiological components.
4 Toxicity,
5 Persistence: physical., chemical and biological,
6 Accumulation and biotransformation in biol.ogical. materials or
sediments.
Interpretation:
If the chemical analysis of the wastes shows the presence of
substances whose biological effects are not well known, or if there is any
doubt as to the exact composition or properties of the waste, if may be
necessary to carry out suitable test procedures for toxicity, persistence,
bioavailability and bioaccumulation, which may include the following:
ANNEX 6 Page 6
1 acute toxicity tests on phytoplankton, crustaceans or molluscs,
fish, or other such organisms as may be appropriate;
2 chronic toxicity tests capable of evaluating long-term sublethal
effects, such as bioassays covering an entire life cycle;
3 tests to determine the potential for bioavailability and
bioaccumulation of the substances contained in the waste and, if
appropriate, the potential for eventual elimination. The test
organisms should be those most likely to bioaccumulate the
substances concerned; and
4 test for determining the persistence of substances contained in
the waste. The potential for degradability of these substances
shouJ.d be determined using bacteria and water typical of the
proposed dumping site. The tests shou1.d attempt to reflect the
conditions at the proposed dumping site.
If appropriate, the test procedures described above should be carried
out separately with the solid, suspended and/or liquid phases of wastes
proposed for sea disposal.
A number of substances, when entering the marine environment, are
known to be altered by biological processes to more toxic substances. This
should be taken into particular account when the various tests mentioned
above are performed .
ANNEX 6 Page 7
7 Susceptibility to physical, chemical and biochemical changes and interaction in the aquatic environment with other dissolved organic and inorganic materials
Interpretation:
Substances introduced into the sea may be rapidly rendered harmless by
physical, chemical and biochemical processes but others may be changed to
products with more hazardous properties than those of the original
substances. In these latter cases, it may be appropriate to carry out the
tests outlined in paragraph A6 above with the anticipated products.
8 Probability of production of taints or other changes reducing marketability of resources (fish, shellfish, etc.).
Interpretation:
In evaluating the possible effects of the waste concerned on marine
biota, particular attention should be paid to those substances which are known
to accumulate in marine organisms with the result that seafood is tainted and
rendered unpalatable. In many cases there might be a suspicion about the
tainting property of a substance without the availability of firm data. In
these cases a taste panel will have to determine threshold limits, if any, of
the tainting properties of the substance concerned.
“Other changes reducing the marketability of resources** referred to in
paragraph 8 of Section A include discolouration of fish flesh, and fish
diseases such as fin rot and tumours.
ANNEX 6 Page 8
__
9 In issuing a permit for dumping, Contracting Parties should consider whether an adequate scientific basis exists concerning characteristics and composition of the matter to be dumped to assess the impact of the matter to marine life and to human health.”
Interpretation: “_lyl__ -_
In considering disposal at sea of ill-defined wastes or waste mixtures
from multiple sources, every effort should be made to obtain data on their
chemical, physical and biological characteristics to assess their
environmental transport, Sate and effects. If a waste is so poorly
characterized that proper assessment (using the foregoing guidelines) cannot
be made of its potential impacts in the environment, then that waste should
not be dumped at sea.
R- CHARACTERISTICS OF DUMPING SITE AND METHOD OF DEPOSIT
Matters relating to dumpsite selection criteria are addressed in greater detail in a study prepared by GESAMP** (Reports and Studies No.16: Scientific Criteria for the Selection of Waste Disposal Sites at Sea, IMO 3.982) which should be considered in conjunction with these guidelines.
1 Location (e.g. co-ordinates of the dumping area, depth and distance from the coast), location in relation to other areas (e.g. amenity areas, spawning, nursery and fishing areas and exploitable resources).
Interpretation: --
Rasic site characterization information to
authorities at a very early stage of assessment
x The inclusion of paragraph 9 in section A in principle and the Twelfth Consultative its formal adoption.
** IMO/FAO/UNESCO/WMO/WHO/IAEA/UNEP Joint Scientific Aspects of Marine Pollution.
be considered by national
of a new site should include
of Annex III has been approved Meeting has been designated for
Group of Experts on the
ANNEX 6 Page 9
the co-ordinates of the dumping area (latitude, longitude), as well as
its location with regard to:
- distance to nearest coastline
- recreational areas
- spawning and nursery areas
- known migration routes of fish or marine mammals
- sport and commercial fishing areas
- areas of natural beauty or significant cultural or historical
importance
- areas of special scientific or biological importance (marine
sanctuaries)
- shipping lanes
- military exclusion zones
- engineering uses of seafloor (e.g. potential or ongoing seabed mining,
undersea cables, desalination or energy conversion sites).
2 Rate of disposal per specific period (e.g. quantity per day, per week, per month).
Interpretation:
Although the amounts of matter to be dumped (e.g. per year) are
considered under paragraph Al above, many operations, e.g. those related to
dredging, are of shorter periods. In order to assess the capacity of the area
for receiving a given type of material the anticipated loading rates
(e.g. per day) or in the case of existing sites, the actual loading rates
(frequency of operations and quantities of wastes or other matter disposed of
at each operation per time period) should be taken into consideration.
ANNEX 6 Page 10
3 Methods of packaging and containment, if any.
4 Initial dilution achieved by proposed method of release.
IIterpretation:
The data to be considered under this item should include information on:
type, size and form of packaging and containment units
presence of any Annex 1 or Annex II substances as packaging material
or in any matrix that might be used
marking and labelling of packages
disposal method (e.g. jettisoning over ship’s side; discharge of
liquids and sludges through pipes, pumping rates, number and location
of discharge pipe outlets (under or above waterline, water depth),
etc.). In this connexion the length and speed of the vessel when
discharging wastes or other matter should be used to establish the
initial dilution.
5 Dispersal characteristics (e.g. effects of currents, tides and wind on horizontal transport and vertical mixing).
6 Water characteristics (e.g. temperature, pH, salinity, stratification, oxygen indices of pollution - dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (ROD) - nitrogen present in organic and mineral form including ammonia, suspended matter, other nutrients and productivity).
Interpretation:
For the evaluation of dispersal characteristics data should be obtained
on the following:
- water depths (maximum, minimum, mean)
- water stratification in various seasons and weather conditions (depth
and seasonal variation of pycnocline)
ANNEX 6 Page 11
- tidal period, orientation of tidal. ellipse, velocities of minor and
major axis
- mean surface drift (net): direction, velocity
- mean bottom drift (net): direction, velocity
- storm (wave) induced bottom currents (velocities)
- wind and wave characteristics, average number of storm days per year
- concentration and composition of suspended solids.
Where the chemical composition of the waste warrants, it may be
appropriate to evaluate pH, suspended solids, persistent organic chemicals,
metals, nutrients and microbiological components. BOD and COD or organic
carbon determinations in the suspended or dissolved phase, together with
oxygen measurements, may also be appropriate where organic wastes or
nutrients are concerned.
7 Bottom characteristics (e.g. topography, geochemical and geological characteristics and biological productivity).
Interpretation:
Maps and bathymetric charts should be consulted and specific topographic
features which may affect the dispersal of wastes (e.g. marine canyons) should
be identified.
The geochemical observations of sediments in and around the disposal site
should be related to the type of waste(s) involved. The range of chemical
constituents should be the same as that provided for the characterization of
the waste or other matter, with the minimum range of data set out in
paragraph Al above.
In areas where wastes may reach the bottom, sediment structure (i.e. the
distribution of gravel, sand, silt and clay) as well as benthic and epibenthic
community characteristics should be considered for the site area.
ANNEX 6 Page 12
Mobility of sediments due to waves, tides or other currents should be
considered in any waste disposal site assessments. The possibility of seismic
activities in the area under consideration should be investigated, in
particular when hazardous wastes in packaged form are concerned. The
distribution of sediment types in an area provides basic information as to
whether dumped solids with certain characteristics will accumulate at a site
or be dispersed.
Sorption/desorption processes under the range of dump site redox and pH
conditions, with particular reference to exchanges between dissolved and fine
particulate phases, are relevant to the evaluation of the accumulative
properties of the area for the components of the waste proposed for dumping
and for their potential release to overlying waters.
8 Existence and effects of other dumpings which have been made in the dumping area (e.g. heavy metal background reading and organic carbon content).
Interpretation:
The basic assessment to be carried out of a site, either a new or an
existing one, shall include the consideration of possible effects that might
arise by the increase of certain waste constituents or by interaction (e.g.
synergystic effects) with other substances introduced in the area, either by
other dumpings or by river input and discharges from coastal areas, by
exploitation areas, and maritime transport as well as through the atmosphere.
The existing stress on biological communities as a result of such activities
should be evaluated before any new or additional disposal operations are
established. The possible future uses of the sea area should be kept under
consideration.
Information from baseline and monitoring studies at already established
dumping sites will be important in this evaluation of any new dumping activity
at the same site or nearby.
ANNEX 6 Page 13
9 In issuing a permit for dumping, Contracting Parties should consider whether an adequate scientific basis exists for assessing the consequences of such dumping, as outlined in this Annex, taking into account seasonal variations.
___l-l
Interpretation:
When a given location is first under consideration as a candidate disposal
site, the existing data basis should be evaluated with a view to establishing
whether the main characteristics are known in sufficient detail or accurately
enough for reliable modelling of waste effects. Many parameters are so
variable in space and time that a comprehensive series of observation have to
be designed to quantify the key properties of an area over the various seasons.
If at any time, monitoring studies demonstrate that existing disposal
sites do not satisfy these criteria, alternative disposal sites or methods
should be considered.
c- GENERAL CONSIDERATIONS AND CONDlTIONS
1 Possible effects on amenities (e.g. presence of floating or stranded material, turbidity, objectionable odour, discolouration and foaming).
2 Possible effects on marine life, fish and shell fish culture, fish stocks and fisheries, seaweed harvesting and culture.
--
Interpretation:
Particular attention should be given to those waste constituents which
float on the surface or which, in reaction with sea water may lead to floating
substances and which, because they are confined to a two-dimensional rather
than a three-dimensional medium, disperse very slowly. The possibility of
reaccumulation of such substances caused by the presence of surface
ANNEX 6 Page 14
convergences which may lead to interferences with amenities as well as with
fisheries and shipping should be investigated.
Information on the nature and extent of commercial and recreational
fishery resources and activities should be gathered.
Body burdens of persistent toxic substances (and, in the case of
shellfish, pathogens) in selected marine life and, in particular, commercial
food species from the dumping area should be established.
Certain grounds although not in use for fishing may be important to fish
stocks as spawning, nursery or Seeding areas, and the effects of sea disposal
on these grounds should be considered.
The effects which waste disposal in certain areas could have on the
habitats of rare, vulnerable or endangered species should be recognized.
Besides toxicological and bioaccumulation effects of waste constituents
other potential impacts on marine life, such as nutrient enrichment, oxygen
depletion, turbidity, modification of the sediment composition and blanketing
of the sea floor, should be addressed.
It should also be taken into account that disposal at sea of certain
substances may disrupt the physiological processes used by fish for detection
and may mask natural characteristics of sea water or tributary streams, thus
confusing migratory species which consequently lose their direction, go
unspawned or fail to find food.
ANNEX 6 Page 15
3 Possible effects on other uses of the sea (e.g. impairment of water quality for industrial use, underwater corrosion of structures, interference with ship operations from floating materials, interference with fishing or navigation through deposit of waste or solid objects on the sea floor and protection of areas of special importance for scientific or conservation purposes).
Interpretation:
Consideration of possible effects on the uses of the sea as outlined in
paragraph C3 should include interferences with fishing, such as the damaging
or fouling of fishing gear. Any possibility of excluding the future uses of
the sea dumping area for other resources, such as water use for industrial
purposes, navigation, erection of structures, mining, etc., should be taken
fully into account.
Areas of special importance include those of interest for scientific
research or conservation areas and distinctive habitats of limited
distribution (such as seabird rookeries, kelp beds or coral reefs);
information should also be provided on all distinctive habitats in the
vicinity of the proposed site which might be affected by the material to be
dumped. Attention should also be given to geological and physiographical
formations of outstanding universal value from the point of view of science,
conservation or natural beauty.
ANNEX 6 Page 16
4 The practical. availability of alternative land-based methods of treatment, disposal or elimination, or of treatment to render the matter less harmful for dumping at sea.
I. Bumping of wastes and other matter at sea
Before considering the dumping of matter at sea every effort should be
made to determine the practical availability of alternative land-based methods
of treatment, disposal or elimination, or of treatment to render the matter
less harmful for dumping at sea.
The practical availability of other means of disposal should be
considered in the light of a comparative assessment of:
- Human health risks
- Environmental costs
- Hazards (including accidents) associated with treatment, packaging,
transport and disposal
- Economics (including energy costs)
- Exclusion of future uses of disposal areas,
for both sea disposal and the alternatives.
If the foregoing anal.ysis shows the ocean alternative to be less
preferable, a licence for sea disposal should not be given.
2 Incineration of wastes and other matter at sea
Recognizing the provisions of Regulation 2(2) of the Regulations for the
Control of Incineration of Wastes and Other Matter at Sea, the appropriate
ANNEX 6 Page 17
authorities should ensure that, before considering the incineration of wastes
at sea, every effort has been made to determine the practical availability of
alternative land-based methods of treatment, disposal or elimination of the
wastes concerned.
Accordingly, authorities should take appropriate steps to ensure that the
generators of those wastes that are proposed for incineration at sea have
applied the generally accepted hierarchy of waste management in their
assessment of alternative technologies.
The hierarchy is described as follows:
Existing and developing methods for managing hazardous wastes are
commonly organized into a hierarchy that accords preferred status to
methods that reduce risk by reducing the quantity and degree of hazard of
a waste.
The highest tier in the hierarchy includes those methods - collectively
referred to as reduction - that actually avoid the generation of waste.
Techniques that reuse or recover wastes after they are generated occupy
the next tier. Techniques that treat or destroy wastes are preferred
over those that merely contain or actually disperse wastes into the
environment.
Specific technological approaches which have been shown to achieve
significant reductions in the amounts of hazardous waste include process and
equipment changes, chemical substitution, product reformulation, as well as a
variety of maintenance, operational and housekeeping changes as well as waste
reuse.
It should, however, be recognized that some countries producing wastes
that need to be destroyed by incineration, either do not possess suitable
land-based incinerators or have limited capacity at such facilities.
Furthermore, export of wastes to land-based incinerators in other countries
ANNEX 6 Page 18
may be restricted by legal, economic or other factors including available
capacities and national priorities. These circumstances may, in certain
cases, constitute grounds for concluding that practical alternatives to
incineration at sea are not available. Nevertheless, permits for incineration
at sea should not be issued unless conformity with the Regulations for the
Control of Incineration of Wastes and Other Matter at Sea, and the Technical
Guidelines thereto, can be assured.
In applying the hierarchy of waste management, alternatives to
incineration of wastes at sea should also be considered in the light of
comparative assessment of:
Human health risks;
Environmental costs;
Hazards (including accidents) associated with treatment, packaging,
transport and disposal;
Economics (including energy costs);
Exclusion of future uses of incineration sites
for both incineration at sea and the alternatives.
If the foregoing analysis shows the ocean alternative to be less
preferable, a licence for incineration at sea should not be given.
Where it is determined that alternatives to incineration at sea are, in
practice, not available, emphasis should be placed on the introduction of
improved waste management procedures with particular attention being given to
the application of the hierarchy of waste management described above. If it
is predicted that, despite the application of waste management procedures,
arisings of wastes requiring incineration are likely to be maintained, or to
increase significantly, consideration should be given to establishing suitable
land-based alternatives, or increasing their capacity, to meet national
requirements.
***
-ANNEX 29
RESOLUTION J,DC .23( 10)
GUIDELINES FOR THE APPLICATION OF THE ANNEXES TO THE DISPOSAL OF DREDGED MATERIAL
(LDC 10115, annex 2)
THE TENTH CONSULTATIVE MEETING,
RECALLING Article I of the Convention on the Prevention of Marine
Pollution by Dumping of Wastes and Other Matter, 1972, which provides that
Contracting Parties shall individually and collectively promote the effective
control of all sources of pollution in the marine environment,
RECOGNIZING that the major part of the sediments dredged from the
waterways of the world either are either not polluted or may possess
mitigative properties that diminish the development of adverse environmental
impacts after disposal at sea,
RECOGNIZING FURTHER that the major cause of the contamination of
sediments requiring to be dredged is the emission of hazardous substances into
internal and coastal waters and that problems will continue until such
emissions are controlled at source,
RECOGNIZING ALSO the need for maintaining open shipping lanes and
harbours for maritime transport and that undue burden should be avoided with
regard to the interpretation and application of the provisions of the
Convention on the Prevention of Marine Pollution by Dumping of Wastes and
Other Matter, 1972 (London Dumping Convention, 1972),
RECALtING that the Eighth Consultative Meeting by resolution LDC.17(8)
adopted Guidelines for the Application of Annex III to the London Dumping
Convention with a view to providing guidance for the uniform interpretation of
the factors to be considered in establishing criteria governing the issue of
permits for disposal at sea,
RECOGNIZING that for the disposal of dredged material at sea not all of
the factors listed in Annex III and their corresponding interpretations are
applicable,
ANNEX 29 Page 2
RECALLIhJG FURTHER that the Pourth Consultative Meeting adopted Interim
Guidelines for the Implementation of paragraphs 8 and 9 of Annex I to the
Convention with a view to providing guidance for the interpretation of certain
conditions under which permits may be issued for disposal at sea of hazardous
substances for which sea disposal is otherwise prohibited,
NOTING the discussion which took place within the Scientific Group on
Dumping on the need to prepare specific guidelines for the application of the
Annexes to the Convention with regard to the disposal at sea of dredged
material,
HAVING CONSIDERED the draft Guidelines for the Application of the Annexes
to the Disposal of Dredged Material at Sea prepared by the Scientific Group on
Dumping)
I. ADOPTS the Guidelines for the Application of the Annexes to the Disposal
of Dredged Material at Sea as set out at Annex here to;
2. RESOLVES that Contracting Parties to the Convention when assessing the
suitability of dredged material for disposal at sea shall take full account of
the Guidelines for the Application of the Annexes to the Disposal of Dredged
Material at Sea;
3. AGREES to review the Guidelines for the Application of the Annexes to
the Disposal of Dredged Material at Sea within five years time in light of
experience gained by Contracting Parties with these guidelines, in particular
with regard to the application of the terms “trace contaminants**, **rapidly
rendered harmless” and **special care” as defined for disposal of dredged
material at sea;
4. REQUESTS Contracting Parties to submit to the Organization for
distribution to all Contracting Parties information on their experience
gained with the above guidelines, including case studies;
5. UPON Contracting Parties to take all practicable steps to reduce
pollution of marine sediments, including control of emissions of hazardous
substances into internal and coastal waters. 534Sw/jeh
ANNEX
ANNEX 29 Page 3
GIJIDELLNES FOR THE APPLICATION OF THE ANNEXES TO THE DISPOSAL OF DREDGED MATERIAL
1 INTRODUCTION
1.1 In accordance with article IV(l)(a) of the Convention, Contracting
Parties shall prohibit the dumping of dredged material containing substances
listed in Annex I unless the dredged material can be exempted under
paragraph 8 (rapidly rendered harmless) or paragraph 9 (trace contaminants) of
Annex I.
1.2 Furthermore, in accordance with article IV(l)(b) of the Convention,
Contracting Parties shall issue special permits for the dumping of dredged
material containing substances described in Annex IT and, in accordance with
Annex II, shall ensure that special care is taken in the disposal at sea of
such dredged material.
1.3 In the case of dredged material not subject to the provisions of
articles IV(l)(a) and IV(l)(b), contracting Parties are required under
article IV(l)(c) to issue a general permit prior to dumping.
1.4 Permits for the dumping of dredged material shall be issued in accordance
with article IV(2) which requires careful consideration of all the factors set
forth in Annex III. In this regard, the Eighth Consultative Meeting in
adopting Guidelines for the Implementation and Ilniform Interpretation of
Annex III (resolution LDC.17(8)) resolved that Contracting Parties shall take
full account of these Guidelines in considering the factors set forth in that
Annex prior to the issue of any permit for the dumping of waste and other
matter at sea.
1.5 With regard to the implementation of paragraphs 8 and 9 of Annex I to
the Convention, the Fourth Consultative Meeting adopted Interim Guidelines
(LDC IV/lZ, annex 5) which provide advice concerning the conditions under
which permits may be issued for dumping wastes containing Annex I substances,
and concerning the evaluation of the terms “trace contaminants” and “rapidly
rendered harmless”
1.6 Notwithstanding the gcncral guidance rcfcrrca to in paragrapns A.4
and 1.5 shove, suhsequent deliberations by Contracting Parties have determined
that the special characteristics of dredged material warrant separate
guidelines to be used when assessing the suitability of dredged material for
disposal. at sea. Such guidelines would he used by regulatory authorities in
the interpretation of paragraphs 8 and 9 of Annex I, and in the application of
the considerations under Annex III. These Guidelines for the Application of
the Annexes to the Disposal of Dredged Material have been prepared for this
purpose and, more specifically, are intended to serve the following functions:
.1 to replace the Interim Guidelines for the Implementation of
paragraphs 8 and 9 of Annex T as they apply to dredged material; and
.2 to replace section A of the Guidelines for the Implementation and
Uniform Interpretation of Annex TI.1 (resolution LDC.17(8)).
2 CONDITIONS IJNDER WHlCH PERHlTS FOR DIJMPING OF DREDGED MATERTAL BAY BE ISSlJED
2.1 A Contracting Party may after consideration of the factors contained in
Annex III issue a general permit for the dumping of dredged material if:
.1
7 . _
-_
although Annex I substances are present, they are either determined
to he present as a “trace contaminant” or to he “rapidly rendered
harmless” by physical, chemical or biological processes in the sea
provided they do not:
- make edible organisms unpalatahle, or
- endanger human health or that of domestic animals; and
the dredged material contains less than significant amounts* of
substances listed in part A of Annex II and meets the requirements
of part C of Annex II.
* The following interpretations of “significant amounts” were agreed by the Eighth Consultative Meeting:
Pesticides and their by-products not covered by Annex I and lead and lead compounds:
_O.OSX or more by weight in the waste or other matter
All other substances listed in Annex II, 0.1% or more by weight in paragraph A: the waste or other matter
ANNEX 29 Page 5
2.2 If the conditions under 2.1.2 above are not met a Contracting Party may
issue a special permit provided the condition under 2.1.1 has been met. Such
a special permit should either prescribe certain special care measures and/or
give limiting conditions prescribed by national authorities to diminish the
pollution source.
2.3 The assessment procedures and tests described in the following sections
are considered to apply equally to the interpretation of “harmlessness”
(paragraph 8 of Annex I) and “trace contaminants’* (paragraph 9 of Annex I)
when applied in association with sections B and C of the Annex III guidelines.
3 ASSESSMENT OF THE CHARACTERISTICS AND COMPOSITION OF DREDGED MATERIAL
This section replaces the Guidelines for the Implementation and Uniform
Interpretation of Annex III, part A, and provides an interpretation for the
assessment of dredged material. It should be considered in conjunction with
parts B and C of the Guidelines on Annex TII.
1 Total amount and average composition of matter dumped (e.g. per year)
2 Form, e.g. solid, sludge, liquid, or gaseous
For all dredged material to be disposed of at sea the following
information should be obtained:
gross wet tonnage per site (per unit time)
method of dredging
visual determination of sediment characteristics
(clay-silt/sand/gravel/boulder)
In the absence of appreciable pollution sources dredged material may
be exempted from the testing referred to in these Guidelines in the
ANNEX 29 @age! 6
following section if it meets one of the criteria listed below; in such
cases the provisions of Annex III sections B and C should be taken into
account:
.f Dredged material is composed predominantly of sand, gravel or
rock and the material is found in areas of high current or wave
energy such as streams with large bed loads or coastal areas
with shifting bars and channels;
.2 Dredged material is for beach nourishment or restoration and is
composed predominantly of sand, gravel, or shell with particle
sizes compatible with material on the receiving beaches; and
.3 In the absence of appreciable pollution sources, dredged
material not exceeding 10,000 tonnes per year from small,
isolated and single dredging operations, e.g. at marinas or
small fishing harbours, may be exempted. Larger quantities may
be exempted if the material proposed for disposal at sea is
situated away from known existing and historical sources of
pollution so as to provide reasonable assurance that such
material has not been contaminated.
3 Properties: physical (e.g. solubility and density), chemical and biochemical (e.g. oxygen demand, nutrients) and biological (e.g. presence of viruses, bacteria, yeasts, parasites)
For dredged material that does not meet the above exemptions, further
information will be needed to fully assess the impact. Sufficient
information may be available from existing sources, for example from
field observations on the impact of similar material at similar sites or
from previous test data on similar material tested not more than five
years previously.
ANNEX 29 Page 7
In the absence of this information, chemical characterization will be
necessary as a first step to estimate gross loadings of contaminants.
This should not mean that each dredged material should be subjected
to exhaustive chemical analysis to establish the concentrations of a
standard wide-ranging list of chemical elements or compounds; knowledge
of local discharges or other sources of pollution, supported by a
selective analysis, may often be used to assess the likelihood of
contamination. Where such an assessment cannot be made the levels of
Annex I and II substances must be established as a minimum.
Where this information coupled with knowledge of the receiving area,
indicates that the material to be dumped is substantially similar in
chemical and physical properties to the sediments at the proposed
disposal site, testing described in the following section might not be
necessary.
Where chemical analysis is appropriate, further information may also be
useful in interpreting the results of chemical testing, such as:
- density;
- per cent solids (moisture content);
- grain size analysis (% sand, silt, clay); and
- total organic carbon (TOC).
In addition, there are several other parameters which may facilitate the
interpretation of the behaviour, fate and effects of dredged material
(e.g. sediment transport, pollutant transformation, sediment mitigative
properties).
Sampling of sediments from the proposed dredging site should represent
the vertical and horizontal distribution and variability of the material
to be dredged. Samples should be spaced so as to identify and
differentiate between non-contaminated and contaminated locations.
ANNEX 29 Page 8
4 Toxicity
5 Persistence: physical, chemical and biological
6 Accumulation and biotransformation in biological materials or sediments
The purpose of testing under this section is to establish whether the
disposal at sea of dredged material containing Annex I and II substances
might cause undesirable effects, especially the possibility of chronic or
acute toxic effects on marine organisms or human health, whether or not
arising from their bioaccumulation in marine organisms and especially in
food species.
The following biological test procedures might not be necessary if the
previous characterization of the material and of the receiving area
allows an assessment of the environmental impact. If, however, the
previous analysis of the material shows the presence of Annex I or
Annex II substances in considerable quantities or of substances whose
biological effects are not understood, and if there is concern for
antagonistic or synergistic effects of more than one substance, or if
there is any doubt as to the exact composition or properties of the
material, it may be necessary to carry out suitable biological test
procedures. These procedures should be carried out on the solid phase
with bottom dwelling macrofauna and may include the following:
- acute toxicity tests;
- chronic toxicity tests capable of evaluating long-term sub--lethal
effects, such as bioassays covering an entire life cycle; and
- tests to determine the potential for bioaccumulation of the
substance of concern.
ANNEX 29 Page 9
Substances in dredged material, when entering the marine environment
may undergo physical and chemical alteration that directly affects the
release, retention, transformation and/or toxicity of these substances.
This shall be taken into particular account when carrying out the various
tests mentioned above and when interpreting the results of these tests
for actual or future dumping site conditions.
7 Susceptability to physical, chemical and biochemical changes and interaction in the aquatic environment with other dissolved organic and inorganic materials
-
Contaminants in dredged material, after dumping, may be altered by
physical, chemical and biochemical processes to more or to less harmful
substances. The susceptability of dredged material to such changes
should be considered in the light of the eventual fate and effects of the
dredged material. In this context field verification of predicted
effects is of considerible importance.
8 Probability of production of taints or other changes reducing marketability of resources (fish, shellfish, etc.)
Proper dump site selection rather than a testing application is
recommended. Site selection to minimize impact on commercial or
recreational fishery areas is a major consideration in resource
protection and is covered in greater detail in section C2 of Annex III.
ANNEX 29 Page 10
4 DISPOSAL MANAGEMENT TECHNIQUES
4.1 Ultimately, the problems of contaminated dredged material disposal can be
controlled effectively only by control of point source discharges to waters
from which dredged material is taken. Until this objective is met, the
problems of contaminated dredged material may be addressed by using disposal
management techniques.
4.2 The term *‘disposal management techniques*’ refers to actions and processes
through which the impact of Annex I or Annex II substances contained in
dredged material may be reduced to, or controlled at, a level which does not
constitute a hazard to human health, harm to living resources, damage to
amenities or interference with legitimate uses of the sea. In this context
they may, in certain circumstances, constitute additional methods by which
dredged material containing Annex I substances may be “rapidly rendered
harmless*’ and which may constitute “special care” in the disposal of dredged
material containing Annex II substances.
4.3 Relevant techniques include the utilization of natural physical, chemical
and biological processes as they affect dredged material in the sea; for
organic material these may include physical, chemical or biochemical
degradation and/or transformation that result in the material becoming
non-persistent, non-toxic and/or non--biologically available. Beyond the
considerations of Annex III sections B and C, disposal management techniques
may include burial on or in the sea floor followed by clean sediment capping,
utilization of geochemical interactions and transformations of substances in
dredged material when combined with sea water or bottom sediment, selection of
special sites such as in abiotic zones, or methods of containing dredged
material in a stable manner (including on artificial islands).
4.4 Iltilization of such techniques must be carried out in full conformity
with other Annex III considerations such as comparative assessment of
alternative disposal options and these guidelines should always be associated
with post-disposal monitoring to assess the effectiveness of the technique and
the need for any follow-up management action.
***
1 EUNWAD L TOBAGO, ANTIGUA BARPVDA. PAIISADOS, DOMINKA, GIWNADA. GUYANA, ,ann*xx,MoNTsBmr, ST WTTS C NEWIS, ST LUCIA, ST VlNCBNT L GRmADINES systanmm wdles Unit IPW#ItS~
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Batstone, Smith, and Wilson, The Safe Disposal of Hazardous Wastes: The Special Needs and Problems of Developing Countries Le Moigne, Barghouti, and PIusqueIlec, Technological and Institutional Innovation in Irrigation Swanson and Wolde-Semait, Africa‘s Public Enterprise Sector and Evidence of Reforms
Razavi, The New Era of Petroleum Trading: Spot Oil, Spot-Related Contracts, and Futures Markets Asia Technical Department and Europe, Middle East, and North Africa Technical Department, Improving the Supply of Fertilizers to Developing Countries: A Summa y of the World Bank’s Experience Moreno and Fallen Bailey, Alternative Transport Fuels from Natural Gas International Commission on Irrigation and Drainage, Planning the Management, Operation, and Maintenance of Irrigation and Drainage Systems: A Guide for the Preparation of Strategies and Manuals (also in French, 99F)
Veldkamp, Recommended Practices for Testing Water-Pumping Windmills van Meel and Smulders, Wind Pumping: A Handbook Berg and Brems, A Case for Promoting Breastfeeding in Projects to Limit Fertility Banerjee, Shrubs in Tropical Forest Ecosystems: Examples from India Schware, The World Software Industry and Software Engineering: Opportunities and Constraints for Newly Industrialized Economies Pasha and McGarry, Rural Water Supply and Sanitation in Pakistan: Lessons from Experience Pinto and Besant-Jones, Demand and Netback Values for Gas in Electricity Electric Power Research Institute and EMENA, The Current State of Atmospheric Fluidized-Bed Combustion Technology Falloux, Land lnformation and Remote Sensing for Renewable Resource Management in Sub-Saharan Africa: A Demand-Driven Approach (also in French, 108F)
Carr, Technology for Small-Scale Farmers in Sub-Saharan Africa: Experience with Food Crop Production in Five Major Ecological Zones Dixon, Talbot, and Le Moigne, Dams and the Environment: Considerations in World Bank Projects Jeffcoate and Pond, Large Water Meters: Guidelines for Selection, Testing, and Maintenance Cook and Grut, Agroforesty in Sub-Saharan Africa: A Farmer‘s Perspective Vergara and Babelon, The Petrochemical Industry in Developing Asia: A Review of the Current Situation and Prospects for Development in the 1990s McGuire and Popkins, Helping Women Improve Nutrition in the Developing World: Beating the Zero Sum Game Le Moigne, Plusquellec, and Barghouti, Dam Safety and the Environment Nelson, Dryland Management: The “Desertification” Problem Barghouti, Timmer, and Siegel, Rural Diversification: Lessons from East Asia Pritchard, Lending by the World Bank for Agricultural Research: A Review of the Years 1981 through 1987 Asia Region Technical Department, Flood Control in Bangladesh: A Plan for Action Plusquellec, The Gezira Irrigation Scheme in Sudan: Objectives, Design, and Performance Listorti, Environmental Health Components for Water Supply, Sanitation, and Urban Projects Dessing, Support for Microenterprises: Lessons for Sub-Saharan Africa Barghouti and Le Moigne, Irrigation in Sub-Saharan Africa: The Development of Public and Private systems Zymelman, Science, Education, and Development in Sub-Saharan Africa van de Walle and Foster, Fertility Decline in Africa: Assessment and Prospects
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