London Convention Guidelines for Assessment of Dredged Material PIANC-Dredged Material

1. London Convention Guidelines for Assessment of Dredged Material PIANC-Dredged Material Management Guidance Documents Robert.m.engler@erdc.usace.army.mil

2. Dredging is essential to maintain navigation in ports, harbours, marinas and inland waterways; for the development of port facilities; for flooding mitigation; and for removal of sediments from structures, basins and water intakes. Dredged material worldwide is, by nature, similar to undisturbed sediments in inland and coastal waters. A smaller proportion of dredged material, however, is contaminated by human activity. Specific Guidelines for Assessment of Dredged Material Introduction

3. CAPITAL DREDGING - for navigation, to enlarge or deepen existing channel and port areas or to create new ones MAINTENANCE DREDGING - to ensure that channels, berths or construction works, etc., are maintained at their designed dimensions; and CLEAN UP DREDGING - deliberate removal of contaminated material for human health and environmental protection purposes. Evaluation of Need for Dredging and Disposal

4. The schematic provides a clear indication of the stages in the application of this guidance where important decisions should be made. Components are: 1. Dredged material characterization 2. Waste prevention audit and evaluation of disposal options 3. Is material acceptable 4. Identify and characterize dump-site 5. Determine potential impacts and prepare impact hypothesis(es) 6. Issue permit 7. Implement project and monitor compliance 8. Field monitoring and assessment (monitoring)

5. SOURCE CONTROL OTHER NO YES CAN MATERIAL BE MADE ACCEPTABLE? NO NO Representation of the Jurisdictional Boundary of the Convention Dredged Material Assessment Framework NO YES YES IMPLEMENT PROJECT & MONITOR COMPLIANCE NEED FOR DREDGING DREDGED MATERIAL CHARACTERIZATION IS MATERIAL ACCEPTABLE? DETERMINE POTENTIAL IMPACTS AND PREPARE IMPACT HYPOTHES(I/E)S IDENTIFY AND CHARACTERIZE DISPOSAL SITE ISSUE PERMIT? FIELD MONITORING & ASSESSMENT BENEFICIAL USE POSSIBLE? YES BENEFICIAL USE

6. NEED FOR DREDGING DREDGED MATERIAL CHARACTERIZATION SOURCE CONTROL

7. CAN MATERIAL BE MADE ACCEPTABLE? IS MATERIAL ACCEPTABLE? NO NO OTHER YES YES YES BENEFICIAL USE POSSIBLE? BENEFICIAL USE NO

8. NO IDENTIFY AND CHARACTERIZE DISPOSAL SITE DETERMINE POTENTIAL IMPACTS AND PREPARE IMPACT HYPOTHES(UE)S

9. ISSUE PERMIT? NO YES

10. YES IMPLEMENT PROJECT & MONITOR COMPLIANCE FIELD MONITORING & ASSESSMENT

11. Waste Prevention Audit For dredged material, the goal of waste management should be to identify and control the sources of contamination. SOURCE CONTROL STRATEGY 1. The continuing need for dredging; 2. The hazards posed by contaminants and the relative contributions of the individual sources to these hazards; 3. Existing source control programmes and other regulations or legal requirements; 4. Technical and economic feasibility; 5. The evaluation of the effectiveness of measures taken; and 6. Consequences of not implementing contaminant reduction.

12. Management Options • Reduce or control impacts to a level that will not constitute unacceptable risks • Treatment • Disposal management techniques • Methods of containing dredged material in a stable manner • The practical availability of other means of disposal should be considered in the light of a comparative risk assessment involving both dumping and the alternatives

13. Dredged Material Characterization Physical characterization • The basic physical characteristics required are the amount of material Exemptions from detailed characterization • Dredged material is excavated from a site away from existing and historical sources of appreciable pollution, so as to provide reasonable assurance that the • dredged material has not been contaminated, or • dredged material is composed predominantly of sand, gravel and/or rock, or • dredged material is composed of previously undisturbed geological materials.

14. Chemical Characterization • Available information • Geochemical characteristic • Contaminant routes /sources

15. Biological Characterization Biological tests should incorporate: • Acute toxicity • Chronic toxicity and sub-lethal effects • The potential for bioaccumulation • The potential for tainting at and in the vicinity of the disposal site.

16. Action List • Chemical and/or biological screening resulting in: - Wastes containing specified substances, or causing biological responses, exceeding the relevant upper level shall not be dumped, unless made acceptable. - Wastes which contain specified substances, or which cause biological responses, below the relevant lower levels should be considered to be of little environmental concern. - Wastes, which contain specified substances, or which cause biological responses, below the upper level but above the lower level require more detailed assessment before their suitability for dumping can be determined.

17. Dump-Site Selection Site Selection Considerations: • Physical, chemical and biological characteristics of the water-column and the seabed • Location of amenities, values and other uses of the sea in the area under consideration • Assessment of the constituent fluxes associated with dumping in relation to existing fluxes of substances in the marine environment • Economic and operational feasibility

18. Important Amenities, Biological Features and Uses of the Sea • The shoreline and bathing beaches • Areas of beauty or significant cultural or historical importance • Areas of special scientific or biological importance, such as sanctuaries • Fishing areas • Spawning, nursery and recruitment areas • Migration routes • Seasonal and critical habitats • Shipping lanes • Military exclusion zones • Engineering uses of the seafloor

19. Site Selection Consideration • Size of the dump-site • Site capacity • Evaluation of potential impacts • Contaminant mobility

20. Assessment of Potential Effects • Impact hypothesis • Integrate waste characteristics / site information • Comprehensive assessment • Emphasis on biological effects / habitat modification • Cumulative impacts

21. Monitoring Compliance monitoring, Field monitoring • Modify or terminate the field-monitoring programme • Modify or revoke the permit • Redefine or close the dump-site • Modify the assessment basis

22. Permit and Permit Conditions • The types, amounts and sources of materials to be dumped • The location of the dump-site(s) • The method of dumping • Monitoring and reporting requirements

23. International Navigation Association PIANC Dredged Material Management Guide (Supplement to Bulletin no. 96, 1987 • Assessment framework (LC) • Material characterization • Sustainable relocation

24. Management options • Contamination source control • Management strategy • Relevant background literature

25. Disposal • Aquatic (LC guides) • Land-based confined disposal - Contaminant release mechanisms - Processes - Pathways - Isolation - Surplus water treatment

26. Confined Disposal Site Management • Implementation guidelines • Monitoring (physical and environmental) • Evaluation • Optimization

27. Treatment • Pretreatment • Biological • Chemical • Thermal • Immobilization

28. Impact Assessment • Beneficial or adverse • Long- or short-term • Direct or indirect • Reversible or irreversible • Local or strategic • Independent or cumulative

29. Monitoring • Specification of baseline conditions • Port operational monitoring

30. International Navigation Association PIANC Management of Aquatic Disposal of Dredged Material (Working Group 1 - 1998)

31. Outline 1. Introduction 2. Management framework 3. Dredged material and site characterization • Survey and sampling methods • Dredged material characterization - Physical - Chemical - Ecotoxicological - Biological

32. Outline (cont.) • Characterization of disposal site - Physical - Chemical - Biological - Functional uses of receiving area

33. Outline (cont.) • Effects of disposal - Physical processes - Physical effects on ecology - Chemical and ecotoxicological - Functional uses / amenities

34. Outline (cont.) • International, regional and National environmental controls - General approaches - Marine and estuarine disposal - Inland waterways disposal

35. Planning and engineering for aquatic disposal - Regulatory decision framework - Technical decision framework - Project decision framework

36. Operational aspects of aquatic disposal - Operations plan - Monitoring requirements

37. References • Annexes - Description of physical properties of dredged material - Metals in sediments - List of international agreements, protocols and guidelines - Beneficial uses of dredged material in the aquatic environment - Mitigation measures - Consideration in design of monitoring plans

38. Managing Contaminated Dredged Material • Defining CDM • Risks • Chemical characteristics and sources

39. Identifying, Assessing, and Selecting Options • Planning CDM projects • State-of-the-art technologies • PIANC technical position • Documenting results with case studies

40. Dredging: The Environmental Facts Where to Find What You Need to Know • Dredging a vital process • Dredging for sustainable development • Dredging must be safe and sound

41. Sources of Information • CEDA • IADC • WODA • PIANC • IAPH • WEDA • EDA

42. CEDA • IAPH • WEDA • EDA