Disposal at sea permit application guide: disposal site selection, appendix C.2

Step 2: Characterization of candidate disposal sites^Footnote8

Water column characteristics

• Temperature, salinity, depth
• Dissolved oxygen
• Turbidity
• Currents and upwelling
• Bathymetry

Sediment characteristics

• Grain (particle) size
• Total organic carbon
• Contaminants^Footnote 9 (Appendix C.4 has the Minimum Sample Analytical Requirements table)
• CEPA regulated requirements: mercury (Hg), cadmium (Cd), PCBs & PAHs
• Other potential contaminants (site specific):
  • lead (Pb), copper (Cu), and other heavy metals
  • high molecular weight hydrocarbons, for example, petroleum hydrocarbons
  • PBDEs, dioxins and furans
  • chlorinated pesticides
  • nutrients (the requirement will vary according to site and Disposal at Sea Program instructions)

Biota characteristics

Requirements will vary according to site and Disposal at Sea Program instructions, but may include:

• identification of species and abundance of:
  • macroinfauna
  • meiofauna
  • macroepifauna
• macroepifauna; bioaccumulation (tissues): 2 species for Hg, Cd, Pb, Cu, PCBs, other heavy metals, petroleum hydrocarbons, pesticides

Step 3: Assessment of potential impacts at candidate sites

Direct physical impacts from disposal activity may include:

• reduction of light penetration, leading to sub-lethal effects or death of light sensitive organisms and habitats
• changes to benthic community structures and habitats
• reduced vitality or death of sessile benthic fauna through clogging of feeding mechanisms or smothering (especially filter-feeding organisms and sensitive habitats)
• alteration of current velocities and wave conditions affecting sediment regimes and leading to erosion of areas (such as seagrass beds)
• reduction in dissolved oxygen levels due to an increase in nutrient concentrations potentially resulting in anoxia and hypoxia

Potential biological impacts from disposal activity may include:

• disruption of the lifecycle (breeding, feeding, migration, resting) of a species
• adversely affecting the spatial distribution of a species
• fragmentation of an important population
• introduction of invasive species or disease that may impact the population, and
• practices that interfere with the recovery of a species

Examples of impact hypotheses

• During initial deposition, the material will not be carried through the water column to any sensitive area in amounts that would be harmful to the value or amenity of such areas
• The deposited material will not subsequently reach any sensitive areas (through resuspension and sediment transport) in amounts that would be harmful to the value or amenity of such areas
• Disposal of material will not result in transport of contaminated material to any sensitive area, contaminant increases in the sediments of such areas, contaminant uptake by biota in such areas or ensuing effects on such biota
• The deposited material will not subsequently reach any sensitive area (through erosion, re-suspension and sediment transport) in amounts that would cause unacceptable shoaling in shipping lanes or affect other human uses

Step 4: Comparison of candidate sites

Questions to consider include:

1. Do other government departments or agencies (for example, Parks Canada, Indigenous and Northern Affairs Canada, Fisheries and Oceans Canada, Natural Resources Canada or Transport Canada) have concerns or regulatory requirements pertaining to selection of this particular site?
2. Unusual topography or unique bottom features: Would disposal of material in this candidate site affect physical bottom feature that is unique within the local or regional area?
3. Physical sediment compatibility: Does the candidate site have similar sediment characteristics to anticipated waste material?
4. Chemical sediment compatibility: Does the candidate site have similar chemical characteristics to anticipated waste material?
5. Influence of past disposal: Would disposal of material in this candidate site be affected by previous disposal of waste material?
6. Living resources of limited distribution: Would disposal of material in this candidate site affect any living resources that do not have a coast-wide distribution?
7. Commercial fisheries: Would disposal of material in this candidate site affect any commercial fishing activity?
8. Recreational fisheries: Would disposal of material in this candidate site affect any recreational fishing activity?
9. Breeding and spawning areas: Would disposal of material in this candidate site affect breeding and spawning areas of any species?
10. Nursery areas: Would disposal of material in this candidate site affect nursery areas of any species?
11. Feeding areas: Would disposal of material in this candidate site affect feeding areas of any species?
12. Migration routes: Would disposal of material in this candidate site affect migration routes of species?
13. Critical habitat of threatened or endangered species: Would disposal of material in this candidate site affect critical habitat of threatened or endangered species?
14. Spatial distribution of benthos: Would disposal of material in this candidate site change the benthic invertebrate community structure (for example, fine-gain species to coarse-grain species, etc)?
15. Marine mammals: Would disposal of material in this candidate site affect marine mammals or their habitat (for example, gray whale feeding areas etc)?
16. Human health: Would disposal of material in this candidate site pose unacceptable risks to human health?^Footnote10
17. Mineral deposits: Would any known mineral deposits be affected by the disposal of material?
18. Navigation hazard: Would the disposal of material create a navigation hazard?
19. Other uses of the sea: Would disposal of material impact other uses of the sea not addressed elsewhere, such as cables, pipelines, tow boat lanes, and pilot transfer points?
20. Degraded areas: Would disposal in this candidate site continue to affect or improve the degraded area?
21. Recreational uses: Would disposal of material affect recreational uses?
22. Cultural or historic sites: Would disposal of material in this candidate site impact or protect a cultural and/or historic site?
23. Physical oceanography, waves and circulation: Would disposal of material affect wave or circulation patterns?
24. Direction of transport and potential for settlement: Would disposal of material affect the direction of sediment transport and potential for settlement?
25. Monitoring: Would use of this candidate site affect either on-going monitoring or the ability to monitor using conventional methods?
    • monitoring typically would include periodic hydrographic surveys and could include sediment sampling or biological data collection.
26. Shape and size of candidate site:
    
    • Is the candidate site suitable for the operation of the equipment?
    • Maneuverability of the equipment?
    • Is it orientated so the equipment can place material while heading into the waves?
    • Is the depth of water sufficient to open the hopper doors/dump scow?
    • Can the equipment operate safely?
27. Is the size of the candidate site large enough for long-term use?
28. Size of buffer zone: Is the candidate site a sufficient distance from important resources or features to protect them from any effect of disposal?
29. Potential for cumulative effects: Would disposal of material contribute to cumulative effects from other activities?

Step 5: Preparation of site monitoring and management plan

Management measures may include:

• directed disposal within the disposal site
  • to avoid or reduce impacts on sensitive benthic communities, which depends upon the equipment used and the ability to control disposal in the disposal site
• altering the time of year of operations to avoid critical life-cycle phases of sensitive marine organisms
• loading and disposal management
  • to reduce dispersal of turbid plumes in sensitive environments, which depends upon the availability of suitable equipment
• thin layer disposal to improve recolonization by benthic organisms

Site monitoring and management plans should include:

• management objectives relating to possible adverse effects that could develop at the disposal site
• consideration of the times, rates, quantities, and types of material disposed
• consideration of the various methodologies of monitoring the movement and characteristics of disposed  material
• impact hypotheses and a tiered approach for monitoring disposal operations
• effective monitoring programs for the material disposed
• target thresholds and associated response measures that may be applied should the project implementation monitoring indicate outcomes significantly different than expected