Sediment Quality Guidelines

Question 1

What is sediment?

Answer 1

Particles derived from rocks or biological materials that are stationary in the bottom of a water course

Question 2

What are the four reasons why sediment is important?

Answer 2

1. habitat
2. nutrient cycling (C, N and P)
3. accumulation of contaminants
4. become source of contaminant for organism

Question 3

What are sediment guidelines

Answer 3

numerical concentrations or narrative statements intended to protect all forms of aquatic life and all aspects of aquatic life cycles during indefinite exposure to substances associated with bed sediments.

Question 4

How should sediment quality guidelines be developed?

Answer 4

concentration-response data that describe acute and chronic toxicity to individuals to sensitive life stages for sensitive organisms

Question 5

What are the recommend use of sediment guidelines?

Answer 5

Canadian Interim Sediment Quality Guidelines and Probable Effect Levels can be used to evaluate the degree to which adverse biological effects are likely to occur due to exposure to a substance in sediment

Question 6

What are the common use of the sediment guidelines?

Answer 6

provide protective concentrations below which toxic effects are unlikely and identify sites for further assessment

Question 7

What do ISQGs and PELs refer to?

Answer 7

total concentrations of an element/trace metal in surficial sediments as quantified with a strong acid followed with an analysis by standard analytical protocol

Question 8

What are the potential applications of SQGs?

Answer 8

1. National benchmarks to assess whether existing or predicted sediment quality conditions pose a threat to benthic organisms
2. defining site specific objectives to maintain and protect sediment quality conditions
3. defining site specific remediation objectives to improve sediment quality conditions

Question 9

What is a limitation to sediment quality guidelines?

Answer 9

metals content in sediments varies naturally-metal content in sediment is a natural function of particle size distribution