Appendix F: Hypothetical Example

Appendix F

Hypothetical Example

Appendix F provides the examples used in the text in a continuous format.

This is meant for illustrative purposes only and is provided here for the reader's

convenience.

Description of the Dredged Material Management

Activity

A local marina has proposed dredging 10 new slips. The existing water

depths at the slips is 1.5 m (5 ft) mean lower low water (MLLW). Each slip will

be 15 6 m (50 20 ft) and dredged to a depth of 3 m (10 ft) MLLW with a

0.6-m (2-ft) over-dredge allowance. The project will also require dredging of the

channel resulting in an estimated 76,500 cu m (100,000 cu yd) of dredged

material. A clamshell dredge will remove the material to a hopper barge for

transport to an offshore unconfined management area for which a site designation

report is available. The water depth near the site averages 30 m (100 ft), and

there is low to moderate wave energy.

Description of the Habitat Surrounding the

Management Site

The risk assessor used the following questions to guide the description of the

habitat at and near the management area (disposal site) where the dredged

material from the marina and channel will be transported.

a. What is the size of the management area (disposal site)?

b. What is the size of the local water body?

c. Are there fishery breeding, nursery, or feeding areas near the site?

d. Is the site near or adjacent to seasonal migration pathways for fish,

mammals, or piscivorous birds?

e. Are there biological reefs near the site (shellfish reefs, coral reefs) or

other particularly productive benthic environments?

Appendix F Hypothetical Example