Initial Evaluations

Initial Evaluations

This chapter describes the activities conducted at the beginning of a CDF

pathway evaluation under Tier I. These initial Tier I evaluations include a

scoping process and an evaluation of existing information to determine the need

for pathway evaluations, identify relevant pathways for the project, and identify

COCs. The existing information for each relevant pathway is evaluated to

determine if a decision on the need for management actions can be made and

identify which pathways require more detailed evaluations in higher tiers.

3.1 Determination of the Need for Contaminant

Evaluations

The first step in the scoping process is the determination of the need for

contaminant evaluations based on the potential for presence of COC in the

dredged material. No further evaluation is needed if any one of the following

criteria is met:

The dredged material is excavated from a site far removed from existing

and historical sources of contaminants, so as to provide reasonable

assurance that the dredged material does not contain them.

The dredged material is composed predominantly of sand, gravel, and/or

rock.

The dredged material is composed of previously undisturbed geological

materials which have not been exposed to modern sources of pollution.

(However, note that potential impacts from natural mineral deposits must

also be considered).

Considering the dredged material characteristics in light of the above criteria,

determine whether there is reason to believe COC in the dredged material may be

of concern outside the CDF. The purpose at this initial stage is to eliminate

projects for which COC clearly do not warrant further evaluation. Unless this is

clear, the evaluation should be carried forward.

The decision, the rationale for which should be documented, will be either:

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Chapter 3

Initial Evaluations