Selecting Assessment End Points

community structure of the fish populations near a dredged material management

site.

The selection of assessment and measurement end points should be an inclusive

process which includes input from those groups which may be affected by dredged

material management decisions. The process of selecting assessment end points

began with the conceptual model when habitats and other receptors at or near the

site were identified. The problem formulation continues to refine and explicitly state

the assessment end points. They can be specific to the receptors that are present at

and adjacent to the site.

The number of assessment endpoints selected at a site will vary depending on

site characteristics, the habitats and receptors, and concerns of site managers and

other interested parties. Additional guidance on the selection of assessment

endpoints is available in USEPA/ERT (1997) and in guidance developed by various

USEPA regions and states including California, Massachusetts, and Texas.

Selecting Assessment End Points

This subsection identifies the criteria used to select and evaluate, in narrative

form, assessment end points. Figure 6 summarizes the selection criteria. USEPA

Guidance (USEPA 1992a and references cited therein) suggests six criteria for such

evaluations.

a. Ecological relevance.

b. economic importance.

c. Measurable

d. Susceptible and sensitive to chemically induced stress or other stresses.

e. Unambiguously defined.

f. Logically and practically related to the management decision.

The risk assessment should include a narrative evaluation of whether and how each

of these criteria are met.

Chapter 2 Problem Formulation