3.3 Compilation of Information (Cont.)

is because Tier I is likely to resolve at least some issues, and Tier I provides much

of the information that will guide evaluation in higher tiers if that should be

necessary, including identification of the COC for the dredged material, CDF, and

pathway being evaluated.

Information on a variety of physical, chemical, and biological factors related

to the dredging site, the dredged material, and the CDF is important to maximize

the utility of Tier I. Information on these factors may exist in a wide variety of

sources, and the useful sources may differ for each dredging project. Therefore,

the following lists are intended merely to indicate possible sources and stimulate

thinking about sources of relevant existing information. Not all potential sources

will provide relevant information for every pathway, and sources not listed will be

helpful on others. It is not possible to determine in advance which sources will

provide information useful in Tier I. All involved parties should work

cooperatively to identify and obtain relevant existing information for use in Tier I.

Considerations relevant to the potential for the dredged material to be

contaminated include:

Sources of COC

Pathways of COC transport to the dredging site

Naturally occurring substances that may be harmful to biota

Urban and agricultural runoff

Sewer overflows/bypassing

Industrial and municipal wastewater discharges

Previous dredged or fill discharges

Landfill leachate/groundwater discharge

Spills of oil or chemicals

Releases from Superfund and other hazardous waste sites

Illegal discharges

Air deposition

Biological production (detritus)

Mineral deposits

The information gathering must be as complete as is reasonably possible,

including existing information from all reasonably available sources. This will

increase the utility of the Tier I evaluation and the likelihood that decisions

3-6

Chapter 3

Initial Evaluations