Classification 
The purpose of the classification research is to develop an effective scheme for defining those 
waters for which similar ambient levels of suspended or bedded sediments are expected. We 
anticipated the final solution will incorporate information about water body type, geographic 
setting, and specific, local hydrologic settings. This proposed classification scheme that results 
should be review with or compared to the classification in use (at that time) for establishing 
reference conditions for biological criteria. 
Gap Analysis 
Research into the problems associated with suspended and bedded sediments also is being 
carried out by other groups. The Army Corps of Engineers is working on the effects of 
resuspension associated with dredging projects, for example (Wilber and Clarke 2001). Goal 8 
research (Kaufmann et al. 1999, Kaufmann and Robison 1998, EPA 2000), research supported by 
the Office of Wetlands, Oceans, and Watersheds (OWOW) (TMDL framework for clean 
sediments), and NERL are currently contributing to the development of loading estimates and 
models (Figure 7, box 8). However, the work has barely begun on the effects of sediments to 
aquatic systems, at the low levels that may exert long-term, chronic effects. The first step 
outlined in the critical path is the review of the state of science. The intent of this gap section is 
to describe what work would remain to reach the goals once NHEERL completed the work 
outlined. The dilemma is that NHEERL will not be in a position to outline the details of what we 
will do until we complete the state of science review. At that point and in concert with Division 
management decisions on FTE dedicated to this project, the gaps that will remain can be 
identified. 
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