where multiple attributes with widely different value bases are involved (Keeney 

 and Raiffa 1976). 



Guided by the identification of management alternatives and resource 

 values, one can formulate the general assessment steps required to achieve the 

 prediction of probable outcomes (fig. 1, step 3). These steps are outlined 

 below in the (approximate) sequence that they must be performed for each 

 identified management alternative: 



1. Characterize source compositions and magnitudes for key contaminants. 

 The source characteristics (contaminant composition, concentration, 

 location, flux, etc.) represent a series of decision variables for 

 each source, i.e., factors which generally can be controlled through 

 the decision itself. 



2. Predict distributions of key contaminants in and on the water column 

 and in sediments as a function of source characteristics and time. 



a. Predict transport 



b. Predict transformations 



3. Predict rates and extents of habitat disruption and modification 

 for key organisms as a function of source characteristics and time. 



4. Predict bioaccumulation rate and levels for key contaminants in key 

 organisms as a function of exposure regime. 



5. Predict changes in population size and production of key species based 

 on bioaccumulation of contaminants and habitat disruption and 

 modification. 



6. Predict the outcomes, in terms of human health measures, as a function 

 of contaminant (and pathogen) concentrations in key organisms and the 

 general distribution of contaminants. 



7. Predict the outcomes, in terms of measures of recreational values , 



as a function of distribution of contaminants, habitat disruption and 

 modification, and population size/production of key species. 



8. Predict the outcomes, in terms of Ecological or Wilderness values and 

 Global Human Habitat values , as a function of habitat disruption and 

 modification and population size/production of key species. 



9. Design and implement research or monitoring strategies specifically 

 related to testing and validating the predictions in 2-8. 



It is obvious that few of the nine objectives outlined above represent 

 simple, currently available scientific technology. Each of the predictive 

 capabilities called for in objectives 2-8 requires sophisticated modeling 

 approaches that clearly involve many additional variables left implicit in the 

 outline. The prediction of outcomes is depicted In figure 2 to illustrate some 

 of these other information needs and the relationships to quantifying changes 

 in values. Whereas steps 1 and 9 above may be unique and under the control of 



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