20 



observations. In other words, it 

 should be possible to describe 

 system conditions that are no more 

 than a few days to two months old. 



(g) An EMP must be adaptive. 

 Elements should be deleted if 

 additional work on these elements 

 seems unlikely to produce 

 additional valuable information. 

 Other elements may be added if an 

 effective argument can be made for 

 the addition. Funds always will be 

 limiting, therefore the addition of 

 new elements most likely will be 

 contingent upon the deletion of 

 others. 



3 J Building A Logical Structure 



The next step entailed the 

 construction of a framework or 

 structure for identifying, examining, 

 and displaying probable relationships. 

 Without a structure, one could respond 

 to endless claims about project impacts 

 without a logical and graphical basis 

 for considering the reasonableness of 

 those claims. Three basic questions 

 were asked initially: 



(a) What specific activities (dredging 

 techniques, disposal operational 

 control, etc.) are associated with 

 dredged material management 

 operations within the DAMOS 

 Program? 



(b) What physical and chemical 

 environmental alterations are 

 associated with those activities? 



(c) What biological responses are 

 associated with those physical or 

 chemical environmental 



alterations? 



Information about project activities 

 (such as dredging techniques, volumes, 

 etc.) is usually "given". Primary 

 environmental alterations and direct 

 biological impacts resulting from 

 dredging and dredged material 

 disposal operations can be described 

 adequately from previous research and 

 dredging operations experience. 

 Secondary environmental alterations, 

 particularly longer-term changes 

 affected by the altered disposal site 

 conditions, are not known 

 quantitatively and cannot be predicted 

 accurately without considerable effort. 



The concerns about impacts of 

 dredged material disposal operations 

 on the ecological resources of the 

 project area were approached by 

 devising a plan for linking secondary 

 environmental alterations to probable 

 changes in the structure and function 

 of biological constituents. The three 

 TAG meetings were directed to define 

 which relationships ultimately would 

 structure the monitoring plan. Initial 

 efforts were focussed at identifying 

 specific information resources and 

 needs; these included physical 

 processes, ecological structure and 

 function, and the hypothesized 

 physical-chemical-biological linkages 

 which existed. 



The physical processes identified 

 were the behaviors of new dredged 

 material during its descent to the 

 bottom and following its deposition on 

 the bottom. Decisions about 

 non-physical elements proposed for 

 incorporation into the EMP would be 

 facilitated by the existing 



An Integrated, Tiered Approach to Monitoring and Management of Dredged Material Disposal Sites 



