60 



g 



"■§ 



i_ 

 +■" 

 c 

 0) 



o 



c 

 o 

 O 



+-> 

 c 



0) 



E 

 'u 



CD 

 CO 

 0) 



o 



t 



CO 



"Average 

 Mound" 







1 Background Level 



2 Mound Concentrations >> Background 



3 Cap Concentrations: 



a >Background 

 b =Background 

 c < Background 



4 Surface Sediments Approach Background Levels 



Deposition 



Deposition 



Time 



Figure 3-11. Geochemical model for capping of contaminated sediments 



Sediment Capping of Subaqueous Dredged Material Disposal Mounds 



