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dredged material or to procedures to be followed in the dredging end trans- 
port of bottom sediments or to deciSions in selecting the location and other 
characteristics of dumpsites. 
SPECIAL CARE MEASURES OF DISPOSAL 
CLEAN MATERIAL CAPPING 
In clean material capping (CMC) relatively large volumes of polluted dredged 
material are emplaced and then covered with a reasonably thick blanket of 
clean material. Availabale evidence indicates that CMC is an environmental- 
ly sound method by which to dispose of polluted dredged material. 
BORROW PIT DISPOSAL: ANOTHER CMC TECHNIQUE 
Another innovative approach to capping operations utilizes existing sub- 
marine borrow pits which have been made during sand mining. These pits are 
generally anoxic. The process involves dumping the polluted material into 
the pit and capping it flush with the ambient bottom with adjacent clean 
material. This process will actually enhance the benthic environment by 
removal of more or less abiotic pockets. 
SPLIT-SITE DISPOSAL 
Where huge volumes of dredged material are to be generated by major improve- 
ments to a port or harbor, it may be environmentally sound to utilize a dis- 
posal site that has a half dozen or so release zones. If both polluted and 
unpolluted material are to be generated in the improvement project, the pol- 
luted sites should be dredged first and dumped ad seriatum at the half dozen 
release zones. By careful management, this should permit downstream organ- 
isms in particular to depurate many of the toxicants without reaching heavy 
body burdens. Later, as the work on the project proceeds to new work, where 
the sediments are likely to be clean, each release zone can be capped. 
