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NATURE AND APPLICATION OF SPECIAL CARE MEASURES 
RELATIONSHIP TO DECISION PROCESS 
The concept of special care measures applies to three phases of the dredg- 
ing/disposal process, viz., 
(1) To methods of disposing of dredged material in the marine 
ecosystem. : 
(2) To procedures to be followed in the dredging and transport 
of bottom sediments. 
(3) To decisions involved in selecting the location and other 
characteristics of dumpsites. 
Obviously there can also be particular combinations of items 1 and 3 
above. 
SPECIAL CARE MEASURES OF DISPOSAL 
CLEAN MATERIAL CAPPING « 
Description of the Technique 
In clean material capping (CMC) relatively large volumes of polluted dredg- 
ed material are emplaced and then covered with a reasonably thick (no less 
than one meter) blanket of unpolluted or clean sediment. The technique's 
rationale argues that the "cap" will prevent transport of the polluted ma- 
terial and that it will also be thick enough to accommodate the needs of 
burrowing benthos. Hence they will not drill into the polluted core, which 
action could permit pollutants to reach the sediment/water interface 
through the process of bioturbation. 
