ATT 
the weirs often creates a massive turbid plume. Moreover, it is this fine 
material to which many pollutants are attached. And in some instances the 
oxic conditions free the metals where their environmental activity is in- 
creased. 
A possible solution to this problem which has more than one environmental 
advantage is to employ sea-going barges for transport. In many instances 
the hopper dredge is not only the dredger but the transporter of the ma- 
terial to the dumpsite. During this period of transport it is out of ac- 
tion, thus prolonging the dredging operation. A possible solution, which 
has been used successfully, would be to pump the hopper material directly 
into a sea-going barge without the overfill. The small decrease in sedi- 
ment carried per load would very likely be compensated for by virtue of 
keeping the dredger on the dredging job 24 hours a day. 
Moreover, these barges could be equipped to either shunt material below the 
zone of maximum phytoplankton production or to pump very polluted material 
into pits on artificial islands. 
