63. Water may be obtained from the treated supernatant from the secon- 

 dary containment area, a tanker truck located onsite, or a branch off a nearby 

 water distribution system. The dilution water must be clean and free of any 

 debris that may cause mechanical pump problems and hender the effectiveness of 

 the polymer on the dredged material effluent. 



64. Injector and feed line. The injection system should distribute the 

 polymer uniformly throughout the water as it flows over the weir. The system 

 will distribute the polymer solution from a l-in.-diam polyvinyl chloride 

 (PVC) pipe at the leading edge of the weir. The PVC pipe must have 1/8-in.- 

 diam holes that will dispense the polymer along the entire weir length at a 

 uniform rate. The feed lines may be constructed of rubber hoses or PVC pipe. 

 However, a PVC pipe must be used for the polymer injection system. 



Static mixer 



65. The static mixer is an in-line mixer that will mix the polymer and 

 dilution water to the final desired concentration. These devices are commer- 

 cially available. 



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