Some portion of the garbage rift objects are quasi buoyant, in that they do float, but below the surface, all the way down to 40 meters on average. By adding a few venturi air nozzle pipes, that portion of the plastic mass could be drawn up to be swept between the surface collection booms. Also, I'm wondering on both the feasibility and need, frankly, for recycling the salvaged plastics. They will be in poor shape physically, chemically degraded, some pieces are quite tiny (the most harmful - fish ingest them accidently) and the cost versus return would be quite poor, even if the entire operation is PV/wind powered. It may even run at a bad loss. Just collect the crap, get shipping companies to do tax write-off hauling jobs of it back to shore, and it can then be processed into concrete mixes and road paving aggregate.