According to the SHL report, patterns of circulation obtained from 

 its drifter studies indicate a transport mechanism which can account for 

 the distribution of organic materia-l, coliform bacteria, and heavy metals 

 found in the sediments and waters of the Bight. This claim, however, is 

 disputed. According to the SAC review (SAC, 1972), the SHL study did not 

 incorporate the findings of the water circulation patterns, preliminary 

 as they may be, in an analysis of the distribution of important constituents 

 of the discharged waste in either the water column or the benthos. The 

 information on circulation, therefore, cannot be correlated with conclusions 

 on quality conditions. The SHL water-circulation study, for example, can- 

 not explain the existence of the area east of the diamping grounds which 

 has carbon-rich sediments, but is separated with no continuums from the 

 disposal area. Similarly it cannot quantify the degree of dilution and 

 dispersion these waste constituents undergo, if indeed their transport is 

 in the directions indicated by the drifters. 



The circulation data accumulated from the Bight is insufficient to per- 

 mit quantitative studies of waste dispersion. Results with seabed and sur- 

 face drifters, although of some value in indicating net surface and bottom 

 movements of the water, are of questionably validity. The actual path 

 of these drifters and time of travel are not known, and their net movement 

 cannot be correlated to sediment transport and water quality. Return of 

 drifter to shore is not necessarily proof that harmful pollutants will 

 also end up on shore. The path of the drifters is not direct, and the 

 time of travel is long. Even if pollutants are assumed to follow the 

 same path as the drifters, the degree of dilution to surrounding waters 

 will be great, reducing adverse effects on water quality. 



The dispersion studies of the SHL would have been more meaningful if 

 the study of the hydrography of the Bight was supported by geostrophic 

 flow calculations. Also a direct comparison of surface drift with magni- 

 tude of the annual wind stress in different directions, would have been 

 helpful. In a study of surface currents off the Oregon Coast (Wyatt et al, 

 1972), wind stress data was correlated effectively with surface currents 

 and net water transport. 



Although the SHL studies of the water circulation have not been suf- 

 ficient to correlate with waste dispersion following dumping in the Bight, 

 the current measurements obtained, provide a basis for further study, such 

 as a time series analysis. In conjunction with the drift studies, such an 

 analysis (SAC, 1972), would indicate, at least in a preliminary fashion, 

 the circulation pattern of the area, and the significance of the various 

 factors affecting the circulation. Specifically, it would help define 

 the variance of the different inputs. This is important in respect to 

 effects of transport processes of the system in distributing the wastes 

 throughout the Bight. Additional analysis of these data would be an im- 

 portant input to a preliminary hydrodynamic model of the area which could 

 correlate effectively water circulation data with the temporal and spatial 

 distribution and transport of waste constituents. Such a model should 

 incorporate dispersion and advection terms, reactions that affect the 



