investigation. Much of the oil in the copepods was in the form of fecal 

 pellets. These pellets are excreted into the water column, settle to the 

 bottom, and may be concentrated in benthic filter-feeders (mussels, scallops, 

 quahogs) . Adverse physiological effects were also observed in reduced re- 

 spiration of scallops, mussels, and in an ionic imbalance of blood serum of 

 blackback and yellowtail flounders. The implications of the above results 

 for long-term effects are unclear. Additional extensive surveys and labora- 

 tory tests be required to clarify preliminary findings. 



(5) The No. 6 fuel oil from the Avgo Mevchant formed pancakes of oil 

 which tended to increase in thickness as they aged. These pancakes were ob- 

 served to have flat bottoms and they did not appear to be tapered towards 

 their edges. The surface area impacted by oil was not solidly covered by a 

 continuous film of oil but rather by thick pancakes, very thin oil film 

 (sheen) and large open areas of water. Several direct measurements of the 

 velocity of the pancakes of oil relative to the surface water were obtained 

 which indicate that this differential velocity is about 1 percent of wind 

 speed in a downwind direction. The oil sheen appeared to be generated by the 

 oil in the pancakes and moved at a slightly lower speed. 



(6) Sufficient data were collected during the oil spill to allow the 

 generation of a data set which can be used for hindcasting the oil movement. 

 The collected data include meteorological observations, current observations 

 at several locations in the spill area, a time history of the area covered by 

 oil, as well as data on the amounts and fractions of the oil which entered 

 the water column as a function of time and space. Analyses of these data 

 will lead to the development of improved algorithms describing the fate of 

 oil. These algorithms can then be incorporated into predictive models. 



5.1 Oil Transport 



Under the influence of the predominant westerly winds and the wind- 

 induced surface currents, the oil spilled from the Avgo Mevchant moved in an 

 east-southeast direction from the site of the wreck on Nantucket Shoals out 

 past the Continental Shelf and became a part of the general circulation of 

 the North Atlantic Ocean. All indications are that the remaining oil will 

 not sink and will be present on the ocean surface for some time. This oil 

 has by now become a part of the "standing stock" of tar balls floating in 

 the North Atlantic. As such, they will tend to weather until the exterior 

 surface develops the characteristics of asphalt. The hard outer surface will 

 act as settling surfaces for barnacles, etc., while the interior of the 

 larger tar balls will retain much of the fluid consistency of the original 

 straight-run No. 6 fuel oil. 



Each day that the oil moved off the Continental Shelf and into the 

 Atlantic circulation pattern, the weather became less of a forcing factor 

 and the slick movement was dominated by baroclinic (general oceanic) cur- 

 rents. The waters over Nantucket Shoals and Georges Bank during the last two 

 weeks of December were vertically homogeneous, and the general westerly 

 current pattern described in BLM's EIS for Georges Bank did not appear to be 



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