of the Endeavor began on February 21, 1911 , to delineate the extent of the 

 bottom contamination in the vicinity of the sunken bow section of the 

 Argo Merchant. Further field programs are planned by NMFS to continue the 

 long-term assessment of the spilled oil on the ecology of Nantucket Shoals and 

 Georges Bank. 



Prelininary chemical analyses for oil content of all water and sediment 

 samples taken up until February 12, 1977, have been completed. Selected 

 samples of fish, shellfish, water, and sediments have been sent to the NOAA 

 National Analytical Facility in Seattle, Washington, for more detailed study. 

 Biological studies based mainly on sampling at the six stations occupied 

 during the first cruise of the Delaware II (DE 76-13) are being carried out by 

 NMFS scientists. Neither the chemical nor biological studies have been 

 completed. Work is continuing by all concerned toward final assessment of the 

 fate and impact of the oil spilled from the Argo Merchant. With these cautions 

 in mind, the following prelim-lnary results are presented: 



o The oil from the Argo Merchant stayed on the ocean surface, with 

 the exception of the "cutter stock," which entered the water 

 column, and an as-yet undetermined amount of whole oil that was 

 mechanically worked into the bottom in the immediate vicinity of 

 the wreckage. The cutter stock, which comprised 20 percent of 

 the oil, was found in the water column in concentrations up to 

 250 parts per billion. The highest levels were observed only 

 beneath fresh oil slicks, and were reduced to background levels 

 by turbulent mixing in a few days. 



o Oil in significant amounts has not been found in the sediments to 

 date, except within 10 miles of the bow section, where concentra- 

 tions up to 100 parts per million were measured. 



o Most of the oil remained on the surface and moved offshore under 

 the influence of the prevailing west winds. Surface oil was never 

 observed north of 41°21' or west of 70°10' , nor was it observed 

 within 15 miles of any land. Modeling efforts were successful in 

 predicting the offshore movement of the surface oil, primarily 

 because the movement was controlled by predominantly offshore 

 winds while the complicated circulation of the nearshore areas 

 and Nantucket Shoals played only a minor role. 



o There is evidence of oil contamination in fish, shellfish, ichthyo- 

 plankton, and zooplankton populations in the area of the spill. 

 Mortalities of developing cod and pollock embryos in eggs contam- 

 inated with oil were observed. No. 6 fuel oil caused significant 

 mortalities of cod embryos in laboratory experiments conducted by 

 NMFS and collaborating scientists from EPA and the University of 

 Kiel. Noticeable decreases in the abundance of sand launce larvae, 

 which may have been caused by oil, were observed in the spill zone. 

 Large numbers of zooplankters , which are an important food of 

 larval and adult fish, were contaminated with petroleum hydro- 

 carbons similar to No. 6 fuel oil, indicating impact on an 

 important pathway in the food web of the Nantucket Shoals ecosystem. 

 The extent of this impact is under investigation. Much of the oil 



