detectable level of fluorescences is equivalent to 2 micrograms of oil con- 

 tained in 5 cubic centimeters of sediment. 



Ultraviolet fluorescence screening of sediment samples . A measured vol- 

 ume of sediment (10 cubic centimeters) is extracted with 5 milliliters of 

 spectroquality hexane by stirring the slurry for 1 minute. The extract is 

 then removed and analyzed by the synchronously scanning fluorescence techni- 

 que used for the water samples. Comparison of the sample spectrum with that 

 of the reference oil spectrum at various concentrations indicates the rela- 

 tive concentration of oil present in the samples. The reference oil is the 

 same as that being used for the water samples. 



Preliminary Results 



All sediment samples have been screened by the thin-layer chromato- 

 graphic procedure. Samples collected on the Evevgveen, Delaware II 76-13, 

 and Delaware II 77-01 cruises indicate extremely low levels of petroleum 

 concentrations, with a majority of these samples having no fluorescent blue 

 spot. Sediment samples collected on Oceanus cruises 19 and 20 indicate 

 substantially higher levels of petroleum concentrations than those obtained 

 on the Evergreen and Delaware II cruises. The samples collected on Oaeanus 

 cruise 20 at stations 1 and 5 have the highest level of petroleum concentra- 

 tion. The PHC found at station 1 is a light distillate, while that found at 

 station 5 is a heavy fuel oil that appears unrelated to the Argo Merchant 

 oil. Splits of significant samples from all cruises are being forwarded to 

 the NCAA National Analytical Facility in Seattle, for complete GC-MS analysis 

 under the direction of W. MacLeod. Petroleum concentration levels in these 

 samples will also be determined by ultraviolet fluorescence and combined high 

 pressure liquid chromatographic and fluorescence spectroscopic techniques by 

 the USCG Research and Development Center and by Mississippi State University. 



Analyses of sediment and water column samples collected on the Endeavor 

 003 and 004 cruises are still in progress. Preliminary analyses of stations 

 occupied in the vicinity of the bow section of the Argo Merchant indicate 

 high levels of Argo Merchant oil in the sediment. Analyses of three sediment 

 samples collected at station G-43 on the Endeavor 004 cruise indicate concen- 

 trations higher than 50 parts per million based on wet sediment, with the 

 highest level found in grab 2 at station G-43. Tables 3-4 and 3-5 summarize 

 the preliminary sediment analysis data for samples collected in the vicinity 

 of the bow section of the Argo Merchant. All concentrations are approximate 

 levels of concentrations based on the December 19 sample collected by J. 

 Mattson and J. Gait of NCAA. Analysis of water column samples collected on 

 the Endeavor 004 cruise, incidentally, again indicate no presence of poly- 

 aromatic hydrocarbons. 



3.2.4. Summary 



If the Argo Merchant oil has entered the water column in any significant 

 amounts, only the light aromatic fractions have done so. There is no evi- 

 dence to date of any significant amounts of the heavy polyaromatics. Anal- 

 yses are in progress to determine if there is a relationship between the 



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