The usual pattern in the bulk sediment results was a sharp increase after 

 the commencement of drilling and a return to background or near background 

 levels at the end of 9 months. There was little discernible change over time 

 in the fine fractions. There appeared to be a lack of correlation between 

 mercury and barium. 



CONCLUSIONS 



There is little, if any, evidence of biological effects in these three 

 locations. Measurements of total metals in organisms can be misleading. 

 Detailed analysis of the actual fate of metals within the organism are needed 

 to more accurately determine biological impact. 



QUESTIONS 



Teal and Butman asked about the lack of mercury/barium correlation. The 

 speaker noted that there is some evidence of a cadmium-barium correlation in 

 tests off California but that it only appears at the stations immediately 

 downstream, at distances less than or equal to 400 m. The regulatory agencies 

 are interested in mercury and cadmium although mercury remains insoluble and 

 is not bioavailable. Cadmium is slightly soluble and has shown some limited 

 availability for uptake by organisms. 



Cooper asked about effects on marine life. Ray saw no biological effects 

 beyond the immediate wellsite. In intracellular analysis of animal tissue, 

 the barium concentrations in the cytosol {soluble fraction) is one to two 

 orders of magnitude below the threshold levels of calcium (Ca++), and thus 

 probably would cause no toxic effects. 



He re-emphasized the need to look at detail: the fine fraction in the 

 sediments and the different parts of the organism--in order to come to any 

 meaningful conclusions. 



- 34 



