1 DR. BUTMAN: Okay. 



2 DR. TEAL: I think that is a reasonable conclusion from this 



3 1 ittle exercise. 



4 DR. BUTMAN: I would say two things: that those are much larger 



5 numbers than people have seen on the shelf and if you drilled 100 wells 



6 like that, then you could start saying it could be important. 



7 I don't know what the toxicity levels are, but you are starting to 



8 be--if it's 20 parts per million-- 



9 DR. TEAL: Jerry said there was no measurable--no indication of 



10 barium toxicity even right under the rigs. 



11 DR. BUTMAN: This isn't barium. This is chromium. 



12 DR. TEAL: Jerry has never seen any effects of chromium or barium. 



13 DR. BUTMAN: He's also never seen an increase. He's never seen 



14 any increase, has he? Has he seen no effects in organisms that were 



15 exposed to chromium? 



16 DR. TEAL: They layered the mud on top of the sediment and put the 



17 animals into it. 



18 DR. RAY: In the laboratory work, the maximum accumulation factor 



19 we have been able to see with chromium has been about a 5- to 7-fold 



20 increase in the organisms, and that's the maximum we've ever seen. 



21 In the work that we have done and that EPA has done, they have not 



22 been able to come up with a good correlation between chromium and the 



23 toxic effects measured in the organism. The only component of the 



24 drilling fluids that they've ever been able to come up with as a good 



25 correlation between toxicity and the material has been hydrocarbon 



26 levels. 



27 If you have a lot of diesel in the mud, you find a good 



28 correlation, you know, about .8 or .9 but with the chromium experiments 



29 that were done, they couldn't get above a factor of about .2 or .3, 



30 somewhere in that range was the best correlation they could come up with 



31 between chromium and toxicity from the work that's been done. 



32 A lot of the bioaccumulation studies, the bioaccumulation factors 



33 were lower, maybe one- or two-fold. I think the maximum I have ever 



297 



