1 DR. NEFF: Right, exactly. The one instance I mentioned, I think 



2 it was just one location had that kind of increment. 



3 DR. COOPER: In your experiments with these juvenile lobsters as a 



4 function of barium, did you also have any of your other trace metals, 



5 copper, zinc, iron in there as well? 



6 DR. NEFF: What they were exposed to was what we call the 



7 settleable fraction of drilling mud. That's the stuff that settles more 



8 rapidly than the light clay fraction. So, all the metals that would 



9 normally be in these drilling muds were there. 



10 These were natural muds from the Gulf of Mexico, because that's 



11 where active drilling was going on at the time. They were field muds, 



12 they weren't made in the laboratory. 



13 DR. COOPER: Lobsters are notoriously and extremely sensitive to 



14 zinc and copper in very, very low concentrations. 



15 DR. NEFF: The evidence we've seen so far is that these metals 



16 like zinc and copper are not present in ionized form in ionic copper. 



17 Most of the copper is associated with sulfide minerals in the solid 



18 phase, so you don't get an increase in the ionic copper. 



19 The key here is the form of the metals. You do get elevated metal 



20 concentrations, but most of them are in forms that are like the metal in 



21 your pocket in coins, it's in an unavailable form. 



22 DR. MACIOLEK: Jerry, the studies that you summarized on impacts 



23 on benthic communities, can you tell us what water depth those 



24 communities were in that were significantly impacted? When I talked 



25 about recovery within a year, was that in terms of species diversity or 



26 abundances? 



27 DR. NEFF: In the mid-Atlantic, the water depth was about 100 



28 meters or so. That was a fairly quiescent area of high-clay fraction in 



29 the sediments. Obvious evidence of significant accumulation of drilling 



30 fluids. There was basically a mud and cutting pile next to the 



31 platform. 



32 The major indices there were species abundance and diversity and 



33 so forth, species composition. In some locations right near the 



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