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7. We can be confident of these statements based on existing 

 experience in the exploration for hot vents in the deep sea. 

 These occur only in volcanically active areas remote from the 

 abyssal plains. Although large volumes of hot water (600°F) 

 laden with heavy metals are being expelled, significant effects 

 are restricted to a few hundreds of feet laterally around the 

 vent sites and perhaps a thousand feet in the water column 

 above. There is absolutely no manifestation at the sea surface. 

 In fact vent fields are quite difficult to find! The exploration, 

 navigation and monitoring techniques discussed above for the 

 waste sites are exactly those used to study vents. 



