show similar effects on the organisms present. Specifically, the effects of 

 metals and petroleum on bacteria are transient and short term, owing to 

 the population's rapid adaption (approximately 3 days) to imposed 

 stress. Consequently, measurement of hetrotrophic activity is probably 

 not reliable as an indicator of pollutant stress after the first few days of 

 exposure. 



Measurements of respiration/excretion rates in zooplankton show lit- 

 tle reaction to pollution stress. However, other indexes of metabolic 

 well-being such as egg production and feeding rate are sensitive indica- 

 tors of stress at sublethal levels. In general, small zooplankton, regard- 

 less of species, are more sensitive than larger organisms. The conse- 

 quence of pollution on higher trophic levels, for the most part, remains 

 unsolved. 



The ACE continues marine research and experimentation activities 

 as part of its Dredged Material Research Program. ACE is currently 

 monitoring four open-water dredged material disposal sites in Lake Erie 

 (off Ashtabula. Ohio.) the Pacific Ocean (off the mouth of the Columbia 

 River), the Gulf of Mexico (off Galveston. Texas), and in Elliot Bay (off 

 Seattle, Washington). These sites are representative of marine, estuarine 

 and freshwater locations. The dredged material is obtained from routine 

 channel maintenance projects. Material discharged at these sites ranges 

 from nonpolluted channel shoals to polluted harbor sediments. Dredging 

 is by hooper and mechanical dredge with hooper and barge discharge. 

 The objectives of the ACE investigations are to provide definitive infor- 

 mation on the environmental impact of dredging and discharge in 

 coastal areas and inland waterways and to develop new or improved dis- 

 charge practices. 



To accomplish these tasks, multidisciplinary field studies have been 

 designed involving investigations of water quality, current patterns and 

 other hydrodynamic processes, sediment chemistry, and sedimentary 

 dynamics. The first year of these 2.5-year studies has been completed. 

 This phase involved the collection of baseline data and sampling. Con- 

 trolled disposal and continued baseline monitoring are being conducted 

 during the second year (Phase II) of the study. The identification of 

 cause-and-effect relationships will be possible throughout the re- 

 mainder of the study. The final phase of the investigations will consist 

 of compiling the results, evaluating identified problems, and formulating 

 recommendations for environmentally compatible discharge techniques. 

 These effects in the four selected areas, in addition to other smaller scale 

 physical and chemical investigations, will provide useful data to other 

 interested agencies and benefit ACE missions. 



The United States Navy (USN), like ACE and USCG, conducts water 

 quality research primarily in support of its operating responsibilities. A 

 significant USN research effort is now being directed toward the use of 



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