only minor benefits to consumer groups which previously utilized the site. 

 Birds, particularly waterfowl and wading species, contaminate their plum- 

 age by landing or wading in spilled oil. Bird mortality results from 

 exposure (due to a loss of insulation properties of the plumage) or inges- 

 tion of toxic petrochemical compounds (swallowed while the birds attempt 

 to clean oil from soiled feathers). Furbearers and other small mammals 

 within the impacted area may experience smiliar difficulties. 



Movement of men, marsh buggies, airboats, barges, outboards, and other 

 cleanup equipment over and through aquatic marsh areas disturbs soft 

 sediments, thereby increasing suspended sediments and dissolved nutrient 

 concentrations. Similar movements on firmer substrates cause partial 

 vegetation damage and rearrangement of surface configurations. Such 

 alterations occur within, as well as around, the actual spill area. Such 

 changes are temporary and restricted in nature. They are of little con- 

 sequence at the ecosystem level of consideration. 



Cleanup techniques involving all or some of the following procedures 

 include: (1) placement of floating booms or containment skirts; (2) dis- 

 persal and collection of absorbent/adsorbent materials; (3) excavation 

 and removal of contaminated plants and soils; and (4) application of 

 chemical dispersants or emulsifiers. Boom deployment by boat causes few, 

 if any, environmental alterations. Deployment and subsequent collection 

 of absorbent/adsorbent materials such as hay, straw, or specially manu- 

 factured plastic sheets is usually accomplished with manual labor. Site 

 alterations are restricted to vegetation trampling and small surface dis- 

 turbances. 



Cleanup of residual oil not removed with conventional collection tech- 

 niques is accomplished by burning the contaminated site. Producers, and 

 consumers which do not abandon the site, are removed. Removal of stand- 

 ing plant materials and sediments soaked with oils lowers the local land 

 elevation and could produce some new areas of standing water. The stor- 

 age of unavailable nutrients is decreased slightly, but probably not 

 enough to affect the ecosystem. Toxic components of the spilled material 

 are prevented from affecting existing or future biotic elements when 

 saturated substrates are excavated. It is generally agreed among investi- 

 gators that chemical oil spill emulsifiers, dispersant removers, etc. are 

 very toxic to aquatic life. Not only are the chemical agents toxic to 

 aquatic invertebrates and vertebrates, but synergistic reactions occur 

 which make a crude-oil/oil-spill-remover mixture much more toxic than 

 either component separately. 



Although cleanup activities may trample and crush extensive amounts of 

 uncontaminated vegetation, the most significant alterations of the cleanup 

 sequence are concerned with changes of the waterflow regime. Movement of 

 marsh buggies and earthwork equipment associated with constructing 

 emergency containment levees or drainage channels changes local land 

 topographic features. Intramarsh circulation patterns may be altered as 

 a result of drainage blockage (establishment of levees) or drainage 



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