Disturbance factors should be recognized as an important considera- 

 tion because they extend project impacts beyond the boundaries of 

 the immediate site. 



Key attribute alterations 



The key attribute alteration involves primarily the direct long-term 

 removal of productive plant assemblages and those directly dependent 

 consumer groups found within the production site. Consumer response 

 is a function of the area! extent of the change, the size of the 

 consumer's resource base, and its sensitivity to altered habitat 

 conditions. Sensitive wildlife species may abandon otherwise favor- 

 able habitats because of operational and vehicle-associated distur- 

 bances. 



The chronic effects of persistent toxic materials may be more impor- 

 tant than localized acute effects. 



Spills and cleanup. 



1. Activity sequence 



Accidental discharge of crude oil, gas, field brine, or other sub- 

 stances occurs as a result of equipment failure, improper equipment 

 operation, or human error. Built-in safety mechanisms, if present, 

 are activated automatically to limit the quantity of discharge. 

 Field personnel, once aware of the spill or leak, immediately 

 initiate procedures to confine discharges to the smallest possible 

 area. If the discharged materials enter open-water bodies or intra- 

 marsh channels, then floating oil booms or surface dams are 

 dispersed to contain the spill. Marsh buggies, air boats, and motor 

 boats may be used for deployment trips and personnel transport. 

 Skimmer or vacuum units mounted on trucks or barges may be used to 

 collect floating oil and other buoyant petrochemicals. Straw or hay 

 is used to adsorb smaller, less accessible quantities that vacuum 

 trucks cannot remove. Specially manufactured absorbant sheets may 

 be dispersed and then later collected by hand. Standing vegetation 

 coated with oil may be flushed with water pumped through high-pressure 

 hoses and hand cut and removed from the site or burned in place to 

 remove contaminants. Oil -contaminated muds may be excavated with 

 hand shovels or heavy machinery, depending upon site characteristics 

 and spill size. Special dispersion techniques may be necessary to 

 discourage use of contaminated areas by wildlife, primarily waterfowl 

 and wading birds. Removal of contaminants signals completion of the 

 cleanup phase and the beginning of site restoration procedures. 



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