4. Key attribute alterations 



The key attribute alterations associated with production phase activities 

 involve the direct long-term removal of productive plant assemblages and 

 those directly dependent consumer groups residing within the production/ 

 treatment complex site. Consumer response is a function of the areal 

 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 favorable habitats because of continuous opera- 

 tional and vehicle-associated disturbances. 



The chronic effects of persistent toxic materials, particularly brine, 

 may be more important than localized acute effects on local biotic 

 assemblages. 



Spills and cleanup . 



1. Activity sequence 



Accidentia! discharge of crude oil, gas, field brine, or other substances 

 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 intramarsh 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 contam- 

 inants. 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. 



2. Primary ecological alterations 



Alterations will vary according to the spill size, toxicity of the 

 chemical substances released, and cleanup methodology utilized. 



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