are primarily due to the increased turbidity and noise associated with 

 traffic and drilling. These effects were discussed in the preceding 

 section, "Site access by canal" and will not be considered further in 

 this discussion. Drilling activities require one to three months. Test 

 results indicate whether the well should be put into production or capped 

 and shut down. 



2. Primary ecological alterations 



2.1 Loss of vegetation in and around wellsite due to excavation and 

 covering 



2.2 Creation of a water environment about 3 m (8-10 ft) deep 



2.3 Increases in concentrations of suspended sediments and dissolved 

 nutrients 



2.4 Possible alteration of water flows due to fresh spoil disposal 



2.5 Introduction of toxic materials to water system 



2.6 Extended displacement of wildlife from immediate area 

 3. Attribute alterations 



Construction of the wellsite is usually an extension of construction of 

 the access canal; the dredge merely continued operation, disposing of 

 fresh spoil in the water or on adjacent land. This work removes vegeta- 

 tion, insects, and early life forms of associated consumers from a 

 maximum of 0.625 ha or 1.5 acres. This removal represents a loss of food 

 and cover for all remaining consumer groups. 



Short-term increases in suspended sediments and nutrients result from 

 construction activities. Longer-term increases resulting from erosion of 

 wellsite banks are of minor consequence. Neither the short-term nor the 

 long-term effect usually has a significant impact on the adjacent systems. 

 The fresh spoil may influence water flows on adjacent lands by isolating/ 

 filling depressions or blocking small drainages. The effects are usually 

 localized and insignificant when compared to the remaining unaffected land- 

 form. 



Replacement of land by bodies of standing water is essentially a tradeoff 

 of terrestrial organisms for aquatic organisn.s. Aquatic invertebrate and 



302 



