duration of inundation decreases. The total area affected is site 

 specific and could range from insignificant to highly significant 

 when compared to the total area of salt marsh. Consumers that 

 depend upon smooth cordgrass and its epiphytes for food and/or cover 

 may ultimately increase or decrease. 



The amount of detritus exported to the adjacent estuarine system is 

 directly proportional to the standing crop of smooth cordgrass. If 

 the affected area is close to the water's edge, the frequency of 

 inundation and detritus export may remain unchanged. However, the 

 depressions allow faster movement of water in both directions. This 

 increases turbidity and decreases the efficiency of the detritus- 

 filtering mechanism of the salt marsh. Thus a net increase of 

 exported detritus could result. Net amounts of nutrients and sedi- 

 ment probably would not change significantly. 



If the affected area is further removed from the estuary where 

 isolated ponds may exist, intramarsh circulation could be affected. 

 Depressions could connect individual water bodies and increase the 

 intermixing of their contents. Waterfowl and wading bird use would 

 be expected to increase in these new depressions with standing 

 water. At the ecosystem level, however, this increase is slight. 



The degree and significance of wildlife displacement resulting from 

 gravity-meter surveys are slight. This is because of the small 

 number of people, lack of noise, and short period of time (usually 

 one day) required to complete a survey. 



4. Key attribute alterations 



The potential alteration which could lead to a significant impact on 

 the ecosystem is the creation of depressions in the land surface. 

 Effects which are long term and large in areal extent may result 

 from induced changes in waterflow regimes. These effects, of 

 course, can occur only if buggies or other surface vehicles are 

 used. As discussed above, the total area (and thus, the kinds and 

 numbers of consumers) affected is site specific. 



Site access by leveed road. 

 1. Activity sequence 



Surveyors enter the marsh by marsh buggy, by foot, or by truck (on 

 firm, soils), stake the route, and leave the area. The staked route 

 may or may not be the most direct pathway to the wellsite location. 

 A dragline with board mats enters the site to excavate a continuous 



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