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Ground Water Study Design

 

Map of LTEN study unit With Eastern highland Rim highlighted

SUBUNIT SURVEY

 

Ground-water study components in the NAWQA program consist of subunit surveys, land-use studies, and flowpath studies.  Subunit surveys are conducted to characterize water quality in major aquifers in the study unit. About 30 randomly located, existing wells are sampled for analysis of major ions, nutrients, pesticides, volatile organic compounds, trace elements, and radon to describe the occurrence and distribution of these constituents in a given aquifer and geologic setting. The first subunit survey in the LTEN was conducted in the Eastern Highland Rim subunit.

 

LAND-USE STUDY

 

Land-use studies are conducted to characterize the quality of recently recharged ground water in an aquifer that may be affected by a particular land use. Generally, these studies are conducted in urban and agricultural land-use settings. Land-use studies emphasize shallow aquifer systems so that the effects of land use and environmental setting can be more accurately assessed.  About 30 wells are installed in areas that have been stable with respect to the land use of interest for at least ten years. An agricultural land-use study is planned for the Eastern Highland Rim subunit.

 

FLOW PATH STUDY

 

The scale on which flow path studies are conducted is smaller than the other two ground-water study components.  Flow path studies attempt to understand the processes that affect shallow ground-water quality in a given setting by collecting water quality data in both the vertical and horizontal directions of ground-water flow along a presumed flow path.

 

 


Last modified: Thu Jan 19 12:46:39 2000