Regional Transect Study - northern High Plains (cont.)
Objectives:
Measure vertical gradients in the chemistry and age of water in the Ogallala
Formation, northern High Plains aquifer.
Provide a better understanding of contaminant sources/sinks in the Ogallala
Formation.
Identify principal geochemical reactions controlling water chemistry.
Develop an understanding of ground-water residence times and recharge
rates in the Ogallala Formation.
Approach:
Install and sample nested wells at 4 sites located along a regional flow
path and have large saturated thicknesses (see
map). Each nested well site will have a well screened at the water table,
base of the aquifer, and two intermediate depths.
Timing:
2005-6 UPDATE: The first of two reports was published in Environmental
Science & Technology in 2006.
Planned 2007:The second report, a USGS Scientific Investigations Report,
will be published
Targeted Constituents:
Physical parameters, major ions, nutrients, trace elements, radon, pesticides,
DOC, and multiple chemical and isotopic tracers needed to address the above
objectives.
