『Abstract
Utilizing geographic information systems (GIS) and statistics,
objectives of this study were to evaluate: (a) the spatial distribution
of nitrate concentrations in groundwater, and (b) associations
between nitrate concentrations and: proximity to playa lakes,
hydraulic conductivity of soil, well depth, and land use in the
High Plains Aquifer, Texas. Data were compiled from wells sampled
during 2000-2008. Nitrate concentrations in approximately 9% of
wells exceeded the maximum contaminant level for drinking water.
Concentrations were generally higher beneath urban and agricultural
land, under permeable soil, and in shallow wells (especially in
the southern part of the study area). However, concentrations
were lower near playa lakes. While playas focus recharge to groundwater,
denitrification in reducing environments lower nitrate concentrations
beneath them. This study identifies areas vulnerable to nitrate
contamination that warrant continued monitoring and mitigation
efforts.
Keywords: Nitrate; Groundwater; Playas; High Plains Aquifer; Texas』
Introduction
Study area
Methods
Results and discussion
Conclusion
References