The quality of our nation's waters: water quality in the Principal Aquifers of the Piedmont, Blue Ridge, and Valley and Ridge regions, eastern United States, 1993-2009

Abstract

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Towards Understanding Factors Affecting Arsenic, Chromium, and Vanadium Mobility in the Subsurface

“…Increasing distance blow the water table can promote development of more suboxic to anoxic and more alkaline conditions, as reductants and other reactive minerals are encountered ( Figure 1 ). In discharge zones characterized by low topography in unconfined aquifers, groundwater flow can be significantly upward-directed, bringing more evolved, anoxic waters closer to the land surface [ 29 ].…”

“… Conceptual model showing geochemical evolution of groundwater in the saturated and unsaturated zones, including the hydrogeochemical factors that influence the contaminant chemistry at multiple scales. Dashed lines indicate lithologic boundaries (modified from [ 27 – 29 ]). …”