Swati Ganveer, Kamal Lochan Pruseth, David Anand Aind
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引用次数: 0
Abstract
This study investigates the source-sink dynamics and hydrogeochemical controls governing arsenic fate and transport within a fractured crystalline aquifer system. The hydrogeologic framework is characterized by spatial heterogeneity in redox conditions and persistent undersaturation with respect to key Fe-, sulfate-, and Ca-bearing mineral phases. Mineralogical characterization identifies arsenopyrite and cobaltite as the primary geogenic sources; oxidative weathering of these sulfide phases drives the continuous release of arsenic. Aqueous speciation modeling reveals a predominance of As(V) and Fe(III) species, with minor As(III) occurring within reducing microenvironments. Persistent undersaturation of Fe- and As-bearing minerals, together with other attenuation-controlling phases, suggests limited potential for secondary mineral precipitation, while allowing arsenic to remain predominantly in the dissolved phase. Weak correlations between arsenic and hydrochemical gradients indicate that contaminant distribution is highly heterogeneous and controlled by the occurrence of mineralized zones. The results demonstrate that persistent arsenic mobility in fractured crystalline aquifers can occur under predominantly oxidizing conditions through sustained sulfide weathering combined with limited attenuation capacity within the aquifer system.
期刊介绍：
The Journal of Contaminant Hydrology is an international journal publishing scientific articles pertaining to the contamination of subsurface water resources. Emphasis is placed on investigations of the physical, chemical, and biological processes influencing the behavior and fate of organic and inorganic contaminants in the unsaturated (vadose) and saturated (groundwater) zones, as well as at groundwater-surface water interfaces. The ecological impacts of contaminants transported both from and to aquifers are of interest. Articles on contamination of surface water only, without a link to groundwater, are out of the scope. Broad latitude is allowed in identifying contaminants of interest, and include legacy and emerging pollutants, nutrients, nanoparticles, pathogenic microorganisms (e.g., bacteria, viruses, protozoa), microplastics, and various constituents associated with energy production (e.g., methane, carbon dioxide, hydrogen sulfide).
The journal''s scope embraces a wide range of topics including: experimental investigations of contaminant sorption, diffusion, transformation, volatilization and transport in the surface and subsurface; characterization of soil and aquifer properties only as they influence contaminant behavior; development and testing of mathematical models of contaminant behaviour; innovative techniques for restoration of contaminated sites; development of new tools or techniques for monitoring the extent of soil and groundwater contamination; transformation of contaminants in the hyporheic zone; effects of contaminants traversing the hyporheic zone on surface water and groundwater ecosystems; subsurface carbon sequestration and/or turnover; and migration of fluids associated with energy production into groundwater.
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