Mobile sediment in an urbanizing karst aquifer: Implications for contaminant transport

B.J. Mahler; L. Lynch; P.C. Bennett

doi:10.1007/s002540050434

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Mobile sediment in an urbanizing karst aquifer: Implications for contaminant transport

B.J. Mahler·L. Lynch·P.C. Bennett

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Abstract

Here we investigate geochemical characteristics of sediment in different compartments of a karst aquifer and demonstrate that mobile sediments in a karst aquifer can exhibit a wide range of properties affecting their contaminant transport potential. Sediment samples were collected from surface streams, sinkholes, caves, wells, and springs of a karst aquifer (the Barton Springs portion of the Edwards (Balcones Fault Zone) Aquifer, Central Texas) and their mineralogy, grain-size distribution, organic carbon content, and specific surface area analyzed. Statistical analysis of the sediments separated the sampling sites into three distinct groups: (1) streambeds, sinkholes, and small springs; (2) wells; and (3) caves. Sediments from the primary discharge spring were a mix of these three groups. High organic carbon content and increased potential to transport contaminants; the volume of these sediments is likely to increase with continued urbanization of the watershed.

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Environmental Geology Article

Source-reported bounding extent: 29.286398892934763° to 31.71882222408327° latitude; -100.96435546875° to -96.96533203125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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B.J. Mahler, L. Lynch, P.C. Bennett. 2000. Mobile sediment in an urbanizing karst aquifer: Implications for contaminant transport. https://doi.org/10.1007/s002540050434

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