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The watershed of Fivemile Creek, a tributary to the Locust Fork of the Black Warrior River, is located north of Birmingham, Alabama. Historical coal mining areas border the creek, and the creek and many of its tributaries are affected by acid mine drainage. In addition, current and past industrial and urban land use in the upper watershed may compound the effect on water quality in the stream.
The U.S. Geological Survey, in cooperation with the City of Tarrant, the Black Warrior-Cahaba Rivers Land Trust, and the Jefferson County Commission conducted a water-quality assessment of twelve sites along Fivemile Creek during 2003-2005. Water samples were analyzed for basic physical and chemical properties and concentrations of major ions, nutrients, chlorophyll a, pheophytin a, fecal indicator bacteria, organic wastewater compounds, pesticides, trace elements, and
semi-volatile organic compounds. Bed sediment samples were analyzed for concentrations of trace elements and semi-volatile organic compounds. Benthic invertebrate communities were evaluated for taxonomic composition and relation to
water-quality conditions.
Collected data were compared to established criteria and were assessed spatially to note areas of concern for human or aquatic community health in the Fivemile Creek watershed. These comparisons were made for some nutrients, pesticides and trace elements in water and for certain trace elements and semi-volatile organic compounds in bed sediment. Though no criteria exist for most of the organic wastewater compounds (some of which are known endocrine disruptors), detections of these compounds may be used to identify locations that may be receiving wastewater contamination. Endocrine-disrupting wastewater compounds may be of particular concern to aquatic community health.
Metal concentrations in sediment samples were determined by X-ray fluorescence (XRF) spectroscopy. These results were compared to laboratory-determined concentrations to assess the usefulness of the XRF spectroscopy as a screening tool for sediment quality.
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