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Downstream Changes in Bed-sediment and Streamwater Metal Concentrations along a Watercourse in a Rehabilitated Post-industrial Landscape in South Wales

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Over 250 years of metal smelting in Swansea (South Wales) left metal-rich slag across the Nant-y-Fendrod valley floor and aerial metal pollution over the wider landscape. Reclamation since 1965 included: (1) partial removal of spoil, flattening the rest and capping it with topsoil, (2) culverting watercourses and creation of two flood-relief lakes and (3) revegetation of the aerially polluted landscape. This paper assesses downstream changes along the Nant-y-Fendrod stream–lake system in metal levels of (a) fine bed-sediment and (b) streamwater and seepages. In the upper, ‘aerial-pollution zone’ total Zn, Cu, Pb and Cd in surface bed-sediment increase marginally within the first lake to 892, 207, 212 and 7.2 mg/kg, respectively. Farther downstream, Cu and Pb rise sharply, and Zn and Cd progressively, to 12,853, 595, 871 and 155 mg/kg, respectively, as the stream traverses the ‘capped metal-rich waste zone.’ Zn and Cd reach 22,671 and 229 mg/kg, respectively, in the second lake, before falling 35–56% below its outlet. Streamwater metal levels rise (but seepage metal concentrations remain stable) in most storm events, though patterns (including whether levels are reduced downstream of the lake) vary with antecedent conditions. Possible interactions between seepages, bed sediment and streamwater metal dynamics are explored.

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  1. Becker, A., Klock, W., Friese, K., Schreck, P., Treutler, H. C., Spettel, B., et al. (2001). Lake Süsser See as a natural sink for heavy metals from copper mining. Journal of Geochemical Exploration, 74, 205–217.

  2. Bird, S. C. (1987). The effect of hydrological factors on trace metal contamination in the River Tawe, South Wales. Environmental Pollution, 45, 87–124.

  3. Blake, W. H., Walsh, R. P. D., Barnsley, M. J., Palmer, G., Dyrynda, P., & James, J. G. (2003). Heavy metal concentrations during storm events in a rehabilitated industrialized catchment. Hydrological Processes, 17, 1923–1939.

  4. Blake, W. H., Walsh, R. P. D., & Barnsley, M. J. (2003). Relating mineral magnetic measurements to sediment quality in a remediated contaminated catchment: The significance of heavy metal delivery mode and water–sediment exchange dynamics in a small urban lake. Journal of Physique IV France, 107, 193–196.

  5. Bradley, S. B., & Lewin, J. (1972). Transport of heavy metals on suspended sediments under high flow conditions in a mineralised region of Wales. Environmental Pollution. Series B. Chemical and Physical, 4, 257–267.

  6. Bridges, E. M., & Morgan, H. (1999). Dereliction and pollution. In R. A. Griffiths (Ed.), The city of Swansea: Challenges and change (pp. 270–291). Swansea: University College of Swansea.

  7. Che, Y., He, Q., & Lin, W. Q. (2003). The distribution of particulate heavy metals and its indication to the transfer of sediment in the Changjiang Estuary and Hangzhou Bay, China. Marine Pollution Bulletin, 46, 123–131.

  8. Environment Agency (1998). National sampling procedures manual, vol. 25, London: Environment Agency.

  9. Hudson-Edwards, K. A., Macklin, M. G., & Taylor, M. P. (1999). 2000 years of sediment-borne heavy metal storage in the Yorkshire Ouse basin, NE England, UK. Hydrological Processes, 13, 1087–1102.

  10. Lambert, C. P., & Walling, D. E. (1988). Measurement of channel storage of suspended sediment in a gravel-bed river. Catena, 15, 65–80.

  11. Schindler, P. W. (1991). The regulation of heavy metal concentrations in natural aquatic systems. In J. P. Vernet (Ed.), Heavy metals in the environment (pp. 95–120). London: Elsevier.

  12. Shu, J., & Bradshaw, A. D. (1995). The contamination of toxic waste. I. Long term metal movements in soils over a covered metalliferous waste heap at Parc lead–zinc mine, North Wales. Environmental Pollution, 90, 371–377.

  13. Walsh, R. P. D., Thornton, G. J. P., Boulton, M. A., Ellis, A. C., & Palmer, G. T. (2000). Changes in heavy metal pollution dynamics in the Nant-y-Fendrod stream since 1966 with rehabilitation of the Lower Swansea Valley. British Hydrological Society Occasional Paper, 11, 331–338.

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This work was supported by NERC Grant GST/02/2240 within the Urban Regeneration and the Natural Environment (URGENT) Thematic Programme. The authors thank Dave Johnston (Environment Agency), Huw Morgan and Andrew Cluckie (Swansea Council) for historical site information; Phil Bevan for chemical analysis; and Gabi Palmer, Peter Willmont and John Garbett-Davies for aid with fieldwork.

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Correspondence to R. P. D. Walsh.

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Walsh, R.P.D., Blake, W.H., Garbett-Davies, H.R. et al. Downstream Changes in Bed-sediment and Streamwater Metal Concentrations along a Watercourse in a Rehabilitated Post-industrial Landscape in South Wales. Water Air Soil Pollut 181, 107–113 (2007).

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  • Bed sediment
  • Water quality
  • Heavy metals
  • Contaminated land
  • River pollution