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Ian Dennis' thesis download

Here are the chapters from Ian Dennis' thesis - from 2005, he worked with me at Aberystwyth from 2000 to 2005. He is still working at Aberystwyth and can be contacted at idd@aber.ac.uk

If you use material from it, please reference it as:

Dennis, I. D. (2005). The impact of historical metal mining on the river Swale catchment, North Yorkshire, U.K. Unpublished Phd Thesis, Institute of Geography and Earth Sciences, University of Wales, Aberystwyth.

Chapter 1
Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9



This investigation examines the impact of historical metal mining on the River Swale
catchment, North Yorkshire, U.K. Approximately 550,000 tonnes of Pb were extracted
from mines in the Swale catchment during the eighteenth and nineteenth centuries.
Mining and processing operations were relatively inefficient, leading to the discharge of
large quantities of metal-rich sediment into the fluvial system. The primary aim of this
thesis is to assess the physical and chemical impacts of the discharge of metals from
historical mining activities on the River Swale catchment as a whole. The dispersal,
storage and transfer of metal-rich sediment in formerly mined tributaries, floodplain and
flood sediments are evaluated, and the environmental consequences of mining are
A detailed geochemical survey of the River Swale catchment indicates that channel and
floodplain sediments within formerly mined tributaries exhibit extremely high
concentrations of Pb, Zn and Cd. Similar enrichment is observed in floodplain sediments
from throughout the catchment, suggesting that large volumes of material have been
transported from the tributaries and deposited on the Swale floodplain. Evidence from
contemporary flood sediments suggests that considerable quantities of metal-rich sediment
continue to be cycled through the system almost 100 years after the cessation of mining
operations. Sediment budgeting suggests that 32,000 tonnes of Pb remain stored in
formerly mined tributaries, with a further 123,000 tonnes stored in the Swale floodplain.
Combined storage represents more than half of the total Pb that is likely to have been
released during mining operations, suggesting that the impacts of metal mining are
extremely long-lasting. Concentrations of Pb, Zn and Cd in tributary, floodplain and flood
sediments greatly exceed current U.K. environmental quality guidelines and catchment specific
background values. Metal enrichment as a result of historical mining operations
could therefore pose a serious and long-term threat to plant and animal health in the Swale