Assessment of Diffuse Pollution Originating from Estuarine Historical Landfills O’Shea, Francis Timothy
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Assessment of diffuse pollution originating from estuarine historical landfills O’Shea, Francis Timothy The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author For additional information about this publication click this link. http://qmro.qmul.ac.uk/xmlui/handle/123456789/12995 Information about this research object was correct at the time of download; we occasionally make corrections to records, please therefore check the published record when citing. For more information contact [email protected] Assessment of diffuse pollution originating from estuarine historical landfills Francis Timothy O’Shea A thesis submitted in partial fulfilment of the requirements of the degree of Doctor of Philosophy. School of Geography, Queen Mary, University of London 2016 I, Francis Timothy O’Shea, confirm that the research included within this thesis is my own work or that where it has been carried out in collaboration with, or supported by others, that this is duly acknowledged below and my contribution indicated. Previously published material is also acknowledged below. I attest that I have exercised reasonable care to ensure that the work is original, and does not to the best of my knowledge break any UK law, infringe any third party’s copyright or other Intellectual Property Right, or contain any confidential material. I accept that the College has the right to use plagiarism detection software to check the electronic version of the thesis. I confirm that this thesis has not been previously submitted for the award of a degree by this or any other university. The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author. Signature: Date: Details of collaborations: Michelle Morris, Queen Mary University of London, performed Mercury analysis at the Biotron Centre for Climate Change, University of Western Ontario, Canada, during April 2014. The raw data is presented within Section 4.4.2, data analysis and interpretation was undertaken by myself. Professor Andrew Cundy, University of Brighton, performed 210Pb and 137Cs gamma spectrophotometry on 17 sediment samples. These data are presented in Section 4.4.2. All interpretation was undertaken by myself. This work was supported by a Natural Environment Research Council CASE studentship in association with Arcadis N.V. (Grant number NE/I018212/1). 2 Acknowledgements Firstly, I would like to thank my supervisors, Dr. Kate Spencer, Professor James Brasington, Mark Webb and Katy Baker for their support, inspiration, understanding and general willingness to work with me for the last 3(+) years! I owe you all a lot! I am also indebted to past and present laboratory staff at QMUL; Simon Dobinson, Michelle Day, Laura Cox, Kate Peel, Natalie Ludgate and Maggie Fitzherbert, to name but a few. It has been a pleasure working with you all, and thank you for your patience over the last few years! Thanks also go to Dr. Emma Shuttleworth, Niall Lehane, Professor Andrew Cundy and Professor Andy Plater. You have all played key roles in the last few years, through either scientific discussion, method explanations, sample analysis or equipment loan. In addition, I am thankful to Dr. James Rothwell for my initial introduction into contaminant geochemistry, Ray Howarth for your enthusiasm towards physical geography, and to examiners Dr. Neil Rose and Dr. Mark Scrimshaw. To everyone from 224, Kieran Stanley, Michelle Morris, Eleanor Webster, James Holloway, Joe James, and further afield in 104, John Groves, Cianna Wyshnytzky, James Brand, Anna March, Ginny Benardout and Harold Lovell. I have made some incredible friends over the past few years, with whom I have shared a lot of stories, experiences, coffees and beers. You have made this process even more enjoyable! Finally, I would like to thank my mum, Shelagh, and my brother, Tom, for their support throughout the PhD process, and of course Anna Glover, for your unconditional and often well timed encouragement, without whom I would not have been so happy and well fed! Thank you. 3 Abstract The UK contains 5000 unlined historical landfills in the coastal zone currently at risk of erosion within the next 50 years. These rely on natural attenuation in surrounding sediment to reduce the contaminant load to the environment. This thesis investigates the extent and magnitude of sediment metal contamination from historical estuarine landfills. An intensive investigation of Newlands historical landfill, Essex, indicated elevated metal concentrations in surface and sub-surface sediments. Surface sediment concentrations were similar to other industrially impacted estuaries, whilst peak metal concentrations at c. 50 cm depth were indicative of industrial activity in the mid-20th Century. Below this depth, sediments were enriched with Pb (EF > 2) and Zn (EF = 1.5) indicative of an historic leachate plume that extends c. 15 m from the landfill site boundary. These sediments present a secondary source of diffuse pollution and a site contamination load of c. 1200 kg Pb. In-situ XRF was demonstrated as a rapid contamination screening tool for Fe, Pb, Sr and Zn enabling a broad-scale investigation of historical landfills across SE England. Sediment cores from eight sites containing both hazardous and inert waste were screened. Concentrations and EFs of Pb and Zn at depth were significantly higher in hazardous sites compared to inert sites. Spatial distributions of Pb and Zn were comparable to Newlands historical landfill. This indicates that diffuse pollution from historical landfill sites with similar chemical and physical attributes to Newlands is likely to present a regional, if not national problem, with UK historical landfills presenting contaminated sediments, comprising a significant, previously unidentified and unquantified diffuse pollution source in the coastal zone. 4 Contents Acknowledgements ........................................................................................................... 3 Abstract ............................................................................................................................. 4 Contents ............................................................................................................................ 5 List of Figures .................................................................................................................... 9 List of Tables ................................................................................................................... 12 List of Equations .............................................................................................................. 15 List of Appendices ........................................................................................................... 16 Chapter 1 Introduction ............................................................................................... 17 Chapter 2 Thesis Outline ........................................................................................... 20 Chapter 3 Literature Review ...................................................................................... 21 3.1. Landfilling .......................................................................................................... 21 3.1.1. Landfill Design ........................................................................................... 21 3.1.2. Leachate Composition and Generation ...................................................... 24 Controls on Leachate Composition ....................................................................... 24 Leachate Generation ............................................................................................ 27 3.2. The Estuarine Environment ............................................................................... 28 3.2.1. The Thames Estuary .................................................................................. 30 3.2.2. Coastal Erosion in the Thames and South East ......................................... 32 3.3. Metals in the Estuarine Environment ................................................................. 33 3.3.1. Processes Affecting Mobility ...................................................................... 35 3.3.2. Bioavailability ............................................................................................. 38 3.4. Approaches to Contaminated Land Risk Assessment ....................................... 40 3.5. Legal Context of Historical Coastal Landfills ...................................................... 43 3.6. Conclusion ........................................................................................................ 45 Chapter 4 Metal Distribution in Sediments Adjacent to an Historical Landfill. .............. 46 Abstract ....................................................................................................................... 46 4.1. Introduction ....................................................................................................... 47 4.2. Research Site ................................................................................................... 49 4.3. Methods ............................................................................................................ 51 4.3.1. Field Methodology .....................................................................................