Distribution and Speciation of Heavy Metals in Sediments from Lake Burragorang by Archana Saily Painuly A Thesis Presented for the Degree of Masters of Engineering (Honours) School of Engineering College of Health & Science University of Western Sydney 2006 1 Acknowledgments At last I got this moment to write my gratitude to all those who have directly or indirectly supported me to make my long cherished dream to come to a reality. At the outset, I express my profound sense of gratitude and respect to my chief supervisor Dr. Surendra Shrestha for his invaluable guidance and support academically as well as morally. Without his concrete suggestions it would have been impossible to bring out this work in the current form. Words are inadequate to express my heartfelt appreciation for Dr. Paul Hackney, my associate supervisor, who has been a constant help throughout this entire thesis. Special thanks to him to have helped me perform last stages of sampling during my third trimester. I take this opportunity to thank Prof. Steven Riley, Head School of Engineering for providing me the infrastructural facilities to carry out this work. I am grateful to Technical staff of School of Engineering for constructing glove box and extrusion device for processing sediment samples. I would also like to thank Professor Samuel Adeloju for arranging metal analysis in Australian Government Analytical Laboratories (Pymble, NSW). I am thankful to Dr. Honway Louie and Dr. Michael Wee and their staff at Australian Government Analytical Laboratories (Pymble, NSW) for performing metal analysis. My sincere thanks to Dr. Henk Heijnis, Jennifer Harrison and Atun Zawadzki, from Environmental Radiochemistry at Australian Nuclear Science and Technology Organisation (Sydney, NSW) for their assistance with the 210Pb dating technique, determination of age profiles and interpretation of the data. I would like to record my thanks to my work colleagues at Environmental Health Sharron, Sue, Burhan, Maree and Gavin for the moral support and encouragement. My thanks are due to Dr. Robert Mulley, Head of School Natural Sciences for approving my study leave. I shall remain indebted to Dr. Arun Garg and Dr.Vinita garg for their moral support and valuable advice. Countless images flash through my mind when I remember the hard phase of time I was passing through, and here my husband, Nirmal, deserve a special mention who made the most conspicuous contribution in making this ambition reality. I must also place on record my deep sense of love and tender sentiments for my family members for their perpetual encouragement and inspiration, despite being far away. I will fail in my duty if I forget to mention ‘my bundle of joys’ Goura and Shriya, who were born during this period. They kept me cheerful even when the things were going tough. 2 Statement of Authentication The work presented in this thesis is, to the best of my knowledge and belief, original except as acknowledged in the text. I hereby declare that I have not submitted this material, either in full or in part, for a degree at this or any other institution. …………………………………………… (Signature) 3 Table of Contents ABBREVIATIONS..................................................................9 ABSTRACT............................................................................10 CHAPTER I. INTRODUCTION ........................................12 1.1. BACKGROUND ..............................................................12 1.2. LAKE BURRAGORANG AND ITS CATCHMENT ...............14 1.3. REPORT ORGANISATION...............................................26 CHAPTER II. MATERIALS AND METHODS................28 2.1 FIELD SAMPLING.............................................................28 2.2 SEDIMENT GRAB .............................................................28 2.3 SEDIMENT CORE..............................................................31 2.4 ANALYTICAL METHODS..................................................33 2.4.1 MOISTURE CONTENT....................................................33 2.4.2 ORGANIC MATTER AND CARBONATE CONTENT ...........34 2.4.3 TOTAL NITROGEN AND PHOSPHORUS ..........................34 2.4.4 ACID EXTRACTABLE METAL........................................35 2.4.5 SPECIATION ..................................................................35 2.4.5.1 SEQUENTIAL EXTRACTION........................................35 2.4.5.2 SIMULTANEOUSLY EXTRACTED METAL (SEM) AND ACID VOLATILE SULPHIDE (AVS) ........................................36 2.4.6 SEDIMENTATION STUDY ..............................................39 2.4.7 STATISTICAL TREATMENT OF DATA ............................40 CHAPTER III. DISTRIBUTION OF METALS AND SPECIATION IN SEDIMENT OF LAKE BURRAGORANG USING SEQUENTIAL EXTRACTION .................................................................................................42 3.1 INTRODUCTION................................................................42 3.2 STUDY AREA...................................................................48 3.3 RESULTS AND DISCUSSION..............................................48 3.3.1 METAL DISTRIBUTION .................................................48 3.3.2 METAL SPECIATION .....................................................52 CHAPTER IV. DISTRIBUTION OF HEAVY METALS AND THEIR BIOAVAILABILITY USING SEM AND AVS IN THE SEDIMENTS OF LAKE BURRAGORANG .......61 4.1 INTRODUCTION................................................................61 4.2 STUDY AREA...................................................................63 4.3 RESULTS AND DISCUSSION..............................................64 4.3.1 ORGANIC MATTER AND CARBONATE CONTENT ...........64 4.3.2 NUTRIENTS...................................................................65 4.3.3 BACKGROUND AND METAL DATA ...............................66 4.3.4 METALS........................................................................69 4.3.5 ACID VOLATILE SULPHIDE AND SIMULTANEOUSLY EXTRACTED METALS ............................................................74 CHAPTER V. SEDIMENTARY RECORD OF HEAVY METAL POLLUTION OF LAKE BURRAGORANG USING 210PB DATING..........................................................78 5.1 INTRODUCTION................................................................78 5.2 LEAD –210 RADIOMETRIC DATING.................................79 5.3 MODELS FOR SEDIMENTATION RATE DETERMINATION..81 5.4 SAMPLING LOCATIONS....................................................81 5.5 SELECTION OF CORES......................................................82 5.6 RESULTS AND DISCUSSION..............................................82 5.6.1 CORE 1 (NEAR DAMWALL) ...........................................82 5.6.2 CORE 2 (NEAR COX RIVER) ..........................................83 5.6.3 CORE 3 (NEAR NATTAI RIVER).....................................83 CHAPTER VI. CONCLUSION ..........................................90 REFERENCES ......................................................................95 APPENDIX A.......................................................................114 APPENDIX B.......................................................................115 APPENDIX C.......................................................................119 APPENDIX D.......................................................................124 5 List of Tables Table 1.1. Warragamba catchment and its activities .......................................... 17 Table 2.1. Comparison of reference material values with obtained results....... 41 Table 3.1. Sediment quality guidelines for metals [Long et al., 1995]................ 49 Table 3.2. Metal distribution in the Lake Burragorang sediment grab samples according to sampling points............................................................ 50 Table-3.3. Percentage of total metal content among the different sediment chemical fractions determined by sequential extractions ............................ 53 Table 4.1. Lake Burragorang monitoring sites .................................................... 64 Table 4.2. Spatial and vertical distributions of carbonate content, organic matter and nutrients in sediment cores of Lake Burragorang .................... 67 Table 4.3. Variation in metal concentrations with depth in sediment core samples...................................................................................................... 71 Table 4.4. Background metal levels for Lake Burragorang from sedimentary metal concentrations ........................................................ 73 Table 4.5. Background metal levels for Lake Burragorang with other matrices ............................................................................................................................ 73 Table 4.6. Concentrations of AVS and SEM alongwith depth in sediments of Lake Burragorang ....................................................................................... 75 Table 4.7. Guidelines for determining metal toxicity to benthic organisms in freshwater sediments (values in mg/kg) [Grabowski, 2001] ........................ 76 Table 5.1. Activity variation of 210 Po, 226Ra and excess 210Pb with depth in sediment core 1................................................................................................. 86 Table 5.2. Activity variation of 210 Po, 226Ra and excess 210Pb with depth in sediment core 2................................................................................................. 86 Table 5.3. Activity variation of 210 Po, 226Ra and excess 210Pb