Residual Contamination and Environmental Effects at the Former Vanda Station, Wright Valley, Antarctica. Peter Kevin Taylor Submitted in partial fulfilment for the degree of Master of Water Resource Management Waterways Centre for Freshwater Management, University of Canterbury, New Zealand 2015 Peter Taylor - Master of Water Resource Management Thesis Abstract Antarctica is regarded as a pristine environment, free from anthropogenic impacts. However, environmental contamination in areas of human occupation has occurred and can persist long after occupation ceases. Residual contamination of the land on which the former Vanda Station was built, remained following the stations decommissioning and site remediation in 1994. Since then the level of Lake Vanda has risen flooding most of the contaminated site. A re-evaluation was carried out to determine whether the flooding had allowed contaminants to enter the lake itself. Contamination was not found in the water column of Lake Vanda above the now flooded soils where contaminants had previously been found. Concentrations of trace elements, nutrients and organic compounds measured in the water were all within the natural concentration range in Lake Vanda. Observations of benthic cyanobacteria in affected and control sites indicated slightly enhanced growth at affected sites. Phosphate fertilisation may be contributing to this luxurious growth, and there appears to be no inhibition due to toxic trace elements. This study identified two fuel spills on the remaining unflooded land near the footprint of the former station. These soils contained elevated total petroleum hydrocarbons (TPH 2400-8900mg/kg), and the trace metals Pb (max 98.16 mg/kg) and Zn (max 158.16 mg/kg). These metal concentrations exceed ANZECC sediment guideline values and TPH exceeds the lowest observed effect concentration for Antarctic mosses. Toxicity characteristic leaching procedure (TCLP) results indicate the potential for Pb and Zn leaching from these soils in both acidic and neutral pH waters. While similar levels of contamination were found in Vanda Station soils in 1993 and 1997, and have not resulted in obvious adverse effects, the remediation of former work sites in Antarctica is required under The Madrid Protocol. The opportunity for minor remediation of these exposed soils, and the collection of litter and painted rocks exists. This process is recommended to remove sources of contaminants to Lake Vanda permanently in keeping with The Madrid Protocol. Peter Taylor - Master of Water Resource Management Thesis Acknowledgements Many people have helped me throughout the past two years to get me to this point. I would like to thank Joshua Gibson for assisting me in building sampling equipment, Scott Base for logistical support in Antarctica, Neil Foley for field assistance and NIWA for facilitating the return of samples to New Zealand. Thank you to Hill Laboratories, Cawthron Institute, the UC Chemistry Department, John Revell and Emma MacKenzie for sample analysis and assistance with analysis. Thank you to all the Waterways students who I have annoyed for help or information, or just an excuse to have a beer for lunch. Very big thank you to Suellen Knopick, your infectious laugh makes every day in the Waterways office a great day to be working. You are an absolutely amazing person for us students to have around! Thank you to Dr Ed Butler at Antarctica New Zealand and the Waterways Centre for funding, without money this would have been, well, impossible. Special thank you to Vanessa Gopperth for proofreading my work, not throwing too many staplers at me, and being a great help in all matters ! You are a literal rock star! Thank you to my mum and dad for helping and putting up with me over the past two years, and to Bailey for not being annoyed when I’m tired, grumpy, or just talking endlessly about university. And finally, thank you to my thre e supervisors. Jenny Webster -Brown, Sally Gaw, and Ian Hawes, you three have been an invaluable source of help and information, sorry for annoying you so much! Peter Taylor - Master of Water Resource Management Thesis Table of Contents List of Figures ........................................................................................................................................... I List of Tables .......................................................................................................................................... IV Abbreviations ......................................................................................................................................... V Chapter 1 - Introduction ......................................................................................................................... 1 1.1 Human Presence in Antarctica ..................................................................................................... 1 1.2 The Antarctic Treaty System ........................................................................................................ 2 1.3 Environmental Pressures and Effects ........................................................................................... 3 1.4 Lake Vanda ................................................................................................................................... 6 1.4.1 Microbial Communities ......................................................................................................... 8 1.5 Vanda Station - A New Zealand Outpost ...................................................................................... 9 1.5.1 Environmental Management at Vanda Station ................................................................... 11 1.5.2 Survey Results of Past Leaders ............................................................................................ 13 1.5.3 Decommissioning, AEE and Remediation at Vanda Station ................................................ 15 1.6 Residual contamination at the former Vanda Station Site ........................................................ 17 1.6.1 Trace Element Contamination ............................................................................................. 18 1.6.2 Hydrocarbon Contamination ............................................................................................... 19 1.6.3 Nutrient Contamination ...................................................................................................... 20 1.6.4 Release of contaminants ..................................................................................................... 21 1.7 Rational for This Study ............................................................................................................... 21 1.7.1 Study Objectives .................................................................................................................. 22 Chapter 2 - Methods ............................................................................................................................ 23 2.1 Site Locations.............................................................................................................................. 25 2.1.1 Flooded Sites ....................................................................................................................... 25 2.1.2 Dry sites ............................................................................................................................... 26 2.2 Sampling ..................................................................................................................................... 28 2.2.1 Flooded Sites ....................................................................................................................... 28 2.2.2 Dry Sites ............................................................................................................................... 33 2.3 Sample Analysis .......................................................................................................................... 34 Peter Taylor - Master of Water Resource Management Thesis 2.3.1 Trace Elements and Major Cations ..................................................................................... 34 2.3.2 Total Organic Carbon ........................................................................................................... 36 2.3.3 Volatile Organic Compounds ............................................................................................... 36 2.3.4 Hydrogen sulphide .............................................................................................................. 37 2.3.5 Major anions ........................................................................................................................ 37 2.3.6 Nutrients .............................................................................................................................. 39 2.3.7 Total Petroleum Hydrocarbons and PAH’s .......................................................................... 40 2.3.8 TCLP Leach Testing .............................................................................................................. 40 2.5 Errors and Omissions .................................................................................................................. 41 2.5.1 Difficulties in working in Antarctica .................................................................................... 42 Chapter 3 - Results ............................................................................................................................... 43 3.1 Lake Waters ................................................................................................................................ 43 3.1.1 Site Descriptions .................................................................................................................. 43 3.1.2 Major Ion chemistry of Lake Water ..................................................................................... 47 3.1.3 General Water Quality Parameters ..................................................................................... 49 3.1.4 Trace Elements .................................................................................................................... 55 3.1.5 Sulphide ............................................................................................................................... 61 3.1.6 Nutrients .............................................................................................................................. 61 3.1.7 Volatile Organic Compounds ............................................................................................... 63 3.1.8 Total Organic Carbon ........................................................................................................... 64 3.2 Cyanobacterial Observations ..................................................................................................... 65 3.3 Soils and Sediments .................................................................................................................... 67 3.3.1 Physical Contaminants and Site Descriptions ..................................................................... 67 3.3.2 Trace Element Contaminants .............................................................................................. 69 3.3.3 Hydrocarbon Contaminants ................................................................................................ 73 3.3.4 TCLP leaching ....................................................................................................................... 75 Chapter 4 - Discussion .......................................................................................................................... 77 4.1 Residual Contamination in Flooded Sites ................................................................................... 77 4.1.1 Trace Elements .................................................................................................................... 78 4.1.2 Nutrients .............................................................................................................................. 81 4.1.3 Hydrocarbons ...................................................................................................................... 82 Peter Taylor - Master of Water Resource Management Thesis 4.1.4 Organic Carbon and Dissolved Oxygen ............................................................................... 83 4.1.5 Observed Ecosystem Effects ............................................................................................... 83 4.2 Residual contamination on Dry Soils .......................................................................................... 85 4.2.1 Trace elements .................................................................................................................... 85 4.2.2 Hydrocarbons ...................................................................................................................... 87 4.2.3 Physical debris ..................................................................................................................... 88 4.3 Vulnerability of Lake Vanda to Environmental Change .............................................................. 88 4.3.1 Potential for Contaminant Release from Soils .................................................................... 90 4.4 Is further remediation necessary? ............................................................................................. 92 Chapter 5 - Conclusions and Recommendations ................................................................................. 94 5.1 Recommendations ..................................................................................................................... 95 References ............................................................................................................................................ 96 Appendix 1 - Major Ion Chemistry ..................................................................................................... 101 Appendix 2 - Water trace elements ................................................................................................... 103 Appendix 3 - Nutrients ....................................................................................................................... 105 Appendix 4 - Hydrocarbons ................................................................................................................ 106 List of VOCs analysed ..................................................................................................................... 106 List of PAHs analysed ...................................................................................................................... 107 Appendix 5 - TCLP Results .................................................................................................................. 108 Peter Taylor - Master of Water Resource Management Thesis List of Figures Figure 1 - Ross Sea region and McMurdo Dry Valleys. Inset: Ross Sea Region in relation to Antarctica (USGS, 2010). .......................................................................................................................................... 5 Figure 2 - Wright Valley, McMurdo Dry Valleys. The former Vanda Station was located at eastern end of Lake Vanda (arrow). .................................................................................................................... 6 Figure 3 - Lake Vanda level rise since 1968 relative to Astro “A” survey point. Data series 1968 -1989 (Chinn, 1993), 1990-2014 (McMLTER, 2015). The two arrows refer to the commissioning and decommissioning of the station. ............................................................................................................ 8 Figure 4 - Vanda Station in 1990/1991 season looking west towards the Asgard Ranges. Photo credit Paul Brody. ........................................................................................................................................... 11 Figure 5 - Locations of spills and disposed contaminants at Vanda Station (sites A-M) as identified by survey responses (Sheppard et al., 1994). Sites referred to in the following section are A-M in this figure. ................................................................................................................................................... 13 Figure 6 - Refuelling drum at the former Vanda Station. Note the lack of fuel bund or any spill containment measures (Harrowfield, 1999). ....................................................................................... 14 Figure 7 - Sampling map from Webster et al (2003) for the former Vanda Station site and Greywater Gully. Note that control sites are not within this frame. ..................................................................... 18 Figure 8 - Comparison of sampling locations at the former station and Greywater Gully in this study (red) and from Webster et al (2003) (black). Modified from Webster et al (2003), depth determined maps drawn prior to flooding. Thick black lines indicate present (Dec-2014) shoreline. .................... 23 Figure 9 - Lake Vanda, Vanda Station and environs looking South West, circa 1980. Photo Kim Westerskov. (Antarctica NZ, 2015) ....................................................................................................... 24 Figure 10 - Ariel view of the location of the former Vanda Station (larger island) looking west along the lake. Sampling locations are shown approximately for perspective only. Arrow indicates North (Photo taken 6/12/2015 by author). .................................................................................................... 24 Figure 11 - Sampling area on Lake Vanda showing all flooded sampling locations (red) and soil sampling location (blue) and GPS coordinates. Map created by walking the shoreline with a GPS in 2013/2014 season (Ian Hawes), sampling points taken during field work for this study ................... 27 Figure 12 - Generalised profile of GW, HP5, CG and VBG sampling sites where A-C are water sampling depths, D - pore water and sediment sampling location, E - thickness of ice, F - depth of water (piezometric level). .................................................................................................................... 32 Figure 13 - Sample collection and field measurements. Samples were drawn through water sampler via suction pump and sub sampled. ..................................................................................................... 32 Figure 14 - Close up of Greywater Gully as taken from Figure 8. The black transect line relates to the profile in Figure 15. .............................................................................................................................. 44 I Peter Taylor - Master of Water Resource Management Thesis Figure 15 - Depth profile of Greywater Gully from A-B (Figure 14). Black line (triangles) represents the lake bed; the blue lines represent the top and base of the ice cap. Points from left to right are: GW6, GW5, GW4, GW3, GW2, GW0. ................................................................................................... 44 Figure 16 - Greywater Gully looking west from a site north of GW3 towards GW4, GW5 and GW6. The island on the right is the location of the former Vanda Station. ................................................... 45 Figure 17 - Recent inundation of the former main helicopter pad and location of sampling points HP20, HP21 and HP23. ......................................................................................................................... 46 Figure 18 - Orange painted rock at the edge of Lake Vanda in the vicinity of HP21 ........................... 46 Figure 19 - Ternary diagram showing major cation (left) and anion (right) chemistry in all water samples from Lake Vanda based on % of total molar concentrations. ................................................ 48 - - Figure 20 - Anionic molar concentration ratio between HCO3 and Cl showing the increasing - dominance of Cl with depth in the water column. .............................................................................. 48 Figure 21 - Temperature, DO, conductivity and pH profile for HP5 as measured on water samples collected at different depths. The ice cap occupies the first 2.2m of the profile. ............................... 50 Figure 22 - Temperature, DO, conductivity and pH profiles for CG and VBG as measured on water samples collected at different depths. Ice cap occupies the first 2.1-2.2m of the each profile. ......... 51 Figure 23 - Temperature, DO, pH and conductivity results for surface waters in Greywater Gully as taken on water samples collected at different depths. The ice cap occupies the first 1.5-2.0m of each profile. .................................................................................................................................................. 52 Figure 24 - Conductivity and pH profiles as measured using the CDT scanner. Note that measurements started at the base of the ice layer, not in the access hole drilled through the ice cap. .............................................................................................................................................................. 54 Figure 25 - Iron concentrations in Greywater Gully, HP and control sites showing dissolved (f) and total (uf) concentrations. ..................................................................................................................... 57 Figure 26 - Trace elements in Greywater Gully water and porewater samples showing dissolved (f) and total (uf) concentrations and the ANZECC 99%trigger value. ....................................................... 58 Figure 27 - Trace elements in HP water and porewater samples showing dissolved (f) and total (uf) concentrations and the ANZECC 99% trigger value ............................................................................. 59 Figure 28 - Trace elements in control sites, water and porewater samples, showing dissolved (f) and total (uf) concentrations. ..................................................................................................................... 60 Figure 29 - DRP and NOx-N concentrations for all water samples. ...................................................... 62 Figure 30 - Cyanobacterial mat growing on sediment on the edge of HP21, photographed area approximately 30cm x 30cm . .............................................................................................................. 65 Figure 31 - Underwater camera observations of cyanobacterial mat growth at GW0 (a), GW4 (b), GW5 (c) and VBG (d). ........................................................................................................................... 66 Figure 32 - Battery found in the soil near site HP23. ........................................................................... 67 II Peter Taylor - Master of Water Resource Management Thesis Figure 33 - Discolouration of the soil at site HP20. This site smelled strongly of hydrocarbons. ........ 68 Figure 34 - Lead and zinc concentrations in the soil profile from HP10. ............................................. 71 Figure 35 - Pb and Zn concentrations in the soil profile from HP20. ................................................... 71 Figure 36 - Relationship between trace element concentrations and Fe% in the soil matrix ............. 72 Figure 37 - Fuel contamination in the soil profile of HP10.................................................................. 74 Figure 38 - Fuel contamination in the soil profile of HP20.................................................................. 74 Figure 39 - Leachate concentrations of Ni, Fe, Cr and Co from dry soil samples. ................................ 75 Figure 40 - Leachate concentrations of Mn, Pb, As, Cd, Zn and Cu from dry soil samples. ................. 76 III Peter Taylor - Master of Water Resource Management Thesis List of Tables Table 1 - Sample collection and preservation depending on type of analysis. .................................... 29 Table 2 - Flooded sampling sites located within Greywater Gully. Included are the sample depths below ice surface, depth of porewater and sediments below lake bed, and thickness of ice ............ 30 Table 3 - All other flooded sampling sites located outside of Greywater Gully. Included are the sample depths below ice surface, depth of porewater and sediments below lake bed, and thickness of ice. .................................................................................................................................................... 31 Table 4 - Soils from dry sample sites, including depth of sample, location and date of sampling ...... 33 Table 5 - QC data showing ICP-MS recovery of IV SRM 1643 standard reference material. Included are detection limits, trace element recovery in acid blanks and digest blanks ................................... 36 Table 6 - QC data for major anion data including blanks, duplicate variances and standard reference variances. .............................................................................................................................................. 38 - Table 7 - QC data for the analysis of HCO3 . Four standards and one blank were included in the th th sample run and were analysed after the 10 and 20 sample. ........................................................... 39 Table 8 - QA/QC data for trace element analysis on TCLP leachates. .................................................. 41 Table 9 - Major ion chemistry in lake and porewaters in Lake Vanda. Displayed are the average concentrations (mg/L) for all sites excluding VBG at each depth. ....................................................... 48 Table 10 - pH, conductivity, and DO in pore water samples taken from Greywater Gully sites. Samples depth is metres below lake bed. ............................................................................................ 50 Table 11 - pH, conductivity, temperature and DO results from HP sites. ............................................ 50 Table 12 - pH, conductivity, temperature and DO results the OS control site. ................................... 51 Table 13 - Maximum total concentrations (µg/L) of trace elements measured in each water profile (i.e. 3 depths and porewater sample). Included are the 95% and 99% ANZECC trigger values .......... 55 Table 14 - VOC results for basal water samples. .................................................................................. 63 Table 15 - VOC results for porewater samples ..................................................................................... 64 Table 16 - TOC results for basal water samples. .................................................................................. 64 Table 17 - Trace element results in sediment and soil samples as determined from acid digestion. Highlighted results indicate that the concentration is 1.25x (green) and 1.5x (blue) the relevant control site. All results in mg/kg. .......................................................................................................... 70 Table 18 - Total Petroleum Hydrocarbon results for sediment and soil samples, results in mg/kg ... 73 Table 19 - Maximum dissolved concentrations of trace elements in Greywater Gully SPF results from Webster et al (2003) and porewater samples in this study. ................................................................ 80 IV