Alice Springs SAT Project Hydrological and Water Quality Monitoring Report 2008-2009 Konrad Miotli ński, Karen Barry, Peter Dillon and Marc Breton July 2010 This is a report of the NWC Raising National Water Standards project: Facilitating recycling of stormwater and reclaimed water via aquifers . Water for a Healthy Country Flagship Report series ISSN: 1835-095X Australia is founding its future on science and innovation. Its national science agency, CSIRO, is a powerhouse of ideas, technologies and skills. CSIRO initiated the National Research Flagships to address Australia’s major research challenges and opportunities. They apply large scale, long term, multidisciplinary science and aim for widespread adoption of solutions. The Flagship Collaboration Fund supports the best and brightest researchers to address these complex challenges through partnerships between CSIRO, universities, research agencies and industry. The Water for a Healthy Country Flagship aims to provide Australia with solutions for water resource management, creating economic gains of $3 billion per annum by 2030, while protecting or restoring our major water ecosystems. The work contained in this report is collaboration between CSIRO and Power and Water Corporation. For more information about Water for a Healthy Country Flagship or the National Research Flagship Initiative visit www.csiro.au/org/HealthyCountry.html Citation: Miotli ński et al., 2010. Alice Springs SAT Project Hydrological and Water Quality Monitoring Report 2008-2009. CSIRO: Water for a Healthy Country National Research Flagship Authors: Konrad Miotlinski, Karen Barry and Peter Dillon work with CSIRO Land and Water at the Waite Campus in Adelaide, and undertook this work within the Water Recycling and Diversified Supplies Stream of Water for a Healthy Country’s Urban Water Theme. [email protected] Marc Breton works with PowerWater Corporation and is based in Darwin/Alice Springs. Copyright and Disclaimer © 2010 CSIRO To the extent permitted by law, all rights are reserved and no part of this publication covered by copyright may be reproduced or copied in any form or by any means except with the written permission of CSIRO. Important Disclaimer: CSIRO advises that the information contained in this publication comprises general statements based on scientific research. The reader is advised and needs to be aware that such information may be incomplete or unable to be used in any specific situation. No reliance or actions must therefore be made on that information without seeking prior expert professional, scientific and technical advice. To the extent permitted by law, CSIRO (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this publication (in part or in whole) and any information or material contained in it. Cover Photograph: Description: Recharge Basin 1 in the Alice Springs SAT Trial site Photographer: Karen Barry © 2010 CSIRO CONTENTS Acknowledgements ....................................................................................................v Executive Summary...................................................................................................vi 1. Introduction........................................................................................................1 1.1. Soil Aquifer Treatment .............................................................................................. 1 1.2. Alice Springs SAT operation..................................................................................... 2 2. Geological setting..............................................................................................4 2.1. General geology and hydrogeology.......................................................................... 4 2.2. Local setting at the AZRI site.................................................................................... 6 2.2.1. Geology and hydrogeology....................................................................................6 2.2.2. Sediment geochemistry .........................................................................................7 2.2.3. Background groundwater chemistry ......................................................................7 2.2.4. Studies on clogging potential.................................................................................7 3. Methodology for site investigations.................................................................9 3.1. Site instrumentation and monitoring of water quantity and quality ........................... 9 3.2. Attenuation of contaminants and saturation index calculations.............................. 15 4. Infiltration rates................................................................................................16 4.1. Infiltration from the basins....................................................................................... 17 4.2. The effect of infiltration on the unsaturated zone ................................................... 19 4.3. The effect of infiltration on the saturated zone ....................................................... 21 4.4. The effects of infiltration under RB4 and RB2 (July 2009) ..................................... 25 4.5. Quality of source water ........................................................................................... 29 4.6. Influence of water quality on infiltration rates ......................................................... 33 5. Results concerning fate of constituents........................................................35 5.1. Nitrogen, carbon and phosphorus fate ................................................................... 35 5.2. Salinity and ability to recover recharge water......................................................... 38 5.3. Tracers of recharged water in the aquifer............................................................... 40 5.4. Aeration of the profile and other field parameters .................................................. 40 5.5. Leaching of metal oxides from the profile............................................................... 43 5.6. Fate of trace organics ............................................................................................. 44 5.7. Biogeochemical processes during SAT operation.................................................. 44 6. Conclusions.....................................................................................................48 7. Recommendations...........................................................................................50 References ................................................................................................................52 Appendix A: Geological cross-sections..................................................................55 Appendix B: Statistical data on recharge water, ambient groundwater, unsaturated zone water, and saturated zone mixed water ...........................56 Appendix C: Water quality parameters monitored at the AZRI site* .....................58 Appendix D: Hydraulic loading, average daily infiltration and infiltration coefficient values calculated for individual wetting periods using the mass balance (equation 5) ..............................................................................60 Appendix E: Permeability of basins’ bottoms determined with disc permeameter using tap water (Roe Creek) ....................................................61 Alice Springs SAT project 2008-2009 Page i Appendix F: Inflow rates over duration of wetting, duration of drying, and turbidity ............................................................................................................62 Appendix G: Hydraulic heads in the shallow piezometers beneath RB2 and RB4 during the field campaign in July 2009 ..................................................63 Appendix H: Infiltration trial of the basins A and B (6x6 m) ..................................64 Appendix I: Concentration of inorganic nitrogen compounds from soil cores in July 2009 ......................................................................................................65 Appendix J: Pharmaceuticals and herbicides in recharge water ..........................66 LIST OF FIGURES Figure 1 Soil Aquifer Treatment System infiltrating water to an unconfined aquifer .. 1 Figure 2 Location of SAT site in the area of Alice Springs........................................ 3 Figure 3 Geological cross section of Quaternary deposits at the AZRI site. ............. 5 Figure 4 Hydrogeological sketch of the Outer Basin aquifer in the area of SAT site. 6 Figure 5 Location of the infiltration basins and the monitoring wells at the AZRI site. ................................................................................................................................ 9 Figure 6 Observation well RN17948, shallow piezometers, suction cups, tensiometers, soil water content sensors, dissolved oxygen and Eh sensors located in RB4.................................................................................................................... 10 Figure 7 Schematic representation of water sampling locations at AZRI site in and adjacent RB4 ......................................................................................................... 13 Figure 8 Measurement of hydraulic conductivity of RB2 using