Authors: Bowell, RJ

Open access courtesy of:


Cite As:
Bowell, RJ 2023, 'Natural attenuation in the vadose zone: Nature’s gift to mine closure', in B Abbasi, J Parshley, A Fourie & M Tibbett (eds), Mine Closure 2023: Proceedings of the 16th International Conference on Mine Closure, Australian Centre for Geomechanics, Perth,

Download citation as:   ris   bibtex   endnote   text   Zotero

Natural geochemical attenuation in the vadose zone refers to the process by which chemical parameters are naturally degraded, transformed, or immobilized as they migrate through the unsaturated zone above the water table. The vadose zone that often underlies mine waste facilities is a chemical active environment that involves physical, biological, and chemical interactions. These processes can effectively reduce the concentrations and mobility of contaminants, leading to their eventual removal or degradation. Here are some key natural attenuation processes that can occur in the vadose zone: Biodegradation: Microorganisms present in the soil can metabolize certain chemicals such as ammonia, cyanide or nitrates, breaking them down into simpler and less toxic compounds. Sorption and adsorption are processes by which chemical parameters can be chemically or physically trapped or bound to soil particles through the mechanisms of sorption or adsorption. This can reduce their mobility and availability for further transport. These processes are a function of the pH and redox of the environment, minerals present in the soil and prevailing water chemistry. Volatilization can also occur within the vadose zone and is an important control on the removal of parameters such as cyanide and ammonia. In addition, other chemical reactions may occur involving oxidation-reduction reactions, hydrolysis, and photolysis that can lead to precipitation or incorporation of chemical parameters into non-soluble mineral forms. In addition, although not often spoken about dilution by lower concentration waters in the vadose zone, can reduce or mitigate groundwater impacts. The effectiveness of natural attenuation in the vadose zone depends on several factors, including the nature of the chemicals, the redox and pH potential of the environment, soil properties, groundwater flow rates, and site-specific conditions, such as the availability of oxygen, nutrients, and suitable microbial populations. Such processes can occur in a wide variety of environments. Natural attenuation is an important aspect in long-term management of chemical loading in the environment and whilst it has limitations, combined with other methods such processes are effective in mine closure and should be considered in the planning and assessment of long-term geochemistry in post closure facilities.

Keywords: Natural Attenuation, Mine Closure, Geochemistry

Akcil A & Mudder T 2003. Microbial destruction of cyanide wastes in gold mining: process review Biotechnology Letters, 25, pages 445–450
Bannister A, Brabham P, Jones T, Bowell R 2018: Performance and Review of Passive Minewater Treatment Sites, Pelenna Valley, Wales. – In: Wolkersdorfer, Ch.; Sartz, L.; Weber, A.; Burgess, J. & Tremblay, G.: Mine Water – Risk to Opportunity (Vol I). – p. 84 – 91; Pretoria, South Africa (Tshwane University of Technology).
Beane RE & Titley, SR 1981 Porphyry Copper Deposits: Part II. Hydrothermal Alteration and Mineralization. Economic Geology, 75, 235-269
Berger AC, Bethke CM,& Krumhansl JL 2000 A process model of natural attenuation in drainage from a historic mining istrict. Appl Geochem 15:655–666
Bhatti, TM, Bigham, JM, Vuorinen, A & Tuovinen,OH 1994 Alteration of mica and feldspars associated with the microbiological oxidation of pyrrhotite and pyrite. In: Alpers, CN & Blowes, DW (eds) Environmental Geochemistry of Sulfide Oxidation. ACS Symposium, Series 550, 90-107.
Bigham, JM 1994 Mineralogy of ochre deposits. In: JL Jambor & DW Blowes, (eds), Environmental Geochemistry of Sulfide Mine Waste,. 103-131. Mineralogical Association of Canada.
Blowes DW, Ptacek CJ 1994 Acid–neutralization mechanisms in inactive mine tailings. In: Blowes DW, Jambor JL (eds). The Environmental Geochemistry of Sulfide Mine Wastes, Mineralogical Assoc of Canada, pp 271–292
Botz M, Mudder T 2000 Modelling of natural cyanide attenuation in tailings impoundments. Min. Metall. Proces. 17: 228–233
Bowell, R.J. 1994 Arsenic sorption by Iron oxyhydroxides and oxides. Applied Geochemistry, 9., 279-286.
Bowell RJ 2014 Hydrogeochemistry of the Tsumeb Deposit: Implications for Arsenate Mineral Stability. Reviews in Mineralogy and Geochemistry, volume 79, 589-630
Bowell RJ, Craw D 2014 The management of Arsenic in the Mining Industry. Reviews in Mineralogy and Geochemistry, volume 79,507-532
Bowell, RJ, McCelland, G, Parshley, JV, Upton, B and Zhan, J 2009 Geochemical evaluation of heap rinsing of the gold acres heap, Cortez joint venture, Nevada. Minerals Engineering, 22, 477-489
Bowell, RJ, Declercq, J, Warrender, R, Prestia, A, Parshley, J, & Barber, J 2017. Geochemical Prediction of Arsenic Attenuation from Infiltrated Heap Leach Drainage, Daisy Mine, Nevada. Geochemistry, Exploration, Environment, Analysis
Bowell RJ, Donkervoort L, Griffiths R, Bailey AS, Clarkson B & Prestia A 2020 Adsorption of Arsenic, and Other Elements in Alluvium: Implications for Exploration and Environmental Geochemistry in the Great Basin. In: Vision for Discovery. Proceedings GSN Symposium, Reno, Nevada. May 2020.
Breithaupt, A 1863 Berg.- und hüttenmännisches Zeitung, Freiberg, Leipzig (merged into Glückauf): 22: 36
Chapman BM, Jones DR, Jung RF 1983 Processes controlling metal ion attenuation in acid mine drainage stream. Geochim Cosmochim Acta 47:1957–1973
Cox DP 1986, "Descriptive model of porphyry Cu," in Mineral Deposit Models, US Geological Survey, Bulletin 1693, p. 76, 79
Craw D, Bowell RJ 2014 The Characterization of Mine Waste. Reviews in Mineralogy and Geochemistry, volume 79,473-506
Dey, M, Bowell, RJ, Pooley, FD, & Williams, KP 2000 Chemical Stabilization of mine waste In: Waste Treatment and Environmental Impact in the Mining Industry MA Sánchez, F Vergara & SH Castro, (eds) University of Concepión, Santiago, Chile.
Đorđievski, S, Ishiyama, D, Ogawa, Y & Stevanovic, Z (2018) Mobility and natural attenuation of metals and arsenic in acidic waters of the drainage system of Timok River from Bor copper mines (Serbia) to Danube River. Environmental Science and Pollution Research, 25, 25005–25019.
Druzbicka, J, & Craw, D 2015. Metalloid Attenuation from Runoff Waters at an Historic Orogenic Gold Mine, New Zealand. Mine Water Environ 34, 417–429
Dzombak D, Morel F 1991 Surface Complexation Modeling: Hydrous Ferric Oxide. J Wiley&Sons, 400p.
Flores AN & Sola FM 2010 Evaluation of Metal Attenuaiton from Mine Tailings in SE Spain. Mine water Environ, 29, 53-67.
Gandy CJ, Smith JWN, & Jarvis AP 2007 Attenuation of mining-derived pollutants in the hyporheic zone: A review. Sci, Total Environ, 373, 435-446.
Johnson DB, & Hallberg KB 2003 The microbiology of acidic mine waters. Research in Microbiology, 154, 466-473.
Jones, JB, Fisher, SG, & Grimm, NB 1995. Nitrification in the hyporheic zone of a desert stream ecosystem. Journal of the North American Benthological Society 14(2). 249-258
Kimball, BA, Broshears, RE, Bencala, KE & McKnight, DM 1994. Coupling of hydrologic transport and chemical reactions in a stream affected by acid mine drainage. Environmental Science & Technology, 28. 2065-2073
Kwong, YTJ & Ferguson, KD 1997 Mineralogical changes during NP determinations and their implications. In: Proceedings ICARD’97, Vancouver. 435-447
Lawrence, RW & Wang, Y 1997 Determination of Neutralization in the prediction of acid rock drainage. In: Proceedings ICARD’97, Vancouver. 451-464.
Markwiese JT, Rogers WJ, Carriker NE, Thal DI, Vitale RJ, Gruzalski JG, Rodgers EE &, Babyak CM, Ryti RT. 2014 Natural attenuation of coal combustion waste in river sedimentsEnviron Monit Assess. 186(8):5235-46.
Moncur MC, Ptacek CJ, Blowes DW, & Jambor JL 2005 Release, transport and attenuation of metals from an old tailings impoundment. Applied Geochemistry, 20, 639-659.
Morse, JW, 1983 The kinetics of calcium carbonate dissolution and precipitation. In: Reeder, R.J., ed., Reviews in Mineralogy. Mineralogical Society of America, 11, 227-264.
Mudder T, Botz M, Smith A 2001 The Chemistry and Treatment of Cyanidation Wastes, 2nd edn. Published by Mining Journal Books Limited, London UK
Nesbitt, HW and Jambor, JL 2008. Role of mafic minerals in neutralizing ARD, demonstrated using a chemical weathering methodology. In: L.J Cabri and DJ. Vaughan (eds) Modern Approaches to Ore and Environmental Mineralogy. Mineralogical Association of Canada Short Course Volume 27, pp403-421
Nordstrom, DK & Alpers, CN 1999 Geochemistry of Acid Mine Waters. In: Plumlee, G.S. and Logsdon, M.J., eds., The Environmental Geochemistry of Mineral Deposits. Rev.Econ.Geol, 6A. Soc. Econ.Geol. Inc., Littleton, CO. 133-160
Povarennykh AS, & Rusakova LD 1973 Kafehydrocyanite (K4[Fe(CN)6] · H2O) a cyanide mineral from the Medvezhii Log Au deposit: Geol.Zhurn, 33/2, 24-30[in Russian]
Raybuck SA 1992 Microbes and microbial enzymes for cyanide degradation. Biodegradation 3: 3–18.
Rose AW 2010 Advances in passive treatment of coal mine drainage 1998–2009. In: Proceedings of the 27th ASMR, Pittsburgh, PA, pp 847–887
. Sidenko, N Cooper, MA Sherriff BL, & Jamieson HE 2009 Formation and stability of (Na,K)2Zn3[Fe(CN)6]2•nH2O in gold heap-leach mine-waste. Canadian Mineralogist 47, 525-531
Skousen J, Zipper CE, Rose AW, Ziemkiewicz PF, Nairn R, McDonald LM, & Kleinmann RL 2017 Review of Passive Systems for Acid Mine Drainage Treatment. Mine Water and the Environment volume 36, pages133–15
Smith A, Mudder T 1991 The Chemistry and Treatment of Cyanidation Wastes, 1st edn. Published by Mining Journal Books Limited, London UK
Stumm, W, Morgan L 1992 Chemistry of the solid-water interface. New York: Wiley-Interface.
Sverdrup, H.U., 1990. The kinetics of base cation release due to chemical weathering: Lund University Press, Lund. 246p.
Walling, DE, Owens, PN, Carter, J, Leeks, GJL., Lewis, S, Meharg, AA & Wright, J 2003. Storage of sediment-associated nutrients and contaminants in river channel and floodplain systems. Applied Geochemistry, 18(2). 195-220
Zagury GJ, Oudjehani K, & Deschenes L 2004 Characterization and availability of cyanide in solid mine tailings from gold extraction plants. Sci. Total Environment, 430, 211-224.

© Copyright 2024, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
View copyright/legal information
Please direct any queries or error reports to