• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.34-44
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• 2021

Acid mine drainage (AMD) resulting from pyrite oxidation in mining areas, subsequently leads to soil acidification accompanied by lowering pH and high concentration of metals and metalloids in its surrounding environment. Regarding to this, the microbial amelioration has been considered as a promising option for a more cost-effective and eco-friendlier countermeasure, compared to the use of alkaline chemicals. This study was aimed to evaluate influencing factors in microbially-mediated amelioration of acidic soil spiked by simulated AMD. For this, microcosm experiments were conducted by acid-neutralizing bacterial consortium (dominated by Klebsiella sp. and Raoultella sp.) under the various conditions of AMD spikes (0-2,500 mg SO42-/L), together with acidic mine soil (0-100 g) or sphagnum peat (0-5 g) in the 200 mL of nutrient medium. The employed bacterial consortium, capable of resisting to high level of sulfate concentration (up to 1,500 mg SO42-/L) in low pH, generated the ammonium while concomitantly reduced the sulfate, subsequently contributing to the effective soil stabilization with an evolution of soil pH up to neutral. Furthermore, it demonstrates that suitable condition has to be tuned for successful microbial metabolism to facilitate with neutralization during practical application.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.107-111
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• 2004

This study was undertaken to summarize of the efficiencies of the passive treatment system and suggest future studies for the solution of mine drainage problem. Flow rates of mine drainage from the abandoned coal mines are about 80,000 ton/day. Contaminated mine drainages over about 50 ton/day of flow rate were treated by passive treatment facilities such as Successive Alkalinity Producing Systems(SAPS), oxidation pond and oxic wetland. Chemical analysis for 13 passive coal mine treatment facilities showed that SAPS was the core of treatment facilities because the variation of Fe removal rates was relatively smaller than any other processes and re-leaching of Fe was not measured. The performance and life of SAPS depended on decrease in permeability and retention time due to accumulation of sludge. It is inferred that upgrade of design of the passive treatment system and in-situ treatment using underground void will be necessary for the amelioration of the mine drainage with high metal loading rates.