• Economic and Environmental Geology
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• v.30 no.2
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• pp.137-142
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• 1997

At the tailings dam of the disused Brukunga pyrite mine in South Australia, reaction of groundwater with the tailings causes the formation and discharge of sulphuric acid. There is a need to improve remediation efforts by decreasing groundwater flow through the tailings dam. Geophysical methods have been investigated to determine whether they can be used to characterise variations in depth to watertable and map preferred groundwater flow paths. Three methods were used: transient electromagnetic (TEM) soundings, direct current (DC) soundings and profiling, and self potential (SP) profiling. The profiling methods were used to map the areal extent of a given response, while soundings was used to determine the variation in response with depth. The results of the geophysical surveys show that the voltages measured with SP profiling are small and it is hard to determine any preferred channels of groundwater flow from SP data alone. Results obtained from TEM and DC soundings, show that the DC method is useful for determining layer boundaries at shallow depths (less than about 10 m), while the TEM method can resolve deeper structures. Joint use of TEM and DC data gives a more complete and accurate geoelectric section. The TEM and DC measurements have enabled accurate determination of depth to groundwater. For soundings centred at piezometers, this depth is consistent with the measured watertable level in the corresponding piezometer. A map of the watertable level produced from all the TEM and DC soundings at the site shows that the shallowest level is at a depth of about 1 m, and occurs at the southeast of the site, while the deepest watertable level (about 17 m) occurs at the northwest part of the site. The results indicate that a possible source of groundwater occurs at the southeast area of the dam, and the aquifer thickness varies between 6 and 13 m. A map of the variation of resistivity of the aquifer has also been produced from the TEM and DC data. This map shows that the least resistive (i.e., most conductive) section of the aquifer occurs in the northeast of the site, while the most resistive part of the aquifer occurs in the southeast. These results are interpreted to indicate a source of fresh (resistive) groundwater in the southeast of the site, with a possible further source of conductive groundwater in the northeast.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.324-333
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• 1997

The research has been made for the effects of the pollution by the abandoned coal mine drainage on the physical and chemical properties of soil, stream sediment and soil water. The soils overspreaded by the abandoned coal don't develop solum and the bulk density is $1.83g/m^3$, compared with $1.14-1.38g/m^3$ in the other forest soils. The soil pH range in coal bearing region ie, from 4.01 to 4.11 and non-coal bearing soil range is from 5.03 to 5.13. Heavy metals such as As, Cr, Ni, Mo and Ba of coal bearing soils and polluted stream sediments have larger concentration than those of non-coal content and non-polluted. Especially As and Mo concentrations are largely high in coal bearing. The relative ratios $K_2O/Na_2O$ of geochemical elements are higher in coal bearing soil and polluted stream sediments than those of non-coal bearing soils and non-polluted stream sediments as well as black shales of the Changri Formation. However, $MgO+Fe_2O_3+TiO_2/CaO+K_2O$ are the opposite trends, so that the ratios are lower in the polluted regions. The soil water pHs in the polluted regions are the strong acid(pH3.4-4.2) and buffer capacity of the polluted soil is low because canons such as $Na^+$, $K^+$, $Mg^{+2}$are leached by the acidification.

• Korean Journal of Ecology and Environment
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• v.45 no.2
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• pp.218-231
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• 2012

The objectives of this study were to evaluate the physico-chemical water quality, trophic and tolerance guilds in the control ($C_o$) and impacted streams of the abandoned mine, along with the ecological health, using a multimetric health model and physical habitat conditions of Qualitative Habitat Evaluation Index (QHEI), during the period of three years, 2005~2007. Also, eco-toxicity ($EE_t$) enclosure tests were conducted to examine the toxic effects on the outflows from the mine wastewater, using the sentinel species of Rhynchocypris oxycephalus, and we compared the biological responses of the control ($C_o$) and treatment (T) to the effluents through a Necropybased Health Assessment Index ($N_b$-HAI). Tissue impact analysis of the spleen, kidney, gill, liver, eyes, and fins were conducted in the controlled enclosure experiments (10 individuals). According to the comparisons of the control ($C_o$) vs. the treatment (T) in physicochemical water quality, outflows from the abandoned mine resulted in low pH of 3.2, strong acid wastewater, high ionic concentrations, based on an electrical conductivity, and high total dissolved solid (TDS). Physical habitat assessments, based on Qualitative Habitat Evaluation Index (QHEI) did not show any statistical differences (p>0.05) in the sampling sites, whereas, the $M_m$-EH model values in a multimetric ecological health ($M_m$-EH) model of the Index of Biological Integrity (IBI), using fish assemblages, were 16~20 (fair condition) in the control and all zero (0, poor condition) in the impacted sites of mine wastewater. In addition, in enclosure eco-toxicity ($EE_t$) tests, the model values of $N_b$-HAI ranged between 0 and 3 in the controls during the three years, indicating an excellent~good condition (Ex~G), and were >100 (range: 100~137) in the impacted sites, which indicates a poor condition (P). Under the circumstances, organ tissues, such as the liver, kidney, and gills were largely impaired, so that efficient water quality managements are required in the outflow area of the abandoned mine watershed.