Hydrogeochemical Characteristics of Groundwater at the Xikuangshan Antimony Mine in South China

The hydrogeochemical influence of the Xikuangshan antimony mine on groundwater quality was investigated by analyzing groundwater from 24 springs in the area for major and trace elements. The samples had a pH of 7.6–8.5; total dissolved solids ranged from 125 to 607 mg/L. The groundwater was dominated by alkaline earths (Ca²⁺ + Mg²⁺) over the alkalies (Na⁺ + K⁺), and weak acids \(\left( {{\text{HCO}}_{ 3}^{ - } } \right)\) over strong acids \(\left( {{\text{SO}}_{4}^{2 - } + {\text{Cl}}^{ - } } \right)\). Calcite was generally supersaturated and gypsum was always undersaturated, while dolomite was undersaturated in 34 % of the samples. Iron was negatively correlated with Ca²⁺, Mg²⁺, and \({\text{SO}}_{ 4}^{ 2- }\), which is consistent with Fe removal during acid buffering. Scatter diagrams and correlation coefficients between the major ions indicate dissolution of carbonates and gypsum as major processes, which could promote calcite precipitation.     

Influence of Drainage with High Levels of Water-Soluble Salts on the Environment in the Verhnekamskoe Potash Deposit,Russia

Saline drainage from slurry storage facilities can deteriorate the properties of clay barriers in the beds of embankment dams and slurry ponds and cause saline drainage to infiltrate into groundwater. The chemistry of slurry material, drainage, springs, surface water, and soils was studied near the slurry storage facility of the Verhnekamskoe potash mine (Russia). Our study showed that the Na–Cl type mine drainage water, with high amounts of nitrogen compounds, increased the salinity of the groundwater and surface water, and the river valley ecosystems. As a result of ion exchange and leaching, the soil, groundwater, and surface water have elevated levels of \({\text{C}}{{\text{a}}^{2+}}\), \({\text{M}}{{\text{g}}^{2+}}\), \({\text{SO}}_{4}^{{2 - }},\) and \({\text{F}}{{\text{e}}_{{\text{total}}}}\), and extremely high \({\text{~N}}{{\text{a}}^+}\) and \({\text{C}}{{\text{l}}^ - }{\text{~}}\) values. Iron-rich precipitates and hydrogen sulfide tend to form down-gradient in the saline, water-logged seepage areas.     

The Hydrogeochemistry of Arsenic in the Clara Mine,Germany

Abstract.   The oxidative dissolution of primary arsenic-bearing sulfide minerals in barite-fluorite veins is a potential source of arsenic in the Clara Mine. Geological structures, especially the mineral veins, provide potential pathways for the water. The highest arsenic concentrations are found in ground water within the eastern part of the mine. Arsenic and major ions are positively correlated and provide evidence that arsenic is likely derived locally from the water-vein/water-rock interaction. Geochemical modeling with PHREEQC shows all the arsenate mineral phases to be significantly undersaturated, although secondary arsenate minerals are common in the oxidized part of the deposit. The mine waters plot near the boundary of Fe(OH)₃ and Fe²⁺ in the pH-Eh diagram for the As-Fe-S-H₂O-system. Arsenic occurs as the 5-valent species and . Statistical analysis illustrates a strong association between As, Fe, pH, and HCO₃. Oxidation of the primary As-bearing minerals, such as pyrite and arsenopyrite, and the subsequent behavior of the oxyanion, arsenate, generally controls the distribution and speciation of arsenic. The low concentrations of dissolved As is due to co-precipitation and adsorption of arsenate by Fe, Al, and Mn (oxy)hydroxides.     

One approach to the prediction of rock bursts

Conclusions Thus, as a result of the experimental discovery of previously unknown pendulum waves, the elementary carriers of which are geoblocks differing in hierarchic level, with dynamic-kinematic characteristics that depend on the stress-strain state of the rock masses and the dimensions of the focal zones of rock bursts and explosions, we are able to propose a new approach to the prediction of catastrophic events. Here, as diagnostic indexes with respect to the critical stages of stress concentration for focal zones of rock bursts that are being formed, we can use the angular characteristic θ of the conical envelope of the μ-wave packets and their energy characteristics Ψ₁ and Ψ₂. With such an approach, seismograms from technological explosions can be used as integral information in a new system of geomechanical monitoring. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 3–15, November–December, 1998.     

Specifics of the sulfuric-acid processing of galena concentrates in the presence of nitrous acid

Conclusions  

The adoption and adaptation of passive treatment technologies for mine waters in the United Kingdom

During the 1990s, passive treatment technology was introduced to the United Kingdom (UK). Early hesitancy on the part of regulators and practitioners was rapidly overcome, at least for net-alkaline mine waters, so that passive treatment is now the technology of choice for the long-term remediation of such discharges, wherever land availability is not unduly limiting. Six types of passive systems are now being used in the UK for mine water treatment:

Alteration of the permeability tensor around a grouped explosion

Conclusions The results derived in the paper indicate that the permeability of the medium deteriorates along a straight line connecting the chamber centers. At the same time, the components k_r and k_ω of the permeability tensor increase. This gives a new confirmation to the conclusion made earlier that infiltration flows between spherical cavities will be practically absent along the shortest distance, and that the hydrodynamic connection between the cavities will occur through areas marked by circled minuses in Fig. 4. Our calculations thus indicate that the distribution of permeability factor near the destruction zone of confined explosions is a rather complex function of three-dimensional coordinates, described qualitatively in Fig. 4 (the increase and decrease areas). This distribution of is bound to affect the pattern of infiltrational interaction of the destruction zones and should be taken into consideration when planning a cluster blast. Institute of Engineering Physics, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 43–50, September–October, 1985.     

Hydrogeomechanical problems in mining

The hydrogeomechanical problems of mining are considered, which deal with rocks and ground water as a single mechanical system. Among these problems are the openpits slopes stability, rocks consolidation and surface subsidence due to ground water level lowering, water inrushes into mine workings, rock bursts prevention by using the water injection into the advance boreholes, etc. The paper contains the basic theoretical grounds, as well as in-situ and laboratory methods for the investigation of these processes. The combined study of ground water regime and rock deformations has resulted in the theoretical substantiation of the hydrodynamic and geomechanical processes within the scope of unique scientific direction-hydrogeomechanics (Mironenko, 1974). The hydrogeomechanical models are widely used now for the analysis and forecasting the extremely important processes connected with the safe and efficient mining operations, as well as with the protection of geological medium. Among these processes are:

Comparison of the overall circuit performance in the cement industry: High compression milling vs. ball milling technology

In cement production, tube mills having multi-chambers are traditionally used either in open or closed circuit operations. After the introduction of high compression grinding mills (High pressure grinding rolls (HPGR), vertical roller mill (VRM) and Horomill), various circuit configurations have been developed for energy efficient grinding. In this study, in order to evaluate and compare the performances of these cement grinding technologies, industrial scale data were collected from HPGR-ball mill, VRM, Horomill and multi-chamber ball mill closed circuits.The grind abilities of the raw materials of all circuits were varying in a narrow range of 14–20 kWh/t. The specific energy consumptions of the grinding equipment and the standard bond work indexes, used 100 μm screen, of raw materials are given below.     

11.

Energy content of the nonexplosive excavation of rock by excavators with a dynamic scoop     

A. R. Mattis  G. D. Zaitsev  A. A. Kragel' 《Journal of Mining Science》1998,34(3):242-248

Conclusions  

Energy content of the nonexplosive excavation of rock by excavators with a dynamic scoop

Conclusions  

Biotic and Abiotic Sequestration of Selenium in Anoxic Coal Waste Rock

Mobile selenium oxyanions (\({\text{S}}{{\text{e}}^{{\text{VI}}}}{\text{O}}_{4}^{{2 - }}\) and \({\text{S}}{{\text{e}}^{{\text{IV}}}}{\text{O}}_{3}^{{2 - }}\)) can be sequestered by biotic or abiotic reduction to non-mobile species or by adsorption to mineral surfaces. Microbial analyses and geochemical batch testing with samples collected from a coal waste rock dump in the Elk Valley, British Columbia, Canada were conducted to assess whether Se can be sequestered in anoxic, waste rock by these mechanisms. Bacteria that reduce Se(IV) and Se(VI) to Se(0) were isolated from the waste rock. Isolates that reduce Se(IV) to Se(0) were present in a water sample collected from an underlying rock drain. Three isolates were affiliated with Pseudomonas and Arthrobacter. One isolate was a putatively novel species. The production of Se(0) was confirmed by X-ray absorption near edge spectroscopy of a red precipitate isolated from a broth media containing rock-drain water. No adsorption or reduction of Se(VI) was observed in anoxic, abiotic (sterile) batch tests conducted with waste rock and a 1.0 mg/L Se(VI) solution, whereas Se(IV) was adsorbed by the waste rock and subsequently reduced to Se(0) in abiotic batch tests with a 0.7 mg/L Se(IV) solution. In non-sterile batch tests using waste rock and rock-drain water (0.39 mg/L Se(VI)), Se(VI) was biologically reduced to Se(IV), which was subsequently removed from solution by a combination of bioreduction, adsorption, and possibly abiotic reduction. This study suggests that, under anoxic conditions, Se sequestration in waste rock may occur via biotic reduction of Se(VI) to Se(IV) followed by adsorption of Se(IV) and abiotic and biotic reduction of Se(IV) to Se(0).     

Refinement of methods of beneficiation of finely disperse minerals

Conclusions  The prospect of switch-over of the industry to processing lean materials raises the problem of beneficiation of finely disperse placers of noble metals, the profitability of realization of which lies in raising the efficiency of separation processes by reducing frictional forces in the course of implementation of the technological processes and by employing modern technologies for beneficiation. The engineering—technological solutions worked out are distinguished by ecological safety during implementation of the beneficiation processes. The proposed schemes of beneficiation and primary processing of finely disperse minerals may be used:

Use of technogenic and natural solutions in hydrometallurgical operations

Conclusions  The results obtained here demonstrate the promise of using technogenic and concentrated condensates of hightemperature heat carriers to perform leaching as part of the processing of copper-nickel ores. The productive solutions that were obtained have high contents of the useful components (grams and tens of grams per liter) and could be converted to the desired end products by proven methods [12]. The following problems should be addressed first in future research in this area:

Assessment of Soil and Water Contamination at the Tab-Simco Coal Mine: A Case Study

In 1996, the Tab-Simco site, an abandoned coal mine 10 km southeast of Carbondale, Illinois, was listed as one of the most highly contaminated AMD sites in the mid-continent region. A suite of impacted soil and water samples were collected from various locations to characterize the current extent of AMD pollution, following standard U.S. EPA protocols. The mean pH of soil and water samples were found to be 2.69 and 2.07, respectively. The mean sulfur content of the soil samples was 0.5 %. The AMD-impacted soils contained high concentrations of Fe, Zn, Ni, Cr, Cu, Pb, and As. The AMD also contained high concentrations of Fe, As, Zn, Pb, Cr, Al, Cd, Cu, and Ni, as well as \({\text{SO}}_{4}^{2 - }\), all of which were significantly above their U.S. EPA permissible limits for surface water.     

Displacement of vibrational devices

Conclusions  The following characteristics of self-transportation have been established.

Wave processes when driving metal pipes into the ground using shock-pulse generators

Conclusions