Abstract: In this study, the effect of coal mining activities on lead and cadmium concentrations and distribution in soil was investigated in Hyrcanian forest, North Iran. 16 plots (20×20 m2) were established by systematic-randomly (60×60 m2) in an area of 4 ha (200×200 m2-mine entrance placed at center). An area adjacent to the mine was not affected by the mining activity; considered as the controlled area. In order to investigate soil lead and cadmium concentration, one sample was taken from the 0-10 cm in each plot. To study the spatial pattern of soil properties and lead and cadmium concentrations in the mining area, an area of 80×80m2 (the mine as the center) was considered and 80 soil samples were systematic-randomly taken (10 m intervals). Geostatistical analysis was performed via Kriging method and GS+ software (version 5.1). In order to estimate the impact of coal mining activities on soil quality, pollution index was measured. Lead and cadmium concentrations were significantly higher in mine area (Pb: 10.97±0.30, Cd: 184.47±6.26 mg.kg-1) in comparison to control area (Pb: 9.42±0.17, Cd: 131.71±15.77 mg.kg-1). The mean values of the PI index indicate that Pb (1.16) and Cd (1.77) presented slightly polluted. Results of the NIPI index showed that Pb (1.44) and Cd (2.52) presented slight pollution and moderate pollution respectively. Results of variography and kriging method showed that it is possible to prepare interpolation maps of lead and cadmium around the mining areas in Hyrcanian forest. According to results of pollution and risk assessments, forest soil was contaminated by heavy metals (lead and cadmium); therefore, using reclamation and remediation techniques in these areas is necessary.
Abstract: The expansion of large scale coal mining into forest areas is a potential hazard for the local biodiversity and wildlife. The objective of this study is to provide a picture of the threat that coal mining poses to the forests of the East Bokaro landscape. The vulnerable forest areas at risk have been assessed and the priority areas for conservation have been presented. The forested areas at risk in the current scenario have been assessed and compared with the past conditions using classification and buffer based overlay approach. Forest vulnerability has been assessed using an analytical framework based on systematic indicators and composite vulnerability index values. The results indicate that more than 4 km2 of forests have been lost from 1973 to 2016. Large patches of forests have been diverted for coal mining projects. Forests in the northern part of the coal field within 1-3 km radius around the coal mines are at immediate risk. The original contiguous forests have been converted into fragmented and degraded forest patches. Most of the collieries are located within or very close to the forests thus threatening the biodiversity and hydrology of the surrounding regions. Based on the vulnerability values estimated, it was concluded that more than 90% of the forested grids in East Bokaro are highly vulnerable to mining. The forests in the sub-districts of Bermo and Chandrapura have been identified as the most vulnerable to coal mining activities. This case study would add to the capacity of the forest managers and mine managers to address the risk and vulnerability of forests at a small landscape level in order to achieve sustainable development.
Abstract: Coal mining is well known to cause considerable environmental impacts, including trace element contamination of soil. This study aimed to assess the trace element (As, Cd, Co, Cu, Ni, Pb, Sb, and Zn) contamination of soil in the vicinity of coal mining activities, using the case study of Asam-asam River basin, South Kalimantan, Indonesia, and to assess the human health risk, incorporating total and bioavailable (water-leachable and acid-leachable) concentrations. The results show the enrichment of As and Co in soil, surpassing the background soil value. Contamination was evaluated based on the index of geo-accumulation, Igeo and the pollution index, PI. Igeo values showed that the soil was generally uncontaminated (Igeo ≤ 0), except for elevated As and Co. Mean PI for Ni and Cu indicated slight contamination. Regarding the assessment of health risks, the Hazard Index, HI showed adverse risks (HI > 1) for Ni, Co, and As. Further, Ni and As were found to pose unacceptable carcinogenic risk (risk > 1.10-5). Farming, settlement, and plantation were found to present greater risk than coal mines. These results show that coal mining activity in the study area contaminates the soils by particular elements and may pose potential human health risk in its surrounding area. This study is important for setting appropriate countermeasure actions and improving basic coal mining management in Indonesia.
Abstract: The environmental impacts arising from mining activities affect the air, water, and soil quality. Impacts may result in unexpected and adverse environmental outcomes. This study reports on the impact of coal production on sediment in Sydney region of Australia. The sediment samples upstream and downstream from the discharge points from three mines were taken, and 80 parameters were tested. The results were assessed against sediment quality based on presence of metals. The study revealed the increment of metal content in the sediment downstream of the reference locations. In many cases, the sediment was above the Australia and New Zealand Environment Conservation Council and international sediment quality guidelines value (SQGV). The major outliers to the guidelines were nickel (Ni) and zinc (Zn).
Abstract: Biological processes based on oxidation of sulfur
compounds by chemolithotrophic microorganisms are emerging as an
efficient and eco-friendly technique for removal of sulfur from the
coal. In the present article, study was carried out to investigate the
potential of biodesulfurization process in removing the sulfur from
lignite coal sample collected from a Mongolian coal mine. The batch
biodesulfurization experiments were conducted in 2.5 L borosilicate
baffle type reactors at 35 ºC using Acidithiobacillus ferrooxidans.
The effect of pulp density on efficiency of biodesulfurization was
investigated at different solids concentration (1-10%) of coal. The
results of the present study suggested that the rate of desulfurization
was retarded at higher coal pulp density. The optimum pulp density
found 5% at which about 48% of the total sulfur was removed from
the coal.
Abstract: By GEO5 FEM program with four rockfill slope
modeling and stability analysis was performed for S1, S2, S3 and
S4 slopes where landslides of the shalefills were limited. Effective
angle of internal friction (φ'°) 17°-22.5°, the effective cohesion (c')
from 0.5 to 1.8 kPa, saturated unit weight 1.78-2.43 g/cm3, natural
unit weight 1.9-2.35 g/cm3, dry unit weight 1.97-2.40 g/cm3, the
permeability coefficient of 1x10-4 - 6.5x10-4 cm/s. In cross-sections
of the slope, GEO 5 FEM program possible critical surface tension
was examined. Rockfill dump design was made to prevent sliding
slopes. Bulk material designated geotechnical properties using also
GEO5 programs FEM and stability program via a safety factor
determined and calculated according to the values S3 and S4 No.
slopes are stable S1 and S2 No. slopes were close to stable state
that has been found to be risk. GEO5 programs with limestone rock
fill dump through FEM program was found to exhibit stability.
Abstract: Coal is an important non-renewable energy source of
and can be associated with radioactive elements. In Figueira city,
Paraná state, Brazil, it was recorded high uranium activity near the
coal mine that supplies a local thermoelectric power plant. In this
context, the radon activity (Rn-222, produced by the Ra-226 decay in
the U-238 natural series) was evaluated in groundwater, river water
and effluents produced from the acid mine drainage in the coal reject
dumps. The samples were collected in August 2013 and in February
2014 and analyzed at LABIDRO (Laboratory of Isotope and
Hydrochemistry), UNESP, Rio Claro city, Brazil, using an alpha
spectrometer (AlphaGuard) adjusted to evaluate the mean radon
activity concentration in five cycles of 10 minutes. No radon activity
concentration above 100 Bq.L-1, which was a previous critic value
established by the World Health Organization. The average radon
activity concentration in groundwater was higher than in surface
water and in effluent samples, possibly due to the accumulation of
uranium and radium in the aquifer layers that favors the radon
trapping. The lower value in the river waters can indicate dilution and
the intermediate value in the effluents may indicate radon absorption
in the coal particles of the reject dumps. The results also indicate that
the radon activities in the effluents increase with the sample
acidification, possibly due to the higher radium leaching and the
subsequent radon transport to the drainage flow. The water samples
of Laranjinha River and Ribeirão das Pedras stream, which,
respectively, supply Figueira city and receive the mining effluent,
exhibited higher pH values upstream the mine, reflecting the acid
mine drainage discharge. The radionuclides transport indicates the
importance of monitoring their activity concentration in natural
waters due to the risks that the radioactivity can represent to human
health.
Abstract: There are many sources trough which the soil get
enriched and contaminated with REEs. The determination of REEs in
environmental samples has been limited because of the lack of
sensitive analytical techniques. Soil samples were collected from
four sites including open cast coal mine, natural coal burning, coal
washery and control in the coal field located in Dhanbad, India.
Total concentrations of rare earth elements (REEs) were determined
using the inductively coupled plasma atomic absorption spectrometry
in order to assess enrichment status in the coal field. Results showed
that the mean concentrations of La, Pr, Eu, Tb, Ho, and Tm in open
cast mine and natural coal burning sites were elevated compared to
the reference concentrations, while Ce, Nd, Sm, and Gd were
elevated in coal washery site. When compared to reference soil,
heavy REEs (HREEs) were enriched in open cast mines and natural
coal burning affected soils, however, the HREEs were depleted in the
coal washery sites. But, the Chondrite-normalization diagram showed
significant enrichment for light REEs (LREEs) in all the soils. High
concentration of Pr, Eu, Tb, Ho, Tm, and Lu in coal mining and coal
burning sites may pose human health risks. Factor analysis showed
that distribution and relative abundance of REEs of the coal washery
site is comparable with the control. Eventually washing or cleaning
of coal could significantly decrease the emission of REEs from coal
into the environment.
Abstract: Typically thermal power plants are located near to
surface coal mines that produce huge amount of fly ash as a waste
byproduct. Disposal of fly ash causes significant economic and
environmental problems. Now-a-days, research is going on for bulk
utilization of fly ash. In order to increase its percentage utilization, an
investigation was carried out to evaluate its potential for haul road
construction. This paper presents the laboratory California bearing
ratio (CBR) tests and evaluates the effect of lime on CBR behavior of
fly ash - mine overburden mixes. Tests were performed with different
percentages of lime (2%, 3%, 6%, and 9%). The results show that the
increase in bearing ratio of fly ash-overburden mixes was achieved
by lime treatment. Scanning electron microscopy (SEM) analyses
were conducted on 28 days cured specimens. The SEM study showed
that the bearing ratio development is related to the microstructural
development.