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Increased concentrations of heavy metals in ash can adversely affect themicrobiological and pedogenetic processes in soil. The aim of this paper is to determine the impact of ash from unburned coal generated in the Kostolac and Gacko coal basins on the quality of soil in the surrounding environment. The investigation included the surface soil layer that was sampled and tested during 2016 and 2017. A total of 30 samples of Kostolac soil and 9 samples of Gacko soil were analyzed for the content of 8 heavy metals: Cu, Pb, Cd, Zn, Hg, As, Cr and Ni. The analyses were carried out by inductively coupled plasma mass spectrometry (ICPMS) technique according to the EPA 6020A method and the following conclusions were made: Kostolac coal ash affects the quality of the surrounding soil in terms of Ni, Cu and Cr as evidenced by the moderately strong correlation of the Ni-Cu pair (k = 0.71), as well as the Cu-Cr pair (k = 0.73) and strong correlation of the Ni-Cr pair (k = 0.82), while the high recorded concentration of Pb, Hg, As and Zn is attributed to other sources of pollution, such as the traffic network and intensive farming activities, and in some cases, its impact is only local. All recorded concentrations of heavy metals are within the remediation values. The effect of ash on soil contamination in the surroundings of the Gacko coal basin is limited to Ni and Cd, with a strong correlation coefficient of this pair (k = 0.82). The recorded overrun of maximum allowed concentration of Cr is evidenced in only 2 samples, and in terms of this element the contamination of the Gacko soil can be considered to be local. It is concluded that prevailing winds play a part in soil pollution. Cluster analysis showed that Ni, Cr and Zn have very similar values in analyzed soil samples from both basins, while a cluster composed of only Hg, in the case of Gacko, indicates lower contamination with Hg compared to the other heavy metals. [ABSTRACT FROM AUTHOR]

The stability of the ashes taken from the three heat-power plants showed that each day of storage in wet landfill causes transformation in their physical and chemical composition. At low temperatures, the spherical grains become brittle and consequently undergo cracking. The studies with a laser diffractometer have shown changes in particle size distribution during the experiment. The pozzolanic activity of the studied ashes significantly decreased under the weathering impact. [ABSTRACT FROM PUBLISHER]

With increased environmental awareness, utilization of bottom ash has become an attractive alternative to disposal. The objective of the present work was to study the environmental impact of bottom ash and to explore the possibility of its potential utilization. Comprehensive characterization of four bottom ash samples collected from different thermal power plants was investigated. Particle size distribution, bulk density, settling characteristics, specific gravity, porosity, permeability, and water-holding capacity etc. were determined for all bottom ash samples. A series of leaching tests was also performed to determine the tracing metal characterization of bottom ash. It is observed that Mn, Mg, Cr, Zn, Ni, and Cu were the most abundant elements while Pb, Mo, Fe, and Co were the least abundant elements. According to the mineral characterization, it is observed that silica (SiO2) and alumina (Al2O3) are primarily present in all samples. Quartz, mullite, and hematite were identified as the mineral phases. The properties of bottom ash give useful information about the utilization of its end use. [ABSTRACT FROM PUBLISHER]

As is the case in many other countries around the world, India's main source of electricity is coal‐fired power plants. In addition to providing energy, the burning of coal also results in large amounts of coal combustion products (CCP), the incombustible material, such as fly ash, left after the coal is burned. These materials are produced in large volume, and if they are not managed or utilized properly, they can pose a danger to the environment. This article discusses the uses of CCP, with a special emphasis on fly ash, and the role that it is currently playing and can continue to play as a mine filler for India's depleted opencast and underground coal mines. [ABSTRACT FROM AUTHOR]

Overload of coal ash (CA) generated from several coal fired plants poses acute problems of disposal and contamination of soil and water resources. Since CA generated from tea factories has not yet been characterized from environmental viewpoints, we attempted to critically characterize the agro-ecological compatibility of CA samples (CA1, CA2, CA3, and CA4) collected from four distantly located tea factories. Among these samples, we found CA3 and CA4 to have low pH and high metal content. Accordingly, we restricted our study to predict the solubility pattern of non-metal and metal ions in CAs by adopting a geochemical model (Visual MINTEQ). Various fractions of metals like Fe, Mn, Cu, Zn, Cr, Ni, and Pb were studied to figure out the mobility pattern of metals in the environment. The results clearly indicate that tea industry derived CA substantially differs from thermal power plant CA as regards several physico-chemical properties, for example, sandy texture, low pH and high nutrient content. Risk evaluation of human exposure to trace elements and the metal fractionation study led us to conclude that CA1 and CA2 are highly compatible with agricultural use. [ABSTRACT FROM AUTHOR]

An investigation of the potential environmental and health impacts in the immediate aftermath of one of the largest coal ash spills in U.S. history at the Tennessee Valley Authority (TVA) Kingston coal-burning power plant has revealed three major findings. First, the surface release of coal ash with high levels of toxic elements (As = 75 mg/kg; Hg = 150 μg/kg) and radioactivity (226Ra + 228Ra = 8 pCi/g) to the environment has the potential to generate resuspended ambient fine particles (<10 μm) containing these toxics into the atmosphere that may pose a health risk to local communities. Second, leaching of contaminants from the coal ash caused contamination of surface waters in areas of restricted water exchange, but only trace levels were found in the downstream Emory and - Clinch Rivers due to river dilution. Third, the accumulation of Hg- and As-rich coal ash in river sediments has the potential to have an impact on the ecological system in the downstream rivers by fish poisoning and methylmercury formation in anaerobic river sediments. [ABSTRACT FROM AUTHOR]

In this article the authors discuss how ignoring emissions of mercury (Hg) from coal ash and desulfurized gypsum will lead to ineffective Hg control in coal-fired power plants in China. Topics include the environmental impact of Hg, increased coal consumption in thermal power plants due to rapid economic development, and the importance of Hg emission control measures at coal-fired power plants.

The authors reveal the adverse impact of the Partizansk Coal-Burning Power Plant (CBPP) in Russia that contaminates soil and natural water. They mention that ash is the main contaminant leading to the problem of overfilled old ash dump and the samples from the Partizanskaya River estuary showed radio-active components. They further suggest two solutions to improve the ecological situation in the river area including ash dump remediation and ash utilization in different industries.

The article discusses the worst outcomes and concern regarding the disposal of the U.S. coal-fired power plants, runoff and seepage from coal ash which pollute groundwater and nearby habitats. It mentions a study regarding the pollutant-related toll on wildlife which asks for new regulations considering the ecological effects and ban on coal-waste disposal. It informs that the U.S. Environmental Protection Agency (EPA) has proposed a policy to regulate coal ash waste.