Significance of MOF adsorbents in uranium remediation from water.

Uranium is considered as one of the most perilous radioactive contaminants in the aqueous environment. It has shown detrimental effects on both flora and fauna and because of its toxicities on human beings, therefore its exclusion from the aqueous environment is very essential. The utilization of metal-organic frameworks (MOFs) as an adsorbent for the removal of uranium from the aqueous environment could be a good approach. MOFs possess unique properties like high surface area, high porosity, adjustable pore size, etc. This makes them promising adsorbents for the removal of uranium from contaminated water. In this paper, sources of uranium in the water environment, human health disorders, and application of the different types of MOFs as well as the mechanisms of uranium removal have been discussed meticulously.

Analysis of Air and Soil Quality around Thermal Power Plants and Coal Mines of Singrauli Region, India.

Singrauli region is known as the energy capital of India, as it generates nearly 21 GW of electricity, supplied to various parts of the northern India. Many coal-based Thermal Power Plants (TPPs) using coal from several nearby coal mines, and numerous industries are set up in this region which has made it as one of the highly polluted regions of India. In the present study, detailed temporal analysis and forecast of carbon dioxide (CO2), nitrogen dioxide (NO2), sulfur dioxide (SO2), and methane (CH4) concentrations retrieved from satellite data have been carried out for the periods 2005-2020. Based on the classical multiplicative model and using linear regression, the maximum concentration of CO2, NO2, SO2, and CH4 in the year 2025 is found to be 422.59 ppm, 29.28 ppm, 0.23 DU, and 1901.35 ppbv, respectively. Detailed analysis shows that carbon dioxide has a 95% correlation with all other trace gases. We have also carried out the geo-accumulation index for the presence of various contaminants in the soil of this region. The geo-accumulation index shows that soil in and around thermal power plants and coal mines is contaminated by heavy metals. The cumulative index shows that soil around Hindalco industries, Bina coal mines, Khadia coal mines, and coal-based TPPs (Anpara and Vindhayachal) are highly polluted and a threat to human population living in the region.

Integrated approach for effective debris mapping in glacierized regions of Chandra River Basin, Western Himalayas, India.

The mapping of debris in glacierized terrain is required for managing the water resources, glacier mass-balance studies and the monitoring of glacier health. Two types of debris i.e. Supraglacial debris (SGD) and periglacial debris (PGD) are derived from the same source i.e., surrounding valley rock and have similar reflectance which makes it difficult to differentiate between them. Hence, in this study a novel integrated approach is proposed where spectral information and thermal data from Landsat 8 Satellite image in conjunction with geomorphometric and topographic parameters extracted from SRTM DEM are utilized to classify SGD and PGD along with other classes in Chandra River Basin (CRB) covering the area of 2422.1 km2 in western Himalayas. Nearly one fourth of the study area is glacierized region while SGD and PGD cover nearly 7% of the study area. Accuracy of the classified data is assessed through comparison with manually digitized data set and minimal difference in area is observed. Results are validated with high resolution (10 m) Sentinel 2a image and data collected from field observations. The SGD is precisely demarcated with 93% accuracy with an overall 83.50% accuracy of classification. Thus, this work presents an efficient, better and prompt method for classifying glacierized areas more effectively than manual delineation at basin/sub-basin level.

Mercury, arsenic, lead and cadmium in waters of the Singrauli coal mining and power plants industrial zone, Central East India.

The present investigation is an attempt to assess the contamination of heavy metals in the ground and surface water of the Singrauli industrial belt area. Pollution indices like heavy metal index (HPI), contamination index (CD) and heavy metal evaluation index (HEI) are used for the evaluation of heavy metal pollution (arsenic As, mercury Hg, cadmium Cd, and lead Pb). Contour maps are constructed to interpret metal spatial distribution. Further, the land-use/land-cover (LULC) maps for the year 2000, 2010 and 2016 are prepared using Landsat satellite data. A total of 48 water samples (Groundwater (27), Surface water (21)) are analysed for heavy metal concentration. Eighty-eight percent of groundwater and 90% of surface water samples are contaminated with Hg. Similarly, high concentrations of Pb and Cd were found in the samples. Surprisingly, all the water samples have As concentration above the WHO permissible limit of 10 ppb. Further, 95% of the samples have an HPI value greater than 100 indicating high heavy metal contamination. CD value denotes contamination of 89% of the samples with heavy metals (As, Hg, Cd, Pb). Through spatial distribution, it can be interpreted that most of the contaminated samples lie near thermal power plants, ash ponds, and coal mines. LULC (land use/land cover) study shows a significant decrease in water bodies by (108 km2), agricultural land by (54 km2) and bare/fallow land by (51 km2) from 2000 to 2016. During these 16 years, there has been a fourfold increase in the overburden, a threefold increase in dumping yards, a 2.5 times increase in urban areas, and a twofold increase in mining areas. Both the environment and the water quality are deteriorating at an alarming rate. Such scientific investigations are relevant for risk management studies of potable water. The knowledge acquired from such assessment shall be considered with utmost priority by concerned authority considering degrading water quality in the study area. Hence, this study is applicable for designing action plans and control measures to reduce water resource pollution.