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The dust emission from the mining area is the primary source of air pollution for the surrounding environment. This paper deals with the study of baseline air quality assessment and air pollution modeling exercise for a mica, feldspar, and quartz mine to predict the maximum dust concentration from the mine with and without control measures. Baseline PM10, PM2.5, SO2, and NO2 levels in the buffer zone of the planned mine site were found to be 53.1–79.5, 20.2–43.2, 16.6–31.2, and 21.2–50.1 mg m−3, respectively, and these values were lesser than the corresponding permissible limit of 100, 60, 80, and 80 µg m−3. The respective predicted PM10 and PM2.5 levels will be 73.9–97.1 and 31.9–44.2 mg m−3 without control measures, and 73.5–82.5 and 31.8–43.8 µg m−3 with control measures during operation of the mine. It is estimated that PM10 and PM2.5 will remain below the permissible limit in the buffer zone of the mine. The paper suggests effective air pollution control measures, including a description of the developed smart dry fog dust suppression system and wirelessly controlled sprinkling system for applications at various dust emitting sources in the mining area. [ABSTRACT FROM AUTHOR]

Multi-electrode resistivity imaging survey with 48 electrodes was carried out to assess the extent of salinity inland, in the shallow subsurface in Nellore district, Andhra Pradesh, in the Eastern Ghats Mobile Belt (EGMB) region. Resistivity data were recorded using Wenner-Schlumberger configuration at nine sites along a profile of about 55 km in length, laid perpendicular to the coast. An average spacing of 6 km is maintained between each site. Assessment of groundwater salinity in the study area was made by joint interpretation of the two-dimensional (2D) geoelectrical models of all the sites together with the geochemical analysis results of water samples and geology. At sites closer to the coast, 2D geoelectrical models of the subsurface indicate low resistivities (2-50 Ωm) in the depth range from surface up to 15 m. Such low resistivities are due to the high salinity of the groundwater. Geochemical analysis results of water samples at six locations close to the electrical resistivity survey sites also suggest high salinity and high concentrations of total dissolved solids and other chemicals at sites closer to the coast. Away from the coast, the resistivities in the depth range from surface up to 15 m vary in the range of 50-150 Ωm. Accordingly, the chemical analysis of water samples collected at these sites also showed relatively low levels of salinity and salt concentrations in them. However, away from the coast, the resistivities vary in the range of 150-1500 Ωm in the depth range from 20-40 m. While the aquaculture and agriculture activities may contribute to high salinity at the sites closer to the coast, the presence of deep-seated paleochannels aiding in transporting seawater inland, and water-rock interactions are suspected to be the chief causes for notable salinity at places away from the coast at shallow depths. We opine that the high salinity at shallow depths, coupled with the deep-seated paleochannels transporting seawater, could pose problems to probe further depths particularly using electromagnetic induction methods in the study region. [ABSTRACT FROM AUTHOR]