Particulate matter samples were collected using a dichotomous sampler at a residential area of Vashi situated in Navi Mumbai, India during the period of 2008. The sampler facilitates the simultaneous collection of atmospheric particulates in coarse and fine size fractions. The filter samples collected were analysed for trace elements using Proton Induced X-ray Emission (PIXE) technique. The particulate matter trends show higher concentration during winter season compared to other seasons. High concentrations of elements related to soil and sea salt were found in the coarse fraction of particulate matter. Enrichment Factor (EF) analysis with respect to Fe showed enrichment of Cu, Cr, and Mn only in the fine fraction suggesting their origin from anthropogenic sources. The EF value was observed to be maximum for As, Pb and Zn in the fine particulates. However, crustal and marine derived elements showed very low EF values indicating their origin from soil and sea salt respectively. The Principal Component Analysis (PCA) based multivariate studies identified soil, sea salt and combustion as common sources for coarse and fine particles. Additionaly a source contributing to coarse fraction Br concentration as well as an industrial and Se source contributing to fine fraction particles has been identified.

Precipitation is the best scavenger for the particulates and dissolved gaseous pollutants present in the atmosphere. The chemical composition of precipitation is dominated by a number of in-cloud and below-cloud scavenging processes. The present study is aimed at analyzing the chemical composition of rainwater in the relatively less industrialized part of Mumbai. The pH of rainwater in this region ranges from 4.8 to 6.4. The percentage contributions of ions were calculated and the major contributing ions were calcium (28%), chloride (23%), sodium (18%), sulfate (14%), magnesium (11%), ammonium (4%), potassium (1%), and nitrate (1%). The correlation coefficient is highest for Na and Cl (r(2) = 0.99), giving a clear indication of contribution from sea salt. Sulfate and nitrate ions also show a very good correlation (r(2) = 0.90), which may be due to their coemission from fossil fuel combustion. Acidification caused by these ions is neutralized by Ca, Mg, and NH(4) ions. The neutralization effect due to these ions is validated by calculating the neutralization factor (NF). The NF values are in the order Ca > Mg > NH(4). The major source contributors for the ions in precipitation are sea salt (Na, Cl, and K) and fossil fuel combustion (SO(4) and NO(3)). These assumptions are supported by the values of wet-only ratio, enrichment factor, and percent sea salt fraction.

Studies on leaching behavior of metals associated with coal fly ash (FA) are of great concern because of possible contamination of the aquatic environment. In the present study, leaching behavior of metals (As, Se, Cr, Pb, V, Zn, etc.) in two different FA samples (FA1 and FA2) was investigated at various pH (2-12), temperatures of leachate solution and using TCLP. At pH 2, the highest leaching was observed for Fe (21.6 and 32.8 µg/g), whereas at pH 12, Arsenic was found to have the highest leaching (1.5 and 2.4 µg/g) in FA1 and FA2. Leachate solution temperature showed a positive effect on the metal's leachability. In TCLP, most of the metal's leachability was observed to be higher than that of batch leaching tests. The present study suggests that, leaching of As and Se from FA samples can moderately affect ground/surface water quality at the study locations.

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In developing countries concentration on pollutants produced by industries such as dyeing, tanneries industries are exceptionally high. The disposal of untreated industrial waste water similar to dyeing effluent on soil is a widespread practice in developing nations. The unprocessed effluents severely deteriorate the soil properties. The study on dyeing effluents from industries affects engineering properties of soil. Hence the soil properties have to be improved for intensification of soil for the constructional activities. The soil properties are very much exaggerated by dyeing effluent which produces the soil and water pollution. In this study textile industry effluent is taken as pollutants and laboratory experiments are carried. The affected soils were treated with marble dusts as admixture to improve the soil properties. For assessment polluted and unpolluted soil samples are treated with 20% of dyeing effluent and tests were conceded out to identify an extent of the contamination. The cured samples show a decrease in strength values up to 30% with raise in the percentage of infectivity (dyeing effluent). The geotechnical properties and their stabilization using marble dust are determined with mixtures and explored.