Contamination, Pollution and Quality

The study deals with the detection of trace elements – Cu, Co, Cd, Zn, Fe, Mn, Ni and Pb along with pH and ORP in the groundwater of Guwahati and its adjacent areas. Toxicity of a metal depends on its concentration, which adversely affects any biological activity. Almost all the metals are toxic at higher concentrations, few in low concentrations and few others even in trace like As, Pb, Hg, Cd etc. The presence of such metals in groundwater is a subject of concern. Groundwater that contains higher amount of metals affects public health to a great extent when it is used for drinking and domestic purposes.

The study attempts to compile and evaluate the status of metal pollution assessment through aquatic sediments in rivers and lakes. The introduction of metallic pollutants into a river, whether it is natural (erosion from its drainage basin) or artificial (anthropogenic), can occur in dissolved or particulate form.

The study deals with adsorption of lead and zinc ions on the bed sediments of river Kali in western Uttar Pradesh. Adsorption is one of the most important processes in water quality control, which influences the transport of pollutants in aquatic environment.

The report deals with the findings of a water quality study of Mansar lake in Udhampur district of Jammu and Kashmir. The water samples from different locations at the surface and from three zones (viz, epilimnion, metalimnion and hypolimnion) were collected and physico-analysis carried out.

In this study, groundwater quality monitoring and evaluation of Greater Guwahati is presented based on the physico-chemical characteristics of thirty samples collected on grid pattern. The various parameters analyzed include pH, electrical conductivity, temperature, Dissolved Oxygen (DO), Total Dissolved Solids (TDS), alkalinity, hardness, Na⁺, K⁺, CA⁺⁺, Mg⁺⁺, NO₃^-, SO4^--, Cl^- and F^-. The results were compared with water quality standards prescribed by BIS and WHO.

The report describes the results of the study of arsenic pollution in groundwater in Nadia as well as the hydro-chemical study of the river Hoogly in West Bengal. The alluvial tract along the river Hoogly covering a stretch of around 470 km encompassing eight districts is affected by arsenic pollution of ground water, the source being geogenic.

The study presents detailed investigations of the chemical quality of groundwater in Jammu and Kathua districts (J & K), carried out to evaluate the suitability of water for various uses. The quality of groundwater of the area has been studied based on the physico-chemical analysis of thirty seven water samples collected from open wells between June and December, 1996.

Various parameters like pH, conductance, alkalinity, hardness, chloride, sulphate, sodium, potassium, calcium and magnesium have been determined for all the samples and compared with the standards to evaluate its suitability for drinking and irrigation purposes.

Irrigation water quality has been computed on the basis of Doneen’s Permeability Index and residual Sodium Carbonate. The higher values of some parameters at certain locations indicate the contamination in groundwater and make the water unsuitable for specific applications.

The report presents a methodology to assess the probability distribution of Dissolved Oxygen (DO) based on the Streeter-Phelp’s equation. The methodology involves the use of first order analysis and Monte Carlo simulation to analyze the uncertainty associated with DO. The mean and standard deviation of the parameters have been assumed as same for the study’s probability distributions.

The study presents a status report on hydrological problems of hard rock areas related to hydrological network design, groundwater quality, failure of open and borewells, regional flood formulae, groundwater balance studies, reservoir sedimentation, hydrological aspects of droughts, forest hydrology and drainage problems of black soil of the hard rock terrain.

The study evaluates groundwater on the basis of widely used graphical methods like Piper, Stiff and US Salinity Laboratory classification. The study concludes that, in general, the groundwater in the area varies from medium salinity to very high salinity, the latter being more common in the irrigated stretches. The irrigators are advised to ensure good land and water management practices in the fields, with particular emphasis on creating favorable leaching and drainage conditions to avoid further development of saline conditions in the area.