Contamination, Pollution and Quality

The study applies geostatistical techniques to the groundwater quality data of December 1994 in parts of Jammu district. Groundwater quality deterioration has led to considerable interest in the design of investigative studies and monitoring programs on the issue.

Various management measures need to take into account the spatial and temporal behavior of groundwater. The spatial dependence between observations can be expressed by semi variance, which is a measure of the average similarity between observations at a given distance apart. One of the prime reasons for obtaining a semivariogram is to use it for estimation of the variable at unsampled locations.

A detailed survey of the river Hindon was carried out to understand the nature of waste effluents and their impact on water quality.  As per the study, the river water is subject to varying degrees of pollution, caused by numerous untreated waste outfalls of municipal and industrial effluents.

The main sources, which create pollution in the river, include municipal wastes of Saharanpur, Muzaffarnagar and Ghaziabad districts received through tributaries as well as direct outfalls. In the non-monsoon months, the river is completely dry, right from its origin upto Saharanpur town. The effluents of Nagdev nala and Star Paper Mill at Saharanpur generate the flow of water in the river.

The term skimming well is used for any technique employed with an intention to extract relatively freshwater from the upper zone of the fresh-saline aquifer. The types of skimming wells include: the conventional single strainer well, multi-strainers wells, scavenger wells, radial collector wells and dug wells.

The study attempts to determine the water quality of all available sources of water be it surface, ground or waste water and find out the likely sources of pollution for the Hardwar district of Uttar Pradesh. The physico-chemical parameters of the water were determined. The effect of monsoon on the water quality was studied by collecting and analyzing the pre and post monsoon samples.

The study attempts to determine the adsorption characteristics of bed sediments of rivers for the control of metal pollution. In particular, it looks at adsorption of zinc ions on bed sediments for the river Ganga at Hardwar. In the natural conditions of river water, suspended loads and sediments have an important function of buffering higher metal concentrations of water, particularly by adsorption or precipitation. 

The study on groundwater quality of Greater Guwahati analyses various trace elements in samples and ascertains that their concentration is much higher than the tolerance limit prescribed for drinking water. The trace element analysis focuses on metals such as Cu, Co, Cd, Fe, Zn and Pb.

Owing to the inadequacies of piped water supply, the Greater Guwahati area depends on groundwater from ringwells and tubewells for drinking purposes. Groundwater is mostly polluted from the effluents discharged by industries on land, seepage from sewage lines & tanks and application of pesticides on agricultural land. Due to the low flow velocity, groundwater once contaminated will remain so for longer periods. Metals assume significance because of their greater toxicity, accumulative and non-biodegradable behavior. 

The study attempts to find out the pollution potential in the Hindon river, a polluted river in western Uttar Pradesh. Qualitative and quantitative estimation of pesticides was done using gas chromatography. Among various organic, inorganic and biological water pollutants, pesticides are very dangerous and harmful because of their carcinogenic properties. Pesticides are bio-accumulative and relatively stable and therefore require close monitoring.

The report details out the status of landfill and waste disposal technologies in India & abroad and reviews the scientific studies undertaken to support its design for long-lasting performance. Hydrological considerations play a major role in the selection of landfill sites and in the design and performance of landfills for hazardous waste management. A landfill is a form of a biochemical reactor where the municipal solid waste (MSW) comes into contact with moisture, a catalyst, and gets decomposed into solid waste, gases and liquid contaminants (leachate) resulting in the release of heat. The design of the control and recovery systems requires the estimation of amount and composition of gas and leachate accurately, as also the changes in these with time. Lysimeters are used to simulate the landfill performance.

The report presents a review of several aspects of non-point source of pollution, like extent and effects of pollution in surface and groundwater bodies, pollution control, monitoring, modeling and management options. Non-point source pollution originates from diffuse land areas that contribute pollutants to surface and groundwater bodies. Sediments, nutrients and pesticides are transported from croplands either in a dissolved form in runoff or through adsorption onto eroded soil particles. Apart from this it can also enter groundwater through leaching.