Document Type : Primary Research paper
Research Scholar, Centre for Natural Hazards and Disaster Studies, University of Madras, Chennai - 600005.
Director - Gill Research Institute, Professor and Head (former) Centre for Natural Hazards and Disaster Studies, University of Madras, Chennai - 600005
India is the first country among the top ten groundwater abstracting countries
and groundwater draft of India was 251 km2 (UNFAO, 2016). Population growth,
evaporation loss, land use changes, over extraction of groundwater, frequent monsoon
failure and climate change have caused water scarcity in India. Tamil Nadu is an agrarian
state basically depending upon groundwater for agricultural activities, food production and
domestic use. Groundwater occurs in weathered, fractured and jointed rock formations.
Tamil Nadu faces twin challenges of groundwater scarcity and groundwater quality.
Groundwater is being polluted by many sources like discharge of industrial effluents,
dumping of municipal solid wastes, pesticides and fertilizers used in agricultural activities
and bio wastes. The effects of groundwater pollution are horizontally and vertically.
Spread of water prone diseases is due to groundwater pollution. The groundwater
geochemistry study is very essential for good water quality management for drinking and
irrigation. For the assessment of groundwater quality in the Araniyar-Kosasthalaiyar sub
basin, in which cluster of chemical industries located in the eastern part, spatial
interpolation and Pollution Index of Groundwater (PIG) have been employed using the
water quality parameters such as pH, EC, TDS, TH, Ca, Mg, Na, K, Cl, SO4, NO3 and F.
The spatial distribution of Cl, Na, K, EC, TDS and TH shows that abnormal concentration
exhibits in the industrial hazard buffer zone and proves pollutions are due to industries.
The analysis of PIG confirms that 11.64 Sq.Km area in the industrial hazard zone area has
the high pollution and 3.61 Sq.Km area fall in very high class in pre monsoon period and
38.o2 Sq.Km area has high class pollution and 34.54 Sq.Km area fall in very high class
pollution in post monsoon period.