Groundwater Quality Mapping in Crystalline Rock Aquifers of Tindivanam Taluk, Tamil Nadu Integrating with Remote Sensing, GIS and Space Models

Determination of groundwater quality and quantity in crystalline basement terrains is a complex
problem. More than half of the surface area of the continents is covered with hard rocks. In hard rock
areas, groundwater is found in cracks and fractures of the local rocks. Hardrocks can typically acquire
water tolerable to good quality. It is a hard task to identify suitable aquifers in a crystalline landscape.
In Tindivanam Taluk, Tamil Nadu, groundwater is the major source of water for the local inhabitants.
The Taluk consists of the crystalline basement and the groundwater development through dug and
bore wells. This study focuses on the combination of remote sensing and GIS to produce
comprehensive groundwater quality zones for the study area. The water quality attribute, such as
TDS, TH, CR, and Cl, was constructed as point attributes (location wells) for contour construction.
The attributes selected for drinking (TDS), for domestic (TH), for industrial (CR) and for agricultural /
drinking (CL) purposes. TDS and TH integration was accomplished command union I and combined
CR and Cl to generate union II maps. The union III was created by the integration of union I and union
II, which is the final output map of the overlay analysis. From the final integrated map, it is inferred
that freshwater zone exists in the north and south parts, tolerable quality water covers in major parts
and the low-quality water zone exists in limited areal extent in the study area.