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Remote sensing techniques has proved to be an extremely useful tool in morphometric analysis and groundwater studies. Remote sensing techniques with an emphasis on lineament identifications can play a great role in groundwater prospecting in semi-arid hard rock areas of Purulia district. In the present study, morphometric analysis using remote sensing technique has been carried out in parts of Baghmundi block, Purulia district, West Bengal. The parameters worked out include Bifurcation ratio (~), Stream length (I~), Form factor (Pc), Circulatory ratio (Re), and Drainage density (D). The morphometric analysis suggests that fractured, resistant, permeable rocks cover the area, the drainage network not so affected by tectonic disturbances. Using satellite imageries of two dates of IRS, different hydrogeomorphological units have been delineated. Among different hydrogeomorphic units (i) very shallow weathered pediment and (ii) Structural hills/residual hills/inselbergs have very poor ground water prospects, while moderately weathered pediplains and valley fills are good prospective zones for groundwater exploration.

Hydrochemical evaluation of groundwater has been conducted in Bankura I and II Blocks to analyze and determining groundwater quality in the area. Thirty-six groundwater samples were analyzed for their physical and chemical properties using standard laboratory methods. The constituents have the following ranges in the water: pH 6.4-8. ). Sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), magnesium adsorption ratio (MAR), total hardness (TH), and permeability index (PI) were calculated as derived parameters, to investigate the ionic toxicity. Concerned chemical parameters when plotted in the U.S. Salinity diagram indicate that waters are of C 1 -S 1 , C 2 -S 1 and C 3 -S 1 types, i.e., low salinity and low sodium which is good for irrigation. The values of Sodium Adsorption Ratio indicate that the groundwater of the area falls under the category of low sodium hazard. So, there is neither salinity nor toxicity problem of irrigation water, and hence the ground water can safely be used for long-term irrigation. The chemical parameters when plotted in Piper's trilinear diagram are found to concentrate in the central and west central part of the diamond-shaped field. Based on the analytical results, groundwater in the area is found to be generally fresh and hard to very hard. ). According to Gibbs diagrams samples fall in the rock dominance field and the chemical quality of groundwater is related to the lithology of the area. The alkaline earth elements (Ca and Mg) occur in greater abundance than alkaline elements (Na and K). A comparative study of our analytical results with the WHO standards of drinking water indicate that the present waters are also good for drinking purposes.

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Multivariate statistical techniques, cluster and principal component analysis were applied to the data on groundwater quality of Suri I and II Blocks of Birbhum District, West Bengal, India, to extract principal factors corresponding to the different sources of variation in the hydrochemistry as well as the main controls on the hydrochemistry. For this, bore well water samples have been collected in two phases, during Post-monsoon (November 2012) and Pre-monsoon (April 2013) from 26 sampling locations spread homogeneously over the two blocks. Excess fluoride in groundwater has been reported at two locations both in post-and in pre-monsoon sessions, with a rise observed in pre-monsoon. Localized presence of excess iron has also been observed during both sessions. The water is found to be mildly alkaline in post-monsoon but slightly acidic at some locations during pre-monsoon. Correlation and cluster analysis studies demonstrate that fluoride shares a moderately positive correlation with pH in post-monsoon and a very strong one with carbonate in premonsoon indicating dominance of rock water interaction and ion exchange activity in the study area. Certain locations in the study area have been reported with less than 0.6 mg/l fluoride in groundwater, leading to possibility of occurrence of severe dental caries especially in children. Low values of sulfate and phosphate in water indicate a meager chance of contamination of groundwater due to anthropogenic factors.

The Hydrochemical study was carried out in Dwarakeswar watershed area, Bankura and Purulia districts, West Bengal, India, with an objective of understanding the suitability of local groundwater quality for domestic and irrigation purposes. Groundwater samples have been collected from different villages within Dwarakeswar watershed area. The samples have been analysed to determine physical parameters like pH, EC, TDS and Hardness, the chemical parameters like Na, K, Ca, Fe, HCO 3 , SO 4 and Cl. From the analysed data, some parameters like Sodium Absorption Ratio (SAR), Soluble Sodium Percentage (SSP), Residual Sodium Carbonate (RSC), Total Hardness (TH), Magnesium Absorption Ration (MAR) and Kelly's Ratio (KR) have also been determined. The distribution pattern of TDS and chlorides, which are the general indicators of groundwater quality reveals that on an average the ground water is fresh and potable except the ground water in and around Teghari, Gara and Satyatan Primary school where the groundwater is not potable and may affect the health of local population because concentration of TDS exceeds the desirable limits of 500 mg/L. The aerial distribution of Total Dissolved Solids (TDS) reveals that highest concentration is recorded at Gara and Teghri and the lowest concentrations is noted in Suburdih and Kalabani. SAR values were ranged between 0.09 -0.54 meq/L in premonsoon and 0.01 -0.24 meq/L in post-monsoon. It is evident from the whole sample set that the SAR value is excellent in all the samples. Hence, our findings strongly suggest that all the abstracted groundwater samples from the study area were suitable for irrigation. Results of analyses for physical and chemical parameters of groundwater in this area was found to be within the desirable Bureau of Indian Standards and World Health Organisation limits for drinking water.

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Hydrogeochemical investigation of groundwater resources of Kashipur Block, Purulia district, West Bengal has been carried out to assess the water quality for domestic and irrigation uses. Twenty groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids, hardness, major anions (CO 3 2− , HCO 3 − , Cl − , SO 4 2− , F − ) and cations (Ca 2+ , Mg 2+ , Fe 2+ , Na + , K + ). Study results reveal that the groundwater of the area is mostly acidic in nature. The trend amongst average ionic concentrations of cations and anions is Mg 2+ > Ca 2+ > Na + > Fe 2+ > K + and Cl − > HCO 3 − > CO 3 2− > SO 4 2− > F − respectively during the post monsoon whereas the trend for cations and anions are Mg 2+ > Ca 2+ > Na + > K + > Fe and Cl − > HCO 3 − > SO 4 2− > F − > CO 3 − in pre monsoon session, respectively. To explore the ionic toxicity of the study area, the derived parameters like sodium adsorption ratio, soluble sodium percentage, residual sodium carbonate, magnesium adsorption ratio, Kelly's ratio and permeability index were calculated. The hydro geochemical data suggest that weathering of rock forming minerals along with secondary contributions from agricultural and anthropogenic sources are mainly controlling the groundwater composition of Kashipur Block, Purulia District. According to piper diagram, water samples of most of the area of the block are fresh water and in some areas sulphate rich throughout the year. All samples are distributed to central rock dominance category. Groundwater chemistry of this block is mainly controlled by the interaction existing between the litho units and the percolating water into the subsurface domain. However, the groundwater quality and suitability of this study area can be termed as good to moderate with a few exceptions which have been encountered on a local scale.