**5.1 Methodology**

The methodology comprises of field procedures and analytical techniques. The field procedures include mapping techniques, well inventory and collection of

groundwater samples and survey on health implications caused by F. The analytical techniques include the determination various physicochemical parameters of collected groundwater samples.

#### **5.2 Field procedures**

The mapping techniques covered geological mapping, demarcation of geomorphological features and preparation of slope, soil, drainage and land use/land cover maps. This work was carried out, using the Survey of India toposheets of 56P/12, 56P/16, 57M/9, and 57M/13 on a scale of check 1: 50,000. Indian Remote Sensing Satellite (IRS) ID Linear Imaging Self Scanner (LISS) III of geocoded false color composite of December 9, 2012 on 1:50,000 scales are used to get information on soils, geomorphological features, lithology, lineaments, and land use/land cover with a limited ground truth. Geological mapping was carried out by marking the contacts between the geological formations as well as the structural features. Geomorphological features were demarcated based on the field observations and the available literature.

Fifty groundwater samples were collected in pre-monsoon (month of May) and post-monsoon (November) seasons during the year 2012 in the study area. Prior to water sampling, sampling bottles soaked in 1:1 HCl for 24 h were rinsed with distilled water, followed by deionized water. They were washed again prior to each sampling of the filtrates. The bottles were tightly capped to protect the samples from atmospheric CO2, adequately labeled, and preserved in the refrigerator till they were taken to laboratory for measurement. Data on location of wells, geographic coordinates, type of well, depth to groundwater level, and water taste was collected. The variations in the groundwater levels in the wells were recorded, using a water level recorder.

The people living in the study area suffering from different stages of fluorosis by consuming fluoridated water were identified. The dental fluorosis stages were identified by adopting Dean's classification [10]. The fluoride levels are examined in the human body through the analysis of urine samples of the effected persons.
