Читать книгу Groundwater Geochemistry - Группа авторов - Страница 53

Check dam construction reduces fluoride concentrations and also improves the quality of groundwater in accordance with domestic and agricultural use. The fact that groundwater quality has been improved by recharge using the dams has also been confirmed by spatial variation in the saturation index of minerals. The content of fluoride in wells of groundwater reduces near the check dam whereas areas away from the dam have higher fluoride content. Higher groundwater level and reduced fluoride content near the check dam represent the major advantage of recharging from the dam. The fluoride concentration becomes lower than the permissible limit of BIS (Bureau of Indian Standards) around the area of 4 km² near a dam present in Krishnagiri District of Tamil Nadu (Gowrisankar et al. 2017). One of the known examples of in‐situ method in India is the Anantapur district check dam construction in Andhra Pradesh, which aided in reduction of fluoride content of groundwater (Bhagavan and Raghu 2005).