Contents: 1. A study on the interrelationship of U and Rn in groundwater of hard rock aquifers/Aditya V.S., Chidambaram S., Tirumalesh K., Vasudevan U. and Nepolian M. 2. Hydrogeochemical quality of groundwater in and around Neyveli Lignite Mining Area, Cuddalore District-Cuddalore, Tamil Nadu/Anandhan P., Chidambaram S., Manivannan R., Paramaguru P. and Ganesh N. 3. An attempt to determine the Mountain Front Recharge (MFR) by Using State of Saturation Index (SI) of Carbonate Minerals along the foothills of Courtallam, Tamil Nadu/Banaja Rani Panda, Chidambaram S., Devaraj N. and Ganesh N. 4. Determination of coastal vulnerability using isotope and geochemistry /Chidambaram S., Paramaguru P., Karmegam U. and Johnsonbabu G. 5. Hydrogeochemical and inverse modeling of coastal aquifers of Kalpakkam Region, Tamil Nadu/Chidambaram S., Karmegam U., Prasanna, M.V. and Sasidhar P. 6. A study on the removal of fluoride in groundwater by using natural materials/Manikandan S., Chidambaram S., Ramanathan A.L., Johnsonbabu G. and Karmegam U. 7. Assessment of seawater water intrusion mapping using electrical resistivity tomography in coastal tracts of Pondicherry/Srinivasamoorthy K., Balasubramanian M., Gopinath S., Saravanan K. Prakash R., Vinnarasi, Antony Ravindran A. and Sarma V.S. 8. Identification of submarine groundwater discharge in coastal aquifers using geo chemical parameters/Nepolian M., Chidambaram S., Sarathidasan J., Noble Jacob and Hemant Mohokar. 9. Understanding the influence of colloidal concentration on groundwater chemistry/Pradeep K., Chidambaram S., Manivannan R. and Seshadhri H. 10. Hydrogeochemical characteristics of groundwater at various lithological conditions with space and time/Prasanna M.V. and Chidambaram S. 11. Understanding the seawater intrusion along the coastal aquifers using geochemical techniques/Chidambaram S., Sarathidasan J., Nepolian M., Noble Jacob and Hemant Mohokar. 12. Use of geochemical methods to evaluate the hydraulic connection of aquifers: a case study from Southeast Coast of Tamil Nadu/Singaraja C., Chidambaram S., Anandhan P., Thivya C. and Thilagavathi R. 13. Understanding the distribution of dissolved organic carbon in layered coastal aquifers of Pondicherry region/Thilagavathi R., Chidambaram S., Thivya C., Pethaperumal S. Tirumalesh K. and Singaraja C. 14. A study on the lithological influence on uranium concentration in groundwater of hard rock aquifers of Madurai District, Tamil Nadu/Thivya C., Chidambaram S., Thilagavathi R., Prasanna M.V. and Singaraja C. 15. A study on the impact of landuse pattern on groundwater in and around Chidambaram town/Vasudevan U., Chidambaram S., Thivya C., Thilagavathi R. and Devaraj N. 16. Identification of spatial extent of fluoride contamination in groundwater of Dindigul district, Tamil Nadu - a statistical approach/Manivannan R., Chidambaram S., Anandhan P., Sinagaraja C. and Johnson Babu G.