Hydrogeochemical studies of groundwater in Salem District, Tamil Nadu (India).

Salem is one of the industrial, agricultural and mineral deposit based district in Tamil Nadu. In this paper, an attempt is made to assess the quality of groundwater in this district, during the month of May 2007 (pre-monsoon). The government of Tamil Nadu has divided the district into twenty blocks. Sixty six samples were collected covering all the blocks of the district except Yercaud which is a structural hill. The collected samples were tested for the following parameters: electrical conductivity, turbidity, pH, total hardness, iron, chlorides, total dissolved solids, calcium, magnesium, potassium, manganese, sulphate, nitrate, nitrite and total alkalinity. The test results were interpreted using IS 10500-1991, statistical methods, SAR, USSL classification and Piper's trilinear diagram. Based on the interpretation it is concluded that the study area is mostly influenced by the presence of electrical conductivity, total dissolved solids, total hardness, chloride and total alkalinity whereas the other minerals and salts play a minor role.