Sand mining in Tamil Nadu

Sand mining, especially illegal sand mining in Tamil Nadu state is done on river beds, basins and beaches, It has been on an increase, since the beginning of the 1990s following a boom in the construction industry. Palar River basin, Vaigai River basin and Thamirabarani River basin are the major victims. Illegal quarrying is happening in these areas in broad daylight. Though as per Tamil Nadu Public Works Department, 5,500-6,000 truck loads of 200 cubic ft. of sand is mined each day, in reality the figure are estimated around 55,000 truckloads of 400 cubic ft. of sand per day. In 2013, illegal sand mining in the state was estimated to be worth . This also results in the state exchequer losing over in revenue.
Environmental impact.
Since river sand is a natural aquifer, its depletion also means recharging of groundwater, especially wells, fall. In January 2014, Union minister of state for Commerce and Industry, stated that due to sand mining in river beds, groundwater level or water table has dropped at an alarming rate, as a result some 18 lakh wells in the southern region have gone dry and water for agriculture purposes has become scarce. In Madurai, as per S Rethinavelu, senior president of CII, "Water table, which was at 50 ft or so, fell to 600 ft."
Response.
To curtail the rampant mining, in November 2013, Government of Tamil Nadu banned mining in 71 of the 90 sand quarries. Then in January 2014, the Union Ministry of Environment and Forests issued guidelines, according to which quarries with lease area of five to 25 hectares can only allow manual mining. However illegal sand mining is rampant according to newspaper reports and observation.