Prospective techniques for in-situ treatment and protection of aquifers: A sustainable hydrology review

Most water table aquifers are polluted, yet they are the primary sources of urban and rural water supply. Sustainable hydrology in this millennium will capture in-situ treatment and protection of shallow aquifers particularly in developing countries. Permeable reactive barrier (PRB), biological and electrochemical methods with air and steam injection techniques will advance. Ex-situ pump and treat method is slow, costly and unsustainable. Many private treatment plants for pump-treat-use have been abandoned due to unsatisfactory output and operational problems. In-situ treatment of polluted aquifer starts with mapping pollution source(s), identifying stressors and migration pathway, estimating quantum of stress, and terminating release of stressors from the source. Sustainable hydrology shall also include developing hydrologic models code that can predict pollution, treatment method; amount and period of treatment. This shall be based on the characteristics of the aquifers; the pollution stress and the subsurface. Key words: Aquifer cleanup, permeable reactive barrier (PRB), biological, chemical, hydrodynamic model, sustainability.