भूजल गुणवत्ता

Under NAQUIM, arsenic safe exploratory wells have been constructed in arsenic affected parts of the States of West Bengal, Bihar and Uttar Pradesh. The arsenic safe deeper aquifer zones have been identified and wells have been constructed tapping the arsenic safe deeper aquifers using innovative cement sealing technique. So far, 513 exploratory wells tapping arsenic safe aquifers have been constructed under NAQUIM programme including 40 in Bihar, 188 in West Bengal and 285 in Uttar Pradesh. The innovative cement sealing technique of CGWB has been shared with the state agencies to utilize to construct arsenic free wells. The technique is most effective in the alluvial terrains in parts of Bihar, Uttar Pradesh and West Bengal where hydrogeological conditions favour construction of such wells. Successful implementation of the technique requires domain expertise in identifying and locating suitable clay zones that separate arsenic safe aquifers from the contaminated ones so that cement sealing can be placed against these impervious zones. The State Water Supply Agencies of Uttar Pradesh and West Bengal have applied the cement sealing technique. States of Uttar Pradesh and West Bengal have constructed nearly 1450 such wells catering to the drinking water requirements of nearly 70 lakh persons.