Assessment of groundwater potential zones in coal mining impacted hard-rock terrain of India by integrating geospatial and analytic hierarchy process (AHP) approach

Abstract

The study aims at delineating groundwater potential zones using geospatial technology and analytical hierarchy process (AHP) techniques in mining impacted hard rock terrain of Ramgarh and part of Hazaribagh districts, Jharkhand, India. Relevant thematic layers were prepared and assigned weight based on Saaty’s 9-point scale and normalized by eigenvector technique of AHP to identify groundwater prospect in the study area. The weighted linear combination method was applied to prepare the groundwater potential index in geographic information system. Final groundwater prospects were classified as excellent, very good, good, moderate, poor and very poor groundwater potential zones. Study thus revealed that the excellent, very good and good groundwater potential zones, respectively, cover 148.3, 373.66 and 438.86 km² of the study area, whereas the poor groundwater potential zone covers 180.05 km². Validation was done through a receiver operating characteristic curve, which indicated that AHP had good prediction accuracy (AUC = 75.45%).

Keywords:

• Groundwater potential index
• GIS
• remote sensing
• AHP
• hard rock terrain

Acknowledgements

The authors thank the anonymous referees for their suggestions for improvement of the manuscript. Authors are thankful to the Central Ground Water Board (CGWB) for providing weathered zone thickness data and to Indian Meteorological Department (IMD) and Directorate of Economics and Statistics (Department of Planning and Development), Ranchi for providing the rainfall data for the study area. The authors also express their sincere thanks to Sri Bimlendu Prasad (Junior Engineer), Drinking Water and Sanitation Department (DWSD), Ramgarh district, Jharkhand for providing the valuable information and suggestion regarding the groundwater condition of local area during this work. The first author acknowledges the financial assistance of the Institute fellowship provided by Birla Institute of Technology, Mesra, Ranchi to carry out the present research under Ph.D programme.