ABSTRACTA new simple and quick geophysical method for the siting of boreholes for hand‐pump supply in the crystalline rocks of Kano State, Nigeria has been developed. A single electromagnetic traverse with at least two depths of investigation is used to locate a potential subsurface feature which is then assessed by a vertical electrical sounding. Ground‐water quality has a significant influence on the data. The method and criteria for selecting a site are described in detail because careful site selection is important in reducing the time and money spent on unproductive drilling. In spite of generally unfavorable hydrogeological conditions in the crystalline rocks, 364 boreholes had acceptable rates of ground‐water production out of 429 sited using this m
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