Application of Geoelectrical Method for Interpretation of Geohydrological Conditions around Rajahmundry, A.P.

Forty eight Geoelecti ical soundings (GES) were earned out on Alluvium (Al), sandstones of Rajahmundiy (RS) ot uppei Miocene, Tnupati (TS) of Juiassic and Deccan Tiaps (DT) of Eocene ages to delineate aquifeis around Rajahmundiy, East Godavaii Distnct GES show H,K,A and K A type representing three to four layered sub suitacelitho units Based on prehminaiy pump tests and lesistivity study, the aieacun bedemaicated into thiee groundwatet zones RS having 3 to 40 m thickness with lesistivity range of 2 6 to 63 Qm giving yield of 24000-1,13100 I ph. and aieas ot TS thickness 2 4 to 11 m with lesistivity range ot 3 3 to 57 Qm with yield of above 39600-49500 lph which are consideied as good potential zones The highly weathered DT, having thickness of 5 4 to 30 m with resistivity lange ot 1 32 to 10 Q.m have modeiate yield of 34000 38400 lph Based on the geoelectrical and hydiogeological studies ot the area ten sites weie recommended foi tube/boie well dulling with expected yield of 45420 68130 lph.