Deformability characteristics of rock mass are one of the primary properties required for the design and safety analysis of dams, underground excavation/opening, foundation of civil engineering structures, etc. The Uniaxial Jacking Tests (UJT) are economical, reliable and easy to conduct for determining the deformability characteristics of the rock mass. The deformability characteristics behaviour is influenced by the size of the plate used for uniaxial jacking tests (UJT) as well as the applied stress imposed during the tests. Literature study shows that variation of deformability characteristics, i.e., deformation/loading modulus “Ed” and elastic/unloading modulus “Ee” is due to variation in the type of intact rock, discontinuities, rock mass condition, weathering, confinement and precision during site preparation, etc. The overall behaviour of rock masses depends on the origin and alteration process. The present paper deals with in-situ Uniaxial Jacking Tests (UJT) conducted on Quartzite rock mass at the right and left bank of the dam axis drifts at EL 935.36 m and EL 877.90 m, respectively, of Song Dam drinking water Project, Dehradun, Uttarakhand, with an accentuation on the locational inconsistency in deformability characteristics behaviour. Analysis and interpretation of deformability characteristics behaviour with respect to different test locations and elevations of rock mass is a complex assignment. An effort has been made to explain the same in this paper. Further, the influence of geological and terrain characteristics has been considered to explain the variation in deformability characteristics behaviour with respect to different test locations and elevations in detail.