Abstract:  Geotechnical investigations in the mountain terrains should thoroughly inspect the environmental geology conditions in surrounding areas. Layered groundwater observations might be necessary for areas that the artisan groundwater levels are suspected. As a case history, this paper presents that, in the castinplace concrete pile installation site, large quantities of groundwater were gushing into the boreholes. The groundwater gushing mechanism was investigated, and cost effective mitigation measures were provided.

Key words: Mountain Terrains, Pile Installation, Groundwater Gushing