The Council for Geoscience (CGS) invites potential suppliers to provide quotations for the drilling of a deep (600m) groundwater monitoring borehole. Specifications: • 0-~15m: Drill with 381mm (15”) for starter casing; • ~15 m to ~250m: Drill with 305mm (12”), install solid steel casing (10”) then grout from 200 to 250m • ~200 m to ~350m: Drill with 215m (8.5”) then install µPVC casing (7”); • ~350m to ~E.O.H: Drill with 165m (6.5”); • Aquifer testing 4 x 1 hour step test and recovery and 72 hours constant discharge and recovery. (投標 №95029858cn)