Offshore jobs are always difficult, but working in the dark and difficult waters of the Cook Inlet of Alaska present an even greater challenge. The area is notorious for up to 30-foot tidal swings and zero visibility water.

Operating from Global’s DSV Sand Island, divers performed an underwater survey of the spud cans on the Spartan 151 Jack-Up rig. Divers removed the well cap from the well head stub, then assisted in the installation of a overshot riser. Water velocity was measured using a Doppler Current Profiler, and bottom times were limited to just 30 – 45 minutes per tidal swing.