Dwarfing all neighboring construction projects in Texas' Ingleside shipyard complex, and swarming with more than 750 workers, BP's Thunder Horse floating PDQ facility is readying for a first-quarter 2005 sailaway. The semisubmersible's home for the next 25 years or so will be in 6,050 ft (1,982 m) of water in Mississippi Canyon Block 778/882, about 150 miles (241 km) southeast of the mouth of the Mississippi River. It will be moored there by a 16-point pre-set spread of wire/chain mooring lines.
With a displacement of 130,000 short tons, Thunder Horse is 50% larger than the next biggest similar unit. In operation, it will handle 250,000 bo/d, 200 MMcfg/d and 140,000 bw/d, and has the pump capacity to simultaneously process and inject up to 300,000 bw/d of injection water at 6,000 psi or 200,000 bw/d at 8,000 psi.
Operated by BP with a 75% interest, Thunder Horse's remaining 25% is owned by ExxonMobil. The facility will tie-in to the Mardi Gras subsea pipeline network that links with production from Holstein, Mad Dog and Atlantis when it comes ashore at Grand Isle, La., and also to a gas pipeline spur from the giant Na Kika gathering system ultimately making landfall in Pascagoula, Mississippi. Thunder Horse, which comprises two adjacent fields, was discovered in 1999 and consists of Upper Miocene turbidite sandstone reservoirs.
Following an 18,000-mile (28,962-km) sea transit aboard Dockwise's Blue Marlin heavy-lift transport vessel from the Daewoo shipyard in Okpo, South Korea, Thunder Horse's hull was tied up alongside Peter Kiewit's Ingleside facility for final assembly. With three modular topsides units manufactured at J. Ray McDermott's Morgan City, La., yard and transported to Texas on a custom-built 400-ft by 126-ft (122-m by 38-m) barge, Thunder Horse's final assembly and commissioning is proceeding on plan, according to Mike Baur, BP facilities manager. The production and compression topsides modules have already been installed and the 90 MW power generation module will be in place before the end of October. A new dual derrick drilling unit was installed in Korea and will be operated by Pride International. Although several wells in the field have been pre-drilled and cased using Transocean's Discoverer Enterprise drillship, the unit's own rig will drill additional development wells as the field is brought onstream. FMC will supply a network of 25 subsea trees, flowlines and manifolds. First oil is expected during the second half of 2005.
One sound not heard to date is the sound of sirens. The project boasts an enviable safety record - 6.5 million man-hours with only three lost time accidents (LTA) in Korea, and 4.0 million man-hours with zero LTA's in Morgan City. The Ingleside phase is expected to require about 500,000 man-hours to complete. Beside its safety record during the construction phase, Thunder Horse is designed for safety at sea. It can withstand winds to 165 kts and 92-ft (28-m) seas.
Thunder Horse is the latest in a long line of nearly two dozen Gulf of Mexico fields operated by BP. The product of an aggressive exploration strategy, the concurrent development of these fields has proceeded at a pace that is unprecedented in our industry.