Enhanced Enterprise-Class Drillship

Transocean announced that Chevron Corporation has awarded the company a contract for the construction of an enhanced Enterprise-class drillship. The enhanced Enterprise-class drillship, to be named the Discoverer Clear Leader, is being designed to include the most advanced drilling capabilities in the offshore drilling industry, building on Transocean's successful Enterprise-class drillship design. Chevron has awarded the company a five-year contract, which is expected to commence during the second quarter of 2009, after an estimated 30-month shipyard construction phase, followed by sea trials, mobilization to the U.S. Gulf of Mexico and customer acceptance.

Construction of the dynamically positioned, double-hull drillship Discoverer Clear Leader is scheduled to take place at the Daewoo Shipbuilding and Marine Engineering yard in Okpo, South Korea, with an estimated total capital expenditure of approximately $650 million. The Discoverer Clear Leader will feature Transocean's patented dual-activity drilling technology, allowing for parallel drilling operations designed to save time and money in deepwater well construction, compared with conventional rigs. The dual-activity technology, along with a new and enhanced top drive system, an expanded high-pressure mud-pump system, expanded completions capabilities and other unique features of the drillship target the drilling of wells up to 40,000 feet of total depth. The rig will have a variable deckload of more than 20,000 metric tons and will be capable of drilling in water depths of up to 12,000 feet. The Discoverer Clear Leader will be an enhanced version of Transocean's three predecessor Enterprise-class drillships, which have set deepwater drilling records in recent years, including the world water-depth drilling record of 10,011 feet held by the Discoverer Deep Seas (see picture).