Pioneering Offshore Excellence

Abstract

Introduction Hibernia Management and Development Company Ltd. (HMDC) was formed in 1990 by a consortium of oil companies to develop their interests in the Hibernia and Avalon reservoirs offshore Newfoundland in a safe and environmentally responsible manner. The reservoirs are located 315km ESE of St. John's in the North Atlantic [see Fig 1]. The water depth is about 80m. The entire Hibernia field is estimated to contain more than three billion barrels of oil in place and the owners' development plan area is estimated to contain two billion barrels. Recoverable reserves are estimated to be approximately 615 million barrels. The Hibernia reservoir, the principle reservoir, is located at an average depth of 3,700m. HMDC is building a large concrete gravity based structure (GBS) that which will support the platform drilling and processing facilities and living quarters for 280 personnel. In 1997 the platform will be towed to the production site and production will commence late 1997. Oil will be exported by a 2 km long pipeline to an offshore loading system. Dynamically positioned tankers will then take the oil to market. Average daily production is expected to plateau between 125,000 and 135,000 BOPD. It will be the first major development on the east coast of Canada and is located in an area that is prone to pack ice and icebergs. In order to provide for the safety of people, to limit the impact on the environment, and to protect the facility, HMDC employs three strategies: Platform design that integrates safety and environmental considerations. Environment and safety issues are dealt with early in the design process, preventing (or at least reducing) the possibility of an acute or chronic safety or environmental issue. Using this approach, an inherently environmentally sound and safe design has been developed. An example of this approach is the risk analysis and assessment carried out during the design phase. Systems or ways of working that prevent or reduce the impact of an incident. Examples of this strategy include the development of safety, environmental, and quality management systems based on standards such as ISO 9000 and 14000. Finally, safety and environmental equipment that reduces or mitigates the impact of an incident once it occurs. Examples include readily available evacuation equipment and oil spill response equipment. Site Environmental Conditions The physical environment of the Hibernia location is a demanding one. The Hibernia platform will be located near the northeast corner of the Grand Banks. To the north and east of Hibernia the water depth increases rapidly to more than 1,000m at the Flemish Pass, which separates the Grand Banks from the Flemish Cap, a bank to the east of the Grand Banks with water depths as shallow as 140m. The Labrador Current, the major current in the Hibernia area, is from the north. The presence of the Grand Banks/Flemish Cap splits the flow of the Labrador Current into two main branches. The inner branch flows south along the coast of Newfoundland while the outer branch flows along the north slope of the Grand Banks before turning south through Flemish Pass. The Hibernia site is situated between these two current streams in shallower water, away from the strongest currents and deepest water. The Labrador current carries sea ice and icebergs into the Hibernia area. [See Fig. 2] The International Ice Patrol (IIP) has monitored the number of icebergs crossing 48 N Latitude, the location of the Hibernia reservoir, since shortly after the sinking of the S.S. Titanic in March 1912. The number of icebergs that have crossed 48 N each year since 1946 is highly variable. For example, in 1984 more than 2,200 icebergs drifted south of 48 N, whereas in 1977, only 22 icebergs were sighted south of 48 N. More recent data from IIP, based on side-looking radar surveillance, shows that this variability continues with 876 icebergs reported south of 48 N in 1992 and almost twice that number, 1753, in 1993. P. 385