Off Canada east coast, in the hostile, iceberg-infested North Atlantic Ocean, lies the Hibernia oilfield. Development and production of oil from this frontier area requires technological breakthroughs and innovations in engineering and construction.
Sitting on the ocean floor in 80 meters of water, 300 kilometers from land, the Hibernia oil production platform is like a concrete island with a unique saw-tooth form, which has the capability to withstand the potential impact of a six-million-tonne iceberg. No wonder Time magazine called it “one of the eight wonders of the modern world.”
Oil exploration in the Grand Banks of Newfoundland began in 1966. Several significant oil/gas discoveries have been made since then and Hibernia is the lead production project in pioneering this offshore frontier. The field was discovered in 1979 with the drilling of an exploration well. Between 1980 and 1984, nine wells delineated the extent of the field. In the fall of 1990, the Hibernia owners and the federal and provincial governments of Canada concluded legal and financial agreements to allow the development project to proceed. Mobil, Chevron, Petro-Canada, Murphy, and the government of Canada own the oil asset. In 1990 they formed the Hibernia Management and Development Company (HMDC) to manage, develop and operate the Hibernia offshore oilfield asset. The engineering, procurement and construction cycle then commenced.
The Topsides for the Hibernia offshore oil drilling and production platform, on the assembly Pier at the Bull Arm construction site in Trinity Bay, Newfoundland.
Photo by Hibernia Management and Development Co. Ltd.
Scope
The production system, which will be ready for operation by late 1997, includes a fixed production platform, a crude oil loading system and shuttle tankers. The platform consists of a massive concrete Gravity Base Structure (GBS), which stores produced oil and supports the Topsides Facilities (drilling, production, utility systems and personnel accommodations). The crude oil system includes offshore subsea pipelines and an offshore loading system to transfer oil from the production platform to tankers.
The completed platform will have an on-bottom weight at the offshore site of more than 600,000 tonnes. The gross weight of the concrete structure, including solid ballast and stored fluids (sea water/crude oil) exceeds one million tonnes. The platform will have sufficient capacity for the storage of over one million barrels of oil.
The cylindrical part (caisson) of the GBS is 106 meters in diameter and 85 meters high. It is composed of ice wall and supporting walls, oil containment and partition walls and four shafts. The four shafts—two drilling, one riser, one utility—extend above the GBS to a height of 111 meters and support the Topsides Facilities. The GBS is constructed of high-strength concrete, reinforced with 90,000 tonnes of steel rods (rebar) and 8,000 tonnes of cables (prestress).
The Topsides Facilities have a design capacity of 150,000 barrels of oil production per day. The average peak production of 135,000 barrels/day is expected to occur over a seven-year period from the year 2000 to 2006. By the turn of the century, Hibernia will be providing about 10 percent of Canada's total oil production. Total full life cycle costs are estimated at $16 billion Canadian, of which $8.5 billion is for capital expenditures and $7.5 billion for operating costs. The project development costs up to first oil in 1997 are estimated at $5.8 billion (part of the $8.5 billion). The Hibernia Project breaks even at an average oil price of $13.65 per barrel (constant 1992 U.S. dollars) over the 19-year producing life of the oil field.
The loading and transportation system will include two pipelines connecting the production platform to the Offshore Loading System (OLS). The OLS will have a capacity to transfer 52,000 barrels of oil per hour from the platform to tankers. Several double-hulled, ice-strengthened tankers of about 120,000 tonnes deadweight will be employed. Each will have a cargo capacity of about 850,000 barrels of oil.
The platform can accommodate 280 personnel in its living quarters and generate electrical power equivalent to the electrical supply for a town of 40,000 inhabitants.
The project development has a duration of about seven years, from its start in 1990. In late 1997, the engineering, procurement, construction and commissioning cycle will be complete; first oil will be produced, and the platform and facilities will be handed over to the producing operation's organization to continue oil production for about a 19-year period, ending in the year 2016.
Engineering Innovation
The latest technology was maximized for the Topsides engineering. A major 3-D CAD model of the Topsides design, one of the largest 3-D models ever produced, was employed to ensure that a clash-free design existed. To suit the project's specific requirements, existing commercially available software was modified. Over 100 engineering personnel were trained in a three-stage CAD enhancement program.
Platform Topsides for GBS-type platforms in the North Sea have typically been designed and constructed using a Module Support Frame (MSF) with small pre-assembled modules placed on top of the MSF. By contrast, Hibernia Topsides is the first of a new generation of GBS platforms utilizing the super-module concept. Replacing the need for a MSF, the five Hibernia super-modules were designed as integral primary structures of the platform's Topsides.
The main advantages of this design concept are shorter hook-up periods at the at-shore assembly phase, and a commissioning program maximized onshore. The super-module concept also allowed Hibernia to take advantage of modern control systems technology to achieve the goal of safe, cost-effective control system design, with local electrical and instrument rooms distributed to each super-module.
Using a Computer Integrated Enterprise (CIE) approach, the following platform systems have been integrated: process control; fire and gas detection and protection; emergency shut-down; electrical power management; heating, ventilation and air conditioning; drilling; and engineering/management information systems.
The central control room is the hub of all platform production-related activity. Here the operator monitors and controls the various systems using only one screen/keyboard display format for all systems. In this approach, the control room operators take on an added responsibility. To ensure that the operators are completely familiar with the platform's systems, great attention has been paid to training. An exact replica of the platform control room has been built as a training simulator. Every system on the platform will be replicated to train and test operator response using one of the most comprehensive training simulators in the world.
The GBS has been equipped with structural and foundation monitoring instrumentation to record loadings on structure and seabed during storms. By this means, design verification can be achieved and safety confirmed.
Drilling
About 80 wells will be required to produce the oil and re-inject water and produced gas. The latest drilling technology will be used and will include lateral drilling techniques to permit an area within an 8,000-meter radius from the platform to be exploited. Maximum vertical depth of the wells will be 3,700 meters and measured well depths of greater than 8,500 meters with angles greater than 75° will be possible.
The drilling program spans a ten-year period from 1997 to 2007. Two drilling rigs are mounted on the Topsides wellhead module and will drill through two of the four concrete shafts. Each rig can be skidded east/west with a skid base and north/south with a substructure using a hydraulic jack and gripper system. The rest of the heavy drilling facilities (i.e., drilling mud pumps, cementing system, bulk storage tanks and electrical SCRs and transformers) are located as low as possible in the Topsides to optimize platform stability during tow to the offshore site.
Loss Management
One of the principal goals of the Hibernia project is to ensure that oil production facilities are built and operated with a minimal impact on the environment, local communities, and other marine users such as the fishing industry.
To achieve these goals, project managers, with the support and encouragement of the owners, have adopted or developed “best in industry” standards and practices with respect to loss management programs. Compliance with all current regulations is a given; in some cases a “beyond compliance” approach has been adopted where there are compelling business or project needs.
The owners have conducted extensive environmental research and analyses to establish the required understanding of the effects of the environment on the project (the physical environment) and the impact of the project on the environment (the biological environment).
Starting at the design stage, teams of environmental, loss prevention and quality professionals were engaged to advise the organization in incorporating the required principles into the engineering, construction and operations phases. During this stage, a project-specific risk assessment (Environmental Review Using Structural Analysis Techniques) was developed and implemented to ensure that the platform design met or exceeded all regulatory requirements for offshore waste treatment.
The development of a new construction site at Bull Arm, Newfoundland, was supported by an Environmental Protection Plan that gave direction with respect to acceptable practices during site development and construction of the GBS and Topsides. In consultation with the fishing industry, local communities and governmental departments, initiatives have been taken to avoid or to minimize the impacts (such as sedimentation) associated with dredging, blasting and construction activities that may concern other local marine users.
A contractor safety/environmental evaluation program was used by Hibernia as part of its contracting strategy to ensure that only those contractors with integrated loss management programs (and evidence of acceptable performance) were considered for the major contracts on the Hibernia project.
Construction of the Gravity Base Structure in the Deep Water Site at Bull Arm. The shafts are now at a height of 106.2 meters.
Photo by Hibernia Management and Development Co. Ltd.
Prevention and monitoring programs are an integral part of the construction activities at Bull Arm, with special emphasis on water quality, spills, beach litter. Eagle/osprey nesting and hatching success is monitored, together with recording any sightings of oiled birds. Testing was conducted to determine if there was any impact on whales arising from blasting or the dumping of dredge spoils associated with the construction and removal of the dry dock berm.
In anticipation of the transition from a construction project to producing operations, HMDC has developed an integrated loss management system. The Environment, Safety and Quality Assurance (ESQA) system was incorporated into the overall management system of Hibernia in late 1995. Following this is the integration of the loss management programs of the primary contractors associated with production, drilling and transportation/ logistics activities prior to installation and commissioning.
An Operational Plan will be put in place to address, among other project and regulatory requirements, the need for an Environmental Protection Plan and a Safety Plan.
A pre-production baseline survey has been conducted to establish levels of contaminants in the area of the platform. As described in an Environmental Protection Plan, continual monitoring of the seabed and marine life after production starts will identify any changes in the contaminant level.
A contractor safety environmental evaluation program is utilized by Hibernia as part of its contract strategy to ensure that only environmentally conscious contractors are considered for work on the Hibernia Project.
Platform Evacuation Systems
Because the Hibernia platform will initially be a lone facility situated in a rough environment some 300 kilometers from land, considerable contingency provisions are built into the design to provide a safe escape in the unlikely event that platform evacuation is required. While helicopter service will be utilized throughout the operations phase for crew changes, predominant fog conditions in the area significantly limit helicopter reliability for emergency evacuation situations.
A suite of three systems will be utilized for platform evacuation:
Dry Transfer (GEMEVAC Gondola Transfer System) consists of a 16-person gondola which transfers personnel from the platform to the deck of a platform supply vessel. The gondola operates on a hydraulics/wire system connected between the platform and ship.
Semi-Wet Transfer (Lifeboats with PrOD Launch Assist) is a system composed of lifeboats with a launching device called a Preferred Orientation and Displacement (PrOD). The PrOD is a long glass-reinforced plastic boom oriented perpendicular to the side of the platform with a wire attached to the bow of the lifeboat. As the lifeboat is lowered to the sea the PrOD boom flexes and provides a force on the bow to ensure that it enters the sea pointed away from the platform. Then the lifeboat drives off.
Wet Transfer (Selantic Skyscape System) is used as a backup system to the preferred evacuation systems. This wet transfer system enables platform personnel in survival suits to reach the sea surface in a controlled manner. The Selantic Skyscape Evacuation Chute contains four, 25-person life rafts and a base raft that are lowered to the sea. Access to the base raft is by a woven kevlar tube. Upon sliding down the chute to the sea surface, personnel board the life rafts tethered at the end of the chute.
Quality
While engineering plans and project schedules represent two key types of project documents, there is a third equally important type of plan referred to as the Project Quality Plan. This plan established a quality policy for the project and defines responsibilities and activities for planning, achieving, and assuring the quality functions. The Project Quality Plan may be thought of as a “road map” for achieving quality results.
For Hibernia, the Project Quality Plan has been prepared in accordance with Canadian Standards Association (CSA) CAN 3 Z299 Quality Assurance Program Standards. CSA Z299 QA standards are required by Canada/Newfoundland Offshore Installation Regulations.
CSA Z299 is a series of QA standards of varying levels of comprehensiveness. CSA Z299.1 is the most comprehensive and is focused on preventing non-conformance from occurring through activities such as design planning, management review, and internal QA audits. The next standard in the series, CSA Z299.2, is less comprehensive than Z299.1 and is focused on reacting to non-conformances to ensure they are not repeated through activities such as design verification and corrective action. The last two standards, CSA Z299.3 and Z299.4, are focused on verifying and sorting functions, respectively, and are each less comprehensive than the standard preceding it.
The selection of a specific QA program level for a particular platform system, component, or structure, is based on a criticality rating that considers criteria such as design complexity and maturity, production capability, safety, and economics. The higher the criticality rating, the more comprehensive is the QA program standard selected. The Hibernia Project provides a good example of how the QA program selection process works.
The Hibernia GBS and Topsides structure, including drilling production and accommodations facilities, are being designed and built in accordance with a QA program that meets the requirement of CSA Z299.1. The most comprehensive QA program level was selected for these activities after a criticality analysis confirmed that the design effort was novel and complex, the construction and assembly of the platform was unique, and the environmental, safety, and economic impact of loss was enormous.
While the overall QA program level selected for the Hibernia Project is Z299.1, individual components and structures within the project may be produced to a less comprehensive QA level, provided a criticality analysis justifies the selection. For example: pressure vessels and process piping have been assigned a Z299.3 QA level because these components, while critical to safe platform operations, are generally designed and built to existing standards and proven manufacturing methods. In much the same manner, individual Topsides modules are being fabricated and outfitted in accordance with QA programs that meet Z299.2 requirements. A Z299.2 QA program was selected for module fabrication due to the similarity of existing fabrication processes and assembly methods.
The ability to select different levels of quality assurance for different types of structures, equipment and materials is a major strength of the CSA Z299 QA standards. By judiciously selecting the appropriate QA level, a facility that is “fit for purpose” is ensured.
While CSA Z299 QA standards are required by Canada/Newfoundland Offshore Regulations, provisions do exist to permit the use of other quality standards, provided an equivalency evaluation is conducted to confirm the standards are comparable.
For example, many Hibernia suppliers maintain quality systems that comply with ISO 9000 standards. The ISO standard has been adopted on a case-by-case basis, provided the supplier agrees to include CSA Z299 QA requirements in the Hibernia order. Additional CSA Z299 QA requirements may include topics such as external quality audits of subsuppliers and independent inspection, witnessing and monitoring.
Certification
Canada/Newfoundland Offshore Regulations require that an offshore operator obtain a valid Certificate of Fitness as part of the application for a Production Operations Authorization. This means an offshore installation must be certified as “fit for purpose” before an operator can produce hydrocarbons.
A Certificate of Fitness is a document issued by a Certifying Authority (CA), certifying that an offshore installation has been designed and built in accordance with applicable regulations and is “fit for purpose.”
The term Certifying Authority refers to an independent third party authorized by the regulatory authority to issue a Certificate of Fitness. The certifying authority for Hibernia is Lloyd's Register of Shipping.
The offshore certification scheme requires that the certifying authority performs a design appraisal of critical platform structures, systems, and components and provides surveillance of critical manufacturing activities. The results of the design appraisal and survey are the basis upon which the Certificate of Fitness is issued.
Hibernia has structured the CA scope of work to take into consideration the comprehensive QA plan prepared for the Hibernia Project. In effect, a portion of the certification activity has been shifted to the project. The CA accomplishes its certification objectives by performing a continuous critical evaluation of the Hibernia QA plan through periodic selective monitoring. Hibernia believes that a comprehensive QA plan, which is aggressively implemented by the project team and monitored by the certifying authority, is the proper balance to ensure world-class results.
Challenges
Unique megaprojects usually face many hurdles and Hibernia is no exception. While Canada has a long and successful history in the oil and gas industry in Western Canada and in the Arctic, there is a shortage of expertise in the engineering and construction of large offshore platforms. Additionally, no onshore infrastructure existed in Newfoundland to construct a large platform of this type.
The owners' Development Plan called for a very significant level of Canadian content, and the project has delivered well in excess of its commitments. By late 1995, about two-thirds of the expenditures had occurred in Canada, and 5,500 of the 8,000 persons employed on the project were Canadians.
The biggest challenge was the creation of the new construction site at Bull Arm, located 130 kilometers from Newfoundland's capital, St. John's. Clearing of the woods and civil works commenced in late 1990. A year later, Hibernia had excavated two million cubic meters of rock, built 14 kilometers of roads, and installed living accommodations for over 3,000 people. Full amenities were provided for the labor force, including a bank, library, general store, cable TV station, newspaper, gym, swimming pool, bar, and a dining room that seats 1,000.
Construction infrastructure served both Topsides and GBS construction activities, The GBS base commenced construction in a dry dock of 40,000 m2 and 18 meters in depth, with a berm built to hold back the waters of Trinity Bay. GBS construction began after the dry dock civil works was ready in 1992. In late 1994, the dry dock was flooded, the berm removed and the 120,000-tonne base section floated out to a deep-water sheltered location about 3 kilometers away. Slipforming (a continuous concrete pour technique) continued at the deep-water site bringing the massive caisson up to its roof level of 85 meters. This work continued despite the subzero temperatures of Canada's winters, complete with snowstorms, freezing rain and power supply outages.
The Topsides Facilities were designed in five modular components (super-modules) and a number of smaller Topsides Mounted Structures (TMS), totaling 37,000 tonnes. One of the super-modules, the M20 wellhead module, and some TMS were built in a purpose-designed fabrication yard at Bull Arm. The other four super-modules were built in Italy and Korea.
Each super-module is designed to have all its systems and components largely self-contained within the module to permit a maximum level of mechanical completion and commissioning to be completed onshore, as offshore construction labor activities are prohibitively expensive. Each super-module is a structural entity; the largest is 7,800 tonnes.
The four overseas modules were each transported on a very large transport ship, delivered to the construction pier at Bull Arm at two week intervals. In the spring of 1995, all five modules arrived and work to connect them commenced. The Topsides interconnection and final commissioning will be completed by November 1996.
In the spring of 1997, the total Topsides will be floated over the finished GBS and mated at the deep-water site. Final platform hook-up and commissioning work will be completed prior to the platform tow-out to the Hibernia site in the summer of 1997. On location, the platform will be lowered to the sea floor, grouted and loaded with solid ballast. Drilling will then commence and first oil production should be achieved by the end of 1997. ▄
James A. Ferrier, PMP, was site manager for the construction, mechanical completion and commissioning of Topsides facilities, Modules M30 and M40. He was on assignment to HMDC from Petro-Canada.
Henk C. van Zante is construction general manager for the Hibernia project and is responsible for Hibernia Topsides and GBS construction and all marine activities. He is on assignment to HMDC from Mobil Oil.
David Luther is GBS engineering manager for the Hibernia project. He is also on assignment to the HMDC from Mobil Oil.