Intecsea survey of Arctic offshore well control and containment equipment, best available technologies and practices

On this page

• Executive summary
• Key findings
• Key recommendations
• Data gaps
• Closing remarks

Executive summary

This survey was commissioned to contribute current and prospective information on well control and containment equipment, best available technologies, and practices, and their appropriateness for deployment in Canada's Arctic waters. The knowledge contained within this report is meant to inform interested parties, including those responsible for decision making around the moratorium and about petroleum management in the Arctic offshore in general.

For clarity, well control refers to techniques used to maintain pressure in the wellbore, to control, to prevent, or mitigate the flow of formation fluids into the wellbore (after National Energy Board [NEB], 2011). Well containment, more comprehensively defined in the industry as well source control and containment, is a generic term for all activities related to the direct intervention of a well that has experienced a loss of well control, with the intent to halt or control the release of hydrocarbons to the environment.

Operations in remote areas are not new to the oil and gas industry. However, in addition to the usual problems associated with remote operations, Canada's Arctic offshore is confronted with:

• extreme cold
• winds
• waves
• sea ice (up to 8/9 months of the year)
• a closed operating environment restricting supply access and operations
• lack of infrastructure
• reduced daylight hours during the winter
• a not well-known geological province
• unique environmental issues
• stringent government regulations
• complex geopolitical climate

Regardless, the Arctic is not a region where a company can "learn by failing", but a place where all major risks must be understood, managed and controlled.

The development of equipment, technology, and practices, and its implementation play a key role in the safe exploration and development of oil and gas worldwide. Breakthrough improvements have been made across the board. The ability to predict the downhole environment has also improved significantly. Much of this progress accelerated after the 2009 Montara blowout in Australia and the 2010 Deepwater Horizon blowout in the U.S. Gulf of Mexico (Macondo), seeding the development of the offshore well source control and containment industry. In fact, current well design and construction methods are significantly safer than in 2006 when the last Arctic offshore well was drilled in Canada and cannot be compared to the earlier exploration wave between 1970 and 1990 where 91 wells were drilled.

A precept of this report is that the industry can operate safely, responsibly, and consistently, even if it has not always been the case. It also assumes that Arctic exploration will use the best available technologies and practices. However, the petroleum industry involves risky and hazardous operations, and several critical processes still depend on human barriers, requiring a highly reliable system and an organization committed and continuously compliant to safety and integrity.

Experience is another critical factor. At the time of this survey most experienced personnel in the region were already retired, or on the verge of retirement. With lower levels of activity in Arctic drilling, there has been a very limited knowledge transfer. As there are very few places elsewhere that can be compared to Canada's Arctic offshore, any future oil and gas exploration will need to undergo a steep learning curve. The learnings may be facilitated given that drilling technologies are essentially the same as in other parts of the world, and that some of the industry developments that are not Arctic-rated can be reengineered to be deployed, if required.

This survey represents a thorough analysis of the barriers to preventing and mitigating a loss of well control scenario, which should support informed decision-making regarding well control and containment requirements in Canada's Arctic waters, and beyond. It is focused on exploration drilling of conventional offshore oil and gas resources. Development is not discussed as it would be meaningless if the cost for exploration drilling is too high, or business risks judged to be too great.

Inevitably, a number of cascading failures would have to happen for a blowout to occur during well construction operations. These will likely involve both failures of human decision-making and of safety equipment/physical barriers. This survey did not dwell further on the human factors, competency, and training necessary to manage and control risks. It is sufficient to note that well control and containment relies on personnel and that human factors need to be seriously considered for any project in Canada's Arctic offshore.

Regardless of the reader's experience, the report will add value to anyone willing to understand the challenges, equipment, best available technologies, and practices for well control and containment, with an added emphasis on the Arctic region. The following subjects, thoroughly discussed in this report, are critical to minimize or mitigate a loss of well control:

1. well design and construction
2. pore pressure and fracture gradient prediction
3. drilling fluid pressure management
4. kick prediction and kick detection
5. downhole isolation
6. sub-surface (mudline) isolation devices (SSIDs)
7. blowout prevention
8. source control and containment
9. relief well drilling

Key findings

Technology, by its very nature, is always evolving. It is evident that breakthrough improvements have been witnessed in:

• manufacturing
• communications
• regulations
• availability
• reliability
• redundancy
• automation
• analytics

Many of these improvements are discussed on this report.

The performance-based Same Season Relief Well (SSRW) Equivalency concept hinges on the interpretation of the SSRW Policy. Ever since it was issued in 1976, the Policy has been widely interpreted as the need for a continuous relief well operation that can be completed, and both wells safely killed and suspended before ice conditions preclude any further operation. The industry argues that the SSRW Policy does not focus on prevention and that faster means exists to bring a well under control. The industry also contends that the capability to drill a relief well in the same season should be instead replaced with specifying the desired outcome: to stop the flow of a well at the earliest opportunity. However, the Policy itself was enacted as a "response to a failure to prevent". The regulations and the regulators expect prevention as a basic principle.

The current SSRW Equivalency solutions are designed to promptly stop the formation flow just above the wellhead using a pre-installed sealing device (for example a blowout preventer [BOP] or a subsurface isolation device [SSID]), so that conventional kill procedures can be undertaken to re-establish the primary well barrier and bring back the well to static conditions. If a well is shut-in before a blowout occurs, regaining control of the well could be achieved with the same drilling unit. If the kick escalates to a blowout or if the rig needs to be demobilized due to metocean conditions, the pre-installed sealing device and all the exposed well barrier elements need to contain the pressure until well intervention can be safely undertaken in the following drilling season, which may, or may not, include the drilling of a relief well with a different rig. A capping stack is another sealing device that could be used with the same purpose.

This approach does not preclude the use of relief wells as part of the source control and containment toolkit. As SSIDs and containment solutions can be used in addition to drilling a relief well, opposing stakeholders to the industry's SSRW Equivalency argue that the available equipment, technologies, and practices do not meet the prescriptive requirement of drilling a relief well and killing a blown-out well during the same operational season. Hence, it has not been possible to settle the SSRW Equivalency argument, and a clearer interpretation of the policy may be required for all the stakeholders looking after oil and gas exploration in Canada's Arctic offshore.

More to the point on SSIDs: there was no documented case of an SSID being used to manage an influx or a loss of well control simply because it has not been needed. This contributes to the argument that the industry is able to safely operate with conventional barriers and that the presence of an SSID minimizes the risk of event escalation. At the same time, it also means that the effectiveness of SSIDs has not been completely tested under loading, even if these devices are manufactured with field proven or qualified components and assemblies. Moreover, the majority of available shear and seal rams cannot shear everything (for example tool joints, drill collars, and other traditional nonshearables). Only one solution provided by Kinetic Pressure Control appears to have overcome the historical limitations of closure devices to shear and seal.

On the other hand, if an SSID is activated and the drilling rig is disabled or needs to be demobilized without killing the well, the pressure will need to be contained by all the exposed well barrier elements until the next drilling season. This means that a formation fluid influx will be left unattended and with limited means of monitoring for an extended period. Besides the effect of gas migration below the wellhead and the consequent higher pressures in the open hole, this unproven practice will rely on a single well barrier that is exposed to a continuous load.

Finally, there are areas in Canada's Arctic waters where the drilling of a relief well in the same season would be highly challenged, and in many cases, impractical. This is the case in the promising hydrocarbon potential areas of the Shelf Edge and Slope of the Beaufort Sea where a normal well may require multiple seasons to be completed. In these areas, there is a combination of deeper, more complex wells within a shorter open water season and the added presence of multi-year ice.

Key recommendations

The SSRW Policy has been consistently upheld by the government authorities as an important regulatory component for the protection of the Arctic marine environment. Over time, its interpretation has been blurred by various factors, including:

• rapid ice melting
• technology developments
• competing interests of the various stakeholders
• public perception
• geopolitics

There is also a precedent from 2003 where the NEB considered that an SSID was a viable solution for SSRW Equivalency in preparation for Devon's drilling campaign in 2006. While understandably SSRW Equivalency is an open concept within the goal-setting framework, it has reached a point where the supporting and opposing parties will not agree on further Arctic oil and gas exploration due to its history, different understanding, and interpretation. Regardless of the moratorium decision, consideration should be given to clarifying the concept on a public hearing process on SSRW Equivalency and/or to framing the SSRW Policy as a goal setting requirement.

The use of an SSID minimize the risks of major event escalation. An independently configured SSID located above the wellhead and below the rig's BOP provides several benefits. However, the use of this device does not kill a well near the reservoir and requires that all barrier elements containing the pressure work reliably, including any exposed open hole formation. The discussion on SSRW Equivalency may be different if a downhole BOP can be installed closer to the reservoir: sealing a wellbore near the reservoir may be comparable to the SSRW Policy goal. Nonetheless, at the time of this survey, there was no commercial device able to seal a flowing well from the bottom and with pipe in the hole, even if this concept had been previously explored.

For instance, Exponent (backed by Shell) had devised a promising solution that could be installed downhole just above the reservoir. The tool, known as the well restriction tool (WRT), has the potential to shut-in an out of control well in the in the unlikely event that all other barriers fail. The shut-in will be near the reservoir unlike secondary or tertiary well control barriers like the BOP, SSIDs, or a capping stack. This concept could be a step change in well control, which may question the premises of the SSRW Policy, as a reliable and redundant system of downhole isolation barriers could promptly shut-in a blowout. However, the development of the tool was halted in 2015/2016 due to the oil price slump. Further research is required to guarantee reliability, integrity, redundancy, sealability, failsafe, and other attributes needed to qualify it as a well barrier element.

The implementation of suitable barriers improves the system reliability. This became evident with U.S. NASA's analysis of Kinetic Pressure Control's closure device discussed in Section 3.6. The actual reliability improvement is significantly better when suitable equipment, best available technologies, and good practices are implemented in the well design and construction. The regulators, the industry, and/or an applicant wishing to drill in Canada's Arctic waters should consider performing a probabilistic risk assessment (PRA) to understand how each, and all of the applicable solutions to be deployed affect the well system reliability against a loss of well control. Independent verification and well examination schemes could improve the overall reliability.

Finally, shearing and sealing is a critical feature in today's BOP systems. Even if the technology has improved significantly in the last 10 years, the majority of the closure device systems cannot shear all tubulars that may be used during the well construction. The regulators should encourage, and the industry should consider accelerating the development of devices that overcome the deficiencies of current shear ram technology and enabling a real failsafe device. This can make oil and gas exploration and development a safer industry.

Data Gaps

The survey was limited by the lack of participation of critical stakeholder groups, particularly exploration and production operators. It became evident that for most companies, the investment in Arctic development had been halted after the drilling moratorium was enacted in late 2016. None had available resources to update same-season-relief well practices or equivalency initiatives that may support oil and gas exploration in Canada's Arctic waters. A similar situation was experienced with drilling contractors, with the notable exceptions of Stena Drilling (floating rigs) and Nordic Callista (land-base rigs). The data gaps had a negative impact on the analysis, and consequently on the project baselines. Nevertheless, there were several service companies and subject matter experts that assisted and advised the project team throughout the development of the scope of work.

Closing remarks

The project team involved in this survey worked under the fundamental principles of impartiality and independence. "Independent" in that there was no financial interest in the outcome or from featuring the various equipment, technologies, and practices. "Impartial" in the sense of having an unbiased approach based on sound engineering judgement, particularly to the same-season-relief well policy and equivalency, as well as the actual techniques that needed to be featured in this report. The authors believe that this is a key aspect of due process to support the science-based approach to manage of oil and gas resources in Canada's Arctic offshore. The project team appreciates the detailed and candid input provided by the extremely knowledgeable and helpful small and medium-sized enterprises (SMEs) and staff from all the companies that supported this survey. Most importantly, this work could not have been completed without the Committees' commitment to fulfilling its mandate to conduct a science-based review of oil and gas activities in Canada's Arctic offshore.