Environment inspections focus on source control

Article published in the Regulator | Issue 2: 2019 

NOPSEMA’s regulatory focus on the prevention of major accidents to protect the health and safety of people at or near facilities and the environment is something that is well documented and understood across industry and the public alike. Another core focus area which is perhaps a little less public is the work that we do to ensure offshore petroleum titleholders are best prepared to launch all appropriate mitigating response actions in the unfortunate case that a major accident does occur.

One set of response actions is described in technical circles as ‘source control.’ If the accident is an offshore ‘blowout’ or ‘loss of well control’ after a failure of a blowout preventer then the source control options available are often limited to various dynamic/static/top kill approaches including the possible installation of a capping stack or drilling of a relief well.

Real world experience has been that titleholders work towards simultaneously implementing as many of these source control options as makes feasible sense. Where access and safety allows, top kill efforts are undertaken from the original rig or another rig brought to the site. Where the original rig is disabled, has been lost or is simply not safe to use, a capping stack may be brought into play by one or more specialist offshore installation vessels. Other teams will be surveying the site, removing debris with remote operated vehicles (ROVs), fighting fires, or undertaking other actions to enable a safe response. This may include, for example, injecting subsea dispersants at the wellhead or spraying surface dispersants on the water where oil surfaces to minimise explosive vapours. Meanwhile, at a safe distance upwind/current, a rig sourced in the region on an emergency basis will begin drilling a relief well to intercept the blowout well thus eventually allowing a more permanent ‘bottom kill’.

The complexity of these response actions makes it clear that advance planning is key to ensuring their success; it is simply not good enough to wait until a major accident occurs before response plans are made. The good news is NOPSEMA, as the national regulator, and the offshore petroleum industry agree on this point. The challenge is ensuring the latest technological developments and best practices, world-wide, are recognised, translated into the Australian context, are consistently implemented, and fit for the circumstances that may unfold.

It is with this in mind that inspectors in NOPSEMA’s Spill Risk and Well Integrity teams have been undertaking targeted inspections on source control. In the year Q1-2017 to Q1-2018 seven inspections were carried out with a source control focus. Six titleholders, large and small, were inspected in connection with drilling (5 inspections), production (1 inspection), and well intervention activities (1 inspection). Following a standard format that allowed for variation to meet the diverse characteristics of the different activities, NOPSEMA’s inspectors looked at planning to ensure that the level of detail was commensurate to the risk, service arrangements with specialist third party providers (e.g. well intervention specialists, transport firms, ROV operators), availability of source control expertise and management, and equipment arrangements (e.g. capping stack providers, availability of relief well rigs and long-lead time materials).

During these inspections, NOPSEMA found a significant amount of good practice. For example, ongoing maintenance of tracking systems for suitable relief well rigs and capping stack deployment vessels, the rigorous study of activity and location-specific capping stack feasibility, and detailed well-specific logistics studies for mobilising equipment such as capping stacks to site. Similarly, a range of areas were identified for improvement and NOPSEMA issued recommendations to address these aspects. These findings can be summarised in four categories, including: ensuring availability, preparing to meet environment plan timeframes, preparedness documentation, and preparedness planning.

Looking to the future, NOPSEMA’s focus on source control preparedness in environment inspections will continue. NOPSEMA’s current inspection planning foresees targeting all titleholders and high risk activities as dictated by inspection policy targets as well as when opportunities for ad-hoc inspections arise.