The SPE Forum, “Shaping the Next Wave in Well Plugging and Abandonment” was held 18–22 March in The Hague, The Netherlands. It brought together leaders from production and service sector companies, regulators, and stakeholders to discuss issues that are shaping the well plugging and abandonment sector. The event attracted 77 specialists from around the world.
Below are highlights and key points from each of the various sessions.
Session 1 identified stakeholders, their hopes and concerns, risks and opportunities.
- There are large opportunities from agreed risk assessment methodology, tailored for the well.
- Operators and governments align fairly well in objectives, hopes, and fears.
- Authorities have very diverse interests, are concerned about leaks, technical standards, failure mode assessments, gold plating, lines of credit, maximized recovery, orphan wells, lack of transparency, accidents, emissions. Operators’ concerns are primarily around reputation and long-term integrity, liabilities, budget, regulatory clarity. Opportunities lie in collaboration, standards, and continuity.
- Multiple service providers see market share and differentiation as opportunities. They are concerned with penalties, scope overestimates, and project deferment.
- Single service providers struggle with long-term support from operators and regulators, lack of risk sharing, and early cutting of funding. Intellectual property is an opportunity.
- Academia and technology developers have concerns about R&D funding, access to field practice, exclusivity requests, and regulations that stifle progress. Opportunities relate to incubator (seed) funding and accelerating standards/regulations.
- The public is often concerned about environmental harm and loss of value. Extra compensation or community funding may be welcomed as an opportunity.
Session 2 discussed uncertainties that surround the well and subsurface conditions.
- There is no shortage of methods of integrity recovery that have been tried.
- The industry needs to look further than the mean in its data and models. The implications of outliers can be undesirable.
- The industry often looks at the primary elements of the abandonment operation but needs to also look at the system and the system objectives.
- Companies need to understand the subsurface and have access to data, which requires greater interaction from subsurface disciplines early in the process.
- The industry is late in the lifecycle of our wells and the uncertainty in the condition and state of wells is inherent in everything that we do.
- There is no shortage in creativity, initiative, and opportunity in and outside of our industry—we should use it.
Session 3 showed three applications of a technical limit approach for the planning and execution of plugging and abandonment campaigns. The following key value drivers for a technical limit approach were highlighted.
- Clear scope definition (including any non-well work). Pre-diagnostics work is key to avoid surprises and unplanned scope change.
- Plan for flexibility in a campaign in case of trouble wells.
- Plan for large campaigns to leverage learning curve effects.
- Continuity of staff who specialize in plugging and abandonment.
- For platform wells, integration with platform/production teams is key. Platform status is also key (cranes, safety systems, gratings, etc.).
- Rigless can be an appropriate intervention platform, which leverages through tubing opportunities.
- For subsea, integration is key to reduce both wells/surface cost (e.g., flushing).
- Leverage technology to the fullest (e.g., single-trip systems, perf and wash).
Session 4 discussed the regulator’s perspective.
- There is consensus that residual risk may remain after well plugging and abandonment. A framework needs to be agreed to ensure these cases are tolerable.
- Most see a benefit from harmonization of regional common practices/guidelines across borders. Concerns were raised about regional differences, compromises, time to agree, and cost differences. Regional standards (e.g., across the North Sea) could be feasible.
- There is increased focus in society on the environment and there are high expectations for prudent plug and abandonment operations among regulators and the public at large.
- Balance between cost and quality of plugging and abandonment needs to be maintained. Trend is toward risk assessments, shorter plugs, new materials/methods, and efficient verification.
- In risk-assessed approaches, it is critical to use correct input and method, competency, and documentation. Assessments of uncertainty are not always performed according to the same format/quality.
- Plug and abandonment design and verification should start when designing and drilling the well. An early and systematic approach and good well life-cycle documentation will improve the acceptability process and verification.
Session 5 discussed materials.
- Ordinary Portland Cement (OPC) has served and continues to serve the industry well with many successful permanent abandonments to date.
- A range of materials was discussed, including bentonite, geopolymers, (epoxy) resins, silicates, thermite, magnetorheological cement, thermally activated bismuth, shale/salt as a barrier, and sized sand slurries. Some of these materials may be used either as remedial materials, as augmenting OPC applications, or as potential OPC replacements. The potential for composite applications also exists.
- All new and alternative materials have pros and cons. Long-term durability and reliability is being assessed. Materials are in different stages of development.
- Field-proven shale/salt as an annular barrier can simplify, and reduce the costs of, abandonments by avoiding casing milling and pulling, allowing rigless plug and abandonment.
- The industry needs to improve incubator support for technology providers/startups and facilitate faster technology transfer and commercial application of new materials and methods.
Session 6 covered well access issues and novel techniques.
- Wide variations in well challenges in the North Sea alone make it hard to standardize practices.
- Overburden deformation can cause obstacles, and operators are pushing development of multiple technologies to create access in order to set permanent barriers
- Extensive investment from both operators and developers is taking place without guaranteed commercial success. There is a “traffic jam” of advanced technology at the commercial stage, requiring field trials.
- New efforts to repair wells are elaborate and expensive, but can save substantial sums
- Experience from nuclear decommissioning and other sectors such as automotive, manufacturing, and the military has enabled oilfield applications to become viable.
Session 7 discussed the merits of different verification methods and how to facilitate remediation.
- A weight/load test is relevant when there is uncertainty but is of limited value for repeats in casing with a base.
- A pressure test can identify a gross defect but is less suitable for determining seepage.
- An inflow test should be considered for critical wells with extended duration if uncertain. The method is less meaningful for depleted plugged and abandoned wells.
- Logging tools are advancing, but further understanding is needed.
- Micro-volume techniques with enhanced instrumentation could facilitate proof of new materials/placement and help critical applications. Inflow test principles are preferred.
- Any remediation could be facilitated by ease of surface access, documentation, tubular continuity, entry plan, or magnetic tags.
A number of priority areas were identified by participants to progress plugging and abandonment challenges and opportunities.
- The need for an international standard for qualification testing of plugging material, both hydraulic sealing and durability.
- Steps to develop an agreed quality assurance process for verification of cement plugs.
- Better data for better risk assessments. Identify relevant input data for risk assessments. Enhance examination and interpretation of available data. Consider computer analysis techniques and interpretation algorithms. For new wells, enhanced capturing during construction and production life with final plugging and abandonment in mind.
- Take steps toward skill development for professionals and attractiveness of growth business. Strengthen profile of P&A and its value in energy transition and environmental prudence.
- Incubator mindset: Steps to develop support structures for start-ups and technology initiatives.