The Offshore Well Integrity (Operate Phase) Inspection Guide Open Government Status Fully Open Publication Date 19/09/2018 Review Date 23/04/2029

Review History Date Changes

16/05/2022 Issue 3 - Minor changes – transition to new IG format. 23/04/2026 Issue 4 – Minor changes.

Target Audience ED Offshore Inspectors / ED Specialist Inspectors

Contents • Summary (p.2) • Introduction (p.3) • Relevant Legislation (p.3) • Action (p.4) • Background (p.4) • Other relevant Inspection Guides (p.7) • Specialist Advice (p.7) • Organisation (p.7) Targeting Timing Resources

Recording & Reporting Health and Safety • Appendices (p.8) Appendix 1 - Pre-visit information Request Documentation review Appendix 2 - Well Operator Self-Assessment – System Review Appendix 3 – Role Specific Interview Outline Including Sample Agenda Appendix 4 – Role Specific Questionnaires Appendix 5 – Risk Assessment Review Appendix 6 - Application of EMM and Dutyholder Performance assessment Appendix 7 - References

Summary This IG outlines an approach to the inspection of dutyholder’s arrangements with respect to the inspection of well operators’ well integrity arrangements for the operate phase of a well lifecycle for wells onshore in Great Britain and offshore in the UKCS, and the key areas that inspectors should consider when inspecting this topic. It also sets out the criteria for satisfactory and unsatisfactory performance factors against which dutyholder performance will be rated. References are made to technical standards and guidance that inspectors will use to form and opinion of legal compliance.

Well Integrity requires dutyholders to ensure the integrity of its wells, barriers and the pressure containment boundary throughout the well life cycle from design to final abandonment.

The well-operator should consider the benefits of having a policy defining its commitments and obligations to safeguard health, environment, assets and reputation by establishing and preserving well integrity. This well integrity policy should be endorsed at a senior level within the well-operator’s organisation but may sit within a wider policy framework rather than a stand-alone document.

The well-operator is responsible for assessing the well risks and reducing them to ALARP. This should be demonstrated to the offshore installation duty holder who has primary responsibility for the safety of the installation and the personnel on board.

Well-operators should have a system for ensuring well integrity throughout the life cycle. Management of operations may be devolved but the responsibility for the integrity of the well remains with the well-operator.

Introduction The purpose of this Inspection Guide is to provide information and guidance to OMAR Inspectors to support the delivery of consistent and effective inspection of dutyholder arrangements to support the safe operation of hydrocarbon wells.

The inspection requires well operators to perform a self-assessment of their Well Integrity Management System (WIMS) to ascertain compliance with relevant standards and guidance [Appendix 2] and provide the associated documentary evidence for further review by the inspector. This review will subsequently be followed by a set of role-specific questionnaires [Appendices 3&4]. The effective management of risk is also critical to impaired wells as they age throughout their life cycle. Wells Risk Management is treated as a separate but complimentary assessment [Appendix 5].

The questions were developed from international standards and guidance and examples of good industry practice; specifically: ISO 16530-1:2017 Well Integrity Part 1: Life Cycle Governance and Offshore Energies UK (PNA O&G UK) Well Life Cycle Integrity Guidelines.

Success criteria (fundamental requirements) are listed under the inspection topics [Appendix 6]; these cover the key issues that inspectors should consider when carrying-out inspections against each core intervention issue. In some instances, not all the success criteria will apply so inspectors should make a judgement regarding which of these are relevant in each case.

This Inspection Guide highlights key areas for inspection and provides a framework against which inspectors can judge compliance, assign performance ratings and determine what enforcement action should be taken with respect to legislative breaches that may be found.

Relevant Legislation Well-operators should satisfy themselves that their procedures and processes for complying with all relevant legislation are effective. Those key statutory requirements are:

The Offshore Installations and Wells (Design and Construction, etc) Regulations 1996, as amended, hereafter referred to as DCR [Ref 11] which apply to all oil and gas related wells both onshore and offshore;

The Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015 hereafter referred to as SCR 2015 [Ref 12] which apply offshore in external waters of the UK Continental Shelf;

The Offshore Installations (Safety Case) Regulations 2005 hereafter referred to as SCR 05 [Ref 13] which apply offshore in Great Britain internal waters; and,

The Borehole Sites and Operations Regulations 1995 hereafter referred to as BSOR [Ref 14] which only apply onshore Great Britain.

Action Inspectors should review relevant documentation (see Annex 1 Pre-visit Information Request) prior to the installation or HQ visit and test compliance during the installation / HQ visit against the “Success Criteria“ given in Appendix 6.

By the conclusion of the inspection, it should be possible to:

• Determine if the Well Operator’s well integrity management system for wells in the operate phase of their lifecycle is suitable and sufficient.

When carrying out inspections covered by this IG inspectors should:

• Assess dutyholder responses against the success criteria in Appendix 6 • Use the performance descriptors in Appendix 6 to: o Determine the appropriate performance rating o The initial enforcement expectation o Consider how and when the issues raised during an inspection are to be closed out

Background The loss of well integrity can result in major accidents and presents a severe risk to the personnel, asset and environment. In the UK, all onshore and offshore well operators must comply with the Offshore Installations and Wells (Design and Construction, etc.) Regulations 1996 (DCR). The DCR place goal-setting duties on well operators, to ensure that there is no unplanned escape of fluids from the well and risks to the health and safety of persons are as low as is reasonably practicable (ALARP) throughout the well lifecycle.

The accepted good practice philosophy is that all wells are to be equipped with two well barriers against the reservoir, and that the well barriers are to be as independent of each other as possible. This ensures no single failure of a component can lead to unacceptable consequences. If one of the barriers fails, the well has reduced integrity and operations have to take place to replace or restore the failed barrier element. These barriers can deteriorate, or its functional efficiency reduced during the well lifecycle resulting in the leakage of hydrocarbons.

The referenced ISO 16530-1-2017 document was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 4, Drilling and production equipment.

A well lifecycle is detailed below:

This inspection guide is concerned with the operational phase. Wells will spend the vast majority of its life in the operate phase therefore this guide targets the greatest cumulative risk. The design phase, construction, intervention and abandonment phases are inspected through the Well Notification process.

ISO Standards

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

Offshore Energies UK (PNA Oil and Gas UK) Guidance The Wells Forum produced guidance on well integrity for Offshore Energies UK (OEUK). They were written by the Well Integrity Workgroup which included experts from several operators and were reviewed by external stakeholders that included other Wells Forum members and the HSE and OPRED.

The ISO Standard and OEUK guidance are relevant to;

• all well-operators of GB & UKCS wells • well integrity during the full lifecycle of the well

The guidelines address arrangements for well integrity, contents of a well integrity management scheme, administration of a well integrity management scheme, effective implementation of the well integrity management scheme, wells risk assessments, barriers, component performance standards, operating limits, monitoring and surveillance requirements, wells maintenance, integrity failures, management of change, records, effective audit and review during the relevant phase of the well life cycle.

LEGAL REQUIREMENTS There is a general duty under Regulation 13 of the Offshore Installations and Wells (Design and construction, etc) Regulations 1996 for the well operator to:

Ensure that a well is so designed, modified, commissioned, constructed, equipped, operated, maintained, suspended and abandoned that:

a) so far as is reasonably practicable, there can be no unplanned escape of fluids from the well; and b) risks to the health and safety of persons from it or anything in it, or in strata, to which it is connected, are as low as reasonably practicable.

Regulation 16 requires:

The well operator shall ensure that every part of a well is composed of material which is suitable for achieving the purposes described in regulation 13(1).

The Offshore Installations (Offshore Safety Directive) (Safety Case etc) Regulations 2015 requires (at Schedule 6) duty holders of production installations to describe in the safety case how they will comply with the above regulations and a description of how duty holders ensure the suitability of the safety and environmentally critical elements.

Other relevant Inspection Guides Wells Competence, as there requires to be competent personnel involved in well integrity activities.

Specialist Advice Specialist advice should be sought from ED2 Well Eng & Ops in the following circumstances: the inspection guide should only be used in conjunction with a member of the ED2 Well Eng & Ops team.

Organisation

Targeting

Inspections should be planned in accordance with OMAR duty holder intervention plans.

Timing

Inspectors should undertake well integrity inspections as part of the agreed OMAR Intervention Plan; when intelligence indicates intervention is necessary, or as part of an investigation following an incident.

Resources

Resource for the undertaking of well integrity management interventions will be agreed as part of the OMAR Work Plan or by agreement between discipline specialist team-leaders and inspection management team-leaders, as appropriate.

Recording & Reporting

The dutyholder performance ratings should be entered on the Inspection Rating (IRF) Tab of the relevant installation Intervention Plan Service Order. Findings should be recorded in the post inspection report and letter.

Health and Safety There are no specific health and safety issues relevant to this topic that needs to be considered when conducting the inspection.

Appendix 1 Pre-visit information Request Documentation review The need for a Well Integrity Management System inspection using this guide is likely to be defined by the OMAR intervention planning process but may be implemented separately by HSE wells specialists to respond to: complaints, investigations, newly appointed well operators, changes in well operator’s well stock etc.

This appendix details the typical information that should be requested prior to a Well Integrity Management System inspection. The intention is to gauge the robustness of the system, and provide inspectors with information which can inform their questionnaires:

• The well operator should complete the self-assessment questionnaire contained in appendix 2 detailing the documentary evidence for their response. These documents should be sent through for inspection prior to the interviews. These documents are likely to include:

o A current copy the documents which contain; the Well Integrity Policy, The Well Integrity Strategy and Barrier Management Policy. o A current and complete copy of the arrangements for: Well Integrity, Deviations and Dispensations, and associated Risk Assessment. o Details of the individual position responsible for the management of well integrity during the operate phase of the well lifecycle. o A definitive list of wells covered by the arrangements. [Using NSTA & company nomenclature] o Details of the management of well integrity KPIs including a current well integrity status of the well operator’s wells. o Two examples of current or recently approved well deviation/dispensation documentation including any relevant supporting documentation and risk assessments. o Performance Standards for the wells SECEs during the operate phase. o Details of any Remedial Action Requests (RAR) or comments from the Independent Competent Person (ICP) related to the wells from the latest well verification activities.

It is anticipated that this documentation may take some time to collate and therefore notification of an inspection and requests for information should be made, wherever possible, in a timely manner when part of the planned intervention strategy.

Inspectors shall review the self-assessment against the provided documentation in advance of the interviews to ensure that clarification questions are raised during those interviews.

Appendix 2

Well Operator Self-Assessment – System Review

Well Integrity Policy and Strategy; 1. Is the Well Integrity Policy clear? The Well Operator should have a policy (or other Evidence should include the document reference to Does it safeguard HS&E? Is it documents that clearly achieve the same aim as a which the information is contained along with the endorsed at a senior level? policy) defining its commitments and obligations to chapter, page and paragraph such that it is easy to safeguard health, environment, assets and reputation trace by establishing and preserving well integrity. This well integrity policy shall be endorsed at a senior level within the Well Operator organisation.

2. Does the WIMS explain how the The Well Operator well integrity management system Well Integrity Policy will be (WIMS) should clearly indicate how the policy is achieved? interpreted and applied to well integrity.

Resources, Roles, Responsibilities and Authority Levels; 3. Are roles and responsibilities Each Well Operator should define the roles and clearly defined? responsibilities for all professional, supervisory, operational and maintenance personnel required to manage the well integrity system. Roles and responsibilities should be documented.

4. Does the WIMS reference an Each Well Operator should ensure that their personnel appropriate wells personnel (employees and contractors) who participate in well competency system? integrity activities are competent to perform the tasks assigned to them. Each Well Operator should define well integrity personnel competency requirements to ensure that well integrity activities are carried out in a manner which is both safe and efficient as regards protection of health, the environment and assets. A competence performance record should be maintained that demonstrates compliance.

Risk Assessment Aspects of Well Integrity Management; 5. Is there an established procedure The risk assessment procedure chosen should be for wells risk assessments or is a suitable and sufficient for wells matters. Where a corporate risk assessment used? separate wells specific procedure is used it should be aligned to and reference the corporate risk assessment procedures.

6. Is the risk assessment matrix The Well Operator should determine appropriate suitable for MAH wells risks? levels/definitions for consequence (severity) and likelihood of occurrence (probability) categories on the risk assessment matrix axes.

Well Barriers; 7. Have the barriers for each well The Well Operator should define a barrier philosophy type been documented? Are for each of the well types within the WIMS. Typically these sufficiently detailed and this will require two barriers in the direction of flow. suitable for downhole conditions? Where two barriers are not achieved an ALARP demonstration may be required.

8. Does the WIMS mandate a risk In cases where a barrier envelope cannot be assessment where a well is maintained according to the original design outside original design specification, the Well Operator should perform a risk specification? How should this be assessment to establish the required controls to documented? mitigate the risk. This risk assessment is likely to be included in a formal Management of Change process.

9. Does the well operator use well Well barrier schematics as mandated by NORSOK barrier schematics to demonstrate D10 are effective. ISO 16530-1 also states that well the design barriers or capture barrier schematic should be used. In some cases, current well barrier status? If not other methods such as spreadsheets tables may be is the solution they employ used where they are equally effective. equally effective?

Well Component Performance Standards; 10. Are performance standards in The Well Operator should define performance place for each type of well? Do standards for each well type. Performance standards, they detail the requirements for supported by the risk assessment, are the basis for the maintenance, assurance and development of maintenance and monitoring verification activities? Are the requirements company standards sufficiently detailed and refer to appropriate industry standards?

11. Have acceptable leak rates been Using a risk-based approach, the Well Operator should determined and documented for define their acceptable leak rates and testing each well component? frequency for individual barrier elements for all well types within the acceptance criteria described below.

12. Are these contained within a Has the well operator defined leak rates for individual matrix? well components in a leak rate matrix? If not have equally effective measures been identified?

13. How do leak rates compare with ISO Acceptable leak rates shall satisfy at least all the ISO minimums and other industry following acceptance criteria: norms?  leak across a valve, leak contained within the envelope or flow path: ISO 10417:2004 & API 6AV2.  leak across a barrier envelope, conduit to conduit: not permitted unless the receiving conduit is able to withstand the potential newly imposed load and fluid composition.  no leak rate from conduit to conduit exceeding the leak rate specified in ISO 10417:2004, which defines an acceptable leak rate as 24 l/h of liquid or 25.4 m³/h (900 scf/h) of gas.  no unplanned or uncontrolled leak of wellbore effluents to the surface or subsurface environment.

ISO goes on to recommend a maximum leak rate for tree valves at 3cc/min/inch. This is consistent with other international standards.

Within the UKCS a number of operators apply a liquid leak rate of 2cc/min/inch as their leak rate acceptance criteria, with any leakage above 50cc/min indicating washout. This is significantly below API 14B of 400cc/ minute. Where an operator has determined an acceptable leak rate for valves above the 2cc/min/inch value they may be asked to demonstrate why that approach has been deemed ALARP.

Well Operating Limits 14. How are operating limits identified The Well Operator should identify the operating