Guidelines For Well Operators On Well Examination: August 2017 [PDF]

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Guidelines for Well Operators on Well Examination Issue 2

August 2017

Acknowledgments In preparing and publishing this document, Oil & Gas UK gratefully acknowledges the contribution of members of the Wells Forum Well Examination work group, namely: •

David Brink (co-lead) – Well Engineering Manager, Maersk Oil North Sea UK Ltd

•

Les Browne (co-lead) – Managing Director, Chris Dykes International Ltd

•

Peter Sproul – Drilling Superintendent, Dana Petroleum

•

Carl Hills – Well Examiner, Total E&P UK Ltd

•

Zoe Fuller – Well Examination Manager, NRG Well Examination Ltd

•

Keith Stewart – Well Engineering Manager, Repsol Sinopec Resources UK Ltd

•

Grant Moody – HM Principal Inspector of Health and Safety, HSE

•

Stacey Murphy – HSE Manager Wells, Shell UK Ltd

•

Nick Low – Senior Drilling Engineer, LR Wells

While every effort has been made to ensure the accuracy of the information contained in this publication, neither Oil & Gas UK, nor any of its members will assume liability for any use made of this publication or the model agreement to which it relates. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior written permission of the publishers. Crown copyright material is reproduced with the permission of the Controller of Her Majesty’s Stationery Office. Copyright © 2017 The UK Oil and Gas Industry Association Limited trading as Oil & Gas UK ISBN: 1 903 004 88 8 PUBLISHED BY OIL & GAS UK London Office: 6th Floor East, Portland House, Bressenden Place, London, SW1E 5BH Tel: 020 7802 2400 Fax: 020 7802 2401 Aberdeen Office: Exchange 2, 3rd Floor, 62 Market Street, Aberdeen, AB11 5PJ Tel: 01224 577250 Fax: 01224 577251 [email protected] www.oilandgasuk.co.uk

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Guidelines for Well Operators on Well Examination August 2017 Contents 1

Summary

2

Arrangements for Well Examination 2.1 Responsibility for the well examination scheme 2.2 Scope of the Safety Case Regulations 2015 and the Design and Construction Regulations 1996 in regard to well examination 2.3 Guidance on ALARP 2.4 Responsibility for wells within a well examination scheme 2.5 Wells covered by the well examination scheme 2.5.1 New wells 2.5.2 Operation and maintenance of existing wells 2.5.3 Intervention and workover of existing wells 2.5.4 Wells where activities or operations have been suspended before full construction 2.5.5 Wells where activities or operations have been suspended after full construction 2.5.6 Abandoned wells 2.6 Implementation of the well examination scheme 2.6.1 Review and revision of well examination scheme 2.7 Independence of the well examiner 2.7.1 Types of well examiners 2.8 Competence of well examiners 2.9 Well control equipment

10 10

Contents of a Well Examination Scheme 3.1 General requirements 3.2 Depth and extent of well examination 3.3 Examination through the well life cycle 3.3.1 Design 3.3.2 Well construction (drill, test and complete) 3.3.3 Commission 3.3.4 Operate and maintain 3.3.5 Intervention and workover 3.3.6 Suspend 3.3.7 Abandon 3.4 Reports from the well examination scheme

16 16 16 18 18 19 19 19 20 21 21 21

3

8

Page 3

10 10 11 11 12 12 12 12 13 13 13 13 14 14 15 15

3.5

3.4.1 Resolving disputes Standards used in well examination 3.5.1 Well operator’s internal standards 3.5.2 Industry standards

22 22 22 23

4

Limits of the Well Examination Scheme 24 4.1 General duty of the well operator 24 4.1.1 What is excluded from a well examination scheme 24

5

Administration of a Well Examination Scheme 5.1 Information, instruction, training, and supervision 5.2 Keeping records

25 25 25

6

Interface with Installation Verification 6.1 Boundary of well examination scheme 6.2 Interface with verification over the well life cycle 6.2.1 Well design 6.2.2 Well construction 6.2.3 Commission 6.2.4 Operate and maintain 6.2.5 Intervene and workover 6.2.6 Well abandonment

26 26 26 26 27 27 27 27 27

7

Additional Well Examination Requirements of SCR 2015 for Wells in External Waters Appendices A References B SCR 2015 Parts Relevant to Well Examination C Background to these Guidelines

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28 29 29 31 33

List of Abbreviations Abbreviations

Definitions

ALARP

As low as reasonably practicable

API

American Petroleum Institute

BEIS

Department of Business, Energy and Industrial Strategy

BOP

Blow Out Preventer

BSOR

Borehole Sites and Operations Regulations 1995

CA

Competent Authority (SCR 2015 only. Note that the OSDR acts as the Competent Authority)

DCR

The Offshore Installations (Design and Construction, etc) Regulations 1996

HSE

Health and Safety Executive

ISO

International Organization for Standardization

OGA

Oil & Gas Authority

OSDR

Offshore Safety Directive Regulator (SCR 2015 only. Note the HSE and BEIS, work in partnership as the OSDR)

SCR 2015

The Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015

UKCS

United Kingdom Continental Shelf

WLCPF

Well Life Cycle Practices Forum (Renamed the Wells Forum in 2016)

Well

a. b.

Well Examiner

An independent and competent person who performs functions in relation to a well examination scheme.

Well Operation

a.

b.

Well Operator

A well made by drilling; and A borehole drilled with a view to the extraction of petroleum through it or another well, and includes any device on it for containing the pressure in it.

The drilling of a well including the recommencement of drilling after a well has been completed, suspended or abandoned by plugging at the seabed and Any operation in relation to a well which may result in an accidental release of fluids from that well which could give rise to the risk of a major accident

SCR 2015 Guidance [Ref 7] states: in relation to a well in Great Britain, means the person appointed by the licensee for the well to execute the function of organising and supervising all operations to be carried out by means of such well or, where no such person has been appointed, the licensee; and in relation to a well in external waters, has the meaning given in regulation 2 of the Offshore Petroleum Licensing (Offshore Safety Directive) Regulations 2015…

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Abbreviations

Definitions which states: “well operator” in relation to a well or proposed well means a person appointed in accordance with regulation 5 or 6 to conduct the planning or execution of well operations [Ref 6].

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Foreword Issue 2 of these guidelines has been produced for Oil & Gas UK by the Wells Forum Well Examination work group. The guidelines have been updated following the introduction of the Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015. These regulations were introduced in order to comply with the EU Directive 2013/30/EU on safety of offshore oil and gas operations. These new regulations, which include some additional well examination requirements, are applicable only to wells in external waters. For wells in internal waters, such as estuaries and for wells onshore, the arrangements for well examination are still covered by Regulation 18 of the Offshore Installations and Wells (Design and Construction, etc.) Regulations 1996. The purpose of this document is to help well operators comply with the applicable regulations on well examination. These guidelines are relevant to all oil and gas well operators working in the following areas: •

External waters, that is, the territorial sea adjacent to Great Britain (GB) and any designated area within the United Kingdom continental shelf (UKCS);

•

Internal waters of Great Britain, such as estuaries; and

•

Onshore Great Britain, where appropriate.

They are relevant to all aspects of wells and well operations throughout the well life cycle from initial design to abandonment including production / injection stages and all suspended wells. These guidelines also cover well operations from all types of offshore installations including production and non-production installations and vessels. Interpretation In these guidelines: •

the word “shall” is only used when the instruction is explicit in legislation or physical laws. Otherwise the word “should” indicates the workgroups understanding of current good practice. “May” is used where there are alternatives available to the well-operator and either, or any one, of those is acceptable. In these instances the well operator will have to use its best technical judgement to decide which is preferable in the particular situation.

•

reference to any legislation or publications includes a reference to that legislation, publications may be amended, extended or re-enacted from time to time;

•

reference to the singular includes the plural and vice versa;

•

reference to “include” means “including but not limited to”;

•

the headings are used for convenience only; and

•

regard has only been made to the jurisdictions within Great Britain, the internal waters of Great Britain, and the external waters that surround Great Britain (that is the territorial sea adjacent to Great Britain and any designated area within the UKCS).

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1 Summary For well examination, wells personnel should read and apply The Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015 and The Offshore Installations and Wells (Design and Construction, etc.) Regulations 1996 (hereafter referred to as SCR 2015 and DCR respectively) and their related guidance plus all other legislation relevant to wells and well operations. These Oil & Gas UK guidelines on well examination support the regulations and associated guidance issued by the regulator but they do not replace an understanding of the regulations. Well examination requirements for wells in external waters have been revoked from DCR (Regulation 18), updated to accommodate new principles and duties, and placed in SCR 2015. For wells in internal waters, the well examination requirements of DCR (Regulation 18) still apply. These should be read in conjunction with the Offshore Installations (Safety Case) Regulations 2005 (SCR 2005) and related guidance. For onshore wells, the well examination requirements of DCR (Regulation 18) still apply. These should be read in conjunction with The Borehole Sites and Operations Regulations 1995 (BSOR) and related guidance. For all wells the DCR regulations, excluding Regulation 18, still apply. This is summarised in the table below: Well Location

Well Examination Regulations

Well Regulations in addition to Well Examination Regulations

External Waters

SCR 2015 Regulations 2, 8, 9, SCR 2015 + DCR 1996 11, 12, 13, 21 and 27

Internal Waters

DCR 1996 Regulation 18

SCR 2005 + DCR 1996

Onshore

DCR 1996 Regulation 18

BSOR 1995 + DCR 1996

Well operators shall list all the wells for which they are responsible, including suspended wells and wells that have been inherited from other well operators. Well operators shall have a well examination scheme to describe arrangements for “independent and competent persons” to examine all these wells and any well operations. The well examination scheme provides an independent check that the well is so designed, constructed and is maintained in such repair and condition 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 is reasonably practicable.

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Well examination should assure the well operator that the well is designed and constructed properly and is maintained adequately. It helps to demonstrate that the pressure boundary of the well is controlled throughout the well life cycle from design to abandonment. The well examination scheme should check that the well operator has processes (for example a well delivery process) in place to cover well operations throughout the well life cycle. The well examiner should check that the well operator complies with its own internal processes. The depth of well examination will depend on the criticality of the operations and the hazards, as assessed by the well examiner. The well operator should appoint an independent and competent person to carry out the well examination as described in the scheme. There should be a mechanism for resolving any disputes between the well examiner and well operator. The ultimate decision is the responsibility of the well operator. The well examination scheme should cover the full life cycle of the well from design to abandonment, although operational responsibility for the well may change during the life cycle. The well examination scheme should cover everything within the well pressure containment boundary. Well examination should compare the designs and operations against both the well operator’s internal standards and good industry practice, notably, that described in Oil & Gas UK Well Integrity Guidelines. The well operator should review and revise the well examination scheme as often as may be appropriate. Any changes to the well examination scheme or the well operator’s internal standards must be communicated to the well examiner. All well operator staff involved in the design, construction and the continuing integrity of a well should have a good understanding of the relevant regulations and the well examination scheme and be aware of the information that must be communicated to the well examiner.

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2 Arrangements for Well Examination 2.1

Responsibility for the well examination scheme SCR 2015 and DCR are clear that it is the responsibility of the well operator to: •

make and put into effect well examination arrangements (scheme);

•

ensure the well examination scheme is followed;

•

appoint a well examiner;

•

ensure the well examiner is independent of the well operations line management;

•

ensure the well examiner is competent for the well operations being examined;

•

take suitable action on any reports made by the well examiner; and

•

review and revise the arrangements as often as may be appropriate.

The well examiner should not manage the well examination scheme. This is the responsibility of the well operator. A position in the well operator’s organisation should be identified as responsible for the well examination scheme. This should rest with the job position, not an individual.

2.2

Scope of the Safety Case Regulations 2015 and the Design and Construction Regulations 1996 in regard to well examination These regulations cover the well examination of oil and gas wells. They are relevant to all aspects of wells and well operations throughout the well life cycle from initial design to abandonment including production / injection stages and all suspended wells. Where operating licences are sold or transferred between companies, it is the responsibility of the new licensee to determine “well operator” status, the well stock portfolio, and to ensure that well examination arrangements are in place. All suspended wells are included in the regulations and should be included in the well operator’s well examination scheme.

2.3

Guidance on ALARP The well aspects of DCR and SCR 2015 are based on the ALARP principle (as low as reasonably practicable). This principle is a cornerstone of UK health and safety legislation. Training for well engineers should include guidance on the ALARP principle. Information on this is found on the HSE website ALARP “at a glance”. An element of well examiners’ competency should be an understanding of the ALARP principle. See Oil & Gas UK publication Guidelines for well operators on competency of well examiners.

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2.4

Responsibility for wells within a well examination scheme The definition of well operator varies slightly between the applicable regulations but it is generally understood to be the organisation appointed to be responsible for organising and supervising the planning and execution of well operations. The well operator is responsible for the integrity of their wells and their well examination scheme. DCR and SCR 2015 requires that the well examination scheme covers wells from design to abandonment. The well operator should ensure there is continuity in the well examination scheme when operational responsibility for a well is transferred. For example: •

between departments (e.g. from drilling to production) in the same company;

•

between organisations (e.g. from well management company to well operator).

As part of any handover of a well, the specific requirements of the well examination scheme should be part of the formal transfer of responsibility. If a subsea well is tied back to an installation operated by another company, the responsibility for that well and its examination remains with the well operator. Wells may be designed, equipped, constructed and commissioned by a well management company. If the legal responsibilities of the well operator are assigned to this contractor, it should be made explicit in a formal agreement between the licensee and the contractor. For wells in external waters, the appointment of a contractor as well operator also requires the approval of the OGA. If not, the licensee remains as the well operator. A production installation duty holder may contract out some or all functions of the installation management. The licensee will remain the well operator unless the legal responsibilities are formally assigned to a contractor and accepted by them.

2.5

Wells covered by the well examination scheme DCR and SCR 2015 state all wells must be included in the arrangements for well examination over their full life cycle. Well operators should ensure that their entire well inventory is covered by their well examination scheme. Well operators should draw up and maintain a comprehensive register of all their wells that are covered by the well examination scheme. This will be useful for their internal management of the well examination scheme and also to demonstrate to the OSDR or HSE, as appropriate, the adequacy of their well examination arrangements. Each well entry should include (if applicable): •

OGA well number;

•

local well number;

•

well name;

•

field;

•

installation to which the well is connected; and

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•

2.5.1

status.

New wells The well examination scheme should cover the complete life cycle of all wells from design until abandonment.

2.5.2

Operation and maintenance of existing wells The well examination scheme should cover all wells during operations, producing or injecting, including routine maintenance. This should include condition monitoring such as annulus pressure monitoring or downhole temperature and pressure monitoring. This phase may also include well entry for information gathering or condition monitoring (for example wireline production logging tool (PLT) logging). An operator who takes over wells from another well operator (for example by purchasing producing assets) should review the well examination and other records for each well. This is part of the process of adding additional wells to the well examination scheme. It is important that the well examination scheme includes any wells, operating or suspended, that have not been re-entered or worked over for some time. It is important that all modifications to wells are recorded by the well operator; minor modifications (for example to wellhead or Christmas tree fittings) can have a significant effect on safety. This type of data may be covered by the well operator’s processes such as management of change or well integrity management. The changes may be collated in an annual well integrity report. The changes should be examined and the process will be defined in the well examination scheme. For offshore production installations, the surface modifications described above may be covered by either the installation verification scheme or the well examination scheme, but should be assessed by an independent and competent person.

2.5.3

Intervention and workover of existing wells The well examination scheme shall cover operations during well interventions and workovers. Such operations may involve a handover of operational responsibility for the well.

2.5.4

Wells where activities or operations have been suspended before full construction The well examination scheme shall cover wells where activities or operations have been suspended before they have been fully constructed (for example after setting the surface casing as part of a batch setting operation).

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2.5.5

Wells where activities or operations have been suspended after full construction The well examination scheme shall cover wells where activities or operations have been suspended after full construction (e.g. successful offshore exploration / appraisal wells that are kept for potential conversion to subsea development wells). Well operators shall include wells where activities or operations have been suspended in their well integrity management system. The well examiner shall check that the wells are monitored as described in the well operator’s management system. Wells inherited from previous well operators must be included in the well operator’s well register and be covered by their well examination scheme.

2.5.6

Abandoned wells Abandonment operations on wells shall be included in the well examination scheme. After abandonment the well is no longer covered by the well examination scheme. Well examination records should be kept for at least six months after a well has been abandoned.

2.6

Implementation of the well examination scheme There shall be arrangements in place before any well design is started; for example, a start-up company should have a well examination scheme before starting the design of its first well. A company purchasing a licence with existing wells shall have a well examination scheme in place before it takes over responsibility for the wells.

2.6.1

Review and revision of well examination scheme SCR 2015 and DCR requires the well operator to review and revise the well examination arrangements as often as may be appropriate, to ensure they are relevant to the wells in the well examination scheme. Reviews may take place: •

when existing wells are brought into a well examination scheme (purchase of field / acreage with wells);

•

when new types of well (e.g. HPHT) are being planned;

•

when there is a change of well examiner;

•

when there are concerns that the well examination scheme is not working well;

•

when changes to the well examination scheme are proposed by the well operator; or

•

when there are changes to legislation which affect well examination.

The details of how, when and by whom these reviews are conducted should be contained in the well examination scheme. The review scope may include: •

compliance with the well examination scheme;

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•

completeness and effectiveness of the well examination scheme;

•

resolving disputes;

•

any changes proposed by the well operator;

•

compliance with new legislation.

All changes to the well examination scheme should be discussed with the well examiner and must be communicated to the well examiner.

2.7

Independence of the well examiner The person or persons carrying out the well examination should be independent of the immediate line management of the well operations involved, and should not have previously borne responsibility for anything that they may examine. It is important that the well examiner is impartial and is independent from pressures, especially of a financial nature. Promotion, pay and reward systems should not compromise the professional judgment of the well examiner. Well examiners should maintain their independence but should be allowed to review whatever information is required to perform their role. They should never be part of the decision making process. They should only assess and comment on work planned or carried out by the well operator.

2.7.1

Types of well examiners Neither SCR 2015 nor DCR specifies how the well examination service should be provided. Currently there are the following types of well examiner (all valid under the regulations). Internal (sometimes referred to as “second party”) well examiners within the same company: •

personnel working for the same parent company based in another country;

•

another business unit in the same country;

•

separate well examination department;

•

individual employed outwith the well operations / drilling department; or

•

licence partner.

External (sometimes referred to as “third party”) well examiners: •

specialist company just providing well examination services;

•

company providing well examination as one of their services; or

•

individuals.

The well operator may use any, or a combination, of these types of service provider. Whichever type(s) is used, the well examination scheme should demonstrate that the well examiner is independent of the immediate line management of the well operations team(s) and should not have previously borne responsibility for anything that they may examine.

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2.8

Competence of well examiners The well examination scheme should address the competence and independence of the well examiner, for both breadth and depth of knowledge. This topic is covered in the Oil & Gas UK document Guidelines for well operators on competency of well examiners. Assessments should be done when the well examiner is first appointed and then as required.

2.9

Well control equipment The well is defined by its “pressure containment boundary” which includes well control equipment. The main well control equipment (drilling BOP and associated equipment) is part of the offshore installation equipment and is managed by the installation duty holder. This equipment should be covered by the installation verification scheme and also reviewed by the well examiner as part of the well pressure envelope. The well examiner’s responsibility is to ensure that the specification of the proposed temporary well control equipment is suitable for the proposed task and that this equipment is covered by a suitable verification scheme. The purpose of the verification scheme is to ensure that the temporary well control equipment is designed and maintained such that it performs to its published specification. At land well sites there is no requirement for an installation verification scheme. Well control equipment is addressed generally in BSOR. Well control equipment forming part of the pressure containment boundary of the well should be covered by a well examination scheme. As for offshore wells and wells in internal waters, the responsibility for well examination resides with the well operator. The following are examples of temporary well control equipment: •

wireline BOP, lubricator, stuffing box and controls;

•

snubbing unit BOP, grippers and controls;

•

coiled tubing unit BOP, stuffing box and controls;

•

landing string, subsea test tree and controls;

•

surface test tree, valves and controls;

•

rotating control device (RCD), operating choke and controls for managed pressure drilling (MPD) or under-balanced drilling (UBD);

•

subsea wireline riser system;

•

subsea workover riser system.

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3 Contents of a Well Examination Scheme 3.1

General requirements The general requirements of the well examination regulations are that the well operator must have a written well examination scheme in place for ensuring that the well is so designed and constructed, and is maintained in such repair and condition, 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 is reasonably practicable. The examination is intended to provide assurance that the well is designed and constructed properly and is adequately maintained. It is essential for the examination to demonstrate that the pressure containment boundary of the well is controlled throughout the well’s life cycle and that the pressure control equipment that forms part of the well is suitable for this purpose. The main aspects of the examination are likely to be: •

review of the anticipated sub-surface conditions at the proposed well location;

•

review of documentary evidence of well design;

•

review of documentary evidence of well integrity;

•

interview / discussion with well engineers responsible for planning and operations;

•

monitoring of operations reports / review of verification reports;

•

monitoring of production well monitoring / preventative maintenance;

•

review dispensations and change management for wells and well operations.

A balance needs to be struck between providing the well examiner with all the necessary information at an early stage, but not involving them in the decision making process.

3.2

Depth and extent of well examination The well examination scheme shall cover the well operator’s processes to design, construct, operate, maintain, suspend and abandon wells in compliance with the general duties of SCR 2015 and DCR. This should include (some well operators may use different names): •

well delivery process: –

casing design process and software;

–

test / completion string design and software;

•

management of change procedure;

•

well integrity management system:

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•

–

annulus monitoring;

–

wellhead / Christmas tree condition monitoring;

safety and environmental management system.

The well examiner should check that the well operators follow their internal processes during the design, planning, and operations stages of well operations. The well examiner should also review the assessment of sub-surface conditions that is required of the well operator and be satisfied that the sources of information are sufficient and appropriate. It is not within the well examiner’s remit to re-interpret the data. For wells in external waters, the well examiner must prepare a well examiner’s report for inclusion by the well operator in the well notification (and any material changes to the well notification) together with a description of the actions taken by the well operator in response to the report. The well operator must include with the well notification a statement made after considering the report by the well examiner that the risk management relating to well design and its barriers to loss of control are suitable for all anticipated conditions and circumstances. The well examiner should review the well operator’s operational plans concentrating on definition, installation, and testing of barriers throughout the well life cycle, including: •

•

•

drilling / testing / completion programmes: –

casing / wellhead – rating, design, centralisation, lockdown;

–

cement – placement, slurry design, planned tops;

–

pore / fracture pressures – mud weight, leak-off tests;

–

well barriers when removing BOP / installing Christmas tree;

–

suspension / abandonment arrangements;

intervention / workover programmes: –

management of operations;

–

barrier testing before and during well entry;

–

monitoring and control of intervention control panel;

well maintenance records.

The depth of examination should depend on the criticality of the operation and the hazards involved in the operations as assessed by the well examiner. For example, detailed examination should be done if: •

the operation is unusual for that well operator (e.g. first Christmas tree change-out);

•

the well conditions increase hazards (e.g. high-pressure reservoir);

•

the planned operations increase hazards (e.g. pressured hydrocarbons at surface); or

•

there are unusual management arrangements (e.g. coil tubing crew on well service vessel).

If a well needs specialist input or expertise (for example, deep-water or extended reach drilling) the well operator should ensure that this expertise is included in its well design and operations team. The well operator cannot rely on the well examiner to compensate for any lack of expertise in the wells team.

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High hazard wells may need specialist input or studies (for example casing design for deviated HPHT wells). These may be provided by the well operator or a competent third party. The well examiner will check that this process has been carried out and review the results of the studies. Well examination may need to review factors that are outside the well pressure containment boundary but may have an adverse impact on it, for example: •

state of seabed for jack-up foundations;

•

collision risk in shipping areas;

•

wellhead protection from fishing operations; or

•

confirmation that seabed surveys have been carried out, before and after operations.

During operations, the well examiner should review the well operator’s reports (including any change management / dispensation requests) and compare to: •

the well operator’s internal processes;

•

the plans and procedures for that operation; and

•

industry standards.

A checklist may be used to ensure all critical values are recorded and compared including:

3.3

•

casing setting depths;

•

weight / volume of cement pumped and estimated top of cement;

•

leak-off test / formation integrity test values;

•

mud weights; and

•

pressure test values and durations (e.g. casing, BOP, test string).

Examination through the well life cycle Well examination arrangements should cover the life cycle of the well beginning at the design stage and ending when the well is abandoned. The well examination scheme should define how often different types of wells should be examined at various stages in their life cycles.

3.3.1

Design Well examination should cover all aspects of the well design stage including: •

review of well design, casing design and work programmes;

•

check assessment of conditions below ground;

•

well operator’s process for checking suitability of materials; and

•

well operator’s process for checking suitability of equipment (especially for well control).

Critical elements of the design should be examined including: •

load cases / design factors considered during casing design;

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3.3.2

•

philosophy of pressure testing (e.g. durations, pressures); and

•

selection, installation, and testing of barriers.

Well construction (drill, test and complete) Well examination should monitor the well construction phase to ensure the well is constructed in compliance with previously examined design. Deviations or dispensations from policy or procedures plus management of change should also be monitored. The emphasis should be on reviewing the installation or testing of the pressure containment boundary such as:

3.3.3

•

casing and cement;

•

well barriers (e.g. fluid column); and

•

leak-off test / formation integrity tests.

Commission This phase often covers handing over operational responsibility for a well. Important factors include:

3.3.4

•

Any handover of responsibilities under the well examination scheme for that well. This is usually clear for a well on a production installation. It is less clear for a subsea well tied back to an installation operated by another company. The handover should include a definition of the pressure containment boundary for that well.

•

There may be a change in the well examiner, or the independent verification body may become responsible for carrying out the actions required by the well examination scheme.

•

There may be a change in well operator (e.g. from a well management company who was the well operator during the design and construction of the well).

Operate and maintain This phase covers planned operations, production or injection, on a completed well, including routine maintenance and condition monitoring. These operations should be included in the well examination scheme and will include such things as preventative maintenance of Xmas tree valves, and function and pressure testing of down-hole safety valves. Credit may be taken for activities carried out under an installation verification scheme. The well operator may have a well integrity management system and the well examination may consist of a review of the output from this system. There is a requirement to take account of changes in downhole conditions, downhole equipment and potential changes to well integrity (e.g. corrosion, erosion, failure of completions equipment or casing). The well examination scheme should cover wells where production or injection has stopped and the well is shut in without additional suspension barriers. The well examination scheme should explicitly cover these wells, describing what checks are carried out and which examination or verification body is responsible for reviewing the checks.

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3.3.5

Intervention and workover Workovers, interventions and wireline operations are subject to well examination. Well workover and intervention operations typically include well entries for maintenance and repair. The operational responsibility for the well may be handed over for these operations. The well examination scheme should cover the procedures and equipment used in these operations. Credit may be taken from the offshore installation verification scheme for well control equipment used in these operations. These operations should be notified to the OSDR (external waters) or the HSE (internal waters or onshore). For wells in external waters, routine and relatively low risk wireline operations from an installation may be subjected to a one-off well notification and well examiner’s report to the OSDR. These operations include: a. bailing; b. change-out of wireline set surface controlled subsurface safety valve (SCSSSV) or ambient valve, excluding initial setting of ambient valve; c. change-out of wireline electrical submersible pump (ESP) or hydraulic submersible pump (HSP); d. change-out of gas-lift valve; e. change-out of straddle assembly; f.

drift runs;

g. fishing with wireline, excluding fishing for wire requiring multiple runs; h. lock-out Tubing Retrievable-DHSV and run Wireline Retrievable-DHSV; i.

logging;

j.

punch tubing for the purpose of circulating annulus;

k. functioning sliding sleeve; l.

re-perforating reservoir;

m. replacement of DHSV with tubing plug; n. replacement of straddle with tubing plug; o. setting or recovering plug for water shut-off or zone isolation; p. setting or recovering tubing plug; q. setting or recovering pressure gauges; r.

tree change-out, if like for like.

These are based on the principle that they follow standard procedures, no tubing is run through the wellhead and the operation does not change the configuration of the well. In the event of a material change to the particulars submitted in a one-off notification, OSDR must be notified of the change. Operations not included in the original one-off notification may be added through notification of a material change, provided they are in the above list.

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To ensure that the one-off notification remains valid, it should be subject to periodic review. OSDR should be notified of the outcome of the review and advised of any material changes not previously notified. This material change is subject to well examination. Although the listed operations do not require further notification, they should be included in the weekly reports to the HSE.

3.3.6

Suspend All wells where activities or operations have been suspended before or after full construction should be included in the well examination scheme, including subsea wells and wells that have been purchased from another company.

3.3.7

Abandon Well abandonment plans, procedures and operations are subject to the well examination scheme. When the well has been permanently abandoned, it is no longer included in the well examination scheme. Well examination records must be kept at an address in Great Britain, notified to the OSDR / HSE, for a period of six months after the relevant scheme ceases to be current, e.g. after the well has been abandoned.

3.4

Reports from the well examination scheme The well examiner makes reports to the well operator about the examination carried out including any findings resulting from the well examination and any remedial action that may be required. The well examination reports begin with the receipt of well information and end after the termination of operations. Reports are issued in accordance with the well examination scheme. For wells in external waters, the well operator must include a well examiner’s report with the well notification and describe the actions that have been taken in response to this report. It is expected that these examination reports will be concise (essentially a one-page summary report) and should summarise what has been examined in respect of the planned operations, the findings and any recommendations from the examination and list any deviations from the standards described in the scheme. A reasonable timeframe should be available for the completion of examination work. The examiner may have questions in relation to the input documentation and an allowance should be made for providing follow-up data and for the examiner to respond to it. It should also be recognised that during the construction and operations / maintenance phases, examination may be a retrospective exercise. The well operator has primary responsibility for the safe management of day to day operations. The requirement to consult the well examiner must not prevent the timely implementation of proposed changes where necessary to prevent the unplanned escape of fluids. If an instantaneous material change to a well notification is required to ensure well integrity, it is acceptable to submit the well examiners report to OSDR as soon as possible after the material change has been submitted. Operations should not be suspended pending review by the examiner, especially where such a suspension may have detrimental safety implications.

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For wells in external waters, the well operator must also include a well examiner’s report with a summary of the actions taken to address any findings, with a notification of a material change to a previously submitted well notification. Again, it is expected that these examination reports will be concise. The examiner will record the examination in accordance with the examination scheme recording requirements through to completion of operations (e.g. checklists may be used to ensure all critical values are recorded and compared). Examination records will be kept by the operator as defined by the examination scheme. Operate phase examination reports, covering well integrity, are also required and these shall be described in the well examination scheme. Well examination records must be kept at an address in Great Britain, which has been notified to the OSDR / HSE, for a period of six months after the relevant scheme ceases to be current, e.g. after the well has been abandoned.

3.4.1

Resolving disputes The well examination scheme should describe the arrangements for resolving disputes between the well examiner and the well operator’s operations team. This should include arrangements for communicating examination findings to an appropriate level in the management system of the well operator. This should be the management level with sufficient authority to ensure that the action required, in light of the examination findings, is taken. If an issue remains unresolved, arrangements should be in place to escalate through the well operator’s management chain until the matter is resolved. The ultimate decision is the responsibility of the well operator.

3.5

Standards used in well examination The regulations do not specify against which standards the wells should be examined. However, the examination should be based on statutory requirements, industry standards, industry guidelines and the well operator’s own internal standards. It is part of the competency of the well examiner to examine the adequacy of the well design and operations against appropriate standards.

3.5.1

Well operator’s internal standards The well operator shall have internal standards and processes covering well design, well operations and well integrity. It is the responsibility of the well operator to ensure that the well examiner is provided with a copy of the internal standards. When the internal standards are revised, the well operator shall ensure that the well examiner is provided with revised standards. As a minimum, the well examination should check that all well designs and operations comply with the well operator’s internal standards.

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3.5.2

Industry standards The well operator’s internal standards may include references to a range of industry standards and guidelines applicable to wells and well operations. These are likely to be more detailed than company standards and cover specific parts of equipment or operations. These may have general application such as API and ISO standards, or more specific application such as the Oil & Gas UK Guidelines for High Pressure, High Temperature Wells. The well examiner should check that relevant standards are complied with during the examination of the well design and may review the well design against the detailed standard(s).

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4 Limits of the Well Examination Scheme 4.1

General duty of the well operator Regulation 13 of DCR places a general duty on 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 health and safety of persons from it or anything in it, or in strata to which it is connected, are as low as is reasonable practicable. Well examination does not take away or lessen these well operator responsibilities. Well examination is not a part of a well operator’s well design, construction or maintenance processes. It is an independent check of the results of these processes.

4.1.1

What is excluded from a well examination scheme It is not anticipated that well examination schemes will rely on physical examination of wells. A well examination scheme based on documents and discussions with onshore personnel will generally be sufficient. Operational performance and efficiency aspects of well operations are not part of the well examination scheme.

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5 Administration of a Well Examination Scheme 5.1

Information, instruction, training, and supervision Well operators have responsibility for the effectiveness of their well examination schemes. It cannot be left to the well examiner. All personnel involved in the well life cycle should be aware of the well examination scheme and any duties they have under it. Training in the well examination scheme may be provided for personnel who have defined roles in the well examination scheme: •

well engineers (e.g. drilling, testing, production, interventions);

•

drilling or well services supervisors (plus key personnel employed by drilling and well service contractors); and

•

production personnel, operations and maintenance staff / contractors.

The training should include clear guidance on the type of information to be provided to the well examiner and to be filed within the well examination scheme. It should cover how to respond to reports generated by the well examiner.

5.2

Keeping records The arrangements in writing (the well examination scheme) should be kept at an office in Great Britain, notified to the OSDR or HSE, as appropriate. Old versions should be kept at the address for six months after revision. Any reports produced by the well examiner should be kept for at least six months after they cease to be current (that is after abandonment of the well).

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6 Interface with Installation Verification When a well is connected to an offshore installation, there may be an overlap between the well examination scheme and the verification scheme for that installation. The duty holder(s) should ensure there are no gaps between the well examination and verification schemes. Work done to meet the requirements of the well examination scheme may contribute to the installation’s verification arrangements, and vice-versa. The sharing of reports generated by well examination schemes and installation verification schemes is considered to be good practice.

6.1

Boundary of well examination scheme The well operator’s well examination scheme covers everything within the well “pressure containment boundary”. This includes the downhole pressure-containing equipment and the pressure-containing equipment on top of the well such as blowout preventers (BOP) or Christmas trees, but excludes well control equipment downstream that can be isolated from the well by valves. Examples of where the well (and therefore the well examination scheme) ends are: •

above the top BOP in the BOP stack and outside the choke and kill valves;

•

downstream of swab and production wing valves of the Christmas tree;

•

at the top of the stuffing box of a wireline BOP;

•

above the rotating control device (RCD) and downstream of the operations choke for managed pressure drilling (MPD) or under-balanced operations (UBO) equipment;

•

downstream of swab and production wing valves of a surface test tree;

•

above the wellhead (or conductor) and the top barrier in a suspended well.

Well examination schemes do not include: •

well test flowline and downstream equipment (e.g. choke, heater, separator);

•

rig gas handling equipment (e.g. diverter, mud gas separator, vent lines); or

•

returns handling equipment for MPD or UBO.

This equipment is likely to be classed as safety and environmentally critical elements, and so should be covered by the installation verification scheme.

6.2 6.2.1

Interface with verification over the well life cycle Well design The verification work carried out by the installation duty holder (e.g. the drilling contractor for mobile drilling rigs) may be taken into account as part of the demonstration of suitability of well control equipment. The well operator may also carry out an independent audit of the equipment.

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6.2.2

Well construction The verification check which is carried out by the installation duty holder on temporary well control equipment may be taken into account as part of the demonstration of suitability of well control equipment. The well operator is responsible for providing adequate information to the installation duty holder so that they can fulfil their statutory responsibilities including verification.

6.2.3

Commission It is important to clarify the limits and responsibilities between well examination and installation verification schemes at this point because operational responsibility for the management of the well may change. There is no requirement for work to be duplicated under the schemes but it is vital that there are no gaps.

6.2.4

Operate and maintain Modifications to the wellhead and Christmas tree and the “in service” maintenance and testing regime will normally be part of the installation verification scheme if the well is considered a safety and environmentally critical element of the installation. Any third-party safety and environmentally critical equipment used in these operations may also be covered by the installation verification scheme. This work may be cited in the well examination scheme. There is also a requirement to take account of downhole changes, equipment, and other potential changes (e.g. corrosion, erosion, failure of completions equipment or casing).

6.2.5

Intervene and workover The verification check which is carried out by the installation duty holder on temporary well control equipment may be taken into account as part of the demonstration of suitability of well control equipment. The well operator is responsible for providing adequate information to the installation duty holder so that they can fulfil their statutory duties including verification.

6.2.6

Well abandonment A permanently abandoned well is no longer a safety and environmentally critical element and so will not be included in the installation verification scheme.

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7 Additional Well Examination Requirements of SCR 2015 for Wells in External Waters Well examination requirements are detailed in eight regulations and four schedules of the SCR 2015 regulations. A list of these regulations and schedules is provided in appendix B. The main additional requirements of these regulations with respect to well examination are: •

The well operator must include with the well notification sent to OSDR a statement made after considering reports by the well examiner, that the risk management relating to well design and its barriers to loss of well control are suitable for all anticipated conditions and circumstances.

•

A well examiner’s report shall be included in a well operator’s notification of well operations and notifications of material changes.

•

On production installations, some routine wireline operations, which are considered relatively low risk, may be subject to a one-off well notification and well examiner’s report.

•

Well operator’s well examination scheme to be described in the well operator’s Safety and Environmental Management System.

•

Safety critical elements (SCE) have been replaced with safety and environmentally critical elements (SECE).

•

Schedule 9 (particulars to be included in a notification of well operations) requires additional information in comparison to Schedule 6 of SCR 2005.

•

Well notifications are submitted to the OSDR (rather than the HSE) acting as the Competent Authority. The OSDR is a partnership between the HSE and BEIS.

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Appendices A References Health and Safety Executive (HSE) regulations and guidance 1

SCR 2015

The Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015

2

SCR 2015 Guidance

The Offshore Installations (Offshore Safety Directive) (Safety Case etc.) Regulations 2015 - Guidance on Regulations L154

3

DCR

The Offshore Installations and Wells (Design and Construction, etc.) Regulations 1996 SI 1996/913; ISBN 0 11 054451 X

4

DCR guidance

A guide to the well aspects of the Offshore Installations and Wells (Design and Construction, etc.) Regulations 1996 – L84 Second edition 2008 ISBN 978 0 7176 6296 8

5

Licensing Regulations

The Offshore Petroleum Licensing (Offshore Safety Directive) Regulations 2015

6

SCR 2005

The Offshore Installations (Safety Case) Regulations 2005 SI 2005/3117; ISBN 0 11 073610 9

7

SCR 2005 Guidance

A guide to the Offshore Installations (Safety Case) Regulations 2005 – L30 Third edition 2006; ISBN 978 0 7176 6184 8

8

ALARP “at a glance” HSE internet guidance (accessed October 2011) http://www.hse.gov.uk/risk/theory/alarpglance.htm Oil & Gas UK Documents

9

Guidelines for Well Operators on Competency of Well Examiners. Issue 2. August 2017 ISBN: 1 903 004 89 6 http://www.oilandgasuk.co.uk/publications

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10

Guidelines for High-Pressure, High-Temperature Wells Issue 1. October 2016 ISBN: 1 903 004 77 2 http://oilandgasuk.co.uk/product/guidelines-forhigh-pressure-high-temperature-wells-october-2016up002/

11

Well Life Cycle Integrity Guidelines Issue 3: March 2016 ISBN: 1 903 004 71 6 http://oilandgasuk.co.uk/product/well-life-cycleintegrity-guidelines-issue-3-march-2016/

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B SCR 2015 Parts Relevant to Well Examination The paragraph numbers refer to HSE publication, The Offshore Installations (Offshore Safety Directive) (Safety Case etc) Regulations 2015 - Guidance on Regulations - L154 Introduction Guidance paragraphs: 23, 57 and 59. Regulation 2 - Interpretation Interpretation “well examination scheme”; “well examiner”; “independent and competent”. Guidance paragraph 99. Regulation 8 – Safety and environmental management system Description of well examination scheme (6)(b). Guidance paragraphs: 138, 140 and 141. Regulation 9 – Establishment of verification scheme Guidance paragraphs: 151 and 159. Regulation 11 - Establishment of well examination scheme Guidance paragraphs: 171 to 178. Regulation 12 - Other provisions as to well examination schemes Guidance paragraphs: 179 to 183. See also Schedule 4 part 2. Regulation 13 – Description of verification scheme and well examination scheme Guidance paragraphs: 184 to 188. Regulation 21 – Notification of well operations Guidance paragraphs: 253, 256, 259, 260, 262 and 269. See also Schedule 9. Regulation 27 – Keeping of documents Regulation 27(4), guidance paragraph: 310. Schedule 4 Part 2 - Matters to be provided for in a well examination scheme Guidance paragraphs: 405 to 417. Schedule 6 – Particulars to be included in a safety case for the operation of a production installation

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Guidance paragraphs: 438, 440 and 441. Schedule 7 – Particulars to be included in a safety case for a non-production installation Guidance paragraphs: 480. Schedule 9 - Particulars to be included in a notification of well operations Guidance paragraph: 549.

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C Background to these Guidelines Issue 2 of these guidelines has been prepared in response to the SCR 2015 Regulations which were introduced in response to the EU Directive on the safety of offshore oil and gas operations (2013/030/EU). They are a revision of Issue 1 of the guidelines which were published in November 2011. In May 2010, the UK offshore oil and gas industry set up the Oil Spill Prevention and Response Advisory Group (OSPRAG) to review the UK’s well control practices and oil spill response capability following the Macondo incident in the Gulf of Mexico on 20 April 2010. One of OSPRAG’s four review groups, the Technical Review Group (TRG), carried out a review of industry practices and procedures relating to well examination, verification, and primary well control; blowout preventers; and competency, behaviours, and human factors. The unanimous conclusion was that there was a high degree of confidence in the UK regulatory regime and recognition that it drives the right health, safety and environmental behaviours. Several recommendations to the industry were proposed which were primarily based upon the best practices observed during the TRG review. For more information, please refer to the OSPRAG final report - available from Oil & Gas UK. The Wells Forum (formerly the Well Life Cycle Practices Forum (WLCPF)) was set up in December 2010 by Oil & Gas UK as a vehicle for implementing the TRG recommendations and as a permanent industry forum in which well-related issues can be identified and discussed. One of the core objectives of the Wells Forum is the maintenance and communication of guidelines that define Good Industry Practices and Best Available Techniques for wells and well operations to help the UK upstream oil and gas industry meet UK and European Union requirements The Wells Forum is the interface of choice for the regulator to engage with the UK offshore industry on well-related matters. The Wells Forum has representatives from over 30 different operators and well management companies, and over 60 companies have been involved in the various workgroups and review cycles.

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London Office: 6th Floor East, Portland House, Bressenden Place, London, SW1E 5BH Tel: 020 7802 2400 Fax: 020 7802 2401 Aberdeen Office: Exchange 2, 3rd Floor, 62 Market Street, Aberdeen, AB11 5PJ Tel: 01224 577250 Fax: 01224 577251 [email protected] www.oilandgasuk.co.uk ISBN: 1 903 004 88 8 Copyright © 2017 The UK Oil and Gas Industry Association Limited trading as Oil & Gas UK

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