Decommissioning of offshore oil and gas installations and pipelines is regulated by the Petroleum Act 1998. Under the Act the Secretary of State is empowered to serve notice on a wide range of persons (in the first instance this would include parties to Joint Operating Agreements in respect of installations and owners in respect of pipelines) which either specify the date by which a decommissioning programme for each installation or pipeline is to be submitted or, as is more usual, provide for it to be submitted on or before such date as the Secretary of State may direct. Decommissioning Liabilities contain further details on this process.

A decommissioning programme sets out the measures proposed to be taken in connection with the decommissioning of disused installations and/or pipelines and will describe, in detail, the methods employed to undertake the work. In some cases this process can cover a wide range of activities, such as radioactive material handling, removal of debris from the seabed and environmental monitoring of the area after removal of the installation. It is the Department s aim that decommissioning programmes are considered in a transparent manner. As a result, other Government Departments/Agencies, Non -Governmental Organisations, members of the public and other bodies are given the opportunity to comment on the proposals set out in a programme. Decommissioning programmes lists any programmes that are currently under consideration.

At the first Ministerial Meeting of the OSPAR Commission (Commission for the Protection of the Marine Environment of the North East Atlantic) a binding Decision was agreed which set the rules to be applied to the disposal of offshore installations at sea. Under the Decision, there is a prohibition on the dumping and leaving wholly or partly in place of offshore installations. The Decision recognises that there may be difficulty in removing the 'footings' of large steel jackets weighing more than 10,000 tonnes and in removing concrete installations. As a result there are derogations for these categories of installations if the internationally agreed assessment and consultation process shows that leaving these in place is justifiable. The full OSPAR Decision 98/3 is available from the OSPAR web site at The UK has submitted a paper to OSPAR on the review of derogation categories (OIC 03/2/1-E) - further details are available from the OSPAR website under Meetings and Documents

Further details on the decommissioning process, including the role and content of a decommissioning programme, are available in the 'Guidance Notes for Industry on the Decommissioning of Offshore Installations and Pipelines under the Petroleum Act 1998 . These Guidance Notes can be viewed and downloaded here. Alternatively, hard copies can be requested on-line at quoting reference URN 00/915. A list of all the installations on the United Kingdom Continental Shelf and their current status is available from the OSPAR website at under Meetings and Documents (reference:OIC 03/02 02-E, Annex 1)".

Detailed analysis regarding estimated decommissioning dates is shown in the following diagram. The information will be reviewed on a regular basis and is subject to change. No further breakdown of the diagram is available as this is treated as "commercial in confidence".

Further information, including the presentation by Keith Mayo, (Head of the Offshore Decommissioning Unit in the UK) at the Bergen Decommissioning

Conference on the 25th - 26th February 2003 is shown in the following documents:

The issue of how best to deal with drill cuttings at the decommissioning stage is receiving detailed consideration at present. Drill cuttings consist of rock fragments, contaminated in some instances with the drilling mud which was used to lubricate the drill bit in drilling operations. They are created when a hole is drilled through rock to reach oil and gas trapped below. At the rig, the cuttings are separated from the drilling mud, and in some cases, these cuttings have then been discharged to the seabed where they can accumulate around the base of installations and at remote subsea drilling locations, to form what is know as drill cuttings piles.

A Joint Industry Project (JIP) project on drill cuttings was recently undertaken by the United Kingdom Offshore Operators Association (UKOOA). The aim of this study was to identify the best environmental practice and the best techniques available for dealing with these cuttings piles. This study has contributed to the ongoing debate within the OSPAR Commission on what approach should be adopted. Further details are available from the UKOOA website at: The UK has submitted a paper to OSPAR on "Drill Cuttings Piles - Next Steps" (OIC 03/7/4-E) - further details are available from the OSPAR website under Meetings and Documents.

Product development and market base aspects

The Offshore Decommissioning Unit is a regulatory branch and, although interested in this aspect which will hopefully lead to improved decommissioning outcomes, it is not our area of responsibility. Our colleagues in DTI Energy Group's Energy Innovation and Business Unit (EIBU) lead on this matter and queries of this nature should ideally be directed to them.

The contact in EIBU is Mr Ian Knox on 01224 254096 or via e-mail at

Decommissioning liabilities

The decommissioning of offshore oil and gas installations and pipelines is regulated under Part IV of the Petroleum Act 1998. Section 29 of the Act enables the Secretary of State to serve notices on a wide range of persons, including Licensees, requiring the submission of a costed decommissioning programme at such time as he may direct. Under the Act any new licensees will become jointly and severally liable along with existing Licensees for the submission and execution of a decommissioning programme.

For further information on the decommissioning process and the liabilities of section 29 notice holders please refer to the DTIs Guidance Notes for Industry on the Decommissioning of Offshore Installations and Pipelines, available here, or by contacting the DTIs Offshore Decommissioning Unit in Aberdeen (Tel: 01224 254021).

Copies of two recent papers that DTI prepared for Industry, which explain in more detail the process we use when considering whether or not to withdraw a Section 29 notice following licence transfer, and the associated considerations of decommissioning security, can be viewed by clicking on this links below.

Guidance notes

Decommissioning of offshore installations and pipelines under the Petroleum Act 1998

The Government's Guidance Notes for Industry on the Decommissioning of Offshore Installations and Pipelines were published in final form on 21 August 2000. This followed an extensive public consultation exercise in 1999 during which comments were received from the oil and gas industry and other interested parties.

In line with the Code of Practice on Government Information, all the comments received during the consultation period are available for inspection at the Information & Library Services, 1 Victoria Street, London (Tel. 020 7215 6226) and the DTI Office, Atholl House, 86 -88 Guild Street, Aberdeen (Tel. 01224 254029).

The Guidance Notes, which are designed to help companies through the process of seeking Government approval for their decommissioning proposals, may be viewed and downloaded from this website or paper copies may be requested from the DTI's Offshore Decommissioning Unit in Aberdeen (Tel. 01224 254029).

Guidance Notes (Word 97, 1.8 MBytes)

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During the course of field life, pipelines/parts of pipelines may be taken out of use for example due to corrosion. When this happens, the Secretary of State has the option of immediately calling for a full decommissioning programme under the Petroleum Act 1998. However, this is not always considered an appropriate option and it has therefore been agreed that consideration will be given to handling suitable pipelines, under an Interim Pipeline Regime.

The Interim Pipeline Regime is intended to ensure that out of use lines are covered by an appropriate surveying and maintenance regime from the point when they are taken out of use until approval of the formal decommissioning programme, which is usually at the end of field life. It should be noted that any interim solution should not prejudice the ultimate decommissioning fate of that line.

The Department expects the operator to submit details of an out of use pipeline /part as soon as they are aware of it . At present the paper form attached may be completed and sent to DTI via normal post or email. However when the UK Oil Portal is available on the OG web site later this year, the operator should submit details on-line using their portal account.

In preparation for the portal, DTI is conducting a n initial survey to identify currently disused pipelines and operators should complete the on-line survey form available on the OG web site at: . Please send an email request to to obtain an account and a password enabling you to complete the survey form .If an Operator does not have access to the internet they should complete the paper form which is attached as a word document and either e-mail or post it to the DTI at Atholl House, 86 -88 Guild Street, Aberdeen AB11 6AR.

If a formal decommissioning programme is not immediately considered appropriate, the information given in the survey form will be circulated to other government departments including the Department of Environment, Food and Rural Affairs (DEFRA), the Scottish Executive Environment and Rural Affairs Department (SEERAD), and the Health and Safety Executive (HSE).

Following receipt of any comments from these organisations and our own consideration of the information, we will either confirm that:

Following confirmation that a pipeline has been accepted under the Interim Pipeline Regime, we would continue to monitor the condition of the pipeline by asking the Operator to inform us of the date of any future surveys, the findings of these surveys and any remedial action proposed as a result.

Draft programmes Under Consideration

Field Name Field Operator Status Main Points of Programme Website Details (if known)
N W Hutton BP exploration Operating Company Limited Discussions with DTI are at an early stage. First draft of the decommissioning programme is expected at the end of 2003.
Brent Redundant Faculties (Brent Flare/ Brent Anchor Blocks Shell UK Limited First draft of decommissioning programme due July 03

Back | Title | Table of Contents
Appendix 1 | Appendix 2 | Appendix 3 | Appendix 4 | Appendix 5 | Appendix 6 | Appendix 7 | Appendix 8 | Appendix 9
Appendix 10 | Appendix 11 | Appendix 12 | Appendix 13 | Appendix 14 | Appendix 15 | Appendix 16 | Appendix 17
Index Map | Plate 1 | Plate 2W | Plate 2E | Plate 3W | Plate 3E | Plate 4W | Plate 4E | Plate 5 | Plate 6
Plate 7 | Plate 8W | Plate 8E | Plate 9W | Plate 9E | Plate 10W | Plate 10E | Plate 11 | Plate 12 | Legend