Decommissioning Index

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Legislative framework International legislation The process of decommissioning is very strictly regulated by international, regional and national legislation. These regulate both the removal of installations (primarily concerned with safely of navigation and other users of the sea) and disposal (primarily aimed at pollution prevention). There is a framework of international conventions which, in turn, influence national legislative requirements. The primary ones are noted below: UNCLOS: The United Nations Convention on the Law of the Seas, 1982 (UNCLOS), superseded the 1958 Geneva Convention and Article 60 (3) permits the partial removal of structures provided that IMO criteria are met. This first came into force in 1994 and was ratified by the UK in 1997.   London(Dumping)Convention: The 1972 London Convention (and the subsequent 1996 Protocol) made the provision of generic guidance for any wastes that can be dumped at sea. New guidelines were adopted in 2000, to specify different classes of waste, including platforms and other man-made waste.   IMO: The International Maritime Organisation (IMO), headquartered in London, sets the standards and guidelines for the removal of offshore installations worldwide. The 1989 IMO Guidelines require the complete removal of all structures in water depths less than 100m and weighing less than 4000 tonnes. Those in deeper waters can be partially removed, leaving a minimum 55m of clear water for the safety of navigation. All structures installed after 1st January 1998 must be designed so as to be feasible for complete removal. Many of these IMO guidelines are superseded by OSPAR 98/3, but some remain relevant: - any disused installation, structure or part thereof, which projects above the sea (i.e. the topsides) should be adequately maintained; - an unobstructed water column of at least 55m must be provided above the remains of any partially removed installation to ensure safety of navigation; - the position, surveyed depth and dimensions of any installation not entirely removed should be indicated on nautical charts and any remains, where necessary, properly marked with aids to navigation; - the person responsible for maintaining the aids to navigation and for monitoring the condition of any remaining material should be identified; - it should be clear where liability lies for meeting any future claims for damages. OSPAR: In 1992 the Oslo and Paris Convention for the Protection of the Marine Environment of the North East Atlantic (OSPAR) was drawn up to replace the 1972 Oslo Convention on dumping from ships and the 1974 Paris Convention on discharges from land. There are 16 contracting parties, including the UK. Until June 1995, the OSPAR Convention permitted, under certain circumstances, the disposal at sea of parts or all of disused offshore installations; but this changed after the Brent Spar affair. In July 1998, at the OSPAR Ministerial meeting in Sintra, Portugal a new regulatory framework was drawn up which no longer permits disposal of offshore structures at sea (except for exceptional circumstances). Decision 98/3 came into force in February 1999 and requires: - The topsides of all installations to be removed to shore; - All sub-structures or jackets weighing less than 10,000 tonnes to be completely removed to shore for reuse, recycle or disposal on land; However, in addition to these stipulations the legislation provides, on a case-by-case basis, a mechanism of derogation where there may be practical difficulty in removing installations, i.e. the footings of large steel platforms weighing over 10,000 tonnes, the concrete gravity based platform sub-structures, or concrete anchor bases and other structures with significant damage or deterioration (which would prevent removal). The decision for granting derogation ultimately lies with the UK government, following technological justification and appropriate consultation with other OSPAR Contracting Parties. These rules are enshrined in UK legislation through the Petroleum Act 1998 (but do not apply to pipelines). Every three years after 1999, in light of the experience of relevant research and the exchange of information, the OSPAR Commission reviews the criteria for future derogations. However, this was not changed in 2002 or 2005. The next review is planned for 2008.   UK regulations and due process The Petroleum Act 1998 regulates decommissioning of oil and gas installations and pipelines on the UKCS. Under the 1998 Act (which superseded the 1989 Petroleum Act) a decommissioning programme should contain an estimate of the cost of the measures proposed, specify the times within which those measures are to be taken and, where an installation or pipeline is to remain in position or be only partly removed, include provision for maintenance where necessary. It is recognised that, where appropriate, a decommissioning programme will deal with both removal and disposal of an installation or pipeline. Under the act the relevant parties (operators and owners, as designated by the DECC through serving Section 29 Notices) are joint and severally responsible for submitting an appropriate decommissioning programme to the Secretary of State within a specified time frame. Section 34 of the Petroleum Act also stipulates that the DECC can recall any previous owner of the installation to be responsible for the costs associated with the decommissioning programme. These programmes are available for public scrutiny and undertake a period of consultation to receive (and address) comments from other government departments/agencies, statutory consultees (i.e. fishing organisations, non-governmental organisations, members of the public and other bodies). Prior to submission, operators (on behalf of joint-venture owners) will need to undertake studies, verification inspections and option assessments to include as justification for the proposed decommissioning programme. It then passes through the stages detailed in the next section. The industry and DECC (previously BERR & DTI) commissioned the Policy Studies Institute, PSI, to develop a methodology that applied sustainable development principles to this options assessment process. The resultant report can be viewed by clicking here.   The decommissioning programme approval process The DECC Guidance Notes for Industry – “Decommissioning of Offshore Installations and Pipelines under the Petroleum Act 1998”, provides a guide to the decommissioning process, and has recently been revised to include the process for derogation application under OSPAR 98/3. These guidance notes were recently updated following the amendments to the Petroleum Act introduced by the Energy Act 2008. The Introduction provides a simplistic description of the main stages involved in the implementation of a decommissioning project. A more complete breakdown of the procedure is described below. Six main stages to the process can be identified: Fig: The six main stages in the decommissioning process. Souce: DECC decommissioning guidance notes for Industry The flow diagram below summarises these stages; in addition the timing of activities related to OSPAR derogations cases are included. Fig: A breakdown of a typical UKCS Decommissioning Process Stage 3, “consultations with interested parties and the public” is covered more fully under the section "Commercial perspective" In addition, the Oil & Gas UK environmental legislation website provides a detailed breakdown of the consents required and actions arising at each stage of the decommissioning process for installations and pipelines, as well as for well suspension and abandonment. The DECC guidance notes state that a programme may deal with the decommissioning of all of the facilities located on a field or part of the facilities, including a single installation or pipeline. The precise content of a programme may vary according to the circumstances. However, the following sections are likely to be necessary in most cases: Introduction Executive summary Background information Description of items to be decommissioned Inventory of materials Removal and disposal options Selected removal and disposal option Wells Drill cuttings Environmental Impact Assessment (EIA) Interested party consultations Costs Schedule Project management and verification Debris clearance Pre- and post-decommissioning monitoring and maintenance Supporting studies In addition, to approve a decommissioning programme, the following will also need to be obtained as appropriate: Confirmation that the requirements of the Coast Protection Act 1949 have been satisfied; Acceptance of an Abandonment Safety Case under the Offshore Installations (Safety Case) Regulations 2005 (installations only); Fulfilment of notification requirements to Health and Safety Executive (HSE) under regulation 22 of the Pipeline Safety Regulations 1996; Any environmental consents or permits required during decommissioning activity; including Parts I and II of the Food and Environmental Protection Act 1985; Approvals for the trans-boundary shipment of waste, including authorisation under the Radioactive Substances Act 1993, and; Approval of a well abandonment programme in accordance with the obligation contained in the petroleum production licence. Where appropriate, consideration of the draft decommissioning programme will run in parallel with: Consideration by DECC Licensing and Consent Unit Field Teams of any Cessation of Production (COP) document (the procedures for submitting an application for COP are set out in the DECC's ‘Guidance Notes on Procedures for Regulating Offshore Oil and Gas Field Developments’ which can be viewed on the DECC's Oil & Gas Website); Consideration by the HSE of the Abandonment Safety Case; Consideration of any environmental permits or consents, and; any onshore disposal consents or licences which may be necessary, including any trans-frontier shipment of waste issues; The following approach will be taken in considering the decommissioning of pipelines on the UKCS: Decisions will be taken in the light of individual circumstances; The potential for reuse of the pipeline in connection with further hydrocarbon developments should be considered before decommissioning together with other existing projects (such as hydrocarbon storage). If reuse is considered viable, suitable and sufficient maintenance of the pipeline must be detailed; All feasible decommissioning options should be considered and a comparative assessment made; Any removal or partial removal of a pipeline should be performed in such a way as to cause no significant adverse effects upon the marine environment; Any decision to leave a pipeline in place should have regard to the likely deterioration of the material involved and its present and possible future effect on the marine environment; Account should be taken of other users of the sea. Last updated 14th May 2009