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The objective of this series of papers is to address the pressing issues surrounding the concept of abandonment of Northern North Sea offshore production facilities and structural steel jackets. For many operators there is a notional idea that when you are finished with an offshore production facility and structural steel jackets, they merely sails away over the horizon never to be seen or heard of again, but the real world dictates otherwise. For those that operate today in the Northern North Sea there is perhaps a uniqueness in character related to the design, fabrication, installation and operation of these Northern North Sea offshore production facilities. Approaching now for many the reality of abandonment, removal and disposal of these facilities, the oil and gas industries must now also recognise that unique methodology requires to be developed for implementation to overcome this daunting task of abandonment. Innovative and lateral thinking being employed by those companies and individuals who have risen to take up the challenge to achieve the goals and objectives, developing the ultimate solution to this enormous problem facing the oil and gas industry today. Many common aspects and activities exist for operators to undertake jointly during the planning, engineering and the various implementation stages for this ultimate episode in field life. "GOING WHERE NO OTHER HAS GONEBEFORE" Commendable words of introduction one might say! but how does one go about this planning exercise, being creative and having lateral thinking, receive participation from other operators within this industry to achieve a: " SAFE AND COST EFFECTIVE DISPOSITION FOR SUCH A FACILITY" The Oil and Gas industry until now has been rather slow and reluctant to respond to the idea that abandonment is right around the corner. A question that has been so prevalent in recent days, "WHY PLAN"? "Just because I never lead the industry in such circumstances, does not mean I am not responsible for planning them all well" A deliberate Abandonment Plan is the most essential tool that must be developed at the outset of the abandonment project, ensuring that you have defined clearly your goals and objectives to produce a safe and cost effective disposition for the offshore production facilities and structural steel jacket. Planning allows for abandonment projects to :-Set out the strategy, philosophy, goals and objectives for the abandonment programme.Identify the requirements of the various legislation that must be adhered too.Identify the potential hazards, safety and environmental issues to be resolved.Identify the cost drivers.Communicate to your management the magnitude of the potential problems that must be overcome.Communicate to the relevant government departments the prospective options under consideration and the potential consequences Planning may be half the effort required to accomplish the goals and the objectives of the abandonment project, but it is only a fraction of the ultimate cost. Through careful and detailed planning exercises an opportunity exists to save millions of pounds that could be better invested in the development of new oil and gas fields.

The cleaning of the process and utility equipment and systems forms part of the underlying strategy of planning and implementation. You will have observed from the thrust of these papers that planning is the first essential element to a successful project. A prerequisite to good planning is establishing the goals and objectives at the very outset of the Abandonment Planning. These goals and objectives must be measurable against pm-established criteria so that the project can be evaluated to establish the level of success. Good planning can be viewed as a series of hurdles that one must clear to achieve the pre-set goals and objectives. Understanding of the legal, safety, environmental and legislative requirements allows the perimeters and constraints to be established before the for the final implementation of the, "CLEANING OF PROCESS AND UTILITY EQUIPMENT AND SYSTEMS " activities. The very subject of "CLEANING OF PROCESS AND UTILITY EQUIPMENT AND SYSTEMS" that may be considered straight forward, because some of these activities often form part of the normal platform operations performed from time to time on these systems. Before implementation of these activities, there must be an understanding of the ground rules and terminology used together with the resultant implications. A question that demonstrates the inherent problems, what does the term "Clean" mean? A limited list has been compiled to give some examples of what the dictionary defines the term clean to be ;NOT DIRTY - UN-POLLUTEDDECONTAMINATED - STAINLESSUNCONTAMINATED - SPOTLESSVIRGIN - UNSTAINEDUNADULATERATED - STERILE Liaison with Government departments during recent planning activities established a consensus for understanding the term "Clean"so that unreasonable expectation with regards to the level of cleanliness would not be greater than that which is practicable. THE DEFINITION OF "CLEAN" Clean shall mean in this context free from hydrocarbon oils and gasses, sediments and reservoir contaminants, achieved by power washing with detergents and mechanical cleaning devices. LEGISLATION GOVERNING HAZARBOUS WASTES The International Commission for Radiological Protection (ICRP) aim is to, "prevent the detrimental no stochastic effects and to limit the probability of stochastic effects to such a level as deemed acceptable ". This is based on the recommendation of the ICRP published in 1977.No practice shall be adopted unless its introduction produces net benefit.All exposures shall be kept as low as reasonably achievable, economic and social factors being fully taken into account.The dose equivalent to individuals shall not exceed the limits recommended for the appropriate circumstances by the commission. These recommendations were revised in 1990 and will appear as British Legislation in 1995. IONISING RADIATION REGULATION 1985 Under the Ionising Radiation Regulation the operator must notify the Health and Safety Executive (HSE) and provide such information on the proposed abandonment of an offshore production platform. Information will include but not be limited to the following;Working methodology statement.Restriction to exposure.Dose limits.Designated control areas.Designation of classified personnel.Appointment of radiation protection advisorsSupervisors and procedures.Contractors and/or sub-contractors.

This final paper in the series deals specifically with the reconstruction and disposal of Offshore Production Platforms. Considerable time has been spent working in such an environment that has been fraught with many difficulties, where efforts to get both companies and individual excited about the prospects of Platform Abandonment. One perhaps can appreciate the dilemma that exist where employees understand that their career that is on the line and prospects for future employment are low, standard of living will degenerate through time, overall aspiration for life itself has greatly diminished. For the operator, owners and share holders the prospects are not any better, the loss of an asset, loss of essential cash flow, loss of position as a market leader, loss of dividends and a major demand on capital being expended on a project that brings no financial return in the short term. There are many negatives issues to be addressed and overcome that the positives, if there are any are not easily detected or appreciated. In the first paper some effort was made to highlight the uniqueness in character in approach that was necessary to the whole subject of Platform Abandonment. Innovative and lateral thinking, surely these are the process that all good engineers utilise when approaching new frontiers and future challenges. Unfortunately that is not the case, so often the working environment is one of stereo type, having tunnel vision focusing only on the negative effect, rather than standing back and considering the positive issues and in doing so we truly miss the great opportunities to be market leaders. "The oil and gas industries are entering a new strategic environment where the old values and methods of doing business are no longer acceptable". To establish a way forward both for Amoco and perhaps in some generic way for the industry as a whole, feasibility studies were undertaken to understand the Legislation and Environmental requirements, identify possible options, development of criteria for the evaluation process ensuring that elements such as risk, safety, environment, compliance with current legislation, technology, liabilities and financial exposure, and synergy with other operators considering platform abandonment's. The aim established at the outset of these studies was; "To undertake a critical assessment of every conceivable abandonment option that is available after production has ceased and process and utility systems have been cleaned, focusing on options for total removal, partial removal, toppling and disposal". What options are available for offshore platform abandonment? Depending from what view point you consider this whole problem, some have said there is only, "ONE" but realistically there are many options that must be considered and evaluated in great detail ensuring that the variances and cost drivers are identified and understood. Many of the offshore platform in the UKCS have several Participants, Co-ventures or Partners having different aspirations, Company Profiles, Values, Financial Commitments etc. but at the end of the day when the Operator applies to the DTI for approval to abandon an offshore production platform there must be, "Full Agreement" by all parties involved.