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Abstract One of the principle constraints to successful fracturing and stimulation, outside North America and a few select regions; remains the very poor QA/QC that is unfortunately the industry yardstick in low volume areas. This paper will describe a rigorous approach to the operational QA/QC which allows an operator to: provide assurance on the ability to effectively perform a treatment, maximise the opportunity for a successful intervention, ensure efficient delivery of data and minimise the overall costs. This paper will outline a suite of approaches which are both step-wise and encompass various operational stages such as contracting, pre-frac planning, frac operational execution and post-frac reconciliation. A number of the key considerations (in each of these areas) will be described in further detail, along with all of the necessary supporting tools, check-lists and recommendations as required. The paper will go on to describe examples of start-up operations which have actually benefitted from the application of this approach and will describe the potential pitfalls and outcomes which would have resulted, if the QA/QC regime had not been rigorously followed. Finally, the paper will describe the importance of the relationship which is developed, a priori as part of operational planning between the operator and the service company, and the impact that this can have on the outcome. The industry is littered with tight-gas exploration and appraisal programmes that have been aborted or curtailed, due to inadequate stimulation QA/QC and the poor results which they subsequently provide. All too readily, the formations themselves are held responsible for the lack of ability to stimulate and/or the poor subsequent production performance. Such poor performance is typically explained via the development of colourful and exotic theories and scenarios, which are formed solely in order to support such failure; rather than acknowledge the more commonplace actual cause(s) which lie directly with the operational performance of the service company and the operator themselves. Introduction For far too many years now, in low volume operational regions, one-off, pilot, exploration or appraisal fracturing stimulation operations have failed to measure up to the standards that the service sector claim to achieve or indeed delivered to the operator company expectations. There are a number of reasons for this, but ultimately, the unsuccessful outcome of a project begins with the operator failing to ensure that a "qualified" service company was awarded the work. This initial error is then often exacerbated, by such service companies failing to live up to either the submitted technical proposal or their own internal standards. It is not that either the operator or the service company plan for these unsuccessful outcomes, but rather due the lack of specialized skills (in the regions). During the last decade of rapid expansion and subsequent reduction of personnel within the industry, along with the rate of attrition due to retirement and career progression, has resulted in a severe lack of skilled managerial, engineering and field experienced personnel, on both sides of the equation. Effective QA/QC, Ely (1985), starts from the very beginning of any project, Figure 1, from the initial budgeting approach, through the tender itself, the contract award and inherent contract detail Peters (1998), the pre-job planning, the treatment execution and the post treatment evaluation. This paper attempts to outline some of the very important areas which can be common place to certain failure modes, Dees and Coulter (1986), of one type or another. It will demonstrate, that such failures could just as easily have been averted with care taken during any of the inherent stages associated with a project; e.g. pre-contractual planning, pre-qualification tender audit, creation of a request for pricing (which can include very detailed equipment, personnel & equipment requirements), the technical proposal review, the post technical proposal audit, the commercial agreement, pre-treatment on-site equipment function testing, treatment execution and post treatment review and inventory control. Given due consideration of a number of these aspects, the probability of successful stimulation operation can be substantially increased, Heidt et al. (2003). |
