Decision analysis is presented as a tool for carrying out a thorough and logical evaluation of alternative strategies to systematically determine the best available produced water management strategy, both economically and environmentally by the application of environmental accounting.
The use of decision analysis is presented as the framework for conducting integrated produced water management studies. The integration of reservoir engineering, environmental regulations, environmental impact assessment, geochemistry, geological studies, process design, risk analysis, QC and financial appraisals with the aim of optimising scale control will be addressed.
The value of decision analysis is not only in helping to structure information and thinking, but also in providing a vehicle for communication between different groups and technical disciplines. A complex decision problem is decomposed into separate components, often in the form of a decision tree, on which perceptions of options, uncertainties and values can be explicitly represented.
The evaluation of options for produced water management will be used as a case study illustrating the stages of the decision analysis process, which are:
Structuring and decomposition of the problem including the evaluation of the options for produced water disposal such as re-injection or surface disposal dependent on environmental regulations
Assessing the payoff of the possible outcomes
Assessing risks and uncertainties such as injectivity impairment, aquifer pollution, process upsets, regulation changes etc
Spreadsheet construction of decision trees
Sensitivity analysis and assessing the value of additional information to help finalize the decision