This paper describes a framework for assessing environmental risks associated with E&P operations, based on the sequential application of:
codes of practice and standards;
qualitative probability and consequence analysis;
quantitative risk assessment.
This paper discusses approaches for managing the environmental risks associated with offshore E&P operations. The emphasis is on developing a systematic framework for managing environmental risks which makes best use of existing tools, techniques and procedures.
Our use of the term "risk" follows the definition developed by the Royal Society Study Group on Risk as "…the probability that a particular adverse event occurs during a stated period of time, or results from a particular challenge." This definition focuses on the quantitative elements of probability and consequence, emphasising the role of science in risk management. However, "environmental risk" means different things to different people. To the layman, an activity is often perceived as "risky" based solely on its potential consequences, irrespective of the likelihood of its occurrence. Conversely, safety professionals familiar with the use of Quantitative Risk Assessment (QRA) might equate "environmental risk assessment" with a similarly detailed, exhaustive, and quantified approach.
We believe that such views reflect only small elements of the environmental risk management process, and that a range of existing tools and techniques can be drawn together within a coherent and robust framework for managing environmental risks.
Our guiding principles are that:
approaches must have a proven, practical value;
methods used must be simple and readily understandable;
the process must inspire regulatory and public confidence.
Environmental risk management comprises five basic steps:
Describe the intended activity.
Identity hazards and effects associated with the activity and characterise the environment.
Evaluate the magnitude and significance of hazards and effects and identity and assess risk reduction measures.
Implement control techniques to manage hazards and eliminate or minimise the severity of effects.
Develop plans and procedures for managing the consequences of exceptional events.
Although presented sequentially, the stages in this process are not always distinct in practice, with overlaps and necessary feedback from one stage to another. There is nothing novel in this approach - it forms the basis of the Environmental Assessment (EA) process. It should also be noted that the most effective way to manage risks is to eliminate the underlying hazard. For example, waste reduction at source underpins the hierarchy of choices for sound waste management.
Assessing the significance of hazards and effects - Step 3 - is the key to this process, and it is here that the concept of risk becomes important. This may require external consultation to ensure all relevant information is included, and that social and political factors are identified.
In describing the significance of environmental risk it is useful to draw parallels with the underlying principle of safety management that risks should be managed to be As Low As Reasonably Practicable (ALARP). Associated with this is the notion of Tolerability of Risk (ToR), which is based on the premise that risks can be allocated to one of the following categories:
risks are sufficiently high to be intolerable;
risks are tolerable, but managed actively to be ALARP, and only undertaken when specific benefits are required;
risks are sufficiently low to be acceptable, with no action required to reduce further.