Implementing a Quantitative Geohazard Frequency Analysis Framework as a Component of Risk Assessment of New Pipelines

Abstract

In the last 5 years in Canada, regulators have been requesting that new pipeline projects provide quantitative risk management of all credible geohazards involving the proposed pipeline corridor so it can be demonstrated that geohazards are being recognized prioritized and that adequate resources are being allocated and to minimize the impact of adverse consequences of pipeline construction and operation. Complete risk management includes risk analysis that identifies credible geohazards sites, estimates their annual frequency or probability of pipeline failure and, when combined with a consequence of pipeline failure, estimates the risk from each hazard. This paper presents a framework and methodology that quantitatively estimates the Frequency of Loss of Containment (FLoC) for several types of geohazards that meet the requirements for geohazard identification and frequency analysis components of risk analysis. This framework builds on an international geohazard management framework advanced in the last decade by the Australian Geomechanics Society, British Columbia forestry industry, used in geohazard management programs for operating pipelines and proposed pipeline projects in Canada. The framework provides a repeatable and defensible methodology that is intended to be scalable to accept inputs from feasibility level desktop studies, through field-based observations, and incorporate proposed mitigations. This updated framework was most recently implemented on a proposed large diameter transmission pipeline route crossing the varied terrains of Western Canada, the results of which have been adjusted for Owner confidentiality, but are presented to demonstrate the application of the methodology and the effectiveness of communicating the overall hazard frequency reduction as a result of applying site specific mitigations.

Mitigation of Risks Associated with Gas Pipeline Failure by Using Quantitative Risk Management Approach: A Descriptive Study on Gas Industry

“…To assess the probability throughout the project life cycle, frequency analyses of the risks highlighted concerning the proposed project have been done. Risk frequencies were assessed based on the study of historical accident frequency data and professionally evaluated in respect to the proposed project [29]. The following frequency categories and criteria were created based on the range of possibilities for distinct possible dangers during pipeline operations related to the proposed project (Table 1).…”