Effective management of buried piping begins with an understanding of the current condition through a progressive series of steps starting with cataloging known data about the design, service and operational history, through risk ranking and into prioritized inspections to establish a reasonable assurance of the current continued safe operating condition. For a truly effective long term aging management program, a successful buried pipe program must anticipate future degradation rates and establish a frequency for reinspection combined with appropriate corrosion control measures. In some systems, the cost of monitoring together with reinspection can become significant when projected another 20 to 40 years in time. Therefore, it can be more cost effective to perform a life cycle assessment of critical buried piping systems, and benchmark those model predications on the results from the first round of inspections. Where active corrosion is confirmed and the predicted system End of Life is less than the required service life, a preliminary technical review of remediation options is warranted. A technical remediation study feasibility assessment will provide the buried pipe program owner and management with information needed to estimate realistic cash flow projections associated with the impact of leaks and maintenance costs against remediation (i.e., mitigation and replacement) options to maximize the reliability and cost viability of the plant.
This paper outlines a comprehensive approach to evaluating the effectiveness of buried piping using a rigorous approach analyze the impact of degradation and the benefit of remediation option evaluations for degradation control versus simple in-kind pipe replacement. The process considers technical corrosion engineering assessments, engineering evaluations, inspections and mitigation/replacement approaches. Including materials and construction estimates completes the process, yielding a meaningful package from which to begin making well-informed, long-term planning decisions.