Nuclear utilities have many kilometres of piping buried in a relatively small physical area resulting in what has been called a “spaghetti bowl”. Until recently, much of this piping has been neglected and considered “out of sight / out of mind” therefore given a low operational impact. However, current failures have raised the profile of buried piping maintenance with both utilities and regulators.
Buried piping programs face many of the challenges familiar to well run maintenance programs, but these challenges are compounded for a number of reasons. This paper will discuss how Atomic Energy of Canada Limited (AECL) Nuclear Laboratories have partnered with utilities, service providers, CANDU Owners Group (COG), and the Electric Power Research Institute (EPRI) to provide support to the development and implementation of maintenance programs for buried piping.
Initially, AECL developed station strategy manuals to establish a mechanism to ensure a proficient ongoing program. As part of this program, extensive data on the systems was collected using station records. This data was then used to produce risk informed assessments, with the help of EPRI’s BPWORKS™ software, and ultimately the selection of inspection locations. Lessons learned from this work have not only been integrated into the station’s buried piping program, but also incorporated into improvements to the EPRI BPWORKS software.
