Addressing the Challenge of Inspecting Buried Nuclear Piping in Nuclear Power Plants

Similar to many other industries, nuclear power plants (NPPs) have many kilometres of buried pipe that is not readily accessible for direct inspection. Given the nature of the systems, the nuclear industry experiences additional challenges as many services run in the same area, leading to what is described as a “spaghetti bowl” of piping. As a result, the traditional indirect, over the line, inspection practices developed for the oil and gas industry have not always been successfully applied at nuclear power plants. To address this issue, a collaborative Electric Power Research Institute/CANDU Owners Group (EPRI/COG) research project was established with Mears Group Inc. and Atomic Energy of Canada Limited (AECL) Nuclear Laboratories. In this program, initial testing of four methods was carried out at the Mears Group Inc, test site that had been modified with additional grounding systems to simulate a nuclear power plant. This was followed by testing of the same methods at the AECL Nuclear Laboratories Chalk River site. This paper will discuss the results of those studies and present some of the findings that were made that can help to overcome the challenges faced by Nuclear Power Plants.