Basis for the Expectation of a Near Term Increase in the Number of Reports of Degraded Buried Piping

Current inspection requirements for buried piping are based on the objectives of ensuring that the safety function of the piping is maintained and ensuring that the radiation exposure to plant employees and the general public remains below regulatory limits. Current inspection procedures have been fully effective in accomplishing these objectives. Despite this success, both the industry and the NRC recognize that an increase in both the sensitivity and number of inspections is desirable. To that end the NRC is developing a new Aging Management Program for buried piping which will be used in the license renewal process and the nuclear industry has developed a buried piping initiative. Each of these programs will result in more inspections which have a higher probability of detecting degraded piping than is currently the case. While these additional inspections will result in improved reliability of buried piping, in the short term the NRC anticipates that they will result in an increase in the number of reports of degraded piping.

Increased inspection can be expected to result in increased detection. Following the implementation of the industry Buried Piping Initiative and the Buried Piping Aging Management Program, unless there is specific information to the contrary, the NRC will view an increase in the number of reports of degraded buried piping as a natural consequence of additional inspections and not a cause for additional concern.