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ITEM B-49: INSERVICE INSPECTION CRITERIA AND CORROSION PREVENTION CRITERIA FOR CONTAINMENTSDESCRIPTIONGDC-53, "Provisions for Containment Testing and Inspection," requires in part that the reactor containment be designed to permit (1) periodic inspection of all important areas and (2) an appropriate surveillance program. 10 CFR 50, Appendix J, "Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors," requires a general inspection of the surfaces of the containment before any Type A test to uncover any evidence of structural deterioration. Containment designs typically use any one of the following structural materials: steel, steel-lined reinforced concrete, and steel-lined prestressed concrete. To date, the only detailed criteria that have been developed for ISI of containments relate to tendon surveillance for prestressed concrete containments. These criteria are contained in Regulatory Guides 1.35481 and 1.90482 which address ungrouted and grouted tendons, respectively. These Regulatory Guides deal primarily with the prestressing hardware; no detailed ISI criteria exist for the steel liner or other portions of the containment. Similarly, there are no criteria for ISI of steel containments or steel-lined reinforced concrete containments. In view of this, detailed and comprehensive criteria need to be developed for performing ISI of all types of containments. In addition, the long-term corrosion problems of reinforcements and of the steel liner in contact with concrete in concrete containments, or the corrosion of the steel surface in contact with the water in BWR suppression chambers, have yet to be adequately analyzed. Long-term studies of these corrosion phenomena need to be undertaken to develop criteria and requirements to prevent corrosion in all types of containments. This issue is documented in NUREG-0471.3 CONCLUSIONThis item is a Licensing Issue.
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