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 Start dateReporting criterionTitleEvent descriptionSystemLER
ENS 4067816 April 2004 05:00:0010 CFR 21.21Part 21 Notification Due to Potential Cracking in B4C Hydrid Control RodsThis issue concerns the potential for cracking in the tips of the Westinghouse designed B4C Hybrid Rod Cluster Control Assembly (RCCA) while in operation. Westinghouse supplied B4C Hybrid RCCAs are currently in use in the U.S. only at Tennessee Valley Authority's (TVA) Watts Bar Nuclear Plant. Cracks in the hybrid RCCAs could result in a potential loss of B4C (a neutron absorber) from the RCCA if left uncorrected. Westinghouse will review and revise its guidelines on the use and expected life of B4C Hybrid RCCAs to assure that this information is accurately reflected and communicated to its customers.Control Rod