29 janvier 2014
Lors d’inspections sur les mécanismes supérieurs de commande des grappes de contrôle de la réaction en chaîne, 17 mécanismes sur les 45 inspectés ne respectaient pas les critères réglementaires. Aucun signe de fuite n’a été décelé. Les réparations et contrôles sont en cours d’exécution : le document n’évoque pas l’irradiation massive des travailleurs exécutant ces tâches.
Type : PWR - Puissance thermique : 2 565 MWTh - Première divergence : 05/71 (soit 42 ans)
Available in english only.
Event Number : 49773 - Facility : PALISADES - State : MI Unit : [1] - RX Type : [1] CE -
Event Date : 01/29/2014 — Event Time : 09:00
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(3)(ii)(A) - DEGRADED CONDITION
Initial PWR : 0 % Current PWR : 0 %
Event Text
INDICATIONS IDENTIFIED ON CONTROL ROD DRIVE MECHANISM HOUSINGS
"On January 29, 2014, during planned inspections of control rod drive mechanism (CRDM) upper housings, it was determined that the inspection results for some housings did not meet the applicable acceptance criteria. That is, evaluations of the housing indications are being performed under ASME Code, Section XI, IWB-3600, ’Analytical Evaluation of Flaws,’ and indications were identified that exceed acceptance criteria specified in the Code. None of the indications were through-wall and there was no evidence of leakage.
"The housing indications, varying in depth and length characteristics, were identified in 17 of the 45 CRDM housings inspected. All 45 CRDM housings were inspected, which constituted 100% extent of condition inspection.
"The plant was in cold shutdown at 0% power for a planned refueling outage at the time of discovery. Replacement or repair actions are in progress and will be completed prior to plant startup from the outage.
"This condition has no impact to the health and safety of the public.
"This report is being made in accordance with 10CFR 50.72(b)(3)(ii)(A), since indications were found that did not meet acceptance criteria referenced in ASME Code, Section XI.
"The licensee notified the NRC Senior Resident Inspector."
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2014/20140130en.html