7 octobre 2013
Découverte de résidus blancs autour d’une pénétration de fond de cuve lors d’une inspection planifiée. Cette indication de fuite n’a pas été identifiée sur d’autres pénétrations. L’analyse des résidus blancs est en cours, comme si l’hypothèse d’un autre produit que du bore était possible...
Type : PWR - P : 3 867 MWTh - Première divergence : 10 1987
Available in english only.
Event Number : 49416 Facility : PALO VERDE - State : AZ - Unit : [3] RX Type : [3] CE -
Event Date : 10/07/2013 - Event Time : 02:19
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(3)(ii)(A) - DEGRADED CONDITION
Initial PWR : 0 % Current PWR : 0 %
Event Text
POTENTIAL REACTOR COOLANT SYSTEM PRESSURE BOUNDARY LEAKAGE IDENTIFIED
"The following event description is based on information currently available. If through subsequent reviews of this event additional information is identified that is pertinent to this event or alters the information being provided at this time a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73.
"At approximately 2100 MST on 10/06/13, while performing planned routine visual examinations of the Unit 3 reactor vessel bottom mounted instrumentation (BMI) nozzles, a white residue was identified around the annulus region of BMI penetration number 3. The BMI visual examinations are performed using remote video and photographic equipment to meet the in-service inspection requirements of 10 CFR 50.55a(g)(6)(ii)(E) and ASME Code Case N-722-1. At this time, no other indications of leakage have been identified and inspections of the remaining BMI penetrations are ongoing.
"Following review of the photographic images by qualified engineering personnel, at 0219 [MST] on 10/07/13, it was determined, based on past and present photographic evidence, the white residue is most likely dry boric acid resulting from reactor coolant system pressure boundary leakage. An activity to sample and analyze the white residue is being planned and will be performed as soon as possible. This notification is being made for a degraded condition pursuant to the requirements of 10 CFR 50.72(b)(3)(ii)(A).
"The NRC Resident Inspectors have been informed of this condition."
Source : https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2013/20131008en.html