Event Notification Report for May 06, 2004

REACTOR VESSEL HEAD NOZZLE WELD AREA FLAW

"During performance of NDE examinations of the Point Beach Nuclear Plant (PBNP) Unit 1 reactor pressure vessel (RPV) head required by the First Revised NRC Order (EA-03-009), flaw indications were identified on Nozzle 26. The ultrasonic examination (UT) signal for nozzle 26 identified flaw indications in the J-groove weld area that extend into the CRDM tube base material.

"A dye-penetrant (PT) examination of the nozzle 26 CRDM J-groove material was also performed. The PT exams showed minor surface indications that required further evaluation. Following minor excavation of the weld surface, additional examinations of the J-groove surface were performed. The results of these exams indicated the existence of flaws in the weld that do not meet accepted flaw evaluation guidance.

"Based upon preliminary analysis, it is expected that these indications would not be found acceptable under ASME standards. Therefore, this condition represents degradation of a principal safety barrier reportable under 10 CFR 50.72(b)(3)(ii)(A).

"PBNP Unit 1 Nozzle 26 is planned to be repaired prior to placing the RPV Head back into service.

"The condition was determined to be reportable at 1046 CDT on May 6, 2004. The licensee has notified the Resident Inspectors."

LOSS OF FOUR TRITIUM EXIT SIGNS

The following information was obtained from the Master Materials License Holder via facsimile:

"The loss occurred at a medical permittee authorized under the master materials license issued to the Department of Veterans Affairs, NRC License 03-23853 01 VA. The permittee is the Clement T. Zablocki VA Medical Center, Milwaukee, Wisconsin.

"The loss occurred circa 2001 and was discovered on May 6, 2004. The basis for the report is under 10 CFR 31.5(c)(10) in that radioactive materials obtained under a general license were lost and the reporting requirements in 10 CFR 20.2201 must be followed.

"Specifically, the permittee stated four tritium exit signs were apparently disposed or discarded during a facility construction project circa 2001. The signs were last seen in 2000.

"The signs were either of two models. 'The first model is a 11.5 Curie sign from Shield Source Incorporated. The second model is a 20 Curie sign from SRB Technology. The signs were manufactured circa 1994.

"The Department of Veterans Affairs will evaluate the circumstances related to the loss of radioactive materials and submit a written report to NRC, Region III, within 30 days."

AUTOMATIC REACTOR TRIP AND ACTUATION OF AUXILIARY FEEDWATER SYSTEM

The following information was received from the licensee via facsimile:

"On May 6, 2004, with the reactor at 100 percent power in MODE 1, an unplanned actuation of the reactor protection system occurred. At 1252 [EDT] the reactor was automatically tripped from a power range negative flux rate trip signal. The auxiliary feedwater system actuated as expected to stabilize steam generator levels. All systems functioned as required and no other safety systems were actuated. All control rods inserted on the reactor trip. The operations staff responded to the event in accordance with applicable plant procedures. The plant stabilized at normal operating no-load reactor coolant system temperature and pressure following the reactor trip. Steam generator water levels are being maintained using normal main feedwater. All emergency core cooling system equipment is available. The plant electrical system is available and in a normal configuration. The cause of the plant trip is under investigation.

"This condition is being reported as an unplanned reactor protection system actuation and specified system actuation in accordance with 10 CFR 50.72(b)(2)(iv)(B) and10 CFR 50.72(b)(3)(iv)(A) ."

During the transient, a steam generator power-operated relief valve lifted momentarily and then re-seated. No reportable radiological release occurred during the event.

The licensee notified the NRC Resident Inspector.