Headquarters Daily Report JULY 21, 1997 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS û REGION I û REGION II û REGION III û REGION IV û PRIORITY ATTENTION REQUIRED MORNING REPORT - HEADQUARTERS JULY 21, 1997 MR Number: H-97-0088 NRR DAILY REPORT ITEM GENERIC COMMUNICATIONS Generic Letter 97-03, "ANNUAL FINANCIAL SURETY UPDATE REQUIREMENTS FOR URANIUM RECOVERY LICENSEES," was issued on July 9, 1997. This letter was issued to uranium recovery licensees and State officials to notify them of certain procedural requirements for surety submittals. The letter documents information provided by NRC staff during the November 1996 meeting with the uranium recovery industry to clarify general requirements for surety submittals. Contact: Daniel M. Gillen, NMSS 301-415-7295 E-mail: dmg2@nrc.gov _ REGION II MORNING REPORT PAGE 2 JULY 21, 1997 Licensee/Facility: Notification: Duke Power Co. MR Number: 2-97-0055 Mc Guire 2 Date: 07/21/97 Cornelius,North Carolina Dockets: 50-370 PWR/W-4-LP Subject: ICE CONDENSER DOORS EXCEED OPENING FORCE LIMIT - UPDATE Reportable Event Number: 32646 Discussion: On July 18, with McGuire Unit 2 in cold shutdown (Mode 5), the opening force on ten lower ice condenser doors in eight of the 24 bays (two doors per bay) was found to exceed the Technical Specification (TS) limit. Investigation revealed that the affected doors were dragging on flashing between the floor and the bottom of the doors. This problem has been attributed to upward movement in the floor, where the floor (wear slab) appeared to be raised by approximately 0.5 to 0.75 inches above its normal height. Moisture increases in the flooring concrete coupled with freeze/thaw cycles of the water are the likely phenomena causing this problem. The licensee has identified several operational events and other periods of possible degraded cooling equipment performance that may have contributed to the problem. To correct a problem, all 48 lower ice condenser doors in Unit 2 have been modified by removing a portion of the flashing (including the small amount of insulation it protected) that interfered with the doors. This has left a minimum clearance of at least 2.25 inches between the floor and the remaining flashing. Based on operational data from the Sequoyah Nuclear Power Plant where a similar, but more severe concrete heave occurred, this modification should provide a sufficient gap under a worst case floor movement for the remainder of the operating cycle. The licensee has determined that sufficient ice mass exists to handle the increased sublimation rates for the remaining two months in the Unit 2 fuel cycle. On McGuire Unit 1, the associated TS 18-month "door opening force" surveillance was satisfactorily performed approximately three months ago. To further verify Unit 1 lower ice condenser door operability, several of the Unit 1 doors were examined by use of a video camera that was lowered from the intermediate doors to the wear slab. Video surveillance did not reveal deformation of flashing or evidence of concrete heave. Regional Action: The resident inspectors observed the licensee's corrective actions and continue to follow the licensee's recovery actions. Region II and the resident inspectors at Catawba are currently following the licensee's assessment of the applicability of the problem at Catawba. Contact: ROBERT CARROLL (404)562-4511 _ REGION IV MORNING REPORT PAGE 3 JULY 21, 1997 Licensee/Facility: Notification: Union Electric Co. MR Number: 4-97-0058 Callaway 1 Date: 07/19/97 Fulton,Missouri SRI via telephone Dockets: 50-483 PWR/W-4-LP Subject: LOSS OF ANNUNCIATORS (refer to Event 32653) Discussion: On July 19, 1997, at 4 p.m. (CDT) a lightning strike at the water treatment plant at the Callaway Plant resulted in plant annunciator problems. Numerous control board annunciators were received and the plant operators entered the abnormal procedure for loss of control room alarms. During subsequent troubleshooting, the licensee identified that the annunciator power supplies had degraded output voltage (approximately 25 VDC, normal 120-130 VDC). The degraded voltage was determined to be the result of several (4) connector cards in one of the annunciator cabinets shorting as a result of the lighting strike and loading down the power supplies. Voltage returned to normal when the shorted connector cards were deenergized at about 4:30 p.m. This restored approximately 90 percent of the annunciators. After further review, the licensee determined that the functionality of the annunciators was not assured between the time of the lightning strike and deenergization of the shorted connector cards (approximately 25 minutes) and, therefore, decided to make the appropriate notifications that conditions had been met to declare a Notification of Unusual Event during that period. The annunciators supplied through the shorted connector cards remained out of service until approximately 3:48 a.m. on July 20, when the shorted connector cards were repaired and replaced. An Event Review Team was formed by the licensee and is continuing to investigate the event. Regional Action: The Senior Resident Inspector responded to the site and will continue to monitor the licensee's actions. Contact: D. Passehl (573)676-3181 _