Headquarters Daily report Headquarters Daily report DECEMBER 05, 1994 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS X REGION I X REGION II X REGION III X REGION IV X *************************************************************************** PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I DECEMBER 5, 1994 Licensee/Facility: Notification: Pennsylvania Power & Light Co. MR Number: 1-94-0130 Susquehanna 1 Date: 12/05/94 Allentown,Pennsylvania SRI PC Dockets: 50-387 BWR/GE-4 Subject: Susquehanna Unit 1 Feedwater Transient Reportable Event Number: N/A Discussion: On 11/30/94 the Unit 1 control room received a 125V DC battery trouble alarm. Unit 2 had been receiving this alarm recently, which the operators responded to by placing the battery charger in "equalize" mode. Following the Unit 2 practice, Unit 1 operators placed the 125V DC battery in equalize. While in "equalize" mode, the battery terminals are placed at a voltage slightly higher than normal float voltage thereby equalizing the battery cell voltages to the manufacturer's recommended value. Shortly thereafter, at 2031, the reactor water level high alarm came in. The control room operators noticed that the reactor water level and power had increased, `B' reactor feed flow and `C' narrow range level instruments failed down scale together with some other instruments, computer points and recording that also failed. Due to the loss of the `B' reactor feed flow signal, the reactor water level control system (actual feed flow did not decrease), responded by increasing feed flow and stabilized reactor level to 49 inches. The control room operators entered the offnormal procedure, and placed the reactor water level control system in single element control. The level was reduced to the normal value of 35 inches. The licensee is currently evaluating the cause of the event, but suspects that a Zener diode in the feedwater control circuit failed when the battery charger was transferred to equalize, blowing several fuses and resulting in the instrument losses. The exact cause of the failure is not known yet. Licensee suspects that the Zener diode could have been undersized for its application. The cause of the battery trouble alarm was a setpoint drift of the battery monitor, and not a battery problem. The licensee's calculated reactor power increased during the transient to 104% for approximately 21 seconds. The licensee conservatively reduced power to 98% until all the heat balance inputs were verified. Currently the reactor water level control system is back in three element control, and the unit is operating at 100% power level. The licensee made a 24 hour notification to the NRC as required by license conditions for exceeding licensed thermal power. Regional Action: The resident inspector will continue to follow up on the licensee's investigation and corrective measures. NRR has been informed. Contact: John White (610)337-5114 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I DECEMBER 5, 1994 Licensee/Facility: Notification: Rti, Inc. MR Number: 1-94-0131 South Jersey Process Technology,Inc Date: 12/05/94 Rockaway,New Jersey Dockets: 03022307 License No: 29-20900-01 Subject: Commercial Irradiator Cobalt-60 Sources Stuck Above Pool Shield Reportable Event Number: N/A Discussion: On December 2, 1994, at 3:00 p.m., the licensee's Radiation Safety Officer (RSO) notified the NRC Region I staff that source racks containing licensed byproduct material possessed at the licensee's commercial pool-type irradiator facility, Salem, New Jersey, had become stuck in the unshielded position. This occurred at 2:05 p.m., but by manually adjusting the conveyor system motor from outside of the shielded irradiator room, the source rack was freed from the source shroud and the byproduct material descended into the pool and was fully shielded by 2:45 p.m. The RSO stated that they would not resume operations until the cause of the stuck sources is investigated and corrective actions are taken to prevent recurrence. Because of NRC concern that operations might be resumed without a full understanding of the causes involved and implementation of necessary corrective actions, a Confirmatory Action Letter (CAL) was negotiated with the licensee and issued on December 2, 1994. The CAL requires the licensee to: 1. Remain shut down until NRC authorizes resumption of operations. 2. Investigate causes and take corrective actions prior to startup 3. Obtain verbal approval from NRC before resuming irradiator operation. 4. Provide a written report to NRC Region I Regional Administrator providing an evaluation of the problem(s) and all actions taken or planned to prevent a similar incident in the future. Regional Action: The NRC remained in contact with the licensee over the weekend to follow the actions taken by the licensee to correct the problem and will continue to follow-up on corrective measures as long as is necessary. Contact: Anthony S. Kirkwood (610)337-5050 Walter J. Pasciak (610)337-5258 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II DECEMBER 5, 1994 Licensee/Facility: Notification: Duke Power Co. MR Number: 2-94-0105 Catawba 1 2 Date: 12/05/94 York,South Carolina Dockets: 50-413,50-414 PWR/W-4-LP,PWR/W-4-LP Subject: SECURITY MANAGEMENT CHANGE Reportable Event Number: N/A Discussion: The licensee recently annouced that the Site Security Manager, J. Roach was assuming the Safety Manager position. Effective December 1, 1994, T. Byers was selected to become the Security Manager for the Catawba Site. Contact: R. FREUDENBERGER (803)831-2963 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION III DECEMBER 5, 1994 Licensee/Facility: Notification: Commonwealth Edison Co. MR Number: 3-94-0229 Byron 1 Date: 12/05/94 Byron,Illinois E-MAIL Dockets: 50-454 PWR/W-4-LP Subject: UNIT 1 SHUTDOWN EXCESS OF 48 HOURS DUE TO CONDENSER TUBE LEAK Reportable Event Number: N/A Discussion: On December 3, 1994 at approximately 8:30 p.m. (CST), the Unit 1 condensate system experienced a significant chemistry excursion. The licensee initially responded to high alarms in the secondary system in-line chemistry monitors. Subsequently, chemistry samples were taken to analyze and confirm the secondary water quality. The initial results indicated a conductivity of 210 umhos/cm and sodium concentration of 2500 ppb. The licensee commenced a power reduction, and proceeded to shutdown the plant due to the severity of the secondary water chemistry excursion. At approximately 1:30 a.m. (CST) on December 4, 1994, Unit 1 was shutdown. As of 7:00 a.m. (CST), December 5, 1994, Unit 1 secondary chemistry was: sodium 3900 ppb, chloride 10200 ppb, sulfate 55000 ppb, and conductivity of 488 umhos/cm. These concentrations are comparable to those found in the river water which Byron uses for the circulating water system. Normal secondary chemical concentrations are: sodium <.5 ppb, chloride .3 ppb, sulfate 4 ppb, and conductivity .5 umhos/cm. On December 5, 1994, Unit 1 is in Mode 4 at approximately 210 degrees F. The licensee has narrowed the cause of the secondary chemistry event to be a circulating water leak in the condenser circulating water box. The licensee has not yet been able to quantify the extent of the damage to the water box. The length of the forced outage will be determined once the final cause and repairs have been determined. Regional Action: The senior resident inspector observed the licensee's shutdown activities. The inspectors are following the licensee's corrective actions. Contact: L.F. MILLER (708)829-9629 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV DECEMBER 5, 1994 Licensee/Facility: Notification: Entergy Operations, Inc. MR Number: 4-94-0139 River Bend 1 Date: 12/05/94 St Francisville,Louisiana Senior Resident Inspector Dockets: 50-458 BWR/GE-6 Subject: AUTOMATIC REACTOR SCRAM Reportable Event Number: 28106 Discussion: On December 4, 1994, while the plant was operating at 100 percent power, the main steam isolation valves (MSIVs) closed resulting in a reactor trip. Post-trip response was as expected and all safety-related systems responded as designed and the operators stabilized the plant in Hot Shutdown (Mode 3). The MSIVs closed as a result of a human error during the performance of the containment and drywell manual isolation actuation monthly channel functional surveillance test. Due to a miscommunication during the test, the maintenance technician signed the step to reset the Channel A trip signal as completed without verifying that the operator actually performed the step. The technician then directed the operator to place Channel B in the tripped condition causing the MSIVs to close. After the reactor trip, maintenance personnel performed a walkdown of the drywell to determine the cause of unidentified reactor coolant system (RCS) leakage that had been slowly increasing to 1.72 gpm since the plant startup on November 3, 1994. (This leakage had dropped to 0.6 gpm immediately after the reactor trip.) During the walkdown, maintenance personnel located a hairline crack in control rod drive (CRD) 32-17 insert piping and excessive condensation in drywell unit Cooler 1E. The CRD piping crack was weeping approximately 20 drops per minute and had a brown substance, similar to the foreign material previously found on October 10, 1994, on the CRD piping. (Morning Reports 4-94-019 and 4-94-020 described the identification of previous CRD through-wall cracking due to this foreign material contamination.) The licensee's previous investigation determined that the brown substance was an adhesive used to install anti-sweat insulation on service water piping during original construction. Although the licensee had performed a 100 percent walkdown of the CRD piping after the first event, this further contamination was apparently overlooked. Nevertheless, the licensee currently believes that the weeping CRD pipe was not the source of the unidentified leakage and plans further drywell inspections, including hydrostatic testing, to determine the source of unidentified RCS leakage. The licensee believes the excessive condensation in the drywell cooler may be due to a steam leak and plans further evaluation. The licensee is evaluating the root causes and corrective actions for the human error associated with the reactor trip, the failure to locate the brown substance on the CRD piping during past inspections, and the source of unidentified RCS leakage. In addition, the licensee is preparing to repair the battery charger, which exhibited minor voltage oscillations during recent an equalizing charge. Regional Action: The resident inspector responded to the site following the reactor trip. The resident inspectors will continue to followup on the CRD system leakage and corrective actions. Contact: C. A. VanDenburgh (817)860-8161 DECEMBER 06, 1994 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS X REGION I X REGION II X REGION III X REGION IV X *************************************************************************** PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV DECEMBER 6, 1994 Licensee/Facility: Notification: Southern California Edison & San MR Number: 4-94-0140 Diego Gas & Electric Co. Date: 12/06/94 San Onofre 3 Resident Inspectors San Clemente,California Dockets: 50-362 PWR/CE Subject: WETTED EMERGENCY DIESEL GENERATOR ELECTRICAL CONNECTIONS Reportable Event Number: N/A Discussion: On November 30, 1994, during unrelated routine maintenance, with both Units at full power, the licensee found water intrusion in a Unit 3 emergency diesel generator (EDG 3G002) cabinet that housed terminal connections for 4.16 KV power lines as they exited the generator and entered underground conduits. The conduits ran to an underground vault covered by a manway. The water was approximately one inch deep at the bottom of the cabinet, had formed drops on the inside top of the panel, and had wetted the wiring insulation and connection points, creating a risk of electrical flashover between phases. The licensee dried and cleaned the cabinet and megger checked the associated bussing and cables. The megger checks were satisfactory. There was no evidence of water intrusion from the top of the cabinet. The licensee and the resident inspector subsequently inspected the underground vault (not designed to be water tight) and found a few inches of water in the vault sump, significantly below the level of the cable trays. The vault contained a water level alarm, which was tested to be operable at a level below the level of the cables in the vault. The licensee and the resident inspector visually inspected the equivalent cabinet for the other three emergency diesel generators on site and found no evidence of standing water or moisture induced degradation. The licensee considered that, since the wire routing from the cabinet to the underground vault provided for air passage between the two areas, the moisture found at EDG 3G002 was due to humid air from the vault condensing in the cabinet. The licensee sealed the gap between the cables and the conduit at the base of the EDG 3G002 cabinet in order to mitigate the passage of moisture-laden air. The licensee plans to seal cabinets in the other EDGs at the next available opportunity. Regional Action: The resident and project inspectors followed the licensee corrective actions and inspected the wetted panel and vault. Contact: H. Wong (510)975-0296 J. Russell (714)492-2461