Headquarters Daily report SEPTEMBER 19, 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 - HEADQUARTERS SEP. 19, 1994 MR Number: H-94-0085 NRR DAILY REPORT ITEM GENERIC COMMUNICATIONS BRANCH/EVENTS ASSESSMENT BRANCH DIVISION OF OPERATING REACTOR SUPPORT OFFICE OF NUCLEAR REACTOR REGULATION Subject: N/A NRC Information Notice 94-66, "Overspeed of Turbine-Driven Pumps Caused by Governor Valve Stem Binding," to be issued September 19, 1994. The NRC is issuing this information notice to alert addressees to recent problems regarding binding of governor valves for turbine-driven pumps that have resulted in overspeed trips. Technical contacts: M. Branch, RII G. Hornseth, NRR (804) 357-2101 (301) 504-2756 S. Tingen, RII F. Grubelich, NRR (804) 357-2101 (301) 504-2784 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I SEPTEMBER 19, 1994 Licensee/Facility: Notification: Boston Edison Co. MR Number: 1-94-0107 Pilgrim 1 Date: 09/19/94 Plymouth,Massachusetts SRI PC Dockets: 50-293 BWR/GE-3 Subject: UPDATE ON GENERATOR PROBLEMS CAUSING 8/29 REACTOR TRIP Reportable Event Number: N/A Discussion: On 8/29, a turbine-generator load reject and automatic reactor trip occurred from 100 percent power (reportable event No. 27720, MR No. 1-94-0097). The turbine-generator lockout was caused by an unexplained ground that caused a neutral bus overvoltage condition. The licensee subsequently disassembled the generator and identified indications of overheating and damage to at least two of the 120 stator bars. The affected bars are connected electrically in series in the same phase and are connected mechanically in series for stator cooling water flow. One of the bars has been shipped to Massachusetts Institute of Technology metallurgical laboratories where destructive testing techniques will be conducted to assist in the causal analysis of the failure. The licensee is inspecting the generator rotor to determine if it incurred any damage during the event. On 9/7, the licensee formally began a planned 30 day mid cycle outage previously scheduled to begin in early October. On 9/15, the licensee announced its intention to conduct a complete generator stator bar replacement in lieu of a partial rewind of damaged or suspect stator bars. Present estimates indicate plant readiness for restart in mid-December. Presently, the licensee is evaluating scheduling options to bring forward work scheduled for the April 1995 refueling outage during this extended outage period. Additionally, the licensee is evaluating the potential to reschedule the refueling outage from the spring to the fall of 1995. The licensee has issued several media releases and conducted an informational briefing regarding this event, and the anticipated scope of outage and repair potentials. Regional Action: The resident inspectors continue to assess the licensee's MDAT investigation of equipment anomalies encountered during the load reject and reactor trip and the conduct of outage activities. Contact: John MacDonald (508)747-0565 Beth Korona (508)747-0565 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II SEPTEMBER 19, 1994 Licensee/Facility: Notification: Tennessee Valley Authority MR Number: 2-94-0080 Watts Bar 1 2 Date: 09/19/94 Spring City,Tennessee Dockets: 50-390,50-391 PWR/W-4-LP,PWR/W-4-LP Subject: WATTS BAR EVACUATION Reportable Event Number: N/A Discussion: On September 17, 1994, at approximately 10:50 a.m., a chemical reaction occurred with excess epoxy grout being utilized to grout the 1A-A Centrifugal Charging Pump pedestal. This reaction generated vapors and smoke resulting in the evacuation of the Auxiliary Building at 11:05 a.m. The Turbine Building and Reactor Building were evacuated as a precaution. The smoke and vapors did cause mild irritation to some exposed personnel. Eight personnel were taken to Rhea County Medical Center as a precaution on a non-emergency basis. The personnel were later released with no physical problems detected. Turbine Building access was allowed at 3:37 p.m., on September 17, and Auxiliary Building access was allowed at 6:18 a.m., on September 18, 1994. The licensee has initiated an Incident Investigation of the event. Preliminary review has disclosed that the specific type of grout utilized develops an exothermic chemical reaction. An excess amount grout was left in a bucket outside the pump room leading to the event. There has been media interest on this matter. The licensee has not issued a press release but made verbal notification to local news media. Regional Action: The resident inspectors are continuing to follow this issue. Contact: Paul Fredrickson (404)331-5649 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV SEPTEMBER 19, 1994 Licensee/Facility: Notification: Wolf Creek Nuclear Oper. Corp. MR Number: 4-94-0099 Wolf Creek 1 Date: 09/16/94 Burlington,Kansas SRI Observation Dockets: 50-482 PWR/W-4-LP Subject: UNIT SHUTDOWN FOR REFUELING OUTAGE Reportable Event Number: N/A Discussion: On September 16, 1994, the licensee shut down the unit to begin the seventh refueling outage. The outage is scheduled to last 57 days. Major activities include high pressure and low pressure Turbine B inspection and refurbishment, 100 percent eddy current testing of Steam Generators A and D, pressure pulse and sludge lance cleaning of all steam generators, replacement of Reactor Coolant Pump C motor, replacement of essential service water containment isolation valves, completion of Generic Letter 89-10 in-plant activities, replacement of the emergency diesel generator exhaust manifolds, elimination of steam generator hydraulic snubbers, and installation of reactor coolant system thermal expansion instrumentation. Regional Action: Resident and Regional inspectors and Regional staff will monitor the unit shutdown and outage activities. Contact: J. F. Ringwald (316)364-8653 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV SEPTEMBER 19, 1994 Licensee/Facility: Notification: Wolf Creek Nuclear Oper. Corp. MR Number: 4-94-0100 Wolf Creek 1 Date: 09/19/94 Burlington,Kansas Licensee to SRI Telecon Dockets: 50-482 PWR/W-4-LP Subject: INADVERTENT PRESSURIZER DRAINDOWN AND PARTIAL DEPRESSURIZATION Reportable Event Number: N/A Discussion: On September 17, 1994, at 4:10 a.m., with the plant in Mode 4 at 350 psig, operators opened a flow path from the reactor coolant system through the residual heat removal RHR system to the refueling water storage tank (RWST). At the time of the event, operators were using RHR Train A for cooldown of the unit. This transferred approximately 10,000 gallons of water and partially depressurized the reactor coolant system. While performing motor-operated valve VOTES testing on Valve EJ HV8716A, the RHR Train A recirculation valve, operators also began lining up the RHR Train B system for recirculation to the RWST. Operators opened Valve BN V8717, the common RHR recirculation valve to the RWST. The next time that the VOTES testing required EJ HV8716A open, a flow path was created from the RCS through these two valves to the RWST through an 8-inch line. This drained the pressurizer from nearly full to nearly empty, depressurized the RCS from 350 psig to approximately 200 psig, transferred approximately 10,000 gallons of water from the RCS to the RWST. The RWST overflowed, transferring approximately 600 gallons of water to the liquid radwaste system. The RCS remained subcooled. Operators terminated the event by closing the Train A valve, stopped the two running reactor coolant pumps, stabilized the plant, and refilled the pressurizer using normal charging. Licensee management stopped cooldown activities and other outage activities which could impact plant operations while evaluating the event. Eight hours later, licensee management permitted all outage activities to continue. Regional Action: The Senior Resident Inspector responded to the control room to evaluate licensee actions. Region IV will continue to monitor licensee outage activities. Contact: J. F. Ringwald (316)364-8653 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION IV SEPTEMBER 19, 1994 Licensee/Facility: Notification: Entergy Operations, Inc. MR Number: 4-94-0101 Waterford 3 Date: 09/19/94 Killona,Louisiana SRI Dockets: 50-382 PWR/CE Subject: BORATION EVENT Reportable Event Number: N/A Discussion: On September 16, 1994, at 4:40 p.m., during a routine boration at Waterford 3, an operator error resulted in the addition of boric acid directly to the reactor coolant system (RCS) instead of to the volume control tank. Within 2 minutes, the operator detected the error and injected pure water into the VCT to compensate for the direct boration. Turbine power was lowered to maintain RCS temperature matched with turbine load and reactor power was stabilized at 98.5 percent power with RCS cold leg temperature at 545 degrees Fahrenheit. The error occurred due to the operator becoming distracted during the boration by a number of control panel annuciators related to ongoing ground testing. As a result, the operator failed to complete all the procedure steps before recommencing the boration to the VCT. Although no Technical Specification limits were exceeded, this is the fourth example of a boration/dilution error in the last 4 weeks at Waterford. The licensee is currently evaluating the incident and has implemented an event review team, including interviews with all the operators. Regional Action: The resident inspectors will continue to follow up. Region IV has recently completed a Special Inspection of recent dilution events at Waterford 3 and is evaluating whether enforcement action is warranted. In addition, the licensee's operational performace related to reactivity control is one topic to be discussed in a management meeting scheduled for September 22, 1994. Contact: C. A. VanDenburgh (817)860-8161