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Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO LER)
MONTHYEARNPL-98-0880, Special Rept:On 980913,fire Alarm Control Panels Inoperable for More That Fourteen Days.Troubleshooting of D-401 Panel Following Installation of Replacement Batteries Revealed No Apparent Cause for Spurious Alarms.Panel D-401 Restored1998-10-21021 October 1998 Special Rept:On 980913,fire Alarm Control Panels Inoperable for More That Fourteen Days.Troubleshooting of D-401 Panel Following Installation of Replacement Batteries Revealed No Apparent Cause for Spurious Alarms.Panel D-401 Restored NPL-98-0209, Special Rept Re Fire Barrier Inoperable for Greater than Seven Days.Compensatory Measures Implemented in Accordance W/Fire Protection Program Requirements During Time That Barriers Were Inoperable1998-03-30030 March 1998 Special Rept Re Fire Barrier Inoperable for Greater than Seven Days.Compensatory Measures Implemented in Accordance W/Fire Protection Program Requirements During Time That Barriers Were Inoperable NPL-97-0831, Special Rept:On 971201,fire Protection Wrap Required for Svc Water Pump Motor Cables Had Been Rendered Inoperable for More than Seven Days.Caused by Planned Repair activity.Once- per-hour Fire Patrol Established1997-12-23023 December 1997 Special Rept:On 971201,fire Protection Wrap Required for Svc Water Pump Motor Cables Had Been Rendered Inoperable for More than Seven Days.Caused by Planned Repair activity.Once- per-hour Fire Patrol Established NPL-97-0751, Special Rept:On 971023,low Temp Overpressure Protection Sys Operation Occurred.Caused by Starting Reactor Coolant Pump w/water-solid Reactor Coolant Sys.Operating Personnel Will Be Briefed on Event1997-11-21021 November 1997 Special Rept:On 971023,low Temp Overpressure Protection Sys Operation Occurred.Caused by Starting Reactor Coolant Pump w/water-solid Reactor Coolant Sys.Operating Personnel Will Be Briefed on Event NPL-97-0287, Special Rept:On 970421,fire Door 106A in DG Bldg,Separating Mechanical Equipment Room from Unit 2,B-train,4KV Switchgear Room,Found in Open Position (Closed But Not Latched)1997-05-21021 May 1997 Special Rept:On 970421,fire Door 106A in DG Bldg,Separating Mechanical Equipment Room from Unit 2,B-train,4KV Switchgear Room,Found in Open Position (Closed But Not Latched) ML20132E0681996-12-17017 December 1996 Ro:On 961114,declared Noble Gas Monitor Inoperable.Caused by Necessary Addl Repairs on Failed Pump & Subsequent re- Testing of Sys.Will Repair P-707A Pump & Perform in-service Test by 961220 ML20080P9591995-03-0303 March 1995 Special Rept:On 950207,control Rod H8 in Control Bank B Dropped.Investigation Revealed No Abnormal Conditions. Decision Was Made to Recover Dropped Rod ML20099B9551992-07-29029 July 1992 Ro:Fire Penetration Seal Degraded & Inoperable for More than 7 Days.Caused by Voids in Seal Structure.Hourly Fire Watch Established & Mod to Seal Completed on 920720 ML20195B7271988-10-26026 October 1988 Special Rept:On 880831,emergency Diesel Generator Unexpectedly Returned to Full Speed & Voltage Condition. on 880929 & 1012,event Recurred.Exact Cause Not Determined. Addl Testing Planned Over Next 90 Days to Pinpoint Cause ML20072U4281983-03-30030 March 1983 Ro:On 830308,turbine Trip & Subsequent Reactor Trip Experienced.Caused by Bumping of Main Steam Stop Valve Relay by Contractor Employee While Working on Control Panel. Cleanup Flow Maintained.On 830306,I-131 Limit Exceeded ML20087L1071975-02-0404 February 1975 Telecopy Ro:On 750203,Nuclear Fuel Svcs Spent Fuel Shipping Cask 4B Received & Found in Excess of 22,000 Disintegrations Per Minute 100 Centimeters Squared Removable Contamination on Cask Surface ML20087L1121975-02-0404 February 1975 RO 75-2:on 750224,test of Containment Purge Inlet & Exhaust Valves Closing Time Disclosed That Valves 1CV-3212 & 1CV-3244 Exceeded 3-5 Min Closing Time.Caused by Sticking Pneumatic Relays in Valve Air Operators ML20087L1881975-01-24024 January 1975 Ro:On 741219,discovered That One Insp of Station Batteries Not Completed within Prescribed 30 Day Frequency or within Allowable 25% Grace Period.Caused by Scheduling Difficulty Due to New Supervisor ML20087L6331974-02-0606 February 1974 Ro:On 740102,during Quarterly Functional Testing of Emergency Diesel Backup Relays 4D,fast Start Backup Relays SFB1 & SFB2 Would Not Perform Intended Function.Caused by Neoprene Bellows in Timing Chamber ML20085M3951973-10-29029 October 1973 Ro:Describing Possible Backseating Disc Mislocation Problem on 2-inch Darling Valves on S-350 Wdd Welding End.Valves Repaired.Valve Stems Will Be Changed During Next Refueling Outage ML20087L6351973-05-14014 May 1973 Ro:On 730303 & 0426,test of Undervoltage Relays of 1A01 & 1A02 Nonsafeguards Bus Undervoltage Relays Disclosed Three Out of Four Malfunctional.Caused by Setting of Shaft in Guide Bearing.Relays Removed & Returned to Vendor for Exam ML20087L6551973-03-0909 March 1973 Ro:On 730208,during Performance of Functional Test on Purge Valves,Two Containment Purge Inlet Valves Open When Placing Manual Switch to Open Position But Did Not Close.Caused by Loose Screw on Switch.Mod Made to Valve Circuits 1998-03-30
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARNPL-99-0569, Monthly Operating Repts for Sept 1999 for Pbnp,Units 1 & 2. with1999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for Pbnp,Units 1 & 2. with ML20212D5961999-09-15015 September 1999 Safety Evaluation Supporting Licensee IPEEE Process.Plant Has Met Intent of Suppl 4 to GL 88-20 NPL-99-0051, Monthly Operating Repts for Aug 1999 for Pbnp,Units 1 & 2. with1999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for Pbnp,Units 1 & 2. with NPL-99-0449, Monthly Operating Repts for July 1999 for Pbnp,Units 1 & 2. with1999-07-31031 July 1999 Monthly Operating Repts for July 1999 for Pbnp,Units 1 & 2. with ML20196J4251999-06-30030 June 1999 Safety Evaluation Authorizing Proposed Alternatives Described in Relief Requests VRR-01,ROJ-16,PRR-01 & VRR-02 ML20209D2691999-06-30030 June 1999 Monthly Operating Repts for June 1999 for Pbnps,Units 1 & 2 ML20196F3341999-06-22022 June 1999 Safety Evaluation for Implementation of 422V+ Fuel Assemblies at Pbnp Units 1 & 2 ML20195F9781999-06-10010 June 1999 Unit 2 Refueling 23 Inservice Insp Summary Rept for Form NIS-1 ML20209D2751999-05-31031 May 1999 Revised MORs for May 1999 for Pbnps,Units 1 & 2 NPL-99-0328, Monthly Operating Repts for May 1999 for Pbnp,Units 1 & 2. with1999-05-31031 May 1999 Monthly Operating Repts for May 1999 for Pbnp,Units 1 & 2. with NPL-99-0273, Monthly Operating Repts for Apr 1999 for Point Beach Nuclear Plant,Units 1 & 2.With1999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for Point Beach Nuclear Plant,Units 1 & 2.With ML20196F3521999-04-30030 April 1999 Non-proprietary WCAP-14788, W Revised Thermal Design Procedure Instrument Uncertainty Methodology for Wepc Point Beach Units 1 & 2 (Fuel Upgrade & Uprate to 1656 Mwt - NSSS Power) NPL-99-0193, Monthly Operating Repts for Mar 1999 for Pbnp,Units 1 & 2. with1999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for Pbnp,Units 1 & 2. with NPL-99-0134, Monthly Operating Repts for Feb 1999 for Pbnp,Units 1 & 2. with1999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for Pbnp,Units 1 & 2. with ML20207D6751999-02-22022 February 1999 Assessment of Design Info on Piping Restraints for Point Beach Nuclear Plant,Units 1 & 2.Staff Concludes That Licensee Unable to Retrieve Original Analyses That May Have Been Performed to Justify Removal of Shim Collars ML20206R9001999-01-13013 January 1999 SER Accepting Nuclear Quality Assurance Program Changes for Point Beach Nuclear Plant,Units 1 & 2 NPL-99-0008, Monthly Operating Repts for Dec 1998 for Pbnp,Units 1 & 2. with1998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for Pbnp,Units 1 & 2. with NPL-99-0091, 1998 Annual Results & Data Rept for Pbnps,Units 1 & 2. with1998-12-31031 December 1998 1998 Annual Results & Data Rept for Pbnps,Units 1 & 2. with ML20198C7671998-12-10010 December 1998 Safety Evaluation Accepting Licensee Proposed Alternative to ASME BPV Code,1986 Edition,Section XI Requirement IWA-2232, to Use Performance Demonstration Initiative Program During RPV Third 10-yr ISI for Plant,Unit 2 NPL-98-1006, Monthly Operating Repts for Nov 1998 for Point Beach Nuclear Plant,Units 1 & 2.With1998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for Point Beach Nuclear Plant,Units 1 & 2.With ML20195J5101998-11-16016 November 1998 Proposed Revs to Section 1.3 of FSAR for Pbnp QA Program ML20198J5941998-11-0303 November 1998 1998 Graded Exercise,Conducted on 981103 NPL-98-0948, Monthly Operating Repts for Oct 1998 for Point Beach Nuclear Plant,Units 1 & 2.With1998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for Point Beach Nuclear Plant,Units 1 & 2.With NPL-98-0880, Special Rept:On 980913,fire Alarm Control Panels Inoperable for More That Fourteen Days.Troubleshooting of D-401 Panel Following Installation of Replacement Batteries Revealed No Apparent Cause for Spurious Alarms.Panel D-401 Restored1998-10-21021 October 1998 Special Rept:On 980913,fire Alarm Control Panels Inoperable for More That Fourteen Days.Troubleshooting of D-401 Panel Following Installation of Replacement Batteries Revealed No Apparent Cause for Spurious Alarms.Panel D-401 Restored ML20154M9121998-10-14014 October 1998 Unit 1 Refueling 24 Repair/Replacement Summary Rept for Form NIS-2 ML20154L6751998-10-14014 October 1998 Unit 1 Refueling 24 ISI Summary Rept for Form NIS-1 NPL-98-0826, Monthly Operating Repts for Sept 1998 for Point Beach Nuclear Plant,Units 1 & 2.With1998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for Point Beach Nuclear Plant,Units 1 & 2.With ML20151W3851998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for Pbnp Units 1 & 2 NPL-98-0653, Monthly Operating Repts for July 1998 for Point Beach Nuclear Plant,Units 1 & 21998-07-31031 July 1998 Monthly Operating Repts for July 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20151W4471998-07-31031 July 1998 Corrected Page to MOR for July 1998 for Pbnp Unit 2 ML20151W4541998-07-31031 July 1998 Corrected Page to MOR for July 1998 for Pbnp Unit 1 ML20236Q3161998-07-10010 July 1998 Safety Evaluation Accepting Licensee Proposed Alternative to ASME Code Requirements PTP-3-01 & PTP-3-02 ML20236L6771998-07-0707 July 1998 Safety Evaluation Approving Wepco Implementation Program to Resolve USI A-46 at Point Beach NPP Units 1 & 2 NPL-98-0558, Monthly Operating Repts for June 1998 for Pbnp,Units 1 & 21998-06-30030 June 1998 Monthly Operating Repts for June 1998 for Pbnp,Units 1 & 2 ML20151W4261998-06-30030 June 1998 Corrected Page to MOR for June 1998 for Pbnp Unit 2 ML20151W4221998-05-31031 May 1998 Corrected Page to MOR for May 1998 for Pbnp Unit 2 NPL-98-0481, Monthly Operating Repts for May 1998 for Point Beach Nuclear Plant,Units 1 & 21998-05-31031 May 1998 Monthly Operating Repts for May 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20151W4011998-04-30030 April 1998 Corrected Page to MOR for April 1998 for Pbnp Unit 2 NPL-98-0356, Monthly Operating Repts for April 1998 for Point Beach Nuclear Plant,Units 1 & 21998-04-30030 April 1998 Monthly Operating Repts for April 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20217F3131998-04-17017 April 1998 Safety Evaluation Accepting Proposed Alternative to ASME Code for Surface Exam of Nonstructural Seal Welds,For Plant, Unit 1 ML20216D7071998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20151W3981998-03-31031 March 1998 Corrected Page to MOR for March for Pbnp Unit 2 NPL-98-0209, Special Rept Re Fire Barrier Inoperable for Greater than Seven Days.Compensatory Measures Implemented in Accordance W/Fire Protection Program Requirements During Time That Barriers Were Inoperable1998-03-30030 March 1998 Special Rept Re Fire Barrier Inoperable for Greater than Seven Days.Compensatory Measures Implemented in Accordance W/Fire Protection Program Requirements During Time That Barriers Were Inoperable ML20217A8501998-03-19019 March 1998 SER Accepting Proposed Changes Submitted on 980226 by Wiep to Pbnp Final SAR Section 1.8 Which Will Impact Commitments Made in Pbnp QA Program Description.Changes Concern Approval Authority for Procedures & Interviewing Authority ML20216J0101998-03-17017 March 1998 Safety Evaluation Accepting Third 10-yr Inservice Insp Interval Relief Request RR-1-18 for Plant NPL-98-0159, Monthly Operating Repts for Feb 1998 for Point Beach Nuclear Plant,Units 1 & 21998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20151W3891998-02-28028 February 1998 Corrected Page to MOR for Feb 1998 for Pbnp Unit 2 ML20216D7121998-02-28028 February 1998 Revised Corrected MOR for Feb 1998 for Point Beach Nuclear Plant,Unit 2 NPL-98-0084, Monthly Operating Repts for Jan 1998 for Point Beach Nuclear Plant,Units 1 & 21998-01-31031 January 1998 Monthly Operating Repts for Jan 1998 for Point Beach Nuclear Plant,Units 1 & 2 ML20198L1151998-01-0808 January 1998 SER Accepting Licensee Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Point Beach Nuclear Plant,Units 1 & 2 1999-09-30
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.q Wisconsin
. Electnc POWER COMPANY -
Point Beoch Nuclear Pkint (920) 755 2321 6610 Nuclear Rd., Two Rtvers. WI $4241
- NPL 97-0751 November 21,1997 Document Control Desk '
U.S. NUCLEAR REGULATORY COMMISSION Mail Station PI-137 Washington, DC 20555 1.adies/ Gentlemen:
- DOCKET 50-266 LOW TEMPEllATURE OVERPRESSUIE JULOIECTION. SYSTEM OPERATIQ3 EQINT IlEACll NUCLIL\R PLANT. UNIT 1
'On October 23,1997, an evolution being performed at the Point Beach Nuclear Plant, Unit 1, resulted in the operation of the Low Temperature overpressure Protection System. This occurrence resulted in the momentary p lifting of Pressurizer Power Operated Relief Valve (PORV) 431C which was aligned fbr operation in the low tempermure overpressure protection mode in accordance with Technical Specification 15.3.15.
Attached is a special report for this occurrence as required by Technical Specification 15.6.9.2.C. This Specitication requires a special report to the NRC in the event that the evaluation of the occurrence determines that an overpressurization incident could have occurred had the Low Temperature Overpressure Protection System not been operable. As required by Specification 15.6.9.2.C, this report describes the circumstances .
initiating the transient and corrective actions identified to prevent recurrence. This report summarizes a root cause evaluation of this occurrence and recommended corrective actions.
New commitments that have not been previously docketed are identified ' italics.
If you have any questions regarding the event and our report, please contact us.
Sincerely, r[ % h/r Douglas F. Johnson Manager - Regulatory Services & Licensing 4{b;7
/
Attaclunent 9711290022 971121 PDR ADOCK 05000266.
cc: NRC Resident inspector IE,5EER,l,REl.l ,
. NRC Regional Administrator A muw.,awww twoavatar
Attachment to NPL 97-0751 ,
- ' Page1 DOCKET 50-266-LOW TEMPERATURE OVERPRESSURE J PROTECTION SYSTEM OPERATION-POINT BEACH NUCLEAR PLANT, UNIT I At approximately 1230 on October 23,1997, Unit I operators were in the process of completing OP 4A, "Fihing and Venting Reactor Coolant System." OP 4A directed the operators to OP 4B, " Reactor Coolcnt Pump Operation," to start a reactor coolant pump (RCP). OP-4B has two sections for starting an RCP. OP-4B contains separate directions for starting an RCP dependent on whether the Reactor Coolant System (RCS) loops have previously been filled and vented and for when starting an RCP is necessay for filling and venting an RCS loop. In this case the RCS loops were filled and vented. Unit I was at approximately 350 psig primary pressure,127 F primay temperature, with the RCS in a water-solid condition.
' Between 1230 and 1349, preparations were made to start the pump. These preparations included a pre- '
job briefinvolving the Unit 1 Control Operator, Operating S'ipenisor, third Reactor Operator, Duty Operating Supervisor and was observed by the Duty Shift Supervisor (DSS). The briefing identified that plant conditions necessary for the RCP start were different than previously experienced by the operating crew. The operating crew had started an RCP prior to this event with the plant solid , but it was directly after filling and venting of the RCS with the water in the reactor vessel and loops at approximately the same temperatures. In the existing plant conditions, the water in the reactor vessel was at approximately 127'F and the steam generator temperatures were approximately 70 F. During the brief, the Duty Operating Supervisor noted that approximately three weeks prior, this same evolution, performed by a different crew, resulted in a pressure increase requiring aggressive action by the operator to prevent an f
- overpressure condition. Initial primary pressure for this earlier evolution was approximately 325 psig.
Pressure peaked at approximately 390 psig during this earlier evolution.
At approximately 1349, "A" RCP was started. RCS pressure began to decrease as expected due to cooling of the RCS due to lower temperature water in the Steam Generators. The Unit 1 Control Operator took action to control the pressure decrease by throttling RCS letdown and raising charging pump speed. Primary pressure decreased to approximately 340 psig, and then began to rapidly increase due to reactor coolant pump discharge pressure and charging flow into the water solid RCS exceeding letdown flow by approximately 50 gpm. The control operator, noting the pressure increase, took action to increase letdown flow and decrease charging to control the pressure transient. During this time, the position indication light for RC- 431C flashed on indicating that the PORV had opened and was confirmed _by an associated computer alarm. Pressure was observed by the operating crew to peak between 405 psig and 415 psig. Computer data indicates that the PORV remained open for less than I second.
A calculation performed for this occurrence concluded that, absent operator action to mitigate the pressure increase and absent LTOP actuati in, RCS pressure would hwe reached a level exceeding applicable 10 CFR 50, Appendix G limits within approximately 15 seconds. hierefore, this report is being provided pursuant to Technical Specification 15.6.9.2.C.
The Low Temperature Overpressure Protection System (LTOP) at PBNP utilizes the two installed PORVs. The PORVs are made operational for low pressure relief by utilizing a dual setpoint where the
l Attachment to NPL 97 07,51 Page 2
- low pressure circuit is energized and de-energized by the operator with a keylock switch depending on plant conditions. LTOP made of operation is required to be enabled and operable when RCS temperature is less than 355'F. The PORV lin setpoint during LTOP operation is 415 psig (s; 440 psig is required by th( Technical Specifications). RilR system relief valves are also available to limit RCS pressure when the RilR system is aligned for shutdown cooling.
The root cause evaluation performed for this occurrence determined that the root cause of this event was starting the reactor coolant pump with a water solid reactor coolant system at 350 psig and misoperation of the charging and letdown systems. We concluded that the operating crew did not have a complete undetstanding of the magnitude of the pressure transient expected resulting in an overaggressive response to the pressure decrease immediately following the RCP start.
Contributing to this occurrence were procedure inadequacies. OP 411," Reactor Coolant Pump Operation," does not provide clear guidas:e on minimum RCS pressure required to start an RCP with the RCS solid. OP 4 A," Filling and Venting Reactor Coolant System," requires RCS pressure to be between 325 psig and 400 psig prior to starting an RCP OP 4B states that the 325 psig minimum pressure for starting an RCP is not applicable during oti.ut than fill and vent operations, but has the operator check pressure gicater than 325 psig immediately aner starting the pump. If the pump had been started at less than 325 psig, and .hcre had been no misoperation of the charging and letdown systems, it is likely that the LTCP operation muld have been prevented.
The following corrective actions are being taken:
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- 1. By March 13,1998, operatin); personnel will be briefed on this event. The briefing willinclude how to idennfy abnormal evem precursors and will reinforce the need to maintain a questioning ?
attitude.
- 2. OP-4B, " Reactor Coolant Pump Operation, " will be revised by December 13,1997.
- 3. Licensed operators will be provided training on reactor coolant pump operations in solidplant conditians with various loop and steam generator temperature differences and on control of the chemical and volume control system during solidplant conditions. Training v 31 be completed by March 15,1998, l
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