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Category:NRC Information Notice
MONTHYEARInformation Notice 2008-11, Service Water System Degradation at Brunswicksteam Electric Plant Unit 12008-06-18018 June 2008 Service Water System Degradation at Brunswicksteam Electric Plant Unit 1 Information Notice 1999-28, Recall of Star Brand Fire Protection Sprinkler Heads1999-09-30030 September 1999 Recall of Star Brand Fire Protection Sprinkler Heads Information Notice 1999-27, Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units1999-09-0202 September 1999 Malfunction of Source Retraction Mechanism in Cobalt-60 Teletherapy Treatment Units Information Notice 1999-26, Safety and Economic Consequences of Misleading Marketing Information1999-08-24024 August 1999 Safety and Economic Consequences of Misleading Marketing Information Information Notice 1999-25, Year 2000 Contingency Planning Activities1999-08-10010 August 1999 Year 2000 Contingency Planning Activities Information Notice 1999-24, Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices1999-07-12012 July 1999 Broad-Scope Licensees' Responsibilities for Reviewing and Approving Unregistered Sealed Sources and Devices Information Notice 1999-23, Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices1999-07-0606 July 1999 Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices Information Notice 1999-22, 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion1999-06-25025 June 1999 10CFR 34.43(a)(1); Effective Date for Radiographer Certification and Plans for Enforcement Discretion Information Notice 1999-21, Recent Plant Events Caused by Human Performance Errors1999-06-25025 June 1999 Recent Plant Events Caused by Human Performance Errors Information Notice 1999-20, Contingency Planning for the Year 2000 Computer Problem1999-06-25025 June 1999 Contingency Planning for the Year 2000 Computer Problem Information Notice 1999-19, Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant1999-06-23023 June 1999 Rupture of the Shell Side of a Feedwater Heater at the Point Beach Nuclear Plant Information Notice 1999-18, Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders1999-06-14014 June 1999 Update on Nrc'S Year 2000 Activities for Material Licensees and Fuel Cycle Licensees and Certificate Holders Information Notice 1999-17, Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses1999-06-0303 June 1999 Problems Associated with Post-Fire Safe-Shutdown Circuit Analyses Information Notice 1999-16, Federal Bureau of Investigation'S Nuclear Site Security Program1999-05-28028 May 1999 Federal Bureau of Investigation'S Nuclear Site Security Program Information Notice 1999-15, Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis1999-05-27027 May 1999 Misapplication for 10CFR Part 71 Transportation Shipping Cask Licensing Basis to 10CFR Part 50 Design Basis Information Notice 1999-14, Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick1999-05-0505 May 1999 Unanticipated Reactor Water Draindown at Quad Cities Unit 2, Arkansas Nuclear One Unit 2, & FitzPatrick Information Notice 1999-13, Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs1999-04-29029 April 1999 Insights from NRC Inspections of Low-and Medium-Voltage Circuit Breaker Maintenance Programs Information Notice 1999-12, Year 2000 Computer Systems Readiness Audits1999-04-28028 April 1999 Year 2000 Computer Systems Readiness Audits Information Notice 1999-11, Incidents Involving the Use of Radioactive Iodine-1311999-04-16016 April 1999 Incidents Involving the Use of Radioactive Iodine-131 Information Notice 1999-08, Urine Specimen Adulteration1999-03-26026 March 1999 Urine Specimen Adulteration Information Notice 1999-09, Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-9991999-03-24024 March 1999 Problems Encountered When Manually Editing Treatment Data on the Nucletron Microselectron-HDR (New) Model 105-999 Information Notice 1999-07, Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems1999-03-22022 March 1999 Failed Fire Protection Deluge Valves & Potential Testing Deficiencies in Preaction Sprinkler Systems Information Notice 1999-06, 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions as a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-06, 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements1999-03-19019 March 1999 1998 Enforcement Sanctions As a Result of Deliberate Violations of NRC Employee Protection Requirements Information Notice 1999-05, Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration1999-03-0808 March 1999 Inadvertent Discharge of Carbon Dioxide Fire Protection System and Gas Migration Information Notice 1999-04, Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures1999-03-0101 March 1999 Unplanned Radiation Exposures to Radiographers, Resulting from Failures to Follow Proper Radiation Safety Procedures Information Notice 1999-03, Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake)1999-01-29029 January 1999 Exothermic Reactors Involving Dried Uranium Oxide Powder (Yellowcake) Information Notice 1999-02, Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources1999-01-21021 January 1999 Guidance to Users on the Implementation of a New Single-Source Dose-Calculation Formalism and Revised Air-Kerma Strength Standard for Iodine-125 Sealed Sources Information Notice 1999-01, Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit1999-01-20020 January 1999 Deterioration of High-Efficiency Particulate Air Filters in a Pressurized Water Reactor Containment Fan Cooler Unit Information Notice 1998-45, Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds1998-12-15015 December 1998 Cavitation Erosion of Letdown Line Orifices Resulting in Fatigue Cracking of Pipe Welds Information Notice 1998-44, Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping1998-12-10010 December 1998 Ten-Year Inservice Inspection (ISI) Program Update for Licensees That Intend to Implement Risk-Informed ISI of Piping Information Notice 1998-43, Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping1998-12-0404 December 1998 Leaks in Emergency Diesel Generator Lubricating Oil & Jacket Cooling Water Piping Information Notice 1998-42, Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements1998-12-0101 December 1998 Implementation of 10 CFR 55.55a(g) Inservice Inspection Requirements Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators from Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators from Design Oversight Information Notice 1998-41, Spurious Shutdown of Emergency Diesel Generators From Design Oversight1998-11-20020 November 1998 Spurious Shutdown of Emergency Diesel Generators From Design Oversight Information Notice 1998-39, Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 19971998-10-30030 October 1998 Summary of Fitness-for-Duty Program Performance Reports for Calendar Years 1996 and 1997 Information Notice 1998-40, Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents1998-10-26026 October 1998 Design Deficiencies Can Lead to Reduced ECCS Pump Net Positive Suction Head During Design-Basis Accidents Information Notice 1990-66, Incomplete Draining and Drying of Shipping Casks1998-10-25025 October 1998 Incomplete Draining and Drying of Shipping Casks Information Notice 1998-38, Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections1998-10-15015 October 1998 Metal-Clad Circuit Breaker Maintenance Issues Identified by NRC Inspections Information Notice 1998-37, Eligibility of Operator License Applicants1998-10-0101 October 1998 Eligibility of Operator License Applicants Information Notice 1998-36, Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems1998-09-18018 September 1998 Inadequate or Poorly Controlled, Non-Safety-Related Maintenance Activities Unnecessarily Challenged Safety Systems Information Notice 1998-33, NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities1998-08-28028 August 1998 NRC Regulations Prohibit Agreements That Restrict or Discourage an Employee from Participating in Protected Activities Information Notice 1998-34, Configuration Control Errors1998-08-28028 August 1998 Configuration Control Errors Information Notice 1998-31, Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 21998-08-18018 August 1998 Fire Protection System Design Deficiencies and Common-Mode Flooding of Emergency Core Cooling System Rooms at Washington Nuclear Project Unit 2 Information Notice 1998-30, Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders1998-08-12012 August 1998 Effect of Year 2000 Computer Problem on NRC Licensees and Certificate Holders Information Notice 1998-29, Predicted Increase in Fuel Rod Cladding Oxidation1998-08-0303 August 1998 Predicted Increase in Fuel Rod Cladding Oxidation Information Notice 1998-28, Development of Systematic Sample Plan for Operator Licensing Examinations1998-07-31031 July 1998 Development of Systematic Sample Plan for Operator Licensing Examinations Information Notice 1998-26, Settlement Monitoring and Inspection of Plant Structures Affected by Degradation of Porous Concrete Subfoundations1998-07-24024 July 1998 Settlement Monitoring and Inspection of Plant Structures Affected by Degradation of Porous Concrete Subfoundations Information Notice 1998-27, Steam Generator Tube End Cracking1998-07-24024 July 1998 Steam Generator Tube End Cracking Information Notice 1998-25, Loss of Inventory from Safety-Related Closed-Loop Cooling Water Systems1998-07-0808 July 1998 Loss of Inventory from Safety-Related Closed-Loop Cooling Water Systems 2008-06-18
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ML081120649 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION WASHINGTON, DC 20555-0001 June 18, 2008 NRC INFORMATION NOTICE 2008-11: SERVICE WATER SYSTEM DEGRADATION AT BRUNSWICK STEAM ELECTRIC PLANT UNIT 1
ADDRESSEES
All holders of operating licenses for nuclear power reactors, except those who have permanently ceased operations and have certified that fuel has been permanently removed from the reactor vessel.
PURPOSE
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to inform addressees of recent service water problems experienced at the Brunswick Steam Electric Plant (Brunswick) Unit 1. It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar problems. However, suggestions contained in this IN are not NRC requirements; therefore, no specific action or written response is required.
DESCRIPTION OF CIRCUMSTANCES
The licensee at Brunswick Unit 1 recently encountered problems with the service water system, including failure of one of the supply valves to the residual heat removal (RHR) service water system, an RHR service water pump that was rendered inoperable by foreign material, and flow degradation to a safety-related room cooler.
On July 26, 2007, the 1B loop RHR service water supply motor-operated butterfly valve failed to open while operators were attempting to place the B loop RHR service water pumps in service. This caused the 1B and 1D RHR service water pumps to trip on low suction pressure. The
failure of this 24-inch Fisher Series 7600 butterfly valve was due to the loss of two taper pins used to connect the valve stem to the valve disc. Taper pins are impact-driven into holes in the valve stem and disc and are intended to hold them together through an interference fit. The licensee determined that the most likely cause of the failure was that the taper pins had not been completely driven into the holes during valve refurbishment, which allowed the pins to become displaced during operation.
The licensee had previously reviewed operating experience, including NRC IN 2005-23, "Vibration-Induced Degradation of Butterfly Valves," dated August 1, 2005, which showed that vibration could cause these pins to come loose over time, and had determined that no action was necessary based on different operating conditions, periodic valve inspections, and valve assembly conducted in accordance with vendor recommendations. In light of the July 26, 2007, valve failure, licensee corrective actions included welding or staking any service water valve taper pin that was vulnerable to loss (i.e., becoming dislodged and carried downstream). In
addition, the licensee revised their valve maintenance procedures to specify staking or welding taper pins on these valves during refurbishment.
RHR Service Water Pump Failure
Following identification of the two missing taper pins from the loop B RHR service water supply valve, the licensee attempted to find and retrieve both pins, but could only locate one. The licensee's operability evaluation concluded the system was operable based on their determination that the pin had passed through the RHR service water pumps to the 1B RHR heat exchanger, where it would remain in the heat exchanger's service water inlet endbell. The licensee based this conclusion, in part, on bench testing they conducted which consisted of dropping a spare taper pin through a stationary pump impeller.
On August 21, 2007, the 1D RHR service water pump seized during a start attempt. The licensee's investigation identified that the pump failure was the result of the missing taper pin from the loop B RHR service water supply motor-operated valve becoming lodged between the pump casing and impeller. During their evaluation of the missing taper pin, the licensee had not
contacted the vendor to assist in determining whether the taper pin would pass through an operating pump. During subsequent discussions, the vendor indicated that based on the pump's internal clearances, they could not predict if a taper pin would pass through. Licensee corrective actions included replacing the rotating element for the 1D RHR service water pump.
Service Water Flow Decrease to RHR Room Cooler
On August 2, 2007, operators identified that service water cooling flow through the 1B RHR room cooler had decreased from a normal value of 380 gallons per minute (1438 liters per minute) to 250 gallons per minute (946 liters per minute). Flow continued to decrease, and the
cooler and the B RHR loop were declared inoperable on August 16, 2007. The licensee opened the cooler for inspection and found foreign material in the cooler inlet piping consisting of rubber lining material from a Fisher Model 9100 butterfly valve. Because there was only one valve of this type upstream of the affected cooler, the licensee concluded that all the material came from this valve and had been removed during cooler cleaning. The valve was tagged closed to
prevent the release of additional material and an operability evaluation was completed. The licensee's operability evaluation concluded that the service water system was operable but degraded, and that normal system monitoring would be effective at discovering any unrecovered foreign material.
At Brunswick, there have been a number of failures of Fisher Model 9100 butterfly valve rubber liners dating back to 1985 and most recently at Unit 1 in 2004. The valve believed to be the
source of the material had not been internally inspected, and the NRC inspectors questioned the licensee's operability conclusion, given the possibility that the foreign material could have come from historical valve lining failures and that additional foreign material from these previous failures could remain in the system. On September 9, 2007, the licensee decided to shut down Unit 1 to inspect portions of the service water system. This decision was based on the failure of the 1D RHR service water pump and inoperability of the 1B RHR room cooler. The licensee inspected the valve believed to be the source of the foreign material and found that its rubber
lining was intact. Additional foreign material, in the form of rubber valve lining, oyster shells, and two pieces of service water strainer tie rod with retaining nuts, was identified during these inspections. The licensee removed the foreign material and completed a subsequent operability determination to demonstrate that the service water system was operable prior to plant restart.
An NRC special inspection team reviewed the circumstances surrounding these issues. The team identified that the service water system problems experienced at Brunswick occurred because the licensee did not take adequate corrective actions to remove foreign material from the system and did not perform an adequate loose parts analysis and operability evaluation once foreign material was identified. Additional information is available in NRC Special Inspection Report 05000324/2007-011 and 05000325/2007-011, dated November 16, 2007, and can be found on the NRC's public website in the Agencywide Documents Access and
Management System (ADAMS), under Accession No. ML073200779.
BACKGROUND
Related NRC Generic Communications
NRC IN 2005-23, "Vibration-Induced Degradation of Butterfly Valves," dated August 1, 2005 (ADAMS Accession No. ML051740299). This IN was written to alert addressees to failure of Fisher butterfly valves in the component cooling water system at San Onofre Nuclear Generating Station. Two of the taper pins used to hold the stem to the disc came loose, preventing valve operation. Similar failures had been reported at Davis-Besse Nuclear Power Station and Turkey Point Nuclear Power Plant with valves manufactured by Flowserve and Henry Pratt Company, respectively.
DISCUSSION
Licensees are required to have an operable service water system as specified in plant technical specifications. The Brunswick Unit 1 service water problems were the result of the loss of two taper pins from a Fisher service water system butterfly valve, historical degradation of Fisher butterfly valve lining material, and failure to adequately assess the impact of foreign material in
the system.
CONTACT
This information notice requires no specific action or written response. Please direct any
questions about this matter to the technical contacts listed below or the appropriate Office of Nuclear Reactor Regulation project manager.
/RA by MMaxin for/
Michael J. Case, Director Division of Policy and Rulemaking Office of Nuclear Reactor Regulation
Technical Contacts: Gerald Wilson, RII Gregory Bowman, NRR/DIRS 404-562-4613 301-415-2939 E-mail: gerald.wilson@nrc.gov E-mail: gregory.bowman@nrc.gov
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, by going to the Electronic Reading Room and then to Document Collections.
CONTACT
This information notice requires no specific action or written response. Please direct any
questions about this matter to the technical contacts listed below or the appropriate Office of Nuclear Reactor Regulation project manager.
/RA by MMaxin for/
Michael J. Case, Director Division of Policy and Rulemaking Office of Nuclear Reactor Regulation
Technical Contacts: Gerald Wilson, RII Gregory Bowman, NRR/DIRS 404-562-4613 301-415-2939 E-mail: gerald.wilson@nrc.gov E-mail: gregory.bowman@nrc.gov
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, by going to the Electronic Reading Room and then to Document Collections.
Distribution
- IN r/f *Concurred via email
ADAMS Accession Number: ML081120649OFFICE DIRS/IOEB** TECH EDITOR* BC/DIRS/IOEB** D/NRR/DIRS NAME GBowman CHsu MRoss-Lee FBrown DATE 05/14/08 04/18/08 05/15/08 06/11/08 OFFICE DPR/PGCB DPR/PGCB BC/DPR/PGCB D/NRR/DPR NAME DBeaulieu CHawes MMurphy MCase DATE 06/5/08 06/18/08 06/18/08 06/18/08 OFFICIAL RECORD COPY
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list | - Information Notice 2008-02, Findings Identified During NRC Component Design Bases Inspections (19 March 2008, Topic: Stroke time, Past operability, Battery sizing)
- Information Notice 2008-04, Counterfeit Parts Supplied to Nuclear Power Plants (7 April 2008, Topic: Time of Discovery)
- Information Notice 2008-04, Recent Counterfeit Valves and Circuit Breakers Supplied to Nuclear Power Plants (7 April 2008, Topic: Time of Discovery)
- Information Notice 2008-05, Fires Involving Emergency Diesel Generators Exhaust Manifolds (12 April 2008, Topic: Temporary Modification, Wrench tight)
- Information Notice 2008-06, Instrument Air System Failure Resulting in Manual Reactor Trip (10 April 2008)
- Information Notice 2008-07, Cracking Indications In Thermally Treated Alloy 600 Steam Generator Tubes And Tube-To-Tubesheet Welds (24 April 2008)
- Information Notice 2008-07, Cracking Indications in Thermally Treated Alloy 600 Steam Generator Tubes and Tube-To-Tubesheet Welds (24 April 2008)
- Information Notice 2008-10, Response to Indications of Potential Tampering, Vandalism, or Malicious Mischief (1 May 2008, Topic: Coatings, TheraSphere)
- Information Notice 2008-10, Response to Indications of Potential Tampering Vandalism or Malicious Mischief (1 May 2008, Topic: Coatings, TheraSphere)
- Information Notice 2008-11, Service Water System Degradation at Brunswicksteam Electric Plant Unit 1 (18 June 2008)
- Information Notice 2008-12, Reactor Trip Due to Off-Site Power Fluctuation (7 July 2008)
- Information Notice 2008-14, Criticality Safety-related Events Resulting from Fissile Material Operations under Procedures Not Reviewed by Criticality Safety Staff (29 July 2008, Topic: Uranium Hexafluoride)
- Information Notice 2008-14, Criticality Safety-related Events Resulting from Fissile Material Operations Under Procedures Not Reviewed by Criticality Safety Staff (29 July 2008, Topic: Uranium Hexafluoride)
- Information Notice 2008-16, Summary of Fitness-for-Duty Program Performance Reports for Calendar Year 2007 (2 September 2008, Topic: Fitness for Duty)
- Information Notice 2008-17, Construction Experience with Concrete Placement Process (22 October 2008, Topic: Condition Adverse to Quality)
- Information Notice 2008-18, Loss of Safety-Related Motor Control Center Due to Bus Fault (1 December 2008, Topic: Safe Shutdown)
- Information Notice 2008-20, Failures of Motor Operated Valve Actuator Motors with Magnesium Alloy Rotors (8 December 2008, Topic: Packing leak)
- Information Notice 2008-20, Failures of Motor Operated Valve Actuator Motors With Magnesium Alloy Rotors (8 December 2008)
- Information Notice 2008-21, Impact of Non-Safety Electrical Support System Vulnerabilities on Safety Systems (24 November 2008)
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