Letter Sequence Other |
---|
|
|
MONTHYEARML0617907382006-07-26026 July 2006 Letter, Response to Bulletin 93-02, Debris Plugging of Emergency Core Cooling Suction Strainers Project stage: Other 2006-07-26
[Table View] |
|
---|
Category:Letter
MONTHYEARML24219A0272024-08-0606 August 2024 Response to NRC Regulatory Issue Summary 2024-01, Preparation and Scheduling of Operator Licensing Examinations IR 05000259/20244022024-08-0606 August 2024 Security Baseline Inspection Report 05000259/2024402 and 05000260/2024402 and 05000296/2024402 IR 05000259/20240022024-08-0202 August 2024 Brown Ferry Nuclear Plant – Integrated Inspection Report05000259/2024002 and 05000260/2024002 and 05000296/2024002 ML24199A0012024-07-22022 July 2024 Clarification and Correction to Exemption from Requirement of 10 CFR 37.11(c)(2) ML24172A1342024-07-15015 July 2024 Exemptions from 10 CFR 37.11(C)(2) (EPID L-2023-LLE-0024) - Letter ML24183A4142024-07-10010 July 2024 – License Renewal Regulatory Limited Scope Audit Regarding the Environmental Review of the License Renewal Application (EPID Number: L-2024-SLE-0000) (Docket Numbers: 50-259, 50-260, and 50-296) ML24184A1142024-07-0202 July 2024 Site Emergency Plan Implementing Procedure Revision ML24183A3842024-07-0101 July 2024 Registration of Use of Cask to Store Spent Fuel (MPC-364, -365) ML24179A0282024-06-26026 June 2024 Evaluation of Effects of Out-of-Limits Condition as Described in IWB-3720(a) ML24175A0042024-06-23023 June 2024 Interim Report of a Deviation or Failure to Comply Associated with a Valve in the Unit 3 High Pressure Coolant Injection System ML24176A1132024-06-23023 June 2024 American Society of Mechanical Engineers, Section XI, Fourth 10 Year Inspection Interval, Inservice Inspection, System Pressure Test, Containment Inspection, and Repair and Replacement Programs, Owner’S Activity Report Cycle 21 Oper ML24155A0042024-06-18018 June 2024 Proposed Alternative to the Requirements of the ASME Code (Revised Alternative Request 0-ISI-47) ML24158A5312024-06-0606 June 2024 Registration of Use of Cask to Store Spent Fuel (MPC-361, -362, -363) IR 05000259/20244032024-05-22022 May 2024 – Security Baseline Report 05000259/2024403 and 05000260/2024403 and 05000296/2024403 ML24141A0482024-05-17017 May 2024 EN 56958_1 Ametek Solidstate Controls, Inc ML24136A0702024-05-15015 May 2024 2023 Annual Radiological Environmental Operating Report IR 05000259/20240012024-05-14014 May 2024 Integrated Inspection Report 05000259/2024001, 05000260/2024001, and 05000296/2024001 CNL-24-040, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2024-05-0808 May 2024 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML24123A2012024-05-0202 May 2024 NRC Cybersecurity Baseline Inspection (NRC Inspection Report 05000259/2024404, 05000260-2024404, 05000296/2024404) and Request for Information ML24122A6852024-05-0101 May 2024 2023 Annual Radioactive Effluent Release Report and Offsite Dose Calculation Manual ML24116A2522024-04-25025 April 2024 Site Emergency Plan Implementing Procedure Revision CNL-24-036, – 10 CFR 50.46 Annual Report2024-04-25025 April 2024 – 10 CFR 50.46 Annual Report CNL-24-037, Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 422024-04-22022 April 2024 Clinch River, Sequoyah, Units 1 and 2, Watts Bar, Unit 1 and 2, Nuclear Quality Assurance Plan, TVA-NQA-PLN89-A, Revision 42 CNL-24-024, Hydrologic Engineering Center River Analysis System Project Milestone Status Update2024-04-17017 April 2024 Hydrologic Engineering Center River Analysis System Project Milestone Status Update CNL-24-033, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2024-04-17017 April 2024 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML24032A4762024-02-0101 February 2024 Final Report of a Part 21 Evaluation Associated with Starter Contactors for the BFN Unit 1 High Pressure Coolant Injection Suppression Pool Inboard Suction Valve ML24023A2802024-01-23023 January 2024 Final Report of a Deviation or Failure to Comply Associated with a Relay in the Reactor Core Isolation Cooling Condensate Pump CNL-24-017, Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions2024-01-17017 January 2024 Tennessee Valley Authority - Central Emergency Control Center Emergency Plan Implementing Procedure and Emergency Preparedness Department Procedure Revisions ML24016A3042024-01-16016 January 2024 Final Report of a Part 21 Evaluation Associated with Check Valve 0-CKV-023-0565 for D1 Residual Heat Removal Service Water Pump CNL-23-071, Response to Request for Additional Information Regarding Browns Ferry Nuclear Plant, Units 1, 2, and 3, Inservice Inspection and Augmented Program Interval Revised Request for Alternative 0-ISI-472024-01-11011 January 2024 Response to Request for Additional Information Regarding Browns Ferry Nuclear Plant, Units 1, 2, and 3, Inservice Inspection and Augmented Program Interval Revised Request for Alternative 0-ISI-47 ML24022A1732024-01-0303 January 2024 Receipt and Availability of the Subsequent License Renewal Application ML23319A1992024-01-0303 January 2024 Issuance of Amendment Nos. 333, 356, and 316 Regarding the Technical Specification Surveillance Requirements 3.4.3.2 and 3.5.1.11 Regarding Safety Relief Valves ML23355A2062023-12-21021 December 2023 Request for Exemption from Enhanced Weapons, Firearms Background Checks, and Security Event Notifications Implementation ML23348A3942023-12-14014 December 2023 Interim Part 21 Report of a Potential Deviation or Failure to Comply Associated with Starter Contactors for the High Pressure Coolant Injection Suppression Pool Inboard Suction Valve IR 05000259/20230102023-12-11011 December 2023 Commercial Grade Dedication Inspection Report 05000259/2023010 and 05000260/2023010 and 05000296/2023010 ML23335A0722023-12-0101 December 2023 Interim Report of a Deviation or Failure to Comply Associated with a Relay in the Unit 2 Reactor Core Isolation Cooling Condensate Pump ML23334A2492023-11-30030 November 2023 Site Emergency Plan Implementing Procedure Revision CNL-23-070, Submittal of Fifth 10-Year Interval Inservice Testing Program Plan2023-11-29029 November 2023 Submittal of Fifth 10-Year Interval Inservice Testing Program Plan ML23331A2532023-11-27027 November 2023 Summary Report for 10 CFR 50.9 Evaluations, Technical Specifications Bases Changes, Technical Requirement Manual Changes, and NRC Commitment Revisions CNL-23-067, Central Emergency Control Center Emergency Plan Implementing Procedure Revisions2023-11-27027 November 2023 Central Emergency Control Center Emergency Plan Implementing Procedure Revisions ML23325A1102023-11-21021 November 2023 Anchor Darling Double Disc Gate Valve Commitment Revision ML23320A2542023-11-16016 November 2023 Interim Part 21 Report of a Deviation or Failure to Comply Associated with Check Valve 0-CKV-023-0565 for D1 Residual Heat Removal Service Water Pump IR 05000259/20230032023-11-13013 November 2023 Integrated Inspection Report 05000259/2023003, 05000260/2023003 and 05000296/2023003 IR 05000259/20230402023-11-0202 November 2023 Supplemental Inspection Supplemental Report 05000259 2023040 and Follow-Up Assessment Letter ML23292A2532023-10-18018 October 2023 BFN 2024-301, Corporate Notification Letter (210-day Ltr) ML23282A0022023-10-0606 October 2023 Interim Part 21 Report of a Deviation or Failure to Comply Associated with Check Valve 0-CKV-023-0565 for D1 Residual Heat Removal Service Water Pump ML23278A0122023-10-0505 October 2023 Updated Final Safety Analysis Report, Amendment 30 ML23271A1702023-09-28028 September 2023 Site Emergency Plan Implementing Procedure Revision ML23270A0702023-09-26026 September 2023 SLRA Pre-Application Meeting Summary 09-13-2023 2024-08-06
[Table view] Category:Safety Evaluation
MONTHYEARML23319A1992024-01-0303 January 2024 Issuance of Amendment Nos. 333, 356, and 316 Regarding the Technical Specification Surveillance Requirements 3.4.3.2 and 3.5.1.11 Regarding Safety Relief Valves ML23205A2132023-09-0808 September 2023 Issuance of Amendment Nos. 332, 355, and 315 Regarding the Revision of Technical Specifications to Adopt TSTF-566-A and TSTF-580-A, Rev. 1 ML23219A1542023-08-17017 August 2023 Request to Use Later Edition of ASME Code for Operation and Maintenance and Alternative Requests BFN-IST-01 Through 05 for the Fifth 10-Year Interval Inservice Testing Program ML23171A8862023-07-24024 July 2023 Issuance of Amend. Nos. 331, 354, and 314; 365 and 359 Regarding Adoption of TSTF-541-A, Add Exceptions to Surveillance Requirements for Valves and Dampers Locked in the Actuated Position ML23116A2472023-05-23023 May 2023 Issuance of Amendment Nos. 330, 353, and 313 Regarding Adoption of TSTF-478, Revision 2 for Combustible Gas Control ML23101A1102023-05-16016 May 2023 Issuance of Amendment Nos. 329, 352, and 312 Regarding Removal of Site Acreage Description from Technical Specifications ML23073A2902023-05-0202 May 2023 Issuance of Amendment Nos. 328, 351, and 311 Adoption of TSTF-505, Revision 2, for Risk-Informed Completion Times and TSTF-439, Revision 2, to Eliminate Second Completion Times ML23054A2902023-03-13013 March 2023 Request for Relief from the Requirements of the ASME Boiler and Pressure Vessel Code Regarding Weld Examination Coverage ML23048A3042023-03-0808 March 2023 Tennessee Valley Authority - Request for Relief from Requirements of ASME Boiler and Pressure Vessel Code Regarding Weld Examination Coverage (EPID L-2022-LLR-0045,-0046,-0047) ML22348A0052023-01-25025 January 2023 Issuance of Amendment Nos. 326, 349, and 309; 363 and 35; 159 and 67 Regarding Adoption of TSTF-554, Revise Reactor Coolant Leakage Requirements ML22349A6472023-01-20020 January 2023 Issuance of Amendment Nos. 325, 348, and 308; 362 and 356; and 158 and 66 Regarding Adoption of TSTF-529, Rev. 4, Clarify Use and Application Rules ML22348A0662023-01-13013 January 2023 Issuance of Amendment Nos. 325, 348, & 308 Regarding Application of Advanced Framatome Methodologies, & Adoption of TSTF Traveler TSTF-564-A, Rev. 2, in Support of Atrium 11 Fuel Use (EPID L-2021-LLA-0132) - Nonproprietary ML22271A9142022-12-0707 December 2022 Issuance of Amendment Nos. 324, 347, and 307; 360 and 354; 157 and 65 Regarding a Revision to the Emergency Action Level Scheme ML22273A1032022-11-22022 November 2022 Issuance of Amendment Nos. 323, 346, and 306 Regarding Chilled Water Cross-Tie Modification ML22220A2602022-11-21021 November 2022 Issuance of Amendment Nos. 322, 345, and 305 Regarding Adoption of TSTF Traveler TSTF-205-A, Rev. 3, and TSTF-563-A ML22298A2852022-11-14014 November 2022 Request for Alternative to American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI, Paragraph IWB-2420(B) and Use of Code Case N-526 ML22138A3252022-06-24024 June 2022 Issuance of Amendment Nos. 321, 344, and 304 Regarding Spent Fuel Pool Criticality Safety Analysis ML22084A0012022-04-0505 April 2022 Clinch River Nuclear Site; Sequoyah Nuclear Plant, Units 1 and 2; Watts Bar Nuclear Plant, Units 1 and 2, Review of Quality Assurance Plan Changes ML22020A2282022-03-16016 March 2022 Issuance of Amendment Nos. 320, 343, and 303 Regarding the Adoption of Approved Technical Specification Task Force Traveler TSTF-568, Revision 2 ML22010A1952022-01-12012 January 2022 Request to Use Later Edition of the American Society of Mechanical Engineers Code for Operation and Maintenance of Nuclear Power Plants ML21285A0682021-10-28028 October 2021 Issuance of Amendment Nos. 319, 342, and 302 Regarding the Adoption of Technical Specification Task Force Traveler TSTF-582, Revision 2 ML21214A1392021-08-30030 August 2021 Issuance of Amendment Nos. 318, 341, and 301 Regarding Changes to Technical Specification 3.8.6, Battery Cell Parameters ML21173A1772021-07-27027 July 2021 Issuance of Amendment Nos. 317, 340, and 300 Regarding Adoption of Title 10 of the Code of Federal Register Section 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components ML21075A0762021-04-30030 April 2021 Issuance of Amendment Nos. 316, 339, and 299 Regarding the Incorporation of the Tornado Missile Risk Evaluator Into the Licensing Basis ML21041A4892021-04-0808 April 2021 Issuance of Amendment Nos. 315, 338, and 298 Regarding the Adoption of Technical Specifications Task Force Traveler, TSTF-425, Revision 3 ML20268A0822021-01-12012 January 2021 Issuance of Amendment Nos. 314, 337, and 297; 351 and 345; 140 and 46 Regarding Changes to the Technical Specifications ML20282A3452020-11-19019 November 2020 Issuance of Amendment Nos. 313, 336, 296, 350, 344, 138, and 44 Revise Emergency Plan On-Shift Emergency Medical Technician & Onsite Ambulance Requirements ML20253A1812020-09-23023 September 2020 Proposed Alternative to the Requirements of the American Society of Mechanical Engineers Code ML20085G8962020-06-26026 June 2020 Issuance of Amendment Nos. 312, 335, and 295 Regarding Request to Revise Emergency Plan Staff Augmentation Times ML19329E3192020-01-0202 January 2020 SE Implementation of Hardened Containment Vents Capable of Operation Under Severe Accident Conditions Related to Order EA-13-109 (CAC Nos. MF4540, MF4541 and MF4542; EPID No. L-2014-JLD-0044) ML19294A0112019-12-26026 December 2019 Issuance of Amendment Nos. 311, 334, and 294 Adopt Technical Specifications Task Force Traveler, TSTF-542, Revision 2 ML18277A1102019-08-27027 August 2019 Units, 1 & 2 Issuance of Amendment Nos. 309, 332, 292, 345, 339, 128, and 31 Regarding Unbalanced Voltage Protection ML19198A0012019-08-13013 August 2019 Issuance of Amendment Nos. 308, 331, and 291 to Extend Implementation Due Date for Modifications 102 and 106 Related to NFPA 805 (Eid L-2019-LLA-0140) ML19037A1372019-04-0202 April 2019 Revisions to Modifications 85, 102 and 106 Related to National Fire Protection Association 805 Performance-based Standard for Fire Protection of Light Water Reactor Electric Generating Plants ML19010A2742019-03-18018 March 2019 Final Safety Evaluation by the Office of Nuclear Reactor Regulation Topical Report- TVA Overall Basin Probable Maximum Precipitation and Local Intense Precipitation, Calculation, CDQ0000002016000041 Tennessee Valley Authority ML19016A2152019-02-28028 February 2019 Relief from the Requirements of American Association of Mechanical Engineers Code Section XI Inservice Inspection Program, Request for an Alternative ISI-46 ML18323A1722018-12-31031 December 2018 Relief Request No. 1 ISI 29 Regarding Second 10-Year Inservice Inspection Interval Regarding Examination Coverage for Certain Pressure Retaining Welds ML18323A0262018-12-0404 December 2018 Relief Request No. 1-ISI-28 Regarding Third 10-Year Inservice Inspection Interval Regarding Examination Coverage for Certain Pressure Retaining Reactor Vessel Welds ML18241A3192018-10-0909 October 2018 Issuance of Amendment Nos. 306, 329, and 289 to Revise Approved NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants-Revision ML18251A0032018-09-27027 September 2018 Issuance of Amendment Nos. 305, 328, and 288 to Revise Technical Specification 5.5.12, Primary Containment Leakage Rate Testing Program (CAC Nos. MG0113, MG0114, and MG0115; EPID L-2017-LLA-0292) ML18236A3312018-09-24024 September 2018 Safety Evaluation Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051 ML18197A3072018-08-30030 August 2018 Issuance of Amendments Regarding Request to Change Technical Specification 3.3.1 and Surveillance Requirement 3.2.4 ML18171A3372018-07-10010 July 2018 Issuance of Amendment to Revise License Condition 2.C(18)(a)3 ML18138A4522018-05-29029 May 2018 Bf, Units 1, 2, and 3; Sequoyah, Units 1 and 2; Watts Bar, Units 1 and 2 - Correction to an Omitted Reference for License Amendment Regarding Request to Upgrade (CAC Nos. MF9054, MF9055, MF9056, MF9057, MF9058, MF9059, and MF9060, EPID L-20 ML17289A0322017-12-22022 December 2017 Issuance of Amendments Regarding Request to Upgrade Emergency Action Level Scheme (CAC Nos. MF9054-60; EPID L2017-LLA-0160) ML17261A0362017-10-0606 October 2017 Request for Request 3-ISI-28 Regarding Third 10-Year Inservice Inspection Interval Examination Coverage of Inside Radius and Nozzle-to-Vessel Welds ML17215A2432017-10-0202 October 2017 Browns Ferry Nuclear Plant, Units 1, 2, and 3; Watts Bar Nuclear Plant, Units 1 and 2 - Issuance of Amendments to Change Technical Specifications to Adopt Technical Specifications Task Force Traveler-522 (CAC No. MF9562-MF9566) ML17032A1202017-08-14014 August 2017 Non-Proprietary Issuance of Amendments Regarding Extended Power Uprate ML17145A5522017-08-11011 August 2017 Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Alternative Request IST-RR-1 for the Fourth 10-Year Inservice Testing Interval (CAC Nos. MF9087, MF9088, and MF9089) ML17034A3602017-03-27027 March 2017 Issuance of Amendment Nos. 298, 322, 282, and 338 and 331 - Revise Technical Specification 5.3, Unit Staff Qualifications to Replace References to Rg 1.8, Rev. 2 with TVA Nuclear Quality ... 2024-01-03
[Table view] |
Text
July 26, 2006 Mr. Karl E. Singer Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
BROWNS FERRY NUCLEAR PLANT, UNIT 1 - REVIEW OF LICENSEE RESPONSE TO NRC BULLETIN 93-02, DEBRIS PLUGGING OF EMERGENCY CORE COOLING SUCTION STRAINERS (TAC NO. MC3393)
Dear Mr. Singer:
By letter dated May 6, 2004 (Agencywide Documents Access and Management System
[ADAMS] Accession Number ML041280583), Tennessee Valley Authority (TVA) provided an updated response to Nuclear Regulatory Commission (NRC) Bulletin 93-02, Debris Plugging of Emergency Core Cooling Suction Strainers for Browns Ferry Nuclear Plant (BFN), Unit 1.
BFN Unit 1 has been in an extended outage since 1985. By letter dated May 23, 1993, TVA committed to perform the requested actions of Bulletin 93-02 prior to restarting BFN Unit 1.
TVA is proposing to return the unit to service and is, therefore, responding to NRC generic communications that were not answered while BFN Unit 1 was shut down. The staff has reviewed the TVAs updated response to NRC Bulletin 93-02 for BFN Unit 1. Our evaluation is attached.
We conclude that TVA has satisfied the recommendations of Bulletin 93-02 to inspect the Browns Ferry Unit 1 primary containment and remove temporary fibrous material, and has also accounted for permanent fibrous material in the design of the upgraded Emergency Core Cooling System suction strainers installed in response to NRC Bulletin 96-03.
If you have any questions, please contact me at (301) 415-4041.
Sincerely,
/RA/
Margaret H. Chernoff, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-259
Enclosure:
Safety Evaluation cc w/encl: See next page
ML061790738 NRR-106 OFFICE LPL2-2/PM LPL2-2/LA ACVB/BC LPL2-2/BC NAME MChernoff BClayton RDennig by memo LRaghavan DATE 7/26/06 7/26/06 5 /15/06 7/26/06 Mr. Karl W. Singer BROWNS FERRY NUCLEAR PLANT Tennessee Valley Authority cc:
Mr. Ashok S. Bhatnagar, Senior Vice President Mr. Robert G. Jones, General Manager Nuclear Operations Browns Ferry Site Operations Tennessee Valley Authority Browns Ferry Nuclear Plant 6A Lookout Place Tennessee Valley Authority 1101 Market Street P.O. Box 2000 Chattanooga, TN 37402-2801 Decatur, AL 35609 Mr. Larry S. Bryant, Vice President Mr. Larry S. Mellen Nuclear Engineering & Technical Services Browns Ferry Unit 1 Project Engineer Tennessee Valley Authority Division of Reactor Projects, Branch 6 6A Lookout Place U.S. Nuclear Regulatory Commission 1101 Market Street 61 Forsyth Street, SW.
Chattanooga, TN 37402-2801 Suite 23T85 Atlanta, GA 30303-8931 Brian OGrady, Site Vice President Browns Ferry Nuclear Plant Mr. Glenn W. Morris, Manager Tennessee Valley Authority Corporate Nuclear Licensing P.O. Box 2000 and Industry Affairs Decatur, AL 35609 Tennessee Valley Authority 4X Blue Ridge Mr. Robert J. Beecken, Vice President 1101 Market Street Nuclear Support Chattanooga, TN 37402-2801 Tennessee Valley Authority 6A Lookout Place Mr. William D. Crouch, Manager 1101 Market Street Licensing and Industry Affairs Chattanooga, TN 37402-2801 Browns Ferry Nuclear Plant Tennessee Valley Authority General Counsel P.O. Box 2000 Tennessee Valley Authority Decatur, AL 35609 ET 11A 400 West Summit Hill Drive Senior Resident Inspector Knoxville, TN 37902 U.S. Nuclear Regulatory Commission Browns Ferry Nuclear Plant Mr. John C. Fornicola, Manager 10833 Shaw Road Nuclear Assurance and Licensing Athens, AL 35611-6970 Tennessee Valley Authority 6A Lookout Place State Health Officer 1101 Market Street Alabama Dept. of Public Health Chattanooga, TN 37402-2801 RSA Tower - Administration Suite 1552 Mr. Bruce Aukland, Plant Manager P.O. Box 303017 Browns Ferry Nuclear Plant Montgomery, AL 36130-3017 Tennessee Valley Authority P.O. Box 2000 Chairman Decatur, AL 35609 Limestone County Commission 310 West Washington Street Mr. Masoud Bajestani, Vice President Athens, AL 35611 Browns Ferry Unit 1 Restart Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION UPDATED BULLETIN 93-02 RESPONSE TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT, UNIT 1 DOCKET NO. 50-259
1.0 INTRODUCTION
By letter dated February 21, 2006 (Agencywide Documents Access and Management System
[ADAMS] Accession Number ML0605206520), the Tennessee Valley Authority (TVA, the licensee) provided an updated response to U.S. Nuclear Regulatory Commission (NRC)
Bulletin 93-02, Debris Plugging of Emergency Core Cooling Suction Strainers, for Browns Ferry Nuclear Plant (BFN), Unit 1.
On May 11, 1993, the NRC issued NRC Bulletin 93-02. This bulletin requested that licensees, immediately upon receiving this bulletin, take the following actions:
Identify fibrous air filters or other temporary sources of fibrous material, not designed to withstand a loss-of-coolant accident (LOCA), which are installed or stored in your primary containment. Take any immediate compensatory measures which may be required to assure the functional capability of the emergency core cooling system (ECCS). Take prompt action to remove any such material. Because of the low probability of a LOCA event, the staff considers removal of this material at the next shutdown, or within 120 days, whichever comes first, to be sufficiently prompt. If the facility is currently in a shutdown, you are requested to remove such material prior to restart.
The requested actions were prompted by the clogging of ECCS suction strainers at the Perry Nuclear Plant, a BWR/6 nuclear steam supply system with a Mark III containment. The material that clogged the ECCS suction strainers consisted of glass fibers from temporary drywell cooling filters that had been inadvertently dropped into the suppression pool.
By letter dated May 23, 1993 (Nuclear Documents System [NUDOCS] Accession Number 9305110015), the licensee stated that Browns Ferry Unit 1 was in an extended outage. The licensee committed to the following prior to Unit 1 restart:
- 1. Unit 1 will be evaluated for permanent fibrous material (note that Bulletin 93-02 did not specifically address permanent fibrous material).
- 2. Unit 1 will be inspected and temporary fibrous material will be removed prior to startup.
- 3. A report confirming completion of the above listed activities (commitments 1 and 2) will be provided (to the NRC) prior to restart.
Enclosure
The NRC issued NRC Bulletin 93-02 Supplement 1 on February 18, 1994. This bulletin requested all holders of operating licenses or construction permits for boiling-water reactors to take appropriate actions to ensure the reliability of the ECCS in view of the information discussed in the bulletin regarding the vulnerability of the ECCS suction strainers to clogging.
2.0 REGULATORY EVALUATION
Title 10 of the Federal Code of Regulations (CFR) Section 50.46(b)(5) requires that adequate ECCS flow be provided to maintain the core temperature at an acceptably low value and to remove decay heat for the extended period of time required by the long-lived radioactivity remaining in the core following a design basis accident. In order to ensure that adequate flow is provided, the buildup of debris on the ECCS suction strainers must remain within the design basis of these strainers. NRC Bulletin 93-02 and NRC Bulletin 93-02 Supplement 1 were issued by the NRC to help ensure that this design basis is satisfied.
3.0 TECHNICAL EVALUATION
By letter dated February 21, 2006, TVA provided an updated response to NRC Bulletin 93-02.
The letter stated that TVA has completed its evaluation of permanent fibrous material in the BFN Unit 1 containment and considers the commitment (item 1 above) closed.
The licensee stated that the only fibrous materials permanently installed in the drywell are insulation materials located in drywell penetrations. TVA determined that, at restart, twelve BFN Unit 1 containment penetrations will have permanently installed insulation consisting of asbestos, calcium silicate and fiberglass. This insulation will be located in the penetrations between the pipe and the penetration sleeve.
NRC Bulletin 96-03 (NUDOCS 9605020119) requested that licensees implement appropriate procedural measures and plant modifications to minimize the potential for clogging of ECCS suppression pool suction strainers. The licensee responded by letter dated July 25, 1997 (NUDOCS 9708050342), and committed to install large passive suction strainers in the suppression pools of all three BFN units. The licensee stated that fibrous debris, including the permanently installed insulation in the piping penetrations, had been accounted for in determining the debris loading on the BFN Unit 2 and Unit 3 ECCS suction strainers. The letter did not specifically state that Unit 1 strainers will be treated in the same way, only that appropriate modifications will be implemented on Unit 1 prior to restart. In the licensees February 21, 2006, letter, the licensee stated that TVA has installed new, high capacity passive strainers on Unit 1, which are of the same design as on Units 2 and 3. Therefore, the licensee has acceptably accounted for permanent fibrous material in Unit 1.
The licensees February 21, 2006, letter also provided the status of compliance with the recommendations of NRC Bulletin 93-02. The licensee states that, Also in accordance with the Units 2 and 3 precedent, TVA has revised its Unit 1 General Operating Instruction on Drywell Closeout to ensure temporary fibrous air filters or other temporary sources of fibrous material are removed.
The NRC staff considers this an acceptable resolution of the licensees commitments to items (2) and (3) above to satisfy Bulletin 93-02.
The licensee previously responded to Bulletin 93-02 Supplement 1 for all three BFN units and notified the NRC of the completion of its commitments by letters dated April 18, 1994 (NUDOCS 9404260335), July 29, 1994 (NUDOCS 9408100119), and December 1, 1994 (NUDOCS 941208139) and the NRC found the licensees resolution of the issues addressed in Bulletion 93-02 Supplement 1 to be acceptable, as stated in the NRCs letter to the licensee dated July 19, 1994 (NUDOCS 9407250211).
4.0 CONCLUSION
The licensee has acceptably complied with the recommendations of NRC Bulletin 93-02. The NRC has previously concurred with the licensees compliance with the recommendations of Supplement 1 to Bulletin 93-02.
Principal Contributor: Richard M. Lobel Date: July 26, 2006