SBK-L-13116, Request for Additional Information Regarding License Amendment Request 13-02,Application to Revise Technical Specifications to Adopt TSTF-510, Revision to Steam Generator Program Inspection Frequencies & Tube
| ML13183A108 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 06/25/2013 |
| From: | Walsh K NextEra Energy Seabrook |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| SBK-L-13116 | |
| Download: ML13183A108 (10) | |
Text
NEXTera ENERGYAM June 25, 2013 10 CFR 50.90 SBK-L-13116 Docket No. 50-443 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Seabrook Station Response to Request for Additional Information Regarding License Amendment Request 13-02, Application to Revise Technical Specifications to Adopt TSTF-5 10, "Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection," Using the Consolidated Line Item Improvement Process
References:
- 1. NextEra Energy Seabrook, LLC letter SBK-L- 13030, "License Amendment Request 13-02, Application to Revise Technical Specifications to Adopt TSTF-5 10, "Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection," Using the Consolidated Line Item Improvement Process," March 27, 2013
- 2. NRC letter "Seabrook Station, Unit I - Request for Additional Information for License Amendment 13-02, Application to Revise Technical Specifications to Adopt TSTF-5 10, "Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection," Using the Consolidated Line Item Improvement Process (TAC No. MF 1372),
June 6, 2013 In Reference 1, NextEra Energy Seabrook, LLC (NextEra) submitted a request for an amendment to the Technical Specifications (TS) for Seabrook Station. The proposed amendment would modify TS requirements regarding steam generator tube inspections and reporting as described in TS Task Force (TSTF)-5 10, Revision 2, "Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection," using the Consolidated Line Item Improvement Process.
In Reference 2, the NRC staff requested additional information in order to complete its review of the license amendment request. The Enclosure to this letter contains NextEra's response to the NPo.
NextEra Energy Seabrook, LLC, P.O. Box 300, Lafayette Road, Seabrook, NH 03874
United States Nuclear Regulatory Commission SBK-L- 13116 / Page 2 request for additional information. Attachment 1 to the Enclosure provides mark-ups of the affected TS pages showing the revised proposed changes, and Attachment 2 contains clean affected TS pages that incorporate the revised proposed TS changes.
The changes to the proposed TS are editorial in nature and do not alter the conclusion in Reference I that the changes do not present a significant hazards consideration.
Should you have any questions regarding this letter, please contact Mr. Michael O'Keefe, Licensing Manager, at (603) 773-7745.
I declare under penalty of perjury that the foregoing is true and correct.
Executed on J'-e, ,* ,2013.
Sincerely, Kev ' . Wsh Site Vice President NextEra Energy Seabrook, LLC Enclosure cc: NRC Region I Administrator NRC Project Manager, Project Directorate 1-2 NRC Senior Resident Inspector Director Homeland Security and Emergency Management New Hampshire Department of Safety Division of Homeland Security and Emergency Management Bureau of Emergency Management 33 Hazen Drive Concord, NH 03305 John Giarrusso, Jr., Nuclear Preparedness Manager The Commonwealth of Massachusetts Emergency Management Agency 400 Worcester Road Framingham, MA 01702-5399
Enclosure Response to Request for Additional Information (RAI)
RAIM Technical Specification 6.7.6.k.b. I does not appear to follow the formatting in TSTF-5 10. Please clarify the reason for the difference since it neither follows TSTF-5 10 nor does it follow standard grammatical practice in that it connects a list of items with "and" rather than using commas and only one "and" at the end of the list.
Response to RAI-1 NextEra proposes to revise the change to TS 6.7.6.k.b. I to follow TSTF-5 10 and standard grammatical practice as shown below.
- 1. Structural integrity performance criterion: All in-service steam generator tubes shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby, and cool down), afid all anticipated transients included in the design specification,) and design basis accidents. This includes retaining a safety factor of 3.0 against burst under normal steady state full power operation primary-to secondary pressure differential and a safety factor of 1.4 against burst applied to the design basis accident primary-to-secondary pressure differentials. Apart from the above requirements, additional loading conditions associated with the design basis accidents, or combination of accidents in accordance with the design and licensing basis, shall also be evaluated to determine if the associated loads contribute significantly to burst or collapse.
In the assessment of tube integrity, those loads that do significantly affect burst or collapse shall be determined and assessed in combination with the loads due to pressure with a safety factor of 1.2 on the combined primary loads and 1.0 on axial secondary loads.
RAI-2
Technical Specification 6.7.6.k.d.2.c is inconsistent with TSTF-5 10. Please modify your proposal to make it consistent with TSTF-5 10 (by adding the word "remaining" before the word "life") or justify the reason for the difference. Please note that as currently written, the requirement under 6.7.6.d.2.c would make the requirement of 6.7.6.d.2.b meaningless since the requirement in 6.7.6.d.2.c is more restrictive and applies for the entire life of the steam generator (regardless of the steam generators' age).
Response to RAI-2 NextEra proposes to revise TS 6.7.6.k.d.2.c for consistency with TSTF-510 as indicated below.
c) During the remaininglife of the SGs, inspect 100 % of the tubes every 72 effective full power months. This constitutes the third and subsequent inspection periods.
Attachment 1 Mark-up of the TS Pages
ADMINISTRATIVE CONTROLS PROCEDURES AND PROGRAMS 6.7.6 (Continued)
- b. Performance criteria for SG tube integrity. SG tube integrity shall be maintained by meeting the performance criteria for tube structural integrity, accident induced leakage, and operational LEAKAGE.
- 1. Structural integrity performance criterion: All in-service steam generator tubes shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby, and ool downall anticipated transients included in the design specificatiorp an design bas)is accidents. This includes retaining a safety factor of 3.0 against burst under normal steady state full power operation primary-to-secondary pressure differential and a safety factor of 1.4 against burst applied to the design basis accident primary-to-secondary pressure differentials. Apart from the above requirements, additional loading conditions associated with the design basis accidents, or combination of accidents in accordance with the design and licensing basis, shall also be evaluated to determine if the associated loads contribute significantly to burst or collapse. In the assessment of tube Integrity, those loads that do significantly affect burst or collapse shall be determined and assessed in combination with the loads due to pressure with a safety factor of 1.2 on the combined primary loads and 1.0 on axial secondary loads.
- 2. Accident induced leakage performance criterion: The primary to secondary accident induced leakage rate for any design basis accident, other than a SG tube rupture, shall not exceed the leakage rate assumed in the accident analysis in terms of total leakage rate for all SGs and leakage rate for an individual SG. Leakage is not to exceed I gpm total or 500 gpd through any one SG.
- 3. The operational LEAKAGE performance criterion is specified in LCO 3.4.6.2, "Reactor Coolant System Operational Leakage."
- c. Provisions for SG tu criteria. Tubes found by inservice inspection to contain flaws with a depth equal to or exceeding 40% of the nominal tube wall thickness shall be plugged.
SEABROOK - UNIT I 6-12 Amendment No. 34,T 14, 09,44-6
ADMINISTRATIVE CONTROLS PROCEDURES AND PROGRAMS 6.7.6 (Continued)
The. following alternate tub r i criteria shall be applied as an alternative to the 40% depth based-criteria:
Tubes with service-induced flaws located greater than 15.21 inches below the top of the tubesheet do not require plugging. Tubes with service-induced [,j flaws located in the portion of the tube from the top of the tubesheet to 15.21 U!
inches below the top of the tubesheet shall be plugged upon detection.
- d. Provisions for SG tube inspections. Periodic SG tube inspections shall be performed. The number and portions of the tubes inspected and methods of inspection shall be performed with the objective of detecting flaws of any type (e.g., volumetric flaws, axial and circumferential cracks) that may be present along the length of the tube, from the tube-to-tubesheet weld at the tube inlet to the tube-to-tubesheet weld at the tube outlet, and that may satisfy the applicable tub criteria. The portion of the tube below 15.21 inches from the top of the tubesheet is excluded from this requirement. The tube-to-tubesheet weld is not part of the tube. In addition to meeting the requirements of d.1, d.2, and d.3 below, the inspection scope, inspection methods, and inspection intervals shall be such as to ensure that SG tube integrity is maintained until the next SG inspection. AP *7 ~-,'/i assessmentý shall be performed to determine the type and location of flaws to which the tubes may be susceptible. and, based on this assessment, to determine which inspection methods need to be employed and at what locations.
- 1. Inspect 100% of the tubes in each SG during the first refueling outage following
- 2. Inspect 100% of tMe tubes at sequental periods of 120, 90, and, therez 60 effective full months. Th_ sequential p *sd shall be considerd egin after the'inservice ins oen of the SGs. In adn1, inspect 50% e tubes by the eling outage near 1e
- dpoint of the peI and the remajig 50% by the refuel outage nearest the end of the period. N G shall operate for re than 48 T effective full power months or two refueling outages (whichever is less) without being inspected.
SEABROOK - UNIT I 6-13 Amendment No. 34, 404, 109, 115, 123,43e4-,
INSERT d.2 After the first refueling outage following SG installation, inspect each SG at least every 48 effective full power months or at least every other refueling outage (whichever results in more frequent inspections). In addition, the minimum number of tubes inspected at each scheduled inspection shall be the number of tubes in all SGs divided by the number of SG inspection outages scheduled in each inspection period as defined in a, b, and c below. If a degradation assessment indicates the potential for a type of degradation to occur at a location not previously inspected with a technique capable of detecting this type of degradation at this location and that may satisfy the applicable tube plugging criteria, the minimum number of locations inspected with such a capable inspection technique during the remainder of the inspection period may be prorated. The fraction of locations to be inspected for this potential type of degradation at this location at the end of the inspection period shall be no less than the ratio of the number of times the SG is scheduled to be inspected in the inspection period after the determination that a new form of degradation could potentially be occurring at this location divided by the total number of times the SG is scheduled to be inspected in the inspection period. Each inspection period defined below may be extended up to 3 effective full power months to include a SG inspection outage in an inspection period and the subsequent inspection period begins at the conclusion of the included SG inspection outage.
a) After the first refueling outage following SG installation, inspect 100% of the tubes during the next 120 effective full power months. This constitutes the first inspection period; b) During the next 96 effective full power months, inspect 100% of the tubes. This constitutes the second inspection period; and c) During the remaining life of the SGs, inspect 100 % of the tubes every 72 effective full power months. This constitutes the third and subsequent inspection periods.
Clean TS Pages
ADMINISTRATIVE CONTROLS PROCEDURES AND PROGRAMS 6.7.6 (Continued)
- b. Performance criteria for SG tube integrity. SG tube integrity shall be maintained by meeting the performance criteria for tube structural integrity, accident induced leakage, and operational LEAKAGE.
- 1. Structural integrity performance criterion: All in-service steam generator tubes shall retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby, and cool down),
all anticipated transients included in the design specification, and design basis accidents. This includes retaining a safety factor of 3.0 against burst under normal steady state full power operation primary-to-secondary pressure differential and a safety factor of 1.4 against burst applied to the design basis accident primary-to-secondary pressure differentials.
Apart from the above requirements, additional loading conditions associated with the design basis accidents, or combination of accidents in accordance with the design and licensing basis, shall also be evaluated to determine if the associated loads contribute significantly to burst or collapse.
In the assessment of tube integrity, those loads that do significantly affect burst or collapse shall be determined and assessed in combination with the loads due to pressure with a safety factor of 1.2 on the combined primary loads and 1.0 on axial secondary loads.
- 2. Accident induced leakage performance criterion: The primary to secondary accident induced leakage rate for any design basis accident, other than a SG tube rupture, shall not exceed the leakage rate assumed in the accident analysis in terms of total leakage rate for all SGs and leakage rate for an individual SG. Leakage is not to exceed 1 gpm total or 500 gpd through any one SG.
- 3. The operational LEAKAGE performance criterion is specified in LCO 3.4.6.2, "Reactor Coolant System Operational Leakage."
- c. Provisions for SG tube plugging criteria. Tubes found by inservice inspection to contain flaws with a depth equal to or exceeding 40%
of the nominal tube wall thickness shall be plugged.
SEABROOK - UNIT 1 6-12 Amendment No. 34, 3-, 104, 109, 115,
ADMINISTRATIVE CONTROLS PROCEDURES AND PROGRAMS 6.7.6 (Continued) technique during the remainder of the inspection period may be prorated. The fraction of locations to be inspected for this potential type of degradation at this location at the end of the inspection period shall be no less than the ratio of the number of times the SG is scheduled to be inspected in the inspection period after the determination that a new form of degradation could potentially be occurring at this location divided by the total number of times the SG is scheduled to be inspected in the inspection period. Each inspection period defined below may be extended up to 3 effective full power months to include a SG inspection outage in an inspection period and the subsequent inspection period begins at the conclusion of the included SG inspection outage.
a) After the first refueling outage following SG installation, inspect 100% of the tubes during the next 120 effective full power months. This constitutes the first inspection period; b) During the next 96 effective full power months, inspect 100% of the tubes. This constitutes the second inspection period; and c) During the remaining life of the SGs, inspect 100 % of the tubes every 72 effective full power months. This constitutes the third and subsequent inspection periods.
- 3. If crack indications are found in portions of the SG tube not excluded above, then the next inspection for each affected and potentially affected SG for the degradation mechanism that caused the crack indication shall not exceed 24 effective full power months or one refueling outage (whichever results in more frequent inspections). If definitive information, such as from examination of a pulled tube, diagnostic non-destructive testing, or engineering evaluation indicates that a crack-like indication is not associated with a crack(s), then the indication need not be treated as a crack.
- e. Provisions for monitoring operational primary to secondary leakage.
SEABROOK - UNIT 1 6-14 Amendment No. 3, 7-8, 190, 115, 110, 23,