NL-09-1411, License Amendment Request to Revise Technical Specification (TS) Sections 5.5.9, Steam Generator (SG) Program and TS 5.6.10, Steam Generator Tube Inspection Report for Interim Alternate Repair Criteria
| ML092540511 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 09/11/2009 |
| From: | Ajluni M Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-09-1411 | |
| Download: ML092540511 (18) | |
Text
Southern Nuclea~
Operating Company, InG
~,,t' September 11, 2009 Docket Nos.: 50-424 50-425 SOUTHERN'\\
COMPANY Ellcrgv fO.~<rl'C lOll)' Wo)'id NL-09-1411 U. S. Nuclear Regulato ATTN: Document Control Desk Washington, D. C. 205 ry Commission 55-0001 Vogtle Electric Generating Plant License Amendment Request to Revise Technical Specification (TS) Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Interim Alternate Repair Criteria Ladies and Gentlemen:
On May 19, 2009, Southern Nuclear Operating Company (SNC) submitted a license amendment request to revise Vogtle Electric Generating Plant (VEGP)
Technical Specification (TS) 5.5.9, "Steam Generator (SG) Program", and TS 5.6.10, "Steam Generator Tube Inspection Report." The proposed changes would revise the inspection scope and repair requirements of TS 5.5.9, "Steam Generator (SG) Program", and the reporting requirements of TS 5.6.10, "Steam Generator Tube Inspection Report." The proposed changes would establish a permanent alternate repair criterion to exclude portions of the tube below the top of the steam generator tube sheet from periodic steam generator tube inspections. Westinghouse WCAP-17071-P, Revision 0, "H*: Alternate Repair Criteria for the Tubesheet Expansion Region in Steam Generators with Hydraulically Expanded Tubes (Model F)," was submitted as enclosure 5 and provides the basis for the proposed change.
On July 10, 2009, SNC received a request for additional information (RAI) letter, which contained twenty-four (24) questions. As a result of a teleconference with NRC staff held on July 30, 2009, SNC received a second request for additional information letter on August 5, 2009. The August 5, 2009 letter contained three (3) questions related to questions 4, 20 and 24 from RAI letter received on July 10, 2009. The August 5, 2009 letter also contained one (1) additional question.
On August 28, 2009, SNC provided the responses to questions 1 through 24 of the July 10, 2009 letter and questions 1 through 4 of the August 5, 2009 letter.
On September 2, 2009, in a teleconference between NRC Staff and industry personnel, NRC Staff indicated that their concerns with eccentricity of the tube sheet tube bore in normal and accident conditions (RAI question 4 of the July 10, 2009 letter and RAI question 1 of the August 5, 1009 letter) have not been
U. S. Nuclear Regulatory Commission Log: NL-09-1411 Page 2 completely resolved to the satisfaction of the Staff. The Staff further indicated that there was insufficient time to resolve these issues to support approval of the permanent amendment request to support the fall 2009 refueling outage. As such, SNC is proposing to revise the proposed changes to the technical specification contained in May 18, 2009 letter to be a one-time change to TS 5.5.9 and TS 5.6.10 for Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle. SNC requests that the Staff provide the specific questions remaining to be resolved and that the review of the amendment request for permanent alternate repair criteria continues.
The permanent H* submittal is based on maintaining structural and leakage integrity in the event of an accident.
From a structural perspective, the 13.1 inch value of H* ensures that tube rupture or tube pull out from the tube sheet will not occur in the event of an accident in the entire life of the plant. Even in the event that all tubes in the steam generator have a 360 degree sever at 13.1 inches, structural integrity of the steam generator tube bundle will be maintained. This assumption bounds the current status of the Vogtle 1 and 2 steam generators with significant margin.
At Vogtle, tube flaw indications within the tube sheet have only been found at the hot leg tube ends and in bulges/overexpansions. Approximately 18,274 tube ends have been recently inspected at Vogtle. Twenty-seven flaw indications have been found in the inspections within 1 inch of the tube end. All of these indications were small and none met the tube repair criteria in the current technical specifications.
While flaws in bulges/overexpansions have been found at Vogtle 1, a separate inspection program for these indications has been implemented at both Vogtle 1 and 2. This inspection program is in accordance with VogUe's current technical specifications and industry guidance.
Based on these inspections, a limited number of flaws existed in the tube sheets of VogUe steam generators. The flaws that have been found are associated with residual stress conditions at either the tube ends or bulges/overexpansions within the tube sheet. No indications of a 360 degree sever has been detected in any steam generator at Vogtle. Consequently, the level of degradation in the Vogtle steam generators is very limited compared to the assumption of "all tubes severed" that was utilized in the development of the permanent H*.
Consequently, structural integrity will be assured for the operating period between inspections allowed by TS 5.5.9, "Steam Generator (SG) Program".
From a leakage perspective, projections of accident induced steam generator tube leakage are based on leakage rate factors applied to leakage detected during normal operation. The multiplication factor used for Vogtle bounds the expected increased leakage in the event of an accident at Vogtle.
U. S. Nuclear Regulatory Commission Log: NL-09-1411 Page 3 The projected accident induced leakage remains the same for both the single cycle and permanent H* amendments. No primary-to-secondary steam generator tube leakage has been detected during the current operating cycles at Vogtle.
For Vogtle, the number of tubes identified with flaws within the tUbesheet is small in comparison to the input assumptions used in the development of the permanent H*. Consequently, significant margin exists between the current state of the Vogtle steam generators and the conservative assumptions used as the basis for the permanent H*. Structural and leakage integrity will continue to be assured for the operating period between inspections allowed by TS 5.5.9, "Steam Generator (SG) Program" with the implementation of the proposed one time H*.
The requested changes do not expand the scope of the application as originally noticed, and does not impact the conclusions of the NRC staff's original proposed no significant hazards consideration determination as published in the Federal Register(74 FR 40240).
SNC requests approval of the proposed license amendments by September 18, 2009 to support the fall refueling outage for Vogtle Unit 1. The proposed changes would be implemented within 30 days of issuance of the amendment.
Mr. M. J. Ajluni states he is Nuclear Licensing Manager of Southern Nuclear Operating Company, is authorized to execute this oath on behalf of Southern Nuclear Operating Company and to the best of his knowledge and belief, the facts set forth in this letter are true.
The NRC commitments contained in this letter are provided as a table in. If you have any questions, please advise.
Respectfully submitted, SOUTHERN NUCLEAR OPERATING COMPANY
~~~
M. J. Ajluni Nuclear Licensing Manager
- g;;;::::;;;tbed before me this ~ day of~,2009.
Notary Public ~
My commission expires: 1-rJ/-/3..
MJAITAH/lac
U. S. Nuclear Regulatory Commission Log: NL-09-1411 Page 4
Enclosures:
- 1. Markup of Proposed Technical Specification
- 2. Typed Pages for Technical Specification
- 3. List of Regulatory Commitments cc:
Southern Nuclear Operating Company Mr. J. T. Gasser, Executive Vice President Mr. T. E. Tynan, Vice President - Vogtle Ms. P. M. Marino, Vice President - Engineering RType: CVC7000 U. S. Nuclear Regulatory Commission Mr. L. A. Reyes, Regional Administrator Ms. D. N. Wright, NRR Project Manager - Vogtle Mr. M. Cain, Senior Resident Inspector - Vogtle State of Georgia Mr. C. Clark, Commissioner - Department of Natural Resources
Vogtle Electric Generating Plant Units 1 and 2 Response to Request for Additional Information Related to license Amendment Request to Revise Technical Specification (TS)
Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Interim Alternate Repair Criteria Revised Markup of Proposed Technical Specification 5.5.9 and 5.6.10
5.5.9 Programs and Manuals 5.5 5.5 Programs and Manuals Steam Generator (SG) Program (continued)
- 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 per SG.
- 3. The operational LEAKAGE performance criterion is specified in LCO 3.4.13, "RCS Operational LEAKAGE."
- c.
Provisions for SG tube repair 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.
Insert 1
~ The following alternate tube repair criteria shall be applied as an
~rnative to the 40% depth based criteria:
Cor Unit 2 during Refueling Outage 11 and the subsequent operating cycle, degradation found in the portion of the tube below 17 inches fr-em the top of the hot leg tubeshoet does not require plugging.
f'or Unit 2 during Refueling Outag'3 11 and the subsequent operating cycle. degradation identified +n-t4e-portion of the tube from the top of the hot leg tubesheet to 17 inches below the top of the tubesheet shall Be-j:Hugged upon detection.
~Bf-I:JAA-1 during Refueling Outage 13 and the subsequent operating cycle. and for Unit 2 during Refuel ing Outage 12 and the subsequent operating cycle, degradation identified in the portion of the tube below
.+7 inches from the top of the hot IElg tubesheet does not require p~
For Unit 1 during Refueling OutagE) 13 and the subsequent operating cyc./. and for Unit 2 during Refueling Outage 12 and the subsequent operating cycle. degradation -k:leffiified in the por1ion of the tube from tI=te--kJp of the hot leg tubesheet-te--17 inches belm\\' the top of the hot leg tubesheet shall be plugged upon detection.
~-~ Unit 1 during Refueling OutagE! 14 and the SUbsequent operating cyelB and for Unit2 during Refueling Outage 13 and the subsequent operating cycle. tubes with flaws having a circumferential component 1ess-4l:l-aH-er equal40-*2Wdegrees found in the portion of the tube below 4-;l...if:t(,'-fle.& from the-top of the tubesheet and above 1 inch from the (continued)
Vogtle Units 1 and 2 5.5-8 Amendment No. ~ (Unit 1)
Amendment No. ~ (Unit 2)
5.5 5.5.9
- d.
Programs and Manuals 5.5 Programs and Manuals Steam Generator (SGl Program (continued)
~-fof~ttJBe.~tions. Periodic SG tube inspections shall be mflOO*.:r~-ffi!ffiBef-and portions4the tubes inspected and methods spection shall be performed with the objective of detecting flaws of any
-fe#. volumetFlc-flaws, axial and circumferential cracks) that may be em-aleB§--thB*IOB~-ef the tube.-from the tube to tubesheet weld at llite.ffilette--thB~IDe to tubesheet~ and that may fy-Ule applicable tube repair criteria, For Unit 2 during Refueling 1V\\::Ha1qe.-:tA-BfltHf1e-StIDsequent operating ~ the pOrtiOA of the tube Insert 2 bottom of the tubesheet do not require plugging. Tubes with fl3't~/s having a circumferential GBfRf}eBent greater than 203 degrees found in t-Ae-portion of the tube belm\\' 17 inches from the top of the tubesheet and above 1 inch from the bottom of the tubesheet shall be removed freH\\-se.p,t~
Tubes with service induced flaws located '/lithin the region from the top of-the tubesheet-te-17 inches below the top of the tubesheet-s4att-be re-moved from--s-ePv4Ge-cTubes wrth service indUBed--axial cracks found fB---.tAe portion of the tube-betew-+;'- inches from the top of the tubesheet do not require plugging,
'When more than one flaw '""ith circumferential components is found in the portion of the tube below 17 inches from the top of the tubesheet aflG above 1 inch from the bottom of the tubesheet with the total of the I;H:GtJmferential components greater than 203 degrees and an axial separation distance of less than 1 inch, then the tube shall be removed 1:rom service. When the circumferential components of each of the flaws are added. it is acceptable to count the overlapped portions only ImBO-in the total B-f-circumferential components, Whon one or more flaws with circumferential components are found in j he portion of-thBtube within 1 inc;.A-from the bottom of the tubesheet,
.IDE!- the total of the circumferential components found in the*ttille exceeds~then the tube shall be removed from service.
\\Nhen one or more flaws with circumferential components are found in the portion of-thBtube within 1 inch from the bottom of the tubesheet, iIDE!-w+tffin-l-ffi&l+axial separation distance of a flaw above~ inch from the bottom of the tubesheet, and the total of the circumferential components found in the tube exceeds 94 degrees. then the tube shall he-removed-fJ:em service. When the circumferential components of
~-fI.aw&are added. -it-+s-acceptable IDCount the overlapped portions only once in the total of circumferential components, (continued)
Vogtle Units 1 and 2 5.5-9 Amendment No. ~ (Unit 1)
Amendment No. ~ (Unit 2)
5.5.9 Programs and Manuals 5.5 5.5 Programs and Manuals Steam Generator (SG) Program (continued)
BeKm-l7-inches from the top of the hot leg tubesheet is excluded. For Y-n-i-1: 1 during Refueling Outage--+-d--afld the subsequent operating cycle, aOO-ffiF-Unit 2 during Refueling Outa~]e 12 and the subsequent operating e, the portion of the tube below-47 inches from the top of the hot leg e u e u es ee w IS no pa 0
e u e.
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. An assessment of degradation 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.
- 2.
Insert 3
- 3.
Inspect 100% of the tubes in each SG during the first refueling outage following SG replacement.
Inspect 100% of the tubes at sequential periods of 120,90, and, thereafter, 60 effective full power months. The first sequential period shall be considered to begin after the first inservice inspection of the SGs. In addition, inspect 50% of the tubes by the refueling outage nearest the midpoint of the period and the remaining 50% by the refueling outage nearest the end of the period. No SG shall operate for more than 48 effective full power months or two refueling outages (whichever is less) without being inspected.
Iy SG tube, then the next inspection for each SG for the degradation mechanism that caused the.BfaG-k indication shall not exceed 24-Bffective full power months or-GAe Fefueling outage (whichever-ifrfess). If definitive information. such as fr-Bffi examination of a pulled tube, diagnostic nondestructive testing, or e~f1eering evaluation indicates that a crack like indication is not associated with a crack(s), then the-indication need not be treated as a G~
- e.
Provisions for monitoring operational primary to secondary LEAKAGE.
5.5.10 Secondary Water Chemistry Program This program provides controls for monitoring secondary water chemistry to inhibit SG tube degradation. The program shall include:
(continued)
Vogtle Units 1 and 2 5.5-10 Amendment No. ~ (Unit 1)
Amendment No. ~ (Unit 2)
5.6 Reporting Requirements 5.6 Reporting Requirements 5.6.9 Deleted.
5.6.10 Steam Generator Tube Inspection Report A report shall be submitted within 180 days after the initial entry into MODE 4 following completion of an inspection performed in accordance with the Specification 5.5.9, Steam Generator (SG) Program. The report shall include:
- a.
The scope of inspections performed on each SG,
- b.
Active degradation mechanisms found,
- c.
Nondestructive examination techniques utilized for each degradation mechanism,
- d.
Location, orientation (if linear), and measured sizes (if available) of service induced indications,
- e.
Number of tubes plugged during the inspection outage for each active degradation mechanism, Insert 4
- f.
Total number and percentage of tubes "I.*
- g.
Ion monitoring, including the results of tube pulls and in-situ testing,
- h.
Follm'ling completion of a Unit-+inspection performed in Refueling Outage 44 (and any inspections performeG-in the subsequent operating cYGie+ and following completion of a Unit 2 inspection performed in Refueling Outage 4.J..{and any inspections performed in the subsequent operating cycle), the number of indications and location, size, orientation, whether initiated on primary-Gf secondary side for each service induced flaw IIvithin the thickness of the tubesheet. and the total of the circumferential components-aBG-aBy circumferential overla{3-below 17 inches from the top of the tubesheet as determined in accordance with TS 5.5.9.c.3;
- i.
Following completioA--e-f a Unit -+ffispection performed in Refueling Outage 14 (and any inspections performed in the subsequent operating cycle) and following completion-Bf-a Unit 2 inspection performed in Refueling Outage 13 (and any inspections performed in the subsequent operatirl§---cyGl+,-H'iBimH~afY--t&secondary LEAKAGE Fate-observed in each SG (if it is not practical-te-asslgnleakage to an individ-uat-SG, the entire primary--te secondary LEAKAGE should be conservatively assumed to be from one SG) during the
-iRs{:lection which 45-the sublect of
'-3-00
- j.
(continued)
Vogtle Units 1 and 2 5.6-6 Amendment No. ~(Unit 1)
Amendment No. ~(Unit 2)
Reporting Requirements 5.6 5.6 Reporting Requirements 5.6.10 Steam Generator Tube Inspection Report (continued)
Unit 2 inspection performed in Refueling Outage 13 (and any inspections performed In the subsequent operating cycT!et, -tI=I& calculated accident leakage rate from the portion of the tube below 17 inches from the~ of the tubesheet for the most limiting accident in the most limiting
~
Vogtle Units 1 and 2
~------------~--~-~--~-
Amendment No. 1-a2 (Unit-+)
Amendment No. 133 (Unit 2)
Insert 1:
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, tubes with service-induced flaws located greater than 13.1 inches below the top of the tubesheet do not require plugging. Tubes with service-induced flaws located in the portion of the tube from the top of the tubesheet to 13.1 inches below the top of the tubesheet shall be plugged upon detection.
Insert 2:
Provisions for 5G tube inspections. Periodic 5G 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 tube repair criteria. For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, portions of the tube below 13.1 inches below the top of the tubesheet are excluded from this requirement.
Insert 3:
If crack indications are found in portions of the 5G tube not excluded above, then the next inspection for each 5G for the degradation mechanism that caused the crack indication shall not exceed 24 effective full power months or one refueling outage (whichever is less). If definitive information, such as from examination of a pulled tube, diagnostic nondestructive 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.
Insert 4:
- h.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the primary to secondary LEAKAGE rate observed in each 5G (if it is not practical to assign the LEAKAGE to an individual 5G, the entire primary to secondary LEAKAGE should be conservatively assumed to be from one 5G) during the cycle preceding the inspection which is the subject of the report; and
- i.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the calculated accident induced leakage rate from the portion of the tubes below 13.1 inches from the top of the tubesheet for the most limiting accident in the most limiting 5G. In addition, if the calculated accident induced leakage rate from the most limiting accident is less than 2.48 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined.
- j.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the results of monitoring for tube axial displacement (slippage). If slippage is discovered, the implications of the discovery and corrective action shall be provided.
Vogtle Electric Generating Plant Units 1 and 2 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS)
Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Interim Alternate Repair Criteria Typed Pages for Technical Specification 5.5.9 and 5.6.10
5.5.9 Programs and Manuals 5.5 5.5 Programs and Manuals Steam Generator (SG) Program (continued)
- 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 per SG.
- 3. The operational LEAKAGE performance criterion is specified in LCO 3.4.13, "RCS Operational LEAKAGE."
- c.
Provisions for SG tube repair 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.
The following alternate tube repair criteria shall be applied as an alternative to the 40% depth based criteria:
For Unit 1 during Refueling Outage 15 and the SUbsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, tubes with service-induced flaws located greater than 13.1 inches below the top of the tubesheet do not require plugging.
Tubes with service-induced flaws located in the portion of the tube from the top of the tubesheet to 13.1 inches below the top of the tubesheet shall be plugged upon detection.
(continued)
Vogtle Units 1 and 2 5.5-8 Amendment No.
(Unit 1)
Amendment No.
(Unit 2)
5.5.9 Programs and Manuals 5.5 5.5 Programs and Manuals Steam Generator (SGl Program (continued)
- 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 tube repair criteria. For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, portions of the tube below 13.1 inches below the top of the tubesheet are excluded from this requirement.
(continued)
Vogtle Units 1 and 2 5.5-9 Amendment No.
(Unit 1)
Amendment No.
(Unit 2)
5.5 Programs and Manuals 5.5 Programs and Manuals 5.5.9 Steam Generator (SG) Program (continued)
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. An assessment of degradation 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.
- 2. Inspect 100% of the tubes at sequential periods of 120, 90, and, thereafter, 60 effective full power months. The first sequential period shall be considered to begin after the first inservice inspection of the SGs. In addition, inspect 50% of the tubes by the refueling outage nearest the midpoint of the period and the remaining 50% by the refueling outage nearest the end of the period. No SG shall operate for more than 48 effective full power months or two refueling outages (whichever is less) without being inspected.
- 3. If crack indications are found in portions of the SG tube not excluded above, then the next inspection for each SG for the degradation mechanism that caused the crack indication shall not exceed 24 effective full power months or one refueling outage (whichever is less).
If definitive information, such as from examination of a pulled tube, diagnostic nondestructive 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.
5.5.10 Secondarv Water Chemistrv Program This program provides controls for monitoring secondary water chemistry to inhibit SG tube degradation. The program shall include:
(continued)
Vogtle Units 1 and 2 5.5-10 Amendment No.
(Unit 1)
Amendment No.
(Unit 2)
Reporting Requirements 5.6 5.6 Reporting Requirements 5.6.9 Deleted.
5.6.10 Steam Generator Tube Inspection Report A report shall be submitted within 180 days after the initial entry into MODE 4 following completion of an inspection performed in accordance with the Specification 5.5.9, Steam Generator (SG) Program. The report shall include:
- a.
The scope of inspections performed on each SG,
- b.
Active degradation mechanisms found,
- c.
Nondestructive examination techniques utilized for each degradation mechanism,
- d.
Location, orientation (if linear), and measured sizes (if available) of service induced indications,
- e.
Number of tubes plugged during the inspection outage for each active degradation mechanism,
- f.
Total number and percentage of tubes plugged to date,
- g.
The results of condition monitoring, including the results of tube pulls and in-situ testing,
- h.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the primary to secondary LEAKAGE rate observed in each SG (if it is not practical to assign the LEAKAGE to an individual SG, the entire primary to secondary LEAKAGE should be conservatively assumed to be from one SG) during the cycle preceding the inspection which is the subject of the report; and
- i.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the calculated accident induced leakage rate from the portion of the tubes below 13.1 inches from the top of the tubesheet for the most limiting accident in the most limiting SG. In addition, if the calCUlated accident induced leakage rate from the most limiting accident is less than 2.48 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined.
- j.
For Unit 1 during Refueling Outage 15 and the subsequent operating cycle and for Unit 2 during Refueling Outage 14 and the subsequent operating cycle, the results of monitoring for tube axial displacement (slippage). If slippage is discovered, the implications of the discovery and corrective action shall be provided.
Vogtle Units 1 and 2 5.6-6 Amendment No.
(Unit 1)
Amendment No.
(Unit 2)
Vogtle Electric Generating Plant Units 1 and 2 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS)
Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Interim Alternate Repair Criteria List of Regulatory Commitments
List of Regulatory Commitments The following table identifies those actions committed by Southern Nuclear Operating Company in this document for Vogtle Electric Generating Plant. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.
Commitment Due Date/Event "SNC commits to revise the Steam Generator Program Strategic Plan procedure to include monitoring for tube slippage as part of the steam generator tube inspection program for Unit 1 and Unit 2. Slippage monitoring will occur for each inspection of the Vogtle 1 and 2 steam generators."
Prior to the start of Refueling Outage 1R15.
"SNC commits to perform a one time verification of the tube expansion to locate any significant deviations in the distance from the top of tubesheet to the bottom of the expansion transition (BET). If any significant deviations are found, the condition will be entered into the plant's corrective action program and dispositioned. Additionally, SNC commits to notify the NRC of significant deviations."
Prior to the startup following Refueling Outage 1R15 (Unit
- 1) and 2R14 (Unit 2).
"For the condition monitoring (CM) assessment, the At each scheduled component of operational leakage from the prior cycle from below the H* distance will be multiplied by a factor of 2.48 and added to the total accident leakage from any other source and compared to the allowable accident induced leakage limit. For inspection required by TS 5.5.9, "Steam Generator the operational assessment (OA), the difference in the leakage (SG) Program" between the allowable accident induced leakage and the beginning with 1R15 accident induced leakage from sources other than the (Unit 1) and 2R14 tubesheet expansion region will be divided by 2.48 and (Unit 2).
compared to the observed operational leakage. An administrative limit will be established to not exceed the calculated value."