ML110280056
| ML110280056 | |
| Person / Time | |
|---|---|
| Site: | Kewaunee  |
| Issue date: | 01/26/2011 |
| From: | Price J A Dominion Energy Kewaunee |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| 10-131A | |
| Download: ML110280056 (10) | |
Text
Dominion Energy Kewaunee, Inc.5000 Dominion Boulevard, GlenAllen, VA 23060 January 26, 2011 ATTN: Document Control Desk U.S.Nuclear Regulatory Commission Washington, DC 20555-0001 Serial NO.1 0-131A L1C/CDS/RO Docket No.: 50-305 License No.: DPR-43 DOMINION ENERGY KEWAUNEE, INC.KEWAUNEE POWER STATION RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION:
INSERVICE INSPECTION PROGRAM FOURTH TEN-YEAR INTERVAL 10 CFR 50.55a REQUEST NO.RR-2-2 On September 7, 2010, Dominion Energy Kewaunee, Inc.(DEK)submitted Relief Request RR-2-2 (Reference 1)for the Fourth Ten-year Interval of the Inservice Inspection Program for Kewaunee Power Station (KPS).The 10 CFR 50.55a request would establish alternate test requirements for the KPS large-bore hydraulic snubbers.Subsequently, the Nuclear Regulatory Commission (NRC)staff transmitted a request for additional information (RAI)regarding 10 CFR 50.55a Request RR-2-2 (reference 2).The RAI questions and associated DEK responses are provided in Attachment 1 to this letter.If you have questions orrequireadditional information, please feel free to contact Mr.Craig Sly at 804-273-2784.
Very truly yours, Serial No.10-131A 10 CFR 50.55a Request RR-2-2 Page 2 of 2
Attachment:
1.Response to Request for Additional Information:
Kewaunee Power Station Fourth Ten-year Interval Inservice Inspection Program 10 CFR 50.55a Request No.RR-2-2.
References:
1.Letter from J.Alan Price (Dominion Energy Kewaunee)to Document Control Desk,"Dominion Energy Kewaunee, Inc., Kewaunee Power Station, Inservice Inspection Program Fourth Ten-Year Interval, 10 CFR 50.55a Request No.RR-2-2," dated September 7, 2010.2.Email from Karl D.Feintuch (NRC)to Jack Gadzala (DEK)and Gurjendra Bedi (NRC),"ME4722 Request for Additional Information (RAI)," dated December 22, 2010.Commitments made by this letter: NONE cc: Regional Administrator, Region III U.S.Nuclear Regulatory Commission 2443 Warrenville Road Suite 210 Lisle, IL 60532-4352 Mr.Karl D.Feintuch Project Manager U.S.Nuclear Regulatory Commission One White Flint North, Mail Stop 08-H4A 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Kewaunee Power Station Serial No.1 0-131A ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION:
KEWAUNEE POWER STATION FOURTH TEN-YEAR INTERVAL INSERVICE INSPECTION PROGRAM 10 CFR 50.55a REQUEST NO.RR-2-2 KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.
Serial No.10-131A 10 CFR 50.55a Request RR-2-2 Page 1 of 7 Response to Request for Additional Information:
Fourth Ten-Year Intervallnservice Inspection Program 10 CFR 50.55a Request No.RR-2-2 By application dated September 7, 2010 (reference 1), Dominion Energy Kewaunee, Inc.(DEK)submitted Relief Request RR-2-2 for the Fourth Ten-year Interval of the Inservice Inspection Program for Kewaunee Power Station (KPS).The 10 CFR 50.55a request would establish alternate test requirements for the KPS large-bore hydraulic snubbers.Subsequently, the Nuclear Regulatory Commission (NRC)staff transmitted a request for additional information (RAI)regarding 10 CFR 50.55a Request RR-2-2 (reference 2).The RAI questions and associated DEK responses are provided below.NRC Question 1 In Section 4,"Reason for Request, Background," the first paragraph states, in part, that"The KPS lSI Fourth 10-Year Inspection IntelVal, Appendix F,"Augmented Examination Programs", Section 2.f, requires all safety related hydraulic shock suppressors be visually examined and tested in accordance with KPS Technical Specification (TS)Section 4.14,"Testing and SUlVeillance of Shock Suppressors (Snubbers)"." The applicable American Society of Mechanical Engineers (ASME)Section XI Code for KPS is the 1998 Edition with the 2000 Addenda.ASME Section XI, Article IWF-5000 specifies the requirements for inselVice examination and testing of snubbers.(a)Did the NRC ever authorize KPS to use the TS Section 4.14 in lieu of the ASME Section XI Code requirements of IWF-5000 for lSI and testing of safety related hydraulic shock suppressors?
If so, please provide information regarding this authorization from the NRC.(b)During a teleconference regarding the Kewaunee Improved TS conversion, on April 1, 2010, Dominion Energy Kewaunee (DEK)informed the NRC staff that KPS was converting its snubbers program from the TS to the ASME OM Code Subsection ISTD.However, in this relief request, DEK states that applicable Code requirements for the snubber lSI and testing program are as specified in IWF-5000 of the ASME Code Section XI.Please provide details regarding which ASME Code is being used for lSI and testing of snubbers at KPS.
Serial No.10-131A 10 CFR 50.55a Request RR-2-2 Page 2 of 7 Response: (a)The NRC issued Amendment 14 to the KPS Operating License on March 1, 1977.This Amendment included creation of new TS Section 4.14,"Testing and Surveillance of Shock Suppressors (Snubbers)." TS 4.14 included an allowance regarding SG snubbers that stated;"The Anchor Holth suppressors used on the steam generators are exempt from functional testing requirements." This exemption was provided due to the impracticality of functionally testing these suppressors.
The NRC's accompanying safety evaluation (SE)stated, in part, the following:
Because of the continued incidence of snubber failures, we have concluded that snubber operability and surveillance requirements should be incorporated into the Technical Specifications.
An inspection program is specified to provide additional assurance that the snubbers remain operable.The inspection frequency is based upon maintaining a constant level of snubber protection.
To further increase the level of snubber reliability, the Technical Specifications require functional tests.The tests will verify proper piston movement, lockup and bleed.We have concluded that the proposed additions to the Technical Specifications, as modified, increase the probability of successful snubber performance, increase reactor safety and we therefore find them acceptable.
The NRC SE contained no discussion of ASME Section XI Code requirements of IWF-5000 for lSI and testing of safety related hydraulic shock suppressors.
As discussed in Section 4 of the Relief Request (reference 1), the current large-bore hydraulic snubber testing program was developed based on discussions in 1987 between the previous license holder for KPS and the NRC staff during a meeting associated with IE Bulletin 79-14,"Seismic Analyses for As-Built Safety Related Piping Systems".Although TS 4.14 states that the large-bore SG snubbers are exempt from functional testing requirements, the previous license holder for KPS nonetheless agreed to include them in the Snubber Test Program.However, the large-bore SG snubbers were not grouped with other (small-bore) hydraulic snubbers and were provided with a long testing interval.(b)The conversion from Custom TS (CTS)to Improved TS (ITS)includes relocating TS snubber surveillance testing requirements from CTS 4.14 to the Technical Requirements Manual (TRM).As part of ITS implementation, the TRM requirements will become effective and will require inservice inspections of snubbers in accordance with the Snubber Test Program.The Snubber Test Program implements the ASME OM Code and ASME Section XI, 1998 Edition through the 2000 Addenda, as required by CTS 4.2,"ASME Code Class In-Service Inspection and Testing." The code of record endorses IWF-5000.IWF endorses OM-4 for inspection and testing of snubbers.KPS currently uses OM-4 for inspection and Serial No.1 0-131A 10 CFR 50.55a Request RR-2-2 Page 3 of 7 testing of snubbers.However, DEK plans to revise the Snubber Test Program to use ASME OM Code Subsection ISTD during the next 1 O-year interval.NRC Question 2 In Section 4, the last paragraph on Page 2 of 6, states, in part, that"Under the currently applicable versions of the ASMEIOM codes, the steam generator (SG)large-bore hydraulic snubbers are considered to be within the same grouping (or population) as other plant hydraulic snubbers." Please confirm that there are no mechanical snubbers installed at KPS.Response: There are no mechanical snubbers installed at KPS.All snubbers are hydraulic.
NRC Question 3 In Section 5,"Proposed Alternative and Basis for Use," Subsection 5.b states, in part that"functional testing be petformed once for SG1A Large-Bore 900 KIP Hydraulic Snubber (RC-H86)and once for SG1B Large-Bore 900 KIP Hydraulic SnubberH87)during the Fourth Ten-Year Interval." Please explain how testing large-bore snubbers, RC-H86 or RC-H87, only once per the Fourth Ten-Year Interval will meet the current snubber testing requirements at KPS or explain the basis for only testing once per ten-year Interval.Response: Testing of snubbers was required by CTS 4.2,"ASME Code Class In-Service Inspection and Testing," which endorses the ASME Code.CTS 4.2 states that testing and surveillance of snubbers is specified in CTS 4.14,"Testing and Surveillance of Shock Suppressors (Snubbers)." CTS 4.14 exempts the Anker Holth snubbers from functional testing requirements.
These CTS requirements will be relocated to the TRM as part of the conversion to ITS.The Anker Holth large-bore snubbers are included in the lSI Program, with inspection and testing in accordance with the lSI Program.Surveillance Procedure SP-55-313,"Steam Generator Hydraulic Snubber Testing," implements the inspection and testing requirements.
The safety-related small-bore snubber population is divided into 9 groups.Testing of one of the nine groups every 18 months meets the 10%sampling plan specified in the Snubber Test Program.The two large-bore snubbers were not included in these groups because they are exempt from functional testing per TS.Since one snubber group is tested at each 18-month interval, the Snubber Test Program would allow up to 13.5 years between tests of individual small-bore snubbers.Had the two large-bore Serial No.10-131A 10 CFR 50.55a Request RR-2-2 Page 4 of 7 snubbers been included in this sampling plan, the number of groups would still have been nine and the time between tests would still have been as high as 13.5 years.Therefore, testing large-bore snubbers, RC-H86 or RC-H87, once per the FourthYear Interval will meet the current snubber testing requirements at KPS because the proposed test interval is bounded by the 13.5-year interval currently allowed by the Snubber Test Program.NRC Question 4 In Section 5, under the"Bases for Use" subsection, DEK provides a history of functional testing of SG large-bore hydraulic snubbers at Kewanee.Please provide the results of the functional testing performed during all the refueling outages from 1996 through 2009.Response: The results of the functional testing of SG large-bore hydraulic snubbers RC-H86 and RC-H87 for all refueling outages from 1996 through 2009 revealed no functional testing failures or visual failures.The specific results were as follows.a.1996 refueling outage: The Steam Generator 1A Large-Bore Hydraulic Snubber was functionally tested with successful results.C't.t A C T SG1A enslon ompresslon ccep'ance rr erra Drag Breakaway 15241bs 1143 Ibs<20,000 Ibs Drag Load/Binding 3955 Ibs 4010lbs<20,000 Ibs Functional Lockup0.971PM0.831PM 0.6-10.0 IPM Functional Bleed Rate 0.11261PM 0.11751PM 0.1-0.45 IPM Functional Load 500 kips 500 kips 500-505 kips b.1998 refueling outage: The Steam Generator1B Large-Bore Hydraulic Snubber was functionally tested with successful results.C't.tA C T SG1B enslon ompresslon ccep1ance rr erra Drag Breakaway 1721 Ibs 16281bs<20,000 Ibs Drag Load/Binding45581bs41861bs
<20,000 Ibs Functional Lockup 1.081PM 0.961PM 0.6-10.0 IPM Functional Bleed Rate 0.13151PM 0.12281PM 0.1-0.45 IPM Functional Load 501 kips 501 kips 500-505 kips Serial NO.1 0-131A 10 CFR 50.55a Request RR-2-2 Page 5 of 7 c.2001 refueling outage: Both Steam Generator 1A and Steam Generator1BBore HydraulicSnubberswere removed, functionally tested, disassembled, inspected, rebuilt, reassembled and functionally tested with successful results.t A C T.t b'Id SG 1A f d as oun-pnor 0 re UI enslon ompresslon ccep'ance ntena Drag Breakaway<2.0 kips<2.0 kips<20 kips Drag Load/Binding
<2.0 kips<2.0 kips<20 kips Functional Lockup 1.041PM 0.881PM 0.6-10.0 IPM Functional Bleed Rate 0.10991PM 0.11161PM 0.1-0.45 IPM Functional Load 503 kips 504 kips 500-505 kips C'A C.tb'Id T SG 1B f d as oun-pnor 0 re UI ens Ion ompresslon cceptance ntena Drag Breakaway<2.0 kips<2.0 kips<20 kips Drag Load/Binding
<2.0 kips<2.0 kips<20 kips Functional Lockup 0.951PM 0.931PM 0.6-10.0 IPM Functional Bleed Rate 0.12771PM 0.12171PM 0.1-0.45 IPM Functional Load 502 kips 503 kips 500-505 kips t A C T b'Id SG 1A Iftft ase-a er re UI enslon ompresslon ccep1ance ntena Drag Breakaway<2.0 kips<2.5 kips<20 kips Drag Load/Binding
<2.0 kips<2.5 kips<20 kips Functional Lockup 1.071PM 0.871PM 0.6-10.0 IPM Functional Bleed Rate 0.10791PM 0.10841PM 0.1-0.45 IPM Functional Load 504 kips 503 kips 500-505 kips C't.t A C T b'Id SG1BIftft as e-a er re UI enslon ompresslon ccep'ance n ena Drag Breakaway<2.5 kips<2.5 kips<20 kips Drag Load/Binding
<2.5 kips<2.5 kips<20 kips Functional Lockup 0.991PM 0.881PM 0.6-10.0 IPM Functional Bleed Rate 0.12701PM 0.11971PM 0.1-0.45 IPM Functional Load 501 kips 502 kips 500-505 kips d.2008 refueling outage: The Steam Generator 1A Large-Bore Hydraulic Snubber was functionally tested with successful results.C't.t A C T SG1A enslon ompresslon cceplance n ena Drag Breakaway 3.0 kips<1 kips<20 kips Drag Load/Binding 3.5 kips 1 kips<20 kips Functional Lockup 0.81 IPM 0.831PM 0.6-10.0 IPM Functional Bleed Rate 0.1201PM 0.1261PM 0.1-0.45 IPM Functional Load 502 kips 502 kips 500-505 kips Serial No.10-131A 10 CFR 50.55a Request RR-2-2 Page 6 of 7 e.2009 refueling outage: The Steam Generator1B Large-Bore Hydraulic Snubber was functionally tested with successful results.C't.t A C T SG1B enslon ompresslon ccep 1 ance n ena Drag Breakaway 6 kips 8 kips<20 kips Drag Load/Binding 6 kips 6 kips<20 kips Functional Lockup 0.651PM 0.681PM 0.6-10.0 IPM Functional Bleed Rate 0.1361PM 0.1311PM 0.1-0.45 IPM Functional Load 503 kips 503 kips 500-505 kips NRC Question 5 The TS Section 4.14 does not address the requirements of OM-4, Section 2.3.2 and Section 3.2.4 related to inservice examination and functional testing of snubbers, specifically Section 2.3.4.3,"Examination Failure Mode Groups," and Section 3.2.4.2,"Test Failure Mode Groups." Please explain how the KPS snubber program meets the requirements of ASME OM-4, Sections 2.3.4.3 and 3.2.4.2.Response: As discussed in the response to Question 3 above, testing of snubbers was required by CTS 4.2,"ASME Code Class In-Service Inspection and Testing," which endorses the ASME Code.CTS 4.2 states that testing and surveillance of snubbers is specified in CTS 4.14,"Testing and Surveillance of Shock Suppressors (Snubbers)." The conversion from CTS to ITS includes relocating snubber surveillance testing requirements from CTS 4.14 to the TRM.The TRM will require performance of snubber inservice inspections in accordance with the Snubber Test Program.The KPS Snubber Test Program specifically requires that snubbers be inspected and tested per the requirements of ASME OM-4 (which includes the requirements of Sections 2.3.4.3 and 3.2.4.2).As stated in the ITS submittal to NRC, the requirement to perform snubber inspections is specified in 10 CFR 50.55a and the requirement to perform snubber inspections and testing is specified in ASME Section XI, as modified by approved relief requests.Additionally, these requirements are controlled by the lSI Program which is required by 10 CFR 50.55a.Compliance with 10 CFR 50.55a is required by the KPS Operating License.
Serial NO.1 0-131A 10 CFR 50.55a Request RR-2-2 Page 7 of 7 References 1.Letter from J.Alan Price (Dominion Energy Kewaunee)to Document Control Desk,"Dominion Energy Kewaunee, Inc., Kewaunee Power Station, Inservice Inspection Program Fourth Ten-Year Interval, 10 CFR 50.55a Request No.RR-2-2," dated September 7, 2010.2.Email from Karl D.Feintuch (NRC)to Jack Gadzala (DEK)and Gurjendra Bedi (NRC),"ME4722 Request for Additional Information (RAI)," dated December 22, 2010.