ML061010660
| ML061010660 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 04/11/2006 |
| From: | Marinos E Plant Licensing Branch III-2 |
| To: | Christian D Virginia Electric & Power Co (VEPCO) |
| s dawson, 415-1485 | |
| References | |
| TAC MC6663, TAC MC6664, TAC MC6665, TAC MC6666 | |
| Download: ML061010660 (12) | |
Text
April 11, 2006 Mr. David A. Christian Senior Vice President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
NORTH ANNA POWER STATION, UNIT NOS. 1 AND 2 (NORTH ANNA 1 AND 2) - RELIEF REQUESTS P-3 AND P-4 (TAC NOS. MC6663, MC6664, MC6665, AND MC6666)
Dear Mr. Christian:
By letter dated April 11, 2005, Virginia Electric and Power Company (VEPCO) requested relief from the American Society of Mechanical Engineers, Operation and Maintenance of Nuclear Power Plants (ASME OM Code), requirements for the third 10-year inservice testing (IST) program interval at North Anna 1 and 2. In its submittal, VEPCO requested Nuclear Regulatory Commission (NRC) staff approval of Relief Requests P-3 and P-4.
Our evaluations of Relief Requests P-3 and P-4 for North Anna 1 and 2 are enclosed. The NRC staff has determined that VEPCOs proposed alternative provides an acceptable level of quality and safety. Therefore, VEPCOs Relief Requests P-3 and P-4 are authorized pursuant to Title 10 of the Code of Federal Regulations, Section 50.55a(a)(3)(i), for the third 10-year IST intervals at North Anna 1 and 2.
Sincerely,
/RA/
Evangelos C. Marinos, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339
Enclosure:
Safety Evaluation cc w/encl: See next page
April 11, 2006 Mr. David A. Christian Senior Vice President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
NORTH ANNA POWER STATION, UNIT NOS. 1 AND 2 (NORTH ANNA 1 AND 2) - RELIEF REQUESTS P-3 AND P-4 (TAC NOS. MC6663, MC6664, MC6665, AND MC6666)
Dear Mr. Christian:
By letter dated April 11, 2005, Virginia Electric and Power Company (VEPCO) requested relief from the American Society of Mechanical Engineers, Operation and Maintenance of Nuclear Power Plants (ASME OM Code), requirements for the third 10-year inservice testing (IST) program interval at North Anna 1 and 2. In its submittal, VEPCO requested Nuclear Regulatory Commission (NRC) staff approval of Relief Requests P-3 and P-4.
Our evaluations of Relief Requests P-3 and P-4 for North Anna 1 and 2 are enclosed. The NRC staff has determined that VEPCOs proposed alternative provides an acceptable level of quality and safety. Therefore, VEPCOs Relief Requests P-3 and P-4 are authorized pursuant to Title 10 of the Code of Federal Regulations, Section 50.55a(a)(3)(i), for the third 10-year IST intervals at North Anna 1 and 2.
Sincerely,
/RA/
Evangelos C. Marinos, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339
Enclosure:
Safety Evaluation cc w/encl: See next page Distribution: RidsAcrsAcnwMailCenter RidsRgn2MailCenter(KLandis)
PUBLIC RidsNrrPMSMonarque RidsNrrCptb(SSlee)
LPL2-1 Rdg. RidsNrrLAMOBrien RidsNrrCptb(GBedi)
RidsOgcRp RidsNrrLplc(EMarinos) SLee, EDO RII BSingal, DORL DPR
- Date of SE input ADAMS ACCESSION NO.:ML061010660 NRR-028 OFFICE NRR/LPL2-1/PM NRR/LPL2-1/LA NRR/CPTB/BC OGC NRR/LPL2-1/BC NAME SMonarque:srm MOBrien SSLee* M Woods EMarinos DATE 4/5/2006 4/11/06 02/14/2006 4/5/06 4/11/06
OFFICIAL RECORD COPY SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUESTS P-3 AND P-4 NORTH ANNA POWER STATION, UNIT NOS. 1 AND 2 VIRGINIA ELECTRIC AND POWER COMPANY DOCKET NOS. 50-338 AND 50-339
1.0 INTRODUCTION
By letter dated April 11, 2005, Virginia Electric and Power Company (the licensee) submitted Relief Requests P-3 and P-4 for the third 10-year inservice testing (IST) program intervals at North Anna Power Station, Unit Nos. 1 and 2 (North Anna 1 and 2). In Relief Requests P-3 and P-4, the licensee proposed alternatives to the requirements of the American Society of Mechanical Engineers (ASME), Code for Operation and Maintenance of Nuclear Power Plants (OM Code), for the North Anna 1 and 2. The Nuclear Regulatory Commission (NRC) staffs evaluation of Relief Requests P-3 and P-4 are contained herein. These relief requests are applicable to the third 10-year interval IST program at North Anna 1 and 2, which commenced on December 15, 2001.
2.0 REGULATORY EVALUATION
Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 50.55a requires that IST of certain ASME Code Class 1, 2, and 3 pumps and valves be performed in accordance with the ASME OM Code and applicable addenda, except where alternatives have been authorized or relief has been requested by the licensee and granted by the Commission pursuant to Sections (a)(3)(i), (a)(3)(ii), or (f)(6)(i) of 10 CFR 50.55a.
In accordance with 10 CFR 50.55a(f)(4)(ii), licensees are required to comply with the requirements of the latest edition and addenda of the ASME Code incorporated by reference in the regulations 12 months prior to the start of subsequent 120-month IST program intervals.
In proposing alternatives or requesting relief, the licensee must demonstrate that (1) the proposed alternatives provide an acceptable level of quality and safety; (2) compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety; or (3) conformance is impractical for the facility. Section 50.55a authorizes the Commission to approve alternatives and to grant relief from ASME Code requirements upon making necessary findings. NRC guidance contained in Generic Letter (GL) 89-04, Guidance on Developing Acceptable Inservice Testing Programs, provides alternatives to Code requirements which are acceptable. Further guidance is given in GL 89-04, Supplement 1, and NUREG-1482, Guidance for Inservice Testing at Nuclear Power Plants.
By letter dated April 11, 2005, the licensee, submitted Relief Requests P-3 and P-4 for its third 10-year IST program interval at North Anna 1 and 2, which commenced on December 15, 2001.
In Relief Requests P-3 and P-4, the licensee proposed alternatives to the requirements of the
ASME OM Code for North Anna 1 and 2. The third 10-year IST program was developed to meet the requirements of the 1995 edition through 1996 addenda of the ASME OM Code pursuant to 10 CFR 50.55a(f)(4)(ii).
The NRC staffs evaluations of Relief Requests P-3 and P-4 are given below.
3.0 TECHNICAL EVALUATION
3.1 Pump Relief Requests P-3 3.1.1 Code Requirements Paragraph ISTB 5.2.1, Group A Test, states Group A test shall be conducted with the pump operating at a specified reference point.
Paragraph ISTB 5.2.3, Comprehensive Test, states Comprehensive test shall be conducted with the pump operating at a specified reference point.
3.1.2 Specific Relief Requested The licensee requests relief from the ASME OM Code requirements of paragraphs ISTB 5.2.1 and ISTB 5.2.3 for service water (SW) pumps 1-SW-P-1A, 1-SW-P-1B, 2-SW-P-1A, and 2-SW-P-1B.
3.1.3 Component Identification The components affected by this relief request are SW pumps 1-SW-P-1A and 1-SW-P-1B for North Anna 1, and 2-SW-P-1A and 2-SW-P-1B for North Anna 2. These pumps are classified as ASME Class 3, Group A pumps.
The SW pumps supply cooling water to the component cooling (CC) and recirculation spray heat exchangers as well as other safety-related components.
3.1.4 Licensees Basis for Requesting Relief Plant conditions may not be the same as when the reference values were established. Many reference points must be established to anticipate future conditions. In the service water system, reproducing one of these reference flow points is not practical with the large butterfly valves installed, and it may not be desirable to alter cooling because of other plant operating parameters.
Therefore, the pumps will be tested over a range of flows, and the results will be compared to the acceptance criteria based on a portion of the pump curve and the hydraulic acceptance criteria given in ISTB.
The guidelines set forth in Code Case OMN-9, Use of a Pump Curve for Testing, and conditions identified in Regulatory Guide [RG] 1.192, []Operation and Maintenance Code Case Acceptability, ASME OM Code[], will be followed.
The conditions identified in RG 1.192 are:
(1) When a reference curve may have been affected by repair, replacement, or routine servicing of a pump, a new reference curve must be determined, or an existing reference curve must be reconfirmed, in accordance with Section 3 of this Code Case.
(2) If it is necessary or desirable, for some reason other than stated in Section 4 of this Code Case, to establish an additional reference curve or set of curves, these new curves must be determined in accordance with Section 3.
Past vibration data for the subject pumps have been reviewed, and it has been determined that pump vibration does not vary significantly with flow rate over the range of test flow rates. The [proposed] alternative testing requirement provides an acceptable level of quality and safety.
3.1.5 Licensees Proposed Alternative Testing The licensee requests to use the alternative testing (established reference curves) guidelines set forth in Code Case OMN-9, Use of a Pump Curve for Testing, and conditions identified in RG 1.192, in lieu of the ASME OM Code paragraphs ISTB 5.2.1 and ISTB 5.2.3 requirements for SW pumps 1-SW-P-1A, 1-SW-P-1B, 2-SW-P-1A, and 2-SW-P-1B.
The third 10-year IST interval at North Anna 1 and 2 is based on ASME OM Code, 1995 edition through 1996 addenda. However, since Code Case OMN-9 is only applicable to ASME OM Code 1990 through the OMb 1992 addenda, relief is required to implement Code Case OMN-9.
The use of Code Case OMN-9 is acceptable with certain conditions as identified by the NRC staff in RG 1.192.
Acceptance criteria will be based on a portion of the pump curves and not on discreet reference values. The testing guidelines set forth in Code Case OMN-9 and the conditions identified in RG 1.192 will be followed.
3.1.6 NRC Staffs Evaluation of Pump Relief Requests P-3 ASME OM Code, paragraphs ISTB 5.2.1 and ISTB 5.2.3 require that Group A and Comprehensive tests be conducted with the pump operating at a specified reference point.
The licensee states that plant conditions may not be the same as when the reference values were established and reference points must be established to anticipate future conditions. In the SW system, reproducing one of these reference flow points is not practical. The SW pumps operate under a variety of flow rate and differential pressure conditions. Varying the flow rate of these pumps is impractical during normal plant operating conditions because of the potential loss of adequate flow to heat exchangers and the potential of creating plant transients.
Therefore, the SW pumps will be tested over a range of flows, and results will be compared to
acceptance criteria based on a portion of the pump curve and the hydraulic acceptance criteria given in OM Code Subsection ISTB.
As discussed in NUREG-1482, Guidance for Inservice Testing at Nuclear Power Plants, Section 5.2, the use of pump curves for reference values of flow rate and differential pressure is acceptable when it is impractical to establish a fixed set of reference values. Pump curves represent a set of infinite reference points of flow rate and differential pressure. Establishing a reference curve for the pump when it is known to be operating acceptably and basing the acceptance criteria on this curve can permit evaluation of pump condition and detection of degradation. However, because of a greater potential for error associated with the use of pump curves, Section 5.2 of NUREG-1482 delineates seven elements on the procedures for developing and implementing the curves that should be incorporated into the IST program.
These elements are included in Code Case OMN-9. Because Code Case OMN-9 is applicable to OM Code 1990 through OMb Code 1992, relief is required to implement Code Case OMN-9 with the 1995 edition through 1996 addenda of the OM Code.
The latest NRC staff guidance is described in NUREG-1482, Revision 1, which is developed based on the ASME OM Code, 1995 edition through 2000 addenda. NUREG-1482, Revision 1, Section 5.2 allows the use of Code Case OMN-9, Revision 0. The licensees proposed use of established reference curves as specified in Code Case OMN-9, Use of a Pump Curve for Testing, is consistent with the guidelines in Section 5.2 of NUREG-1482 and provides reasonable assurance of the operational readiness of the SW pumps. RG 1.192, Operation and Maintenance Code Case Acceptability, ASME Code Case, lists the OM Code Cases that the NRC staff finds acceptable for licensees to implement in their IST program. In particular, the NRC staff accepted Code Case OMN-9, with the conditions identified in RG 1.192. The NRC staff considers the provision in Code Case OMN-9 to be acceptable for establishing reference curves for comprehensive and quarterly pump testing and for determining the applicable alert and action range. On the basis that the licensee will develop new pump curves in accordance with Code Case OMN-9 and will follow the conditions identified in RG 1.192, the NRC staff finds that the proposed alternative provides an acceptable level of quality and safety.
3.1.7 Conclusion The licensees proposed alternative to establish reference pump curves as specified in Code Case OMN-9, and to follow the conditions identified in RG 1.192 for the SW pumps is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that the alternative provides an acceptable level of quality and safety. This alternative is authorized for the third 10-year IST intervals at North Anna 1 and 2.
3.2 Pump Relief Requests P-4 3.2.1 Code Requirements Paragraph ISTB 5.2.1, Group A Test, states Group A test shall be conducted with the pump operating at a specified reference point.
Paragraph ISTB 5.2.3, Comprehensive Test, states Comprehensive test shall be conducted with the pump operating at a specified reference point.
3.2.2 Specific Relief Requested The licensee requests relief from the ASME OM Code requirements of paragraphs ISTB 5.2.1 and ISTB 5.2.3 for CC pumps 1-CC-P-1A, 1-CC-P-1B, and 2-CC-P-1A, and 2-CC-P-1B.
3.2.3 Component Identification The component affected by these relief requests are CC pumps 1-CC-P-1A and 1-CC-P-1B at North Anna 1, and 2-CC-P-1A and 2-CC-P-1B at North Anna 2. These pumps are classified as ASME Class 3, Group A pumps.
The CC pumps supply cooling water to the CC heat exchangers, which remove heat from systems containing radioactive fluids.
3.2.4 Licensees Basis for Requesting Relief Plant conditions may not be the same as when the reference values were established. Many reference points must be established to anticipate future conditions. In the [CC] system, reproducing one of these references flow points is difficult with the large butterfly valves installed, and it may be desirable to alter cooling because of other plant operating parameters. Therefore, the pumps will be tested over a range of flows, and the results will be compared to acceptance criteria based on a portion of the pump curve and the hydraulic acceptance criteria given in ISTB.
The guidelines set forth in Code Case OMN-9, Use of a Pump Curve for Testing, and conditions identified in [RG] 1.192, Operation and Maintenance Code Case Acceptability, ASME OM Code, will be followed. The conditions identified in RG 1.192 are:
(1) When a reference curve may have been affected by repair, replacement, or routine servicing of a pump, a new reference curve must be determined, or an existing reference curve must be reconfirmed, in accordance with Section 3 of this Code Case.
(2) If it is necessary or desirable, for some reason other than stated in Section 4 of this Code Case, to established an additional reference curve or set of curves, these new curves must be determined in accordance with Section 3 of the Code Case.
Past vibration data for the subject pumps have been reviewed, and it has been determined that pump vibration does not vary significantly with flow rate over the range of test flow rates. The alternative testing requirements of ISTB 5.2.1 and ISTB 5.2.3 provides an acceptable level of quality and safety.
3.2.5 Licensees Proposed Alternative Testing The licensee requests to use the alternative testing (established reference curves) guidelines set forth in Code Case OMN-9, and conditions identified in RG 1.192, in lieu of the ASME OM
Code paragraphs ISTB 5.2.1 and ISTB 5.2.3 for requirements for CC pumps 1-CC-P-1A, 1-CC-P-1B, and 2-CC-P-1A, and 2-CC-P-1B.
The third 10-year IST interval at North Anna 1 and 2 is based on ASME OM Code, 1995 edition through 1996 addenda. However, since Code Case OMN-9 is only applicable to ASME OM Code 1990 through the OMb 1992 addenda, relief is required to implement Code Case OMN-9.
The use of Code Case OMN-9 is acceptable with certain conditions as identified by the NRC staff in RG 1.192.
Acceptance criteria will be based on a portion of the pump curves and not on discreet reference values. The testing guidelines set forth in Code Case OMN-9 and the conditions identified in RG 1.192 will be followed.
3.2.6 NRC Staffs Evaluation of Pump Relief Requests P-4 ASME OM Code, paragraphs ISTB 5.2.1 and ISTB 5.2.3 require that Group A and Comprehensive tests be conducted with the pump operating at a specified reference point.
The licensee states that plant conditions may not be the same as when the reference values were established and reference points must be established to anticipate future conditions. In the CC system, reproducing one of these reference flow points is not practical. The CC water pumps operate under a variety of flow rate and differential pressure conditions. Varying the flow rate of these pumps is impractical during normal plant operating conditions because of the potential loss of adequate flow to heat exchangers and the potential of creating plant transients.
Therefore, the CC water pumps will be tested over a range of flows, and results will be compared to acceptance criteria based on a portion of the pump curve and the hydraulic acceptance criteria given in OM Code Subsection ISTB.
As discussed in NUREG-1482, Section 5.2, the use of pump curves for reference values of flow rate and differential pressure is acceptable when it is impractical to establish a fixed set of reference values. Pump curves represent a set of infinite reference points of flow rate and differential pressure. Establishing a reference curve for the pump when it is known to be operating acceptably and basing the acceptance criteria on this curve can permit evaluation of pump condition and detection of degradation. However, because of a greater potential for error associated with the use of pump curves, Section 5.2 of NUREG-1482 delineates seven elements on the procedures for developing and implementing the curves that should be incorporated into the IST program. These elements are included in Code Case OMN-9.
Because Code Case OMN-9 is applicable to OM Code 1990 through OMb Code 1992, relief is required to implement Code Case OMN-9 with 1995 edition through 1996 addenda of the OM Code.
The latest NRC staff guidance is described in NUREG-1482, Revision 1, which is developed based on the ASME OM Code, 1995 edition through 2000 addenda. NUREG-1482, Revision 1, Section 5.2 allows the use of Code Case OMN-9, Revision 0. The licensee proposed use of established reference curves as specified in Code Case OMN-9, is consistent with the guidelines in Section 5.2 of NUREG-1482 and provides reasonable assurance of the operational readiness of the CC water pumps. RG 1.192, lists the OM Code Cases that the NRC staff finds acceptable for licensees to implement in their IST program. In particular,
the NRC staff accepted Code Case OMN-9, with conditions identified in RG 1.192. The NRC staff considers the provision in Code Case OMN-9 to be acceptable for establishing reference curves for comprehensive and quarterly pump testing and for determining the applicable alert and action range. On the basis that the licensee will develop new pump curves in accordance with Code Case OMN-9 and will follow the conditions identified in RG 1.192, the NRC staff finds that the proposed alternative provides an acceptable level of quality and safety.
3.2.7 Conclusion The licensees proposed alternative to establish reference pump curves as specified in Code Case OMN-9, and the conditions identified in RG 1.192 for the CC water pumps is authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that the alternative provides an acceptable level of quality and safety. This alternative is authorized for the third 10-year IST intervals at North Anna 1 and 2.
4.0 CONCLUSION
S The Relief Requests P-3 and P-4 for North Anna 1 and 2 are authorized pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that the proposed alternatives provide an acceptable level of quality and safety. These alternatives are authorized for the third 10-year IST intervals at North Anna 1 and 2.
5.0 REFERENCES
U.S. Code of Federal Regulations, Domestic Licensing of Production and Utilization Facilities, Part 50, Chapter I, Title 10, Energy, Section 50.55a, Codes and standards.
U.S. Nuclear Regulatory Commission, Guidance on Developing Acceptable Inservice Testing Programs, Generic Letter 89-04, through Supplement 1, April 4, 1995.
U.S. Nuclear Regulatory Commission, Guidance for Inservice Testing at Nuclear Power Plants, NUREG-1482, April 1995.
U.S. Nuclear Regulatory Commission, Guidance for Inservice Testing at Nuclear Power Plants, NUREG-1482, Revision 1.
Letter, Eugene S. Grecheck, Virginia Electric and Power Company (Dominion) to NRC, North Anna Power Station Units 1 and 2, ASME Operations and Maintenance (OM) Code Relief Requests P-3 and P-4, dated April 11, 2005 (TAC Nos. MC6663, MC6664, MC6665, and MC6666).
Surry Power Station, Units 1 & 2 cc:
Ms. Lillian M. Cuoco, Esq. Office of the Attorney General Senior Counsel Commonwealth of Virginia Dominion Resources Services, Inc. 900 East Main Street Building 475, 5th Floor Richmond, Virginia 23219 Rope Ferry Road Waterford, Connecticut 06385 Mr. Chris L. Funderburk, Director Nuclear Licensing & Operations Support Mr. Donald E. Jernigan Dominion Resources Services, Inc.
Site Vice President Innsbrook Technical Center Surry Power Station 5000 Dominion Blvd.
Virginia Electric and Power Company Glen Allen, Virginia 23060-6711 5570 Hog Island Road Surry, Virginia 23883-0315 Senior Resident Inspector Surry Power Station U. S. Nuclear Regulatory Commission 5850 Hog Island Road Surry, Virginia 23883 Chairman Board of Supervisors of Surry County Surry County Courthouse Surry, Virginia 23683 Dr. W. T. Lough Virginia State Corporation Commission Division of Energy Regulation Post Office Box 1197 Richmond, Virginia 23218 Dr. Robert B. Stroube, MD, MPH State Health Commissioner Office of the Commissioner Virginia Department of Health Post Office Box 2448 Richmond, Virginia 23218