ML061280500
| ML061280500 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 05/01/2006 |
| From: | Holm D Constellation Generation Group, Ginna |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML061280500 (11) | |
Text
Dave Holm Plant General Manger R.E. Ginna Nuclear Power Plant, LLC 1503 Lake Road Ontario, New York 14519-9364 585.771A.3635 Dave.A.Holm @ constellation.com Constellation Energy Generation Group May 1, 2006 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
SUBJECT:
Document Control Desk R.E. Ginna Nuclear Power Plant Docket No. 50-244 Response to Request for Additional Information Regarding Relief Request PR-3
References:
(1)
Letter from P. Milano, NRC, to M. Korsnick, Ginna LLC,
Subject:
R.E. Ginna Nuclear Power Plant, Request for Additional Information RE: Relief Request PR-3 for use of Later Code Edition (TAC No. MD0316), dated April 13, 2006.
(2)
Letter from M. Korsnick, Ginna LLC, to NRC Document Control Desk,
Subject:
Submittal of Relief Request PR-3 Related to the Requirements of 10CFR50.55a(f), dated March 7, 2006.
In Reference 1, the NRC provided a Request for Additional Information (RAI) related to a proposed relief request for Ginna Station concerning the ASME Section XI Inservice Testing Program (Reference 2).
The purpose of this letter is to provide the response to the questions documented in Reference 1 (see enclosure). Also included in this submittal is the request for use of a later code edition, which is being resubmitted in the format suggested in the Nuclear Energy Institute (NEI) White Paper (included in NRC Report NUREG-1482, Revision 1, "Guidelines for Inservice Testing Programs at Nuclear Power Plants")
and a revised Relief Request PR-3.
No new commitments are being made in this letter.
Due to the desire to suspend the current testing protocol that requires a reactivity change and also introduces a potential for intrusion of service water into the steam generators, written or verbal approval of the attached requests is desired prior to May 21, 2006.
Should you have questions regarding the information in this submittal, please contact Mr. Robert Randall at (585) 771-3535 or Robert.Randall @constellation.com.
Very truly you s, Dave A. Holm AoI7 fo/*
Enclosures (1) Response to NRC Request for Additional Information (RAI)
(2) Request in Accordance with 10 CFR 50.55a(f)(4)(iv) For use of Subsequent ASME Code Edition and Addenda (3) Relief Request PR-3 cc:
S. J. Collins, NRC P.D. Milano, NRC Resident Inspector, NRC (Ginna)
Response to NRC Request for Additional Information (RAI)
Response to NRC Request for Additional Information (RAI)
The response to the RAI will be structured as follows. The items in bold below are the questions provided by the NRC in the RAI dated April 13, 2006. A response to each item is then provided by R.E. Ginna.
RAI 1: The description of alternate testing in RR No. PR-3 states that the licensee will perform quarterly pump discharge pressure, differential pressure and vibration measurement for the two Group A AFW pumps and a differential pressure measurement for the two Group B SAFW pumps.
Will rotational speed measurement also be performed on the two Group A and two Group B SAFW pumps, as required by Table ISTB-3000-1 of the ASME OM Code? If pump rotational speed will not be measured, provide a technical basis.
Response: The rotational speed measurement required by Table ISTB-3000-1 is for variable speed pumps. The two Group A pumps and the two Group B SAFW pumps are centrifugal pumps powered by constant speed motors, and as such the speed measurement is not required.
RAI 2: NRC Generic Letter (GL) 89-04, Supplement 1, indicates that licensees should consider vendor records of degradation at other facilities (operating experience) when evaluating alternative testing. GL 89-04 also identifies the absence of flow instrumentation in the minimum flow lines as a potential generic deficiency. In addition, Template 1 from the Nuclear Energy Institute (NEI)
White Paper (included in NRC Report NUREG-1482, Revision 1, "Guidelines for Inservice Testing Programs at Nuclear Power Plants") suggests that precedents, which have similar situations, and NRC approval be identified. As specified in the introduction section of ASME OM Code, code cases may be issued for alternatives when the need is urgent. In the interest of obtaining a complete review by the Code Committee and improving regulatory efficiency, the use of code inquiries, including code cases, is the preferred method to address generic alternatives from the Code.
In Relief Request No. PR-3, the licensee did not address industry-wide operating experience, plant-specific past precedence, or ASME Code inquiries for this type of alternative to the Code.
Identify if there are any industry-wide operating experiences, plant-specific precedents, or ASME OM Code Inquiries for alternatives to Code requirements that are similar to this type of relief request. If such experience, precedents and inquiries exist, evaluate their applicability to this relief request, and describe any compensatory actions that will be performed in lieu of the Code requirements.
Response: The attached revised Relief Request PR-3 provides a prior precedent. A similar relief request (IST-3-P-3) was approved for the Southern California Edison San Onofre Nuclear Generating Station (SONGS), Units 2 and 3, in correspondence dated April 21, 2004 (ML041140166). The bases for the relief was that using a fixed resistance flow path is an acceptable alternative to the Code requirements as per NUREG-1482, NRC Staff Position 9,
'Pump Testing Using Minimum-Flow Return Line With Or Without Flow Measuring Devices.'
This methodology provides for the acquisition of repeatable differential pressure and vibration measurement, which is an adequate means of monitoring pump degradation.
Similar to SONGS, the cost of installing either temporary or permanent flow instrumentation at Ginna Station imposes an undue burden without a compensating increase in the level of quality and safety.
Ginna also contacted an OM Code Main Committee member and determined that there are no ongoing Inquiries or Code Cases related to the non-instrumented mini-flow line issue.
RAI 3: In its letter dated March 7, 2006, the licensee identifies that the relief request is being submitted in accordance with 10 CFR 50.55a(f)(4)(iv). This regulation applies to use of later Code Editions and Addenda rather than an impracticality. The licensee identifies that the basis for the relief request is that the Code is impractical and that costly major hardware modifications would be required. As identified in the NEI White Paper, Template 4 is appropriate where the IST Code is impractical and the licensee requests relief under 10 CFR 50.55a(f)(5)(iii). Template 4 identifies that information concerning the impracticality and burden be included in the relief request.
Clarify the basis for this relief request, and/or reconsider the appropriate regulation.
Response: The original March 7, 2006 submittal was requesting the adoption of a subsequent edition and addenda of the ASME code in accordance with 10 CFR 50.55a(f)(4)(iv) within the cover letter. This request is now being separately submitted within Enclosure 2.
The, relief request (PR-3) attached to the original submittal did not state which regulation it was being requested under, though it did use the term 'impractical'. After further review it has been determined that the request should have been submitted as a hardship or unusual difficulty without a compensating increase in level of quality and safety in accordance with 10 CFR 50.55a(a)(3)(ii). The revised Relief Request PR-3 is being resubmitted within Enclosure 3.
Request in Accordance with 10 CFR 50.55a(f)(4)(iv)
For use of Subsequent ASME Code Edition and Addenda
Request in Accordance with 10 CFR 50.55a(f)(4)(iv)
For use of Subsequent ASME Code Edition and Addenda 1
ASME Code Component(s) Affected Components: Auxiliary Feedwater Pumps:
GROUP A PUMPS "A" preferred motor-driven AFW pump - PAFOlA "B" preferred motor-driven AFW pump - PAFOB GROUP B PUMPS Turbine-driven AFW pump - PAF03 "C" standby motor-driven AFW pump - PSF01A "D" standby motor-driven AFW pump - PSFOIB Class:
3 Quantity:
5 pumps
- 2.
Applicable Code Edition and Addenda
ASME Boiler & Pressure Vessel Code - Section XI Division 1, "Rules for Inservice Inspection and Testing of Nuclear Power Plant Components", 1989 Edition, ASME/ANSI OMa-1988, "Operation and Maintenance of Nuclear Power Plants" Part 6.
- 3.
Proposed Subsequent Code Edition and Addenda (or Portion)
All related requirements of subsections ISTA, "General Requirements" and ISTB, "In-service Testing of Pumps in Light-Water Reactor Nuclear Power Plants" of the ASME OM Code, 2001 Edition through 2003 Addenda, for the Group A and Group B Auxiliary Feedwater Pumps.
- 4.
Related Requirements No modifications or limitations are listed in 10 CFR 50.55a(b) that pertain to the sections requested for use. There is no information in the Federal Register Statement of Considerations (69 FR 58804) for the proposed incorporation, by reference, of ASME OM Code-2001 into 10 CFR 50.55a(b) that is pertinent to the sections requested for implementation.
- 5.
Duration of Proposed Request This request is for the remainder of the 4th 10-year program interval that shall terminate on December 31, 2009.
Relief Request PR-3
GINNA STATION IN-SERVICE TESTING PROGRAM RELIEF REQUEST PR-3 Proposed Alternative In Accordance with 10 CFR 50.55a(a)(3)(ii)
Hardship or Unusual Difficulty without Compensating Increase in Level of Quality and Safety 1.0 ASME Code Component(s) Affected Components: Auxiliary Feedwater Pumps:
Group A Pumps - PAFOlA, PAFO0B Group B Pumps - PSF01A, PSFO1B Class:
3 Quantity:
4 pumps 2.0
Applicable Code Edition and Addenda
ASME OM Code, 2001 Edition through 2003 Addenda 3.0
Applicable Code Requirement
ISTB-3550: Flow Rate. When measuring flow rate, a rate or quantity meter shall be installed in the pump test circuit. If a meter does not indicate the flow rate directly, the record shall include the method to reduce the data. Internal recirculated flow is not required to be measured. External recirculated flow is not required to be measured if it is not practical to isolate, has a fixed resistance, and has been evaluated by the owner to not have a substantial effect on the results of the test.
Group A Pumps:
ISTB-5121 (b): The resistance of the system shall be varied until the flow rate equals the reference point. The differential pressure shall then be determined and compared to its reference value. Alternatively, the flow rate shall be varied until the differential pressure equals the reference point and the flow rate determined and compared to the reference flow rate value.
ISTB-5121(c): Where system resistance cannot be varied, flow rate and pressure shall be determined and compared to their respective reference values.
Group B Pumps:
ISTB-5122 (b): The differential pressure or flow rate shall be determined and compared to its reference value.
ISTB-5122(c): System resistance may be varied as necessary to achieve the reference point.
4.0
Reason for Request
Relief is requested from the requirement to measure pump flow during the performance of the specified Group A and Group B testing of Auxiliary Feedwater (AFW) pumps. Testing of these pumps is performed using minimum flow recirculation lines not equipped with instrumentation to provide the measurement of pump flow as required by the Code. Flow is not variable due to an installed flow orifice which establishes a nominal 40 gpm flow rate when the pump is operated in the recirculation mode. The pump minimum flow recirculation line must be used when these pumps are tested on a quarterly interval during power operation because this is the only flow path available that does not challenge the normal operation of the Unit. Minimum flow lines are not designed for pump testing purposes.
It is estimated to cost more than $60,000 annually to install and maintain temporary flow measurement devices (ultrasonic flow meters and their associated hardware, software, precision "wet-calibration" and maintenance costs) to support quarterly testing for the pumps. In addition, the use of temporary flow measurement equipment would pose a personnel safety risk given the approximate 20 foot overhead elevation of the associated minimum flow recirculation piping.
Installation of permanent flow devices on the Auxiliary Feedwater minimum flow recirculation lines is estimated to cost more than $300,000. Therefore, the requirement to install temporary or permanent instrumentation to meet the Code requirements imposes an undue burden for the information that would be gained.
6.0 Proposed Alternative and Basis for Use Proposed Alternative:
Group A quarterly testing of the AFW pumps will be performed on mini-flow recirculation measuring the discharge pressure, differential pressure across the pump, and measuring vibration in lieu of measuring flow. Group B quarterly testing of the AFW pumps will be performed on mini-flow recirculation measuring the differential pressure across the pump in lieu of measuring flow.
Note: Pump flow rate will be measured during performance of biennial Comprehensive Pump Test (CPT) when an instrumented flow path is available.
Basis for Use:
The AFW pumps each have a non-instrumented minimum-flow path that can be utilized for the respective Group A and Group B tests. The minimum flow lines used for these pumps provide a fixed resistance flow path from the pump discharge to the Condensate Storage Tanks and then back to the suction of each
pump. During the performance of the quarterly pump testing, pump differential pressure is measured and trended. This provides a reference value for differential pressure that can be duplicated during subsequent tests in accordance with OM-ISTB-3300 (d).
The performance of pump tests using a fixed resistance flow path is an acceptable alternative to the Code requirements as per NUREG -1482, NRC Staff Position 9, 'Pump Testing Using Minimum-Flow Return Line With Or Without Flow Measuring Devices.' This methodology provides for the acquisition of repeatable differential pressure measurement, which is an adequate means of monitoring pump degradation.
Therefore, the cost of installing either temporary or permanent flow instrumentation imposes an undue burden without a compensating increase in the level of quality and safety.
6.0 Duration of Approved 10 CFR 50.55a Request This request is for the remainder of the 4th 10-year program interval that shall terminate on December 31, 2009.
7.0 Precedents A similar relief request (IST-3-P-3) was approved for the Southern California Edison San Onofre Nuclear Generating Station (SONGS), Units 2 and 3, in correspondence dated April 21, 2004 (ML041140166).
8.0 References NUREG-1482, Guidelines for Inservice Testing at Nuclear Power Plants, November 1993.