ML20128H249

Safety Evaluation Authorizing Licensee Proposed Alternative to Use ASME Code Case N-508-1 for Rotation of Serviced Snubbers & Pressure Relief Valves for Sole Purpose of Testing in Lieu of ASME Requirements

ML20128H249
Person / Time
Site:	Grand Gulf
Issue date:	10/07/1996
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20128H246	List: ML20128H244 ML20128H249
References
NUDOCS 9610090287
Download: ML20128H249 (4)

Text

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SAFETY EVALUATION BY THE OFFLCE OF NUCLEAR REACTOR REGULATION

! RELATED TO RE00ESTS FOR RELIEF TO USE ASME CODE CASE N-508-1 ENTERGY OPERATIONS. INC.

! GRAND GULF NUCLEAR STATION. UNIT 1 DOCKET N0. 50-416

1.0 INTRODUCTION

By letters dated June 20 and September 5, 1996, Entergy Operations, Inc.

(the licensee) requested relief for the Grand Gulf Nuclear Station, Unit 1 (GGNS) from the requirements of Section XI, " Rules for Inservice Inspection of Nuclear Power Pl: int Components," of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), for the first and second 10-year inservice inspection (ISI) interval, in accordance with Paragraph 50.55a(a)(3)(1) of 10 CFR Part 50.

The Code of Federal Regulations,10 CFR 50.55a, requires that ISI of certain ASME Code Class 1, 2, and 3 components be performed in accordance with Section XI of the ASME Code applicable Edition and Addenda, except where specific written relief has been requested by the licensee and granted by the Nuclear Regulatory Commission (NRC) pursuant to 10 CFR 50.55a(g)(6)(i),

or alternatives approved pursuant to 10 CFR 50.55a(a)(3). In proposed alternatives, the licensee must demonstrate that: (i) the proposed alternatives provide an acceptable level of quality and safety; or (ii) compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

Title 10 of the Code of Federal Reaulations, Section 50.55a authorizes the Commission to grant relief from ASME Code requirements upon making the above necessary findings. The NRC staff's finding with respect to granting or not granting the relief request as part of the licensee's ISI program is contained in this Safety Evaluation (SE).

This SE covers a request for approval to use the ASME Code Case N-508-1 as an alternative to the ASME Code,Section XI, requirements by the licensee's letter dated June 20, 1996, with additional information provided by letter dated September 5, 1996. The licensee's ISI program for the current interval is based on the repair and replacement requirements of Section XI of the ASME Code, 1977 Edition through the Summer 1979 Addenda, and it is anticipated the 1992 Edition will be applicable to the Grand Gulf update.

ON 9610090287 961007 PDR ADOCK 05000416 P PDR

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2.0 RELIEF RE0 VEST l l

The licensee requested relief from the ASME Code,Section XI, repair and l replacement requirements for snubbers and pressure relief valves that are replaced for the sole purpose of testing later. These are not snubbers and relief valves replaced for the purpose of design changes, failures, or expiration of component lift. l The licensee proposed as an alternative to the ASME Code,Section XI requirements, to use ASME Code Case N-508-1, " Rotation of Serviced Snubber and Pressure Relief Valves for the Purpose of Testing." l 2.1 Licensee's Basis for Requested Relief The licensee proposed to use the ASME Code Case N-508-1 as an alternative to IAW-7000 for rotation of snubbers and pressure relief valves to reduce resource expenditures in regard to documentation, evaluation, and personnel ,

review effort. All technical requirements (design, fabrication, installation l and testing) are still maintained in a manner that provides an acceptable level of safety and quality that is commensurate with that afforded by compliance with the ASME Section XI requirements as currently implemented.

The requirements to be implemented in the application of the ' ode c case are adequate to ensure that the rotation of the serviced equipment is appropriately tracked and limited to mechanical removal and installation.

2.2 Evaluation Code Case N-508-1 provides an alternative to the current ASME Code,Section XI, Article IWi-7000 requirements in regard to generating a replacement plan when removing snubbers or pressure relief valves for testing.

The code case allows snubbers and relief valves to be rotated from stock and installed on components (including piping systems) within the Section XI boundary provided all the requirements stated in the code case are met. The code case was approved by the ASME on May 11, 1994, however, it has not been generically approved for use by the NRC.

The staff reviewed the June 20, 1996, submittal, and determined that additional information would be required before a determination could be made on the use of the code case alternative for GGNS. The information requested l was the following:

. Justification for the use of the code case alternative pursuant to 10 CFR 50.55a(a)(3),

. A detailed description of the implementation of the code case for each pl ant,

• A clarification of the implementation of the code case requirements in regard to "same design and construction" replacement,

• Considerations involved in the repair or replacement of snubbers in regard to the use of form NIS-2, and

• The impact of the use of the code case on the required plant snubber service life monitoring program.

By letter dated September 5, 1996, the licensee responded and provided the requested information. A summary of the respective responses follows:

. The alternative use the code case for the rotation of snubbers and relief valves for the. purpose of testing, provides a reduction in required resources while all technical requirements are.still maintained at the same level of safety afforded by compliance with the ASME Section XI 1 requirements.

. In the implementation of the code case, only the excessive controls associated with the removal and installation of snubbers and relief valves solely for the purpose testing are affected. Because of the nine provisions of the code case, only the administrative controls and documentation are eliminated for purposes of testing replacement. All other aspects of ASME Section Xi Code requirements for replacement such as design, manufacture, operational limits, expiration of life and settings are maintained.

. Entergy plans to implement the removal and installation of items of the same design and construction in a manner that ensures the items are comparable in their design, construction, and operating parameters to the extent that installation can be performed without requiring a plant design change or modification. Additionally the code case limits the use of items to be installed to those that.have been in previous service.

. The activity of the repair or replacement of a snubber code item will be performed as a typical Section XI repair or replacement with the required )

Section XI documentation generated.  !

. The existing commitments for monitoring snubber service life are unaffected by use of the code case.

In considering the licensee's proposed use of Code Case N-508-1 for GGNS, and the response to the staff iinplementation concerns, the staf f has determined that the application of the alternative is acceptable in that compliance with the ASME Code requiren nts would result in hardship without a compensating increase in the level of quality and safety. The documentation requirements and administrative controls associated with an ASME Section XI replacement are unduly burdensome for snubbers and relief valves that are replaced for the sole purpose of testing the snubbers and relief valves later and are not commensurate with the level of safety provided.

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3.0 CONCLUSION

The staff concludes that the licensee's proposed alternative to use ASME Code Case N-50C-1 for rotation of serviced snubbers and pressure relief valves.for the sole purpose of testing in lieu of ASME Section XI Code requirements, for the first and second 10-year ISI interval, is authorized by law, pursuant to 10 CFR 50.55a(3)(a)(ii), based on the determination that compliance with the ASME Code requirements will result in a hardship without a compensating increase in the level of quality and safety. ,

Principal Contributor: F. Grubelich Date: October 7, 1996 1

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