ML20203H955
| ML20203H955 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 02/23/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20203H952 | List: |
| References | |
| NUDOCS 9803030370 | |
| Download: ML20203H955 (3) | |
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UNITED STATES g
,j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30666-0001 SAFETY EVALUATION BY=THE OFFICE OF NUCLEAR REACTOR REGULATION QUALITY ASSURANCE PROGRAM DESCRIPTION CHANGE SOUTHERN NUCI FAR OPERATING COMPANY. INC.
VOGTLE ELECTRIC GENERATING PLANT. UNITS 1 AND 2 DOCKET NOS. 50-424 AND 50-425
1.0 INTRODUCTION
By letter pursuant to 10 CFR 50.54(a), dated April 8,1997, Southem Nuclear Operating Company (the licensee) submitted a request to revise the Quality Assurance Program for Vogtle Electric Generating Plant, Units 1 and 2, as described in the Final Safety Analysis Report (FSAR) Section 17.2. The licensee proposes to remove the Section 17.2.3.G requirement to complete design verification prior to release of design information for purposes of procurement, manufacturing, or installation, or to another organization for use in other design t
activities.
5 The licensee has committed in FSAR Section 1.9.64 to the following pertinent industry standard:
American National Standards Institute (ANSI) Standard 45.2.11-1974,
" Quality Assurance Program Requirements for the Design of Nuclea-Power Plants," as conditionally endorsed by Regulatory Guide 1.64 -
1976.
2.0 EVALUATION 2.1 Basis of Evaluation Title 10 of the Code of Federal Raoulations (10 CFR) Part 50, Appendix B, " Quality Assurance for Nuclear Power Plants and Fuel Reprocessing Plants," establishes Quality Assurance (QA) requirements for the operation of nuclear power plant safety-related structures, systems, and components. Appendix B, Criterion 111. " Design Control," addresses regulatory requirements for assurance of the design basis.
NRC evaluations of proposed changes to license commitments are conducted in accordance with the guidance of NUREG-0800, " Standard Review Plan * (SRP), which provides a well defined, uniform basis for staff evaluations of proposed changes to the licensing basis. Staff evaluations of proposed changes to a licensee's QA program descriptions are evaluated in accordance with SRP 17.1. The acceptance criteria for evaluating changes to the QA requirements for the design verification process are given by SRP 17.1, Section ll.3E4.
9803030370 980223 PDR ADOCK 05000424 P
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2-The licensee has committed to ANSI 45.2.11 as the basis for complying with Appendix B design control requirements. The Commissbn has conditionally endorsed ANSI 45.2.11 as an acceptable method for complying with the design control requirements of Appendix B.
- ANSI 45.2.11, Section 6, " Design Verification," provides guidance specific to Jmplementation of Appendix B design verification requirements.
2.2 Proposed Change The licenses proposes to delete the following requirement:
[ Design) verification, if other than by qualification testing of a prototype or lead production unit, is completed prior to release for procurement, manufacturing, and installation, or to another organization for use in other design activities, in those cases where this timing cannot be met, the design verification may be defened, providing that the justification for this action is documented and that the unverifed portion of the design output document and all design output documents, based on the unverified data, are appropriately identified and controlled.
l Appendix B, Criterion lil, " Design Control," requires measures to be established for the identification and control of design interfaces and for coordination among participating design organizations. The design control measures shall provide for verifying or checking the -
adequacy of desig"t, uuch as by the performance of design reviews, by the use of altemate or simplified calculational measures, or by the performance of a suitable testing program.-
As amplified by ANSI 45.2.11-1974, design verification is the process of reviewing, confirming, or substantiating the design to provide assurance that the design meets the specified design inputs. The results of desivn verification shall be clearly documented and auditable against the verification methods identified by the responsible design organization. Where changes to previously verified designs have been made, design verification shall be required for the changes, including evaluation of the effects of those changes on the overall design.
SRP 17,1 acceptance Criterion ll.3E4.b specifies that the QA program description should contain the following information concoming the design verification process.
Design verificati.,n, if other than oy qualification testing of a prototype or lead production unit, is completed prior to release for procurement, manufacturing, construction or to ar'other organization for use in other design activities, in those cases where this timing cannot be met, the design verification may be deferred, providing that the justification for this action is documented and the unverified portion of the design output document and all design output documents, based on the unverified data, are appropriately identified and controlled.
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3 The proposed change would remove this assurance of the design basis from the QA program description. Design verification provides a high degree of confidence that design changes will not. affect other systems under all modes of operation. Further, design verification provide. a reibble method for tracking subsequent changes in design, it is notti that regulatory provisions allow for use of unverified design outputs provided they are identified and controlled.
The proposed change wcold permit the use of uncontrolled, unverified ansign output to be used in subsequent design activHies and support activities, such as procurement, manufacture, or construction. Ahhough the requirement to complete design verification prior to reliance on an item's function would be retained, the practice of using unverified design output in subsequent activities would unacuptably reduce the level of assurance of the design basis.
3.0 CONCLUSION
Based on the precedir.g evaluation, the NRC staff concludes that the proposed deletion of design verification requirements does not conforra to 10 CFR Part 50, Apnendix B regulatory requirements and QA commitments previously accepted by the NkC.
I Pdncipal contnoutor: K. Heck Date:
February 23, 1998
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