ML20236N585

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Responds to TIA Requesting NRR to Review ANO-1 TS Requirements Pertaining to Operability of Pressurizer Safety Valves
ML20236N585
Person / Time
Site: Arkansas Nuclear  Entergy icon.png
Issue date: 11/25/1997
From: Hall J
NRC (Affiliation Not Assigned)
To: Gwynn T
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20236J990 List: ... further results
References
FOIA-98-155 50-313-94-24, 50-368-94-24, NUDOCS 9807150184
Download: ML20236N585 (4)
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/ Sa UNITED STATES g NUCLEAR RECULATCRY COMMISSION

%y*esse MEMORANDUM To: Thomas P. Gwynn, Director Division of Reactor Projects Region IV FROM: James R. Hall, Acting Director M Project Directorate IV-1 Division of Reactor Projects I /IV Office of Nuclear Reactor Re ation

SUBJECT:

TASK INTERFACE AGREEMENT (TIA), ARKANSAS NUCLEAR ONE, UNIT I (ANO-1) PRESSURIZER SAFETY VALVE SET POINTS, 95TIA005 We received the subject TIA by memorandum dated April 3, 1995. The TIA requested NRR to review ANO-1 Technical Specification (TS) requirements pertaining to the operability of pressurizer safety valves. The TIA addressed issues identified by Unresolved Item 313/9424-02 in Inspection Report

  • 50-313/94-24; 50-368/94-24. As described in the inspection report, the two ANO-1 pressurizer safety valves were found to be +4.5 and +3.1 percent cut-of-tolerance during licensee pressure tests. The licensee did not submit a Licensee Event Report to report the out-of-tolerance condition and it became evident from subsequent discussions that the pressurizer safety valve operability requirements were not clearly discernable from the ANO-1 TSs.

The TIA requested review and guidance on the following two issues:

(1) What constitutes operability of the pressurizer code safety valves as l required by Unit Technical Specification Limiting Condition for Operation, j Section 3.1.1.37  !

(2) What is the setpoint and range of the pressurizt.r code safety valves that is required to be in compliance with ANO, Unit 1, Technical Specifications, Safety Limits, Section 2.2.27 Is it acceptable to be outside these limits and the valves be considered operable?

NRR staff in the Mechanical Engineering, Technical Specifications and Reactor Systems Branches evaluated this issue. The difficulty identified in the TIA appears to be the result of a gradual change in the format and content of TSs over the time since AND-1 was first licensed. The 1970's vintage ANO-1 TSs describe pressurizer safety valve operability i terms of the ASME Boiler and Pressure Vessel Code. For some reason the TS Baus were revised several times since ANO-1 was licensed and appear to describe safety valve operability in terms similar to those used in Standard TSs.

CONTACT: George Kalman 301-415-1308 9807150184 980624

-155 PDR

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TS 2.2.2 defines safety valve operability in tems of the American Society of ,

Mecharical Engineers (ASME), Boiler and Pressure Vessel Code. The Code

! requires the nominal pressure setting of at least one safety valve to be no l greater than the design preshore of the vessel, additional valves may have l higher nominal settings, but in no case greater than 105 percent of the design pressure. Standard TSs include a specific value for safety valve settings under the Limiting Condition for Operation (LC0) section. The bases section of the Standard TSs propose that tte LC0 value for the safety valve settings be +/- 3% of the design pressure. The Ig70's vintage AND-1 TSs do not de"ine  !

operability in tems of safety valve setpoints, however the Bases Section of the TS discuss safety valve requirements in terms that are currently used in the Standard TSs.

Safety valve operability criteria in either the ASME Code or the Standard TSs are adequate to ensure safe operations. The unresolved ites that led to the subject TIA is not an operational safety issue but rather a question of I' l whether the licensee should have written a Licensee Event Report when the l pressurizer safety valves were found to be out-of-tolerance. In all cases -

when safety valves are found out-of-tolerance, they are reset to the same l acceptable tolerance (+/- 1% of the design pressure) before the primary system 4 l 1s repressurized.

To resolve this matter, we have written a letter (attached) to the licensee describing the dichotomy between operability criteria for safety valves in the TSs versus the TS bases. We requested the licensee to clarify the safety valve operability requirements either by completing the conversion process to Standard TSs or by submission of a TS amendment for review if the Standard TS conversion is significantly delayed. We have also requested that, until the TS is clarified, the license return to their previous practice of defining TS operability consistent with the +/- 3% of design pressure criteria.

Based on the lack of safety significance of this issue and the inconsistencies between the TS and the TS bases, we do not consider it appropriate to cite the ,

licensee for their failure to follow unclear requirements. Our letter to the '

licensee documents our agreement that existing ANO-1 TS pressurizer safety  :

l valve operability requirements may be interpreted as being met if they are in accordance with current Standard TS criteria and that the matter will be clarified through modified TSs. .

We propose that you close-out Unresolved Item 313/9424-02 on the basis of our  !

1etter to the licensee. Thank you for calling this matter to our attention.

l Docket No. 50-313 i

l

Attachment:

Letter to Hutchinson cc w/att: C. Hehl, RI J. Johnson, RII G. Grant, RI!!

l l

___ _ _ _ _ _ _ . . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ J

TS 2.2.2 defines safety valve operability in terms of the American Society of

. Mechanical Engineers (ASME), Boiler and Pressure Vessel Code. The Code requires the nominal pressure setting of at least one safety valve to be no greater than the design pressure of the vessel, additional valves may have higher nominal settings, but in no case greater than 105 percent of the design pressure. Standard TSs include a specific value for safety valve settings under the Limiting Condition for Operation (LCO) section. The bases section of the Standard TSs propose that the LCO value for the safety valve settings be +/- 3% of the design pressure. The 1970's vintage ANO-1 TSs do not define operability in terms of safety valve setpoints, however the Bases Section of the TS discuss safety valve requirements in terns that are currently used in the Standard TSs.

Safety valve operability criteria in either the ASME Code or the Standard TSs are adequate to ensure safe operations. The unresolved item that led to the subject TIA is not an operational safety issue but rather a question of whether the licensee should have written a Licensee Event Report when the l pressurizer safety valves were found to be out-of-tolerance. In all cases when safety valves are four.1 out-of-tolerance, they are reset to the same acceptable tolerance (+/- 1% of the design pressure) before the primary system is repressurized.

To resolve this matter, we have written a letter (attached) to the licensee describing the dichotomy between operability criteria for safety valves in the TSs versus the TS bases. We requested the licensee to clarify the safety valve operability requirements either by completing the conversion process to Standard TSs or by submission of a TS amendment for review if the Standard TS conversion is significantly delayed. We have also requested that, until the TS is clarified, the license return to their previous practice of defining TS operability consistent with the +/- 3% of design pressure criteria. .

Based on the lack of safety significance of this issue and the inconsistencies between the TS and the TS bases, we do not consider it appropriate to cite the licensee for their failure to follow unclear requirements. Our letter to the licensee documents our agreement that existing ANO-1 TS pressurizer safety valve operability requirements may be interpreted as being met if they are in accordance with current Standard TS criteria and that the matter will be clarified through modified TSs.

We propose that you close-out Unresolved Item 313/9424-02 on the basis of our letter to the licensee. Thank you for calling this matter to our attention.

Docket No. 50-313 l

Attachment:

Letter to Hutchinson cc w/att: C. Hehl, RI i J. Johnson, RII DISTRIBUTION: See next page

! G. Grant, RIII DOCUMENT NAME: AR195005195005TIA See previous concurrence

  • OFC PH/PD4-1 LA/PD4-1 EMEB* TSB* (A)SRXB* (A)PD4-J , DD/DRPW*

NAME GKalman:sp CHawe N RWessman WBeckner JLyons rm[ EAdensam DATE / /97 H 8 3/97 5/09/97 7/08/97 5/19/97 II/L5/97 10/23/97 COPY YES/NO YES/NO YES/NO YES/NO YES/NO YES/NO YES/NO l OfflCIAL RECORD COPY

l 9

e DISTRIBUTION FOR MEMO RE: TIA AND-1 (95TIA005) Dated: November 25, 1997 Docket File l PDIV-1 r/f 1 JClifford l GKalman l CHawes l EAdensam (EGA1) l MBoyle, (MLB4) DRPE

AChafee TGwynn, RIV KKennedy, SRI, RIV SBloom (5081)

GHammer RWessman WBeckner l RJones l

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