ML20195G064

Summary of 980915 Meeting with STP Nuclear Operating Co Re Graded Quality Assurance Implementation & Challenges.List of Attendees & Handout Provided by Licensee Encl

ML20195G064
Person / Time
Site:	South Texas
Issue date:	11/17/1998
From:	Alexion T NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9811200184
Download: ML20195G064 (21)

Text

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p UNITED STATES s* j 2

NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30006-4001

• • • • • November 17, 1998 LICENSEE: STP Nuclear Operating Company FACILITY: South Texas Project, Units 1 and 2 (STP)

SUMMARY

OF SEPTEMBER 15,1998, MORNING MEETING ON GRADED QUALITY ASSURANCE IMPLEMENTATION AND CHALLENGES On September 15,1998, the NRC staff met with the licensee on graded quality assurance implementation and challenges. Meeting attendees are listed in Attachment 1. The handout provided by the licensee is in Attachment 2.

The licensee outlined their graded quality assurance (QA) process for determining component safety significance. Selected results of the process were discussed for the 6 plant systems that have been evaluated to date. The licensee pointed out that a majority (89%) of the components evaluated to date were found to be low, or not risk significant. An example was

- discussed for the safety-related but non-risk significant screenwash booster pumps where the quality controis can be graded, but where the associated technical provisions such as the ASME Code, seismic qualification, Class 1E motor provisions, and ASME Section XI pump and valve testing need to be fully satisfied. The imposition of these technical controls is posing what the licensee now considers an unnecessary economic and resource burden given the low risk significance of the equipment.

Tht u ensee indicated that changing the classification of low risk significant equipment from safety-related to non-safety-related would eliminate these technical controls, but they found that changing the classification was precluded by 10 CFR 50.59 (and the staff expanded on other considerations that could possibly preclude classification, as discussed below). The licensee articulated the incongruity of needing to apply the technical requirements to the equipment in the low, and non-risk significant population given their low risk-significance as determined by a robust process which the staff found acceptable for graded QA. The licensee stated their desire to identify a mechanism where broad regulatory relief could be obtained so that design changes could be processed to allow relief from the current technical requirements. The licensee discussed the problem that seeking relief on a case-by-case basis would be extremely inefficient and overly burdensome.

The staff stated that the scope of the STP graded QA program only included relief in the area of programmatic controls associated with Appendix B to 10 CFR Part 50. The staff pointed out that other change control mechanisms, such as 50.59, relief requests, license amendments,

. and exemptions, may need to be used to modify the types of technical requirements that are problematic for the licensee. The staff was understanding of the licensee's dilemma where they desire to use risk information to make design changes to the plant. Although the STP graded QA program had not discussed the modification of technical requirements, the licensee did not realize the extent of those constraints until it began preparing for graded QA implementation.

9811200184 981117 '

PDR ADOCK 05000498 m

( hhh L

The inter relationship between the licensee's issues and the Nuclear Energy institute (NEI) proposal to make 10 CFR Part 50 more risk-informed was noted. The licensee stated their needs to achieve an expeditious resolution of the issue by the first quarter of calendar year 1999 to support a favorable cost-benefit analysis to continue the implementation of the graded QA program. ,

The complexity of the issue was discuued as the licensee needs flexibility in their  ;

implementation of a number of regulatory requirements, such as 50.59,50.36,50.2,50.55a,  !

50.65, and 50.49, in a risk-informed manner to alleviate the problem. The question arose l whether modifications to 50.59 alone could resolve the issue, and it was generally concluded that other regulatory requirements would preclude the ability of the licensee to modify the technical provisions. The primary regulations of concern to the licensee are those which define the scope of safety-related items from a deterministic standpoint.

The staff closed the meeting by stating their understanding of the problem that the licensee faces and the need to consider what options are available for handling the problem. The staff pointed out that the issue was quite complex as it relates to changing the plant's design bases and that a large number of review groups would need to be coordinated in the effort. The staff also indicated their desire to find a generic resolution path for the industry rather than just resolving the licensee's problems individually. The participants agreed to continue the dialogue on STP's graded QA program and on the status of a more risk-informed 10 CFR Part 50.

yh'f -

Y ,

h Thomas W. Alexion, Project anager Project Directorate IV-1 Division of Reactor Projects ill/IV Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Attachment:

1. List of Meeting Attendees

2. Meeting Handout cc w/atts: See next page

i. .

The inter-relationship between the licensee's issues and the Nuclear Energy Institute (NEI) proposal to make 10 CFR Part 50 more risk-informed was noted. The licensee stated their needs to achieve an expediticus resolution of the issue by the first quarter of calendar year 1999 to support a favorable cost-benefit analysis to continue the implementation of the graded QA program.

The complexity of the issue was discussed as the licensee needs flexibility in their implementation of a number of regulatory requirements, such as 50.59,50.36,50.2,50.55a, 50.65, and 50.49, in a risk-informed manner to alleviate the problem. The question arose whether modifications to 50.59 alone could resolve the issue, and it was generally concluded that other regulatory requirements would preclude the ability of the licensee to modify the technical provisions. The primary regulations of concern to the licensee are those which define the scope of safety-related items from a deterministic standpoint.

The staff closed the meeting by stating their understanding of the problem that the licensee faces and the need to consider what options are available for handling the problem. The staff pointed out that the issue was quite complex as it relates to changing the plant's design bases and that a large number of review groups would need to be coordinated in the effort. The staff also indicated their desire to find a generic resolution path for the industry rather than just resolving the licensee's problems individually. The participants agreed to continue the dialogue on STP's graded QA program and on the status of a more risk-informed 10 CFR Part 50.

ORIGINAL SIGNED BY:

Thomas W. Alexion, Project Manager Project Directorate IV-1 Division of Reactor Projects Ill/lV Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Attachment:

1. List of Meeting Attendees

2. Meeting Handout cc w/atts: See next page DISTRIBUTION: See next page Document Name: ST91598AM.MTG *See previous concurrence I/

OFC PM/PD4_1-- t LA/PD4-1 BC/HQMB* D/DRCH* BC/SPSB* D/DSSA* D h04-1 NAME TAlexioh Chaw b SBlack RSpessard RBarrett GHolahan JHannon DATE <

j h/98 llIl0 /98 11/03/98 11/04/98 11/05/98 11/10/98 k / N/98 COPY hEhNO V

YES/NO YES/NO YES/NO YES/NO YES/NO [hO OFFICIAL RECORD COPY U

4 . .

l 4

Meeting Summary of September 15,1998, dated:

HARD COPY M

PUBLIC PD4-1 R/F T. Alexion i OGC  !

ACRS  ;

E-MAIL ' i S. Collins /F. Miraglia (SJC1/FJM)

B. Boger (BAB2)

E. Adensam (EGA1)

J. Hannon (JNH)

C. Hawes (CMH2)

T. Martin (SLM3)

G. Holahan (GMH)

L. Spessard (RLS)

R. Barrett (RJB3)

S. Black (SCB)

J. Mitchell (JAM)

F. Akstulewicz(FMA)

E. McKenna (EMM)

-T. Bergman (TAB)

M. Caruso (MAC)

M.' Rubin (MPR)

R. Gramm (RAG)

S. Dinsmore (SCD1)

S. Magruder (SLM1)

J. Sorensen (JNS)

. M. Cunningham (EMC)

M. Wohl (MLW1)

J. Guttman (JXG)

M. Markley (MTM)

J. Peralta (JDP3)

S. Burgess (SDB2)

D. Lange (DJL) l l

j l

l -- _

l STP Nuclear Operating Company South Texas, Units 1 & 2 1

cc:

Mr. Cornelius F. O'Keefe Jack R. Newman, Esq.

Senior Resident inspector Morgan, Lewis & Bockius l U.S. Nuclear Reputatory Commission 1800 M Street, N.W.

l - P. O. Box 910 Washington, DC 20036-5869 Bay City, TX 77414 Mr. Lawrence E. Martin

. A. Ramirez/C. M. Canady Vice President, Nuc. Assurance & Licensing City of Austin STP Nuclear Operating Company Electric Utisty Department P. O. Box 289 721 Barton Springs Road Wadsworth,TX 77483 i

Austin,TX 78704 I Office of the Governor Mr. M. T. Hardt ATTN: John Howard, Director Mr. W. C. Gunst Environmental and Natural 4 City Public Service Board Resources Policy l

P. O. Box 1771 P. O. Box 12428 San Antonio,TX 78296 Austin, TX 78711 Mr. G. E. Vaughn/C. A. Johnson Jon C. Wood  !'

Central Power and Light Company Matthews & Branscomb P. O. Box 289 One Alamo Center i Mail Code

N5012 106 S. St. Mary's Street, Suite 700 l Wadsworth, TX 74483 San Antonio,TX 78205-3692 INPO Arthur C. Tate, Director l Records Center Division of Compliance & Inspection 700 Galleria Parkway Bureau of Radiation Control Atlanta, GA 30339-3064 Texas Department of Health  ;

1100 West 49th Street

. Regional Administrator, Region IV Austin, TX 78756 U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Jim Calloway Arlington, TX 76011 Public Utility Commission of Texas Electric industry Analysis D. G. Tees /R. L. Balcom P. O. Box 13326 Houston Lighting & Power Co. Austin, TX 78711-3326 l4; P. O. Box 1700 Houston, TX 77251 Mr. William T. Cottle President and Chief Executive Officer Judge, Matagorda County STP Nuclear Operating Company.

E Matagorda County Courthouse South Texas Project Electric L .1700 Seventh Street . Generating Station l Bay City, TX 77414 - P. O. Box 289 Wadsworth, TX 77483 i

l . . .

l l

l l MEETING BETWEEN STP NUCLEAR OPERATING COMPANY AND NRC I

l GRADED QUALITY ASSURANCE IMPLEMENTATION AND CHALLENGES l

LIST OF ATTENDEES i

Name Oraanization S. Rosen STP Nuclear Operating Company i M. McBurnett STP Nuclear Operating Company l R. Grantom STP Nuclear Operating Company i G. Schnizel STP Nuclear Operating Company S. Thomas STP Nuclear Operating Company B. Bradley NEl T. Pietrangelo NEl

L. Neal NEl

! S. Floyd NEl T. Sutter Bechtel J. Bastin Westinghouse J. Dozier NUS Info Services R. Huston Licensing Support Services J. Weil McGraw-Hill -

G. Holahan NRC l L. Spessard NRC

! J.Hannon NRC R. Barrett NRC S. Black NRC J. Mitchell NRC F. Akstulewicz NRC E.McKenna NRC T. Bergman NRC M. Caruso NRC D.Lange NRC M. Rubin NRC R. Gremm NRC S. Dinsmore NRC S. Magruder NRC J. Sorensen NRC

! M. Cunningham NRC

! M. Wohl NRC J. Gunman NRC M. Markley NRC J. Peralta NRC l S. Burgess NRC

! T. Alexion NRC l

! ATTACHMENT 1 l

South Texas Project Review Of The Graded Quality Assurance j

Implementation And ChaIIenges s

Presented by South Texas Project Personnel i

to the -

Nuclear Regulatory Commission Staff September 15,1998 Rockville, MD

~

I l

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INTRODUCTION l

Agenda:

GeneralIntroduction -

Mark McBurnett 1

Problem Statement -

Steve Thomas t

PSA Insight -

Rick Grantom Possible Solutions -

Ma~rk McBurnett i

General Discussions -

All .

2 l,

INTRODUCTION (Cont'd)

Purpose:

- To communicate existing challenges with Graded Quality Assurance implementation and to seek agreeable solutions Desired Outcomes:

- Communicate the existing limitations of 10CFR50.59 during implementation of Graded Quality Assurance

- Agree upon a success path to effectively address the GQA implementation challenges

GRADED QUALITY ASSURANCE PROCESS 4-P System or Component Y PSA High lw % PSA Med }m % PSA Low lw % Not Modeled j 4-1 Y'S l Yes l l Yes l

+

D If RAW between 10 & 100 & 1r E

'I FV<0.005, then further evaluation > > {

required 3r R 4- M Assess risk significance based Mode Change or Mitigates Could fait risk Could directly I Used .m N on PSA rankings and/or deterministic evaluation 4-- shutdown safety significant?

4-- EOPs?

4-- acc dents or 4--

transients?

significant system?

4-- :ause initiating event?

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STP GRADED RISK SIGNIFICANCE .

. RESULTS TO DATE klh -

System Total Safety- Non- High Medium Low Not Risk Components Related Safety- Significant Related Chemical and 3,073 1711 1362 4 178 433 2457 Volume Control

% S. Essential; 'A _ .J1,406m,c , ., M1058" ' 1,348 ~48 ~

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.127

... .199' 1032

_. .- .. ,..m ..

+ Cooling WaterJ ^ ' ' =- '

+, '< i3% - ' 9% -

!14% - . : 74%

Diesel 5,603 2840 2763 393 341 493 4376 Generators Radiation 1,822 388 1434 0 0 189 1649 Monitoring Reactor Coolant 1,389 652 737 294 266 396 433 System Electrical 2,280 1263 1017 90 86 1036 1968 Auxiliary Building HVAC Totals 15573 7912 7661 829 998 2746 11000

% of Totals 51 % 49 % 5% 6% 18 % 71 %

5

. _ . .. _ _ . . - .. .. - . . . - . .. . - . - - .-.. - . .- .. . ~ . _

STP GRADED QUALITY ASSURANCE .

ESSENTIAL COOLING WATER SYSTEM

. _ . _ . , . _ _ _ _ _ . _ ._ _ . _ _ _ . _ . . _ _ _ _ _ . _ _ . _ . . _ . ..__z_._... . . _ _ _ _

_ _ . _ _ . .EW SYSTEM - GRADED QA EVALUATION

SUMMARY

BY COMPONENT TYPE SAFETY RELATEC l lOUAL CLASS 7 (LIMITED QA) l l ---NON-OUALITY RELATEC ALL

, [ ,

SRAOC l-FULL] SASIC l l TARGET l TARGETd -NO OA- l l -ASME LIMITED- l -NON ASME LTD-COMPONENTS 9fSC- HIGH MED LOW NRS MED LOW NRS TOTAL HIGH MED LOW NRS TOTAL HIGH MED LOW NRS TOTAL TOTAL EXTBRKRS I I 01 01 01 01 1 1 81 1 81 6 61 102] I 01 01 01 01 01 1 01 01 01 Of 01 1 1021 i

ELECT. CABINEIS I I 01 01 01 01 1 01 01 01 01 I 01 01 01 01 01 1 01 01 01 71 71 1 71

' Oli 01 01 01 1 01 I 01 01 01 01 01 1 01 01 01 11 11 1 1 91 FILTERS I I Of 1 81 01 HEATXERS I l 01 01 61 0l l 01 01 01 61 1 01 01 01 01 Of l 01 01 01 01 01 1 61 SWITCHES I l 01 01 01 01 1 01 1 81 1 21 301 1 01 01 1 21 481 601 I 01 01 01 61 61 1 9 61 INST. 000PS l 1 01 01 Oi 01 1 01 01 01 01 1 01 01 01 11 11 1 01 01 01 01 01 l 11 INST. CON T ROLLERSI l 01 01 01 0l l 01 01 01 01 1 01 01 01 1 21 121 1 01 01 01 61 61 l 1 81 I 11ll 01 01 01 111 1 01 01 61 1351 1411 1 Oi 01 01 21 21 1 1541 INDICATORS I 01 01 01 I 2811 01 01 541 961 1 01 01 01 861 861 1 01 01 01 1 51 151 l 1971 TRANSMIT TERS I 01 01 1 41 TRAV. SCREENS I l 01 01 01 Oli 01 01 61 61 1 01 01 01 Or 01 1 61 01 01 01 01 l J di 7011 01 Of 01 991 1 01 01 01 O! 01 1 01 01 01 51 51 1 1041 l PfPE I l 01 251

- C esai.w. e-

. l 61 01 Ol**w 5 si 1 01 01 01 1 21 1 01 01 01 01 01 I 01 01 01 01 01 1 1 21 RELAYS I l 01 01 01 01 1 01 01 91 91 1 01 01 01 01 01 1 01 01 01 01 Of I 91 VALVES I I 361 661 811 10011 01 401 3401 663] I 01 01 01 01 OI l 01 01 01 61 61 I 6691 VALVE OPER. l l 61 01 01 01 1 01 01 01 61 1 01 01 Of 01 01 1 01 01 01 01 01 I 61 215 18 487 1058 0 0 18 282 300 0 0 0 48 48 1406 7Z7TNS' 48 109 105 7G

• OFSR- 4.52 10.32 S.9% 20.32 1.7% 7.2% 46.Ct 1058 0.0% 0.0% 1.3% 20.1 % 21.3% 0.0% 0.0% 0.0% 3.4% 3.4% 100.0%

'

• OF727TNI 3.4% 7.8% 7.5% 15.3% 1.32 5.4% 34.6% 75.2%

MOTES: 1. ASME LIMITED consists of time non+ ugh tisk componerts iderdied h MED as ASME cisss.except for valves .<=1*. ASME LIMITED totals are shcmn because these w.we wadd have to be procued as CDDE and therefore procuement cost savings nodd be Emited even for low risk or rmnsk sedicart corvonerts.

2. Qua9y Cass 7 consists of 7B ($tation Blackadt 7F (Fire Protectiont 7P (DAMS Cat 2L 7R 1Rackastel or 7S [ Seismic 2/11 6

STP GRADED QUALITY ASSURANCE ~

DETERMINISTIC SAFETY CLASSIFICATION

- ECW is designed in accordance with Regulatory Guide 1.27 (Ultimate Heat Sink for Nuclear Power Plants)

.: - Per Regulatory Guide 1.26 (Quality Group Classification and Standards for... Components ofNuclear Power Plants), ECW Screen Wash Booster Pumps are:

-ASME Section III, Code Class 3 -

-Seismic Category I

-Section XI Pump and Valve Tesiting

-Class 1E Motors 7

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i STP GRADED QUALITY ASSURANCE .l THE SPECIFICS i

STPEGS UFSAR Essential Cooling Water (ECW) Screen Wash Booster Pump A traveling water screen is provided upstream of each ECW pump to minimize debris entering the ECWS which could cause damage to the pumps or could clog HX tubes.

Screen wash booster pumps, which take suction from the ECW pump discharge piping, provide water to wash each traveling water screen.

__-_-______-_____-__________-_______Y

STP GRADED QUALITY ASSURANCE THE PROBLEM t

- 50.59 review must determine that changes to the facility do not 1 represent an Unreviewed Safety Question

- 50.59 review is a deterministic process

- 50.59 is a regulatory test...not a test of safety or risk significance .

- As currently written and enforced, we are prohibited from using PRA as a 50.59 justification for changes driven by GQA 10

South Texas Project Contribution to .

Core Damage Frequency External Events Other External Total CDF: 9.08E-06 Events ' *FLECW CDF Due to External Events: 8.74E-07 4.8% 4.9% CDF Due to External Flooding: 4.42E-07 Transients, SGTR, LOCAs, Support

, ECW Failure Due to System Faults Breach of MCR 90.4 %

I1

South Texas Project Contribution to .

Core Damage Frequency Key Assumptions:

0 3sume_

FSAR does not a% failure of ECP given an MCR breach PRA conservatively assumed 10% of MCR breaches failed ECP with no credit for screen wash booster pumps due to initiating event frequency being already sufficiently low. -

12

t-STP GRADED QUALITY ASSURAlVCE .

THE REGULATORY DILEMVIA  :

- Majority of components currently classified safety-related are not i risk significant

' - Classifications as safety-related invokes other requirements (e.g.

seismic, ASME, etc.)

- Consequently:

- Code (ASME, IEEE, etc.) requirements must be met i

- Seismic capability must be denionstrated j

- Little real relief gained from larg effort to implement GQA 13  ;

~

STP GRADED QUALITY ASSURANCE 50.59 PROCESS CURRENT PROCESS OPTIONS Screening In SAR Risk Based Evaluation 1. Probability Use Risk-based

2. Consequences Thresholds

3. Accident of Different Type

4. Margin 14

STP GRADED QUALITY ASSURANCE  : .

POSSIBLE SOLUTIONS  !

i

- Allow a License Amendment modifying applicability of regulations j specific to STP that would allow changes on a risk basis (could be

! considered a pilot for risk based 50.59)

- Change the regulations to allow changes on a risk basis

- Proposal in SECY 98-171 provides some relief, but ' minimal' as described is not risk informed -

- Risked based 50.59 rule making is in conceptual development

- Provide an interpretation of the current regulations which explain that these changes are not USQs 15