ML20154M215

Forwards SER & Request for Addl Info Re Response to Generic Ltr 83-28 Concerning Salem ATWS Followup Actions.Tabulation of Remaining Open Items Encl

ML20154M215
Person / Time
Site:	South Texas
Issue date:	03/07/1986
From:	Kadambi N Office of Nuclear Reactor Regulation
To:	Goldberg J HOUSTON LIGHTING & POWER CO.
Shared Package
ML20154M219	List: ML20154M215 ML20154M220
References
GL-83-28, NUDOCS 8603130378
Download: ML20154M215 (4)

Text

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Docket Nos.: 50-498 and 50 499 AUUl07IJ86 Mr. J. H. Goldberg Group Vice President - Nuclear Houston lighting and Power Company Post Office Box 1700 Houston, Texas 77001

SUBJECT:

CONFORMANCE OF THE SOUTH TEXAS PROJECT, UNITS 1 AND 2 TO THE SALEM ATWS F0ll.0W-UP ACTIONS IN GENERIC LETTER 83 28 This letter is to acquaint you with the status of conformance to the items in the Generic letter 83-28 for South Texas, and indicate what actions remain to be taken so that the Project can be brought into conformance in this area. The Enclosure 1 is a tabulation of each of the items contained in the Generic letter showing either the status or referring to a subsequent Enclosure which provides an evaluation. As shown in the tabulation, several of the items remain open, either due to incomplete NRC staff review or because additional information is needed from you.

The action requested of you by this letter is to provide the additional information as indicated in the Enclosures. Subsequent requests for additional information may be forthcoming as the staff complete the reviews. Please call me at 301-492-7272, if you have any questions.

Sincerely, N. P. Kadambi, Project Manager PWR Project Directorate #5 Division of PWR licensing.A En-losures:

1. G. L. 83-28 Items Summary

2. SAIC TER on Item 1.2

3. NRC Staff SER on Item 4.3 cc: See next page Distribution:

' Docket file - E. Jordan NRC PDR B. Grimes local PDR J. Partlow PD#5 Reading Files P. Kadambi T. Novak M. Rushbrook OELD ACRS (10) 0FC :PD#5  ;  :  :  :  :  :  :

.....:..... A .:._____....__:________....:........____:.. ___......:-__...... __:__.........

NAME :NPKadambi  :  :  :  :  :  :

DATE : 6h/ 7/86  :  :  :  :  :  :

8603130370 860307 0FFICIAI. RECORD COPY PDR ADOCM 05000498 A PDR

Mr. J. H. Goldberg Houston I.ighting and Power Company South Texas Pro.iect CC:

Brian Berwick, Eso. Resident inspector / South Texas Assistant Attorney General Project Environmental Protection Division c/o V. S. Nuclear Regulatory Commission P.O. Box 12548 P. O. Box 910 Capitol Station Bay City, Texas 77414 Austin, Texas 78711 Mr. Jonathan Davis Mr. J. T. Westermeir Assistant City Attorney Manager, South Texas Project City of Austin Houston lighting and Power Company P. O. Box 1088 P. O. Box 1700 Austin, Texas 78767 Houston, Texas 77001 Ms. Pat Coy Mr. H. L. Peterson Citizens Concerned About Nuclear Mr. G. Porkorny Power City of Austin 5106 Casa Oro P. O. Box 1088 San Antonio, Texas 78233 Austin, Texas 78767 Mr. J. B. Poston Mr. Mark R. Wisenberg Mr. A. Von Rosenberg Manager, Nuclear f.icensing City Public Service Board Houston,l.ighting and Power Company P. O. Box 1771 P. O. Box 1700 San Antonio, Texas 78296 Houston, Texas 77001 Jack R. Newman, Esq. Mr. Charles Halligan Newman & Poltzinger, P. C. Mr. Burton I.. I.ex 1615 1. Street, NW Bechtel Corporation Washington, D. C. 20036 P. O. Box 2166 Fouston, Texas 77001 Melbert Schwartz, Jr., Esq.

Baker & Botts Mr. E. R. Brooks One Shell Plaza Mr. R. l.. Range Houston, Texas 77002 Central Power and 1.ight Company P. O. Box 212?

Mrs. Peggy Buchorn Corpus Christi, Texas 78403 Executive Director Citizens for Eauitable Utilities, Inc.

Route 1 Box 1684 Brazoria, Texas 77422 J

Houson I.lghting & Power Company South Texas Pro,iect cc:

Regional Administrator, Region IV U. S. Nuclear Regulatory Commission Office of Executive Director for Operations 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011 Mr. lanny Sinkin Counsil for Intervenor Citizens Concerned about Nuclear Power, Inc.

Christic Institute 1324 North Capitol Street Washington, D. C. 20002 Mr. S. Head, Respresentative Houston lighting and Power Company Suite 1309 7910 Woodmont Avenue Bethesda, Maryland 20814

O ENCL.0SURE 1 GENERIC LETTER 83-28 ITEMS STATUS

SUMMARY

G . I. . ITEM STATUS ACTION, COMMENT OR REFERENCE NUMBER 1.1 Open NRC review to be completed.

1.2 Open Additional information required as shown in TER provided as Enclosure 2 herewith.

2.1 Open NRC review to be completed.

2.2 Open NRC review to be completed.

3.1.1 Open NRC review to be completed.

3.1.2 Open NRC review to be completed.

3.1.3 Open NRC review to be completed.

3.2.1 Open NRC review to be completed.

3.2.2 Open NRC review to be completed.

3.2.3 Open NRC review to be completed.

4.1 Closed letter to Goldberg, October 30, 1985 4.2.1 Closed I.etter to Goldberg, October 30, 1985 4.2.2 Closed I.etter to Goldberg, October 30, 1985 4.2.3 Open Pending WOG submittal 4.2.4 Open Pending WOG submittal 4.3 Partially Enclosure 3 provides the SER and Open points out the open item regarding Tech. Specs.

4.4 Not Applies only to B & W plants.

Applicable 4.5.1 Open NRC review to be completed.

4.5.2 Open NRC review to be completed.

4.5.3 Open NRC review to be completed.

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ENCLOSURE 2 SAIC-85/3092 REVIEW OF LICENSEE AND APPLICANT RESPONSES TO NRC GENERIC LETTER 83-28 (Required Actions Based on Generic Implications of Salem ATWS Events), Item 1.2

" POST-TRIP REVIEW: DATA AND INFORMATION CAPABILITIES" FOR SOUTH TEXAS PROJECT, UNITS 1 AND 2 (50-498, 50-499)

October 2, 1985 Technical Evaluation Report Prepared by Science Applications International Corporation 1710 Goodridge Drive McLean, Virginia 22102 Prepared for U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Contract Nc. NRC-03-82-096 pflN g 6! g

FOREWORD This report contains the technical evaluation of the South Texas Project Units 1 and 2 response to Generic Letter 83-28 (Required Actions Based on Generic Implications of Salem ATWS Events), Item 1.2 " Post Trip Review: Data and Information Capabilities." This report supercedes report number SAIC-85/1516 part 4, dated July 10, 1985. This report contains an evaluation of material received by SAIC after July 10, 1985.

For the purposes of this evaluation, the review criteria, presented in part 2 of this report, were divided into five separate categories. These are:

1. The parameters monitored by the sequence of events and the time history recorders,

2. The performance characteristics of the sequence of events recorders,

3. The performance characteristics of the time history recorders,

4. The data output format, and

5. The long-term data retention capability for post-trip review material.

All available responses to Generic Letter 83-28 were evaluated. The plant for which this report is applicable was found to have adequately responded to, and met, categories 2, 3 and 4.

The report describes the specific methods used to determine the cate-gorization of the responses to Generic Letter 83-28. Since this evaluation report was intended to apply to more than one nuclear power plant specifics regarding how each plant met (or failed to meet) the review criteria are not presented. Instead, the evaluation presents a categorization of the responses according to which categories of review criteria are satisfied and which are not. The evaluations are based on specific criteria (Section 2) derived from the requirements as stated in the generic letter.

. 2 TABLE OF CONTENTS Section Page Introduction. . . . . . . . . . . . . . . . . . . . . . . .. . I

1. Background. . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. Review Criteria . . . . . . . . . . . . . . . . . . . . . . . 3

3. Evaluation. . . . . . . . . . . . . . . . . . . . . . . . ... 8 s

4. Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . 9

5. References. . . . . . . . . . . . . . . . . . . . . . . . . . 10 r

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INTRODUCTION i

SAIC has reviewed the utility's response to Generic Letter 83-28, item 1.2 " Post-Trip Review: Data and Information Capability." The response (see references) contained sufficient information to determine that the data and information capabilities at this plant are acceptable in the following areas, o The sequence-of-events recorder (s) performance charac-teristics, e The time history recorder (s) performance characteris-I tics, e The output format of the recorded data.

However, the data and information capabilities, as described in the submittal, either fail to meet the review criteria or provide insufficient information to allow determination of the adequacy of the data and information capabilities in the following areas.

e The parameters monitored by both the sequence-of-events and time history recorders.

l e The long-term data retention, record keeping, capa-bility.

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1. Background On February 25, 1984, both of the scram circuit breakers at ' Unit 1 of >'

the Salem Nuclear Power Plant failed to open upon an automatic reactor trip signal from the reactor protection system. This incident occurred during the plant startup and the reactor was tripped manually by the operatur about 30 seconds after the initiation of the automatic trip signal. The failure of the circuit breakers has been determined to be related to the sticking of the under voltage trip attachment. Prior to tHs incident; on February 22, 1983; at Unit 1 of the Salem Nuclear Power Plant an automatic trip signal was generated based on steam generator low-low level during plant startup.

In this case the reactor was tripped manually by the operator almost coinci-dentally with the automatic trip. At that time, because the utility did not have a requirement for the systematic evaluation of the reactor trip, no investigation was performed to determine whether the reactor was tripped automatically as expected or manually. The utilities' written procedures required only that the causvof the trip be determined and identified the responsible personnel that could authorize a restart if the cause of the trip is known. Following the second trip which clearly indicated the problem with the trip breakers, the question was raised on whether the circuit breakers had functioned properly during the earlier incident. The most useful source of information in this case, namely the sequence of ,

events printout which would have indicated whether the reactor was tripped automatically or manually during the February 22 incident, was not retained after the incident. Thus, no judgment on the proper functioning of the trip system during the earlier incident could be made.

Following these incidents; on February 28, 1983; the NRC Executive Director for Operations (EDO), directed the staff to investigate and report on the generic implications of these occurrences at Unit 1 of the Salem Nuclear Power Plant; The results of the staf f's inquiry into the generic implications of the Salem Unit incidents is repo c', in NUREG-1000, " Generic Implications of ATWS Events at the Salem NucN e h <er Plant." Based on the results of this study, a set of required a t . .t, s e developed and included in Generic Letter 83-23 which was issued on July 8,1983 and sent to all licensees of operating reactors, applicants for operating license, and construction permit holders. The required actions in this generic letter consist of four categories. These are: (1) Post-Trip Review, (2) Equipment 2

Classification and Vender Interface, (3) Post Maintenance Testing, and (4)

Reactor Trip System Reliability Improvements.

The first required action of the generic letter, Post-Trip Review, is the subject of this TER and consists of action item 1.1 " Program Description and Procedure" and action item 1.2 " Data and Information Capability." In the next section the review criteria used to assess the adequacy of the utilities' responses to the requirements of action item 1.2 will be discussed.

2. Review Criteria The intent of the Post Trip Review requirements of Generic Letter 83-28 is to ensure that the licensee has adequate procedures and data and information sources to understand the cause(s) and progression of a reactor trip. This understanding should go beyond a simple identification of the course of the event. It should include the capability to determine the root cause of the reactor trip and to determine whether safety limits have been exceeded and if so to what extent. Sufficient information about the reactor trip event should be available so that a decision on the acceptability of a reactor restart can be made.

The following are the review criteria developed for the requirements of Generic Letter 83-28, action item 1.2:

The equipment that provides the digital sequence of events (SOE) record and the analog time history records of an unscheduled shutdown should pro-vide a reliable source of the necessary information to be used in the post trip review. Each plant variable which is necessary to determine the cause(s) and progression of the event (s) following a plant trip should be monitored by at least one recorder [such as a sequence-of-events recorder or a plant process computer for digital parameters; and strip charts, a plant process computer or analog recorder for analog (time history) variables].

Each device used to record an analog or digital plant variable should be described in suf ficient detail so that a determination can be made as to whether the following performance characteristics are met:

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e Each sequence-of-events recorder should be capable of detecting and recording the sequence of events with a sufficient time discrimination capability to ensure that the time responses asso-ciated with each monitored safety-related system can be ascer-tained, and that a determination can be made as to whether the time response is within acceptable limits based on FSAR Chapter 15 Accident Analyses. The recommer.ded guideline for the SOE time discrimination is approximately 100 msec. If current SOE recorders do not have this time discrimination capability the licensee or applicant should show that the current time discrimi-nation capability is sufficient for an adequate reconstruction of the course of the reactor trip. As a minimum this should include the ability to adequately reconstruct the accident scenarios pre-sented in Chapter 15 of the plant FSAR.

o Each analog time history data recorder should have a sample inter-val small enough so that the incident can be accurately reconstructed following a reactor trip. As a minimum, the licensee or applicant should be able to reconstruct the course of the accident sequences evaluated in the accident analysis of the plant FSAR (Chapter 15). The recommended guideline for the sample interval is 10 sec. If the time history equipment does not meet this guideline, the licensee or applicant should show that the current time history capability is sufficient to accurately recon-struct the accident sequences presented in Chapter 15 of the FSAR.

e To support the post trip analysis of the cause of the trip and the proper functioning of involved safety related equipment, each analog time history data recorder should be capable cf updating and retaining information from approximately five minutes prior to the trip until at least ten minutes after the trip.

e The information gathered by the sequence-of-events and time history data collectors should be stored in a manner that will allow for retrieval and analysis. The data may be retained in either hardcopy (computer printout, strip chart output, etc.) or in an accessible memory (magnetic disc or tape). This information should be presented in a readable and meaningful format, taking 4

into consideration good human factors practices (such as those outlined in NUREG-0700).

e All equipment used to record sequence of events and time history information should be powered from a reliable and non-interruptible power source. The power source used need not be safety related.

The sequence of events and time history recording equipment should monitor sufficient digital and analog parameters, respectively, to assure that the course of the reactor trip can be reconstructed. The parameters monitored should provide sufficient information to determine the root cause of the reactor trip, the progression of the reactor trip, and the response of the plant parameters and systems to the reactor trip. Specifically, all input parameters associated with reactor trips, safety injections and other safety-related systems as well as output parameters sufficient to record the proper functioning of these systems should be recorded for use in the post trip review. The parameters deemed necessary, as a minimum, to perform a post-trip review (one that would determine if the plant remained within its design envelope) are presented on Tables 1.2-1 and 1.2-2. If the appli-cants' or licensees' SOE recorders and time history recorders do not monitor all of the parameters suggested in these tables the applicant or licensee should show that the existing set of monitored parameters are sJfficient to establish that the plant remained within the design envelope for the appro-priate accident conditions; such as those analyzed in Chapter 15 of the plant Safety Analysis Report.

Information gathered during the post trip review is required input for future post trip reviews. Data from all unscheduled shutdowns provides a valuable reference source for the determination of the acceptability of the plant vital parameter and equipment response to future unscheduled shut-downs. It is therefore necessary that information gathered during all post trip reviews be maintained in an accessible manner for the life of the pl a nt .

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1 Table 1.2-1. PWR Parameter List SOE Time History Recorder Recorder Parameter / Signal x Reactor Trip (1) x Safety injection x Containment Isolation (1) x Turbine Trip x Control Rod Position (1) x x Neutron Flux, Power x x Containment Pressure (2) Containment Radiation x Containment Sump Level (1) x x Primary System Pressure (1) x x Primary System Temperature (1) x Pressurizer Level (1) x Reactor Coolant Pump Status (1) x x Primary System Flow (3) Safety Inj.; Flow. Pump / Valve Status x MS!V Position x x Steam Generator Pressure (1) x x Steam Generator Level (1) x x Feedwater Flow (1) x x Steam Flow (3) Auxiliary Feedwater System; Flow.

Pump /Value Status x AC and DC System Status (Bus Voltage) x Diesel Generator Status (Start /Stop, On/Off) x PORV Position (1): Trip parameters (2): Parameter may be monitored by either an SOE or time history recorder.

(3): Acceptable recorder options are: (a) system flow recorded on an SOE recorder, (b) system flow recorded on a time history recorder, or (c) equipment status recorded on an SOE recorder.

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Table 1.2-2. BWR Parameter List SOE Time History Recorder Recorder Parameter / Signal x Reactor Trip x Safety Injectioni x Containment Isolation x Turbine Trip x Control Rod Position x (1) x Neutron Flux, Power x (1) Main Steam Radiation (2) Contlineent(DryWell) Radiation x (1) x Drywell Pressure (Containment Pressure)

(2) Suppression Pool Temperature x (1) x Primary System Pressure x (1) x Primary System Level x MSIV Position x (1) Turbine Stop Valve / Control Valve Position x Turbine Bypass Valve Position x Feedwater Flow x Steam Flow (3) Recirculation; Flow Pump Status x (1) Scram Discharge Level x (1) ,

Condenser Vacuum x AC and DC System Status (Bus Voltage)

(3)(4) Safety Injection; Flow. Pump / Valve Status x Diesel Generator Status (On/Off, Start /Stop)

(1): Trip parameters.

(2): Parameter may be recorded by either an SOE or time history recorder.

(3): Acceptable recorder options are: (a) system flow recorded on an SOE recorder, (b) system flow recorded on a time history recorder, or (c) equipment status recorded on an SOE recorder.

(4): Includes recording of parameters for all applicable systems from the following: HPCI, LPCI, LPCS, IC, RCIC.

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t - 3. Evaluation The parameters identified in part 2 of this report as a part of the

, review criteria are those deemed necessary to perform an adequate post-trip ,

review. The recording of these parameters on equipment that meets the  ;

guidelines of the review criteria will result in a source of information that can be used to determine the cause of the reactor trip and the plant i response to the trip, including the responses of important plant systems. l The parameters identified in this submittal as being recorded by the

[ sequence of events and time history recorders do not correspond to the parameters specified in part 2 of this report.

The information provided in the submittal indicates that the equipment used to monitor the digital and analog parameters meets the minimal requirements set forth in part 2 of this report. The sequence of events and analog time history recorders are powered from a non-interruptable power l

supply. The monitoring characteristics are all within the guidelines of the review criteria.

4 The data and information recorded for use in the post-trip review

should be output in a format that allows for ease of identification and use

) of the data to meet the review criterion that calls for information in a j readable and meani igful format. The information contained in this submittal indicates that this criterion is met.

i The data and information used during a post-trip review should be

retained as part of the plant files. This information could prove useful L during future post-trip reviews. Therefore one criterion presented in part l 2 of this report is that information used during a post-trip review be

! maintained in an accessible manner for the life of the plant. Information

! contained within this submittal does not indicate that this criterion will j be met.

4. Conclusion l

j The information supplied in response to Generic Letter 83-28 indicates i that the current post-trip review data and information capabilities are

adequate in the following areas

.- -.- - - - - -. -_ . . _ , _ ,n_-,---_--,.,,..,,_, , - , - _ , . , , , , , -

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1. The SOE recorders meet the minimum performance characteristics.

2. The time history recorders meet the minimum performance character-istics.

3. The recorded data is output in a readable and meaningful format.

The information supplied in response to Generic l.etter 83-28 does not indicate that the post-trip review data and information capabilities are adequate in the following areas:

1. As described in the submittal, sufficient analog and digital parameters are not recorded for use in the post-trip review.

2. The data retention procedures, as described in the submittal, may not ensure that the information recorded for the post-trip review is maintained in an accessible manner for the life of the plant.

It is possible that the current data and information capabilities at this nuclear power plant are adequate to meet the intent of these review criteria, but were not completely described. Under these circumstances, the licensee should provide an updated, more complete, description to show in more detail the data and information capabilities at this nuclear power plant. If the information provided accurately represents all current data and information capabilties, then the licensee should either show that the current post trip review data and information capabilities are adequate to meet the intent of the criteria in part 2 of this report, or detail future modifications that would enable the licensee to meet the intent of the evaluation criteria.

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REFERENCES NRC Generic Letter 83-28. " Letter to all licensees of operating reactors, applicants for operating license, and holders of construction permits regarding Required Actions Based on Generic Implications of Salem ATWS Events." July 8, 1983.

NUREG-1000, Generic Implications of ATWS Events at the Salem Nuclear Power Plant April 1983.

Letter from J.H. Goldberg, Houston Lighting and Power, to D.G.

Eisenhut, NRC, dated November 3,1983, Accession Number 8311210275 in response to Generic Letter 83-28 of July 8, 1983, with attachment.

Letter from J.G. Dewease, Houston Lighting & Power, to H.L. Thompson, NRC, dated February 26, 1985 Accession Number 8503050319 providing partial response to Generic Letter 83-28.

Letter from J.H. Goldberg, Houston Lighting and Power, to H.L. Thompson USNRC, dated June 28, 1985, Accession Number 8507150281, providing additional response to Generic Letter 83-28 of July 8,1983, for South Texas Project. Units 1 and 2.

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, Oc e amur f* TetuN South Texas Project

1. Parameters recorded: Unsatisfactory No parameter lists were provided. However basis described for the selection of parameters would appear to include most, if not all, of the desirable parameters.

2. SOE recorders performance characteristics: Satis factory Plant computer: 4 msec time discrimination with a non Class 1E uninterruptible power supply

3. Time history recorders performance characteristics: Satisfactory Plant r.omputer: Data sampled at 10 secs intervals for the period from ten minutes prior to the trip to ten minutes after the trip ERFDADS: Data sampled at 0.5 sec intervals from the time of the trip until 10 min post trip

4. Data output format: Satisfactory SOE data output includes time of event, sensor ID, and parameter / event descriptor Analog data output includes time and parameter name and value

5. Data retention capability: Unsatisfactory The length of time the data is retained is not specified.

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