ML17158B899

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Summary of 960125 Meeting W/Util in Allentown,Pa Re Safe Shutdown Analysis Issues Re Rev 4 of Fire Protection Review Rept for Plant & Deviation Request Re MOV Hot Shorts.List of Attendees Encl
ML17158B899
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 12/23/1996
From: Poslusny C
NRC (Affiliation Not Assigned)
To:
NRC (Affiliation Not Assigned)
References
NUDOCS 9612310121
Download: ML17158B899 (34)


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LICENSEE:

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 23, 1996 Pennsylvania Power and Light Company (PP&L) g, - 7,S 7/3<8'ACILITY:

Susquehanna Steam Electric Station (SSES),

Units 1 and 2

SUBJECT:

SUMMARY

OF JANUARY 25, 1996 MEETING TO DISCUSS INSTALLATION OF ON-SITE STORAGE FACILITY FOR SPENT FUEL AT SSES, UNITS 1

AND 2 On January 25,

1996, NRC and PP&L staff met in Allentown, Pennsylvania, to discuss Safe Shutdown Analysis (SSA) issues related to Revision 4 of the Fire Protection Review Report (FPRR) for Susquehanna Steam Electric Station (SSES) and a deviation request related to motor-operated valve hot shorts.

Enclosure 1 is a list of those who attended the meeting, Enclosure 2 is the agenda that was followed based on NRC questions about items included in the FPRR and Enclosure 3 is the set of slides presented by PP&L staff which included some additional items for discussion.

The following are the highlights of the items discussed during the meeting.

1.

Status of the FPRR PP&L indicated that revisions subsequent to ¹4 did not include significant changes to the SSA.

It was therefore agreed upon that the open items that the staff was pursuing would only deal with the adequacy of the SSA for SSES in Revision 4 of the FPRR.

2.

Alternative Shutdown Capability

~

PP&L clarified that Safe. Shutdown (SSD)

Path 2 relies upon Path 2

components and no other path's support systems to achieve the desired plant condition.

For Path 2,

PPSL indicated that the reactor core isolation cooling (RCIC) system can take suction from either the condensate storage tank (CST) or the suppression pool (SP).

The suction can be switched at any time manually and is switched to the SP when the CST has been drained down to a level controlled administratively.

In addition, there is an administrative control which requires switching to the CST from the SP when its temperature exceeds 90 degrees F.

PP&L indicated that regarding the CST and its associated level instrumentation, the operators rely on the local readouts and the procedures specify that these readouts must be taken at appropriate times.

It was noted also that the procedures that require taking CST local level data were not taken credit for in the SSD methodology but that PP&L would consider adding this to its methodology.

~ The loss of offsite power item in the agenda was deleted from the discussion because the information was apparently included in the previous submittals.

pF 'DI

'6i23i012i 96i223 PDR ADOCK 05000387 F

PDR

~ Repair activities for achieving hot shutdown conditions PP&L indicated that the procedures N-100-009 and ON-200-009 instruct operators to install temporary reactor level indication to enhance level monitoring during cold shutdown, but not during hot shutdown conditions.

~ Drywell Temperature and Pressure Monitoring PP&L indicated that the operators can obtain remote shutdown panel readouts of drywell temperature and pressure but that this is not relied upon in the Susquehanna FPRR.

These readouts are available for EOPs.

~

SSA supporting calculations PP&L indicated that the 17 calculations supporting the SSA were available for NRC staff audit.

The staff indicated that they would look at the files and might perform some limited reviews to support the safety evaluation.

~ Alternative Shutdown Capability Modifications PP&L stated that most modifications performed during the 1987-1988 time frame had not been included in the FPRR but would consider adding references to the mods in the FPRR.

3.

Associated Circuits

~ Spurious Valve Actuations As included in the set of slides, PP&L has determined that existing

analysis, system design characteristics, and existing procedures ensure that 10 CFR Part 50, Appendix R, Section III.G.2, requirements are met relative to spurious actuation of redundant valves.

Specifically, regarding concerns raised by the Brookhaven National Laboratories (BNL) engineer.who reviewed the previous PP&L submittal, PP&L determined that a single fire could not cause both suppression pool cleanup valves to open.

In addition, it was noted that the containment instrument gas valves which were identified by the staff as being vulnerable to fire

damage, are not needed for Appendix R SSD and will be deleted from the FPRR.

PP&L presented a summary of the definitions, criteria for its evaluation of the issue, examples of valves evaluated and support for its conclusion that the plant can meet the specific regulation with minimal modifications.

. ~ Regarding Deviation Request 41, PP&L indicated that in its analysis of the effects of hot shorts in the control room caused by fire had not been postulated for a number of deterministic and probabilistic reasons.

The staff indicated that it disagreed with PP8L's position and suggested that it consider the work that Comanche Peak had done on the issue.

This work included a detailed evaluation of valve circuitry that could be affected and a systematic screening of the valves and systems such that a smaller number of circuits would ultimately require additional protection to ensure that sufficient capability existed for safe shutdown after a control room fire.

PPLL agreed to reconsider its position and provided a revised submittal to address agreements reached during the meeting.

/s/

Chester

Poslusny, Senior. Project Manager Project Directorate I-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket Nos. 50-387/388

Enclosures:

1.

Meeting Attendees List 2.

Meeting Agenda 3.

Licensee's Handouts cc w/encls:

See next page DISTRIBUTION: w/Enclosures 1 and 2

  • w/Enclosure 3

HARD COPY

  • Docket File
  • PUBLIC
  • WPasciak, RGN-I E-NAIL WRussell/FMiraglia RZimmerman SVarga JZwolinski JStolz
  • CPoslusny MO'Brien EJordan (JKR)

PMadden

WRuland, RGN-I WDean OFFICE PDI-P P I-2 NAME CPoslusny:rb S

lz 7

l>96 l~ i~96 DATE

/

96 OFFICIAL RECORD COPY OCUMENT NAME:

SU1-25.MTS

~ Regarding Deviation Request 41, PP&L indicated that in its analysis of the effects of hot shorts in the control room caused by fire had not been postulated for a number of deterministic and probabilistic reasons.

The staff indicated that it disagreed with PP&L's position and suggested that it consider the work that Comanche Peak had done on the issue.

This work included a detailed evaluation of valve circuitry that could be affected and a systematic screening of the valves and systems such that a smaller number of circuits would ultimately require additional protection to ensure that sufficient capability existed for safe shutdown after a control room fire.

PP&L agreed to reconsider its position and provided a revised submittal to address agreements reached during the meet'ng.

Docket Nos. 50-387/388 Chester Posl sny, Senior Project Manager Project Directorate I-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation

Enclosures:

I.

Meeting Attendees List 2.

Meeting Agenda 3.

Licensee's Handouts cc w/encls:

See next page

Pennsylvania Power

& Light Company Susquehanna Steam Electric Station, Units 1

& 2 CC:

Jay Silberg, Esq.

Shaw,'ittman, Potts

& Trowbridge 2300 N Street N.W.

Washington, D.C.

20037 Bryan A. Snapp, Esq.

Assistant Corporate Counsel Pennsylvania Power

& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Mr. J.

M. Kenny Licensing Group Supervisor Pennsylvania Power

& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Mr. K. Jenison Senior Resident Inspector U. S. Nuclear Regulatory Commission P.O.

Box 35 Berwick, Pennsylvania 18603-0035 Mr. William P. Dornsife, Director Bureau of Radiation Protection Pennsylvania Department of Environmental Resources P. 0.

Box 8469 Harrisburg, Pennsylvania 17105-8469 Mr. Jesse C. Tilton, III Allegheny Elec. Cooperative, Inc.

212 Locust Street P.O.

Box 1266 Harrisburg, Pennsylvania 17108-1266 Chairman Board of Supervisors 738 East Third Street

Berwick, PA 18603 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, Pennsylvania 19406 Mr, Harold G. Stanley Superintendent of Plant Susquehanna Steam Electric Station Pennsylvania Power and Light Company Box 467 Berwick, Pennsylvania 18603 Mr. Herbert D. Woodeshick Special Office of the President Pennsylvania Power and Light Company Rural Route 1,

Box 1797 Berwick, Pennsylvania 18603 George T. Jones Manager-Engineering Pennsylvania Power and Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Mr. Robert G.

Byram Senior Vice President-Nuclear Pennsylvania Power

& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Dr. Judith Johnsrud National Energy Committee Sierra Club 433 Orlando Avenue State College, PA 16803

MEETING ATTENDEES LIST APPENDIX R

"FIRE PROTECTION" JANUARY 25 1996 NAME C. Poslusny P.

Madden W. Ruland J.

Kenny E. Jebsen S. Davis W. Williams T.

Gorman G. Hiller B. Maiers K. Sullivan ORGANIZATION NRC/NRR NRC/NRR NRC/Region I PPKL PPRL PPKL PPKL PPKL PPKL PADEP-BRP BNL ENCLOSURE 1=

DRAFI'GENDA Fire Protection Program Review Meeting Susquehanna Steam Electric Station Pennsylvania Power and Light Headquarters Allentown, Pennsylvania January 25, 1996 The review of Revision 4 of the Pennsylvania Power and Light (PP&L) Fire Protection Review Report (FPRR), determined that the FPRR does not contain sufficiently detailed information necessary to complete a comprehensive review of the post fire safe shutdown capability and alternative shutdown system design developed by PP&L for the Susquehanna Steam Electric Station. The need for PP&L to provide more detailed information and additional supporting calculations was addressed as part of our request for additional information (RAI), dated February 3, 1995, and during the August 29, 1995 meeting at NRC headquarters, with representatives of the licensee.

By letter dated May 22, 1995, PP&L provided its response to the February 3, 1995 RAI, and, subsequent to the August 29 meeting, forwarded a copy of PP&L Calculation EC-013-0859, "Appendix R Safe Shutdown Analysis for a Control Room Fire", Rev.1, dated August 28, 1995 to BNL for review.

The BNL review of the more detailed information contained in these submittals identified several potentially significant concerns with regard to (a) the assumptions used by the licensee during its performance of its Safe Shutdown Analysis and (2) the completeness of information contained in Revision 4 of the FPRR Specific topics which should be included in the licensee's discussion are outlined below:

DISCUSSION TOPICS

1. Status of Fire Protection Review Report

- Most current revision

- Explanation of Changes from Rev 4

- Differences between Revision 4 and 5

2. Alternative Shutdown CapabBity Provide a detailed discussion of the alternative shutdown capability, that, as a minimum addresses each of the following:

The Alternative Shutdown Path (Path 2) is based on an evacuation of the main control room, and shutting down the plant from the respective Remote Shutdown Panel of each unit together with any required local operator actions.

To achieve alternative safe shutdown RCIC and associated support systems,

together with Path 1 or Path 3 components are used.

From the above it is not clear whether Path 2 uses both Path 1 and Path3 components or just one Path.

Please clarify.

~

For Path 2 reactor coolant makeup is provided by RCIC and RHR injection taking suction from the Condensate Storage Tank.

At what time is the suction path for the RCIC pump transferred from the CST to the suppression pool'I The CST and its associated level instrumentation do not appear to be identified as components requir'ed for safe shutdown.

Please explain.

~

It appears that a Loss of Offsite Power voluntarily imposed to ensure closure of the MSIVs.

~

PP&L letter dated May 22, 1995, states that no repair activities are required to achieve hot shu'tdown conditions.

Notwithstanding this statement, two procedures, ON-100-009 and ON-200-009, "Control Room Evacuation," each Revision 3, for Units 1 and 2 respectively, in Step 4.3.4, instruct the plant operators to:

"NOTIFYI&C to install:

a.

Temporary (reactor) level indication in accordance with IC-180-004 (IC-280-004) Reactor Range Level Measurement at Rack 1C005 PC005),

LT-B21-1N027 (LT-B21-2N027).

b.

Temporary reactor coolant temperature indication in accordance with 1C-The actions described above appear to constitute Hot Shutdown Repair activities.

As noted in NRC Information Notice 84-09, the staff considers reactor level indication as part of the minimum required instrumentation for alternative safe shutdown for a BWR. None of the approved or pending deviation requests appear to relate to a request to seek approval for a Hot Shutdown'repair to install temporary reactor level instrumentation. Please explain why step a, which is to be performed immediately after control,has been established at the Remote Shutdown Panels, (i.e., in the early stages of Hot Shutdown, does not constitute a repair during Hot Shutdown).

please explain.

Since RCIC is the designated shutdown method for Path 2, it appears that it is necessary to monitor Drywell pressure and temperature to determine whether depressurization of the RPV is required.

Please explain why Drywell Pressure and Temperature are not being monitored.

Section 6 of the Appendix R Analysis for a Control Room Fire identifies 17 calculations performed by PP&L in support of its Safe Shutdown Analysis.

These calcblations are not referenced in the FPRR.

Due to the FPRR's lack of specific hkhnical detail, it is requested that these supporting documents be made available for review.

Section 7.3 of the Control Room Analysis describes a number of modifications that were necessary to resolve deficiencies in the alternative shutdown capability.

Specific examples include:

~

Installation of a new alternative shutdown control panel for Control Structure HVAC.

~

Installation of new temperature switches to support EDG and ESW HVAC requirements Rev. 4 of th Isolation of EDG control circuits from fire damage e FPRR does not address these modifications. Please explain.

3.

Associated Circuits By letter dated May 22, 1995, (response to a February 1995 RAI) PP&L identified several examples where redundant valves may be subject to spurious operations (i.e., undesirable change in position) as a result of a single hot short on their respective control circuits.

Although the control circuits of the redundant valves may be damaged by single fire, and their fire-induced spurious operation would adversely affect the safe shutdown capability, PP&L states in the response that based on its interpretation of NRC Generic Letter 86-10, it had assumed that only one of the valves would spuriously actuate.

This response was discussed further during the August 29 meeting at NRR.

Based on the above PP&L position, it is not clear how compliance with Section III.Gof Appendix R could be demonstrated ifredundant components were not adequately protected from fire damage.

Please explain.

Section 5.2 of the PP&L Control Room Analysis states the following: "Each component and associated cable identified in Section 5.I was reviewed to determine whether proper isolation ofthe cable exists. Ifisolation exists, component operability is assured outside the Control Room and thusno further review was performed. " From this statement, it appears that ifa component required to achieve alternative shutdown from outside the Control Room was provided with electrical isolation capability (i.e., actuation of an isolation/transfer switch), it was assumed that no further review was necessary since fire damage would not occur prior to transfer. Such an assumption, however, appears to be contrary to NRC staff positions contained in Generic

Letter 86-10 (Response to Question 5.3.10), Information Notice 85-09 (potential for fuse failure prior to transfer), and Information Notice 92-18 (potential for spurious Motor Operated Valve operations prior to transfer).

Please explain.

~

Section 4.4.3 of the PP&L Control Room Analysis states that equipment damage (emphasis added) due to hot shorts was not postulated based on the low probability of this condition affecting safe shutdown.

This position appears to be contradictory to NRC concerns identified in IN 92-18.

C:(WP6DOCS)SSD WORK(AGND SSE.MTG

INTRODUCTION

- RESPONSES TO NRC QUESTIONS

~ THERMO-LAGRESOLUTION PLAN

~ FIRE PROT. SUBMITTALSTATUS ENCLOSURE 3

Have an Exchange of Information Reach a Common Level of'nderstanding on the Following Issues:

~ PPEL's Responses to NRC Questions

~ Criteria for Evaluating Spurious Operations

~ PPEL's Approach to Resolving the Thermo-Lag Issue

~ Status OfPPEL Fire Prof Su.bmittals

Plant Layout (Appendix R Areas)

Safe Shutdown History

~ Original Fire Zone minoritylmajority approach

~ 1985 Audit Fir e Area Approach 3 Safe Shutdown Paths

Alternate Shutdown Capability

~ Designated as Safe Shutdown Path 2 Rx SCRAM RCIC with RHR Suppression Pool Cooling RHR Shutdown Cooling

~ ON 1/2-00 00-9, Control Room Evacuation Shutdown from the Remote Shutdown Panel Event Based Procedure Us ed forFires and other situations

2. Status ofFPRR

~ 2. Alternate Shutdown Capability a 3. Associated Circuits

SUPPRESSION CLEAN-UP VALVES

~ For all fires where shutdownis governed by the requirements ofApp R Section III.6.2, a siri gle fire cannot cause both valves to open.

~ Cables that could cause this are routed togetheriri only one fire area U.1: one set ofcables is protected; U2: uses protection plus a deviation request

CONTAINMENTINST. GAS VALVES

~

~ Va/ves have been deterrriined nof to be required forAppendix R Safe Shutdown

Current Understanding Derived from:

~ Review of the Regulations/Guidance

~ Review of the Advanced Reactor Designs

~ August 29, 1995 NRC Meeting

~ Review of the "Hot Short" Mechanisms

~ Review of Cable Failure Probability Data

(

CRITERIA-SCOPE: (/II.G.2)

~ Applies to associated circuits that could prevent the operation or cause the maloperation of the Redundant Train used to achieve and maintain Hot Shutdown.

T-P T

I PER.

RITERI DEFINITIION:

~ prevent the operation or cause the maloperation cables for components whose spurious operation could resultin eitherinventory loss from the Reactor Vessel, or flowdiversion or flowblockage in the inventory make up -or decay heat removal systems.

Criteria to determine ifa component's

~

spurious operation is credible: (5.3. 7)

~ For Hi/Lopressure inferface components, 3 ph-ase hot shorts on AC circuits and two hot shorts of fhe proper polarity without grounding on ungrounded DC circuits must be considered.

~ For all ofher componenfs, these condifions which require the occurrence ofmulfiple hot shortslcomponents are not considered

T-P R.

Number ofsimultaneous spuriou operations that must be considered f each fire:

~

ilLopressureinterfaces must c id where affected by the same fire, th simultaneous spurious operation ofb th valvesin the same line.

~ AIIOthers mu-st address all spu perations, but on a one-at-a-time b (i e N.on.-simultaneous)

)

4 0\\

I'I I P R.

PER.

RITERI Definition:

~ Simulfaneous:

. The "hot shorts" exist af the same time l

~ Non-simulfaneous:

The "hot shorts" do nof exisf at fhe same time, but the residual effects offhe "hot short" can exist for fhe durafion of fhe fire or until correcfed..

T I'ER.

TERI DEFINITIION:

~ Hi/Lo Pressure Inferface Valve: (81-12)

Valve whose spurious opening could resultin a loss ofReactor Pressure Vessel inventory and, due to the lower pressure rating on fhe downstream piping, an interfacing LOCA.

T-P R.

PER.

TE Definition:

~ Address (examples)

P.rovide Fire Barrier or Wrap Reroute or relocate circuit/component Provide a Procedural Action (e g O.e.po-wer)

Perform an analysis to identify other equipment that can perform the function offhe spuriously operated component or that will prevent the spuriously operated component from affecting the safe shutdown path

T P

R.

PER.

TEM Criteria Clarification:

~ ln performing the analysis, the component selected as the other equipment cannot be a component that has the potential to spuriously operate due to the same fire,if the residual affect ofthe hot short leaves the primary componentin fhe undesired state.

Examples:

~ Two MOV'sin series fo prevenf flow diversion

~ Two SOYsin series to prevent flow dlvelsion

~ An open min. flow valve fhat prevents a spurious pump start from "dead he-ading" a pump required to support safe shufdown.

TEM Examples:

0

~ Discuss each example for:

only 1 component affectedin fire area both components affectedin fire area allexamples and all components affectedin the ~

fire area

Deviation Request 42 e Revised Deviation Request 4, 29, 40

~ Future Deviation Requests

~ Cross Fire Zone Interaction Criteria

~ Intra Fire-Zone Specific Evaluations

Acceptance of Tech. Spec. Change for Removing Fire Protection from Tech.

Spec's.

~ Plans to Remove Fire Protection from FSAR by Reference to FPRR

~ Approval of FPRR

~ Approval of Deviation Reqoest 41

Deviation Request 41: PLA-3980 dated June 21, 1993

~ Clarificafion: PLA-4341 dated August 2, 7995

~ Revised Deviation Request 41

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