IR 05000352/1985048

Insp Rept 50-352/85-48 on 851216-860103.No Violations Noted. Major Areas Inspected:Startup Test Program During Test Condition 6,including Results Evaluation,Plateau Review, Qa/Qc Interfaces & Independent Measurements

ML20140E223
Person / Time
Site:	Limerick
Issue date:	01/28/1986
From:	Eselgroth P, Florek D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20140E209	List: IR 05000352/1985048 ML20140E205
References
50-352-85-48, NUDOCS 8602030206
Download: ML20140E223 (10)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /85-48 Docket N License N NPF-39 Priority --

Category C Licensee: Philadelphia Electric Company 2301 Market Street Philadelphia, Pennsylvania 19101 j Facility Name: Limerick Nuclear Generating Station Inspection At: Limerick, Pennsylvania Inspection Conducted: December 16, 1985 - January 3, 1986 Inspector . . /~ 28' 86 0.~J. Flor , Lead Reactor Engineer date TPS, 08, ivision of Reactor Safety j

Approved by: _- [' 2 b M P. W. Eselgrg h, Section Chief, date Test Progr6fus, 08, Division of Reactor Safety Inspection Summary: Inspection on December 16, 1985-January 3, 1986 (Inspection Report 50-352/85-48).

Areas Inspected: Routine unannounced inspection of the startup test program ,

during test condition 6 including startup test witnessing, startup test results evaluation, plateau review, QA/QC interfaces, independent measurements and tours of the facility. The inspection involved 61 hours7.060185e-4 days <br />0.0169 hours <br />1.008598e-4 weeks <br />2.32105e-5 months <br /> onsite by one region based inspecto Results: No violations were identifie Note: For acronyms not defined refer to NUREG " Handbook of Acronyms and ;

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Initialisms" B602030206 860129 PDR ADOCK 05000352 G PDR

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DETAILS 1.0 Persons Contacted Philadelphia Electric Company (PECO) and contractors D. Atkinson, Lead Startup Test Coordinator

• J. Doering, Operations Engineer

• P. Duca, Technical Engineer-

• C. Endriss, Regulatory Engineer P. Fleckser, Startup Test Scheduler

• J. Franz, Superintendent of Operations

• J. Isaacs, NSSS Test Supervisor A. Jenkins, Startup Test Program Supervisor

• G. Leitch, Plant Manager

• J. McElwain, QA Auditor

• J. Rupert, QA Site Supervisor

• J. Spenser, Superintendent of Plant Services

• V. Warren, Test Engineer U.S. Nuclear Regulatory Commission E. Kelly, Senior Resident Inspector

• Denotes those present at the exit meeting on January 3, 1986.

The inspector also contacted other licensee and contractor personnel in the course of the inspection including reactor operators, startup engineers and technical staf .0 Startup Program References

Regulatory Guide 1.68, Revision 2, " Initial Test Program for Water-Cooled Nuclear Power Reactors"

• ANSI 18.7 - 1976, " Administrative Controls and Quality Assurance for the Operational Phase of Nuclear Power Plants"

Limerick Generating Station (LGS) Technical Specification

LSG Final Safety Analysis Report

LGS Safety Evaluation Report

Specification NEB 0 23A1918, Revision 0, " Limerick 1 and 2 Startup Test Specification"

• LGS Startup Program Schedule

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• Administrative Procedure A-200, "Startup Test Procedure Format and Content"

• Administrative Procedure A-201, "Startup Test Procedure Control"

• Administrative Procedure A-202, "Startup Test Implementation"

• Administrative Procedure A-203, "Startup Test Program Personnel Training and Qualification" 2.1 Test Witnessing Scope The inspector witnessed portions of the preparation, conduct and recovery of the following startup test STP-25.3 " Full Main Steam Isolation Valve (MSIV) Isolation" STP-27.4 " Turbine Trip at TC-6" The tests were witnessed for the attributes identified in inspection report 50-352/84-72 in section Disccssion For the activities witnessed, except for the use of HPCI to inject into the vessel during the turbine trip test as described below, the applicable attributes were found to be satisfied. A summary of each activity witnessed is discussed belo FULL MSIV ISOLATION On December 18, 1985 the licensee conducted STP-25-3, " Full MSIV Isolation." This test was originally scheduled to be performed at a later date, but the licensee was experiencing higher than desired bus'

duct temperatures in the main electrical generator and decided to perform STP-25.3 to shut down to replace portions of the bus duc The inspector observed the licensee pre and post test activities as well as conduct of the test itself. The licensee conducted several pre-test meetings in preparation for the test where expected results as well as potential problems were discussed. The licensee conducted a test briefing just prior to the tes In addition, extra opera-tional personnel were on-shift to respond to unexpected event Senior plant management as well as off-duty superintendents were in '

the control room to observe the plant response. QA/QC personnel also t witnessed the tes ,

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Just prior to the test, the plant power level was raised to 90%

power and a demand for MSIV closure was caused by simulating a valid low steam line pressure while the plant was in the RUN mode. MSIV closure and reactor scram occurred at approximately 7:39 p.m. The minimum reactor water level reached was just barely -38 inches which initiated some of the actions that occur when -38 inches is reache The recirculation pumps tripped and high pressure coolant injection (HPCI) started. Due to the water level recovery shortly after -38 inches was reached, HPCI started but did not inject into the vesse The operator manually placed HPCI in the CST to CST mode to assist in the pressure control. The low level reached was not quite low enough for RCIC to receive an initiation signal so this system was manually initiated by the operator. Maximum reactor precsure im-mediately after the trip was 1038 psi. No SRV's were required to operat No unacceptable conditions were observe The licensee was aware that the power level at which this test was performed was lower than planned. The licensee is performing ana-lysis to extrapolate expected plant performance at 100% power. The adequacy of this evaluation will be assessed in a subsequent inspec-tion during test results evaluatio Turbine Trip On January 2, 1986, the licensee conducted the STP-27.4 turbine trip from approximately 99% power. The test was performed earlier than planned to utilize the startup test to shut the reactor down due to a steam leak that had occurred downstream of one of the main turbine cross around relief valves when the valve inadvertently opened prior to the test with the plant at approximately 100% power. The leak location was such that when the steam leak was isolated by lowering power to close the relief valve, condenser vacuum could not be main-tained. Inspector inquiry of the consequences of the steam leak iden-tified that the licensee had evaluated the radiological consequences of the steam leakage which posed no immediate concern, however, plant shutdown for repair would be required. Since the plant required shut-down for repairs, the licensee conducted STP-27.4. The licensee had approximately 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> for test preparations. Due to the prior licensee planning activities in the startup program, this time period was more than adequate for test preparation. Since the licensee anticipated loss of condenser vacuum following the turbine trip, with the result-ant loss of turbine bypass valve capability, feedwater pumps and main steam isolation valve (MSIV) closure, the licensee planned to maximize plant depressurization using the main condenser as a heat sink. The inspector witnessed several test planning meetings as well as the briefing just prior to the test. The operators were instructed to let the plant automatically control itself for the first three minutes

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1 unless automatic actions failed, as required per the startup pro-cedur In addition the licensee called in extra operations person-nel in anticipation of any plant problems. Senior licensee manage-ment as well as QA/QC personnel witnessed the test activitie At 8:54 p.m. on January 2,1986 the licensee tripped the main turbine which caused the reactor te scram. The water level reached a minimum

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of +5 inches immediately following the scram and reactor pressure peaked at approximately 1000 psi. No SRV lifted as expecte The feedwater pumps automatically tripped when reactor water level reached +54 inches. This resulted in a failure of one of the level

, 2 test acceptance criteria and would require preparation of a test

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exception report. After three minutes had elapsed the mode switch was placed in shutdown and normal operator actions were permitte The turbine bypass valves were used to control reactor pressure. The l

licensee was reducing reactor pressure to maximize heat removal by t the condenser.

j As water inventory was being depleted, the operators attempted to re-

start the feedwater pump but had some difficulty and started reactor core isolation cooling (RCIC). Condenser vacuum was being lost fol-lowing the turbine trip and caused closure of the (MSIV) at 9

17 p.m.

1 Following closure of the MSIV, reactor pressure was approximately 650 psig and began increasing and water level was being controlled by RCIC.

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The licensee manually started high pressure coolant injection (HPCI)

at approximately 9.20 p.m. and utilized HPCI to inject water into the

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reactor vessel. At +54 inches both RCIC and HPCI tripped at annroxi-i mately 9.23 p.m. This action resulted ir loss of a convenient pres-sure control operation of HPCI in the CSf to CST flowpath and RCIC

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maintaining reactor water level contro To recover from this situa-tion the licensee attempted to maximize letdown to the hotwell through reactor water cleanup (RWCU) and minimize water addition via the con-trol rod drive cooling water to allow water level to drop below +54

.t inches. Since reactor pressure was increasing and water level could not be lowered fast enough to restart HPCI, an SRV was manually opened to control pressure. This use of water inventory was suffi-  !

cient to permit manual start of HPCI in the CST to CST flow path to control pressure and RCIC was used to control leve The inspector contacted the Operations Engineer following the test to 1 determine if there was anything that he observed during the test and subsequent recovery actions that could be improved upon and fed back to the remaining operator staf The Operations Engineer discussed several lessons learned and plans for feedback to the operator requa-1 training. The one item that represented an inspector observation, j as well, was the operator initial use of HPCI to restore water level with the MSIV closed. The use of HPCI for this purpose appeared un-necessary at this time and resulted in the plant being in a safe but

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l 1 not most desirable position. The Operations Engineer discussed his l

plans which provided the feedback to the operations staff on the use of HPCI in this type of situation. Based on the Operation Engineer's observations and plans, the inspector had no further concerns at this time regarding personnel performance and feedback to operations.

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Findings No violations were noted.-

2.2 Test Results Evaluation --

Scope The startup tests listed in the discussion section below were reviewed for the attributes identified in inspection report 50-352/84-70 section Discussion The test results reviewed met the applicable attributes referenced above. However, the test results reviewed have not completed the management review cycle and were in various stages of revie Verification of complete review will be assessed in subsequent inspectio Tests performed during TC-4 STP-221 " Pressure Regulator Response - Control Valve Operation",

Revision 1, test implemented November 30, 1985 For 3 psi and 5.5 step change in pressure setpoints, no unacceptable oscillations were note STP-22.3 " Pressure Regulator Response - Bypass Valve Operation,"

Revision 1, test implemented November 30, 1985 For 3 psi and 5.5 step changes in pressure setpoints, no unaccept-able oscillations were note '

Tests performed during TC-5 STP-22.1 " Pressure Regulator Response - Control Valve Operation,"

Revision 1, test implemented November 26, 198 For 3 and 5.5 step changes, no unacceptable oscillations were noted when this test was performed with the reactor at 49%

STP-22.3 " Pressure Regulator Response - Bypass Valve Operation",

Revision 1, test implemented November 27, 198 _ - _ _ - - _ _ _ _ _ _ _ _ _

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For 3, 6 and 7 psi step changes at 69% reactor power, no unacceptable oscillations were note Tests performed at TC-6 STP-12.3 "High Power APRM Calibration," Revision 1, test implemented December 28, 1985 APRM's were adjusted to read equal to or greater than actual powe ' STP-24.1 "Stop Valve Testing", Revision 0, test iinplemented December 31, 1985 The test was performed at 91.8% power. Margins to scram were acceptable. The extrapolated maximum power to perform this test with minimum acceptable margins to scram sas 94%.

STP-24.2 " Control Valve Testing," Revision 0, test implemented December 31, 1985 The test was performed at 89.2% power. Margins to scram were acceptable. The extrapolated maximum power to perform this test with minimum acceptable margins to scram was 93%.

STP-24.2 " Control Valve Testing" Revision 0, test implemented December 28, 1985 The test was performed at 78% power. Adequate scram margins were demonstrate STP-33.1 " Main Steam Piping (Inside Drywell) Steady State Vibration", Revision 0, test implemented December 27, 198 The test was performed at 100% steam flow. Vibration levels were acceptabl STP-33.2" Recirculation Piping Steady State," Revision 1, test implemented December 27, 1985 The test was performed at 100% recirculation flo Vibration levels were acceptabl STP-25.3 " Full MSIV Isolation", Revision 1, test implemented December 18, 1985 The test was performed with the reactor at 90.2% powe In a future inspection, the inspector will review the licensee evaluation to justify the test performance at the power level actually performed versus the planned power leve _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .

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Key trip sequence of events are listed below hours sec 1939 23 MSIV steam line trip signal 23 Reactor scram signal 29 Recirc pump trip signal i 1940 28 Reactor feedwater pump trip 1941 58 Turbine generator trip The minimum water level and pressure reached at approximately 5 seconds was -38 inches and 1038 psig. The MSIV stroke times satisfied the test criteria of between 3-5 seconds and ranged from 3.0 - 4.13 second The acceptance criteria for pressure increase and heat flux increase were satisfie The inspector reviewed the sequence of events log against the plant performance and verified the reactor protection system (RPS) actua-tions occurred when demanded due to water level, reactor pressure, and MSIV closure. The inspector also reviewed redundant reactivity control system (RRCS) performance and verified that the alternate rod injection logic was actuated and the recircu!ation pumps tripped 10 seconds after a valid low water signal was received. The inspector also reviewed GP-18 " Scram Review Procedure, " Revision 0 dated October 26, 1984 and noted that post scram activities did not include an assessment of the RRCS performance. The licensee had also recognized this prior to this inspection and had a revision in the change cycle to correc Findings

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No violations were noted.

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2.3 Plateau Review Scope

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The inspector witnessed portions of the PORC Meeting 85-126 on December 16, 1985 to ascertain whether the licensee is performing an adequate evaluation of test results, test changes, and test exceptions and following their procedures for review, evaluation

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and acceptance of test results, test changes and test exception .

l Discussion Several test change notices were reviewed as well as a proposed -

revision to STP-27.4. In addition, the PORC reviewed a licensing [

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amendment request to extend the interval for certain containment isolation valve local leak rate tests. No unacceptable conditions were note . . _ _- - -._ .. - . _. __ _ . . _ , .-. . - .

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3.0 Local Leak Rate Testing The inspector witnessed portions of the performance of ST-1-LLR-701-1 "D Core Spray Pump Suction", Revision 3 on December 17, 1985 to assess whether the local leak rate test was being performed in accordance with the proce-dure. The inspector witness portion of the activities associated with set-ting up the test and test performance. The inspector observed coordination and permission to perform the test with the operation personnel. The in-spector accompanied the test engineer and operating personnel during the setting up of the test boundary in accordance with the procedure and apply-ing the appropriate tags following' operation of the valves. The test engi-neer was permitted by operations to operate certain test valves in accord-ance with the procedure but key process system valves required operations personnel to operate. The inspector witnessed the test engineer calcula-tions to determine the test pressure to correct for the location of the test surge tank assembly. Portions of the actual test were witnesse No unacceptable conditions were note .0 QA/QC Interfaces The licensee continues to maintain a high degree of QA/QC involvement in the startup program. The inspector routinely observed QC conducting surveillances of startup tests. QA personnel are also conducting contin-uing audits of overall startup program implementation. The audit inter-vals are keyed to the test conditions. The inspector routinely observed QA audit personnel witnessing conduct of startup tests, reviewing licensee actions in the review process and providing prompt feedback to startup personnel if any inconsistencies are observed. No unacceptable conditions were identified with the QA/QC personnel involvement in the startup activitie .0 Independent Measurements, Calculations and Verifications During the course of this inspection, the inspector independently verified on a sampling basis, the prerequisites contained in the startup tests witnessed and monitored test specific parameters for adequate respons The inspector also independently verified several of the analysis steps in completed test procedures using the data collected during the test as part of the test results evaluation.

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6.0 Plant Tours

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The inspector made several tours of the facility during the course of the inspection including the reactor building, turbine building, control j structure and control room. No unacceptable conditions were note l

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7.0 Exit Interview An exit meeting was held on January 3,1986 to discuss the inspection findings as detailed in this report (see paragraph one for attendees).

At no time during the inspection did the inspector provide written inspection findings to the licensee. At the exit, the licensee did not identify any proprietary material that was contained within the scope of the inspection.

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