View source for IA-87-216, Submits Daily Highlight.On 870311,while Unit 1 Cooled Down from Hot Functional Test,Severe Water Hammer Event Occurred in RHR Sys Hx.Caused by Operator Apparently Missing Step in Procedure.News Release & Related Info Encl

{{Adams
| number = ML20215M470
| issue date = 03/13/1987
| title = Submits Daily Highlight.On 870311,while Unit 1 Cooled Down from Hot Functional Test,Severe Water Hammer Event Occurred in RHR Sys Hx.Caused by Operator Apparently Missing Step in Procedure.News Release & Related Info Encl
| author name = Kadambi N
| author affiliation = NRC OFFICE OF NUCLEAR REACTOR REGULATION (NRR)
| addressee name = Denton H, Lyons J, Vollmer R
| addressee affiliation = NRC
| docket = 05000498, 05000499
| license number = 
| contact person = 
| case reference number = FOIA-87-216
| document report number = NUDOCS 8705130257
| package number = ML20215M461
| document type = INTERNAL OR EXTERNAL MEMORANDUM, MEMORANDUMS-CORRESPONDENCE
| page count = 17
}}

=Text=
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                           'g                                                UNITED STATES
{.                g    _                         NUCLEAR REGULATORY COMMISSION
: 7.                E                                            WASHINGTON, D. C. 20555
              %.....$                                                      March 13, 1987 Decket Nos. 50-498 and 50-499 MEMORANDUM FOR:                       H. Denton*                R. W. Houston            F. Rosa R. Vollmer*               D. Crutchfield           V. Renarova J. Lyons*                 E. Rossi                 B. Clayton T. Novak*                 G. Lainas                R. Ballard F. Miraglia*              T. Spets                 G. Lear R. Bernero*               W. Russell               B. J. Youngblood G. Holahan*               C. McCracken             S. Varga L. Rubenstein*            R. Ballard               F. Schroeder C. Berlinger THRU:                                             tqr Nerses, Acting Director P R Project Directorate No. 5                .___
FROM:
Division of PWR Licensing-A N. P. Kadambi, Pro.iect Manager i W
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                                                                                                                     ~  hU
                                                                                                                                   )I lD PWR Project Directorate No. 5 Division of PWR Licensing-A

==SUBJECT:==
DAILY HIGHLIGHT i                                                                                                                        \
SOUTH TEXAS PROJECT, UNITS 1 AND 2 The Pro.iect Manager was informed by the Senior Resident Inspector for Operations that at 22:03 hours on March 11, 1987 when Unit I was being cooled down from the Hot Functional Test, a severe water hammer event occurred in the Residual Heat Removal System heat-exchanger. The primary system was at 350*F and 350 psig. The test being conducted was a demonstration of the 50*F/hr cooldown rate. _ The procedure for the test required component cooling water (CCW) flow to be established before primary coolant entered the RHR heat-exchanger. The operator apparently missed a step in the procedure.
l causing the hot fluid flow before the CCW flow. <The piping experienced two phase flow and subsequent water hamer events. - -Several hangers were bent or broken.- Leakage was observed in at least one flange connection. Part of the CCW piping shows deformation.
The applicant is conducting a detailed review of the event. The NRC resident staff is performing the appropriate follow-up. At this point, it is not clear as to how long it will take to recover from the event. A brief article in the Wall Street Journal about the event is enclose i(                                      ,
8705130257 870508
* PDR        FDIA BAUMAN87-216                       PDR                             N. P. Kadambi, Project Manager PWR Project Directorate No.-5 Division of PWR Licensing-A THESE COPIES MUST BE HANDCARRIED

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Houston Lighting's South Texas Plant Has Pipe Problem By TuowAs Perzincta Ja.
Staff Neporter of Tur WatJ.stmart Jou m mat.
HOUSTON-Houston Ughting & Power Co. said testing at its 85.5 billion South Texas Project nuclear plant touched off a significant " water hammer" effect in a                ' ~ ' ~       ~^
safety related cooling system.
The unexpected pipe rattling didn't im-
                  /
  ,                                                                           mediately appear to pose a significant b'
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                                    .       s
                                               '.             ?s s.
safety threat, as the newly built unit still    4
                                                        ,      e              basnt been loaded with nuclear fuel. Nev-          .
ertheless, three dosen workers were sent home early, and the problem caused con-cern among officials of Houston Ughting, a unit of Houston Industries Inc. The Nu-clear Regulatory Commission was noti-r.d.
The effect occurred Wednesday n!ght when the plant's Unit I was being cooled twn after a month of tests in advance of an initial fuel loading, which is scheduled for June. The tests, of several ms@r sys-tems at the plant, were being conducted
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with electrically generated rather than nu- k^'**',
                                                                                                                                                   . g , ;.    ,
clear beat.
As temperatures and pressures were re-duced to normal levels from test levels.
pipes began vibrating severely in one sys-tem, which draws relatively low-level heat
                          -                         "                       from components in the reactor contain-
:          ment building during coolglown periods.                              '
The cause of the water hammer wasn't clear to company engineers.
Houston Ughting said it didn't know yet if the unit was damaged or if the effect in-dicated there is a major design or con-  ~
struction defect.             .       .
In addition to Houston Ughtlag, the plant is owned by Central Power & Ught Co., a unit of Dallas-based Central & South l                                                                           West Corp., and the cities of San Antonio i                                                                           and Austin, Texas.
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Page 1 of 15        )
                                .                          Statien Preblea Rspart                                   OPOP03-ZA-0018 Rev. 1 g
Page 18 of 19  ,j   '
STATION PROBLEM REPORT
                                   .                           OPGP03-ZA-0018-1 (Page 1 of 2) l REPORT #                                                                                Q CLASS         SEVERITT LEVEL STATION PROBLEM l3l1l_l2l[l3
                                                                                                       ~                   ~
87-0005                                 REPORT                             l3lQl,,lNONQ DATI/ TIME DISCOVERED        3/11/87         /    2305               UNIT (l 1 l[l 2 l[l Common l[l NA DISCOVERED Digt!NG        Place'ihent'of RHR Trains B&C into service to semit comDletion Of. RHR Thermal Performance Preoperational Test 1-RH 3-04 CONDITION DESCRIPTION          Excerienced significant waterhamer induced vibrations A           in CCW Dioina to RHR Heat Exchancers
                   ~
                     ~ DISCOVERED BY         Huah Johnson                  DATE       3/11/87                PHONE EXT. 8614
                                                                                                                        ~
                     ' REVIEWED BY           N/A              DATE       N/A                        SS REVIEW REQ'D l_] NO (l YES    .
NOTIFICATION REQUIRED l3 NC l[lYES                    REQ'r.                                                 1 TECH. SPEC. APPLICABILITY l(lWOl[lTES#
IMMEDIATE ACTIONS TAKEN          tacored RHR Jrains B&C and initiated cooldown of B            reu en etnn waterhanwnar_                ,,
REMARKS Nn+4 n.d plant Management of Event SHIFT SUPERVISOR Wuah inhnenn                                                       DATE 3/16/87 i
REPORT REQUIRED           l[lNO l[lYES             REQ'MT.               10CFR50.55fe)
RESPONSIBLE DIVISION Qaartnr nnaratinnt                                    DUE DATE   3/16/87 l                C RECOMMENDEDACTION(s)l~l REMEDIAL l[l INVESTIGATIVE l~l CORRECTIVE             _
n.f4r4anru rannrtad tn_ _NDr nn 1/19/A7 hv Nuclear I iconsino.
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                                                                            .1-o & & 2 %
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(Page 2 of 2)
REPORT #
STATION PROBLEM l3l Preliminary REPORT l_l Final                                     PAGE 2 0F

==SUMMARY==
OF INVESTIGATION See Attachment 1                               .                                                                             .
i i         "--                    CAUSE See Attachment i                    >
D                   _ _
ACTIONS TAKEN/ PLANNED See Attachment M
CORRECTIVE OR COMPLETED BY                                                             APPROVED BY                                                  REMEDIAL ACTIONS
                                                                                            /)                                                                                         VERIFIED COMPLETE 4,
N D INVESTIGATOR. DATE RESPONSIBLE DIV M GR.
h   MW A-                             3-1137 DATE                                                            DATE E
VERIFIED BY                                                                                                                  DATE
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Page 3 Of 15
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STATION PROBLEM REPORT 87-0005 CCW SYSTEH WATER HAMMER Summary of Investigation Initial Conditions Hot Functional Testing was in progress on Unit 1 on 3/11/87 with the
_         following system conditions:
s                   .                                  -
                                                       ~
          .                 a.
                     *            --The Reactor Coolant System was being maintained at 350 F and 350 psig with all four Reactor Coolant Pumps in service,
: b.      The Component Cooling Water System was in service with all three pumps operating and flow being supplied to all three RHR Heat Exchangers.
c.
Trains A & C of Essential Cooling Water were in service supplying only Trains A & C ECW/CCW Heat Exchangers.
d.
Preparacions were underway to place Trains B & C RHR into service to support performance of Preop Test 1-RM-P-04, RHR Thermal Performance Test. Train A RHR was not available due to the RHR Pump breaker being out of service.
The purpose of this test was to vegify the capability of the RHR system to cooldown the RCS from 350 F to 250,F at a rate of 50 F per hour.
: 2. Sequence of Events       .
The following_ actions were performed in parallel on RHR Trains B & C.                         See Figure i for a schematic of the RHR and CCW piping.
a.
RHR Pump Suetion Isolation valves (RH-60 B/C and RH-61 B/C) were opened.
: b.      RHR Cold Leg Injection Valves (RH-31 B/C) were closed.
: c.      RHR Recirculation Valves (RH-67 B/C) were opened.
: d.      RHR Heat Exchanger Bypass Valves (RM-FCV-852/853) were verified closed.
: e.      Operator failed to close the RHR Heat Exchanger Outlet valves (RH-HCV-865/866) as required by procedure.
f.
RHR Pumps C & B were started at 2249 hours and 2253 hours respectively.
Note:    In this configuration the fluid in the RHR loop recirculated from the RHR Pump through the heat exchanger and back to the pump suction. No fluid was being drawn from the RCS.

s   'd  SS: PI 48/CE/PO                             Dd b Old DdH Sn N~ed Page 4 Of 15 The remaining actions were performed on RHR Trains B & C sequentially.
: g. The CCW flow to 3 & C RHR Heat Exchangers was terminated at 2254
,                                             hours, by closing the RHR Heat Exchanger CCW Outlet Valves (CC-FV-4548/4565), at the direction of the Startup Test Director to expedite heatup of the RHR loops. Thispinot aproceduralactig Note: Termination of CCW flow to the RHR Heat Exchangers resulted in g[p '                                    a low flow condition on the B & C train CCW Pumps as other g -?,       p                              normal CCW flow paths were also. isolated due to testing.
                          ~
t                       . h. CCW Pump B was secured at 2257 hours in response to a low flow alarm
                                            --con di t ion . -                            -
Note: This action was taken to permit increased pump flow on CCW Pump C and thereby clear the low flow condition on that Pump.
The action was gtabased u_pon a ioint decision between the i
g % ob and Qtartu1 Teat Direq1gIf it was(Rot a Wocedurab action. The B pump was secured because B Train ECW was not in N
service.
                      .      .         1. The RHR Cold Leg Injection Valves (RM-31 B/C) were opened at approximately 2302 hours.
Note: Due to the M tor'sI b                                                    to close the 3HR' Heat Exchanger Outlet Valves (RH-HCV-865/866) hot reactor coolant flow was established through the B & C RHR Heat Exchangers with no cooling water in service. This resulted in rapid heating of the CCW with resulting steam void formation as evidenced by increased CCW Sur6e Tank levels.
l                                      j. The $perator               - -- falle tA o p ,th M R..JI at Exchanger Bypass Valves                                                          .
;                                             (RM-FCV-852/853) as(required by proced                       _
i Note: This omission had little impact on the significance of the event.
l                                      k. The C Train RHR Heat Exchanger CCW Outlet Valve (CC-FV-4565) was opaned.
Note: This admitted cold water to the C Train RHR Heat Exchanger and resulted in minor water hammer as the steam voids were collapsed by the cold water. No CCW flow was provided to the B Train RHR Heat Exchanger as CCW Pump B was not operating and the RHR Heat Exchanger CCW Outlet Valve (CC-FV-4565) was therefore not opened by the operator.
: 1. CCW Pump B was restarted at 2310 hours in response to the high level condition in the CCW Surge Tank. However, the RHR Heat Exchanger CCW Outlet Valve (CC-FV-4548) was not opened by the operator.
Note: This action was taken to increase CCW system pressure. It                                                                     was believed that chilled water was leaking into the CCW System and increasing the CCW pressure would reduce the leakage.
I I
       .       -                 - -            , , , - . - . , . _ . - - . . - _ , -                . - , - - - . . - - . . .             - - - _     - - . . . . - - - . . . - . - . . ~

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                                 ,                                                                    Page 5 of 15 8.
: m.      RHR Pumps B & C were secured at 2315 and the associated' pump suction valves and cold leg injection valves were closed,
: n.      The C Train RHR Heat Exchanger CCW Outlet valve (CC-FV-4565) was closed in an attempt to stop the water hammer.
              .                    o.      The following actions were taken to slowly cool down the RHR Heat Exchangers:
: 1)   The B & C Train RHR Heat Exchanger CCW OCIV's (CC-HOV-130/190)
<         ,                   .                 were closed.      -
: 2)   The B Train RHR Heat Exchanger Outlet valve (CC-FV-4548) and the B & C Trains RHR Heat Exchanger CCW OCIV's (CC-HOV-130/190) were manually cracked open at approximately 2330 hours. Cooling was maintained until the CCW return temperature from the RHR
                 ~
Heat Exchangers was less than 200 F and all water hammer had stopped.
: p.      Plant management was notified of the incident at 0420 hours on
                   .     ..                3/12/87.
            - ,-            3. Analysis of Events This incident occurred while an operator was placing two trains of RHR in service to support the performance of Freop Test 1-RH-P-04. The controlling HTT procedure directed that this operation be performed in accordance with Operations Work Order Request (OWOR) 1-RO-RM-236.         This 0 WOR is a modified version of the normal operating procedure
;                                  iPOE02-RH-0001, Residual Heat Ramoval System Operation, for use during HFT only. While performing this procedure the Operator f ailed to close the iir RHR Heat Exchanger Outlet Valves (RH-HCV-865/866) as directed by the
                                  .proqedgre. This resulted in initiation of flow of het RCS fluid (350 )
through the RHR Heat Exchangers when the Cold Leg Injection valves were subsequently opened.       Since CCW to the heat exchangers had been terminated at the .rerb_al direction of the Startup Test Director to enhance heatup of the RHR loops, no cooling medium was provided and rapid heatup and void formation of the CCW in the heat exchangers occurred.
When the RHR Heat Exchanger CCW Outlet Isolation valves were reopened, CCW flow was established to the C Train RHR Heat Exchanger only. This occurred because CCW Pump B had been secured to clear flow alarms on CCW Trains B & C.       This resulted in Train D RHR Heat Exchanger being without cooling water for a longer period of time.        This prolonged no flow condition permitted a greater degree of heating and void formation in the B RHR Heat Exchanger which contributed to a greater degree of water hammer on that Train.
i                                                                .

4 'd    45:r! L8/C2 r0       3 dis aid 3dN 50 WOdd Page 6 of 15 Cause Failure to follow procedure in that the Operators
: a. skipped two steps, and
: b. under verbal direction of the Startup Test Director, performed steps 5 not in the procedure.
             ~
Action Taken/ Planned
                 ~
t                    .                              ~    -
: 1. Plant management formally convened a meeting of Operations, Startup and
                                $ngineering personnel involved with the incident at 6:30 AM on         March 12, 1987.
The purpose of the meeting was to
: a. Review and summarize the events which occurred during the incident.
: b. Initiate evaluation processes to establish plant physical status and
               .    ~                  recommend recovery plans, and
: c. Initiate a conduct of operations review for procedural adequacy before commencing additional testing activities.
: 2. Actions taken/ planned to evaluate and correct conduct of operations deficiencies are provided in Attachment 1.
: 3. Actions taken/ planned to evaluate and correct physical plant deficiencies are provided in Attachment 2.

8   'd    LS PI 48/C2/PO       3 d15 A!d OdN Sn WOdd
                            .                                                                  Page 7 of 15 ATTACHMENT _1 To evaluate f actors which may have contributed to the operator error experienced during this incident, plant management designated a task force to review the conduct of operations involved. The task force evaluated procedural form and context, procedural compliance as well as the startup and operations interface. The findings of the task force and actions taken for
          ..            recurrence control are highlighted below.
The members of the task force were t                  . T. E. Underwood - C04A Manager (Chairman)'
X. P. Mulligan - Shift Technical Advisor (SRO Licensed)
J. T. Lacasse - System Engineer
             .              W. L. Giles - Shift Supervisor C. P. Bogolin - Training Instructor (Consultant - Previously SRO Licensed)
                .     ~     L. Dusak - System Engineer
      - - - -               G. Ondriska - Startup Supervisor J. W. Loesch - Plant Superintendent (SRO Licensed) - Part Time
: 1. . Contributina Factors
: a. Procedural Control / Compliance
: 1)   Due to rapidly changing and abnormal system lineups and equipment availability, the Operations Work Order Request was developed se a tool to easily communicate startup instructions to Operations while systems are under Startup control.       Startup instructions are reviewnd by the s_hift supervisor n        it found,
_act.ap.t ahl.a , are implemented by NPOD operators. On   master copies of OWOR's are available in the Control Room. As such, a working copy was not available, or required. which would have
,                                      allowed the operator to annotate check off lists provided to aid l                                      in the verification that procedural steps are completed.
: 2)   OWOR's make liberal use of copies or marked up copies of
;                                      permanent plant procedures. This is desirable from the view of I                                      utilizing and verifyJng,ad,equacy of plant procedures. Overuse of such {a~r Q o g leag revisions, as is judged to be the case in this incident, contribute to the likelihood of misoperation of plant equipment. Although determined to be
;                                      technically adequate, the number of changes, the intent of changes, and the use of a partial line out of one step of the l-                                     OWOR procedure were causal factors in this incident.
: 3)   The normal plant operating procedure 1 POP 02-RH-0001, Residual Heat Removal System Operation, was also reviewed and found to be technically adequate.
i L

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                           .        ,'                                                                     Page 8 of 15 v
                                                             /
      ,-                             b.        Startup/ Operations _ Interface
: 1)   Although there was a general discussion of upcomina shift activitiss during sh'if t turnover, there is no evidence of a detailed pre-test briefing of personnel involved prior to the RHR Thermal Ferformance Test. Such a briefing should have occurred, especially in view of the fact that the reactor operator involved had not previously used the OWOR directing the test. The Startup Test Director, Shift Supervisor and Unit
_ . M^*A , 4,g. Supervisor all considerad the operation to be routine because t
d ' ,, ,.y g y,   the procedure bed been successfully performed before, and they
                                                   -considered the Operator to be both knowledgeable and competent.
: 2)    Evolutions conducted by Startup, if(judghbtebesimpleand straight forward, do not require written irmtructions and may be verbally directed by the Startup engineer. More complex
                ~
evolutions are guided by OWOR. During the performance of the test in question, the Startup Engineer verbally directed the operator to take steps not required in the written OWOR. This is contrary to an operators training where verbatim compliance with written procedures is required, it may cause confusion as       ,
to current and required system configuration, and it fosters the
             .-                                      perception that the Startup representative is solely responsible and accountable for the proper performance of procedures. In addition, this direct instruction by the Startup engineer to the 4
control room operator to deviate from an existing OWOR, without informing Shift Supervision, dilutes the Supervisors knowledge of specific ongoing activities and changes in approved procedures and limits their ability to judge the degree of direct supervision required for a particular evolution. This is judged as a breakdown in communication which is a contributory        ,
cause to this incident.
: 2.        Actions Taken/ Planned
: a.        Revise procedure iTGP)3-ZA-0004, operations Work order Request, to provide additional control over the 0 WOR development and implementation process as follows:
: 1)   Provide specific direction requiring operators to obtain working copies of written procedures associated with OWOR's and to annotate procedural step check offs when provided.
4'(               2)   Provide specific direction requiring verbatim compliance with Jgu              ,c>              written procedures associated with OWOR's and prohibiting ne                        deviation from such procedures based upon verbal direction.
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Page 9 of 15 i
: 3)    Provide specific direction requiring the reissuance of the CWOR utilizing the approved review process when circumstances preclude verbatim compliance with written procedures associated with the OWOR.
ACTION DUE DATE:                              3/12/87 - ACTION COMPLETE RESPONSIBLE INDIVIDUAL: W.H. KINSEY
: b. Issue a directive to Shift Supervisors and Chemical Operations Foreman requiring that, as the OWOR approval authority, they review
                 -                 OWOR's from both a human engineering as well as a technical t
standpoint to ensure that extensive use of markups to, or confusing
                    ,            - markups of,- existing operating procedures will not be allowed, but will require reformatting to eliminate areas of potential misunderstanding.
ACTION DUE DATE: 3/17/87 RESPONSIBLE INDIVIDUAL: J.W. LOESCH
: c. Brief all operating crews on this incident, including sequence of events, root cause, contributing factors, and corrective actions
                . -                taken.
       "   --                      ACTION DUE DATE: 3/20/87 RESPONSIBLE INDIVIDUAL: J.W.                               L0ESCH / W. H. Kinsey
: d. Perform a management review of the continued practice of using the OWOR process for system operations.
ACTION DUE DATE: 3/30/87 RESPONSIBLE INDIVIDUAL: J.W. LOESCH
: e. Request Engineering to evaluate the possibility of installing an interlock or alarm when CCW flow is present to the RHR Heat Exchanger and RHR is attempted to be operated.
ACTION DUE DATE: 4/1/87 RESPONSIBLE INDIVIDUAL: J.W. L0ESCH
                                                                                                                                                                                                          ]

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        . .                       ,                                                                 Page 11 of 15 ATTACHMENT 2 CCW SYSTEM WATER HAMMER ENGINEERING EVALUATION 1.0 _ DESCRIPTION OF EVENT
                      .During the RHR preoperational test for cooldown to 250' F a hydraulic transient event occured on 03/11/87 at approximately 11:00 p.m.. Based on NPOD's review of the event scenario it was determined that the system was not in a normal operating alignment at the time of the water hamer.
       .,              ~2. 0 ENGINEERING ACTIONS TAKEN .
Efigineering was notified of the event 1:45 a.m. on 03/12/87. The immediate actions taken by engineering were to assess the damage and identify the i                       potential cause of the water hamer in order to define the steps that were necessary to ensure the plant was in a safe condition and then to resume
                   ,    testing. Attachment (1) provides a sumary of actions taken and responsibility.
                 ~
3.0 ENGINEERING EVALUATION TO C0_NTINUE TESTING j
* The following is a sumary of the action steps taken on 03/12/87 to release l             _..       startup to continue testing:
j                              a) Walkdown of RHR and CC System
^                                     Based on the event scenario the "B" and "C" trains of RHR and CCW were in service at the time of the event. A Walkdown was performed of the piping systems on both trains including an inspection of the pipe, pipe supports, instrunientation, valves, RNR pump and RHR heat exchanger. It was determined that the area of damage occured on the
 .                                    "B" train of CCW to/from the RHR heat exchanger and RHR pump seal I                                    water cooler. In sumary the damage included bent and broken pipe i
supports, broken valve handwheel and a dent in a pipe spool. This damage was documented on NCR's SP-4725, 55-4692, SP-4726.
1                                     Westinghouse performed a walkdown of the RHR heat exchanger nozzles and found no evidence of damage by' visual inspection I                               b)    Photographs of Damage Photographs of the damaged areas were taken i
l l.
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         .         .                                               CI*d                                                                        IO:5I L8/C2/r0       3 d1S old DEN Sn WOdd
       .                                                                                                                                                                   Page 12 of 15 3.0 ENGINEERING EVALUATION TO CONTINUE TESTING (Continued) c) Recovery Plan Isometrics wore marked up to identify the location of damaged supports and piping displacements were determined based on waixdowns. Based on these displacements stress analysis was performed to estimate the maximum stresses in the pipe and equipment / containment penetration nozzles. Based on this stress analysis it was determined that the piping system responded in the
           -                       elastic region of'the ' stress / strain characteristics of the piping.
Tiits wa~ s also ' confirmed' by the walkdowns which revealed no plastic
'                                  deformation of the piping other than a localized dent in one pipe spool where it had impacted a pipe support. It was further determined that the damaged supports did not impact the dead weight, thermal or normal dynamic load carrying capacity of the piping i
system. Based on this NCR $5-4592 was given a conditional release to
            .       _,             allow startup to continue testina.                                                                               In addition NCR SP-4725 was           _
conditionally released based on an acceptable NDE on the dented pipe spool.                                                                                                                                                 [
       ~   '-
Based on a report that the upper flange bolts on valve CC-0124 were                                                                                      '
possibly overtorqued to stop leakage at the time of the event, NCR SP-4726, revision "01" was written and dispositioned to replace any damaged bolts / nuts and have them all retorqued.
d) Perform RHR Heat Exchanger leak Test It was determined by Westinghouse that the pressure integrity of the tube side (RHR) of the heat exchanger should be verified. A test was conducted which pressurized the RHR System with the Low Head Safety Injection pumps and leakage was monitored by change in level in the CCW surge tank. The test was conducted and no leakage was evident.
e) The following data was collected to analyze the cause of the damage.
: 1. RHR heat exchanger trains B and C outlet temperature
: 2. CC outlet temperature from RHR heat exchangers and RHR pump coolers for both trains 8 and C.
: 3. CC train B heat exchanger outlet temperature, flow and pressure.
: 4. QOPS status alarms.
ne cause of the damage was determined to be from hot water (308 to 313' F) flashing partially to steam and the steam bubbles collapsing. The water was heated in the CC side of the RHR heat exchangers by the heat from the hot (350' F) reactor coolant.
                                    "B" train CC was isolated by closing valve FV 4548 and "B" CC pump secured. Thermal expansion caused PSV 4549 to lift. The hot water relieving from PSV 4549 flashed partially to steam in the depressurized system. The steam bubbles alternately forming and collapsing caused the water hammers and subsequent damage.
2-7195R/0168R

et*d     20:51.e.seca/co       o dis nIa aan sn woes
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page 13 of 15
  'i 3.0 ENGINEERING EVALUATION TO CONTINUE TESTING (Continued)
                                 "C" train CC was isolated with FV 4565 however "C" train CC pump was operating supplying flow to various components including RHR pump seal cooler. "C" train hamered due to the same scenario as "B" train however flow was maintained in the line to which PSV 4566.
discharges helping mix the hot and cold streams and reducing the magnitude of the hamer.
                   ~
f) Based on.the completion of all the required action steps above,
     .,                   ,     startup was author,ized,to continue testing the RHR system for HFT.
               ~
g) Westinghouse r'eviewed the criteria for operation of the RHR and CCW system in relation to initiating RHR at 350' F and 350 psig. It was
                               ' determined that the existing Station Operating Procedure                             ,
1 POP 02-RH-00001 is consistent with the Westinghouse operating
                 ,               instructions in the System Descriptions.
               . 4,0 ACTION ITEMS POST HFT Attachment (2) provides a sumary of the action items to complete Engineerings evaluation and recommendations for restoring the system to fully operational
_,      status.
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7195R/0168R

COf ST5 TEN MATER leNEER                     J                                  .
A.       Items Needed To Belease For Cagletion of WT                                                                                  Page 14 of 15                   .
ACT!!be ITDt5            .                                                               Ac11gn h TT.          ''
ST TUS
: 1.      Caglete Walkdown of ledt and CC System                                                         ,     !      .
: a. IBR Neat Eachanger (1) Exaelne nozzles for damage / stress                                    if/SEO(M&QS)              After WT (2) Evaluate internals, considering the heat enchanger acted              W (Coulter)               LPSI test ullt address for tf T as a boiler                                                                                                                                  ,
: b. IIHR Puesp                                                        .                                     l l                     (1) Look at nozzles and pu , alignment                                     Startup (Daly)            Complete                                      ,
: c. Loop Piping                                                                   SEC (Tolley/ Carlo)       Casplete Ceeplete walkdowns on CC piplag from heat enchanger felet (SM001) eut to contafaseet penetration. Also complete asalkdemns on CC piping from heat exchanger outlet out to FV-4548. Leedt for hent/
broken hangers, shtiting in line, doeting/deforantion, leakage (flange on CCcI24 was reported leaktgl. mar ===nt abservatless.
!                d. Perform neelkdome of the remainder of the 8 loop. CC System Piptog         SE0 (Tolley/ Carlo)       Cgpiete
: e. Perform Stress Calc (s)                                                    SEO (Carlo)               Complete
 ,               f. Walkdosse instruments and instrtment Ilmes in the B loop, CC System         SES (Trefethern)          Complete. Caly item is leding PSV 4549
!        2.      Take Photographs of Danese                                                      Startup (Ulrich)           Complete sn
 !      3.       Prepare Recovery Plan                                                                                         *                                               ~
i
: a. Evaluate the observatless from item 1 above; determice if the              SED (All)                  Coglete. No teep alt's required Q.
system can be repaired sufficiently for centinued testleg.
: b. Provide marked up 150(s) and/or hanger sheets identifyles actions            SED (Tolley/ Carlo) to be taken (e.g. replace supports, attach temporary hangers / chain                                  Not ret,utred. No temp alt's required              cy I                     falls etc.). ~ Identify (list) itans to be repaired after ET.                                                                                           o
;                c. HDT one beat weld / pipe                                                     SE0/Ebasco (foung) j Complete. Could only do partial MT; hanger covers part of dent. No indications noted                                              P-q                d. Deterstne af hydro is required                                             SEO (All)                 Hydro not required.                                CD
: 4.       Write                        Problem Report Perm OMPo3-EA *ce?                  WOG                       F/C 3/13/87                                        O
: 5.                                                                                                                                                                     s Write not(s) on CC124 bolts P51-4545 ledage and drale valve leakage.             SE0 (Connelly)            Ceeplete All to be conditionally released for WI except CCl24 bolts. Condition-                                                                                        o'*
ally release NCRs $P04726. 5504762, SPO4725 for NT.
: 6.      Adequacy Letter, Accompanted by Recovery Plan Action Itess                       SES (Isoreton)            Not required. (Use Conditional Release)            g i       7.      Walkdown letdown itx Ilse (CV side)                                              SE0 {Tolley)              Conylete                                           ct
!                                                                                                                                                                             t-
: 8.      Perform BHR Ma leak test ettlizing LPSI pumps                                    Startup (Daly)
* Complete. No leakage
: g.      tittale FA 4518. TA 4515 and FA 4547 computer readings from 2200 hours i               3/11/87 through 0200 hours 3/12/87 HL&P (Brown)              Complete                                           b cr
;       10. Examine calibration en IV 4547                                                       Startup (Daly)            F/C 3/12/87                                        N
: 11. Identify root cause                                                                  SEC (All)                 Valve alignment resulted in localized boiling in the best Wu.                            $
{       12. Release Startup to continue testing 8 Trafn of CC                                   SEC                        Complete                                           E o
4851Y/0145Y
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* B. Itses needed Post G T                                                 mp,,u 42)              ,             ,      .
AC13e ITEst5                                                               ACTIN       TY ,               STARIS                                     *;       '
l
: l. Ceeplete Evaluation of me Heat Exchanger:                                               *
: a. Provide stress calcs/ valves on nozzle loads to 1destleghouse      20 (Carlo)                  J/.t/87
: b. Evaluate nerzle leads                                              Westleghouse (Glasbergen)   Ju.t# #                             -
: c. Evaleate internals                                                 idestinghouse (Glashergen)  3 f..gg7 .                                  .
: 2. Restore Piple5/Haagers                                                                                      l                       ,
: a. Provide disposittaa en Muts, as felleus:
(1) uut SP-Oe726 - Flange bolts brekee handshoel                   1 0 (Piplag)                   Ceegliete                                     .g (2) sta 55-04792 - Supports                                       10 (Telley)                    3 14 :187                                       ..
(3) MCR SP-04725 - Pipe test                                       M O (Telley)                   3fael87                                            .I
: b. Perform final stress recencillation and further IST (as regatred)  2 0 (Carla/Tolley)            yfa.gry                                          a to resolve open geestfan se pipe dents
                                                                                                                  .                                          C
: 3. Ideetify Other Iteas to be Addressed. Resolve Accordingly                                                                                              e o
: a. aatterfly valves, seats                                              2 0 (Pipfeg)                 3f,, fry  I                                       F'
: b. Contalammet penetretten mezzle loads                               20 (Carlo)                       ,
      <. h%,hyu otur of m                                                     SJ                           .ryg
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D 4851V/0145V                                                                                                                                              E o
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