Information Notice 1993-67, Bursting of High Pressure Coolant Injection Steam Line Rupture Discs Injures Plant Personnel: Difference between revisions

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| issue date = 08/16/1993
| issue date = 08/16/1993
| title = Bursting of High Pressure Coolant Injection Steam Line Rupture Discs Injures Plant Personnel
| title = Bursting of High Pressure Coolant Injection Steam Line Rupture Discs Injures Plant Personnel
| author name = Grimes B K
| author name = Grimes B
| author affiliation = NRC/NRR
| author affiliation = NRC/NRR
| addressee name =  
| addressee name =  
Line 13: Line 13:
| document type = NRC Information Notice
| document type = NRC Information Notice
| page count = 14
| page count = 14
| revision = 0
}}
}}
{{#Wiki_filter:U -AUUNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555August 16, 1993NRC INFORMATION NOTICE 93-67: BURSTING OF HIGH PRESSURE COOLANT INJECTIONSTEAM LINE RUPTURE DISCS INJURES PLANTPERSONNEL
{{#Wiki_filter:U                             -AU
 
UNITED STATES
 
NUCLEAR REGULATORY COMMISSION
 
OFFICE OF NUCLEAR REACTOR REGULATION
 
WASHINGTON, D.C. 20555 August 16, 1993 NRC INFORMATION NOTICE 93-67:     BURSTING OF HIGH PRESSURE COOLANT INJECTION
 
STEAM LINE RUPTURE DISCS INJURES PLANT
 
PERSONNEL


==Addressees==
==Addressees==
All holders of operating licenses or construction permits for nuclear powerreactors.
nuclear power
 
All holders of operating licenses or construction permits for
 
reactors.


==Purpose==
==Purpose==
The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to remind addressees of the hazards associated with steam drivencoolant injection systems such as the high pressure coolant injection (HPCI)system and the reactor core isolation cooling (RCIC) system at BWRs and theauxiliary feedwater system at PWRs. It is expected that recipients willreview the information for applicability to their facilities and consideractions, as appropriate, to avoid similar problems. However, suggestions Xcontained in this information notice are not NRC requirements; therefore, nospecific action or written response is required.BackgroundThe purpose of HPCI steam exhaust rupture discs is to protect the HPCI turbinecasing and associated exhaust piping from an overpressure event if the normalexhaust path to the suppression pool becomes blocked. At Quad Cities Station,two 40.6-cm [16-inch] stainless steel discs are installed in series with a6.4-cm [2.5-inch] spacer between them to allow for a pressure sensorinstrumentation line. The pressure sensor, while serving no control function,actuates an alarm in the control room at 68.9 kPa [10 psig] to alert theoperators that the inner disc is leaking. The normal range of the HPCIexhaust steam pressure is 172 to 207 kPa [25 to 30 psig].- The HPCI highexhaust pressure turbine trip setpoint is 689 kPa [100 psig] and is sensed bypressure sensors located downstream from where the section of pipingcontaining the rupture discs branches off from the exhaust piping. Thesection of piping containing the rupture discs is mounted vertically over theturbine exhaust and vents directly to the HPCI room. Pressure greater than1034 kPa [150 psig] in the exhaust line will cause the inner disc to ruptureand impact the outer disc, releasing steam into the HPCI room.
information
 
The U.S. Nuclear Regulatory Commission (NRC) is issuing thissteam driven
 
notice to remind addressees   of the hazards associated     with
 
injection (HPCI)
coolant injection systems such as the high pressure coolant at BWRs and the
 
system and the reactor core isolation cooling (RCIC) system                       will
 
auxiliary feedwater system at PWRs. It is expected that recipients       and  consider
 
review the information for applicability to their facilities                                   X
 
actions, as appropriate, to avoid similar problems. However, suggestions     therefore, no
 
contained in this information notice are not NRC requirements;
specific action or written response is required.
 
Background
 
the HPCI turbine
 
The purpose of HPCI steam exhaust rupture discs is to protect         event    if the normal
 
casing and associated exhaust piping from an overpressure Quad Cities Station, exhaust path to the suppression pool becomes blocked.             At
 
in series with a
 
two 40.6-cm [16-inch] stainless steel discs are installed                   sensor
 
6.4-cm [2.5-inch] spacer between them to allow       for a   pressure
 
while  serving    no  control    function, instrumentation line. The pressure sensor,                             to  alert  the
 
actuates an alarm in the control room at 68.9     kPa   [10   psig]
                                                                          of the HPCI
 
operators that the inner disc is leaking. The normal range The HPCI high
 
exhaust steam pressure is 172 to 207 kPa [25     to 30 psig].-
                                                                            and is sensed by
 
exhaust pressure turbine trip setpoint is 689 kPa [100 psig] piping
 
the  section      of
 
pressure sensors located downstream from where                         piping. The
 
containing the rupture discs branches off from the exhaust vertically over the
 
section of piping containing the rupture discs       is mounted
 
greater than
 
turbine exhaust and vents directly to the HPCI room. Pressure     inner  disc  to rupture
 
1034 kPa [150 psig] in the exhaust line     will cause   the
 
steam  into  the  HPCI    room.
 
and impact the outer disc, releasing


==Description of Circumstances==
==Description of Circumstances==
During a quarterly inservice test of the HPCI pump at the Commonwealth EdisonQuad Cities Station, Unit 1, on June 9, 1993, the exhaust steam line rupture9308100248F QrRi IN 93-67August 16, 1993 discs burst, releasing steam into the HPCI room, burning, and slightlycontaminating, five workers. The rupture discs burst within one second afterthe turbine was started. Fire doors between the Unit 1 and Unit 2 HPCI roomswere blown off their hinges into the Unit 2 HPCI room. Both sets of doubledoors that are part of the secondary containment boundary were also blownopen. The floor latch on the inner containment door was bent; the outer doorswere also slightly damaged, but were repaired, closed and sealed approximately35 minutes after the event. The steam release was terminated by automaticisolation of the steam supply line on high HPCI turbine area temperature about20 seconds into the event.DiscussionUpon investigating the event, the licensee determined that water hadaccumulated in the turbine casing because the drain system level switches forthe Unit 1 HPCI system had failed. In April 1992, the licensee performed areliability-centered maintenance study which recommended the level switches beincluded in the preventive maintenance program but the recommendation had notbeen acted on at the time of the event. The Unit 2 HPCI drain system levelswitches were also found to be inoperable.The slug of water created during the HPCI turbine roll passed from the turbinecasing to the vertical exhaust line and compressed the air in the 40.6 cm[16 inch] line containing the rupture discs. The resulting pressure pulsecaused the inner rupture disc to burst, which impacted the outer disc asdesigned and caused it to burst as well. The exhaust line pressure sensors,located in the horizontal 61 cm [24 inch] exhaust line that tees off from thevertical 40.6 cm [16 inch] rupture disc line, did not detect a high pressure(see Figure 1). The pressure switches were within tolerance and should haveimmediately isolated the steam supply upon sensing a high exhaust pressurebefore the rupture discs burst. The fact that a high exhaust line pressurewas not detected indicates two possible causes for the disc rupture. Eitherthe inner rupture disc was degraded and burst at lower-than-design pressure,or the pressure pulse actually exceeded the design pressure and caused thedisc to burst, relieving the exhaust line pressure before the downstreampressure sensors detected a high pressure condition.While inspection of the rupture discs did not reveal any degradation fromcorrosion or aging, the vendor, Black Sivalls & Bryson, Inc, stated that thediscs are warranted for one year of service under normal conditions. The HPCIand RCIC rupture discs at Quad Cities Station had been in service for 20 yearsand were not part of any scheduled inspection or preventive maintenanceprogram. When consulted about the event, the vendor advised against using thespare discs in the plant storeroom because they were purchased at the sametime as the failed discs. The licensee later replaced the failed discs withnew units. Before this event, the licensee recently replaced a HPCI rupturedisc during a refueling outage at the Dresden Station, a plant similar to QuadCities, after finding a crack in the disc during an inspection. The rupturediscs were inspected at the Dresden station as part of an enhancement to thepreventive maintenance program that was recommended by a reliability-centeredanalysi I IIN 93-67August 16, 1993 The steam injured five workers, four of whom were participating in the HPCIpump surveillance test. The fifth, and m6st severely. injured worker was ahealth physics technician in the room on routine rounds, who was not aware ofthe danger posed by the surveillance test. The test procedure contained nospecific guidance on room occupancy. Interviews with the workers revealedthat they had performed the surveillance in the past and were familiar withthe process. This familiarity may have led to a relaxed attitude towardpersonal safety. The workers stated that during previous surveillances theysometimes evacuated the room before rolling the turbine, or stood near thedoors to be ready to escape. The licensee made no routine announcement overthe plant paging system to alert plant personnel before the HPCI-turbinestart, and the workers were not prepared for the turbine to start.A lack of constant communication between the workersand the control room mayhave contributed to the personnel injuries. If a control room operator hadbeen in contact with the workers in the HPCI room during the turbine roll, theworkers would have been aware of the impending turbine start and, after start,the steam supply might have been manually-isolated or the turbine manuallytripped before the automatic isolation caused by the high area temperatureointhe HPCI room.When the Unit 1 HPCI rupture disc failure caused the fire doors to be blownoff their hinges and into the Unit 2 HPCI room, one of the doors impacted apipe hanger in the room and moved it 5.1 centimeters [2 inches]. If the steamrelease had resulted from a high energy line break from the inlet side of theHPCI steam line instead of the exhaust line, the damage to the Unit 2 HPCIsystem could have been more severe. While high energy line breaks have beenanalyzed for safety systems at all plants, the doors to rooms containing highenergy steam lines may not have been included in the analysis. For example,at Duane Arnold Energy Center, the licensee discovered that while the HPCI andRCIC rooms were qualified for pressures of 26.2 kPa [3.8 psig], the doorsbetween these rooms and the reactor building would yield at 6.9 kPa [1 psig].The licensee for the Quad Cities Station will implement a preventivemaintenance schedule for both the HPCI and RCIC rupture discs and the levelswitches. The licensee will review the surveillance test procedure andevaluate the missile hazard created by the fire doors. The licensee replacedthe rupture discs for the Unit 2 HPCI and RCIC systems with new ones after theevent at Unit 1 and is considering burst testing the removed discs todetermine if they are degrade IN 93-67August 16, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grim s, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts: Clark Vanderniet, RIII(708) 790-5594David Skeen, NRR(301) 504-1174
Edison
 
During a quarterly inservice test of the HPCI pump at the Commonwealth       line  rupture
 
9, 1993,  the  exhaust      steam
 
Quad Cities Station, Unit 1, on June
 
9308100248 F                                                                    QrRi
 
IN 93-67 August 16, 1993 discs burst, releasing steam into the HPCI room, burning, and slightly
 
contaminating, five workers. The rupture discs burst within one second after
 
the turbine was started. Fire doors between the Unit 1 and Unit 2 HPCI rooms
 
were blown off their hinges into the Unit 2 HPCI room. Both sets of double
 
doors that are part of the secondary containment boundary were also blown
 
open. The floor latch on the inner containment door was bent; the outer doors
 
were also slightly damaged, but were repaired, closed and sealed approximately
 
35 minutes after the event. The steam release was terminated by automatic
 
isolation of the steam supply line on high HPCI turbine area temperature about
 
20 seconds into the event.
 
Discussion
 
Upon investigating the event, the licensee determined that water had
 
accumulated in the turbine casing because the drain system level switches for
 
the Unit 1 HPCI system had failed. In April 1992, the licensee performed a
 
reliability-centered maintenance study which recommended the level switches be
 
included in the preventive maintenance program but the recommendation had not
 
been acted on at the time of the event. The Unit 2 HPCI drain system level
 
switches were also found to be inoperable.
 
The slug of water created during the HPCI turbine roll passed from the turbine
 
casing to the vertical exhaust line and compressed the air in the 40.6 cm
 
[16 inch] line containing the rupture discs. The resulting pressure pulse
 
caused the inner rupture disc to burst, which impacted the outer disc as
 
designed and caused it to burst as well. The exhaust line pressure sensors, located in the horizontal 61 cm [24 inch] exhaust line that tees off from the
 
vertical 40.6 cm [16 inch] rupture disc line, did not detect a high pressure
 
(see Figure 1). The pressure switches were within tolerance and should have
 
immediately isolated the steam supply upon sensing a high exhaust pressure
 
before the rupture discs burst. The fact that a high exhaust line pressure
 
was not detected indicates two possible causes for the disc rupture. Either
 
the inner rupture disc was degraded and burst at lower-than-design pressure, or the pressure pulse actually exceeded the design pressure and caused the
 
disc to burst, relieving the exhaust line pressure before the downstream
 
pressure sensors detected a high pressure condition.
 
While inspection of the rupture discs did not reveal any degradation from
 
corrosion or aging, the vendor, Black Sivalls & Bryson, Inc, stated that the
 
discs are warranted for one year of service under normal conditions. The HPCI
 
and RCIC rupture discs at Quad Cities Station had been in service for 20 years
 
and were not part of any scheduled inspection or preventive maintenance
 
program. When consulted about the event, the vendor advised against using the
 
spare discs in the plant storeroom because they were purchased at the same
 
time as the failed discs. The licensee later replaced the failed discs with
 
new units. Before this event, the licensee recently replaced a HPCI rupture
 
disc during a refueling outage at the Dresden Station, a plant similar to Quad
 
Cities, after finding a crack in the disc during an inspection. The rupture
 
discs were inspected at the Dresden station as part of an enhancement to the
 
preventive maintenance program that was recommended by a reliability-centered
 
analysis.
 
I   I
 
IN 93-67 August 16, 1993 The steam injured five workers, four of whom were participating in the HPCI
 
pump surveillance test. The fifth, and m6st severely. injured worker was a
 
health physics technician in the room on routine rounds, who was not aware of
 
the danger posed by the surveillance test. The test procedure contained no
 
specific guidance on room occupancy. Interviews with the workers revealed
 
that they had performed the surveillance in the past and were familiar with
 
the process. This familiarity may have led to a relaxed attitude toward
 
personal safety. The workers stated that during previous surveillances they
 
sometimes evacuated the room before rolling the turbine, or stood near the
 
doors to be ready to escape. The licensee made no routine announcement over
 
the plant paging system to alert plant personnel before the HPCI-turbine
 
start, and the workers were not prepared for the turbine to start.
 
A lack of constant communication between the workersand the control room may
 
have contributed to the personnel injuries. If a control room operator had
 
been in contact with the workers in the HPCI room during the turbine roll, the
 
workers would have been aware of the impending turbine start and, after start, the steam supply might have been manually-isolated or the turbine manually
 
tripped before the automatic isolation caused by the high area temperatureoin
 
the HPCI room.
 
When the Unit 1 HPCI rupture disc failure caused the fire doors to be blown
 
off their hinges and into the Unit 2 HPCI room, one of the doors impacted a
 
pipe hanger in the room and moved it 5.1 centimeters [2 inches]. If the steam
 
release had resulted from a high energy line break from the inlet side of the
 
HPCI steam line instead of the exhaust line, the damage to the Unit 2 HPCI
 
system could have been more severe. While high energy line breaks have been
 
analyzed for safety systems at all plants, the doors to rooms containing high
 
energy steam lines may not have been included in the analysis. For example, at Duane Arnold Energy Center, the licensee discovered that while the HPCI and
 
RCIC rooms were qualified for pressures of 26.2 kPa [3.8 psig], the doors
 
between these rooms and the reactor building would yield at 6.9 kPa [1 psig].
 
The licensee for the Quad Cities Station will implement a preventive
 
maintenance schedule for both the HPCI and RCIC rupture discs and the level
 
switches. The licensee will review the surveillance test procedure and
 
evaluate the missile hazard created by the fire doors. The licensee replaced
 
the rupture discs for the Unit 2 HPCI and RCIC systems with new ones after the
 
event at Unit 1 and is considering burst testing the removed discs to
 
determine if they are degraded.
 
IN 93-67 August 16, 1993 This information notice requires no specific action
 
you have any questions about the information in this or written response. If
 
the technical contact listed below or the appropriate notice, please contact
 
Reactor Regulation (NRR) project manager.             Office of Nuclear
 
Brian K. Grim s, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:   Clark Vanderniet, RIII
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachments:
1. Figure 1, "Simplified Layout of Quad Cities
 
Station HPCI Turbine Exhaust Steam Line"
2. List of Recently Issued NRC Information Notices
 
Cq~
        0cr                                                                                                                  1 cO
 
Cd)h  r-
          4
              0                                                                      OUTER RUPTURE DISC  _____
    \TO                                                                                                                                    VENT TO
 
HPCI ROOM
 
INNER RUPTURE DISC
 
[1 In]
                                                                              2                                  40.6 cm
 
[16 in]
                            CLOSABLE            CHECK
 
CHECK VALVE          VALVE        I
 
SUPPRESSION
 
50.8 cm
 
LOCKED                        I                                                    [20 In]          STEAM INLET LINE
 
OPEN                        I                                                                        FROM "B" MAIN
 
I                        61 cm                                            STEAM LINE
 
I                        [24 In]
                                                              I
 
25 cm
 
RX BLDG          HPCI ROOM                                                    [10 In]
                                                              I
 
I
 
POOL                                          I
 
I
 
D    NOTES:
            1. PRESSURE SWITCH ACTUATES ALARM IN CONTROL ROOM WHEN PRESSURE BETWEEN THE INNER RUPTURE DISC AND OUTER
 
RUPTURE DISC IS GREATER THAN 68.9 kPa [10 psig]. ALARM IS FOR INNER RUPTURE DISC LEAK DETECTION.
 
2. REDUNDANT PRESSURE SWITCHES IN EXHAUST STEAM LINE TRIP THE HPCI TURBINE IF PRESSURE IS GREATER THAN 689 kPa [100 psig].
 
3. RUPTURE DISC MAXIMUM DESIGN BURST PRESSURE IS 1034 kPa [150 psig].
 
Figure 1 - Simplified Layout of Quad Cities Station HPCI Turbine Exhaust Steam Line
 
Attachment 2 IN 93-67 August 16, 1993 LIST OF RECENTLY ISSUED
 
NRC INFORMATION NOTICES
 
Information                                    Date of
 
Notice No.              Subject                Issuance    Issued to
 
93-66          Switchover to Hot-Leg          08/16/93  All holders of OLs or CPs
 
Injection Following                        for pressurized water
 
A Loss-of-Coolant                          reactors.
 
Accident in Pres- surized Water Reactors
 
93-65          Reactor Trips Caused            08/13/93-  All holders of OLs or CPs
 
by Breaker Testing                          for nuclear power reactors.
 
with Fault Protection
 
Bypassed
 
93-64            Periodic Testing and            08/12/93  All holders of OLs or CPs
 
Preventive Maintenance                      for nuclear power reactors.
 
of Molded Case Circuit
 
Breakers
 
93-63          Improper Use of Soluble        08/11/93  All holders of OLs or CPs
 
Weld Purge Dam Material                    for nuclear power reactors.
 
93-62          Thermal Stratification          08/10/93  All holders of OLs or CPs
 
of Water in BWR Reactor                    for boiling water reactors.
 
Vessels
 
93-61          Excessive Reactor Coolant      08/09/93  All holders of OLs or CPs
 
Leakage Following A Seal                    for nuclear power reactors.
 
Failure in A Reactor
 
Coolant Pump or Reactor
 
Recirculation Pump
 
93-60          Reporting Fuel Cycle and        08/04/93  All fuel cycle and materials
 
Materials Events to the                    licensees.
 
NRC Operations Center
 
93-59          Unexpected Opening of            07/26/93  All holders of OLs or CPs
 
Both Doors in An                          for nuclear power reactors.
 
Airlock
 
93-58          Nonconservatism in Low-        07/26/93  All holders of OLs or CPs
 
Temperature Overpressure                  for pressurized-water
 
Protection for Pressurized-                reactors.
 
Water Reactors
 
OL = Operating License
 
CP = Construction Permit
 
l
 
IN 93-67 August 16, 1993 This information notice requires no specific action or written response. If
 
you have any questions about the information in this notice, please contact
 
the technical contact listed below or the appropriate Office of Nuclear
 
Reactor Regulation (NRR) project manager.
 
orig /s/'d by CIGrimes/for
 
Brian K. Grimes, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:    Clark Vanderniet, RIII
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachments:
1. Figure 1, "Simplified Layout of Quad Cities
 
Station HPCI Turbine Exhaust Steam Line"
2. List of Recently Issued NRC Information Notices
 
*SEE PREVIOUS CONCURRENCE.
 
OFC      *OEAB:DORS      *TECH:ED          *OGCB:DORS    *DRS:R-III
 
NAME    DSkeen          JMain              PWen          CVanderniet
 
DATE    07/08/93      , 07/08/93          07/14/93      07/14/93 OFC
 
NAME
 
DATE
 
*C:DRS:R-III
 
GWright
 
[ 07/14/93 I *SC:OEAB:DORS
 
RDennig
 
107/15/93
                                              *C/OEAB/DORS
 
AEChaffee
 
07/15/93
                                                              *C:SPLB:DSSA
 
CEMcCracken
 
]07/16/93
                _                        I__              i
 
OFC      *D:DSSA          *C/OGCB:DORS      D/DORS A^r
 
NAME    AThadani        GMarcus            BGrimes  t
 
DATE    07/24/93        07/29/93          0,S/\o/93 V
 
[OFFICIAL RECORD COPY]
DOCUMENT NAME: 93-67.IN
 
\-                                          IN 93-XX
 
July XX, 1993 This information notice requires no specific action or written response. If
 
you have any questions about the information in this notice, please contact
 
the technical contact listed below or the appropriate Office of Nuclear
 
Reactor Regulation (NRR) project manager.
 
Brian K. Grimes, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:      Clark Vanderniet, RIII
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachment:
 
===List of Recently Issued NRC Information Notices===
*SEE PREVIOUS CONCURRENCE.
 
*D:DSSA
 
AThadani
 
07/24/93 OFC      *OEAB:DORS        *TECH:ED        *OGCB:DORS      *DRS:R-III
 
NAME      DSkeen          JMain          PWen            CVanderniet
 
DATE  J07/08/93            07/08/93        07/14/93        07/14/93 OFC      *C:DRS:R-III      *SC:OEAB:DORS  *C/OEAB/DORS    *C:SPLB:DSSA
 
NAME      GWright          RDennig        AEChaffee      CEMcCracken
 
DATE  J07/14/93
        .Y.
 
07/15/93      107/15/93      J07/16/93 OFC        C/OGCB:DORS      D/DORS
 
NAME      GMarcus  ifM    BGrimes T
 
DATE      07/.9/93        07/  /93
[OFFICIAL RECORD COPY]
DOCUMENT NAME: IN93 XX.QC1
 
IN 93-XX
 
July xx, 1993 This information notice requires no specific action or written response. If
 
you have any questions about the information in this notice, please contact
 
one of the technical contacts listed below or the appropriate Office of
 
Nuclear Reactor Regulation (NRR) project manager.
 
Brian K. Grimes, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:        Clark Vanderniet, R-III
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachment:  List of Recently Issued NRC Information Notices
 
*SEE PREVIOUS CONCURRENCE
 
OFFICE  *OEAB:DORS      *TECH:ED        *OGCB:DORS          *DRS:R-III
 
NAME    DSkeen          JMain          l PWen                CVanderniet
 
1'I
 
DATE    07/08/93          07/08/93        07/14/93            07/14/93
  *C:DRS:RIII  *SC:OEAB:DORS    *C:OEAB:DORS      C:SPLBAS*          D: DSS 3q  %
  GWright      RDenning          AChaffee          CEMcCracken        ACThadani
 
07/14/93    [07/15/93          07/15/93        -07/2/f93              07/2A/93 C:OGCB:DORS    D: DORS
 
GHMarcus      BKGrimes
 
07/  /93      07/  /93 DOCUMENT NAME:    QCHPCIIN.WEN    C 5 G-4J -z--l            - 2'J 43--
                                                                    - k k- 9 CJ-
 
IN 93-XX
 
July xx, 1993 This information notice requires no specific action or written response. If
 
you have any questions about the information in this notice, please contact
 
one of the technical contacts listed below or the appropriate Office of
 
Nuclear Reactor Regulation (NRR) project manager.
 
Brian K. Grimes, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:      Clark Vanderniet, R-III
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachment:  List of Recently Issued NRC Information Notices
 
*SEE PREVIOUS CONCURRENCE
 
OFFICE  *OEAB:DORS        *TECH:ED                *OGCB:DORS            *DRS:R-III
 
NAME    DSkeen            JMain                  PWen                  CVanderniet
 
DATE    07/08/93      L, 07/08/93 I_,__. . _,
                                                    07 114/93
                                                      .  . . _I_ __
                                                                  ,      I
 
07/14/93
                                                                            -
  *C:DRS:RIII    S    ODORS                EAB:DORS          C:SPLB:DSSA      D:DSSA
 
GWright        R enn                      afee
 
afaf'              CEMcCracken      ACThadani
 
07/14/93    [        3                07/j</93              07/  /93          07/  /93 C:OGCB:DORS    D:DORS
 
GHMarcus      BKGrimes
 
0
  07/ /93        07/ /93 DOCUMENT NAME: QCHPCIIN.WEN
 
-  E7/14/93                    12:53                787905538417463837
                                                          ?03                                                                            P. 0',
                                                                                                                            IN 93-XX
 
July xx. 1993 This infiIrmation notice requires no specific action noticet please contact
 
or written response. It
 
you have any questions about the information                                            inthis
 
the tech lcal contmct listed                              below        or  the    appropriate      Office of Nuclear
 
Roactor r.gulmtion (NRR) project manager.
 
Brian K. Grimes, Director
 
Division of sOrating RGOM Support
 
Office of Nuclear Reactor Regulation
 
Technic~l contacts                                Clark Vanderniet, R-II1
                                                                    (708) 790-5594 Oavid Skeen NRR
 
(301) 604-1174 Attach            4  nt:        List of Recently Issued NRC Information Notices
 
._
                ,,1
                          *      _
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J                                    \1 IN 93-XX
 
July xx, 1993 This information notice requires no specific action or written response. If
 
you have any questions about the information in this notice, please contact
 
the technical contact listed below or the appropriate Office of Nuclear
 
Reactor Regulation (NRR) project manager.
 
Brian K. Grimes, Director
 
Division of Operating Reactor Support
 
Office of Nuclear Reactor Regulation
 
Technical contacts:        Clark Vanderniet, R-III
 
(708) 790-5594 David Skeen, NRR
 
(301) 504-1174 Attachment:    List of Recently Issued NRC Information Notices
 
*SEE PREVIOUS CONCURRENCE                                I
 
OFFICE  *OEAB:DORS        *TECH:ED        _    i'O
 
_GC W        DRS:R-III
 
NAME    DSkeen            JMain            PWen            CVanderniet
 
DATE    07/08/93          07/08/93          07/ W/93        07/  /93 C:DRS:RIII    SC:OEAB:DORS    C:OEAB:DORS        C:SPLB:DSSA      D:DSSA
 
GWright      RDenning        AChaffee          CEMcCracken      ACThadani
 
07/  /93    J07/  .
 
/93
                              .I
 
07/  /93          07/  /93        07/  /93 C:OGCB:DORS    D:DORS
 
GHMarcus        BKGrimes
 
07/ /93        07/ /93 DOCUMENT NAME: QCHPCIIN.WEN
 
I
 
' >
  OFC      OEAB:DORS      SC/OEAB:DORS  PUB:ADM          C/OEAB:DORS
 
NAME    DSkeen o      RDennig      Tech Ed T7avLY AChaffee


===Attachments:===
[DATE    17 /g/93          / /93       7/P /93            / /93 OFC      OGCB:DORS      C/DRS/R-III  DRS/R-III
1. Figure 1, "Simplified Layout of Quad CitiesStation HPCI Turbine Exhaust Steam Line"2. List of Recently Issued NRC Information Notices Cq~0crcOCd) h r-4 0\TOSUPPRESSIONPOOL1OUTER RUPTURE DISC _____CLOSABLE CHECKCHECK VALVE VALVE IINNER RUPTURE DISC[1 In]240.6 cm[16 in]VENT TOHPCI ROOMSTEAM INLET LINEFROM "B" MAINSTEAM LINELOCKEDOPENIIIIIRX BLDGIIII50.8 cm[20 In]61 cm[24 In]HPCI ROOM25 cm[10 In]D NOTES:1. PRESSURE SWITCH ACTUATES ALARM IN CONTROL ROOM WHEN PRESSURE BETWEEN THE INNER RUPTURE DISC AND OUTERRUPTURE DISC IS GREATER THAN 68.9 kPa [10 psig]. ALARM IS FOR INNER RUPTURE DISC LEAK DETECTION.2. REDUNDANT PRESSURE SWITCHES IN EXHAUST STEAM LINE TRIP THE HPCI TURBINE IF PRESSURE IS GREATER THAN 689 kPa [100 psig].3. RUPTURE DISC MAXIMUM DESIGN BURST PRESSURE IS 1034 kPa [150 psig].Figure 1 -Simplified Layout of Quad Cities Station HPCI Turbine Exhaust Steam Line Attachment 2IN 93-67August 16, 1993 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to93-6693-6593-6493-6393-6293-6193-6093-5993-58Switchover to Hot-LegInjection FollowingA Loss-of-CoolantAccident in Pres-surized Water ReactorsReactor Trips Causedby Breaker Testingwith Fault ProtectionBypassedPeriodic Testing andPreventive Maintenanceof Molded Case CircuitBreakersImproper Use of SolubleWeld Purge Dam MaterialThermal Stratificationof Water in BWR ReactorVesselsExcessive Reactor CoolantLeakage Following A SealFailure in A ReactorCoolant Pump or ReactorRecirculation PumpReporting Fuel Cycle andMaterials Events to theNRC Operations CenterUnexpected Opening ofBoth Doors in AnAirlockNonconservatism in Low-Temperature OverpressureProtection for Pressurized-Water Reactors08/16/9308/13/93-08/12/9308/11/9308/10/9308/09/9308/04/9307/26/9307/26/93All holders of OLs or CPsfor pressurized waterreactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor boiling water reactors.All holders of OLs or CPsfor nuclear power reactors.All fuel cycle and materialslicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor pressurized-waterreactors.OL = Operating LicenseCP = Construction Permit l--IN 93-67August 16, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.orig /s/'d by CIGrimes/forBrian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts:Clark Vanderniet, RIII(708) 790-5594David Skeen, NRR(301) 504-1174


===Attachments:===
NAME    PWen           GWright       CVanderniet
1. Figure 1, "Simplified Layout of Quad CitiesStation HPCI Turbine Exhaust Steam Line"2. List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCE.OFC *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-IIINAME DSkeen JMain PWen CVandernietDATE 07/08/93 , 07/08/93 07/14/93 07/14/93OFC *C:DRS:R-III *SC:OEAB:DORS *C/OEAB/DORS *C:SPLB:DSSANAME GWright I RDennig AEChaffee CEMcCrackenDATE [ 07/14/93 1 07/15/93 07/15/93 ]07/16/93I__ _ iOFC*D:DSSA*C/OGCB:DORSD/DORS A^rNAME AThadani GMarcus BGrimes tDATE 07/24/93 07/29/93 0,S/\o/93 V[OFFICIAL RECORD COPY]DOCUMENT NAME: 93-67.IN
\-IN 93-XXJuly XX, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts: Clark Vanderniet, RIII(708) 790-5594David(301)Skeen, NRR504-1174


===Attachment:===
DATE        / /93         / /93         / /93 OFC      TECH BRANCH    CHF TECH BR    C/OGCB:DORS       D/DORS
List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCE.*D:DSSAAThadani07/24/93OFC *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-IIINAME DSkeen JMain PWen CVandernietDATE J 07/08/93 07/08/93 07/14/93 07/14/93OFC *C:DRS:R-III *SC:OEAB:DORS *C/OEAB/DORS *C:SPLB:DSSANAME GWright RDennig AEChaffee CEMcCrackenDATE J 07/14/93 07/15/93 107/15/93 J07/16/93.Y.OFCC/OGCB:DORSD/DORSNAME GMarcus ifM BGrimes TDATE 07/.9/93 07/ /93[OFFICIAL RECORD COPY]DOCUMENT NAME: IN93 XX.QC1 IN 93-XXJuly xx, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below or the appropriate Office ofNuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts:Clark Vanderniet, R-III(708) 790-5594David Skeen, NRR(301) 504-1174


===Attachment:===
NAME                                l GMarcus        l BGrimes
List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCEOFFICE *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-IIINAME DSkeen JMain l PWen CVandernietDATE07/08/9307/08/9307/14/9307/14/931'I*C:DRS:RIII *SC:OEAB:DORS *C:OEAB:DORS C:SPLBAS* D: DSS 3q %GWright RDenning AChaffee CEMcCracken ACThadani07/14/93 [07/15/93 07/15/93 -07/2/f93 07/2A/93C:OGCB:DORSD: DORSGHMarcus BKGrimes07/ /93 07/ /93DOCUMENT NAME: QCHPCIIN.WENC 5 G-4J -z--l -2'J 4 3-- -k k- 9 C J-
IN 93-XXJuly xx, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactone of the technical contacts listed below or the appropriate Office ofNuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts:Clark(708)Vanderniet, R-III790-5594David Skeen, NRR(301) 504-1174


===Attachment:===
DATE        / /93         / /93         / /93         1   / /93     l
List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCEOFFICE *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-IIINAME DSkeen JMain PWen CVandernietDATE07/08/9307/08/9307 114/9307/14/93L, _, I_,__ _ .., __ ...I_ I -*C:DRS:RIII S ODORS EAB:DORS C:SPLB:DSSA D:DSSAGWright R enn afaf' afee CEMcCracken ACThadani07/14/93 [ 3 07/j</93 07/ /93 07/ /93C:OGCB:DORSD:DORSGHMarcus BKGrimes07/ /93 07/ /930DOCUMENT NAME: QCHPCIIN.WEN
-E7/14/9312:53 ?03 787905538417463837P. 0',This infiyou havethe techRoactorIN 93-XXJuly xx. 1993 Irmation notice requires no specific action or written response. Itany questions about the information in this noticet please contactlcal contmct listed below or the appropriate Office of Nuclearr.gulmtion (NRR) project manager.Brian K. Grimes, DirectorDivision of sOrating RGOM SupportOffice of Nuclear Reactor RegulationTechnic~l contactsClark Vanderniet, R-II1(708) 790-5594Oavid Skeen NRR(301) 604-1174Attach4nt: List of Recently Issued NRC Information Notices/._ _ *,,1'SEL PR -.IUUb 6UNCUUMM6C,OFFIC D _ *TECH:,ED -I _ I RNAME _ JGnMain PI_. .,I -- '^A j"IR na jai4I 7/1k01.%0J//Y//93I1UATI I uJ 1 b I W ._ II nF&-flIA I C:PBDS :ISS I ----.n J T TVcr P. rAn
* Motwrn r nAs WDgRI C.SPLB*DSSAD :DSSA_ICh ouf I 1NNI I I I;rn n I= -- 1 --.-. -T II 1Atn"^"4^"I ji 1%V, famrEIaCrackenACThadani _1OI-lqn 0, 7/ R/9M3..~07~11 9 93 07/ /93 -- 107/ /193 -IQl l 193 107/ /93--:_ _r _r.nnr 'f lRSD:DORSus BK rimes-.. ..- _ L4Y.IIuL)OCUME NA ML: QUMrLun.w~J'14 JUL 93 B: 5uLETd lN11 211HM DUN411 b0S T ,z ES:90 t 5os->X-L0LM1 b0S IQ&#xa3; J\1IN 93-XXJuly xx, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contacts:Clark(708)Vanderniet, R-III790-5594David Skeen, NRR(301) 504-1174


===Attachment:===
[OFFICIAL RECORD COPY]
List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCEIOFFICE *OEAB:DORS *TECH:ED _ _GC i'O W DRS:R-IIINAME DSkeen JMain PWen CVandernietDATE07/08/9307/08/9307/ W/9307/ /93C:DRS:RIII SC:OEAB:DORS C:OEAB:DORS C:SPLB:DSSA D:DSSAGWright RDenning AChaffee CEMcCracken ACThadani07/ /93 J07/ /93 07/ /93 07/ /93 07/ /93..IC:OGCB:DORSD:DORSGHMarcus BKGrimes07/ /93 07/ /93DOCUMENT NAME: QCHPCIIN.WEN I' >OFC OEAB:DORS SC/OEAB:DORS PUB:ADM C/OEAB:DORSNAME DSkeen o RDennig Tech Ed T7av LY AChaffee[DATE 17/g/93 / /93 7/P /93 / /93OFC OGCB:DORS C/DRS/R-III DRS/R-IIINAME PWen GWright CVandernietDATE / /93 / /93 / /93OFC TECH BRANCH CHF TECH BR C/OGCB:DORS D/DORSNAME l GMarcus l BGrimesDATE / /93 / /93 / /93 1 / /93 l[OFFICIAL RECORD COPY]DOCUMENT NAME: IN93 XX.QC1}}
  DOCUMENT NAME: IN93 XX.QC1}}


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Latest revision as of 04:24, 24 November 2019

Bursting of High Pressure Coolant Injection Steam Line Rupture Discs Injures Plant Personnel
ML031070135
Person / Time
Site: Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, 05000349, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant  Entergy icon.png
Issue date: 08/16/1993
From: Grimes B
Office of Nuclear Reactor Regulation
To:
References
IN-93-067, NUDOCS 9308100248
Download: ML031070135 (14)
v • d • e


U -AU

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 August 16, 1993 NRC INFORMATION NOTICE 93-67: BURSTING OF HIGH PRESSURE COOLANT INJECTION

STEAM LINE RUPTURE DISCS INJURES PLANT

PERSONNEL

Addressees

nuclear power

All holders of operating licenses or construction permits for

reactors.

Purpose

information

The U.S. Nuclear Regulatory Commission (NRC) is issuing thissteam driven

notice to remind addressees of the hazards associated with

injection (HPCI)

coolant injection systems such as the high pressure coolant at BWRs and the

system and the reactor core isolation cooling (RCIC) system will

auxiliary feedwater system at PWRs. It is expected that recipients and consider

review the information for applicability to their facilities X

actions, as appropriate, to avoid similar problems. However, suggestions therefore, no

contained in this information notice are not NRC requirements;

specific action or written response is required.

Background

the HPCI turbine

The purpose of HPCI steam exhaust rupture discs is to protect event if the normal

casing and associated exhaust piping from an overpressure Quad Cities Station, exhaust path to the suppression pool becomes blocked. At

in series with a

two 40.6-cm [16-inch] stainless steel discs are installed sensor

6.4-cm [2.5-inch] spacer between them to allow for a pressure

while serving no control function, instrumentation line. The pressure sensor, to alert the

actuates an alarm in the control room at 68.9 kPa [10 psig]

of the HPCI

operators that the inner disc is leaking. The normal range The HPCI high

exhaust steam pressure is 172 to 207 kPa [25 to 30 psig].-

and is sensed by

exhaust pressure turbine trip setpoint is 689 kPa [100 psig] piping

the section of

pressure sensors located downstream from where piping. The

containing the rupture discs branches off from the exhaust vertically over the

section of piping containing the rupture discs is mounted

greater than

turbine exhaust and vents directly to the HPCI room. Pressure inner disc to rupture

1034 kPa [150 psig] in the exhaust line will cause the

steam into the HPCI room.

and impact the outer disc, releasing

Description of Circumstances

Edison

During a quarterly inservice test of the HPCI pump at the Commonwealth line rupture

9, 1993, the exhaust steam

Quad Cities Station, Unit 1, on June

9308100248 F QrRi

IN 93-67 August 16, 1993 discs burst, releasing steam into the HPCI room, burning, and slightly

contaminating, five workers. The rupture discs burst within one second after

the turbine was started. Fire doors between the Unit 1 and Unit 2 HPCI rooms

were blown off their hinges into the Unit 2 HPCI room. Both sets of double

doors that are part of the secondary containment boundary were also blown

open. The floor latch on the inner containment door was bent; the outer doors

were also slightly damaged, but were repaired, closed and sealed approximately

35 minutes after the event. The steam release was terminated by automatic

isolation of the steam supply line on high HPCI turbine area temperature about

20 seconds into the event.

Discussion

Upon investigating the event, the licensee determined that water had

accumulated in the turbine casing because the drain system level switches for

the Unit 1 HPCI system had failed. In April 1992, the licensee performed a

reliability-centered maintenance study which recommended the level switches be

included in the preventive maintenance program but the recommendation had not

been acted on at the time of the event. The Unit 2 HPCI drain system level

switches were also found to be inoperable.

The slug of water created during the HPCI turbine roll passed from the turbine

casing to the vertical exhaust line and compressed the air in the 40.6 cm

[16 inch] line containing the rupture discs. The resulting pressure pulse

caused the inner rupture disc to burst, which impacted the outer disc as

designed and caused it to burst as well. The exhaust line pressure sensors, located in the horizontal 61 cm [24 inch] exhaust line that tees off from the

vertical 40.6 cm [16 inch] rupture disc line, did not detect a high pressure

(see Figure 1). The pressure switches were within tolerance and should have

immediately isolated the steam supply upon sensing a high exhaust pressure

before the rupture discs burst. The fact that a high exhaust line pressure

was not detected indicates two possible causes for the disc rupture. Either

the inner rupture disc was degraded and burst at lower-than-design pressure, or the pressure pulse actually exceeded the design pressure and caused the

disc to burst, relieving the exhaust line pressure before the downstream

pressure sensors detected a high pressure condition.

While inspection of the rupture discs did not reveal any degradation from

corrosion or aging, the vendor, Black Sivalls & Bryson, Inc, stated that the

discs are warranted for one year of service under normal conditions. The HPCI

and RCIC rupture discs at Quad Cities Station had been in service for 20 years

and were not part of any scheduled inspection or preventive maintenance

program. When consulted about the event, the vendor advised against using the

spare discs in the plant storeroom because they were purchased at the same

time as the failed discs. The licensee later replaced the failed discs with

new units. Before this event, the licensee recently replaced a HPCI rupture

disc during a refueling outage at the Dresden Station, a plant similar to Quad

Cities, after finding a crack in the disc during an inspection. The rupture

discs were inspected at the Dresden station as part of an enhancement to the

preventive maintenance program that was recommended by a reliability-centered

analysis.

I I

IN 93-67 August 16, 1993 The steam injured five workers, four of whom were participating in the HPCI

pump surveillance test. The fifth, and m6st severely. injured worker was a

health physics technician in the room on routine rounds, who was not aware of

the danger posed by the surveillance test. The test procedure contained no

specific guidance on room occupancy. Interviews with the workers revealed

that they had performed the surveillance in the past and were familiar with

the process. This familiarity may have led to a relaxed attitude toward

personal safety. The workers stated that during previous surveillances they

sometimes evacuated the room before rolling the turbine, or stood near the

doors to be ready to escape. The licensee made no routine announcement over

the plant paging system to alert plant personnel before the HPCI-turbine

start, and the workers were not prepared for the turbine to start.

A lack of constant communication between the workersand the control room may

have contributed to the personnel injuries. If a control room operator had

been in contact with the workers in the HPCI room during the turbine roll, the

workers would have been aware of the impending turbine start and, after start, the steam supply might have been manually-isolated or the turbine manually

tripped before the automatic isolation caused by the high area temperatureoin

the HPCI room.

When the Unit 1 HPCI rupture disc failure caused the fire doors to be blown

off their hinges and into the Unit 2 HPCI room, one of the doors impacted a

pipe hanger in the room and moved it 5.1 centimeters [2 inches]. If the steam

release had resulted from a high energy line break from the inlet side of the

HPCI steam line instead of the exhaust line, the damage to the Unit 2 HPCI

system could have been more severe. While high energy line breaks have been

analyzed for safety systems at all plants, the doors to rooms containing high

energy steam lines may not have been included in the analysis. For example, at Duane Arnold Energy Center, the licensee discovered that while the HPCI and

RCIC rooms were qualified for pressures of 26.2 kPa [3.8 psig], the doors

between these rooms and the reactor building would yield at 6.9 kPa [1 psig].

The licensee for the Quad Cities Station will implement a preventive

maintenance schedule for both the HPCI and RCIC rupture discs and the level

switches. The licensee will review the surveillance test procedure and

evaluate the missile hazard created by the fire doors. The licensee replaced

the rupture discs for the Unit 2 HPCI and RCIC systems with new ones after the

event at Unit 1 and is considering burst testing the removed discs to

determine if they are degraded.

IN 93-67 August 16, 1993 This information notice requires no specific action

you have any questions about the information in this or written response. If

the technical contact listed below or the appropriate notice, please contact

Reactor Regulation (NRR) project manager. Office of Nuclear

Brian K. Grim s, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, RIII

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachments:

1. Figure 1, "Simplified Layout of Quad Cities

Station HPCI Turbine Exhaust Steam Line"

2. List of Recently Issued NRC Information Notices

Cq~

0cr 1 cO

Cd)h r-

4

0 OUTER RUPTURE DISC _____

\TO VENT TO

HPCI ROOM

INNER RUPTURE DISC

[1 In]

2 40.6 cm

[16 in]

CLOSABLE CHECK

CHECK VALVE VALVE I

SUPPRESSION

50.8 cm

LOCKED I [20 In] STEAM INLET LINE

OPEN I FROM "B" MAIN

I 61 cm STEAM LINE

I [24 In]

I

25 cm

RX BLDG HPCI ROOM [10 In]

I

I

POOL I

I

D NOTES:

1. PRESSURE SWITCH ACTUATES ALARM IN CONTROL ROOM WHEN PRESSURE BETWEEN THE INNER RUPTURE DISC AND OUTER

RUPTURE DISC IS GREATER THAN 68.9 kPa [10 psig]. ALARM IS FOR INNER RUPTURE DISC LEAK DETECTION.

2. REDUNDANT PRESSURE SWITCHES IN EXHAUST STEAM LINE TRIP THE HPCI TURBINE IF PRESSURE IS GREATER THAN 689 kPa [100 psig].

3. RUPTURE DISC MAXIMUM DESIGN BURST PRESSURE IS 1034 kPa [150 psig].

Figure 1 - Simplified Layout of Quad Cities Station HPCI Turbine Exhaust Steam Line

Attachment 2 IN 93-67 August 16, 1993 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

93-66 Switchover to Hot-Leg 08/16/93 All holders of OLs or CPs

Injection Following for pressurized water

A Loss-of-Coolant reactors.

Accident in Pres- surized Water Reactors

93-65 Reactor Trips Caused 08/13/93- All holders of OLs or CPs

by Breaker Testing for nuclear power reactors.

with Fault Protection

Bypassed

93-64 Periodic Testing and 08/12/93 All holders of OLs or CPs

Preventive Maintenance for nuclear power reactors.

of Molded Case Circuit

Breakers

93-63 Improper Use of Soluble 08/11/93 All holders of OLs or CPs

Weld Purge Dam Material for nuclear power reactors.

93-62 Thermal Stratification 08/10/93 All holders of OLs or CPs

of Water in BWR Reactor for boiling water reactors.

Vessels

93-61 Excessive Reactor Coolant 08/09/93 All holders of OLs or CPs

Leakage Following A Seal for nuclear power reactors.

Failure in A Reactor

Coolant Pump or Reactor

Recirculation Pump

93-60 Reporting Fuel Cycle and 08/04/93 All fuel cycle and materials

Materials Events to the licensees.

NRC Operations Center

93-59 Unexpected Opening of 07/26/93 All holders of OLs or CPs

Both Doors in An for nuclear power reactors.

Airlock

93-58 Nonconservatism in Low- 07/26/93 All holders of OLs or CPs

Temperature Overpressure for pressurized-water

Protection for Pressurized- reactors.

Water Reactors

OL = Operating License

CP = Construction Permit

l

IN 93-67 August 16, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

orig /s/'d by CIGrimes/for

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, RIII

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachments:

1. Figure 1, "Simplified Layout of Quad Cities

Station HPCI Turbine Exhaust Steam Line"

2. List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE.

OFC *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-III

NAME DSkeen JMain PWen CVanderniet

DATE 07/08/93 , 07/08/93 07/14/93 07/14/93 OFC

NAME

DATE

  • C:DRS:R-III

GWright

[ 07/14/93 I *SC:OEAB:DORS

RDennig

107/15/93

  • C/OEAB/DORS

AEChaffee

07/15/93

  • C:SPLB:DSSA

CEMcCracken

]07/16/93

_ I__ i

OFC *D:DSSA *C/OGCB:DORS D/DORS A^r

NAME AThadani GMarcus BGrimes t

DATE 07/24/93 07/29/93 0,S/\o/93 V

[OFFICIAL RECORD COPY]

DOCUMENT NAME: 93-67.IN

\- IN 93-XX

July XX, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, RIII

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachment:

List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE.
  • D:DSSA

AThadani

07/24/93 OFC *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-III

NAME DSkeen JMain PWen CVanderniet

DATE J07/08/93 07/08/93 07/14/93 07/14/93 OFC *C:DRS:R-III *SC:OEAB:DORS *C/OEAB/DORS *C:SPLB:DSSA

NAME GWright RDennig AEChaffee CEMcCracken

DATE J07/14/93

.Y.

07/15/93 107/15/93 J07/16/93 OFC C/OGCB:DORS D/DORS

NAME GMarcus ifM BGrimes T

DATE 07/.9/93 07/ /93

[OFFICIAL RECORD COPY]

DOCUMENT NAME: IN93 XX.QC1

IN 93-XX

July xx, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, R-III

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

OFFICE *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-III

NAME DSkeen JMain l PWen CVanderniet

1'I

DATE 07/08/93 07/08/93 07/14/93 07/14/93

  • C:DRS:RIII *SC:OEAB:DORS *C:OEAB:DORS C:SPLBAS* D: DSS 3q  %

GWright RDenning AChaffee CEMcCracken ACThadani

07/14/93 [07/15/93 07/15/93 -07/2/f93 07/2A/93 C:OGCB:DORS D: DORS

GHMarcus BKGrimes

07/ /93 07/ /93 DOCUMENT NAME: QCHPCIIN.WEN C 5 G-4J -z--l - 2'J 43--

- k k- 9 CJ-

IN 93-XX

July xx, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, R-III

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE

OFFICE *OEAB:DORS *TECH:ED *OGCB:DORS *DRS:R-III

NAME DSkeen JMain PWen CVanderniet

DATE 07/08/93 L, 07/08/93 I_,__. . _,

07 114/93

. . . _I_ __

, I

07/14/93

-

  • C:DRS:RIII S ODORS EAB:DORS C:SPLB:DSSA D:DSSA

GWright R enn afee

afaf' CEMcCracken ACThadani

07/14/93 [ 3 07/j</93 07/ /93 07/ /93 C:OGCB:DORS D:DORS

GHMarcus BKGrimes

0

07/ /93 07/ /93 DOCUMENT NAME: QCHPCIIN.WEN

- E7/14/93 12:53 787905538417463837

?03 P. 0',

IN 93-XX

July xx. 1993 This infiIrmation notice requires no specific action noticet please contact

or written response. It

you have any questions about the information inthis

the tech lcal contmct listed below or the appropriate Office of Nuclear

Roactor r.gulmtion (NRR) project manager.

Brian K. Grimes, Director

Division of sOrating RGOM Support

Office of Nuclear Reactor Regulation

Technic~l contacts Clark Vanderniet, R-II1

(708) 790-5594 Oavid Skeen NRR

(301) 604-1174 Attach 4 nt: List of Recently Issued NRC Information Notices

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J \1 IN 93-XX

July xx, 1993 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Clark Vanderniet, R-III

(708) 790-5594 David Skeen, NRR

(301) 504-1174 Attachment: List of Recently Issued NRC Information Notices

  • SEE PREVIOUS CONCURRENCE I

OFFICE *OEAB:DORS *TECH:ED _ i'O

_GC W DRS:R-III

NAME DSkeen JMain PWen CVanderniet

DATE 07/08/93 07/08/93 07/ W/93 07/ /93 C:DRS:RIII SC:OEAB:DORS C:OEAB:DORS C:SPLB:DSSA D:DSSA

GWright RDenning AChaffee CEMcCracken ACThadani

07/ /93 J07/ .

/93

.I

07/ /93 07/ /93 07/ /93 C:OGCB:DORS D:DORS

GHMarcus BKGrimes

07/ /93 07/ /93 DOCUMENT NAME: QCHPCIIN.WEN

I

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OFC OEAB:DORS SC/OEAB:DORS PUB:ADM C/OEAB:DORS

NAME DSkeen o RDennig Tech Ed T7avLY AChaffee

[DATE 17 /g/93 / /93 7/P /93 / /93 OFC OGCB:DORS C/DRS/R-III DRS/R-III

NAME PWen GWright CVanderniet

DATE / /93 / /93 / /93 OFC TECH BRANCH CHF TECH BR C/OGCB:DORS D/DORS

NAME l GMarcus l BGrimes

DATE / /93 / /93 / /93 1 / /93 l

[OFFICIAL RECORD COPY]

DOCUMENT NAME: IN93 XX.QC1


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