The U.S. Nuclear Regulatory Commission is in the process of rescinding or revising guidance and policies posted on this webpage in accordance with Executive Order 14151 Ending Radical and Wasteful Government DEI Programs and Preferencing, and Executive Order 14168 Defending Women From Gender Ideology Extremism and Restoring Biological Truth to the Federal Government. In the interim, any previously issued diversity, equity, inclusion, or gender-related guidance on this webpage should be considered rescinded that is inconsistent with these Executive Orders.

Event Notification Report for July 1, 1999

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           06/30/1999 - 07/01/1999

                              ** EVENT NUMBERS **

35811  35862  35880  35881  35882  35883  35884  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35811       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: GINNA                    REGION:  1  |NOTIFICATION DATE: 06/10/1999|
|    UNIT:  [1] [] []                 STATE:  NY |NOTIFICATION TIME: 13:56[EDT]|
|   RXTYPE: [1] W-2-LP                           |EVENT DATE:        05/11/1999|
+------------------------------------------------+EVENT TIME:        13:35[EDT]|
| NRC NOTIFIED BY:  MCCOY                        |LAST UPDATE DATE:  06/30/1999|
|  HQ OPS OFFICER:  CHAUNCEY GOULD               +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |JOHN CARUSO          R1      |
|10 CFR SECTION:                                 |                             |
|AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION    |                             |
|NLCO                     TECH SPEC LCO A/S      |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| BOTH DIESEL GENERATORS DECLARED INOPERABLE                                   |
|                                                                              |
| During the review (on 6/10/99 @ 1330) of an event in which the "A"  Diesel   |
| Generator (D/G) output breaker failed to close during periodic testing, it   |
| was discovered that the plant had operated for a period of time with both    |
| required D/Gs inoperable.  Based on the identified failure mode, the  "A"    |
| D/G breaker was in an inoperable state since the last time it was tripped.   |
| This occurred following the performance of periodic testing on 5/11/99 @     |
| 1148.  On 5/11/99 @ 1334, the  "B"  D/G was declared inoperable for the      |
| performance of periodic testing, which resulted in both D/Gs being           |
| inoperable and the plant entering a 3.0.3 TS LCO action statement.           |
| Therefore, during the periodic testing of the "B"  D/G, there would have     |
| been an inability to automatically respond to an event coincident with a     |
| loss of offsite power.  The "B" D/G was immediately returned to service      |
| following the test.  The "A" D/G was restored to operable status on 6/9/99.  |
| The licensee notified the NRC Resident Inspector.                            |
|                                                                              |
| * * * UPDATE AT 1519 ON 6/30/99 BY DOUG PETERSEN TO JOLLIFFE * * *           |
|                                                                              |
| The licensee has concluded that the date and time of inoperability is when   |
| the "A" D/G output breaker to safeguards bus #14 failed to close (1007 on    |
| 6/8/99).  The "A" D/G was declared operable on 6/9/99, and the time of       |
| inoperability is within the allowable LCO time frame. Therefore, no          |
| reportable event occurred and the licensee desires to retract this event.    |
|                                                                              |
| During troubleshooting, the breaker was successfully closed at the bus       |
| cubicle more than 20 times on 6/8/99 and 6/9/99 without any adjustment of    |
| the breaker and without another failure.  The apparent cause of the breaker  |
| failure is attributed to a slight misalignment of the tripper bar on the     |
| breaker.  However, potential effects of bus vibration, temperature,          |
| lubrication drying, and the randomness of the breaker failure does not       |
| provide firm evidence of the specific time the breaker became inoperable.    |
| There is no firm evidence to believe the discrepancy existed prior to        |
| 6/8/99.  Therefore, in accordance with the industry guidance provided in     |
| NUREG-1022, Revision 1, it should be assumed the discrepancy occurred at the |
| time of its discovery.  The licensee notified the NRC Resident Inspector.    |
|                                                                              |
| The NRC Operations Officer notified the R1DO Larry Doerflein.                |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|General Information or Other                     |Event Number:   35862       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| REP ORG:  ABB COMBUSTION ENGINEERING           |NOTIFICATION DATE: 06/25/1999|
|LICENSEE:  ABB COMBUSTION ENGINEERING           |NOTIFICATION TIME: 16:34[EDT]|
|    CITY:  WINDSOR                  REGION:  1  |EVENT DATE:        06/25/1999|
|  COUNTY:                            STATE:  CT |EVENT TIME:             [EDT]|
|LICENSE#:                        AGREEMENT:  N  |LAST UPDATE DATE:  06/30/1999|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |GLENN MEYER          R1      |
|                                                |VERN HODGE (via fax) NRR     |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  IAN RICKARD                  |                             |
|  HQ OPS OFFICER:  BOB STRANSKY                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|CCCC 21.21               UNSPECIFIED PARAGRAPH  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| 10CFR PART 21 REPORT REGARDING ABB COMBUSTION ENGINEERING 4KV VACUUM         |
| BREAKERS                                                                     |
|                                                                              |
| The following text is excerpted from a facsimile received in the NRC         |
| Operations Center:                                                           |
|                                                                              |
| "The defect concerns ABB 1200A 4KV Vacuum Breakers delivered to Baltimore    |
| Gas and Electric Company's (BG&E's) Calvert Cliffs Nuclear Power Plant       |
| (CCNPP).  Specifically, the defect concerns the breaker performing a trip    |
| free operation when a close signal is received by the breaker.  This defect  |
| results in the breaker failing to remain in the closed position.  The defect |
| could lead to non-conservative failure of not starting certain plant         |
| equipment upon demand such as an Emergency Core Cooling Pump."               |
|                                                                              |
| * * * UPDATE AT 1613 ON 06/30/99 BY VIRGIL PAGGEN TO JOLLIFFE * * *          |
|                                                                              |
| The above 10CFR Part 21 Report was submitted to the NRC via ABB Combustion   |
| Engineering Letter #LD-99-035, dated 06/25/99.  The following is an update   |
| to the above 10CFR Part 21 Report via ABB Combustion Engineering Letter      |
| #LD-99-039, dated 06/30/99, Same Subject.                                    |
|                                                                              |
| The activity for which this report is being filed is the use of ABB 1200A    |
| 4KV Vacuum Breakers in an application where the breaker is normally open and |
| must close on demand.  This defect applies only to BG&E's CCNPP.             |
|                                                                              |
| The defect identified is associated with the use of the ABB 1200A 4KV Vacuum |
| Breaker only in applications where the breaker must close on demand.  The    |
| defect was detected during site testing of the breaker during installation   |
| into CCNPP.  During this test, a close signal was applied to the breaker and |
| the breaker tripped free (i.e., failed to remain in the closed position).    |
|                                                                              |
| These breakers are intended for both normally open and normally closed       |
| operation.  In some applications, the breaker must close upon demand.  This  |
| may be for electrical distribution applications or component control         |
| applications (e.g., start an Emergency Core Cooling pump).  Demands can be   |
| automated (e.g., by ESFAS) or based on manual operator demands.  If the      |
| breaker does not remain closed when demanded (i.e., trips free), the safety  |
| function cannot be performed.  This breaker is intended for use in multiple  |
| redundant safety divisions. Multiple redundant divisions could be affected   |
| by this defect.                                                              |
|                                                                              |
| The defect applies only to ABB 1200A 4KV Vacuum Breakers delivered to CCNPP. |
| Thirty-seven (37) of these breakers were delivered to CCNPP.   ABB           |
| Combustion Engineering understands that several of these breakers have been  |
| installed at CCNPP, however, none are installed in any application that      |
| requires a close on demand function.                                         |
|                                                                              |
| The NRC Operations Officer notified the R1DO Larry Doerflein and NRR Vern    |
| Hodge (via fax).                                                             |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35880       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: SEABROOK                 REGION:  1  |NOTIFICATION DATE: 06/30/1999|
|    UNIT:  [1] [] []                 STATE:  NH |NOTIFICATION TIME: 11:50[EDT]|
|   RXTYPE: [1] W-4-LP                           |EVENT DATE:        06/30/1999|
+------------------------------------------------+EVENT TIME:        09:05[EDT]|
| NRC NOTIFIED BY:  DANA MORRELL                 |LAST UPDATE DATE:  06/30/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |LAWRENCE DOERFLEIN   R1      |
|10 CFR SECTION:                                 |                             |
|NLTR                     LICENSEE 24 HR REPORT  |                             |
|APRE 50.72(b)(2)(vi)     OFFSITE NOTIFICATION   |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| 24 HOUR REPORT - DEAD SEAL FOUND                                             |
|                                                                              |
| The licensee notified the National Marine Fisheries and the NRC Resident     |
| Inspector that they discovered a dead seal in the plant intake structure     |
| during a routine inspection.                                                 |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35881       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: OCONEE                   REGION:  2  |NOTIFICATION DATE: 06/30/1999|
|    UNIT:  [1] [2] [3]               STATE:  SC |NOTIFICATION TIME: 17:59[EDT]|
|   RXTYPE: [1] B&W-L-LP,[2] B&W-L-LP,[3] B&W-L-L|EVENT DATE:        06/30/1999|
+------------------------------------------------+EVENT TIME:        17:22[EDT]|
| NRC NOTIFIED BY:  RANDY TODD                   |LAST UPDATE DATE:  06/30/1999|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |PAUL FREDRICKSON     R2      |
|10 CFR SECTION:                                 |                             |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Cold Shutdown    |0        Cold Shutdown    |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|3     N          Y       100      Power Operation  |100      Power Operation  |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - Certain accident scenarios could cause pressurization of Low Pressure      |
| Injection and Rx Bldg Spray Systems -                                        |
|                                                                              |
| During investigation of a valve leak observed during a test on Unit 1, it    |
| was discovered that there is a possibility that certain accident scenarios   |
| could cause pressurization of certain portions of the Low Pressure Injection |
| (LPI) and Reactor Building Spray (RBS) Systems above values previously       |
| evaluated.                                                                   |
|                                                                              |
| Specifically, following a small break LOCA, the LPI System is still taking   |
| suction from the Borated Water Storage Tank (BWST) when the system is        |
| aligned with the LPI Pump 'A' discharging to both injection headers through  |
| the crossover piping in preparation for realigning suction to the Reactor    |
| Building Emergency Sump.  At this time, it is possible to pressurize the     |
| suction piping of the idle LPI Pump 'B' and RBS Pump 'B'.  This can occur    |
| because the LPI Pump 'B' minimum flow recirculation line is connected        |
| downstream of the pump discharge check valve or as a result of leakage       |
| through the pump discharge check valve.  A small amount of fluid would flow  |
| through the recirculation line until the pressure in the pump suction piping |
| is equal to the pressure in the cross-connected LPI discharge headers.       |
| (Procedural details would prevent this problem from affecting Train 'A'.)    |
|                                                                              |
| This pressure could be in excess of the capability of certain valve          |
| operators to reposition process valves. Among the affected valves is #LP-20, |
| the RB Emergency Sump Train 'B' isolation valve.                             |
|                                                                              |
| When nearing depletion of the BWST inventory, the Emergency Operating        |
| Procedure calls for opening both RB Emergency Sump isolation valves (#LP-19  |
| on Train 'A' and #LP-20 on Train 'B').                                       |
|                                                                              |
| It was also recognized that #LP-19, in the redundant flow path, must be      |
| considered vulnerable to a random single failure.                            |
|                                                                              |
| Therefore, at 1722 on 06/30/99, Oconee Site Managers concluded that #LP-20   |
| must be considered inoperable for use in this specific system configuration. |
| This configuration is only used during certain small break LOCAs which       |
| require that the LPI and High Pressure Injection (HPI) Systems be placed in  |
| the "piggy-back" configuration where the LPI pumps supply flow to the HPI    |
| pump suctions.  In addition, this failure scenario only applies to the       |
| limited spectrum of small breaks that do not result in initiation of Reactor |
| Building Spray.                                                              |
|                                                                              |
| Because this inoperablity only affects the HPI-LPI "piggy-back" Train 'B'    |
| flow path, the operating units (Units 2 & 3) entered Tech Spec 3.5.2,        |
| Condition C, which has a 72 hour action statement.  The main corrective      |
| action is implementation of a system alignment change which will create a    |
| vent path to the Reactor Building using the Reactor Building Spray Train 'B' |
| piping.  This will prevent the possibility of pressurizing the piping at     |
| #LP-20 and eliminate the potential for this problem.  The procedure changes  |
| are in progress and the implementation is expected to occur on night shift   |
| tonight (06/30/99).  In addition, operators on shift will receive awareness  |
| training on the new configuration as it is implemented.  Corresponding       |
| changes to the Emergency Operating Procedure                                 |
| will be implemented prior to exiting the Tech Spec 3.5.2.C action statement. |
| Affected Periodic Test, Maintenance, and Instrument Procedures have been     |
| placed on administrative hold until they can be revised.                     |
|                                                                              |
| Unit 1 is currently in Mode 5 (Cold Shutdown) in a Refueling Outage          |
| preparing to enter Mode 4.  These alignment changes will be incorporated on  |
| Unit 1, as appropriate, during plant start-up.                               |
|                                                                              |
| The analysis of this issue is continuing, and the potential exists that      |
| further analysis or testing may allow retraction                             |
| of this notification.  If not, further details will be provided in the LER   |
| that will be submitted to the NRC.                                           |
|                                                                              |
| The licensee notified the NRC Resident Inspector.                            |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Transportation                                   |Event Number:   35882       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| REP ORG:  SYNCOR INTERNATIONAL CORP            |NOTIFICATION DATE: 06/30/1999|
|LICENSEE:  SYNCOR INTERNATIONAL CORP            |NOTIFICATION TIME: 18:00[EDT]|
|    CITY:  NASHVILLE                REGION:  2  |EVENT DATE:        06/30/1999|
|  COUNTY:                            STATE:  TN |EVENT TIME:        12:00[EDT]|
|LICENSE#:                        AGREEMENT:  Y  |LAST UPDATE DATE:  06/30/1999|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |PAUL FREDRICKSON     R2      |
|                                                |LINDA HOWELL         R4      |
+------------------------------------------------+SUSAN SHANKMAN       NMSS    |
| NRC NOTIFIED BY:  SCOTT LANGFORD               |DON COOL             NMSS    |
|  HQ OPS OFFICER:  DICK JOLLIFFE                |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|BAB2 20.2201(a)(1)(ii)   LOST/STOLEN LNM>10X    |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - OVERDUE SHIPMENT OF MEDICAL RADIOPHARMACEUTICALS (IODINE-131) -            |
|                                                                              |
| AT 1630 ON 06/25/99, A PACKAGE OF MEDICAL RADIOPHARMACEUTICALS (0.9          |
| MILLICURIES OF IODINE-131) WAS SHIPPED BY CAR/TRUCK VIA ASSOCIATED COURIERS  |
| FROM SYNCOR INTERNATIONAL CORP, ST LOUIS, MO TO SYNCOR, NASHVILLE, TN.  THE  |
| SHIPMENT WAS SCHEDULED TO ARRIVE IN NASHVILLE AT 1200 ON 06/26/99.  THE      |
| SHIPMENT IS OVERDUE.  ASSOCIATED COURIERS IS ATTEMPTING TO LOCATE THE        |
| PACKAGE.  MR LANGFORD PLANS TO NOTIFY THE STATE OF TN.                       |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Other Nuclear Material                           |Event Number:   35883       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| REP ORG:  QUEST X TECHNOLOGIES, GUAM           |NOTIFICATION DATE: 06/30/1999|
|LICENSEE:  QUEST X TECHNOLOGIES, GUAM           |NOTIFICATION TIME: 19:13[EDT]|
|    CITY:  GUAM                     REGION:     |EVENT DATE:        06/30/1999|
|  COUNTY:                            STATE:     |EVENT TIME:             [EST]|
|LICENSE#:                        AGREEMENT:  N  |LAST UPDATE DATE:  06/30/1999|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |LINDA HOWELL         R4      |
|                                                |SUSAN SHANKMAN       NMSS    |
+------------------------------------------------+EPA (BY FAX)                 |
| NRC NOTIFIED BY:  CUMMINGS & HICKMAN           |                             |
|  HQ OPS OFFICER:  DICK JOLLIFFE                |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NINF                     INFORMATION ONLY       |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - PACKAGE OF IRIDIUM - 192 WITHOUT SHIPPING PAPERS LOCATED IN GUAM -         |
|                                                                              |
| TOM BIRKAMEYER, CHIEF OF SAFETY, CONTINENTAL AIRLINES, GUAM AIRPORT,         |
| RECEIVED A PACKAGE OF IRIDIUM - 192 ABOUT TWO MONTHS AGO AND STORED IT IN    |
| THE HAZARDOUS MATERIALS AREA AT THE AIRPORT IN GUAM.  THE SHIPPING PAPERS    |
| ARE NOT AVAILABLE AND THE SHIPPER AND RECEIVER ARE UNKNOWN.                  |
|                                                                              |
| RECENTLY, PERSONNEL AT QUEST X TECHNOLOGIES (JAHA CUMMINGS & WALT HICKMAN)   |
| TOOK POSSESSION OF THE PACKAGE AND PLACED IT IN A LOCKED STORAGE SHED IN     |
| GUAM.  THE PACKAGE IS A SMALL DRUM, TYPE 'A' PACKAGE WITH THE FOLLOWING      |
| PARTIALLY OBSCURED MARKINGS:  RADIATION SYMBOL, RADIOACTIVE YELLOW 3, SOLID  |
| FORM, UN-2982 (NUMBER MAY BE INCORRECT), AND "ENGLAND".  QUEST PERSONNEL     |
| MEASURED THE PACKAGE WITH A GM SURVEY INSTRUMENT AND OBTAINED MAXIMUM        |
| READINGS OF 0.2 MR/HR AT THE SURFACE OF THE PACKAGE.                         |
|                                                                              |
| QUEST PERSONNEL CALLED THE NRC TO REQUEST INSTRUCTIONS ON WHAT TO DO WITH    |
| THE PACKAGE.                                                                 |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   35884       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: SUSQUEHANNA              REGION:  1  |NOTIFICATION DATE: 07/01/1999|
|    UNIT:  [1] [] []                 STATE:  PA |NOTIFICATION TIME: 04:56[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        07/01/1999|
+------------------------------------------------+EVENT TIME:        02:08[EDT]|
| NRC NOTIFIED BY:  R. PEAL                      |LAST UPDATE DATE:  07/01/1999|
|  HQ OPS OFFICER:  WILLIAM POERTNER             +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |LAWRENCE DOERFLEIN   R1      |
|10 CFR SECTION:                                 |                             |
|ACCS 50.72(b)(1)(iv)     ECCS INJECTION         |                             |
|ARPS 50.72(b)(2)(ii)     RPS ACTUATION          |                             |
|AESF 50.72(b)(2)(ii)     ESF ACTUATION          |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     A/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| ECCS INJECTION, RPS ACTUATION, AND ESF ACTUATION.                            |
|                                                                              |
| Susquehanna Unit 1 experienced a Reactor Scram due to a neutron monitoring   |
| upscale trip signal.  Preliminary indication is that the 'C' outboard MSIV   |
| went closed, causing the high neutron flux that tripped the reactor.  The    |
| other three steam lines experienced high steam flow resulting in the closure |
| of all the steam line isolation valves.   As a result of the Reactor Scram   |
| with MSIV closure, water level dropped to approximately minus 46 inches on   |
| wide range level instrumentation.  Level was restored to 35 inches using     |
| high pressure coolant injection (HPCI) and reactor core isolation cooling    |
| (RCIC).  Reactor pressure peaked at 1048 psig prior to the scram.  All       |
| control rods inserted and safety relief valves were cycled to control        |
| pressure.                                                                    |
|                                                                              |
| The licensee entered a 12 hour to cold shutdown LCO at 02:51 EDT due to      |
| suppression pool temperature exceeding 120 degrees.  Suppression pool        |
| temperature is presently 134 degrees.                                        |
|                                                                              |
| The licensee has notified the NRC resident inspector.                        |
+------------------------------------------------------------------------------+


Page Last Reviewed/Updated Thursday, March 25, 2021