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Event Notification Report for July 26, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           07/25/2001 - 07/26/2001

                              ** EVENT NUMBERS **

38168  38169  38170  38171  38172  38173  

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|Fuel Cycle Facility                              |Event Number:   38168       |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 07/25/2001|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 05:28[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        07/24/2001|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        12:30[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  07/25/2001|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |PATRICK HILAND       R3      |
|  DOCKET:  0707002                              |C.W. (BILL) REAMER   NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  SISLER                       |                             |
|  HQ OPS OFFICER:  CHAUNCEY GOULD               |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| 24 - HOUR 91-01 BULLETIN - LOSS OF ONE CONTROL OF THE DOUBLE CONTINGENCY     |
| PRINCIPLE                                                                    |
|                                                                              |
| On 7-24-01 at 1230 hours, a process operator in the X-330 Building           |
| discovered a NCSA-0330_004.A05 noncompliance with cell 29-4-6.  Cell 29-4-6  |
| is a shutdown cell at a UF6 negative and was buffered above 14 psia.  Over   |
| time the pressure decrease to 13.96 psia.  This violated NCSA-0330_004.A05   |
| requirement #8 resulting in a loss of one control (moderation) of the double |
| contingency principle.  Mass (second control) was maintained throughout the  |
| event.                                                                       |
|                                                                              |
| NCSA-0330_004.A05 requirement #8 states in part, "Within 8 hours after       |
| cascade equipment shutdown (motor turned off) and with the system at a UF6   |
| negative, the system shall be pressurized with plant air or N2 buffer at >   |
| 14 psia, unless the equipment is undergoing maintenance, pre and post        |
| maintenance troubleshooting, being evacuated or treated."                    |
|                                                                              |
| Buffer pressure was increased to greater than 14 psia at 1300 hours.         |
| Moderation control was re-established for cell 29-4-6.                       |
|                                                                              |
| The safety significance of this event is low. There is no deposit in this    |
| cell.  The worst case would be contamination on process surfaces exposed to  |
| process gas prior to shutdown and buffering.                                 |
|                                                                              |
| This event is reportable per NRC BL 91-01 as a loss of one control of the    |
| double contingency principle.                                                |
|                                                                              |
| SAFETY SIGNIFICANCE OF EVENTS:                                               |
|                                                                              |
| The safety significance of this event is low.  There is no deposit in the    |
| cell (thus is less than a safe mass for an H/U=4 and the cell is isolated    |
| from the cascade.  The mass in the cell is controlled by virtue of the fact  |
| that the shutdown cell is isolated from the cascade which is also shutdown.  |
| If the unbuffered condition were permitted to continue for a long period of  |
| time, the H/U could eventually reach a maximum of 4.  However, since any     |
| material in the cell is less than the safe mass H/U ratio, a criticality     |
| would not occur even if the H/U reached the maximum through the loss of a    |
| buffer.                                                                      |
|                                                                              |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW            |
| CRITICALITY COULD OCCUR):                                                    |
|                                                                              |
| The cell would need to be unisolated and UF6 introduced to create a deposit. |
| That deposit would then have to become sufficiently moderated in order for a |
| criticality to occur.                                                        |
|                                                                              |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.):     |
|                                                                              |
| The parameters controlled are mass and moderation.                           |
|                                                                              |
| ESTIMATED AMOUNT,  ENRICHMENT,  FORM OF LICENSED MATERIAL (INCLUDE PROCESS   |
| LIMIT AND % WORST CASE OF CRITICAL MASS):                                    |
|                                                                              |
| There is no deposit in this cell.  Worst case would be contamination on      |
| process surfaces exposed to process gas prior to shutdown and buffering.     |
|                                                                              |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION   |
| OF THE FAILURES OR DEFICIENCIES                                              |
|                                                                              |
| The NCS control is a dry air buffer >14 psia.  Over time the pressure        |
| decreased to 13.96 psia.                                                     |
|                                                                              |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:   |
|                                                                              |
| Buffer pressure was increased to greater than 14 psia at 1300 hours.         |
| Control was re-established.                                                  |
|                                                                              |
| The NRC Resident Inspector was notified along with the DOE Representative.   |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38169       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PALISADES                REGION:  3  |NOTIFICATION DATE: 07/25/2001|
|    UNIT:  [1] [] []                 STATE:  MI |NOTIFICATION TIME: 11:51[EDT]|
|   RXTYPE: [1] CE                               |EVENT DATE:        07/25/2001|
+------------------------------------------------+EVENT TIME:        08:31[EDT]|
| NRC NOTIFIED BY:  ROBERT VINCENT               |LAST UPDATE DATE:  07/25/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |PATRICK HILAND       R3      |
|10 CFR SECTION:                                 |                             |
|ADEG 50.72(b)(3)(ii)(A)  DEGRADED CONDITION     |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| ADDITIONAL INDICATIONS DISCOVERED ON CRDM HOUSINGS                           |
|                                                                              |
| "Nondestructive examination of welds on control rod drive mechanism pressure |
| housings has resulted in the discovery of additional indications to those    |
| reported earlier (reference event notification numbers 38083, 38103 and      |
| 38111). The weld examinations are being conducted as part of an              |
| extent-of-condition evaluation resulting from a discovery on June 21, 2001   |
| of a through-wall indication on CRDM 21. Extent-of-condition and cause       |
| evaluation is ongoing. Regular updates with NRC Region III and NRR will      |
| continue."                                                                   |
|                                                                              |
| The licensee stated that no further notifications will be made to the NRC    |
| Operations Center regarding this issue.                                      |
|                                                                              |
| The NRC resident inspector has been informed of this notification by the     |
| licensee.                                                                    |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38170       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: GRAND GULF               REGION:  4  |NOTIFICATION DATE: 07/25/2001|
|    UNIT:  [1] [] []                 STATE:  MS |NOTIFICATION TIME: 13:12[EDT]|
|   RXTYPE: [1] GE-6                             |EVENT DATE:        07/25/2001|
+------------------------------------------------+EVENT TIME:        11:16[CDT]|
| NRC NOTIFIED BY:  STEPHEN HUMPHRIES            |LAST UPDATE DATE:  07/25/2001|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |GARY SANBORN         R4      |
|10 CFR SECTION:                                 |VICTOR DRICKS        OPA     |
|APRE 50.72(b)(2)(xi)     OFFSITE NOTIFICATION   |JOE HOLONICH         IRO     |
|                                                |JOHN TAPPERT         NRR     |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| OFFSITE NOTIFICATION REGARDING ACTUATION OF THE CIVIL DEFENSE SIRENS WHEN NO |
| ACTUAL EMERGENCY EXISTED                                                     |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "During an emergency preparedness drill, a local agency (Claiborne County    |
| Civil Defense) activated the civil defense sirens.  The sirens should not    |
| have been sounded for the drill.  This report is being made as an event that |
| for which notification to other agencies has been or will be made            |
| (50.72(b)(2)(xi)).  Plant operation was not affected, and no release of      |
| radioactivity occurred."                                                     |
|                                                                              |
| The licensee stated that the sirens sounded briefly (for probably less than  |
| 1 minute).  At the time of this event notification, the site had not         |
| received any calls from the public.                                          |
|                                                                              |
| It was reported that Claiborne County Civil Defense notified local radio     |
| stations and requested them to make an announcement stating that the         |
| actuation of the sirens was unintentional and that there was no emergency.   |
| Claiborne County Civil Defense also plans to issue a press release.          |
| Applicable State, local, and other government agencies were involved in the  |
| exercise and are aware of the event.  The licensee notified the acting NRC   |
| resident inspector (Peter Alter).                                            |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38171       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: BROWNS FERRY             REGION:  2  |NOTIFICATION DATE: 07/25/2001|
|    UNIT:  [] [2] []                 STATE:  AL |NOTIFICATION TIME: 15:31[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4,[3] GE-4           |EVENT DATE:        07/25/2001|
+------------------------------------------------+EVENT TIME:        10:46[CDT]|
| NRC NOTIFIED BY:  TIM GOLDEN                   |LAST UPDATE DATE:  07/25/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |MALCOLM WIDMANN      R2      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|AESF 50.72(b)(3)(iv)(A)  VALID SPECIF SYS ACTUAT|                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     A/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC TURBINE TRIP/REACTOR SCRAM DURING TESTING                          |
|                                                                              |
| "During performance of CIV [combined intercept valve] testing per 2-OI-47    |
| section 6.7, the unit 2 reactor scrammed due to Turbine Generator Load       |
| reject. Emergency control procedure EOI-1 was entered due to low reactor     |
| water level and high reactor pressure. PCIS [primary containment isolation   |
| system] groups 2,3, 6 and 8 were received, A, B and C SBGT [standby gas      |
| treatment] trains started and A CREV [control room emergency ventilation]    |
| started as expected. Initial indications show that some Safety Relief Valves |
| (SRVs) momentarily opened during the pressure spike following closure of the |
| main turbine control and stop valves. The unit remains in hot shutdown (mode |
| 3) to continue troubleshooting the exact cause of the EHC [electrohydraulic  |
| control] logic control system causing the main turbine trip.                 |
|                                                                              |
| "This event is reportable as a 4 hour ENS report per 10CFR50.72(b)(2)(iv)(B) |
| as 'Any event or condition that results in actuation of the reactor          |
| protection system (RPS) when the reactor is critical except when the         |
| actuation results from and is part of a pre-planned sequence during testing  |
| or reactor Operation.'  And an 8 hour report per 10CFR50.72(b)(3)(iv)(A) as  |
| 'Any event or condition that results in valid actuation of any of the        |
| systems listed in paragraph (b)(3)(iv)(8), ie: RPS'.                         |
|                                                                              |
| "This is also reportable per 10CFR50.73 (a)(2)(iv)(A) for the above          |
| conditions as a 60 day written report."                                      |
|                                                                              |
| The NRC resident inspector has been informed of this event by the licensee.  |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38172       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PEACH BOTTOM             REGION:  1  |NOTIFICATION DATE: 07/25/2001|
|    UNIT:  [] [3] []                 STATE:  PA |NOTIFICATION TIME: 17:59[EDT]|
|   RXTYPE: [2] GE-4,[3] GE-4                    |EVENT DATE:        07/25/2001|
+------------------------------------------------+EVENT TIME:        15:24[EDT]|
| NRC NOTIFIED BY:  STEVE TANNER                 |LAST UPDATE DATE:  07/25/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |JOHN WHITE           R1      |
|10 CFR SECTION:                                 |                             |
|AIND 50.72(b)(3)(v)(D)   ACCIDENT MITIGATION    |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|3     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| HPCI SYSTEM DECLARED INOPERABLE                                              |
|                                                                              |
| "Unit 3 high pressure coolant injection (HPCI) system inoperable. This       |
| constitutes an 8-hour ENS report in accordance with 10 CFR 50.72(b)(3)(v)    |
| and 10 CFR 50.36(c)(1)(ii)(A). The unit 3 HPCI system was considered         |
| inoperable while aligned to the suppression pool. This condition was         |
| determined during the performance of an approved system operating procedure  |
| that would ensure the suction line of the HPCI system is filled and vented   |
| while aligned to the suppression pool. Adequate suction pressure could not   |
| be developed during the performance of the procedure, therefore Operations   |
| placed the auxiliary oil pump in pull-to-lock to prevent automatic starts of |
| the system.                                                                  |
|                                                                              |
| "Unit 3 HPCI was aligned to the suppression pool in order to comply with     |
| Technical Specification Section 3.3.5.1, Required Action D.2.2.  Required    |
| Action D.2.2 was performed due to a failure of the condensate storage tank   |
| (CST) level switches. The failed CST level switches caused an unplanned      |
| automatic swap of the HPCI suction line from the CST to the suppression      |
| pool.                                                                        |
|                                                                              |
| "The problem is being investigated and the cause is unknown at this time."   |
|                                                                              |
| The NRC resident inspector has been informed of this event by the licensee.  |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   38173       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: SOUTH TEXAS              REGION:  4  |NOTIFICATION DATE: 07/25/2001|
|    UNIT:  [1] [2] []                STATE:  TX |NOTIFICATION TIME: 19:02[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        07/25/2001|
+------------------------------------------------+EVENT TIME:        10:11[CDT]|
| NRC NOTIFIED BY:  WAYNE HARRISON               |LAST UPDATE DATE:  07/25/2001|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |GARY SANBORN         R4      |
|10 CFR SECTION:                                 |                             |
|AUNA 50.72(b)(3)(ii)(B)  UNANALYZED CONDITION   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          Y       100      Power Operation  |100      Power Operation  |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| POTENTIAL TO DRAIN AFW STORAGE TANK DURING PLANT FLOODING SCENARIO           |
|                                                                              |
| "STPNOC Engineering identified a condition outside the station's design      |
| basis that has been determined to be reportable under 10CFR50.73(a)(2)(ii)   |
| as an unanalyzed condition that significantly degraded plant safety.         |
| Notification is required by 10CFR50.72(b)(3)(ii)(B).                         |
|                                                                              |
| "During review of design calculations, a new internal flooding condition was |
| identified that could have resulted in depletion of the AFW Storage Tank to  |
| the point where the plant would not be able to transition from AFW to RHR as |
| designed. Each of STP's four trains of AFW is enclosed in its own            |
| water-tight compartment directly beneath its associated MFW line RCB         |
| penetration. Operator response to a main feedline break includes isolation   |
| of the faulted steam generator, including AFW. If the MFW break is           |
| postulated to occur in the MFW penetration area above AFW, the AFW cubicle   |
| beneath the break will flood. In the case of the D train steam-driven AFW,   |
| the water level will submerge the turbine-driven AFW pump, its trip/throttle |
| valve and AFW isolation valves in about 6 to 30 minutes, depending on break  |
| size. As a consequence of the accident, the submerged motor-operated valves  |
| are assumed to fail as-is, supplying steam to the turbine-driven pump and    |
| allowing AFW flow. In addition, the analysis assumes the single failure of   |
| one unsubmerged steam supply isolation valve. The steam-driven pump will     |
| continue to function while submerged and continue to take suction from the   |
| AFWST and expel it out the break. Unless the pump is secured, its continued  |
| operation could accelerate the depletion of the AFWST to the point that the  |
| plant would not be able to transition from AFW to RHR as designed. This      |
| condition affects only the D train steam-driven AFW. Trains A, B, and C are  |
| motor driven and can be readily secured at their power source if necessary.  |
|                                                                              |
| "Compensatory action is being taken to implement a temporary modification to |
| allow operator action to isolate the AFW supply to the steam-driven AFW pump |
| at the AFWST."                                                               |
|                                                                              |
| The NRC resident inspector has been informed of this condition by the        |
| licensee.                                                                    |
+------------------------------------------------------------------------------+