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Event Notification Report for September 11, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           09/08/2000 - 09/11/2000

                              ** EVENT NUMBERS **

37266  37268  37299  37300  37301  37302  37303  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37266       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: NINE MILE POINT          REGION:  1  |NOTIFICATION DATE: 08/28/2000|
|    UNIT:  [] [2] []                 STATE:  NY |NOTIFICATION TIME: 20:17[EDT]|
|   RXTYPE: [1] GE-2,[2] GE-5                    |EVENT DATE:        08/28/2000|
+------------------------------------------------+EVENT TIME:        16:30[EDT]|
| NRC NOTIFIED BY:  RICHARD LANGE                |LAST UPDATE DATE:  09/08/2000|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |PETE ESELGROTH       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   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| INOPERABILITY OF THE PASS AND BOTH DIVISION I/II H2O2 MONITORING SYSTEMS     |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "On 8/28/2000, at 1630, [the Division] I and [II] Hydrogen/Oxygen (H2O2)     |
| Containment Monitoring Systems were declared inoperable.  The Division I     |
| system was declared inoperable on 8/28/2000, at 0818, for planned            |
| maintenance.  Subsequently, the Division II system was declared inoperable   |
| due to a failed channel check."                                              |
|                                                                              |
| "In addition, the Post Accident Sampling System (PASS) was previously        |
| declared inoperable.  With the PASS and both Division I/II H2O2 Monitoring   |
| Systems inoperable, this event is reportable in accordance with 10 CFR       |
| 50.72(b)(2)(iii)(D)."                                                        |
|                                                                              |
| "Also, on 8/28/2000, at 1905, the Division I H2O2 Monitor was restored to    |
| operable [status] following completion of planned maintenance."              |
|                                                                              |
| The licensee stated that the unit remained in a 30-day limiting condition    |
| for operation (LCO) and that a 7-day shutdown LCO was exited when the        |
| Division I H2O2 Monitor was restored to operable status.                     |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
|                                                                              |
| ***** UPDATE/RETRACTION AT 0024 ON 09/08/00 FROM ANTHONY PETRELLI TO LEIGH   |
| TROCINE *****                                                                |
|                                                                              |
| The licensee is retracting this event notification.  The following text is a |
| portion of a facsimile received from the licensee:                           |
|                                                                              |
| "On 08/28/00, 1630 EDT, Nine Mile Point Unit 2 reported that Divisions 1 and |
| 2 of the Hydrogen/Oxygen (H2/02) Containment Monitoring Systems were         |
| declared inoperable under Event Number 37266."                               |
|                                                                              |
| "[The licensee is] retracting that notification based on the fact that the   |
| Division 1 H2/O2 monitoring system was removed from service as part of       |
| planned maintenance in accordance with approved procedures and plant         |
| Technical [Specifications].  During planned maintenance, a discrepancy was   |
| found in the Division 1 H2/O2 system.  Subsequent evaluation indicated that  |
| the condition discovered would not have prevented the system from performing |
| its safety function if called upon.  Therefore, this event is not            |
| reportable."                                                                 |
|                                                                              |
| The licensee notified the NRC resident inspector.  The NRC operations        |
| officer notified the R1DO (Dimitriadis).                                     |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   37268       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 08/29/2000|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 01:36[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        08/28/2000|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        15:29[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  09/09/2000|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |MELVYN LEACH         R3      |
|  DOCKET:  0707002                              |JOSEPHINE PICCONE    NMSS    |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  RICK LARSON                  |                             |
|  HQ OPS OFFICER:  BOB STRANSKY                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| 24-HOUR NRC BULLETIN 91-01 REPORT                                            |
|                                                                              |
| "On 8/28/00 at 1529, during implementation of NCSA 0705_076 (Inadvertent     |
| Containers) a concern was raised about the maximum distance of spray from a  |
| leak from a pressurized pipe. Calculations were reevaluated and the          |
| corrected spray distance for the system in question resulted in a distance   |
| of 106 feet. This new distance for the system in question is greater than    |
| the original implementation distance of 15 feet, which the NCSA had          |
| previously predicted for the entire X-705. This is considered a loss of one  |
| control. The control considered lost is control #2 which states in part,     |
| 'When unattended all potential inadvertent containers shall be:              |
| -modified to prevent unsafe accumulation                                     |
| -covered to prevent the in-leakage of spilled materials                      |
| -oriented to prevent an unsafe accumulation                                  |
|                                                                              |
| "The PSS(Plant Shift Superintendent) directed the facility custodian to      |
| enter an anomalous condition. The system in question was previously shut     |
| down prior to recalculation of the spray distance. The same equipment        |
| remains shutdown until compliance with NCSA 0705_076 can be determined.      |
|                                                                              |
| "SAFETY SIGNIFICANCE OF EVENTS:                                              |
|                                                                              |
| "Safety significance is low. The resulting situation is conservatively being |
| identified as a violation of one control contained in NCSA 0705_076 which    |
| requires that all potential inadvertent containers utilized in the X-705 be  |
| modified, covered, or oriented to prevent an unsafe accumulation. However,   |
| since the system in question maintained its physical integrity and thus no   |
| uranium bearing material was involved the safety significance of this event  |
| is low.                                                                      |
|                                                                              |
| "POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO[S] OF HOW           |
| CRITICALITY COULD OCCUR):                                                    |
|                                                                              |
| "If a sufficient amount of uranium bearing material had leaked, spilled,     |
| splashed from the micro filtration system and the resuming material          |
| accumulated on/in an inadvertent container, an unsafe geometry could have    |
| resulted. If the leaking solution had contained a sufficient amount of       |
| uranium, the resulting configuration could have been sufficient for a        |
| criticality to occur. it should be noted that the allowed safe geometry and  |
| volume limits established in NCSA 0705-076 are based on optimally moderated  |
| solution which contains uranium enriched to 100 wt% U235.                    |
|                                                                              |
| "CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC):     |
|                                                                              |
| "The parameter which was violated during this upset was maintaining          |
| geometry/volume controls regarding potential accumulation points available   |
| on/in nearby inadvertent containers.                                         |
|                                                                              |
| "ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS    |
| LIMIT AND % WORST CASE OF CRITICAL MASS):                                    |
|                                                                              |
| "No uranium-bearing material was actually involved in the upset.             |
|                                                                              |
| "NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION  |
| OF THE FAILURES OR DEFICIENCIES:                                             |
|                                                                              |
| "NCSA 0705_076 takes credit for the physical integrity of systems which      |
| contain uranium bearing materials. NCSA 0705_076 also takes Credit that      |
| unsafe volume/geometry containers are either modified, covered or oriented   |
| while in areas where uranium bearing material can leak, spill or spray to    |
| prevent an unsafe configuration from resulting in the event of a leak. The   |
| administrative control #2 was not being followed for the new area identified |
| where uranium bearing materials can leak, spill or spray. The resulting      |
| situation is conservatively being identified as a violation of the           |
| administrative control in NCSA 0705_076.                                     |
|                                                                              |
| "CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:  |
|                                                                              |
| "The PSS (Plant Shift Superintendent) directed the facility custodian to     |
| enter an anomalous condition. The system in question was previously shut     |
| down prior to recalculation of the spray distance. The same equipment will   |
| remain shutdown until NCS (Nuclear Criticality Safety) can assist in         |
| determination of operability of that system and compliance with NCSA         |
| 0705_076."                                                                   |
|                                                                              |
| The NRC resident inspector has been informed of this event.                  |
|                                                                              |
| * * * UPDATE 1021EDT ON 9/9/00 FROM JEFF CASTLE TO S. SANDIN * * *           |
|                                                                              |
| "9/9/00 - Update #1 - An engineering evaluation (EVAL-PS-2000-0415) of the   |
| system and pumps associated with implementation of NCSA_0705_076 identified  |
| that the spray distances used to originally determine the reportability of   |
| this event were excessive. The original distance (15 feet) used to implement |
| this NCSA has since been identified to adequately bound the credible         |
| scenarios for solutions spraying from various systems in the X-705. This     |
| issue would not have been reportable based on the newly acquired information |
| as a result of the recent technical review."                                 |
|                                                                              |
| The NRC resident inspector and DOE site representative have been informed.   |
| Notified R3DO(Shear).                                                        |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37299       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: HATCH                    REGION:  2  |NOTIFICATION DATE: 09/08/2000|
|    UNIT:  [1] [] []                 STATE:  GA |NOTIFICATION TIME: 15:39[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        09/08/2000|
+------------------------------------------------+EVENT TIME:        13:30[EDT]|
| NRC NOTIFIED BY:  PAUL UNDERWOOD               |LAST UPDATE DATE:  09/08/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MARK LESSER          R2      |
|10 CFR SECTION:                                 |                             |
|AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION    |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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                                   
+------------------------------------------------------------------------------+
| HIGH PRESSURE COOLANT INJECTION (HPCI) SYSTEM DECLARED INOPERABLE            |
|                                                                              |
| "At 1330 on 09/08/00, HPCI Flow Controller, 1E41-R612, was observed to be    |
| exhibiting erratic indication of flow. Flow indication was oscillating from  |
| 0 to >500 gpm with HPCI in its standby condition. Investigation is           |
| continuing."                                                                 |
|                                                                              |
| The NRC resident inspector will be informed of this event by the licensee.   |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Fuel Cycle Facility                              |Event Number:   37300       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT   |NOTIFICATION DATE: 09/09/2000|
|   RXTYPE: URANIUM ENRICHMENT FACILITY          |NOTIFICATION TIME: 10:21[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER                   |EVENT DATE:        09/08/2000|
|           6903 ROCKLEDGE DRIVE                 |EVENT TIME:        20:00[EDT]|
|           BETHESDA, MD 20817    (301)564-3200  |LAST UPDATE DATE:  09/09/2000|
|    CITY:  PIKETON                  REGION:  3  +-----------------------------+
|  COUNTY:  PIKE                      STATE:  OH |PERSON          ORGANIZATION |
|LICENSE#:  GDP-2                 AGREEMENT:  N  |GARY SHEAR           R3      |
|  DOCKET:  0707002                              |                             |
+------------------------------------------------+                             |
| NRC NOTIFIED BY:  JEFF CASTLE                  |                             |
|  HQ OPS OFFICER:  STEVE SANDIN                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NBNL                     RESPONSE-BULLETIN      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| 24-HOUR NRC BULLETIN 91-01 REPORT INVOLVING SAFETY SYSTEM ACTUATION          |
|                                                                              |
| "On 9/8/2000 at 2000 hours a safety system actuation occurred in the X344    |
| building.  Autoclave #4 was in Mode II 'Heating'  when the High Condensate   |
| Level Shutoff safety system actuated.  Per TSR 2.1.3.7, the autoclave was    |
| placed in Mode VII  'Shutdown', a mode in which the High Condensate level    |
| Shutoff system is not required, and declared inoperable. This is being       |
| reported as a valid safety system actuation.  An engineering evaluation has  |
| been initiated to review the system conditions that surrounded the actuation |
| of the safety system."                                                       |
|                                                                              |
| Operations notified both the NRC resident inspector and DOE site             |
| representative.                                                              |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|General Information or Other                     |Event Number:   37301       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| REP ORG:  CROW BUTTE RESOURCES                 |NOTIFICATION DATE: 09/10/2000|
|LICENSEE:  CROW BUTTE RESOURCES                 |NOTIFICATION TIME: 09:52[EDT]|
|    CITY:  CRAWFORD                 REGION:  4  |EVENT DATE:        09/09/2000|
|  COUNTY:                            STATE:  NE |EVENT TIME:        18:30[CDT]|
|LICENSE#:  SUA1534               AGREEMENT:  Y  |LAST UPDATE DATE:  09/10/2000|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |WILLIAM JOHNSON      R4      |
|                                                |DANIEL GILLEN        NMSS    |
+------------------------------------------------+E. WILLIAM BRACH     NMSS    |
| NRC NOTIFIED BY:  MIKE GRIFFIN                 |                             |
|  HQ OPS OFFICER:  STEVE SANDIN                 |                             |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          N/A                   |                             |
|10 CFR SECTION:                                 |                             |
|NINF                     INFORMATION ONLY       |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+------------------------------------------------------------------------------+

                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| CONDITION OF LICENSEE REPORT INVOLVING A MONITOR WELL EXCURSION              |
|                                                                              |
| RESULTS OF SAMPLES REPORTED AT 1830MDT ON 9/9/00 CONFIRMED THAT FOUR         |
| PARAMETER  SINGLE UPPER CONTROL LIMITS (UCLs) AND THE FIFTH MULTIPLE UCL     |
| WERE EXCEEDED IN SHALLOW MONITOR WELL SM6-12.                                |
|                                                                              |
| PARAMETERS   /UCLs/    MEASURED VALUES[UNITS] ARE:                           |
|                                                                              |
| SODIUM                      /36/                         43                  |
| [milligrams/liter]                                                           |
| SULFATE                    /19/                        85                    |
| [milligrams/liter]                                                           |
| CHLORIDES                /7/                         55                      |
| [milligrams/liter]                                                           |
| CONDUCTIVITY   /736/                       910                               |
| [microMHOs/cm]                                                               |
| ALKALINITY           /290/                        294                        |
| [milligrams/liter]                                                           |
|                                                                              |
| THE LICENSEE WILL DISCUSS POSSIBLE CORRECTIVE ACTIONS WITH THEIR HYDROLOGIST |
| AND GEOLOGISTS  IN THE MORNING.  THIS COULD INCLUDE DRILLING SAMPLE TEST     |
| WELLS.                                                                       |
|                                                                              |
| THE LICENSEE WILL NOTIFY THE NEBRASKA DEPARTMENT OF ENVIRONMENTAL QUALITY    |
| AND THE NRC PROJECT MANAGER.                                                 |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37302       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: WATTS BAR                REGION:  2  |NOTIFICATION DATE: 09/10/2000|
|    UNIT:  [1] [] []                 STATE:  TN |NOTIFICATION TIME: 19:55[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        09/10/2000|
+------------------------------------------------+EVENT TIME:        16:28[EDT]|
| NRC NOTIFIED BY:  BENJAMIN HUNT                |LAST UPDATE DATE:  09/10/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |MARK LESSER          R2      |
|10 CFR SECTION:                                 |                             |
|AESF 50.72(b)(2)(ii)     ESF ACTUATION          |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC START OF TURBINE DRIVEN AUXILIARY FEEDWATER PUMP                   |
|                                                                              |
| "At 1628 hours on 9/10/2000, with the reactor in Mode 5 for a refueling      |
| outage; Watts Bar engineering reported preliminary results of an             |
| investigation into the inadvertent start of the turbine driven auxiliary     |
| feedwater pump. At approximately 0200 hours on 9/10/2000, operators found    |
| the auxiliary feedwater pump operating without the presence of start signal. |
| Steam generator level was being provided by previously started motor driven  |
| AFW pumps and operations secured the turbine driven pump. There was no       |
| impact from the event on plant refueling preparations and no safety          |
| consequence.                                                                 |
|                                                                              |
| "There was no valid AFW start signal in place at the time and plant          |
| conditions were not such that a signal was required. Engineering was         |
| requested to investigate the event and identified that at about the time of  |
| the pump start, maintenance technicians were working in an adjacent part of  |
| this rack where the relay believed to have been involved in the actuation is |
| located. A review of the circuit determined that an inadvertent bump of the  |
| relay could result in the start of the pump and the independent actuation of |
| turbine driven AFW steam generator level control valves. Based on this       |
| information, Operations concluded that based on the preliminary engineering  |
| information an invalid start of an ESF train had occurred and declared the   |
| event reportable under 10 CFR 50.72(b)(2)(ii) and 50.73(a)(2)(iv).           |
|                                                                              |
| "At the time the pump was found in operation it was known that there was no  |
| valid start signal, but it was thought that the issue involved only a single |
| component. Because other S/G level maneuvers were in process independent of  |
| the AFW start, it was not recognized at the time that the level control      |
| valves were involved in the event. After the preliminary engineering review, |
| it was concluded that although it was an invalid actuation, the event        |
| involved a train level actuation and was, therefore, reportable."            |
|                                                                              |
| The NRC resident inspector has been informed of this event by the licensee.  |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   37303       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: CALVERT CLIFFS           REGION:  1  |NOTIFICATION DATE: 09/10/2000|
|    UNIT:  [1] [] []                 STATE:  MD |NOTIFICATION TIME: 23:02[EDT]|
|   RXTYPE: [1] CE,[2] CE                        |EVENT DATE:        09/10/2000|
+------------------------------------------------+EVENT TIME:        21:23[EDT]|
| NRC NOTIFIED BY:  ROBERT PACE                  |LAST UPDATE DATE:  09/11/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |ANTHONY DIMITRIADIS  R1      |
|10 CFR SECTION:                                 |                             |
|AESF 50.72(b)(2)(ii)     ESF ACTUATION          |                             |
|ARPS 50.72(b)(2)(ii)     RPS 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 Standby      |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| AUTOMATIC REACTOR TRIP DUE TO CLOSURE OF MAIN STEAM ISOLATION VALVES         |
|                                                                              |
| An automatic reactor trip/turbine trip occurred due to the spurious closure  |
| of both main steam isolation valves (MSIVs). The spurious MSIV closure was   |
| the result of a failed logic module in the engineered safety features        |
| actuation system (ESFAS). All control rods inserted following the trip, and  |
| all systems functioned as expected. The auxiliary feedwater (AFW) system     |
| automatically started as designed following the trip. The unit is currently  |
| stable in Hot Standby with decay heat being removed through steam released   |
| via the steam generator atmospheric dump valves. Steam generator water       |
| levels are being maintained by the AFW system.                               |
|                                                                              |
| The licensee anticipates that replacement of the logic module and            |
| establishment of decay heat removal via the main condenser will occur within |
| the next few hours. The NRC resident inspector has been informed of this     |
| event by the licensee. The licensee reported that nearby residents have      |
| contacted emergency services regarding the noises caused by the steam        |
| release through the atmospheric dump valves. The licensee plans to make a    |
| press release regarding this event.                                          |
|                                                                              |
| * * * UPDATE 0428EDT ON 9/11/00 FROM ROBERT PACE TO S. SANDIN * * *          |
|                                                                              |
| The MSIVs were reopened and the main condenser placed back in service at     |
| 0420EDT for decay heat removal.  Preparations are underway to restore one    |
| main feedwater pump and secure the AFW system.  Notified R1DO(Dimitriadis).  |
+------------------------------------------------------------------------------+