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Event Notification Report for July 25, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           07/24/2000 - 07/25/2000

                              ** EVENT NUMBERS **

37152  37163  37184  

!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
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|Power Reactor                                    |Event Number:   37152       |
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| FACILITY: LIMERICK                 REGION:  1  |NOTIFICATION DATE: 07/08/2000|
|    UNIT:  [] [2] []                 STATE:  PA |NOTIFICATION TIME: 08:33[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        07/08/2000|
+------------------------------------------------+EVENT TIME:        04:40[EDT]|
| NRC NOTIFIED BY:  GREG SOSSON                  |LAST UPDATE DATE:  07/24/2000|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |STEVEN DENNIS        R1      |
|10 CFR SECTION:                                 |                             |
|AUNA 50.72(b)(1)(ii)(A)  UNANALYZED COND OP     |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |52       Power Operation  |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| UNANALYZED CONDITION                                                         |
|                                                                              |
| At 04:40 the Unit 2 #4 Main Turbine control valve closed.  No testing or     |
| maintenance was in progress at the time of the valve closure.  Plant         |
| Operating procedures specify that the MCPR thermal limit is not analyzed for |
| this condition. The appropriate technical specification action is being      |
| entered to reduce power to below 25% power within 6 hours.  Reactor power is |
| currently 52% and being reduced.                                             |
|                                                                              |
| At 07:47 it was determined that an unanalyzed condition exists on Unit 2     |
| that has the potential to compromise plant safety based on the above         |
| condition.                                                                   |
|                                                                              |
| The cause of the control valve failure is not determined at this time.  At   |
| the time of the control valve closure, reactor power and pressure remained   |
| stable with one main turbine bypass valve opening approximately 40%. Power   |
| was immediately reduced to 95% in accordance with plant procedures.  The     |
| bypass valve closed.                                                         |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
|                                                                              |
| * * * RETRACTED AT 1341 EDT ON 7/24/00 BY STAN GAMBLE TO FANGIE JONES * * *  |
|                                                                              |
| "This is a retraction of a notification made on 07/08/00 at 08:33 hours,     |
| (event #37152). This event was reported as an unanalyzed condition under     |
| requirement 10CFR50.72(b)(1)(ii)(A).                                         |
|                                                                              |
| "Unit 2 Main Turbine control valve (TCV) failed closed at 100% power. The    |
| Technical Specification MCPR thermal limit is not analyzed for extended      |
| operation with one TCV in the closed position. Power was reduced to less     |
| than 25% within the TS AOT.                                                  |
|                                                                              |
| "The basis for this retraction is that the effect of the closed TCV has been |
| evaluated by PECO Energy engineering with the following results. The TCV     |
| slow closure resulted in a mild pressure transient that did not challenge    |
| the MCPR Safety Limit. This phase was bounded by the limiting MCPR event of  |
| load reject without bypass.                                                  |
|                                                                              |
| "The load drop to 25% power was uncomplicated and completed within four (4)  |
| hours and twenty (20) minutes. The leading MFLCPR value for this period was  |
| 0.961. This complied with the MCPR TS AOT of six (6) hours. This period was  |
| of short duration and bounded by the existing Design Bases Accidents.        |
|                                                                              |
| "The MCPR TS LCO is not applicable to operation at less than 25% power. This |
| period of operation is also considered analyzed.                             |
|                                                                              |
| "Since all phases of the transient and reduced power operation are           |
| explicitly analyzed or bounded by existing analysis, this event is           |
| considered analyzed. In addition, this event did not significantly           |
| compromise plant safety.                                                     |
| An unanalyzed condition that significantly compromises plant safety did not  |
| occur. Therefore, this event is not reportable per the guidance of           |
| NUREG-1022, Rev 1."                                                          |
|                                                                              |
| The licensee notified the NRC Resident Inspector.  The NRC Operations        |
| Officer notified the R1DO (Mohamed Shanbaky)                                 |
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!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED  !!!!!!!
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|Power Reactor                                    |Event Number:   37163       |
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| FACILITY: LASALLE                  REGION:  3  |NOTIFICATION DATE: 07/11/2000|
|    UNIT:  [1] [] []                 STATE:  IL |NOTIFICATION TIME: 21:40[EDT]|
|   RXTYPE: [1] GE-5,[2] GE-5                    |EVENT DATE:        07/11/2000|
+------------------------------------------------+EVENT TIME:        19:50[CDT]|
| NRC NOTIFIED BY:  RUSSELL BENNETT              |LAST UPDATE DATE:  07/24/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |BRUCE JORGENSEN      R3      |
|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          Y       100      Power Operation  |100      Power Operation  |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| UNIT OUTSIDE DESIGN BASIS DUE TO 10 CFR PART 50, APPENDIX R ISSUE            |
|                                                                              |
| "At approximately 1610 on 7/11/2000, it was identified by plant walkdown     |
| that in electrical switchgear Bus 142Y (1AP06B) cubicle 4 (for the Unit 1 B  |
| Residual Heat Removal pump) that an unsealed borehole of approximately three |
| (3) inches in diameter existed. This borehole is located in the floor        |
| separating the Unit 1 Division 2 Switchgear room from the Unit 1 Division 1  |
| switchgear room. The borehole is located in a three (3) hour rated fire      |
| barrier that is required by Administrative Technical Requirement 3/4.7.6     |
| (Fire Rated Assemblies). This has been considered an event that is outside   |
| the design basis due to required design basis protective features for safe   |
| shutdown trains as described in 10 CFR 50, Appendix R and Final Safety       |
| Analysis Report [being] lacking. Compensatory measures (fire watches) have   |
| been established per Administrative Technical Specifications and plans for   |
| repairs are in progress."                                                    |
|                                                                              |
| The NRC resident inspector has been notified of this event by the licensee.  |
|                                                                              |
| * * * UPDATE 1155 7/12/00 FROM ROCKY HASTY TAKEN BY BOB STRANSKY * * *       |
|                                                                              |
| "Additionally, on 7/7/2000, another unsealed borehole of 2.75 inches in      |
| diameter was identified in non-safety Switchgear bus 152 (1AP02B) cubicle 4. |
| Both boreholes are located in the floor separating the Unit 1 Division 1     |
| switchgear room from the Unit 1 Division 2 Switchgear room. Both boreholes   |
| are in a three (3) hour rated fire barrier that is required by               |
| Administrative Technical Requirement 3/4.7.6 (Fire Rated Assemblies). This   |
| has been considered an event that is outside the design basis due to         |
| required design basis protective features for safe shutdown trains as        |
| described in 10 CFR 50, Appendix R and Final Safety Analysis Report (FSAR)   |
| [being] lacking."                                                            |
|                                                                              |
| The NRC resident inspector has been informed of this update. Notified R3DO   |
| (Jorgensen).                                                                 |
|                                                                              |
| * * * RETRACTED ON 7/24/00 AT 1617 EDT BY JOHN REIS  TO FANGIE JONES * * *   |
|                                                                              |
| "...The preliminary evaluation could not determine whether or not the two    |
| unsealed penetrations in the three-hour fire barrier between the Unit 1      |
| Division 1 switchgear room and the Unit 1 Division 2 switchgear room would   |
| cause failure of both electrical divisions during a fire in either division  |
| switchgear room. Should such a fire cause division failure in both           |
| switchgear rooms, the station would be outside the safe shutdown analysis    |
| performed to meet 10 CFR 50, Appendix R as described in the LaSalle County   |
| Station Updated Final Safety Analysis Report. The NRC event number was       |
| 37163.                                                                       |
|                                                                              |
| "The investigation has determined that LaSalle County Station Unit 1 was     |
| operating within the plant design basis while operating Unit 1 with two      |
| unsealed openings in the fire barrier assembly separating the Division 1 and |
| Division 2 Switchgear Rooms.                                                 |
|                                                                              |
| "A fire evaluation has been performed that concludes that Unit 1 could have  |
| been safely shutdown following a design basis fire in either Switchgear Room |
| based on the fire loading in the rooms, the design of the switchgear, the    |
| type of electrical cables, fire detection and the fire brigade. Therefore,   |
| LaSalle County Station was operating within plant design basis when          |
| operating Unit 1 with the condition described above. Extent of condition     |
| evaluation/walkdowns have not identified any 10 CFR 50 Appendix R            |
| deficiencies. Unit 2 remains unaffected.                                     |
|                                                                              |
| "Therefore it has been determined that this event is not reportable to the   |
| NRC, and this event notification is being                                    |
| retracted."                                                                  |
|                                                                              |
| The licensee notified the NRC Resident Inspector.  The NRC Operations        |
| Officer notified the R3DO (Michael Parker).                                  |
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|Power Reactor                                    |Event Number:   37184       |
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| FACILITY: BROWNS FERRY             REGION:  2  |NOTIFICATION DATE: 07/24/2000|
|    UNIT:  [] [2] [3]                STATE:  AL |NOTIFICATION TIME: 15:20[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4,[3] GE-4           |EVENT DATE:        07/24/2000|
+------------------------------------------------+EVENT TIME:        13:22[CDT]|
| NRC NOTIFIED BY:  RAYMOND SWAFFORD             |LAST UPDATE DATE:  07/24/2000|
|  HQ OPS OFFICER:  FANGIE JONES                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |BRIAN BONSER         R2      |
|10 CFR SECTION:                                 |                             |
|ACNC 50.72(b)(1)(ii)(C)  COND OUTSIDE EOPS      |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|3     N          Y       100      Power Operation  |100      Power Operation  |
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                                   EVENT TEXT                                   
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| APPENDIX R REVIEW DISCOVERED A CONDITION OF NONCOMPLIANCE WITH THE SAFE      |
| SHUTDOWN CAPABILITIES OF THE RHR SYSTEM                                      |
|                                                                              |
| "On 7/24/2000 at approximately 1322 CST, a review of the Appendix R Safe     |
| Shutdown Program revealed that a condition of noncompliance with 10CFR50 App |
| R Criteria III L.2 existed for Units 2 and 3, for availability of the        |
| minimum flow valves for the RHR Pumps. The BFN Appendix R program assumes    |
| the Residual Heat Removal (RHR) minimum flow valves are open following the   |
| initiation of RHR and remain open until vessel injection is initiated.       |
| Contrary to this assumption, the cables to the valves have not been verified |
| to be protected from the effects of a fire. Consequently the valves could    |
| spuriously close and dead head the pump for an extended period of time.      |
|                                                                              |
| "This condition is being reported lAW 10 CFR 50.72.b.1.ii(c) as a 1 hour     |
| report as '... a condition not covered by the plant's operating and          |
| emergency procedures.''                                                      |
|                                                                              |
| The licensee is conducting an investigation and posting fire watches in the  |
| mean time.                                                                   |
|                                                                              |
| The licensee notified the NRC Resident Inspector.                            |
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