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 THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!!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 |
| | |
| | |
+------------------------------------------------------------------------------+
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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Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021