Event Notification Report for November 28, 2000
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
11/27/2000 - 11/28/2000
** EVENT NUMBERS **
37469
!!!!!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!!!
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|Power Reactor |Event Number: 37469 |
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| FACILITY: SURRY REGION: 2 |NOTIFICATION DATE: 10/28/2000|
| UNIT: [1] [2] [] STATE: VA |NOTIFICATION TIME: 17:40[EDT]|
| RXTYPE: [1] W-3-LP,[2] W-3-LP |EVENT DATE: 10/28/2000|
+------------------------------------------------+EVENT TIME: 15:11[EDT]|
| NRC NOTIFIED BY: HARROW |LAST UPDATE DATE: 11/27/2000|
| HQ OPS OFFICER: JOHN MacKINNON +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |ANNE BOLAND 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 Y 100 Power Operation |100 Power Operation |
|2 N N 0 Hot Shutdown |0 Hot Shutdown |
| | |
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EVENT TEXT
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| RWST CROSS-TIE VALVES UNEXPECTEDLY OPENED DURING PLANNED MAINTENANCE |
| |
| At 1511 hours, with Unit 2 in Intermediate Shutdown (ISD), approximately 375 |
| degrees F, Unit 1 and Unit 2 RWST Cross-tie-valves opened when the High |
| Steam Flow SI signal was unblocked for planned maintenance. By design, the |
| Header to Line SI signal which opens these valves is unblocked when High |
| Steam Flow is unblocked. At the time of the unblock, a header to line |
| condition existed on Unit 2 due to plant conditions. This design was newly |
| implemented during the current Unit 2 refueling outage and procedures did |
| not provide adequate steps to prevent the valves from opening. A Header to |
| Line SI signal was not received as it was properly defeated in accordance |
| with station procedures. The cross-tie valves were manually closed when the |
| condition was identified as not required. |
| |
| Unit 1 is currently at 100% power. Unit 2 is in Intermediate Shutdown with |
| RCS heatup and pressurization in progress. |
| |
| The NRC Resident Inspector was notified of this event by the licensee. |
| |
| * * * UPDATE 1725EST ON 11/27/00 FROM ALLEN HARROW TO S. SANDIN * * * |
| |
| The licensee is retracting this report based on the following: |
| |
| "At 1740 hours on 10/28/00, Surry Power Station made a 4 hour Non-Emergency |
| Notification in accordance with 10CFR50.72(b)(2)(ii) due to the opening of |
| the RWST Cross-tie valves when the High Steam Flow SI signal was unblocked |
| for planned maintenance (Event Number 37469). |
| |
| "Based on further review of the event reported on October 28, 2000 it has |
| been determined that the conditions did not meet the criteria of 10CFR50.72 |
| as clarified in NUREG 1022, Rev 1. The NUREG states: |
| |
| 'Usually, the staff would not consider this to include single component |
| actuations because single components of complex systems, by themselves, |
| usually do not mitigate the consequences of significant events. However, in |
| some cases a component would be sufficient to mitigate the event (i.e. |
| perform the ESF function) and its actuation would, therefore, be reportable. |
| This position is consistent with the statement that the reporting |
| requirement is based on the premise that ESFs are provided to mitigate the |
| consequence of a significant event. |
| |
| 'Single trains do mitigate the consequences, and, thus, train level |
| actuations are reportable.' |
| |
| "Specifically, the initial assessment considered the event as an ESF |
| actuation and therefore reportable under criterion 10CFR50.72(b)(2)(ii). The |
| nature of this event does not constitute a train actuation. The only signal |
| affected was that going to the RWST Cross-tie valves. This occurred because |
| the block signal was unblocked due to placing the RCS narrow range |
| temperature loops in trip while performing the RTD cross calibrations while |
| heating up Unit 2 following a refueling outage. The details of this event |
| are consistent with the discussion and examples of NUREG 1022 that would not |
| be reported. |
| |
| "This notification is being made to retract the report made on 10/28/00 |
| based on the above discussion." |
| |
| The licensee informed the NRC resident inspector. Notified R2DO(Rodgers). |
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