Event Notification Report for February 23, 1999
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
02/22/1999 - 02/23/1999
** EVENT NUMBERS **
35390 35392 35393
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|Power Reactor |Event Number: 35390 |
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| FACILITY: SEABROOK REGION: 1 |NOTIFICATION DATE: 02/21/1999|
| UNIT: [1] [] [] STATE: NH |NOTIFICATION TIME: 11:28[EST]|
| RXTYPE: [1] W-4-LP |EVENT DATE: 02/20/1999|
+------------------------------------------------+EVENT TIME: 21:00[EST]|
| NRC NOTIFIED BY: STEVE MORRISSEY |LAST UPDATE DATE: 02/22/1999|
| HQ OPS OFFICER: JOHN MacKINNON +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |JIM TRAPP R1 |
|10 CFR SECTION: | |
|NLTR LICENSEE 24 HR REPORT | |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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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| ELEVEN DEAD SEA DUCKS FOUND IN CIRCULATING WATER SCREEN WASH DEBRIS |
| |
| Eleven dead sea ducks were observed in Seabrook station's circulating water |
| screen wash debris on February 20, 1999 at approximately 2100 hours. It is |
| not known at this time whether the ducks were alive or dead upon entering |
| the offshore intake structure. Sea ducks are diving birds which feed |
| underwater. This is a 24 hour notification in accordance with section 4.1 |
| of the environmental protection plan, appendix B of the operating license. |
| |
| The NRC resident inspector was notified of this event report by the |
| licensee. |
| |
| * * * UPDATE AT 1407 EST ON 2/22/99 BY STEVE MORRISSEY TO FANGIE JONES * * |
| * |
| |
| Two additional dead sea ducks were observed in Seabrook station's |
| circulating water screen wash debris on February 21, 1999 at approximately |
| 2245 hours. The licensee believes these additional dead sea ducks are part |
| of the original group and were not picked up on the screen wash of the night |
| of February 20, 1999. |
| |
| The licensee notified the NRC Resident Inspector. The Operations Officer |
| notified the R1DO (Richard Barkley). |
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|Power Reactor |Event Number: 35392 |
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| FACILITY: GINNA REGION: 1 |NOTIFICATION DATE: 02/22/1999|
| UNIT: [1] [] [] STATE: NY |NOTIFICATION TIME: 16:27[EST]|
| RXTYPE: [1] W-2-LP |EVENT DATE: 02/22/1999|
+------------------------------------------------+EVENT TIME: 15:40[EST]|
| NRC NOTIFIED BY: ROY GILLOW |LAST UPDATE DATE: 02/22/1999|
| HQ OPS OFFICER: FANGIE JONES +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |RICHARD BARKLEY R1 |
|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 75 Power Operation |75 Power Operation |
| | |
| | |
+------------------------------------------------------------------------------+
EVENT TEXT
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| DISCOVERY OF MODELING ERRORS IN THE MAIN STEAM LINE BREAK ANALYSIS |
| |
| The following text is a portion of a facsimile received from the licensee: |
| |
| "Ginna Station was notified by its NSSS vendor, Westinghouse Electric |
| Company, of two modeling errors in the analysis for a main steam line break |
| (MSLB) with an assumed single failure of a feed water control valve. The |
| first error was not taking into account the full amount of energy released |
| to containment by the flashing of high temperature feed water downstream of |
| the motor operated isolation valves after feed water flow is isolated. The |
| second error was a mistake in the assumed time of feed water isolation. |
| Isolation should have occurred at 85 seconds but incorrectly occurred at 15 |
| seconds. |
| |
| "Preliminary analyses show that in the past, under the postulated conditions |
| of a MSLB coincident with a feed water regulating valve failure, the |
| containment pressure design limit may have been exceeded and that Ginna |
| Station may have been in a condition outside the design basis of the plant. |
| This condition is also being evaluated for the criteria of l0CFR2l. |
| However, a recently performed analysis for the current operating cycle using |
| more realistic modeling assumptions, accounting for cycle specific shutdown |
| margin values and crediting current heat sink temperatures showed that |
| acceptable results (less than 60 psig) were obtained. Thus there is no |
| concern for continued plant operation through the end of the current cycle |
| (March 1, 1999) based on these results." |
| |
| Further analyses will be performed prior to the plant restarting after the |
| next refueling. |
| |
| The licensee notified the NRC Resident Inspector. |
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|Power Reactor |Event Number: 35393 |
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| FACILITY: DUANE ARNOLD REGION: 3 |NOTIFICATION DATE: 02/22/1999|
| UNIT: [1] [] [] STATE: IA |NOTIFICATION TIME: 22:12[EST]|
| RXTYPE: [1] GE-4 |EVENT DATE: 02/22/1999|
+------------------------------------------------+EVENT TIME: 20:45[CST]|
| NRC NOTIFIED BY: KEVIN STEIMER |LAST UPDATE DATE: 02/22/1999|
| HQ OPS OFFICER: FANGIE JONES +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: N/A |BRUCE JORGENSEN R3 |
|10 CFR SECTION: | |
|AINC 50.72(b)(2)(iii)(C) POT UNCNTRL RAD REL | |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|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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| BOTH STANDBY GAS TREATMENT SYSTEMS MOMENTARILY INOPERABLE |
| |
| The following text is a portion of a facsimile received from the licensee: |
| |
| "The 'B' Standby Gas Treatment (SBGT) subsystem was undergoing its 10-hour |
| monthly surveillance testing when it was discovered that the flow indicating |
| controller for the 'A' train was not properly displaying flow. The 'A' SBGT |
| subsystem was declared inoperable at 1113 on 2/22/99 while monthly |
| surveillance testing continued on the 'B' SBGT subsystem. Repairs were |
| completed on the 'A' flow indicating controller coincident with the ongoing |
| surveillance test on the 'B' SBGT subsystem. |
| |
| "In accordance with the monthly surveillance for shutting down a 'B' SBGT |
| subsystem, its mode selector switch was momentarily placed in the manual |
| position at 2045 hours for approximately 15 seconds, which in effect |
| disabled 'B' SBGT from automatically starting and it was therefore declared |
| inoperable. For those 15 seconds, both SBGT subsystems were considered |
| inoperable which is a condition that could prevent the fulfillment of the |
| safety function of SBGT system to control the release of radioactive |
| material. This is considered a 4-hour reportable event per |
| 50.72(b)(2)(iii)(C). |
| |
| "The 'B' SBGT subsystem was restored to operable status once the mode |
| selector switch was returned to the auto position. Surveillance testing is |
| currently in progress on the 'A' SBGT subsystem to demonstrate operability |
| for the repairs made to its flow indicating controller." |
| |
| The licensee notified the NRC Resident Inspector. |
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