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Event Notification Report for June 13, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           06/12/2000 - 06/13/2000

                              ** EVENT NUMBERS **

37077  

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|Power Reactor                                    |Event Number:   37077       |
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| FACILITY: KEWAUNEE                 REGION:  3  |NOTIFICATION DATE: 06/12/2000|
|    UNIT:  [1] [] []                 STATE:  WI |NOTIFICATION TIME: 11:50[EDT]|
|   RXTYPE: [1] W-2-LP                           |EVENT DATE:        06/12/2000|
+------------------------------------------------+EVENT TIME:        09:15[CDT]|
| NRC NOTIFIED BY:  GARY HARRINGTON              |LAST UPDATE DATE:  06/12/2000|
|  HQ OPS OFFICER:  BOB STRANSKY                 +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DAVID HILLS          R3      |
|10 CFR SECTION:                                 |                             |
|ADAS 50.72(b)(2)(i)      DEG/UNANALYZED COND    |                             |
|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       71       Power Operation  |71       Power Operation  |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| INADEQUATE SERVICE WATER SYSTEM FLOW TO EDGs (HISTORICAL REPORT)             |
|                                                                              |
| "On June 2, 2000, Kewaunee completed a scheduled refueling outage. During    |
| the outage, comprehensive flow data was measured on the plant's service      |
| water system. Subsequent analysis of the flow data revealed that for less    |
| than one hour on August 8, 1991, both of the redundant diesel generators     |
| could have had cooling water flow below design basis post-accident           |
| requirements. The cause of the condition is a combination of elevated        |
| cooling water temperatures, conservative calculation assumptions using       |
| recent data, and a previously unidentified design problem that results in    |
| reduced flow through the diesel coolers. The design problem occurs due to    |
| system backpressure caused by the diesels' cooling water discharges being    |
| connected to a common header. During the outage, the diesel generator heat   |
| exchangers were replaced for reasons unrelated to this report. The new heat  |
| exchangers' increased capacity precludes recurrence."                        |
|                                                                              |
| The NRC resident inspector has been informed of this event by the licensee.  |
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