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Event Notification Report for March 21, 2001

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           03/20/2001 - 03/21/2001

                              ** EVENT NUMBERS **

37850  37852  

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|Power Reactor                                    |Event Number:   37850       |
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| FACILITY: VERMONT YANKEE           REGION:  1  |NOTIFICATION DATE: 03/19/2001|
|    UNIT:  [1] [] []                 STATE:  VT |NOTIFICATION TIME: 14:22[EST]|
|   RXTYPE: [1] GE-4                             |EVENT DATE:        03/19/2001|
+------------------------------------------------+EVENT TIME:        12:32[EST]|
| NRC NOTIFIED BY:  JAMES KRITZER                |LAST UPDATE DATE:  03/20/2001|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |KENNETH JENISON      R1      |
|10 CFR SECTION:                                 |                             |
|*RPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|*ESF 50.72(b)(3)(iv)(A)  VALID SPECIF SYS ACTUAT|                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     A/R        Y       100      Power Operation  |0        Hot Shutdown     |
|                                                   |                          |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| REACTOR SCRAM                                                                |
|                                                                              |
| On 3/19/2001, at 1232 a reactor scram signal was received, all rods inserted |
| after the scram.  Reactor Pressure Vessel  (RPV) water level dropped below   |
| 127" (normal water level is about 160") which actuated primary containment   |
| isolation signals for groups 2, 3 and 5.  RPV water level is being           |
| controlled by feedwater and RPV pressure control is via turbine bypass       |
| valves.  The plant is stable.  The cause of the reactor scram is under       |
| investigation.                                                               |
|                                                                              |
| The licensee notified the NRC resident inspector and will notify the state   |
| authorities.  A press release may be issued.                                 |
|                                                                              |
| * * * UPDATE AT 1257 ON 3/20/01, BY KRITZER RECEIVED BY WEAVER * * *         |
|                                                                              |
| "The cause of the 3/19/2001 scram has been determined to be faulty auxiliary |
| contacts in Reactor Protection System (RPS) relay 5A-K13D.  The auxiliary    |
| contacts failed to open during reset of a  scram condition on the RPS "B"   |
| auto scram channel inserted during surveillance testing earlier in the       |
| shift.  There were no means available to the operators to detect this        |
| failure.  Subsequent surveillance testing of RPS "A" inserted a  scram on   |
| RPS "A" auto scram channel which resulted in the energization of backup      |
| scram valve 3-140B.  The energization of the backup scram valve vented the   |
| scram air header which led to the full reactor scram.   Repairs have been    |
| completed and the plant is preparing for restart."                           |
|                                                                              |
| The licensee notified the NRC resident inspector.  The Operations Center     |
| notified R1DO (Jenison).                                                     |
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|Power Reactor                                    |Event Number:   37852       |
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| FACILITY: SUSQUEHANNA              REGION:  1  |NOTIFICATION DATE: 03/20/2001|
|    UNIT:  [] [2] []                 STATE:  PA |NOTIFICATION TIME: 14:51[EST]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        03/20/2001|
+------------------------------------------------+EVENT TIME:        08:00[EST]|
| NRC NOTIFIED BY:  GORDON ROBINSON              |LAST UPDATE DATE:  03/20/2001|
|  HQ OPS OFFICER:  DOUG WEAVER                  +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |KENNETH JENISON      R1      |
|10 CFR SECTION:                                 |                             |
|*DEG 50.72(b)(3)(ii)(A)  DEGRAD COND DURING OP  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          N       0        Refueling        |0        Refueling        |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| DEGRADED WHILE SHUTDOWN                                                      |
|                                                                              |
| With Unit 2 in Mode 5 on the 11th day of its 10th Refuel and Inspection      |
| Outage, it has been determined that the CRD Seismic Island leakage rate      |
| criterion of 508 mI/hr has been exceeded.   During performance of the        |
| Hydraulic Leak Test of CRD Seismic Island Check Valves, SE-259-150, a        |
| leakage rate of 20 ccm was recorded for Test 1 (valve # 246027) and a        |
| leakage rate of 14.3 ccm was recorded for Test 2 (valve 246028).  With this  |
| leak rate, the 'Minimum Path' CRD Seismic Island Check Valve leak rate is    |
| 858 mI/hr.  This leak rate exceeds the criteria of 508 mI/hr specified in    |
| FSAR Table 6.2-15, Evaluation of Secondary Containment Bypass Leakage        |
| Pathways.                                                                    |
|                                                                              |
| This condition constitutes a degraded plant condition and requires an 8 hour |
| ENS Notification in accordance with 10CFR50.72(b)(3)(ii)(A).                 |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
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