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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Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021