ENS 45073
ENS Event | |
|---|---|
22:01 May 16, 2009 | |
| Title | Failure of High Pressure Coolant Injection Steam Supply Valve to Close During Test |
| Event Description | At 1801 on 5/16/2009, the HPCI turbine steam supply valve (HV255F001) failed to close during shutdown of the system following performance of its quarterly flow surveillance. The auxiliary oil pump was de-energized to prevent an inadvertent start of HPCI and the HPCI system was declared inoperable.
LCO 3.5.1 for the HPCI system being inoperable was entered at 1720 on 5/16/2009 at the start of the HPCI surveillance. An investigation is in progress to determine the nature of the problem. This is being reported as an event or condition that could have prevented fulfillment of a safety function required to mitigate the consequences of an accident in accordance with 10 CFR 50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.
On May 16, 2009, the HPCI system was declared inoperable at 1720 hours0.0199 days <br />0.478 hours <br />0.00284 weeks <br />6.5446e-4 months <br /> and LCO 3.5.1 was entered to support the planned quarterly HPCI flow surveillance test. During the surveillance test, at 1801 hours0.0208 days <br />0.5 hours <br />0.00298 weeks <br />6.852805e-4 months <br />, the HPCI turbine steam supply valve (HV255F001) failed to close during shutdown of the system. It was also identified that neither the open nor closed indication lamp in the control room were lit. Troubleshooting was performed by cycling the valve's breaker in an attempt to restore power to the HPCI steam supply valve. No movement of the valve was observed. Because the position of the HPCI steam supply valve was unknown, Operations secured HPCI by opening the auxiliary oil pump breaker for the purpose of conducting additional troubleshooting (maintenance) of the failure of the HV255F001 valve to close. On 5/16/09 at 2004 hours0.0232 days <br />0.557 hours <br />0.00331 weeks <br />7.62522e-4 months <br /> EDT, Susquehanna made an 8-hour ENS notification (45703) to the NRC, due to HPCI being declared inoperable when HV255F001 failed to close during performance of the quarterly surveillance. Subsequent investigation concluded that the HPCI turbine steam supply valve (HV255F001) did close as expected, but did not indicate closed due to a loss of position indication. It was determined that the closed indicating lamp had burned out. Upon replacement of the lamp, the valve was successfully stroked open and closed and HPCI was declared operable at 0800 EDT 5/17/2009. Because a condition did not exist at the time of discovery that could have prevented the fulfillment of a safety function in accordance with 10 CFR 50.72(b)(3)(v)(D), EN #45073 is hereby being retracted. It should be noted that the subsequent action to disable HPCI by opening the auxiliary oil pump break does not preclude retraction of the ENS notification. This action did not create a new reportable condition since HPCI was already inoperable for planned surveillance testing. This action was taken as part of troubleshooting activities (maintenance) on the HV255F001 valve and to prevent an inadvertent start of HPCI. The NRC Resident has been notified. Notified R1DO (Gray) |
| Where | |
|---|---|
Susquehanna  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+-1.95 h-0.0813 days <br />-0.0116 weeks <br />-0.00267 months <br />) | |
| Opened: | Martin Lichtner 20:04 May 16, 2009 |
| NRC Officer: | Pete Snyder |
| Last Updated: | Jul 16, 2009 |
| 45073 - NRC Website
Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 45073\u003C/a\u003E - \u003Ca href=\"/Susquehanna\" title=\"Susquehanna\"\u003ESusquehanna\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EFailure of High Pressure Coolant Injection Steam Supply Valve to Close During Test\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 45073 - Susquehanna\n","link":"","lat":41.09256666666667,"lon":-76.14176944444445,"icon":"/w/images/c/c7/Talen_Energy_icon.png"}],"imageoverlays":null} | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (13 %) |
| After | Power Operation (13 %) |