ENS 44562
ENS Event | |
---|---|
09:45 Oct 11, 2008 | |
Title | Unanalyzed Condition Due to Vendor Calculation Error |
Event Description | Turkey Point received notification of an error in a vendor calculation methodology regarding the containment building heat transfer. This calculation is used to support containment temperature and pressure as well as heat input to the Component Cooling Water system under design basis accident conditions.
While validating a new analysis model, it was discovered that the Turkey Point containment steel liner was not included in the analysis of record. This is a non-conservative error in that less heat would be expected to be transferred to the external environment with the presence of the liner. The initial evaluation of the error indicates that at the maximum allowable Ultimate Heat Sink (Intake) temperature, Containment pressure, long-term Containment temperature and Component Cooling Water return temperature could exceed licensing basis limits during a design basis accident. Preliminary analysis indicates that under current Ultimate Heat Sink conditions, operability requirements are met. The licensee notified the NRC Resident Inspector.
The purpose of this update is to retract EN#44562 submitted to the NRC Operations Center on October 11, 2008. FPL has performed a detailed evaluation of the impact of errors identified by Westinghouse in the Loss of Coolant Accident (LOCA) containment analysis of record on the operation of Turkey Point Units 3 and 4. The evaluation took into consideration actual ultimate heat sink (intake cooling water - ICW) temperatures, and removed conservatisms used in the LOCA containment integrity analysis and Component Cooling Water (CCW) system analysis. The evaluation confirmed that the Units 3 and 4 containment structures were capable of performing the safety function required by the Technical Specifications. Additionally, after removal of conservatisms in conjunction with a minimum CCW heat exchanger heat removal capability consistent with an ICW temperature of 95 degrees F, and an assumed CCW heat exchanger tube resistance, the long term containment temperature and CCW return temperature would not have exceeded licensing basis limits during a design basis accident. The evaluation determined that Turkey Point Units 3 and 4 were not in an unanalyzed condition that significantly degraded plant safety as a result of the containment integrity analysis error and this event is not reportable under 10CFR50.72(b)(3)(ii)(B) criteria. Therefore, EN#44562 is retracted. The evaluation described above is documented in the Corrective Action Program in report 2008-31338 . The licensee will notify the NRC Resident Inspector. Notified R2DO(Nease). |
Where | |
---|---|
Turkey Point Florida (NRC Region 2) | |
Reporting | |
10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
Time - Person (Reporting Time:+0.63 h0.0263 days <br />0.00375 weeks <br />8.62974e-4 months <br />) | |
Opened: | Dewey Barrow 10:23 Oct 11, 2008 |
NRC Officer: | Jeff Rotton |
Last Updated: | Mar 16, 2009 |
44562 - 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 44562\u003C/a\u003E - \u003Ca href=\"/Turkey_Point\" title=\"Turkey Point\"\u003ETurkey Point\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnanalyzed Condition Due to Vendor Calculation Error\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 44562 - Turkey Point\n","link":"","lat":25.435330555555556,"lon":-80.33125833333334,"icon":"/w/images/9/9b/NextEra_Energy_icon.png"}],"imageoverlays":null} | |
Unit 3 | |
---|---|
Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |
Unit 4 | |
---|---|
Reactor critical | Not Critical |
Scram | No |
Before | Hot Standby (0 %) |
After | Hot Standby (0 %) |
WEEKMONTHYEARENS 508072015-02-10T22:50:00010 February 2015 22:50:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition High Head Safety Injection Inoperable Due to Missing Piping Support ENS 445622008-10-11T09:45:00011 October 2008 09:45:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Vendor Calculation Error ENS 411022004-10-07T18:00:0007 October 2004 18:00:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition, 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material Single Point Vulnerability in Emergency Containment Filter Dousing System 2015-02-10T22:50:00 | |