ENS 45747: Difference between revisions

v t e ENS Event
19:25 Mar 5, 2010
Title	Unanalyzed Condition - Steam Supply Valve Credited as Closed in Fsar Analysis Is Normally Open During Operations
Event Description	Valve FBV0147, Boric Acid Batch Tank Auxiliary Steam Supply Isolation Valve, is credited with being closed in the Callaway FSAR. This eliminated the need to analyze lines FB-081-HBD and FB-082-HBD for high energy line breaks (HELB). However, FBV0147 was found to be kept normally open to allow steam service for the boric acid batching tank. This is contrary to the normal position assumed in the FSAR and HELB analyses. With valve FBV0147 open, the lines must considered high energy lines. The lines are in the auxiliary building and they traverse rooms containing several components including the flow transmitters for Residual Heat Removal (RHR) to train `A' accumulator injection supply header, RHR train `A' and 'B' SIS hot leg recirculation supply header, and several safety related auxiliary feedwater components. These instruments are used to provide indications during post-accident conditions. This configuration is therefore outside of current HELB analysis and potentially represents a condition that significantly degrades plant safety. The condition was identified to Operations at 0740. Valve FBV0147 was closed at 0810. At 1325 CST, the issue was determined to be reportable. The NRC Resident Inspector has been notified. * * RETRACTION AT 1557 EDT ON 5/3/10 FROM HURT TO HUFFMAN * * * On 03/05/2010, EN #45747 provided notification that valve FBV0147 was found to be kept normally open to allow steam service for the boric acid hatching tank. This configuration was not consistent with the normal position assumed in the FSAR and HELB analyses. An engineering evaluation was subsequently performed for the auxiliary steam inlet and outlet piping for the boric acid batching tank. This valuation identified four postulated break locations which have all been analyzed. The analyses determined that all safety-related components in the affected rooms would be able to perform their safety functions in the event of a line break. Pipe whip, jet impingement, compartment temperature and over pressurization, flooding, and internal missiles resulting from a postulated line break would not prevent any safety-related equipment from performing its design function. As supported by this evaluation, this condition does not meet the criteria for an unanalyzed condition that significantly degrades plant safety as stated in 10 CFR 50.72(b)(3)(ii)(B). Therefore, the notification made on 03/05/2010 is hereby retracted. The NRC Resident Inspector will be notified. R4DO (Farnholtz) notified.

ENS 45747 +/- *RETRACTED*
Where
Callaway Missouri (NRC Region 4)
Reporting

10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition
Time - Person (Reporting Time:+-2.88 h-0.12 days <br />-0.0171 weeks <br />-0.00395 months <br />)
Opened:	David Hurt 16:32 Mar 5, 2010
NRC Officer:	Howie Crouch
Last Updated:	May 3, 2010
45747 - 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 45747\u003C/a\u003E - \u003Ca href=\"/Callaway\" title=\"Callaway\"\u003ECallaway\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnanalyzed Condition - Steam Supply Valve Credited as Closed in Fsar Analysis Is Normally Open During Operations\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 45747 - Callaway\n","link":"","lat":38.76076111111111,"lon":-91.78175833333333,"icon":"/w/images/0/06/Ameren_icon.png"}],"imageoverlays":null}
v • d • e

v t e Emergency Notification System
Callaway with 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition
WEEKMONTHYEAR2020-07-30T13:15:00 [Table view]
[ENS list for Callaway]

@@ Line 17: / Line 17: @@
 | event date = 03/05/2010 13:25 CST
 | last update date = 05/03/2010
-| title = Unanalyzed Condition - Steam Supply Valve Credited As Closed In Fsar Analysis Is Normally Open During Operations
+| title = Unanalyzed Condition - Steam Supply Valve Credited as Closed in Fsar Analysis Is Normally Open During Operations
 | event text = Valve FBV0147, Boric Acid Batch Tank Auxiliary Steam Supply Isolation Valve, is credited with being closed in the Callaway FSAR. This eliminated the need to analyze lines FB-081-HBD and FB-082-HBD for high energy line breaks (HELB). However, FBV0147 was found to be kept normally open to allow steam service for the boric acid batching tank. This is contrary to the normal position assumed in the FSAR and HELB analyses.
 With valve FBV0147 open, the lines must considered high energy lines. The lines are in the auxiliary building and they traverse rooms containing several components including the flow transmitters for Residual Heat Removal (RHR) to train `A' accumulator injection supply header, RHR train `A' and 'B' SIS hot leg recirculation supply header, and several safety related auxiliary feedwater components. These instruments are used to provide indications during post-accident conditions. This configuration is therefore outside of current HELB analysis and potentially represents a condition that significantly degrades plant safety.

v t e Unit 1
W-4-LP
Reactor critical	Critical
Scram	No
Before	Power Operation (100 %)
After	Power Operation (100 %)

ENS 45747: Difference between revisions

Latest revision as of 22:09, 1 March 2018

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ENS 45747: Difference between revisions

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