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Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Topic From Panel EVAL DETAILS TIMElOO 1.0 ISSUE IDENTIFICATION: Last Updated By : Last Updated Date: Text Status Page: 1 BYRVB 07/01/2009 UNLOCKED Title: OP EVAL 07-006, AUX FEED TUNNEL COVERS INSTALLATION 1.1 IR #: 653093, 620080, 789344, 783811, 792213 and 790428 1.2 OpEval #: 07-006 Revision: 67 General Information: 1.3 Affected Station(s): Byron 1.4 Unit(s): 1 and 2 1.5 System: DS 1.6 Component(s) Affected: Unit 1 and 2 Aux. Feed Tunnel Flood Seals. 1.7 Detailed description of what SSC is degraded or the nonconforming condition, by what means and when first discovered, and extent of condition for all similarly affected SSCs: The flood seal covers and support elements for Aux. Feed Tunnels (1/2DSFS006/07/08/09) do not meet the design basis requirements for their as installed configurations for High Energy Line Break (HELB) loading. This condition has been identified in IR's 653093 and 620080. Further evaluation as documented in EC 366723 (Attachment-A) indicates that a HELB pressure of 17.7 psi on the subject covers and supporting elements would be acceptable for the system Operability Evaluation. This condition is applicable to all of the covers for the Aux. Feed tunnels as included in the AEL of this EC. Revision 1 shows CA's #1 and 2 as COMPLETE and adds CA's #3 through 10. The new CA's will track completion of EC's for each MSIV Rooms flood seals and completion of the WO's to modify them per the EC's. There are no changes to the operability determination or engineering support. Revision 2 shows CA's #3 and 4 as COMPLETE and revises the due dates for CA's #7 and 8 for installation of U-1 to 06/06/08. Installation of U-1 was planned for the first week of May, 2008, but was not performed due to concerns that the work could not be completed within the allowed LCOAR time and may have to be moved into outage B1R16. IR 764527 was written documenting these concerns, and ATI 764527-02 to Design Engineering is tracking resolution, due 05/30/08. Therefore, it is expected that CA's #7 and 8 may require extension again once these concerns have been worked out and new installation dates can be determined. Revision 3 addresses the impact of an issue (IR 789344, Ref 2.5.3.13) associated with the discovery that plates installed next to the MSIV room ventilation fan discharge dampers, that were assumed to be blow-out plates by the pressurization calculation, were in fact blank-off plates, not blow-out panels. The vent area assumed in Reference 2.5.3.10 was 51.3 ft2 per MSIV room. Further review by Engineering resulted in IR 790428 (Ref 2.5.3.18) that documents the potential for insufficient margin with respect to AF FSO structural integrity. Revision 3 also addresses using Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 2 dynamic loading factors (DLFs) on the FSO supporting structure concrete expansion anchors. (Reference 2.5.3.24) Revision 4 shows CA # 11 as Complete. New FSO covers will be installed per the CA's currently assigned, using a bounding pressure assumption. CA # 11 created several interim ACITs to complete a new mass and energy release analysis and a steam tunnel pressurization analysis. It also created a new CA #12 to verify that the new FSO cover design has restored the required factors of safety prior to closing this Op Eval. Revision 5 extends the due dates of CA's #7, 8, 9, and 10 to 03/31/09 and CA #12 to 04/10/09. It also adds a requirement to CA #12 to determine if the Blow-out panel TCCP's can be removed or must be made permanent. There are no technical changes. The most recent plan had been to perform the Unit 2 modifications in B2R14, and the Unit 1 modifications the following month. However, a management decision was made to not perform the Unit 2 work as originally planned due to resources. The work was SCRF'd out of B2R14. Revisions required to the mod EC's are not completed to support the work. This is due in part to NRC Generic Letter 08-01 on gas voiding concerns. There is information as well that the EC's will provide a product that will not challenge LCO time to perform the work on line. The first opportunity to perform this work is in March 2009. MRC approved this extension on 9/30/08. Revision 6 shows CA's 7, 8, 9, 10, and Comp Action #4 as Complete. These actions installed the final AF tunnel covers and TCCP's to change the blank-off plates to blow-out panels. It adds CA #13, which will track making the Blowout panel TCCP's permanent modifications. Completion of this CA will allow closure of this Op Eval. Revision 7 shows CA's 12 and 13 as complete. It also removes the "Complete to Close EC" checkmark in Passport for TCCP EC 371279. TCCP EC 371279 installed temporary AF tunnel covers. To install some of the bracing supporting the temporary cover installation, a sound-powered phone conduit was cut. The temporary cover and bracing has been physically removed, but EC 371279 is remaining open because the conduit has not yet been repaired or permanently accepted as-is. EC 367211 has been initiated and associated to EC 371279 to repair the conduit or accept it's current condition permanently. Because the conduit is appropriately sealed, it does not impact the ability of the AF Tunnel Covers to perform their function, and thus EC 371279 is not required to be completed in order to close this Op Eval. 2.0 EVALUATION: 2.1 Describe the safety function(s) or safety support function(s) of the SSC. As a minimum the following should be addressed, as applicable, in describing the SSC safety or safety support function(s): -Does the SSC receive/initiate an RPS or ESF actuation signal? No, the cover's function is to protect the Aux. Feed Tunnel from flooding and protect the equipment from adverse loading. It is a passive component. -Is the SSC in the main flow path of an ECCS or support system? No, the covers are located in MSIV rooms. -Is the SSC used to:
Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Maintain reactor coolant pressure boundary integrity? No. Shutdown the reactor? No Maintain the reactor in a safe shutdown condition? No. Page: 3 in Prevent or mitigate the consequences of an accident that could result off site exposures comparable to 10 CFR 50. 34 (a) (1), 10 CFR 50. 67 (b) (2), or 10 CFR 100.11 guidelines, as applicable. Yes. The cover protects the valves (1/2AF013A-H) located inside the tunnel from any harsh environment. -Does the SSC provide required support (i.e., cooling, lubrication, etc.) to a TS required SSC? No. -Is the SSC used to provide isolation between safety trains, or between safety and non-safety ties? No. -Is the SSC required to be operated manually to mitigate a design basis event? No. -Have all safety functions described in TS been included? Yes Have all safety functions of the SSC required during normal operation and potential accident conditions been included? Yes -Is the SSC used to assess conditions for Emergency Action Levels (EALs)? No. 2.2 Describe the following, as applicable: (a) the effect of the degraded or nonconforming condition on the SSC safety function(s); The concern is that the covers and supporting elements do not meet the design basis for HELB loading. However, it does meet the operability requirement for the HELB loading, which is determined to be an acceptable loading, which is documented in EC 366723 (Attachment-A) The inappropriate assumption (addressed by Rev 3 of this Op Eval) that the blank off plates relieve pressure would result in higher MSIV room pressure potentially making the AF FSO inoperable. (b) any requirements or commitments established for the SSC and any challenges to these; The covers are designed to stay in place for design loading and protect the tunnel from flooding or any other harsh environment. Based on design calculations, the support members for the cover do not meet the design basis requirements for HELB loading, however, the operability criteria for the failing component of the cover support is met, which are the concrete expansion anchors that mounts the cover plate support members on the concrete wall. This evaluation showing operability acceptance is contained in EC 366723 (Attachment-A) . (c) the circumstances of the degraded/nonconforming condition, including the possible failure mechanism(s); The possible failure mechanisms is overload of the plate or supporting elements. This would allow a steam water mixture to flow to the area containing the AF013s. Although the valves are of the same type and have similar maintenance as environmentally qualified valves, the AF013s are not environmentally qualified. Therefore the harsh environment could cause the valves to fail. (d) whether the potential failure is time dependent and whether the condition will continue to degrade and/or will the potential consequences Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 4 increase; The potential failure is not time dependent. The condition will not continue to degrade and the potential consequences will not increase. (e) the aggregate effect of the degraded or nonconforming condition in light of other open OpEvals: There are currently nine other open Op Evals that impact Byron Unit 1 and 2. However, none of these are associated with the Aux. Feed Tunnel cover, and there is no adverse aggregate effect of these nine open Op Evals on this issue, or vice-versa. 2.3 Is SSC operability supported? Explain basis YES (e.g., analysis, test, operating experience, engineering judgment, etc.): EC 366723 (Attachment-A) contains the evaluation that shows the cover support members would meet the operability criteria for revisions of this Op Eval through Rev 3. To estimate the impact of the reduction in vent area in Rev 3 of the Op Eval, Sargent and Lundy (S&L) was contacted to perform study runs on each unit. These study runs had the following attributes: -The software program used (RELAP) is accepted by the industry for this type of analysis and is the same software used in Reference 2.5.3.10, -S&L has an approved QA program and the software was run from a controlled location, The runs were performed by a qualified analyst with oversight from a senior engineer, -Inputs were developed with input from Byron, Braidwood and Corporate Engineering. The following are the significant changes to the model used in Reference 2.5.3.10: Credit was taken for more realistic mass and energy release, (Ref 2.5.3.21) -The vent paths from the MSIV room to the Main Steam Tunnel were more accurately modeled (pressure penalty), -Credit was taken for the openings created under References 2.5.3.14 and 2.5.3.15. Credit was taken for the annular flow area between the MSIV fan motor and fan shroud. Note that no credit was taken for the fan running. Security bars were modeled as partial flow obstruction. Credit was taken for flow path of normally open dampers on fan discharge (after adjusting for the obstruction due to thickness of the damper blades). The model was run in an iterative manner where Byron and Braidwood Engineering discussed the effects of the changes for impact and reasonableness with S&L. Based on the S&L study runs, the peak pressure in the MSIV room after accounting for the above model changes was 21.7 psig for Unit 1 and 19.4 psig for Unit 2. (Reference 2.5.3.19) Since the pressures have changed, new dynamic load factors were determined by S&L and provided in Reference Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 5 2.5.3.22. Note that work is in progress to install stiffeners on the AF FSO plates and that the DLFs only represent the AF FSO plates prior to the installation of the stiffeners. On Unit 1, two Temporary Configuration Changes (TCC) were installed to enhance a degraded but operable condition; removal of the blank off plates (Ref 2.5.3.15) and strengthening of the AF FSO covers (Ref 2.5.3.16). The design of the stiffener TCC on Unit 1 used a peak pressure of 20 psig and DLF of 2.0 (Reference 2.5.3.20). As the TCC was being installed, Sargent and Lundy provided additional information that the peak pressure was 21.7 psig, instead of the 20 psig used for the design of the TCC. (This occurred due to the parallel paths of refining the analysis and installing the TCC.) The calculation (Reference 2.5.3.20) used to develop the factors of safety for the TCC was reviewed; adequate margin exists to compensate for the increased pressure and still assure operability of the AF FSO Concrete Expansion Anchors with a factor of safety greater than 2.0. A finite element analysis of the plate itself shows that the plate would remain intact (Reference 2.5.3.17). Therefore the Unit 1 AF013s should be considered operable with the enhanced margin gained by the two TCCs. For Unit 2 the blowout panel TCC has been installed, but Unit 2 is different than Unit 1 in two other aspects; the tube steel stiffeners have not yet been installed and the peak pressure in the MSIV rooms are lower. The pressures are lower due to different mass and energy releases resulting from differences in SG design. These offsetting factors have been reviewed in Reference 2.5.3.17 and the factor of safety for the CEAs is 1.35. This is sufficiently (but subjectively) greater than 1 that operability is assured on Unit 2 by only crediting the blowout panel TCC. The stiffener TCC is being installed to increase margin. If 2.3 =NO, notify Operations Shift Management inunediately. If 2.3 = YES, clearly document the basis for the determination. 2.4 Are compensatory and/or corrective actions required? YES Corrective action is in place to install modifications that would ensure full design basis compliance. Compensatory measures are required to ensure that factors of safety remain within acceptable limits. If 2.4 = YES, complete section 3.0 (if NO, N/A section 3.0). 2.5 Reference Documents: 2.5.1 Technical Specifications and Bases Section(s): 2.5.1.1 3.7.5 Aux. Feedwater System 2.5.2 UFSAR Section(s): 2.5.2.1 3.6, Attachment C3.6, Main Steamline Break in Main Steam Tunnel 2.5.2.2 3.6 Protection Against Dynamic Effects Associated with the Postulated Break of Piping 2.5.2.3 3.11 Environmental Design of Mechanical and Electrical Equipment 2.5.2.4 15.1.5 Steam System Piping Break at Zero Power 2.5.2.5 15.1.6 Steam System Piping Break at Full Power 2.5.3 Other:
Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Drwg S-895, Rev AA. Drwg S-896, Rev. u Drwg S-969 Rev. AA Drwg S-970, Rev AB Drwg S-1093, Rev. Q Drwg S-1062, Rev. x Drwg S-1502, Rev. G Drwg S-1088, Rev. H Cale. 5.6.3, Rev. 005 Cale. 3C8-0282-001, Rev. 003 IR 653093 IR 620080 IR 789344 Page: 6 2.5.3.1 2.5.3.2 2.5.3.3 2.5.3.4 2.5.3.5 2.5.3.6 2.5.3.7 2.5.3.8 2.5.3.9 2.5.3.10 2.5.3.11 2.5.3.12 2.5.3.13 2.5.3.14 EC 371272 Temporary Modification Of Damper Blankoff Plate In Safety Valve Room Roof, Unit 2, Rev 0 2.5.3.15 EC 371267 Temporary Modifications Of Blankoff Plate In Safety Valve Room, Unit 1, Rev 0 2.5.3.16 EC 371278, Auxiliary Feedwater Tunnel Flood Seal Covers Bracing (Unit 1) For High Energy Line Break (HELB) Loading (TCCP), Rev 3 2.5.3.17 EC 366723, Evaluation Of Auxiliary Feedwater Tunnel Flood Barrier For HELB Loads -Operability Review, Rev 2 2.5.3.18 IR 790428 2.5.3.19 S&L DIT S040-BYR/BRW-8013, Analysis of Line Break in Lower Safety Valve Room, 7/1/08 2.5.3.20 Calculation 5.6.3.9-BYR08-068, Rev 1 2.5.3.21 IR 792213 2.5.3.22 S&L DIT S040-BYR/BRW-8012, Aux Feedwater Tunnel Operability for Byron and Braidwood, 7/1/08 2.5.3.23 EC 371279, Auxiliary Feedwater Tunnel Flood Seal Covers Bracing (Unit 2), Rev 1. 2.5.3.24 IR 783811 3.0 ACTION ITEM LIST: If, through evaluating SSC operability, it is determined that the degraded or nonconforming SSC does not prevent accomplishment of the specified safety function(s) in the TS and the intention is to continue operating the plant in that condition, then record below, as appropriate, any required compensatory actions to support operability and/or corrective actions required to restore full qualification. For corrective actions, document when the actions should be completed (e.g., irrunediate, within next 13 week period, next outage, etc.) and the basis for timeliness of the action. Corrective action timeframes longer than the next refueling outage are to be explicitly justified as part of the OpEval or deficiency tracking documentation being used to perform the corrective action. Corrective Action #1: Determine scope and extent of change (modification), Get installation estimate. Feed this info to WC for their ATI.
Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Responsible Dept./Supv.: Action Due: Complete Page: 7 Basis for timeliness of action: degradation concern with this issue. of time. There is no time-dependent The due date is a reasonable amount Action Tracking #: 653093-03 Corrective Action #2: Determine installation completion date and generate appropriate corrective Responsible Dept./Supv.: Action Due: actions. Work Control.tlllllllllllll Complete Basis for timeliness of action: degradation concern with this issue. of time. There is no time-dependent The due date is a reasonable amount Action Tracking #: 653093-04 Corrective Action #3: design. Complete EC 367209 for AF tunnel Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: Some time is required to design a change to the tunnel covers. There is no time-dependent degradation concern with this issue. Action Tracking #: Corrective Action #4: design. Responsible Dept./Supv.: Action Due: 653093-05 Complete EC 367210 for AF tunnel Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-06 Corrective Action #5: design. Complete EC 367211 for AF tunnel Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-07 Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 8 Corrective Action #6: design. Complete EC 367212 for AF tunnel Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-08 Corrective Action #7: 1061688. Responsible Dept./Supv.: Action Due: Modify U-1 AF Tunnel covers per WO Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-09 Corrective Action #8: 1061690. Responsible Dept./Supv.: Action Due: Modify U-1 AF Tunnel covers per WO Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-10 Corrective Action #9: 1061693. Responsible Dept./Supv.: Action Due: Modify U-2 AF Tunnel covers per WO Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-11 Corrective Action #10: 1061694. Responsible Dept./Supv.: Action Due: Modify U-2 AF Tunnel covers per WO Complete Basis for timeliness of action: change to the tunnel covers. Some time is required to design a There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-12 Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 9 Corrective Action #11: Determine course of action to align the physical plant and the licensing basis. (analysis, physical changes, UFSAR/licensing changes etc). Create additional actions as required. Responsible Dept. /Supv.: Action Due: COMPLETE Basis for timeliness of action: The knowledge regarding AF FSOs is evolving. Time is needed to determine the best solution. There is no time-dependent degradation concern with this issue. Action Tracking #: 653093-13 Corrective Action #12: After installation of the final tunnel cover design as documented in CAs 653093-09, 10, 11, 12, verify that the factor of safety for all components has been restored to the design values, there are no holds I unverified assumptions associated with the design, and the Op Eval actions have been completed. If any of these actions are not complete, create a new corrective action to track completion. Determine if the Blow-out panel TCCP's may be removed or must be made permanent. If they must be made permanent, create new corrective actions to track completion. Responsible Dept./Supv.: Action Due: 04/10/09Complete Basis for timeliness of action: This date is the several weeks after the final CA dates for installation of the FSO covers to allow time to perform it following installation of the new covers. Action Tracking #: 653093-17 Corrective Action #13: Ensure TCCPs 371267 & 371272 (Ul & U2 valve rooms' blow-out panels) are converted into permanent modifications. Responsible Dept. /Supv.: Action Due: 06/30/09Complete Basis for timeliness of action: All physical plant changes to resolve this issue have been completed. The blowout panels are already installed under TCCP's. This action is administrative to make them permanent. Action Tracking #: 653093-18 Compensatory Measure #1: Install TCC for Unit 1 Blank Off Panels (EC 371267). Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: enhance margin to operability. Complete. Action Tracking #: N/A Performed on expedited basis to Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Page: 10 Compensatory Measure #2: Install TCC for Unit 2 Blank Off Panels (EC 371272) . Responsible Dept./Supv.: Action Due: margin to operability. Performed on expedited basis to enhance Complete Basis for timeliness of action: Complete Action Tracking #: N/A Compensatory Measure #3: (EC 371278) Install TCC for Unit 1 AF FSO Bracing Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: enhance margin to operability. Performed on expedited basis to Action Tracking #: N/A Compensatory Measure #4: (EC 371279) Install TCC for Unit 2 AF FSO Bracing Responsible Dept./Supv.: Action Due: Complete Basis for timeliness of action: Performing on expedited basis to enhance margin to operability. Action Tracking #: 653093-14 (In progress) 4.0 SIGNATURES: 4.1 Preparer(s) See Milestone I See Milestone 110 Date I Date 4.2 Reviewer Ssee Milestone I See Milestones Date (10 CFR 50.59 screener qualified or active SRO license holder) 3rd Party Date Review N/A I See Milestones 4.3 Sr. Manager Design Engg/Designee Concurrence See Milestones Date 4.4 Operations Shift Management Approval See Milestones Date 4.5 Ensure the completed form is forwarded to the OEPM for processing and Action Tracking entry as appropriate. 5.0 OPERABILITY EVALUATION CLOSURE: 5.1 Corrective actions are complete, as necessary, and the OpEval is ready for closure I See Milestones Date (OEPM)
Engineering Change Print Date: 08/31/2017 EC Number : .....,, Facility : Type/Sub-type: 0000366685 007 BYR OPEV Exelon. Date 5.3 5.2 Page: 11 Operations Shift Management Approval /See Milestones Ensure the completed form is forwarded to the OEPM for processing, Action Tracking entry, and cancellation of any open compensatory actions, as appropriate.