ML092740624
ML092740624 | |
Person / Time | |
---|---|
Site: | Oconee ![]() |
Issue date: | 09/29/2009 |
From: | Baxter D Duke Energy Carolinas |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
Download: ML092740624 (37) | |
Text
Duke 6Energy DAVE BAXTER Vice President Oconee Nuclear Station Duke Energy ONO0 VP / 7800 Rochester Highway Seneca, SC 29672 864-873-4460 864-873-4208 fax September 29, 2009 dabaxter@dukeenergy.com U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555
Subject:
Duke Energy Carolinas, LLC Oconee Nuclear Station, Units 1, 2, and 3 Docket Numbers 50-269, 50-270, and 50-287 Request for Additional Information regarding the License Amendment Request to adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants (2001 Edition)
License Amendment Request (LAR) 2008-01 In accordance with 10 CFR 50.90, Duke Energy Carolinas, LLC (Duke) proposes to amend Renewed Facility Operating Licenses (FOLs) Nos. DPR-38, DPR-47, and DPR-55. This LAR requests Nuclear Regulatory Commission (NRC) review and approval for adoption of a new fire protection licensing basis which complies with the requirements in 10 CFR 50.48(a), 10 CFR 50.48(c), and the guidance in Regulatory Guide (RG) 1.205. The LAR was submitted to the NRC on October 31, 2008 and supplemented in letters dated January 30, 2009, February 9, 2009, February 23, 2009, May 31, 2009, and August 3, 2009.
In Duke's August 3, 2009 response to an NRC request for additional information (RAI), Duke committed to provide the response to RAI 6-1 and when the Oconee Fire PRA Application Calculation is complete, finalize responses to RAIs 1-2, 5-5, and 5-11. Enclosure 1 provides the answer to RAI 6-1. The Oconee Fire PRA Application Calculation has been completed and no changes are required to RAIs 1-2 and 5-11. Therefore, the August 3, 2009 responses provided to RAIs 1-2 and 5-11 are now considered final. RAI 5-5 is not final and requires revision to address new methodologies associated with recovery action classification discussed below. RAI 5-5 will be updated in the response due January 31, 2010.
Preliminary responses were also provided to RAIs 5-4, 5-6, and 5-8 in Duke's August 3, 2009 response. No change is required to RAI 5-4 as a result of the completed Oconee Fire PRA Application Calculation. Therefore, the August 3, 2009 response provided to RAI 5-4 is now considered final. Enclosure 1 contains the finalized answers associated with RAIs 5-6 and 5- -
- 8. Changes from the previous version are denoted by revision bars. The Oconee Fire PRA Application Calculation will be posted to the shared website for reference.
Commitments are provided in Attachment 1. The commitments associated with revising the Transition Report submitted October 31, 2008, the IN 92-18 study results, and FAQ 07-30 resolution have been revised to reflect the project schedule which is posted on the shared website for reference. The new date reflects the work that is to be done as a result of working A'A www. duke-energy corn
U. S. Nuclear Regulatory Commission September 29, 2009 Page 2 towards resolution of FAQ 07-30 issues. Duke will pilot, per NRC request, new methodologies with respect to primary control stations, circuit analysis, and recovery action classification. These new methods are described in DG-1214, DG-1218, and NEI 00-01, revision 2.
If there are any questions regarding this submittal, please contact Reene' Gambrell at (864) 873-3364 or David J. Goforth at (704) 382-2659.
I declare under penalty of perjury that the foregoing is true and correct. Executed on September 29, 2009.
Sincerely, Dave Baxter, Vice President Oconee Nuclear Station
Enclosure:
- 1. Request for Additional Information regarding the License Amendment Request to adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants (2001 Edition)
Attachment:
- 1. Commitments
U. S. Nuclear Regulatory Commission September 30, 2009 Page 3 cc: w/o enclosures Mr. John Stang, Project Manager Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop 0-8 G9A Washington, D. C. 20555 Mr. Luis Reyes, Regional Administrator U. S. Nuclear Regulatory Commission - Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. Paul Lain, NFPA-805 Program Manager Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop 0-10 C15 Washington, D. C. 20555 Mr. Andrew Sabisch Senior Resident Inspector Oconee Nuclear Station Ms. Susan Jenkins, Manager Infectious and Radioactive Waste Management Section 2600 Bull Street Columbia, SC 29201
Enclosure 1 REQUEST FOR ADDITIONAL INFORMATION REGARDING THE LICENSE AMENDMENT REQUEST TO ADOPT NFPA 805 PERFORMANCE-BASED STANDARD FOR FIRE PROTECTION FOR LIGHT WATER REACTOR GENERATING PLANTS (2001 EDITION)
- Request For Additional Information September 29, 2009 Page 1 of 29 ENCLOSURE I REQUEST FOR ADDITIONAL INFORMATION REGARDING THE LICENSE AMENDMENT REQUEST TO ADOPT NFPA 805 PERFORMANCE-BASED STANDARD FOR FIRE PROTECTION FOR LIGHT WATER REACTOR GENERATING PLANTS (2001 EDITION)
RAI 5-6:
Provide justification for only providing listings for fire initiating events representing 50% of CDF in Table W-1 of the TR or justify a level of additional initiators that contribute to risk (CDF and LERF).
RAI 5-6 RESPONSE:
Since there are no existing regulatory requirements or guidance on providing fire risk insights in the LAR TR, a decision was made to provide fire initiating events representing 50% of CDF in Table W-1 of the TR. The 50% threshold decision did not have a documented technical basis and was based on judgment. A revision to ONS calculation OSC-9518, NFPA 805 FPRA Application Calculation, addresses the compilation of insights from scenarios that are significant contributors to risk. According to the definition of "significant" in Section 1.2-2 of the ASME Standard relative to CDF (ASME-ANS RA-S-2008), the fire initiating events that sum to 95% of CDF collectively or those that contribute more than 1% of the total fire CDF are considered to represent the significant fire scenarios. There are 50 scenarios comprising 90% of the cumulative fire CDF. Of these, 31 scenarios contribute less than 1% on an individual basis.
Therefore, the scenarios comprising 90% of CDF are considered sufficient for developing insights.
The updated table from a revision of ONS calculation OSC-9518 has been attached. These results are subject to change as the FPRA calculation revisions initiated to address recent changes in the list of committed modifications undergo final approval. As discussed in response to RAI 5-5, insights from the LERF results are also included in the update to ONS calculation OSC-9518.
Enclosure 1: Request For Additional Information September 29, 2009 Page 2 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF CR03W1 MCB Fire - CR 12.3% / 12.3% Scenario takes no credit for Aux Shutdown Panel; 1.8E-01 3.2E-05 5.3E-06 Abandonment failures were assumed which virtually eliminated all success paths other than SSF mitigation. Dominant sequences involve fire or transient induced stuck open pressurizer PORV with loss of HPI. Loss of SSHR sequences make a small contribution.
AB101E Cabinet EPSL (LS) Fire 9.6% / 21.9% Internal cabinet failures include MFB 1 & 2. Other 5.OE-02 8.1E-05 4.1E-06 than the additional power source for the SSF, PSW is also assumed to be failed. The risk is dominated primarily by loss of SSHR sequences but seal LOCA sequences are also important. Random failures of the TDEFW, failure to align EFW from another unit and SSF failures lead to core damage.
U3TB29B1 3TC Switchgear - Severe 8.2% / 30.1% In addition to the loss of 3TC, tray damage resulting 8.5E-03 4.1E-04 3.5E-06 Fire in turbine driven EFW pump failure, and loss of all HPI due to loss of power and LPSW failures.
Dominant sequences are loss of SSHR with failure of HPI forced cooling. Overcooling events leading to HPI actuation and stuck open pressurizer relief valve make a small contribution. Note that 3TD has been excluded from failure via tray damage by crediting reroute of cables 3EPTD105 & 3EPTD1404; without the reroute, failure of 3TD is offset by the planned installation of MSIVs.
Enclosure 1: Request For Additional Information September 29, 2009 Page 3 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB101BI Aux BchBd 3AT1 Fire 8.1% / 38.2% Internal cabinet failures include MFB 1 & 2. Other 8.5E-03 4.OE-05 3.5E-06 than the additional power source for the SSF, PSW is also assumed to be failed. The risk is dominated primarily by loss of SSHR sequences but seal LOCA sequences are also important. The TDEFW pump is failed by the fire. Failure to align EFW from another unit and SSF failures lead to core damage.
AB101B2 Aux BchBd 3AT2 Fire 7.8% / 46.0% Internal cabinet failures include MFB 1 & 2. Other 8.2E-02 4.OE-05 3.3E-06 than the additional power source for the SSF, PSW is also assumed to be failed. The risk is dominated primarily by loss of SSHR sequences but seal LOCA sequences are also important. The TDEFW pump is failed by the fire. Failure to align EFW from another unit and SSF failures lead to core damage.
AB098B AHU 3-6 Fire 2.9% / 48.9% This scenario is dominated by a fire induced loss of 7.5E-03 1.7E-04 1.2E-06 condenser vacuum initiating event, loss of RCP seal cooling, spurious RCP start, and loss of the RBCUs.
Unavailability of the SSF, leads to a consequential RCP seal LOCA. Mitigation fails due to various sump recirculation failures.
Enclosure 1: Request For Additional Information September 29, 2009 Page 4 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF CR03F MCB Fire - 3AB1 (MFB 1 2.7%/ 51.6% Internal cabinet failures include 3TC, 3TD, & 3TE, 5.5E-02 2.1E-05 1.2E-06
& 2) and 3MS VA0126 & 129. Other than the additional power source for the SSF, PSW is also assumed to be failed. The risk is dominated primarily by loss of SSHR sequences but seal LOCA sequences are also important. Random failures of the TDEFW, failure to align EFW from another unit and SSF failures lead to core damage. Very small contributions from overcooling transients and spurious RCP starts are also present.
CR03H MCB Fire - 3EB1 thru 2.5% / 54.1% This scenario is dominated by a fire induced loss of 5.2E-02 2.1E-05 1.1E-06 3EB4 condenser vacuum initiating event, loss of all ac power and PSW supply to HPI. The risk is dominated primarily by loss of SSHR sequences but seal LOCA sequences are also important. Random failures of the TDEFW, failure to align EFW from another unit and SSF failures lead to core damage.
AB101V CRD V Reg I Xfmr Fire 2.3%/ 56.4% This scenario is dominated by a fire induced loss of 1.6E-03 6.3E-04 9.8E-07 condenser vacuum initiating event, loss of the pressurizer heaters, RCP seal injection, and loss of the RCBUs. The sequences are split between overcooling events which result in unthrottled HPI and stuck open pressurizer relief valves and seal LOCAs. Mitigation fails due to failure to successfully establish sump recirculation.
Enclosure 1: Request For Additional Information September 29, 2009 Page 5 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB089C1 LC 3X9 Severe Fire 2.2% / 58.7% This scenario is dominated by a fire induced loss of 9.3E-03 1.OE-04 9.5E-07 condenser vacuum initiating event, draining of the BWST, loss of LPSW, instrument air, EFW, PSW, and the PORV block valve. Failure of EFW cross-connect and SSF ASW leads to a total loss of SSHR. Stuck open pressurizer PORV sequences are also important. Mitigation fails due to the loss of ECCS pumps as a consequence of the draining.
CR03D MCB Fire - 3UB1 with 2.1% / 60.8% This scenario is dominated by fire induced opening 1.3E-01 7.OE-06 9.2E-07 LPI (no EFDW impact) of the pressurizer PORV or transient induced stuck open PORV, loss of the pressurizer PORV block valve, failure of the LDST level transmitters, and LPI valves. The result is a fire induced LOCA with failure to achieve sump recirculation. Transient (loss of condenser vacuum) loss of SSHR with failure to achieve sump recirculation is also important.
RB03D RB Fire - West Half 2.0% / 62.8% This scenario is dominated by a fire induced reactor 2.1E-03 4.2E-04 8.5E-07 trip initiating event, fire induced spurious pressurizer spray, loss of the pressurizer heaters, loss of the SSF RCM, loss of RCP thermal barrier cooling, and inability to isolate the seal return line.
Failure of the LDST level transmitters results in a loss of RCP seal injection. An ISLOCA through the seal return line results (significant LERF contributor). Other important sequences include fire induced pressurizer PORV opening or transient induced stuck open PORV with failure of sump recirculation.
Enclosure 1: Request For Additional Information September 29, 2009 Page 6 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB089B2 LC 3X8 Non-Severe Fire 1.9% / 64.7% This scenario is dominated by a fire induced loss of 3.2E-03 3.2E-04 8.2E-07 condenser vacuum initiating event, spurious draining of the BWST, loss of various ECCS valves, the PORV block valve, and a loss of instrument air.
Failure of EFW leads to a stuck open pressurizer PORV. Mitigation fails due to the BWST draining and consequential loss of the ECCS pumps.
Overcooling transients with a stuck open PORV are also important.
HPH03B Fiber Optic Cabinet Fire 1.8% / 66.6% Fire induced failure of CC Pumps 3A & 3B, 3LP 1.9E-02 4.OE-05 7.8E-07 VA0019 & 20, and loss of LDST cooling coupled with SSF maintenance failure results in a seal LOCA with subsequent failure to go into recirculation mode.
CR03W2 Non MCB Fire - CR 1.7%/ 68.3% This scenario is dominated by a fire induced loss of 2.1E-01 3.4E-06 7.2E-07 Abandonment condenser vacuum initiating event, fire induced loss of all ac power, EFW, and PSW. Mitigation fails due to SSF failure.
Enclosure 1: Request For Additional Information September 29, 2009 Page 7 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF U2TB15C1 Main FDW Pump 2B Fire 1.6%/ 69.9% This scenario is dominated by a fire induced loss of 4.8E-02 1.5E-05 7.OE-07
- Non Suppression condenser vacuum initiating event, loss of all ac power, the TDEFW pump and EFW cross-connect.
Failure of the SSF and PSW leads to a loss of all SSHR, RCP seal LOCA sequences make a small contribution. Mitigation fails due to the loss of power.
U2TB15B1 Main FDW Pump 2A Fire 1.6% / 71.5% This scenario is dominated by a fire induced loss of 4.8E-02 1.5E-05 7.OE-07
- Non Suppression condenser vacuum initiating event, loss of all ac power, the TDEFW pump and EFW cross-connect.
Failure of the SSF and PSW leads to a loss of all SSHR, RCP seal LOCA sequences make a small contribution. Mitigation fails due to the loss of power.
UITB19C1 Main FDW Pump 1B Fire 1.6% / 73.2% This scenario is dominated by a fire induced loss of 4.8E-02 1.5E-05 7.OE-07
- Non Suppression condenser vacuum initiating event, loss of all ac power, the TDEFW pump and EFW cross-connect.
Failure of the SSF and PSW leads to a loss of all SSHR; RCP seal LOCA sequences make a small contribution. Mitigation fails due to the loss of power.
Enclosure 1: Request For Additional Information September 29, 2009 Page 8 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB101H Cabinet SGLC-3 Fire 1.2% / 74.3% This scenario is dominated by a fire induced loss of 4.1E-03 1.2E-04 4.9E-07 MFW initiating event, fire induced loss of instrument air, the EFW pumps, the RBCUs, and PSW. Failure of the EFW cross-connect and the SSF ASW leads to loss of SSHR. Various failures lead to loss of sump recirculation.
AB101K1 Keowee ES Ch A Cabinet 1.0% / 75.3% This scenario is dominated by a fire induced loss of 1.1E-02 4.OE-05 4.3E-07 Fire MFW initiating event, fire induced loss of LPSW, PSW, instrument air, and failure of the turbine to trip. Failure of the LPSW cross-connect, failure of EFW cross-connect,.and SSF ASW leads to a loss of SSHR. Mitigation fails at sump recirculation due to the loss of LPSW.
AB101B3 Aux BchBd 3AT3 Fire 1.0% / 76.3% This scenario is dominated by a fire induced loss of 1.OE-02 4.OE-05 4.1E-07 condenser vacuum initiating event, fire induced loss of LPSW, the RBCUs, PSW, TDEFW pump, and a failure to trip the turbine. Failure of the EFW and LPSW cross-connects, and SSF ASW leads to a loss of all SSHR. Mitigation fails at sump recirculation due to the loss of LPSW. An overcooling transient which initiates HPI and leads to a stuck open PZR safety valve makes a smaller but important contribution.
Enclosure 1: Request For Additional Information September 29, 2009 Page 9 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF CR03J ICS Cabinet Fire 0.9% / 77.2% This scenario is dominated by a fire induced loss of 7.OE-04 5.7E-04 4.OE-07 MFW initiating event, fire induced loss of LPSW, RCP seal injection, pressurizer spray actuation, PSW, and spurious RCP restart. HPI actuation as a result of spurious spray with failure to throttle leads to a stuck open PZR relief valve. Failure to cross-connect LPSW leads to a loss of sump recirculation capability. Loss of SSHR and seal LOCAs make smaller contributions.
CR03G2 MCB Fire - 3VB2 & 3VB3 0.9% / 78.1% This scenario is dominated by a fire induced loss of 1.8E-02 2.1E-05 3.8E-07 condenser vacuum initiating event, fire induced draining of the BWST, failure of the turbine trip, loss of the RBCUs, spurious RCP restart, and loss of the EFW pump. Loss of SSHR occurs due to failure to cross-connect EFW and failure of the SSF-ASW.
Mitigation fails due to BWST draining.
AB101T1 3ESTC1 Cabinet Fire 0.8% / 79.0% This scenario is dominated by a fire induced 8.6E-03 4.OE-05 3.5E-07 inadvertent engineered safeguards initiating event, loss of LPSW, instrument air, and the RBCUs.
Failure to throttle HPI results in a stuck open pressurizer relief valve. Failure to cross-connect LPSW fails mitigation.
Enclosure 1: Request For Additional Information September 29, 2009 Page 10 of 29 ONS Significant Fire Initiating Events (Representing 900/a of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB089B1 LC 3X8 Severe Fire 0.8% / 79.8% This scenario is dominated by a fire induced loss of 3.3E-03 1.0E-04 3.3E-07 condenser vacuum initiating event, loss of instrument air, and draining of the BWST to the sump. Failure of a pressurizer relief valve to reseat leads to a transient induced LOCA that cannot be mitigated. Relief challenge is dominated by HPI actuation following overcooling.
U3TB06C3 Main FDW Pump 3B Fire 0.8% / 80.5% This scenario is dominated by a fire induced loss of 6.0E-02 5.6E-06 3.3E-07
- Severe main feedwater initiating event, loss of all ac power, and EFW. Failure of the SSF and PSW leads to an unmitigated loss of all SSHR.
U3TB29B2 3TC Switchgear - Non 0.7%/ 81.2% This scenario is dominated by a fire induced loss of 6.1E-04 4.8E-04 3.0E-07 Severe condenser vacuum initiating event, fire induced loss of LPSW partly due to the loss of power, and loss of instrument air. Overcooling transient which initiates HPI and leads to a stuck open PORV also make the largest contribution. Also important is failure of the LPSW and EFW cross-connects, failure of the TDEFW pump, SSF ASW, and PSW leading to a loss of SSHR or stuck open PORV. Mitigation fails at sump recirculation.
Enclosure 1: Request For Additional Information September 29, 2009 Page 11 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario I Description Contributionb Risk insights CCDP RB03E RB Fire - East Half 0.7% / 81.9% This scenario is dominated by a fire induced reactor trip initiating event, loss of the pressurizer heaters, loss of RCP thermal barrier cooling, spurious RCP start, and loss of the SSF RCM pump. Common cause failure of the N or E breakers or loss of seal injection due to various HPI failures leads to failure to mitigate a seal LOCA.
U2TB15B3 Main FDW Pump 2A Fire 0.6%/ 82.5% This scenario is dominated by a fire induced loss of
- Severe condenser vacuum initiating event, loss of all ac power, and EFW. Failure of the SSF and PSW leads to a loss of all SSHR. RCP seal LOCAs also make a small contribution.
U2TB15C3 Main FDW Pump 2B Fire 0.6% / 83.1% This scenario is dominated by a fire induced loss of
- Severe condenser vacuum initiating event, loss of all ac power, and EFW. Failure of the SSF and PSW leads to a loss of all SSHR. RCP seal LOCAs also make a small contribution.
Enclosure 1: Request For Additional Information September 29, 2009 Page 12 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF U1TB19C3 Main FDW Pump 1B Fire 0.6% / 83.8% This scenario is dominated by a fire induced loss of 4.8E-02 5.6E-06 2.7E-07
- Severe condenser vacuum initiating event, loss of all ac power, and EFW. Failure of the SSF and PSW leads to a loss of all SSHR. RCP seal LOCAs also make a small contribution.
CR03G1 MCB Fire - 3VB1 0.6%/ 84.4% This scenario is dominated by a fire induced loss of 3.6E-02 7.OE-06 2.6E-07 condenser vacuum initiating event, loss of the pressurizer heaters, and inability to establish high pressure recirculation. Failure of EFW and the SSF ASW leads to a loss of SSHR and mitigation fails at sump recirculation. Overcooling transients with a stuck open pressurizer relief valve make a small contribution.
AB101C5 Cabinet UCTC 5 Fire 0.6% / 84.9% This scenario is dominated by a fire induced loss of 5.8E-03 4.OE-05 2.4E-07 condenser vacuum initiating event, loss of 3TC and 3TD, and partial loss of instrument air. A stuck open pressurizer relief valve due to failure of EFW or an overcooling event with unthrottled HPI results.
Mitigation fails at sump recirculation due to the power failures.
Enclosure 1: Request For Additional Information September 29, 2009 Page 13 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF U3TB28B MCC 3XGA Fire 0.5% / 85.4% This scenario is dominated by a fire induced loss of 3.0E-04 7.3E-04 2.2E-07 condenser vacuum initiating event, fire induced loss of LPSW, EFW, and instrument air. Failure to cross-connect EFW, of SSF ASW, and PSW lead to a loss of SSHR. Mitigation fails at sump recirculation with failure to cross-connect LPSW.
CR031 RPS Cabinet Fire 0.5% / 85.9% This scenario is dominated by a fire induced loss of 5.5E-04 3.6E-04 2.0E-07 condenser vacuum initiating event, loss of the pressurizer heaters, and inability to establish high pressure recirculation. Overcooling or loss of PZR heaters leads to HPI actuation. Failure to throttle leading to a stuck open pressurizer relief valve results in the largest contribution. Loss of all SSHR sequences make a smaller contribution.
AB101I Transducer Term 0.4% / 86.3% This scenario is dominated by a fire induced loss of 1.6E-03 1.2E-04 1.9E-07 Cabinet (TDC) Fire Main Feedwater initiating event, loss of the pressurizer heaters, and loss of the RBCUs.
Overcooling or loss of PZR heaters leads to HPI actuation. Failure to throttle leading to a stuck open pressurizer relief valve. Various recirculation failures lead to core damage results in the largest contribution. Loss of all SSHR sequences make a smaller contribution.
Enclosure 1: Request For Additional Information September 29, 2009 Page 14 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB101M3 Cabinet 3MTC3 Fire 0.4% / 86.7% This scenario is dominated by a fire induced loss of 4.5E-03 4.OE-05 1.8E-07 condenser vacuum initiating event, loss of EFW, loss of the pressurizer PORV, PSW, instrument air and the RBCUs. Failure of the EFW cross-connect and SSF ASW leads to loss of all SSHR. Failure to establish sump recirculation fails the mitigation.
Overcooling leading to HPI actuation and a stuck open pressurizer safety valves also make a contribution.
AB106D Closed Panel 1EPSLP2 0.4% / 87.1% This scenario is dominated by a fire induced loss of 3.4E-04 4.8E-04 1.7E-07 Fire condenser vacuum initiating event, and failure of both standby buses. Transformer CT3 is unavailable and a loss of all ac power results.
Failure of EFW and the SSF ASW leads to an unmitigated loss of all SSHR. Failure of the SSF RCM leads to a seal LOCA.
U3TB06B Main FDW Pump 3A Fire 0.4% / 87.5% This scenario is dominated by a fire induced loss of 5.3E-04 2.9E-04 1.6E-07
- Severe main feedwater initiating event, and loss of EFW.
Failure of the SSF and PSW leads to a loss of all SSHR. Failure to establish sump recirculation results in failure to mitigate the event.
Enclosure 1: Request For Additional Information September 29, 2009 Page 15 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB101R1 EHC Cabinet - Severe 0.4% / 87.9% This scenario is dominated by a fire induced loss of 2.7E-01 5.6E-07 1.5E-07 Fire condenser vacuum initiating event, loss of the 4kV switchgear, loss of the pressurizer heaters, loss of TDEFW, and PSW. A stuck open PORV or failure of the SSF results in failure to mitigate the loss of power.
AB105E. Closed Panel 2EPSLP2 0.4% / 88.2% This scenario is dominated by a fire induced loss of 3.4E-04 4.4E-04 1.5E-07 Fire condenser vacuum initiating event, loss of instrument air, failure of both standby buses, and failure of the PSW power supply to HPI.
Transformer CT3 is unavailable and a loss of all ac power results. Failure of EFW and the SSF ASW leads to an unmitigated loss of all SSHR. Failure of the SSF RCM leads to a seal LOCA.
8 CR03E MCB Fire - 3UB2 with 0.3% / 8. 6 % This scenario is dominated by fire induced loss of 2.1E-02 7.0E-06 1.5E-07 HPI & PORV coolant accidents (open RV head vents or pressurizer PORV) and failure of LPI (sump recirculation). Transient (loss of condenser vacuum) induced stuck open pressurizer safety valves with failure to achieve sump recirculation make a small contribution.
Enclosure 1: Request For Additional Information September 29, 2009 Page 16 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF AB101X5 Transient Fire (Hotwork) 0.3%/ 88.9% This scenario is dominated by a spurious pressurizer 4.6E-01 2.8E-07 1.3E-07 near Covered Hatch PORV opening event, loss of 3TC and 3TD, HP-24, and BWST draining. Draining of the BWST or power failures lead to failure to mitigate the open PORV event.
U3TB38C1 T/G Hydrogen Severe 0.3% / 89.1% This scenario is dominated by a fire induced loss of 1.OE-04 1.1E-03 1.1E-07 Fire condenser vacuum initiating event, loss of EFW, and loss of instrument air. Failure of the EFW cross-connect, the SSF, and PSW result in a loss of SSHR.
Failure to initiate high pressure recirculation fails mitigation. Stuck open pressurizer relief valves make a small contribution.
AB089D Control Battery Charger 0.3% / 89.4% This scenario is dominated by a fire induced loss of 4.7E-04 2.4E-04 1.1E-07 3CA Fire condenser vacuum initiating event, draining of the BWST, loss of the PSW, and loss of instrument air.
Failure of EFW and the SSF ASW leads to a unmitigated loss of SSHR.
Enclosure 1: Request For Additional Information September 29, 2009 Page 17 of 29 ONS Significant Fire Initiating Events (Representing 90% of the Calculated Fire Risk)
Scenario Description Contributionb Risk insights CCDP IFa CDF CR12H ES Cabinet Fire (LPSW) 0.3% / 89.6% This scenario is dominated by a fire induced loss of 3.3E-04 3.2E-04 1.1E-07 condenser vacuum initiating event, loss of CT4 and CT5, loss of the PSW, and loss of instrument air.
Unavailability of CT3 leads to a loss of all ac power.
Failure of EFW and the SSF ASW leads to a unmitigated loss of SSHR. Seal LOCA sequences make a smaller but important contribution.
AB089P1 Inverter 3DIB & ADB 0.2% / 89.9% This scenario is dominated by a fire induced loss of 4.4E-03 2.4E-05 1.1E-07 Cabs 1 & 2 - Severe Fire condenser vacuum initiating event, BWST draining, loss of the TDEFW pump, loss of PSW, and loss of instrument air. Failure of EFW and the EFW cross-connect, and the SSF result in a loss of SSHR.
Mitigation fails due to the BWSY drain. Seal LOCAs make a smaller but important contribution.
AB089C2 LC 3X9 Non-Severe Fire 0.2% / 90.1% This scenario is dominated by a fire induced loss of 4.1E-04 2.5E-04 1.1E-07 condenser vacuum initiating event, draining of the BWST, loss of the PSW, and loss of instrument air.
Failure of EFW and the SSF ASW leads to a unmitigated loss of SSHR.
- a. Ignition Frequency (IF) includes severity factor and probability of non suppression, where applicable.
- b. Individual contribution followed by cumulative contribution.
- Request For Additional Information September 30, 2009 Page 18 of 29 RAI 5-8:
Provide adequate resolution of individual SR review findings and observations (F&O) for both the most recent review of the internal events PRA and the staff review of the Fire PRA. The discussions provided in the TR for many of the F&Os is not adequate to conclude if the issues have been satisfactorily resolved. ONS RAI 5-9 identifies specific internal events F&O's that require further explanation to justify that no further action is necessary, or may require modifications to the PRA. The response needs to include a detailed description of model changes made to resolve the findings and justification for how the resolutions result in the associated supporting requirement (SR) meeting the required Capability Category. Licensee needs to ensure adequate information is provided for each F&O for Staff to reach a conclusion on adequacy of the proposed/implemented resolution.
Appendices U and V to the TR identify review F&Os for the internal events and Fire PRAs.
There are 70 F&O for the internal events PRA and 51 F&Os for the Fire PRA. The provided information in the appendices is inadequate to conclude if all issues have been satisfactorily resolved consistent with the guidance of RG 1.174 and RG 1.200.
RAI 5-8 RESPONSE:
This response is confined to the review findings associated with the staff review of the FPRA.
The information relative to the internal events PRA is being compiled in response to RAI 5-9.
With regard to the internal event F&Os, the response to ONS RAI 5-9 provides further explanation on why each corresponding ASME PRA Standard supporting requirement is adequately addressed for supporting the FPRA LAR, consistent with the guidance of RG 1.174 and RG 1.200. In addition, a meeting was held with Ray Gallucci (NRC) to provide additional information on the Appendix U items. The additional information provided to Mr. Gallucci along with the responses in RAI 5-9 should be adequate for NRC staff to conclude that the F&O resolutions are satisfactory.
The objective of Attachment V was to merely provide status of the finding. For closed findings, a reference to the supporting document was provided. The NRC was provided with the supporting documents in separate submittals. Notwithstanding, as part of the update to ONS calculation OSC-9518, NFPA 805 FPRA Application, an effort has been made to elaborate on the responses.
- Request For Additional Information September 29, 2009 Page 19 of 29 The following table was extracted from a revision to ONS calculation OSC-9518, NFPA 805 FPRA Application.
Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response CS-B1-1 Breaker coordination Open Breaker coordination issue not yet study incomplete (self resolved; PIP 0-08-2444 has been identified) generated to track completion. The top 50% risk contributing scenarios involve loss of 4KV power and reliance on SSF mitigation which are not significantly impacted by additional failures due to improper breaker coordination.
CS-C4-1 Breaker coordination Open This item is the documentation component documentation of the breaker coordination issue discussed in CS-B1-1.
FQ-A2-1 Initiating events not Closed Loss of Condenser Vacuum (%T4) was defined for all fire our default initiator for the FPRA but some scenarios scenarios assumed a different initiator as discussed in the FPRA Model Development Report. The applied initiator has been added to information provided in quantification results summary table (FPRA Summary Report, Appendix A).
FQ-B1-1 Demonstrate Closed Reference IEPRA-2 below for closure of convergence for selected FPIE truncation issue. FPRA solves for truncation limit (see CCDP (prior to application of ignition IEPRA-2 for related FPIE frequency) at one order of magnitude issue) greater than FPIE. Since a typical scenario frequency is typically much less than 0.1, there is not a truncation (convergence) issue for FPRA.
FQ-Cl-1 Use of nominal HEP Closed To address the retention of additional values may result in loss cutsets, the HEP values were set to 0.1 for of cutsets before initial solve prior to application of application of recoveries (as described in FPRA Model recoveries/multipliers Development Report).
- Request For Additional Information September 29, 2009 Page 20 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response FQ-E1-1 Identification of significant Closed Risk insights from the risk significant fire contributors initiating events with identification of significant contributors have been included in the FPRA Application Calc (see Section 3).
FQ-F1-1 Improve LERF Closed Documentation concerns were largely documentation confined to LERF. Accordingly, the insights section in the FPRA Summary Report was expanded to address LERF.
Inconsistencies between LERF and CDF have been reconciled. Additionally, the risk insights section of the FPRA Application Calc and the insights section in the FPRA Summary Report have been expanded to address LERF. Also, the applied initiator has been added to information provided in the quantification results summary as discussed in response to FQ-A2-1.
FSS-A5-1 Horizontal propagation for Closed PVC jacketing impact on horizontal fire cables with PVC jackets spread is discussed in Fire Scenario (self identified) Report. While armored cables are generally considered to be non-combustible (refer to NUREG/CR-6850 Section R.4.1.4), the armored cables at Oconee have a PVC jacketing. The justification concluded that the PVC coating will not sustain propagation of fire along the armored cable for a significant distance; any horizontal fire propagation along cable trays is adequately captured within the target set of each scenario involving overhead tray failures.
- Request For Additional Information September 29, 2009 Page 21 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response FSS-C5-1 Potential for PVC pooling Closed PVC pooling issue addressed in Fire may impact assumed Scenario Report. The justification centers damage threshold on the expectation that the PVC jacket would melt and flow away creating voids for the flow of melting materials from other cables. In addition, the ridges that are characteristic of the armor jacketing provide additional free space for the flow of material. As such, it is not expected that pooling of PVC within cable trays is likely to occur even if multiple layers of armored cables exist.
FSS-D5-1 Justify use of 75% HRR Closed Justification in Fire Scenario Report for transient fires expanded; use of 75% HRR for transients is considered realistic treatment (more characteristic of actual transient fire scenarios identified in the fire events database) appropriate for PRA application.
Use of a trash bag as the transient fuel package provides a bounding characterization of the behavior of observed transient fire ignition sources but ignores the ignition element.
Consequently, while Admin controls are factored into the development of transient ignition frequencies for each compartment, the actual transient combustible loading that may be allowed or present does not directly impact the numerical results of the Fire PRA.
FSS-D6-1 Justify fire brigade Closed Developed support for fire brigade response time with response time of 20 minutes from review respect to formation of of actual fire brigade drill performance; HGL included in Fire Scenario Report.
FSS-G1-1 Multi-compartment Closed Addressed via multi-compartment analysis incomplete screening analysis added as Attachment D to Fire Scenario Report.
- Request For Additional Information September 29, 2009 Page 22 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response FSS-G2-1 Multi-compartment Closed Screening criteria added to multi-analysis screening criteria compartment discussion in Fire Scenario not defined Report.
FSS-G3-1 Multi-compartment Closed Addressed via multi-compartment analysis screening screening analysis added as Attachment D incomplete; no MCA to Fire Scenario Report; screening criteria scenarios defined for applied to all analyzed compartments with quantification the end result being that all compartments (physical analysis units) screened.
FSS-G4-1 Multi-compartment Closed Potential for fire barrier failure addressed analysis did not consider via multi-compartment screening analysis potential for barrier failure added as Attachment D to Fire Scenario Report.
FSS-G5-1 Multi-compartment Closed No active fire barriers have been credited analysis did not assess in the FPRA for limiting the zone of active fire. barriers influence; active fire barrier between BH12 and CT4 only credited for deterministic fire area boundary definition.
FSS-G6-1 Assessment of MCA Closed Addressed via multi-compartment scenarios relative to fire screening analysis added as Attachment D risk not performed to Fire Scenario Report; no additional scenarios identified for quantification.
FSS-H2-1 Document resolution of Closed Addressed in Fire Scenario report: while PVC pooling issue the PVC jacket is thermoplastic, the cable insulation within the armor is consistent with thermoset (flame retardant cross-linked polyethylene). See FSS-C5-1.
FSS-H8-1 Multi-compartment Closed Addressed via supplemental discussion analysis documentation and multi-compartment screening analysis incomplete added as Attachment D to Fire Scenario Report.
FSS-H9-1 Document justification for Closed Support for fire brigade response time of fire brigade response time 20 minutes based on review of actual fire brigade drill performance has been added to Fire Scenario Report.
- Request For Additional Information September 29, 2009 Page 23 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response HR-G7-1 Dependencies should be Closed Corrective Action 2 of PIP 0-08-2915 reviewed with respect to dispositions issue as minimally timing conservative (compared to other sources of conservatism in FPRA) based on the degree of dependency between actions with different available response times.
HRA-A1-1 SR considered met but Closed Discussion relative to reliance on EOP, documentation that safe AOP, and alarm response procedures shutdown actions carried given a fire has been added to FPRA over from FPIE model Model Development report (see HRA-E1-remain valid for FPRA 1).
was not provided HRA-B2-1 HRA documentation for Open No impact on quantification; Corrective CASWHPIDHE and Action 3 of PIP 0-08-2915 indicates that CEFOASWDHE documentation deficiency will be insufficient addressed with issuance of future Revision 4 of the ONS PRA Model.
HRA-C1-1 Need to consider relative Closed Risk significant HFE's revisited with timing of HFE in fire respect to timing of cues; documentation scenario; time from cue provided in FPRA Model Development versus time from fire Report.
HRA-C1-2 Post-initiator HEP Closed Top 6 risk significant operator actions in quantifications need to be the FPRA were checked for consistent checked for consistency application of criteria (Corrective Action 4 of PIP 0-08-2915). The following operator actions were reviewed: TTRHPITDHE was compared to CHPHPMUDHE, HHPHPRODHE was compared to LLPLPRODHE. And finally, FEFEFW2DHE was compared to FEFEFW1DHE. The basic events in each pair were similar in characteristics and they were accordingly mapped to the same HEP adjustment case (i.e. Case 3 or 4 etc.).
- Request For Additional Information September 29, 2009 Page 24 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response HRA-E1-1 Address how Alarm Closed Discussion relative to reliance on EOP, Response and AOP, and alarm response procedures EOP/AOPs are followed given a fire has been added to FPRA given a fire Model Development report to support the conclusion that credited FPRA actions are consistent with the expected plant response to a fire event including the decision to man the SSF.
IEPRA-1 Resolve issues from gap Closed Appendix D to PRA Quality Self assessment of the ONS Assessment addresses ONS PRA PRA revision 3a technical adequacy for NFPA 805. Open S/Rs with potential impact on quantification of delta risk for change evaluations have been addressed in sensitivity analysis within NFPA 805 Fire PRA Application Calculation.
IEPRA-2 Demonstrate Closed OSC-8863 demonstrates that the ONS convergence for selected PRA CDF results converge at 1 E-09.
truncation limit (FPIE issue)
IGN-A5-1 Use of reactor year/critical Open To be addressed when NUREG/CR-6850 year is updated with the correct numbers based on reactor-year basis; impact is expected to be insignificant. Note that Interim EPRI Report 1019189, which was not used at ONS, would lower ignition frequencies for most bins. Also Bayesian update to
'lower' ignition frequencies was not applied at ONS (only 1 bin was increased). Both measures, if applied, would offset any expectedincrease. This open item is being tracked under PIP G-09-00698 MUD-B4-1 Procedure lacks Closed Per Corrective Action 5 of PIP 0-08-2915, reference to PRA PRA Workplace Procedure XSAA-1 06 was combined standard (draft) revised to reference the Combined PRA standard.
- Request For Additional Information September 29, 2009 Page 25 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response MUD-El-1 Qualify the FRANC Closed Per Corrective Action 6 of PIP 0-08-2915, computer code for use on the FRANC computer code was qualified FPRA as documented in SDQA-30271-NGO.
PP-B2-1 Justification for credit of Closed Partially addressed via multi-compartment non-rated partition analysis; failure to meet SR poses no boundaries insufficient adverse impact on the analysis quality or completeness. Deviation from "enclosed boundary" definition applied to compartment frequency calculation which has no impact on overall CDF/LERF results. Use of zone of influence for defining extent of fire scenario regardless of location of zone boundary ensures that scenario impacts are accurate.
PP-B3-1 Use of open fire zone Closed Partially addressed via multi-compartment boundaries implies credit analysis; failure to meet SR poses no for spatial separation adverse impact on the analysis quality or completeness (see disposition for PP-B2-1).
PP-C3-1 Improve general Closed Partially addressed via multi-compartment description and analysis (see PP-B2-1); failure to meet SR identification of unique FP poses no adverse impact on the analysis features quality or completeness.
PRM-B1-1 Impact of FPIE peer Closed See IEPRA-1.
review open items on FPRA not addressed PRM-D1-1 Circa 2005 fire structure Closed Eliminated reliance on initiators in FPIE model not peer %TBOFIRE and %CSFIRE from pre-reviewed existing fire structure in FPRA.
QLS-A3-1 Discussion in Partitioning Closed No impact on quantification; updated
& Ignition Frequency calc calculation to provide justification for implied that actions exclusion for the 4 structures to reflect that pertaining to 4 structures no further action was necessary for these that were excluded from structures based on the multi-ignition source counting compartment analysis.
had not been completed.
- Request For Additional Information September 29, 2009 Page 26 of 29 Table 4-1 ONS Fire PRA NRC Review - Findings SR Topic Status Response SF-A2-1 Conduct assessment of Open No impact on quantification of FPRA or the potential for diversion Change Evaluations (seismic-fire of suppression flow interaction is purely qualitative per NUREG/CR-6850). See qualitative discussion of seismic fires in the Oconee Unit 3 Fire PRA Summary. PIP G 00698 will track the resolution of this open item.
SF-A4-1 Plant seismic response Open No impact on quantification of FPRA or procedures do not cover Change Evaluations (seismic-fire seismically induced fire interaction is purely qualitative per NUREG/CR-6850). See qualitative discussion of seismic fires in the Oconee Unit 3 Fire PRA Summary Report. PIP G-09-00698 will track the resolution of this open item.
SF-A5-1 Assessment of Open No impact on quantification of FPRA or earthquake impact on fire Change Evaluations (seismic-fire brigade not documented interaction is purely qualitative per NUREG/CR-6850). See qualitative discussion of seismic fires in the Oconee Unit 3 Fire PRA Summary Report. PIP G-09-00698 will track the resolution of this open item.
UNC-A1-1 Uncertainty and sensitivity Closed Uncertainty & Sensitivity Matrix added as analysis incomplete (not Appendix D to FPRA Summary Report; reviewed) sensitivity quantitatively addressed in NFPA 805 FPRA Application Calculation.
Most of the findings from the NRC review have either been addressed or deemed to have no impact on FPRA quantification. As required, a corrective action was generated to track completion of the open items. These items either relate to documentation deficiencies or final resolution of technical issues that are not expected to have a significant impact on the FPRA (i.e., breaker coordination).
- Request For Additional Information September 29, 2009 Page 27 of 29 RAI 6-1:
Provide a detailed overview of the monitoring program that will be used to assess acceptable levels of availability, reliability, and performance of fire protection systems and features. In the response, 1) identify the fire protection systems and features, and the attributes of those systems and features that will be monitored, 2) identify the criteria used to assess the acceptable level of availability, reliability, and performance for each attribute, 3) identify the methods used to monitor availability, reliability, and performance, and 4) describe how unacceptable levels of availability, reliability, and performance will be managed.
Section 2.6 of NFPA 805 requires licensees to establish and monitor acceptable levels of availability, reliability, and performance of fire protection systems and features. While a brief description of how the monitoring program will be developed is provided in Section 4.6 of the TR, insufficient detail is provided for the NRC to make an assessment of the adequacy of the program.
RAI 6-1 RESPONSE:
An overview of the status of the Monitoring program is being provided in response to this RAI to supplement. the information previously provided in the LAR.
The Monitoring Program will be implemented after the LAR submittal as part of the fire protection program transition to NFPA 805. In order to assess the impact of the transition to NFPA 805 on the current monitoring program, the Duke fire protection program documentation hierarchy, maintenance program process/procedures and plant change processes will be reviewed. Sections 4.5.3 and 5.2 of the NEI 04-02 Implementing Guidance will be used during the review process, and that process is described below. The intent of the monitoring transition effort will be to confirm (or modify as necessary) the adequacy of the existing surveillance, testing, maintenance, compensatory measures, and oversight processes for'transition to NFPA 805. This review will consider the following:
- 1. The adequacy of the scope of systems and equipment within existing plant programs (i.e., are the necessary fire protection program systems and features included).
- 2. The performance criteria for the availability and reliability of fire protection systems and features relied on to demonstrate compliance.
- 3. The adequacy of the plant corrective action program in determining causes of equipment and programmatic failures and in minimizing their recurrence.
A Project Instruction for the monitoring program is being developed mirroring the process described in NUMARC 93-01, Industry Guideline For Monitoring the Effectiveness of Maintenance at Nuclear Power Plants. The Project Instruction will be converted to a Duke procedure to support program implementation' 'As currently drafted, the Project Instruction encompasses the NSCA systems and components and Fire Protection systems and features (barriers, specific suppression/detection systems) credited in the B-3 Table and Fire PRA.
- Request For Additional Information September 29, 2009 Page 28 of 29
/
An expert panel will be convened to ensure the following:
- Determine the scope of SSCs and programmatic elements to monitor.
- Establish levels of availability, reliability, or other criteria for those elements that require monitoring.
The four main phases of monitoring process are described below:
- Phase 1- Scoping
" Phase 2- Establishing Risk Criteria
- Phase 3- Risk Determination
- Phase 4- Monitoring Implementation Phase I - Scoping Phase 1 of the process will determine the scope of the NFPA 805 monitoring program. In order to meet the NFPA 805 requirements for monitoring, three basic categories are established:
- Monitoring of Fire Protection Program Structures, Systems, and Components o FP systems credited in NFPA 805 o Additional FP systems and features included in the FPRA
" Monitoring of Fire Protection Programmatic Elements
- Monitoring of Key Assumptions in Engineering Analyses NSCA equipment is generally monitored by the Maintenance Rule. A confirmatory review will be performed to ensure that NSCA SSC's are monitored in the Maintenance rule program and are therefore not expected to be included as part of NFPA 805 Monitoring. It is anticipated that in most cases, for the NSCA type components, the existing Maintenance Rule performance goals will be bounding and that additional NFPA 805 performance goals will not be required.
Phase 2 - Establishing Risk Criteria Phase 2 of the process will establish risk significant criteria for SSCs and programmatic elements within the NFPA 805 monitoring scope. The Fire PRA is the primary tool used to establish risk significant criteria. Only certain SSCs/fire protection program elements are amenable to risk measurement in Fire PRA. Another aspect of risk criteria is establishing performance criteria. These performance criteria will be established for items within the NFPA 805 monitoring scope, regardless of their ability to be measured using risk significant criteria.
The performance criteria used should be availability, reliability, or condition monitoring, as appropriate.
- Request For Additional Information September 29, 2009 Page 29 of 29 Phase 3 - Risk Determination Phase 3 will consist of utilizing the Fire PRA, or other processes, as appropriate, to determine the risk significant SSCs/fire protection program elements using the criteria established in Phase 2.
Phase 4 - Monitoring Implementation Phase 4 is the full implementation of the monitoring program, once the scope and criteria are established in previous phases. The implementation includes the assessment of performance against the established criteria. Follow on steps include refinement of performance goals and criteria, analysis of situations where goals are not met, and addressing items appropriately via the corrective action program.
The data is expected to be captured in databases similar to those used for the Maintenance Rule and the existing processes for Corrective Action Program (PIP) review of equipment failures will be used to review against the newly created NFPA 805 functions and performance goals. The Administrative Control aspects of the Fire Prevention Program are already monitored through the Engineering Programs health reporting process as described in Duke engineering procedure EDM 201. The Project Instruction will be posted to the SharePoint site once it is approved.
ATTACHMENT 1 REGULATORY COMMITMENTS
Attachment 1 Regulatory Commitments The following table identifies regulatory commitments. Any other statements in this submittal represent intended or planned actions. They are provided for information purposes and are not considered to be regulatory commitments.
Commitment Due Date Revise the Transition Report submitted October 31, 2008 to reflect January 31, 2010 the following (RAI 3-1):
Rewrite of Attachment A, Table B-1 to include the following:
- Enhanced wording for clarity where prior approval is cited and modifications are referenced. Clarification will be provided where modifications for compliance are referenced in order to clearly indicate what modifications will occur. (RAI 2-2)
- Include the code years evaluated. (RAI 2-4)
- A review of all areas with suspended ceilings will be performed and wiring, if present, dispositioned. (RAI 2-5)
- The reference to the propane tank and its orientation will be removed. (RAI 2-5)
" All 'Further Actions Required' statements will be reviewed to ensure that those actions that are required to demonstrate compliance are retained as include in LAR 'Yes' and include the commitment in the LAR. Where necessary the compliance statement and compliance basis sections will be updated.
(RAI 2-5)
Attachment C, B-3 Table will be reviewed and updated accordingly to clarify the lack of suppression in a III.G.3 area. (RAI 2-3)
Attachment G - Operator Manual Actions will be revised as follows:
- The term challenging active fire was used incorrectly. It should have stated ... "Embedded in the compliance strategy is the assumption that the 10 minute time frame does not start until confirmation of an active fire." (RAI 3-1)
- A revised list of recovery actions for each fire area will also be included. The completion date for this document is also contingent upon the pending outcome of FAQ 07-30 and its impact on change evaluations, recovery actions, and required plant modifications. (RAI 3-10)
Attachment J - EEEE Transition will be revised to remove all engineering evaluations currently listed. The engineering 1
Commitment Due Date Due Date evaluations currently listed Commitment in Attachment J are allowed and do not need to be submitted in the LAR for NRC approval. (RAI 2-6)
Attachment L will be revised to reflect completion of the NFPA code compliance reviews. (RAI 2-4)
Attachment P will be deleted, along with reference to P-2.
(RAI 2-4)
Attachment S will be revised to reflect correct modifications.
Attachment T will be revised as follows:
" Prior Approval Clarification Request 2 will be revised to eliminate BOP fire area and discuss the new fire areas (AB and TB. (RAI 2-3)
- To request that the NRC formally document as a "prior approval" recognition that within the first 10 minutes following the identification of a confirmed active fire, fire growth will not reach a point where fire damage will (RAI 3-1):
" Result in spurious equipment operation
" Result in a loss of offsite power condition
- Preclude operation of plant equipment from the control room Attachment U will be revised to remove references to DA-Al a and HR-Al. (RAI 5-10).
Implement modifications to address spurious operation of the RCS U2EOC25 - fall 2011 vent valves (Attachment 2) U3EOC26 - spring 2012 U1EOC27 - fall 2012 Complete breaker coordination study (RAI 3-3) June 30, 2010 Implement modifications to address RCPs spurious start and ability January 31, 2010 to ensure pump trip - Scoping is not complete. (Attachment 2)
Implement modifications to address HPI pump spurious start and January 31, 2010 ability to ensure pump trip - Scoping is not complete. (Attachment 2)
Response to RAIs 5-15 and 5-16 January 31, 2010 Complete code compliance reviews and identify required January 31, 2010 modifications in Attachment S. (RAI 2-4)
IN 92-18, "Potential for Loss of Remote Shutdown Capability January 31, 2010 During a Control Room Fire," Study results (RAI 1-1)
Finalize preliminary answer to RAI 5-5. January 31, 2010 2
Commitment Due Date Finalize preliminary answer to RAI 1-2 when resolution of January 31, 2010 outstanding issues for self approval have been resolved. This issue is being addressed as part of the NRC/industry pilot process and is affected by the outcome of FAQ 07-30.
3