RC-13-0054, License Amendment Request - LAR-06-00055 - License Amendment Request to Adopt NFPA 805 Additional Information Regarding Response to Request for Additional Information: Difference between revisions
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{{#Wiki_filter:Thomas D. Gatlin Vice President, Nuclear Operations 803.345.4342 A SCANA COMPANY April 1, 2013 RC-13-0054 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001 Attn: E. A. Brown | {{#Wiki_filter:Thomas D. Gatlin Vice President,Nuclear Operations 803.345.4342 A SCANA COMPANY April 1, 2013 RC-13-0054 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001 Attn: E. A. Brown | ||
==Dear Sir / Madam:== | ==Dear Sir / Madam:== | ||
==Subject:== | ==Subject:== | ||
VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSE AMENDMENT REQUEST -LAR-06-00055 LICENSE AMENDMENT REQUEST TO ADOPT NFPA 805 ADDITIONAL INFORMATION REGARDING RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION | VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSE AMENDMENT REQUEST - LAR-06-00055 LICENSE AMENDMENT REQUEST TO ADOPT NFPA 805 ADDITIONAL INFORMATION REGARDING RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION | ||
==References:== | ==References:== | ||
: 1. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated November 15, 2011, License Amendment Request -LAR-06-00055,"License Amendment Request to Adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants (2001 Edition)" 2. NRC Letter from Robert E. Martin to Thomas D. Gatlin dated July 26, 2012,"Virgil C. Summer Nuclear Station Unit 1 (VCSNS) -Request for Additional Information (TAC NO. ME7586)" ADAMS Accession No. ML12202A027 | : 1. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated November 15, 2011, License Amendment Request - LAR-06-00055, "License Amendment Request to Adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants (2001 Edition)" | ||
: 3. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated October 10, 2012, License Amendment Request -LAR-06-00055, "License Amendment Request to Adopt NFPA 805 Response to Request for Additional Information" 4. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated February 1, 2013, License Amendment Request -LAR-06-00055,License Amendment Request to Adopt NFPA 805 Additional Information Regarding Response to Request for Additional Information" South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority, has identified additional information that will further explain the responses to Probability Risk Assessment (PRA) Request for Additional Information (RAI)Numbers 07, 09, 66, and 68.Virgil C. Summer Station - | : 2. NRC Letter from Robert E. Martin to Thomas D. Gatlin dated July 26, 2012, "Virgil C. Summer Nuclear Station Unit 1 (VCSNS) - Request for Additional Information (TAC NO. ME7586)" ADAMS Accession No. ML12202A027 | ||
* Jenkinsville, SC | : 3. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated October 10, 2012, License Amendment Request - LAR-06-00055, "License Amendment Request to Adopt NFPA 805 Response to Request for Additional Information" | ||
* 29065 | : 4. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated February 1, 2013, License Amendment Request - LAR-06-00055,License Amendment Request to Adopt NFPA 805 Additional Information Regarding Response to Request for Additional Information" South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority, has identified additional information that will further explain the responses to Probability Risk Assessment (PRA) Request for Additional Information (RAI) | ||
* F (803) 345-5209 VIP Document Control Desk CR-06-00055 RC-13-0054 Page 2 of 2 The additional information is being provided as a result of a February 25, 2013 teleconference regarding References 3 and 4. The attachment to this letter provides the additional information. | Numbers 07, 09, 66, and 68. | ||
Virgil C.Summer Station -PostOffice Box 88 | |||
* Jenkinsville, SC *29065 | |||
* F(803) 345-5209 VIP | |||
Document Control Desk CR-06-00055 RC-13-0054 Page 2 of 2 The additional information is being provided as a result of a February 25, 2013 teleconference regarding References 3 and 4. The attachment to this letter provides the additional information. | |||
This letter contains two new regulatory commitments, as outlined in Attachment I1: Increase the scope of circuit protection modifications and Update Generic Methodology Calculation, DC078OB-001. | This letter contains two new regulatory commitments, as outlined in Attachment I1: Increase the scope of circuit protection modifications and Update Generic Methodology Calculation, DC078OB-001. | ||
If you have any questions regarding this submittal, please contact Mr. Bruce L. Thompson at (803) 931-5042.I certify under penalty of perjury that the foregoing is correct and true.E,~ecuted on Thomas D. Gatlin TSFTDG/wm Attachment I: Probability Risk Assessment Additional Information Attachment I1: List of Regulatory Commitments c: K. B. Marsh S. A. Byrne J. B. Archie N. S. Cams J. H. Hamilton J. W. Williams W. M. Cherry V. M. McCree E. A. Brown NRC Resident Inspector S. E. Jenkins Paulette Ledbetter K. M. Sutton NSRC RTS (CR-06-00055) | If you have any questions regarding this submittal, please contact Mr. Bruce L. Thompson at (803) 931-5042. | ||
File (813.20)PRSF (RC-13-0054) | I certify under penalty of perjury that the foregoing is correct and true. | ||
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 1 of 32 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT I PROBABILITY RISK ASSESSMENT ADDITIONAL INFORMATION Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 2 of 32 PRA RAI 07 Section 10 of NUREGICR-6850 Supplement I states that a sensitivity analysis should be performed when using the fire ignition frequencies in the Supplement instead of the fire ignition frequencies | E,~ecuted on Thomas D. Gatlin TSFTDG/wm Attachment I: Probability Risk Assessment Additional Information Attachment I1: List of Regulatory Commitments c: K. B. Marsh S. A. Byrne J. B. Archie N. S. Cams J. H. Hamilton J. W. Williams W. M. Cherry V. M. McCree E. A. Brown NRC Resident Inspector S. E. Jenkins Paulette Ledbetter K. M. Sutton NSRC RTS (CR-06-00055) | ||
Provide the sensitivity analysis of the impact on using the Supplement I frequencies instead of the Table 6-1 frequencies on CDF, LERF, ACDF, and ALERF for all of those bins that are characterized by an alpha that is less than or equal to one. If the sensitivity analysis indicates that the change in risk | File (813.20) | ||
SCE&G Response The VCSNS Fire PRA uses the ignition frequencies (IGF) from the latest guidance related to fire PRAs as given in Supplement 1 to NUREG/CR-6850. | PRSF (RC-13-0054) | ||
Supplement 1 to NUREG/CR-6850 (Section 10.2) addresses the use of the ignition frequencies therein as follows: "The NRC accepts use of these revised fire bin ignition frequencies for fire PRAs conducted for NFPA-805 transition for best-/point-estimate calculations of fire risk (core damage frequency[CDF] and large early release frequency | |||
[LERF]), including delta-risk values from plant change evaluations, with the following provision. | Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 1 of 32 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT I PROBABILITY RISK ASSESSMENT ADDITIONAL INFORMATION | ||
The fire PRA, including plant change evaluations, must also evaluate the sensitivity of the risk and delta-risk results to evaluations performed using the current fire bin ignition frequencies in EPRI 1011989, NUREG/CR-6850, Chapter 6,"Fire Ignition Frequencies," Table 6-1, "Fire Frequency Bins and Generic Frequencies," and Appendix C, "Determination of Generic Fire Frequencies," Table C-3, "Generic Fire Ignition Frequency Model for U.S. Nuclear Power Plants." For those cases where the results from this sensitivity analysis indicate a change in the potential risk significance associated with elements of the fire PRA or plant change evaluations that affects the decisions being made (e.g., what is acceptable with the new frequencies from EPRI 1016735 might not be acceptable with the current applicable set from EPRI 1011989, NUREG/CR-6850), the licensee must address this situation by considering fire protection, or related, measures that can be taken to provide additional defense in-depth." With respect to the required sensitivity analysis, a footnote provides the following clarification: "The sensitivity analyses should be performed for a fire ignition frequency bin using the mean of the fire ignition frequency bins contained in NUREG/CR-6850. | |||
Furthermore, sensitivity analyses only need to be performed for those bins characterized by an alpha from the EPRI 1016735 analysis that is less than or equal to 1. Note that an alpha value less than or equal to 1 is characteristic of a reverse-J shaped probability density function, i.e., the same shape as the non-informative prior distributions used in EPRI 1016735. This reverse-J shape is indicative of the large uncertainty in the bin fire frequency due to the sparsity of data for that bin, and therefore, the potential for significant changes should the post-2000 fire event data differ significantly from the 1991-2000 data. The required sensitivity analysis is, for the purpose of this interim solution, judged to provide an adequate indication of the effects on risk and delta-risk in such a case." | Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 2 of 32 PRA RAI 07 Section 10 of NUREGICR-6850 Supplement I states that a sensitivity analysis should be performed when using the fire ignition frequencies in the Supplement instead of the fire ignition frequencies providedin Table 6-1 of NUREGICR-6850. Provide the sensitivity analysis of the impact on using the Supplement I frequencies instead of the Table 6-1 frequencies on CDF, LERF, ACDF, and ALERF for all of those bins that are characterized by an alpha that is less than or equal to one. If the sensitivity analysis indicates that the change in risk acceptanceguidelines would be exceeded using the values in Table 6-1, justify not meeting the guidelines. | ||
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 3 of 32 Results of the Sensitivity Analysis: Note that SCE&G has revised the license amendment request (LAR) baseline model to correct errors in the main control board (MCB) conditional core damage probabilities (CCDPs) (see PRA RAI 66 for details), delete Control Power Transformer (CPT) credit (see PRA RAI 09 for details), and reflect increased scope of circuit protection modifications (see PRA RAI 66 for details). | SCE&G Response The VCSNS Fire PRA uses the ignition frequencies (IGF) from the latest guidance related to fire PRAs as given in Supplement 1 to NUREG/CR-6850. Supplement 1 to NUREG/CR-6850 (Section 10.2) addresses the use of the ignition frequencies therein as follows: | ||
The results of the sensitivity study for ignition frequency bins with alpha values less than or equal to one are shown in the following table.K ACDF | "The NRC accepts use of these revised fire bin ignition frequencies for fire PRAs conducted for NFPA-805 transition for best-/point-estimate calculations of fire risk (core damage frequency | ||
LERF from from Compliant | [CDF] and large early release frequency [LERF]), including delta-risk values from plant change evaluations, with the following provision. The fire PRA, including plant change evaluations, must also evaluate the sensitivity of the risk and delta-risk results to evaluations performed using the current fire bin ignition frequencies in EPRI 1011989, NUREG/CR-6850, Chapter 6, "Fire Ignition Frequencies," Table 6-1, "Fire Frequency Bins and Generic Frequencies," and Appendix C, "Determination of Generic Fire Frequencies," Table C-3, "Generic Fire Ignition Frequency Model for U.S. Nuclear Power Plants." For those cases where the results from this sensitivity analysis indicate a change in the potential risk significance associated with elements of the fire PRA or plant change evaluations that affects the decisions being made (e.g., what is acceptable with the new frequencies from EPRI 1016735 might not be acceptable with the current applicable set from EPRI 1011989, NUREG/CR-6850), the licensee must address this situation by considering fire protection, or related, measures that can be taken to provide additional defense in-depth." | ||
:Compliant Compliant Co-pliant Revised Baseline 5.9E-05 3.OE-06 7.OE-07 4.3E-09 Plant Sensitivity Case Plant (ie: Revised 1.1E-04 3.8E-06 8.OE-07 1.6E-06 5.3E-09 1.OE-09 Baseline with Updated IGFs)Note for table above: The CDF and LERF given above are associated with fire initiating events but are reasonable proxies for the total plant risk. This is due to the fact that the other hazards for which CDF and LERF estimates are currently available (internal events at power (including internal floods), respectively equal to 4.36E-06/yr and 1.04E-07/yr) represent less than 10 percent of the fire-induced CDF and LERF in the sensitivity case.The combination CDF and Delta CDF using the NUREG/CR-6850 ignition frequencies exceeds the risk acceptance guidelines illustrated for Region II and III of Figure 4 in Regulatory Guide 1.174. Both the LERF and Delta LERF values are within Region III of Figure 5 in Regulatory Guide 1.174.For the plant CDF, approximately 80% of the contribution to the increase is from the main control board scenarios in CB17.01 for sequences involving consequential LOCAs. A source of conservatism in both the base case Fire PRA and the sensitivity case influencing these results is the use of NUREG/CR-6850 Figure L-1 probabilities for unqualified cables. A review of the cable routing system suggests that the cables inside the main control board are mostly qualified and non-Kerite. | With respect to the required sensitivity analysis, a footnote provides the following clarification: | ||
Using the qualified cable curve in Figure L-1 of NUREG/CR-6850 would result in a CDF reduction of a factor of two to three depending on the distance. | "The sensitivity analyses should be performed for a fire ignition frequency bin using the mean of the fire ignition frequency bins contained in NUREG/CR-6850. Furthermore, sensitivity analyses only need to be performed for those bins characterized by an alpha from the EPRI 1016735 analysis that is less than or equal to 1. Note that an alpha value less than or equal to 1 is characteristic of a reverse-J shaped probability density function, i.e., the same shape as the non-informative prior distributions used in EPRI 1016735. This reverse-J shape is indicative of the large uncertainty in the bin fire frequency due to the sparsity of data for that bin, and therefore, the potential for significant changes should the post-2000 fire event data differ significantly from the 1991-2000 data. The required sensitivity analysis is, for the purpose of this interim solution, judged to provide an adequate indication of the effects on risk and delta-risk in such a case." | ||
Consequently, a CDF reduction due to the contribution of main control board fires considering qualified cable would place the combination of CDF and Delta CDF in Region II of Figure 4 in Regulatory Guide 1.174.In addition to this conservatism in the results for fire area C017.01, consistent with the guidance in Section 10.2 of Supplement 1 to NUREG/CR-6850, VCSNS has identified fire protection and related measures that provide additional defense-in-depth (DID) in CB17.01, as justification for the sensitivity analysis results not meeting the acceptance guidelines. | |||
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 4 of 32 VCSNS has governing procedures in place for fire protection activities involving control of temporary storage areas and control of hot work. These procedures are not credited explicitly in the Fire PRA (i.e., the Fire PRA does not include failure probabilities to follow the requirements of these procedures) for postulating transient fires within a Fire Area. The procedures are considered in the Fire PRA consistent with the guidelines in NUREG/CR-6850 for selecting the appropriate credit for prompt suppression and hot work manual suppression curve for the appropriate scenarios and for determining the influence factors serving as weighting factors for transient fire ignition frequencies. | Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 3 of 32 Results of the Sensitivity Analysis: | ||
Consequently, the specific provisions of these procedures are credited for DID for: (1) controlling transient combustibles throughout the plant; and (2)assigning compensatory measures to maintenance activities that may temporarily change the plant configuration. | Note that SCE&G has revised the license amendment request (LAR) baseline model to correct errors in the main control board (MCB) conditional core damage probabilities (CCDPs) (see PRA RAI 66 for details), delete Control Power Transformer (CPT) credit (see PRA RAI 09 for details), and reflect increased scope of circuit protection modifications (see PRA RAI 66 for details). The results of the sensitivity study for ignition frequency bins with alpha values less than or equal to one are shown in the following table. | ||
PRA RAI 09 It was recently stated at the industry fire forum that the Phenomena Identification and Ranking Table Panel (PIRT) being conducted for the circuit failure tests from the DESIREE-FIRE and CAROL-FIRE tests may be eliminating the credit for Control Power Transformers (CPTs) (about a factor 2 reduction) currently allowed by Tables 10-1 and 10-3 of NUREG/CR-6850, Vol. 2, as being invalid when estimating circuit failure probabilities. | K CDF ACDF frm -~ AERF -7AALERF | ||
;CA~LERFn irCDFfrom. LERF from from Compliant :Compliant Compliant Co-pliant Revised Baseline 5.9E-05 3.OE-06 7.OE-07 4.3E-09 Plant Sensitivity Case Plant (ie: Revised 1.1E-04 3.8E-06 8.OE-07 1.6E-06 5.3E-09 1.OE-09 Baseline with Updated IGFs) | |||
Note for table above: The CDF and LERF given above are associated with fire initiating events but are reasonable proxies for the total plant risk. This is due to the fact that the other hazards for which CDF and LERF estimates are currently available (internal events at power (including internal floods), respectively equal to 4.36E-06/yr and 1.04E-07/yr) represent less than 10 percent of the fire-induced CDF and LERF in the sensitivity case. | |||
The combination CDF and Delta CDF using the NUREG/CR-6850 ignition frequencies exceeds the risk acceptance guidelines illustrated for Region II and III of Figure 4 in Regulatory Guide 1.174. Both the LERF and Delta LERF values are within Region III of Figure 5 in Regulatory Guide 1.174. | |||
For the plant CDF, approximately 80% of the contribution to the increase is from the main control board scenarios in CB17.01 for sequences involving consequential LOCAs. A source of conservatism in both the base case Fire PRA and the sensitivity case influencing these results is the use of NUREG/CR-6850 Figure L-1 probabilities for unqualified cables. A review of the cable routing system suggests that the cables inside the main control board are mostly qualified and non-Kerite. Using the qualified cable curve in Figure L-1 of NUREG/CR-6850 would result in a CDF reduction of a factor of two to three depending on the distance. Consequently, a CDF reduction due to the contribution of main control board fires considering qualified cable would place the combination of CDF and Delta CDF in Region II of Figure 4 in Regulatory Guide 1.174. | |||
In addition to this conservatism in the results for fire area C017.01, consistent with the guidance in Section 10.2 of Supplement 1 to NUREG/CR-6850, VCSNS has identified fire protection and related measures that provide additional defense-in-depth (DID) in CB17.01, as justification for the sensitivity analysis results not meeting the acceptance guidelines. | |||
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 4 of 32 VCSNS has governing procedures in place for fire protection activities involving control of temporary storage areas and control of hot work. These procedures are not credited explicitly in the Fire PRA (i.e., the Fire PRA does not include failure probabilities to follow the requirements of these procedures) for postulating transient fires within a Fire Area. The procedures are considered in the Fire PRA consistent with the guidelines in NUREG/CR-6850 for selecting the appropriate credit for prompt suppression and hot work manual suppression curve for the appropriate scenarios and for determining the influence factors serving as weighting factors for transient fire ignition frequencies. Consequently, the specific provisions of these procedures are credited for DID for: (1) controlling transient combustibles throughout the plant; and (2) assigning compensatory measures to maintenance activities that may temporarily change the plant configuration. | |||
PRA RAI 09 It was recently stated at the industry fire forum that the Phenomena Identification and Ranking Table Panel (PIRT) being conducted for the circuit failure tests from the DESIREE-FIRE and CAROL-FIRE tests may be eliminating the credit for Control Power Transformers (CPTs) (about a factor 2 reduction)currently allowed by Tables 10-1 and 10-3 of NUREG/CR-6850, Vol. 2, as being invalid when estimating circuit failure probabilities.Providea sensitivity analysis that removes this CPT credit from the PRA and provide new results that show the impact of this potentialchange on CDF, LERF, ACDF, and ALERF. If the sensitivity analysis indicatesthat the change in risk acceptance guidelines would be exceeded after eliminating CPT credit, pleasejustify not meeting the guidelines. | |||
SCE&G Response In anticipation that the PIRT discussions would result in elimination of the CPT credit, VCSNS has removed CPT credit from the Fire PRA. A sensitivity study was conducted by adding CPT credit back into the model. The impact of this credit on both CDF and LERF, as shown in the following table, is small and not significant. | SCE&G Response In anticipation that the PIRT discussions would result in elimination of the CPT credit, VCSNS has removed CPT credit from the Fire PRA. A sensitivity study was conducted by adding CPT credit back into the model. The impact of this credit on both CDF and LERF, as shown in the following table, is small and not significant. | ||
..ACDFfrom .CDge in ... mALERF, Change in-CDF. ' ACDF from LER!1 | . . ACDFfrom .CDge in . .. mALERF,Change in | ||
It is not clear from the MCR | -CDF.' ACDF from LER!1 fr fr Cipin Compian Compliant,~~li~l Revised Beine 5.8E-05 3.OE-06 7.OE-07 4.3E-09 Baseline Plant Sensitivity Case Plant 5.6E-05 3.OE-06 1.6E-08 5.8E-07 5.7E-09 1.4E-09 (CPT credited) | ||
For example, Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 5 of 32 for | PRA RAI 66 FSS-B2-01: It is not clear from the MCR abandonmentdocument what the criteria are for CR abandonment for MCB fires. Secondly, from the MCB scenarios the conditional core damage probability (CCDP) does not appearcorrect for the specified number of panels as given in Appendix B of the Fire Risk QuantificationTask 14 document. For example, | ||
Provide the | |||
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 5 of 32 for scenarioCB 17.01 MCB 11-10-1, 11-9-1, and 11-8-1, 2, 3, and 4 panels are failed respectively,yet the CCDP from the quantificationdocument specified that the CCDP is largest when only 2 panels are damaged. Also for scenarios CB17.01 MCB 18-18-1, 18 1, 18-16-1, and 18-15-1 the CCDP is the same for each scenario even though 1, 2, 3, and 4 panels are damagedrespectively. Provide the criteriafor CR evacuation for MCB fires, andjustify the CCDPsprovided for the various number of panels damaged. The response should take into account a further examination of the CCDPsfor MCB fires than identified in this question to evaluate if the CCDP problem is more extensive than discussed in this question. Provideupdated CDF, LERF, ACDF, and ALERF values for MCB scenarios. | |||
SCE&G Response The criteria for main control room (MCR) abandonment are discussed in the response to PRA RAI 08.The CCDP issue was an error in the model that was due to the FRANX software treatment of mutually exclusive events. The top logic structure of the fault tree (shown below) includes NOT logic that removes cutsets associated with mutually exclusive events. When the FRANX model sets the failures associated with the fire, it sets all of the failed events to TRUE and then compresses the tree and solves it. If two events are mapped to a scenario that appears in the mutually exclusive logic gate (FIREMEX), the gate @CDFALLF is set to FALSE. This means that only the MCR abandonment logic is considered for the scenario. | SCE&G Response The criteria for main control room (MCR) abandonment are discussed in the response to PRA RAI 08. | ||
This was the root cause of the issue that resulted in abnormal CCDP results for the main control board scenarios. | The CCDP issue was an error in the model that was due to the FRANX software treatment of mutually exclusive events. The top logic structure of the fault tree (shown below) includes NOT logic that removes cutsets associated with mutually exclusive events. When the FRANX model sets the failures associated with the fire, it sets all of the failed events to TRUE and then compresses the tree and solves it. If two events are mapped to a scenario that appears in the mutually exclusive logic gate (FIREMEX), the gate @CDFALLF is set to FALSE. This means that only the MCR abandonment logic is considered for the scenario. This was the root cause of the issue that resulted in abnormal CCDP results for the main control board scenarios. | ||
Correcting this mutually exclusive event treatment resulted in an unacceptable CDF. Another cutset review was conducted which identified additional detailed modeling and increased the scope of circuit protection modifications which reduced the model CDF to approximately'the same value in the LAR. The model has been updated to reflect these changes. In addition, the model has been updated to reflect elimination of CPT credit, and additional transient zone scenarios as discussed in PRA RAI 68. The updated results for the MCB scenarios are listed in the table below including CDF, LERF, ACDF and ALERF. | Correcting this mutually exclusive event treatment resulted in an unacceptable CDF. Another cutset review was conducted which identified additional detailed modeling and increased the scope of circuit protection modifications which reduced the model CDF to approximately'the same value in the LAR. The model has been updated to reflect these changes. In addition, the model has been updated to reflect elimination of CPT credit, and additional transient zone scenarios as discussed in PRA RAI 68. The updated results for the MCB scenarios are listed in the table below including CDF, LERF, ACDF and ALERF. | ||
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 6 of 32 Table 1: Main Control Board Fire Scenarios | |||
-Results LAi/.UIMLb-IU-IU-I b.U41-Ub i.//t-U1 6,)Z:-U/ Note 1 b.bZt-U4 J.it-UV Note i CB17.01_MCB-10-6-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01_MCB-10-7-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-10-8-1 8.21E-07 8.76E-01 7.19E-07 Note 1 1.79E-02 1.47E-08 Note 1 CB17.01 MCB-10-9-1 1.67E-06 9.48E-01 1.59E-06 Note 1 3.26E-02 5.45E-08 Note 1 CB17.01 MCB-1-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-11-10-1 1.67E-06 1.77E-01 2.97E-07 Note 1 6.62E-04 1.11E-09 Note 1 CB17.01 MCB-11-11-1 5.04E-06 2.82E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-11-8-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-11-9-1 8.21E-07 9.48E-01 7.78E-07 Note 1 3.26E-02 2.67E-08 Note 1 CB17.01 MCB-12-10-1 8.21E-07 1.77E-01 1.45E-07 Note 1 6.62E-04 5.43E-10 Note 1 CB17.01_MCB-12-11-1 1.67E-06 2.82E-02 4.71E-08 Note 1 1.19E-05 2.OOE-11 Note 1 CB17.01 MCB-12-12-1 5.04E-06 2.81E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-12-9-1 4.92E-07 9.48E-01 4.66E-07 Note 1 3.26E-02 1.60E-08 Note 1 CB17.01_MCB-13-10-1 4.92E-07 1.77E-01 8.72E-08 Note 1 6.62E-04 3.26E-10 Note 1 CB17.01 MCB-13-11-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-13-12-1 1.67E-06 2.84E-02 4.76E-08 Note 1 1.20E-05 2.02E-11 Note 1 CB17.01 MCB-13-13-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1 Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 7 of 32 1AF 0LER UERýI~CB17.01 MCB-14-11-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01 MCB-14-12-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-14-13-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01 MCB-14-14-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1 CB17.01_MCB-15-12-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01_MCB-15-13-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-15-14-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01_MCB-15-15-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01_MCB-16-13-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-16-14-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-16-15-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01 MCB-16-16-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01 MCB-17-14-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-17-15-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01_MCB-17-16-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01_MCB-17-17-1 5.04E-06 4.82E-03 2.43E-08 Note 1 2.03E-06 1.02E-11 Note 1 CB17.01 MCB-18-15-1 4.92E-07 7.58E-03 3.73E-09 Note 1 3.20E-06 1.57E-12 Note 1 CB17.01 MCB-18-16-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01 MCB-18-17-1 1.67E-06 4.82E-03 8.08E-09 Note 1 2.03E-06 3.40E-12 Note 1 CB17.01 MCB-18-18-1 5.04E-06 4.65E-03 2.34E-08 Note 1 1.96E-06 9.85E-12 Note 1 CB17.01_MCB-2-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-2-2-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-3-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-3-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-3-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-4-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-4-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-5-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-6-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01_MCB-7-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-7-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01 MCB-7-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 8 of 32¶- : Delta,' I | Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 6 of 32 Table 1: Main Control Board Fire Scenarios - Results LAi/.UIMLb-IU-IU-I b.U41-Ub i.//t-U1 6,)Z:-U/ Note 1 b.bZt-U4 J.it-UV Note i CB17.01_MCB-10-6-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01_MCB-10-7-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-10-8-1 8.21E-07 8.76E-01 7.19E-07 Note 1 1.79E-02 1.47E-08 Note 1 CB17.01 MCB-10-9-1 1.67E-06 9.48E-01 1.59E-06 Note 1 3.26E-02 5.45E-08 Note 1 CB17.01 MCB-1-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-11-10-1 1.67E-06 1.77E-01 2.97E-07 Note 1 6.62E-04 1.11E-09 Note 1 CB17.01 MCB-11-11-1 5.04E-06 2.82E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-11-8-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-11-9-1 8.21E-07 9.48E-01 7.78E-07 Note 1 3.26E-02 2.67E-08 Note 1 CB17.01 MCB-12-10-1 8.21E-07 1.77E-01 1.45E-07 Note 1 6.62E-04 5.43E-10 Note 1 CB17.01_MCB-12-11-1 1.67E-06 2.82E-02 4.71E-08 Note 1 1.19E-05 2.OOE-11 Note 1 CB17.01 MCB-12-12-1 5.04E-06 2.81E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-12-9-1 4.92E-07 9.48E-01 4.66E-07 Note 1 3.26E-02 1.60E-08 Note 1 CB17.01_MCB-13-10-1 4.92E-07 1.77E-01 8.72E-08 Note 1 6.62E-04 3.26E-10 Note 1 CB17.01 MCB-13-11-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-13-12-1 1.67E-06 2.84E-02 4.76E-08 Note 1 1.20E-05 2.02E-11 Note 1 CB17.01 MCB-13-13-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1 | ||
~ ~ 'ICCDP CDFCLERP LRF CB17.01 MCB-7-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-7-7-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-8-1-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01 MCB-8-2-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01_MCB-8-3-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-4-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-5-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-6-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01 MCB-8-7-1 1.67E-06 1.07E-01 1.79E-07 Note 1 1.53E-04 2.56E-10 Note 1 CB17.01 MCB-8-8-1 5.04E-06 1.07E-01 5.38E-07 Note 1 1.53E-04 7.69E-10 Note 1 CB17.01_MCB-9-3-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-4-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01 MCB-9-5-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-6-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-7-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-8-1 1.67E-06 8.69E-01 1.45E-06 Note I 1.70E-02 2.85E-08 Note 1 CB17.01 MCB-9-9-1 5.04E-06 9.44E-01. | |||
4.75E-06 Note 1 3.14E-02 1.58E-07 Note 1 Note for Table 1: There are no VFDRs in the MCB scenarios so the baseline and compliant plant MCB scenarios are identical with no delta in CDF or LERF.PRA RAI 68 In the Generic | Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 7 of 32 1AF 0LER UERýI~ | ||
SCE&G Response Transient zone boundaries are conservatively established by using walk down results and qualitative criteria, such as where separation between potential targets exists. The transient ignition source is assumed to be located anywhere within the transient zone boundary, so all targets within the boundary are assumed failed. In response to a peer review comment questioning the adequacy of this strategy when the transient source is located on or near the boundary, a review of the transient fire zone of influence determined that 4 feet was a bounding distance. | CB17.01 MCB-14-11-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01 MCB-14-12-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-14-13-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01 MCB-14-14-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1 CB17.01_MCB-15-12-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01_MCB-15-13-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-15-14-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01_MCB-15-15-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01_MCB-16-13-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-16-14-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-16-15-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01 MCB-16-16-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01 MCB-17-14-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-17-15-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01_MCB-17-16-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01_MCB-17-17-1 5.04E-06 4.82E-03 2.43E-08 Note 1 2.03E-06 1.02E-11 Note 1 CB17.01 MCB-18-15-1 4.92E-07 7.58E-03 3.73E-09 Note 1 3.20E-06 1.57E-12 Note 1 CB17.01 MCB-18-16-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01 MCB-18-17-1 1.67E-06 4.82E-03 8.08E-09 Note 1 2.03E-06 3.40E-12 Note 1 CB17.01 MCB-18-18-1 5.04E-06 4.65E-03 2.34E-08 Note 1 1.96E-06 9.85E-12 Note 1 CB17.01_MCB-2-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-2-2-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-3-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-3-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-3-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-4-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-4-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-5-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-6-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01_MCB-7-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-7-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01 MCB-7-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 | ||
Therefore, the target selection boundary was expanded to include all targets outside, but within 4 feet of, the transient zone boundary.In practice, this results in an overlap in the boundaries of transient zone areas. The resulting overlap ensures that scenarios postulated at or near a boundary would include nearby targets Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 9 of 32 that are actually within a different scenario area. The overlap distance of 4 ft is justified as follows: a. Considering the 98th percentile of a transient fire of approximately 317 kW, a damage criterion for targets of approximately 6 kW/m 2 , and a radiation fraction of 0.3, the radius r of the zone of influence based on flame radiation is estimated, using the methodology in Chapter 5, Section 5.3.1 of NUREG-1805, to be 1.1 m or 3.6 ft.b. When a fixed ignition source is present in the transient zone area, there are two possibilities with regard to its location relative to the boundaries of the scenario area. First, the fixed ignition source may be completely within the boundaries and not near any of them (i.e., at least 4 ft from the boundaries). | |||
In this case, the separation from the boundary, and the fact that the space up to 4 ft from the boundaries has been examined to include nearby targets, bounds any need to assign targets outside the scenario area to fire scenarios that originate in the fixed ignition source. Second, a fixed ignition source may be located on or close to the boundary between adjacent scenario areas. This layout of scenario areas is particularly necessary in electrical rooms where electrical cabinets are targets themselves and must be accounted for in transient fire scenarios postulated on either side of the cabinets. | Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 8 of 32 | ||
In such cases, to capture all appropriate targets in fire scenarios that originate in the fixed ignition source, the fixed ignition source is assigned to all of the applicable adjacent scenario areas.When analyzing the worst case fire scenario in each fire zone, the propagation from the initial ignition source to overhead cable trays is considered. | ¶-: Delta,' Deltag I | ||
As explained in Fire Modeling: | ~ ~Scnari**~~'~' | ||
Generic Methodology, DC0780B-001, the fire propagation model from cable tray to cable tray (35 degree angle vertical propagation profile) as a function of time described in Appendix R of NUREG/CR 6850 is implemented for determining the heat release rate generated by trays in a stack assuming an initial tray is on fire. This model is intended to account for horizontal flame spread in fire durations on the order of the propagation times (i.e., 15 to 20 minutes). | ~ ~ 'ICCDP CDFCLERP LRF CB17.01 MCB-7-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-7-7-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-8-1-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01 MCB-8-2-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01_MCB-8-3-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-4-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-5-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-6-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01 MCB-8-7-1 1.67E-06 1.07E-01 1.79E-07 Note 1 1.53E-04 2.56E-10 Note 1 CB17.01 MCB-8-8-1 5.04E-06 1.07E-01 5.38E-07 Note 1 1.53E-04 7.69E-10 Note 1 CB17.01_MCB-9-3-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-4-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01 MCB-9-5-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-6-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-7-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-8-1 1.67E-06 8.69E-01 1.45E-06 Note I 1.70E-02 2.85E-08 Note 1 CB17.01 MCB-9-9-1 5.04E-06 9.44E-01. 4.75E-06 Note 1 3.14E-02 1.58E-07 Note 1 Note for Table 1: There are no VFDRs in the MCB scenarios so the baseline and compliant plant MCB scenarios are identical with no delta in CDF or LERF. | ||
In responding to this RAI, this method has been expanded so that propagation to adjacent transient zones is included.To account for potential fire propagation beyond the 4-ft overlap and into the neighboring transient zones, additional analysis was performed and is described in the following paragraphs. | PRA RAI 68 In the Generic FireMethodology report, the transientzone describes the zone of damage from the fixed or transientignition source. According to page 12 of 73 of this report,the transientzone bounds the effect of flame spread or propagationsince an extended range of 4 feet beyond the transientzone boundaries was examined for PRA targets.Explain how the transientzone boundary takes into account fire growth over time, or propagation into adjacent transientzones via secondarycombustible fires. Should the finding be that the 4 feet margin does not account adequately for these issues, the PRA should be updated accordingly. | ||
SCE&G Response Transient zone boundaries are conservatively established by using walk down results and qualitative criteria, such as where separation between potential targets exists. The transient ignition source is assumed to be located anywhere within the transient zone boundary, so all targets within the boundary are assumed failed. In response to a peer review comment questioning the adequacy of this strategy when the transient source is located on or near the boundary, a review of the transient fire zone of influence determined that 4 feet was a bounding distance. Therefore, the target selection boundary was expanded to include all targets outside, but within 4 feet of, the transient zone boundary. | |||
In practice, this results in an overlap in the boundaries of transient zone areas. The resulting overlap ensures that scenarios postulated at or near a boundary would include nearby targets | |||
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 9 of 32 that are actually within a different scenario area. The overlap distance of 4 ft is justified as follows: | |||
: a. Considering the 98th percentile of a transient fire of approximately 317 kW, a damage criterion for targets of approximately 6 kW/m 2, and a radiation fraction of 0.3, the radius r of the zone of influence based on flame radiation is estimated, using the methodology in Chapter 5, Section 5.3.1 of NUREG-1805, to be 1.1 m or 3.6 ft. | |||
: b. When a fixed ignition source is present in the transient zone area, there are two possibilities with regard to its location relative to the boundaries of the scenario area. First, the fixed ignition source may be completely within the boundaries and not near any of them (i.e., at least 4 ft from the boundaries). In this case, the separation from the boundary, and the fact that the space up to 4 ft from the boundaries has been examined to include nearby targets, bounds any need to assign targets outside the scenario area to fire scenarios that originate in the fixed ignition source. Second, a fixed ignition source may be located on or close to the boundary between adjacent scenario areas. This layout of scenario areas is particularly necessary in electrical rooms where electrical cabinets are targets themselves and must be accounted for in transient fire scenarios postulated on either side of the cabinets. In such cases, to capture all appropriate targets in fire scenarios that originate in the fixed ignition source, the fixed ignition source is assigned to all of the applicable adjacent scenario areas. | |||
When analyzing the worst case fire scenario in each fire zone, the propagation from the initial ignition source to overhead cable trays is considered. As explained in Fire Modeling: Generic Methodology, DC0780B-001, the fire propagation model from cable tray to cable tray (35 degree angle vertical propagation profile) as a function of time described in Appendix R of NUREG/CR 6850 is implemented for determining the heat release rate generated by trays in a stack assuming an initial tray is on fire. This model is intended to account for horizontal flame spread in fire durations on the order of the propagation times (i.e., 15 to 20 minutes). In responding to this RAI, this method has been expanded so that propagation to adjacent transient zones is included. | |||
To account for potential fire propagation beyond the 4-ft overlap and into the neighboring transient zones, additional analysis was performed and is described in the following paragraphs. | |||
Based on walkdowns performed by plant personnel on March 4-6, 2013, and based on the review of drawings for those transient zones unavailable for walkdowns, a list was compiled of transient zones that contain cable trays that extend across the transient zone boundaries, which, if ignited, could result in fire spreading to adjacent transient zones. The results of the walkdowns and drawing review are provided in Table 2. | Based on walkdowns performed by plant personnel on March 4-6, 2013, and based on the review of drawings for those transient zones unavailable for walkdowns, a list was compiled of transient zones that contain cable trays that extend across the transient zone boundaries, which, if ignited, could result in fire spreading to adjacent transient zones. The results of the walkdowns and drawing review are provided in Table 2. | ||
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 10 of 32 Table 2: Walkdown and Drawing Review Results for Potential for Fire Propagation Across Transient Zone Boundaries AB01.04 AB01.04-T1 One (1) cable tray from T1-T2 Walkdown AB301.04 AB101.04-T10 Not Applicable Walkdown AB01.04 AB01.04-T11 Not Applicable D- 214-073 AB01.04 AB01.04-T12 Not Applicable D- 214-073 A1301.04 AB301.04-T13 Not Applicable D- 214-073 AB301.04 ABO1.04-T2 Four (4 | |||
Note 2: One or both of the CCDP values is less than 2E-08, and therefore not a significant risk contributor. | Note 2: One or both of the CCDP values is less than 2E-08, and therefore not a significant risk contributor. | ||
Any other statements in this submittal are provided for information purposes and are not considered to be commitments. | Document Control Desk CR-06-00055 Attachment II RC-13-0054 Page 1 of 1 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT II LIST OF REGULATORY COMMITMENTS The following table identifies those actions committed to by SCE&G, Virgil C. Summer Nuclear Station in this document. Any other statements in this submittal are provided for information purposes and are not considered to be commitments. Please direct questions regarding these commitments to Mr. Bruce L Thompson, Manager, Nuclear Licensing, (803) 931-5042. | ||
Please direct questions regarding these commitments to Mr. Bruce L Thompson, Manager, Nuclear Licensing, (803) 931-5042.TDUE DATE [ EVENT Increase the scope of circuit protection modifications 2015 Update Generic Methodology Calculation, DC0780B-001 July 1, 2013}} | TDUE DATE [ EVENT Increase the scope of circuit protection modifications 2015 Update Generic Methodology Calculation, DC0780B-001 July 1, 2013}} |
Latest revision as of 06:58, 6 February 2020
ML13092A333 | |
Person / Time | |
---|---|
Site: | Summer ![]() |
Issue date: | 04/01/2013 |
From: | Gatlin T South Carolina Electric & Gas Co |
To: | Ellen Brown Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
RC-13-0054 | |
Download: ML13092A333 (35) | |
Text
Thomas D. Gatlin Vice President,Nuclear Operations 803.345.4342 A SCANA COMPANY April 1, 2013 RC-13-0054 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001 Attn: E. A. Brown
Dear Sir / Madam:
Subject:
VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSE AMENDMENT REQUEST - LAR-06-00055 LICENSE AMENDMENT REQUEST TO ADOPT NFPA 805 ADDITIONAL INFORMATION REGARDING RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION
References:
- 1. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated November 15, 2011, License Amendment Request - LAR-06-00055, "License Amendment Request to Adopt NFPA 805 Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants (2001 Edition)"
- 2. NRC Letter from Robert E. Martin to Thomas D. Gatlin dated July 26, 2012, "Virgil C. Summer Nuclear Station Unit 1 (VCSNS) - Request for Additional Information (TAC NO. ME7586)" ADAMS Accession No. ML12202A027
- 3. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated October 10, 2012, License Amendment Request - LAR-06-00055, "License Amendment Request to Adopt NFPA 805 Response to Request for Additional Information"
- 4. Letter from Thomas D. Gatlin to NRC Document Control Desk, dated February 1, 2013, License Amendment Request - LAR-06-00055,License Amendment Request to Adopt NFPA 805 Additional Information Regarding Response to Request for Additional Information" South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority, has identified additional information that will further explain the responses to Probability Risk Assessment (PRA) Request for Additional Information (RAI)
Numbers 07, 09, 66, and 68.
Virgil C.Summer Station -PostOffice Box 88
- Jenkinsville, SC *29065
- F(803) 345-5209 VIP
Document Control Desk CR-06-00055 RC-13-0054 Page 2 of 2 The additional information is being provided as a result of a February 25, 2013 teleconference regarding References 3 and 4. The attachment to this letter provides the additional information.
This letter contains two new regulatory commitments, as outlined in Attachment I1: Increase the scope of circuit protection modifications and Update Generic Methodology Calculation, DC078OB-001.
If you have any questions regarding this submittal, please contact Mr. Bruce L. Thompson at (803) 931-5042.
I certify under penalty of perjury that the foregoing is correct and true.
E,~ecuted on Thomas D. Gatlin TSFTDG/wm Attachment I: Probability Risk Assessment Additional Information Attachment I1: List of Regulatory Commitments c: K. B. Marsh S. A. Byrne J. B. Archie N. S. Cams J. H. Hamilton J. W. Williams W. M. Cherry V. M. McCree E. A. Brown NRC Resident Inspector S. E. Jenkins Paulette Ledbetter K. M. Sutton NSRC RTS (CR-06-00055)
File (813.20)
PRSF (RC-13-0054)
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 1 of 32 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT I PROBABILITY RISK ASSESSMENT ADDITIONAL INFORMATION
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 2 of 32 PRA RAI 07 Section 10 of NUREGICR-6850 Supplement I states that a sensitivity analysis should be performed when using the fire ignition frequencies in the Supplement instead of the fire ignition frequencies providedin Table 6-1 of NUREGICR-6850. Provide the sensitivity analysis of the impact on using the Supplement I frequencies instead of the Table 6-1 frequencies on CDF, LERF, ACDF, and ALERF for all of those bins that are characterized by an alpha that is less than or equal to one. If the sensitivity analysis indicates that the change in risk acceptanceguidelines would be exceeded using the values in Table 6-1, justify not meeting the guidelines.
SCE&G Response The VCSNS Fire PRA uses the ignition frequencies (IGF) from the latest guidance related to fire PRAs as given in Supplement 1 to NUREG/CR-6850. Supplement 1 to NUREG/CR-6850 (Section 10.2) addresses the use of the ignition frequencies therein as follows:
"The NRC accepts use of these revised fire bin ignition frequencies for fire PRAs conducted for NFPA-805 transition for best-/point-estimate calculations of fire risk (core damage frequency
[CDF] and large early release frequency [LERF]), including delta-risk values from plant change evaluations, with the following provision. The fire PRA, including plant change evaluations, must also evaluate the sensitivity of the risk and delta-risk results to evaluations performed using the current fire bin ignition frequencies in EPRI 1011989, NUREG/CR-6850, Chapter 6, "Fire Ignition Frequencies," Table 6-1, "Fire Frequency Bins and Generic Frequencies," and Appendix C, "Determination of Generic Fire Frequencies," Table C-3, "Generic Fire Ignition Frequency Model for U.S. Nuclear Power Plants." For those cases where the results from this sensitivity analysis indicate a change in the potential risk significance associated with elements of the fire PRA or plant change evaluations that affects the decisions being made (e.g., what is acceptable with the new frequencies from EPRI 1016735 might not be acceptable with the current applicable set from EPRI 1011989, NUREG/CR-6850), the licensee must address this situation by considering fire protection, or related, measures that can be taken to provide additional defense in-depth."
With respect to the required sensitivity analysis, a footnote provides the following clarification:
"The sensitivity analyses should be performed for a fire ignition frequency bin using the mean of the fire ignition frequency bins contained in NUREG/CR-6850. Furthermore, sensitivity analyses only need to be performed for those bins characterized by an alpha from the EPRI 1016735 analysis that is less than or equal to 1. Note that an alpha value less than or equal to 1 is characteristic of a reverse-J shaped probability density function, i.e., the same shape as the non-informative prior distributions used in EPRI 1016735. This reverse-J shape is indicative of the large uncertainty in the bin fire frequency due to the sparsity of data for that bin, and therefore, the potential for significant changes should the post-2000 fire event data differ significantly from the 1991-2000 data. The required sensitivity analysis is, for the purpose of this interim solution, judged to provide an adequate indication of the effects on risk and delta-risk in such a case."
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 3 of 32 Results of the Sensitivity Analysis:
Note that SCE&G has revised the license amendment request (LAR) baseline model to correct errors in the main control board (MCB) conditional core damage probabilities (CCDPs) (see PRA RAI 66 for details), delete Control Power Transformer (CPT) credit (see PRA RAI 09 for details), and reflect increased scope of circuit protection modifications (see PRA RAI 66 for details). The results of the sensitivity study for ignition frequency bins with alpha values less than or equal to one are shown in the following table.
K CDF ACDF frm -~ AERF -7AALERF
- CA~LERFn irCDFfrom. LERF from from Compliant
- Compliant Compliant Co-pliant Revised Baseline 5.9E-05 3.OE-06 7.OE-07 4.3E-09 Plant Sensitivity Case Plant (ie: Revised 1.1E-04 3.8E-06 8.OE-07 1.6E-06 5.3E-09 1.OE-09 Baseline with Updated IGFs)
Note for table above: The CDF and LERF given above are associated with fire initiating events but are reasonable proxies for the total plant risk. This is due to the fact that the other hazards for which CDF and LERF estimates are currently available (internal events at power (including internal floods), respectively equal to 4.36E-06/yr and 1.04E-07/yr) represent less than 10 percent of the fire-induced CDF and LERF in the sensitivity case.
The combination CDF and Delta CDF using the NUREG/CR-6850 ignition frequencies exceeds the risk acceptance guidelines illustrated for Region II and III of Figure 4 in Regulatory Guide 1.174. Both the LERF and Delta LERF values are within Region III of Figure 5 in Regulatory Guide 1.174.
For the plant CDF, approximately 80% of the contribution to the increase is from the main control board scenarios in CB17.01 for sequences involving consequential LOCAs. A source of conservatism in both the base case Fire PRA and the sensitivity case influencing these results is the use of NUREG/CR-6850 Figure L-1 probabilities for unqualified cables. A review of the cable routing system suggests that the cables inside the main control board are mostly qualified and non-Kerite. Using the qualified cable curve in Figure L-1 of NUREG/CR-6850 would result in a CDF reduction of a factor of two to three depending on the distance. Consequently, a CDF reduction due to the contribution of main control board fires considering qualified cable would place the combination of CDF and Delta CDF in Region II of Figure 4 in Regulatory Guide 1.174.
In addition to this conservatism in the results for fire area C017.01, consistent with the guidance in Section 10.2 of Supplement 1 to NUREG/CR-6850, VCSNS has identified fire protection and related measures that provide additional defense-in-depth (DID) in CB17.01, as justification for the sensitivity analysis results not meeting the acceptance guidelines.
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 4 of 32 VCSNS has governing procedures in place for fire protection activities involving control of temporary storage areas and control of hot work. These procedures are not credited explicitly in the Fire PRA (i.e., the Fire PRA does not include failure probabilities to follow the requirements of these procedures) for postulating transient fires within a Fire Area. The procedures are considered in the Fire PRA consistent with the guidelines in NUREG/CR-6850 for selecting the appropriate credit for prompt suppression and hot work manual suppression curve for the appropriate scenarios and for determining the influence factors serving as weighting factors for transient fire ignition frequencies. Consequently, the specific provisions of these procedures are credited for DID for: (1) controlling transient combustibles throughout the plant; and (2) assigning compensatory measures to maintenance activities that may temporarily change the plant configuration.
PRA RAI 09 It was recently stated at the industry fire forum that the Phenomena Identification and Ranking Table Panel (PIRT) being conducted for the circuit failure tests from the DESIREE-FIRE and CAROL-FIRE tests may be eliminating the credit for Control Power Transformers (CPTs) (about a factor 2 reduction)currently allowed by Tables 10-1 and 10-3 of NUREG/CR-6850, Vol. 2, as being invalid when estimating circuit failure probabilities.Providea sensitivity analysis that removes this CPT credit from the PRA and provide new results that show the impact of this potentialchange on CDF, LERF, ACDF, and ALERF. If the sensitivity analysis indicatesthat the change in risk acceptance guidelines would be exceeded after eliminating CPT credit, pleasejustify not meeting the guidelines.
SCE&G Response In anticipation that the PIRT discussions would result in elimination of the CPT credit, VCSNS has removed CPT credit from the Fire PRA. A sensitivity study was conducted by adding CPT credit back into the model. The impact of this credit on both CDF and LERF, as shown in the following table, is small and not significant.
. . ACDFfrom .CDge in . .. mALERF,Change in
-CDF.' ACDF from LER!1 fr fr Cipin Compian Compliant,~~li~l Revised Beine 5.8E-05 3.OE-06 7.OE-07 4.3E-09 Baseline Plant Sensitivity Case Plant 5.6E-05 3.OE-06 1.6E-08 5.8E-07 5.7E-09 1.4E-09 (CPT credited)
PRA RAI 66 FSS-B2-01: It is not clear from the MCR abandonmentdocument what the criteria are for CR abandonment for MCB fires. Secondly, from the MCB scenarios the conditional core damage probability (CCDP) does not appearcorrect for the specified number of panels as given in Appendix B of the Fire Risk QuantificationTask 14 document. For example,
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 5 of 32 for scenarioCB 17.01 MCB 11-10-1, 11-9-1, and 11-8-1, 2, 3, and 4 panels are failed respectively,yet the CCDP from the quantificationdocument specified that the CCDP is largest when only 2 panels are damaged. Also for scenarios CB17.01 MCB 18-18-1, 18 1, 18-16-1, and 18-15-1 the CCDP is the same for each scenario even though 1, 2, 3, and 4 panels are damagedrespectively. Provide the criteriafor CR evacuation for MCB fires, andjustify the CCDPsprovided for the various number of panels damaged. The response should take into account a further examination of the CCDPsfor MCB fires than identified in this question to evaluate if the CCDP problem is more extensive than discussed in this question. Provideupdated CDF, LERF, ACDF, and ALERF values for MCB scenarios.
SCE&G Response The criteria for main control room (MCR) abandonment are discussed in the response to PRA RAI 08.
The CCDP issue was an error in the model that was due to the FRANX software treatment of mutually exclusive events. The top logic structure of the fault tree (shown below) includes NOT logic that removes cutsets associated with mutually exclusive events. When the FRANX model sets the failures associated with the fire, it sets all of the failed events to TRUE and then compresses the tree and solves it. If two events are mapped to a scenario that appears in the mutually exclusive logic gate (FIREMEX), the gate @CDFALLF is set to FALSE. This means that only the MCR abandonment logic is considered for the scenario. This was the root cause of the issue that resulted in abnormal CCDP results for the main control board scenarios.
Correcting this mutually exclusive event treatment resulted in an unacceptable CDF. Another cutset review was conducted which identified additional detailed modeling and increased the scope of circuit protection modifications which reduced the model CDF to approximately'the same value in the LAR. The model has been updated to reflect these changes. In addition, the model has been updated to reflect elimination of CPT credit, and additional transient zone scenarios as discussed in PRA RAI 68. The updated results for the MCB scenarios are listed in the table below including CDF, LERF, ACDF and ALERF.
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 6 of 32 Table 1: Main Control Board Fire Scenarios - Results LAi/.UIMLb-IU-IU-I b.U41-Ub i.//t-U1 6,)Z:-U/ Note 1 b.bZt-U4 J.it-UV Note i CB17.01_MCB-10-6-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01_MCB-10-7-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-10-8-1 8.21E-07 8.76E-01 7.19E-07 Note 1 1.79E-02 1.47E-08 Note 1 CB17.01 MCB-10-9-1 1.67E-06 9.48E-01 1.59E-06 Note 1 3.26E-02 5.45E-08 Note 1 CB17.01 MCB-1-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-11-10-1 1.67E-06 1.77E-01 2.97E-07 Note 1 6.62E-04 1.11E-09 Note 1 CB17.01 MCB-11-11-1 5.04E-06 2.82E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-11-8-1 4.92E-07 8.76E-01 4.31E-07 Note 1 1.79E-02 8.80E-09 Note 1 CB17.01 MCB-11-9-1 8.21E-07 9.48E-01 7.78E-07 Note 1 3.26E-02 2.67E-08 Note 1 CB17.01 MCB-12-10-1 8.21E-07 1.77E-01 1.45E-07 Note 1 6.62E-04 5.43E-10 Note 1 CB17.01_MCB-12-11-1 1.67E-06 2.82E-02 4.71E-08 Note 1 1.19E-05 2.OOE-11 Note 1 CB17.01 MCB-12-12-1 5.04E-06 2.81E-02 1.42E-07 Note 1 1.19E-05 6.01E-11 Note 1 CB17.01_MCB-12-9-1 4.92E-07 9.48E-01 4.66E-07 Note 1 3.26E-02 1.60E-08 Note 1 CB17.01_MCB-13-10-1 4.92E-07 1.77E-01 8.72E-08 Note 1 6.62E-04 3.26E-10 Note 1 CB17.01 MCB-13-11-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-13-12-1 1.67E-06 2.84E-02 4.76E-08 Note 1 1.20E-05 2.02E-11 Note 1 CB17.01 MCB-13-13-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 7 of 32 1AF 0LER UERýI~
CB17.01 MCB-14-11-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01 MCB-14-12-1 8.21E-07 2.84E-02 2.33E-08 Note 1 1.20E-05 9.89E-12 Note 1 CB17.01 MCB-14-13-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01 MCB-14-14-1 5.04E-06 8.49E-03 4.27E-08 Note 1 3.58E-06 1.80E-11 Note 1 CB17.01_MCB-15-12-1 4.92E-07 2.84E-02 1.40E-08 Note 1 1.20E-05 5.93E-12 Note 1 CB17.01_MCB-15-13-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-15-14-1 1.67E-06 8.49E-03 1.42E-08 Note 1 3.58E-06 5.99E-12 Note 1 CB17.01_MCB-15-15-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01_MCB-16-13-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-16-14-1 8.21E-07 8.49E-03 6.97E-09 Note 1 3.58E-06 2.94E-12 Note 1 CB17.01_MCB-16-15-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01 MCB-16-16-1 5.04E-06 7.58E-03 3.82E-08 Note 1 3.20E-06 1.61E-11 Note 1 CB17.01 MCB-17-14-1 4.92E-07 8.49E-03 4.18E-09 Note 1 3.58E-06 1.76E-12 Note 1 CB17.01 MCB-17-15-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01_MCB-17-16-1 1.67E-06 7.58E-03 1.27E-08 Note 1 3.20E-06 5.35E-12 Note 1 CB17.01_MCB-17-17-1 5.04E-06 4.82E-03 2.43E-08 Note 1 2.03E-06 1.02E-11 Note 1 CB17.01 MCB-18-15-1 4.92E-07 7.58E-03 3.73E-09 Note 1 3.20E-06 1.57E-12 Note 1 CB17.01 MCB-18-16-1 8.21E-07 7.58E-03 6.22E-09 Note 1 3.20E-06 2.62E-12 Note 1 CB17.01 MCB-18-17-1 1.67E-06 4.82E-03 8.08E-09 Note 1 2.03E-06 3.40E-12 Note 1 CB17.01 MCB-18-18-1 5.04E-06 4.65E-03 2.34E-08 Note 1 1.96E-06 9.85E-12 Note 1 CB17.01_MCB-2-1-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-2-2-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-3-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-3-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-3-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-4-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01_MCB-4-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-4-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-1-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-2-1 1.67E-06 4.67E-03 7.82E-09 Note 1 1.97E-06 3.29E-12 Note 1 CB17.01 MCB-5-3-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-4-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01 MCB-5-5-1 5.04E-06 4.67E-03 2.35E-08 Note 1 1.97E-06 9.90E-12 Note 1 CB17.01_MCB-6-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01 MCB-6-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-6-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01_MCB-7-1-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-2-1 8.21E-07 1.04E-01 8.56E-08 Note 1 4.41E-05 3.62E-11 Note 1 CB17.01_MCB-7-3-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01_MCB-7-4-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1 CB17.01 MCB-7-5-1 1.67E-06 1.04E-01 1.74E-07 Note 1 4.41E-05 7.38E-11 Note 1
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 8 of 32
¶-: Delta,' Deltag I
~ ~Scnari**~~'~'
~ ~ 'ICCDP CDFCLERP LRF CB17.01 MCB-7-6-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-7-7-1 5.04E-06 1.04E-01 5.25E-07 Note 1 4.41E-05 2.22E-10 Note 1 CB17.01 MCB-8-1-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01 MCB-8-2-1 4.92E-07 1.07E-01 5.25E-08 Note 1 1.53E-04 7.51E-11 Note 1 CB17.01_MCB-8-3-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-4-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-5-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01_MCB-8-6-1 8.21E-07 1.07E-01 8.77E-08 Note 1 1.53E-04 1.25E-10 Note 1 CB17.01 MCB-8-7-1 1.67E-06 1.07E-01 1.79E-07 Note 1 1.53E-04 2.56E-10 Note 1 CB17.01 MCB-8-8-1 5.04E-06 1.07E-01 5.38E-07 Note 1 1.53E-04 7.69E-10 Note 1 CB17.01_MCB-9-3-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-4-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01 MCB-9-5-1 4.92E-07 8.69E-01 4.27E-07 Note 1 1.70E-02 8.37E-09 Note 1 CB17.01_MCB-9-6-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-7-1 8.21E-07 8.69E-01 7.13E-07 Note 1 1.70E-02 1.40E-08 Note 1 CB17.01 MCB-9-8-1 1.67E-06 8.69E-01 1.45E-06 Note I 1.70E-02 2.85E-08 Note 1 CB17.01 MCB-9-9-1 5.04E-06 9.44E-01. 4.75E-06 Note 1 3.14E-02 1.58E-07 Note 1 Note for Table 1: There are no VFDRs in the MCB scenarios so the baseline and compliant plant MCB scenarios are identical with no delta in CDF or LERF.
PRA RAI 68 In the Generic FireMethodology report, the transientzone describes the zone of damage from the fixed or transientignition source. According to page 12 of 73 of this report,the transientzone bounds the effect of flame spread or propagationsince an extended range of 4 feet beyond the transientzone boundaries was examined for PRA targets.Explain how the transientzone boundary takes into account fire growth over time, or propagation into adjacent transientzones via secondarycombustible fires. Should the finding be that the 4 feet margin does not account adequately for these issues, the PRA should be updated accordingly.
SCE&G Response Transient zone boundaries are conservatively established by using walk down results and qualitative criteria, such as where separation between potential targets exists. The transient ignition source is assumed to be located anywhere within the transient zone boundary, so all targets within the boundary are assumed failed. In response to a peer review comment questioning the adequacy of this strategy when the transient source is located on or near the boundary, a review of the transient fire zone of influence determined that 4 feet was a bounding distance. Therefore, the target selection boundary was expanded to include all targets outside, but within 4 feet of, the transient zone boundary.
In practice, this results in an overlap in the boundaries of transient zone areas. The resulting overlap ensures that scenarios postulated at or near a boundary would include nearby targets
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 9 of 32 that are actually within a different scenario area. The overlap distance of 4 ft is justified as follows:
- a. Considering the 98th percentile of a transient fire of approximately 317 kW, a damage criterion for targets of approximately 6 kW/m 2, and a radiation fraction of 0.3, the radius r of the zone of influence based on flame radiation is estimated, using the methodology in Chapter 5, Section 5.3.1 of NUREG-1805, to be 1.1 m or 3.6 ft.
- b. When a fixed ignition source is present in the transient zone area, there are two possibilities with regard to its location relative to the boundaries of the scenario area. First, the fixed ignition source may be completely within the boundaries and not near any of them (i.e., at least 4 ft from the boundaries). In this case, the separation from the boundary, and the fact that the space up to 4 ft from the boundaries has been examined to include nearby targets, bounds any need to assign targets outside the scenario area to fire scenarios that originate in the fixed ignition source. Second, a fixed ignition source may be located on or close to the boundary between adjacent scenario areas. This layout of scenario areas is particularly necessary in electrical rooms where electrical cabinets are targets themselves and must be accounted for in transient fire scenarios postulated on either side of the cabinets. In such cases, to capture all appropriate targets in fire scenarios that originate in the fixed ignition source, the fixed ignition source is assigned to all of the applicable adjacent scenario areas.
When analyzing the worst case fire scenario in each fire zone, the propagation from the initial ignition source to overhead cable trays is considered. As explained in Fire Modeling: Generic Methodology, DC0780B-001, the fire propagation model from cable tray to cable tray (35 degree angle vertical propagation profile) as a function of time described in Appendix R of NUREG/CR 6850 is implemented for determining the heat release rate generated by trays in a stack assuming an initial tray is on fire. This model is intended to account for horizontal flame spread in fire durations on the order of the propagation times (i.e., 15 to 20 minutes). In responding to this RAI, this method has been expanded so that propagation to adjacent transient zones is included.
To account for potential fire propagation beyond the 4-ft overlap and into the neighboring transient zones, additional analysis was performed and is described in the following paragraphs.
Based on walkdowns performed by plant personnel on March 4-6, 2013, and based on the review of drawings for those transient zones unavailable for walkdowns, a list was compiled of transient zones that contain cable trays that extend across the transient zone boundaries, which, if ignited, could result in fire spreading to adjacent transient zones. The results of the walkdowns and drawing review are provided in Table 2.
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 10 of 32 Table 2: Walkdown and Drawing Review Results for Potential for Fire Propagation Across Transient Zone Boundaries AB01.04 AB01.04-T1 One (1) cable tray from T1-T2 Walkdown AB301.04 AB101.04-T10 Not Applicable Walkdown AB01.04 AB01.04-T11 Not Applicable D- 214-073 AB01.04 AB01.04-T12 Not Applicable D- 214-073 A1301.04 AB301.04-T13 Not Applicable D- 214-073 AB301.04 ABO1.04-T2 Four (4) Cable trays going from T2-T8 and Two (2) cable trays going from T2-T7 Walkdown ABO1.04 AB101.04-T3 Not Applicable Walkdown ABO1.04 ABO1.04-T4 Not Applicable Walkdown AB301.04 ABO1.04-T5 Not Applicable Walkdown AB301.04 ABO1.04-T6 Not Applicable Walkdown AB301.04 AB101.04-T7 Two (2) cable trays going from T2-T7 and Two Cable trays going from T7-T9 Walkdown AB301.04 ABO1.04-T8 Four (4) Cable Trays going from T2-T8 Walkdown AB301.04 AB101.04-T9 Two (2) cable trays going from T7-T9 Walkdown AB301.08.02 AB101.08.02-T1 At least 3 cable trays going from T2-T1 D-214-074 AB01.08.02 ABO1.08.02-T2 At least 3 cable trays going from T1-T2 D-214-074 AB01.08.02 ABO1.08.02-T3 One (1) cable tray going from T3-T4 D-214-074 AB301.08.02 ABO1.08.02-T4 Two (2) cable trays going from T3-T4 and Two (2) cable tray from T4-T5 D-214-074 AB301.08.02 ABO1.08.02-T5 Two (2) cable tray from T4-T5 D-214-074 AB301.09 AB01.09-T1 Not Applicable D- 214-073 AB301.09 ABO1.09-T2 Not Applicable D- 214-073 AB301.09 AB101.09-T3 Not Applicable D- 214-073 ABO1.09 AB101.09-T4 T3-T4 One cable tray D- 214-073 AB01.10 AB01.10-T1 Not Applicable Walkdown ABO1.10 AB01.10-T10 Not Applicable Walkdown ABO1.10 ABO1 .10-T1 1 Not Applicable Walkdown AB301.10 AB101.10-T12 Not Applicable Walkdown
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 11 of 32
- ..,* , .':*.i,!',*,;.l#*',:';,i*[:[*.k*.i ... . .....................
CJ'mactet4r" Traffnsidbit~Zon . :Sk , WadonOrDrawingý AB01.10 AB01.10-T13 Two (2) Cable Trays from T13-T14 Walkdown AB01.10 AB01.10-T14 Two (2) Cable Trays from T14-T13 Walkdown ABO1.10 AB01.10-T15 One (1) cable tray from T15-T14 Walkdown ABO1.10 AB01.10-T16 Not Applicable Walkdown ABO1.10 AB01.10-T17 Not Applicable D-214-076 ABO1.10 ABO1.10-T2 Not Applicable Walkdown AB301.10 ABO1.10-T3 Not Applicable Walkdown ABO1.10 ABOI.10-T4 Not Applicable Walkdown ABO1.10 ABO1.10-T5 Not Applicable Walkdown AB301.10 ABO1.10-T6 Not Applicable D- 214-077 ABO1.10 ABO1.10-T7 Not Applicable Walkdown ABO1.10 ABO1.10-T8 Not Applicable Walkdown AB01.10 ABO1.10-T9 Not Applicable Walkdown ABO1.17 AB01.17-T1 Not Applicable D- 214-077 ABO1.17 ABO1.17-T2 Not Applicable D- 214-077 ABO1.17 ABO1.17-T3 Not Applicable D- 214-077 ABO1.17 ABO1.17-T4 Not Applicable D- 214-077 ABO1.18.01 AB01.18.01-T1 Cable trays coming from T1-T5 ABO1.18.02 (not applicable: covered by multicompartment Walkdown analysis)
ABO1.18.01 AB01.18.01-T10 Not Applicable Walkdown ABO1.18.01 ABO1.18.01-T11 Not Applicable Walkdown ABO1.18.01 AB01.18.01-T12 Not Applicable Walkdown ABO1.18.01 AB01.18.01-T13 Not Applicable Walkdown ABO1.18.01 ABO1.18.01-T3 Three (3) cable trays T4-T3 Walkdown ABO1.18.01 ABO1.18.01-T4 Not Applicable Walkdown ABO1.18.01 ABOI.18.01-T5 Four (4) cable trays T5-T4 Walkdown ABO1.18.01 ABO1.18.01-T6 Not Applicable Walkdown ABO1.18.01 ABO1.18.01-T7 Not Applicable Walkdown
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 12 of 32
,o mnpa 6ent, Transient - - CZone comment=, -_-Wkdownr.OrDiawirg-ABO1.18.01 ABO1.18.01-T8 Not Applicable Walkdown ABO1.18.01 AB01.18.01-T9 Not Applicable Walkdown ABO1.18.02 AB01.18.02-T1 Not Applicable Walkdown AB301.18.02 AB01.18.02-T10 Not Applicable Walkdown AB301.18.02 ABO01.18.02-T1 1 T5-T1 1 one cable tray Walkdown AB301.18.02 ABO1.18.02-T12 Not Applicable Walkdown ABO1.18.02 AB01.18.02-T13 Not Applicable Walkdown AB01.18.02 AB01.18.02-T14 Not Applicable Walkdown ABO 1.18.02 ABO01.1 8.02-T2 Not Applicable Walkdown ABO1.18.02 ABO1.18.02-T3 T3-T11 Walkdown ABO1.18.02 ABO1.18.02-T4 Three (3) cable trays from T5-T4 Walkdown ABO1.18.02 ABO1.18.02-T5 Five (5) cable trays from T5-T7 Walkdown AB301.18.02 AB101.18.02-T7 Five (5) cable trays from T5-T7 Walkdown ABO1.18.02 AB01.18.02-T8 Six(6) T8-T9 Walkdown AB01.18.02 ABO1.18.02-T9 Four (4) T9-T10 Walkdown AB01.21.01 AB01.21.01-T1 Two (2) cable trays from T1-T2 Walkdown ABO1.21.01 ABO1.21.01-T2 Two (2) cable trays from T2-T1 Walkdown AB01.21.01 ABO1.21.01-T3 One (1) cable tray from T3-ABO1.21.02 T1 (not applicable: covered by multicompartment Walkdown analysis)
AB01.21.02 AB01.21.02-T1 Eight (8) cable trays from T1- T3 Walkdown AB01.21.02 AB01.21.02-TIO Not Applicable Walkdown ABO1.21.02 AB01.21.02-T1 1 Eight (8) cable trays from T7- T1 1 and Three(3) going from Ti 1-T1 2 Walkdown AB01.21.02 AB01.21.02-T12 Three(3) going from T12-T11 Walkdown AB301.21.02 AB01.21.02-T1 3 Two (2) cable trays from T5-T1 3 Walkdown AB301.21.02 AB01.21.02-T14 Not Applicable Walkdown ABO1.21.02 AB01.21.02-T15 Not Applicable Walkdown AB301.21.02 ABO1.21.02-T2 Not Applicable Walkdown AB301.21.02 ABO1.21.02-T3 Eight (8) cable trays from Ti- T3 and Eight (8) cable trays from T3-T5 Walkdown
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 13 of 32
- p. e......
- m. Cor . ..en, ........ ai AB301.21.02 ABO1.21.02-T5 Eight (8) cable trays from T3-T5, Two (2) cable trays from T5-13, and Eight (8) cable trays Walkdown from T5-T7 AB301.21.02 ABO1.21.02-T6 Not Applicable Walkdown AB301.21.02 ABO1.21.02-T7 Eight cable trays from T5-T7 and Eight (8) cable trays from T7-T1 1 Walkdown AB301.21.02 ABO1.21.02-T8 Not Applicable Walkdown ABO1.29 AB01.29-T1 Two (2) cable trays from AB.01.21.02 (not applicable: covered by multicompartment Walkdown ABO1.29 ABO1.29-T2 One (1) cable tray from T1 -T2 Walkdown A1301.29 AB01.29-T3 One (1) cable tray from T2-T3 Walkdown AB01R.29 AB101.29-T4 Two (2) cable trays from T3-T4 Walkdown CB01.01 CB01.01-T1 Not Applicable D-214-041 CB01.01 CB01.01-T2 Not Applicable D-214-041 CB01.01 CB01.01-T3 Approximately 2 cable trays from T3-T4 and One cable tray from T3-T6 D-214-041 CB01.01 CB101.01-T4 Six (6) cable trays from T4-T5 D-214-041 C101.01 CB01.01-T5 Six (6) cable trays from T4-T5 and Approximately 5 cable trays going from T5- CB02 T1 D-214-041 (not applicable: covered by multicompartment analysis)
CB301.01 CB01.01-T6 One (1) cable tray from T4-T6 and Approximately 8 cable trays going from T6- CB02 (not D-214-041 applicable: covered by multicompartment analysis)
CB02 CB02-TI One (1) cable trays from T1-T2 and Three (3) cable trays from CB02 T1 - CB05 T1 (not D-214-046 applicable: covered by multicompartment analysis)
CB02 CB02-T2 Four cable trays from T1-T2 D-214-046 CB02 CB02-T3 Not Applicable D-214-046 CB04 CB04-TIO Approximately Seventeen (17) cable trays from T9-T10 Walkdown CB04 CB04-Ti 1 Seven (7) cable trays from T1 0-T1i1 Walkdown CB04 CB04-T12 Four (4) cable trays from T3-T12 Walkdown CB04 CB04-T13 Five (5) cable trays from T3-T13 Walkdown CB04 CB04-T3 Five (5) cable trays from T3-T13 and One (1) from T3-T12 Walkdown CB04 CB04-T5 Six (6) cable trays from T5-T6 Walkdown CB04 CB04-T6 Six (6) cable trays from T6-T5 Walkdown CB04 CB04-T7 Thirteen (13) cable trays from T7-T8 Walkdown
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 14 of 32 Mompartinent !rarns n Walk- ...
CB04 CB04-T8 Thirteen (13) cable trays from T8-T7 Walkdown CB04 CB04-T9 Seventeen (17) cable trays from T9-T1 0 Walkdown CB05 CB05-Ti Three (3) cable trays from CB02 T1 - CB05 T1 (not applicable: covered by D-214-046 multicompartment analysis)
CB05 CB05-T2 Not Applicable D-214-046 CB05 CB05-T3 Not Applicable D-214-046 CB17.01 CB17.01-T1 Not Applicable D-214-050 CB20 CB20-Ti Three (3) cable trays from T1-T2 D-214-050 CB20 CB20-T2 Three (3) cable trays from TI-T2 and Four (4) cable trays from T2-T3 walkdown CB20 CB20-T3 Four (4) cable trays from T2-T3 and Two (2) cable trays from T3-T4 walkdown CB20 CB20-T4 Two (2) cable trays from T3-T4 walkdown IB20 IB20-Tl One (1) cable tray from T8-T1 D-214-135 IB20 IB20-TlO Four (4) cable trays from T10-T9 D-214-135 IB20 IB20-Tl 1 One (1) cable tray from Ti1-10 D-214-135 IB20 1120-T2 Two (2) cable trays from T2-T3 D-214-135 IB20 11B20-T3 Four (4) cable trays from T4-T3 D-214-135 IB20 1120-T4 Four (4) cable trays from T9-T4 D-214-135 IB20 1120-T5 One (1) cable tray from T5-T4 and One (1) cable tray from T8-T4 D-214-135 IB20 1120-T8 Four (4) cable trays from T9-T8 and One (1) cable tray from T8-T1 D-214-135 IB20 1120-T9 Four (4) cable trays from T9-T4 and Four (4) cable trays from T10-T9 D-214-135 IB21.01 IB21.01-Ti Three (3) cable trays from T1-T6 Walkdown 1121.01 IB21.01-T2 One (1) cable tray from T2-T7 Walkdown IB21.01 1121.01-T3 One (1) cable tray from T3-T7 Walkdown 1121.01 1121.01-T4 Not Applicable Walkdown 1121.01 1121.01-T5 Approximately Seven (7) cable trays from T6-T5 Walkdown 1R21.01 1121.01-T6 Approximately Seven (7) cable trays from T6-T5 and Three (3) cable trays from T1-T6 Walkdown 1121.01 1R21.01-T7 One cable tray from T3-T7 and One cable tray from T2-T7 Walkdown 1R21.01 IB21.01-T8 Not Applicable Walkdown 1125.01.02 IB25.01.02-TI Seven (7) cable trays from T2-T1 Walkdown
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 15 of 32 a0t enf oi...Com ransientone mmnt , WaIkdown*D raýwihj".,
1125.01.02 1125.01.02-T2 Eight (8) cable trays from T3-T2 Walkdown 1125.01.02 IB25.01.02-T3 Four (4) cable trays from T4-T3 and Four (1) cables trays from T3-T6 Walkdown 1125.01.02 1125.01.02-T4 Four (4) cable trays from T4-T3 and One (1) cable tray from T4-T7 Walkdown 1B25.01.02 1125.01.02-T5 Five (5) cable trays from T5-T6 Walkdown 1B25.011.02 1825.01.02-T6 Five (5) cable trays from T5-T6 Walkdown 1125.01.02 IB25.01.02-T7 Four (4) cable trays from T6-T7 and One (1) cable tray from T4-T7 Walkdown 1125.01.02 IB25.01.02-T8 Four (4) cable trays from T5-T8 Walkdown 1125.01.03 IB25.01.03-Ti Three (3) cable trays from T2-TI Walkdown 1125.01.03 1125.01.03-T2 Three (3) cable trays from T2-T1 and Three (3) cable trays from T2-T4 Walkdown 1125.01.03 IB25.01.03-T3 Not Applicable Walkdown 1125.01.03 IB25.01.03-T4 Three (3) cable trays from T4-T2 Walkdown 1125.01.03 1825.01.03-T5 Not Applicable Walkdown IB25.011.03 IB25.01.03-T6 One (1) cable tray from T4-T6 Walkdown 1125.01.05 IB25.01.05-Ti Four (4) cable trays from 1B25.1.3 TI- 1125.1.2 T7 (not applicable: covered by Walkdown multicompartment analysis) 1125.01.05 IB25.01.05-T2 Not Applicable Walkdown 1125.01.05 1125.01.05-T3 One (1) cable tray from T3- 1125.1.2 T4 (not applicable: covered by multicompartment Walkdown 1125.01.05 1825.01.05-T4 Not Applicable Walkdown 1125.01.05 IB25.01.05-T5 Five (5) cable trays from T5-T3 Walkdown 1125.06.02 IB25.06.02-Ti Not Applicable Walkdown T101.01 TB01,01-T1 Nine (9) cable trays T2-T1 and Eight (8) cable trays from T1-T5 Walkdown TBO1.01 TB01.01-T10 Six (6) cable trays from T12-T10 and Two (2) cable trays from T1 0-13 and Six (6) cable Walkdown trays from T2-T10 TBO1.01 TB01.01-T1 1 Four (4) cable trays from T11 -T13 Walkdown TB01.01 TB01.01-T12 Six (6) cable trays from T12-T10 Walkdown TB301.01 TB01.01-T13 Two (2) cable trays from T10-13 and Four (4) cable trays from T11 -T13 Walkdown TBO1.01 TB01.01-T14 Ten (10) cable trays T9-T14 Walkdown TB301.01 TB01.01-T2 Six (6) cable trays from T2-T10 and Nine (9) cable trays T2-T1 Walkdown TB301.01 TB101.01-T4 Not Applicable Walkdown
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 16 of 32 Wa~d~dn O~DrWing TB01.01 TBO1.01-T5 Eight (8) cable trays from T1-T5 Walkdown TBO1.01 TBO1.01-T7 Not Applicable Walkdown TBO1.01 TBO1.01-T9 Ten (10) cable trays T9-T14 Walkdown TBO1.02 TB01.02-T1 Ten (10) cable trays T1-T2 Walkdown TB01.02 TB01.02-Ti0 Four (4) cable trays from T9-T10 and Four (4) cable trays from T1 0-T11 Walkdown TBO1.02 TBO1.02-T1 1 Four (4) cable trays from T1 0-Ti 1 and Four (4) cable trays from T1 2-T11 Walkdown TBO1.02 TB01.02-T12 Four (4) cable trays from T1 2-T11 Walkdown TBO1.02 TBO1.02-T2 Ten (10) cable trays from T1-T2 Walkdown TBO1.02 TB01.02-T3 Not Applicable Walkdown TBO1.02 TBO1.02-T7 Five (5) cable trays from T7-T9 Walkdown TBO1.02 TBO1.02-T8 Eight (8) cable trays from TI-T8 Walkdown TBO1.02 TBO1.02-T9 Five (5) cable trays from T7-T9 Walkdown TB02 TB02-T I Four (4) cable trays from T1-T2 and Four (4) cable trays from T1-T3 Walkdown TB02 TB02-T2 Four (4) cable trays from T1-T2 and Five (5) cable trays from T2-T3 Walkdown TB02 TB02-T3 Four (4) cable trays from T1-T3 and Five (5) cable trays from T2-T3 Walkdown
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 17 of 32 Based on Table 2 results, a matrix of all applicable exposing and exposed transient zones combinations was compiled. These scenarios do not include fire zones in which a hot gas layer scenario is postulated. In fire zones where a hot gas layer is already postulated, propagation to adjacent transient zones is not necessary because the hot gas layer scenario occurs at times shorter than propagation to adjacent transient zones and consists of damage to the full fire zone. The list of scenarios was separated based on ungrouped and grouped exposing transient zones to facilitate the analysis. An ungrouped transient zone is one in which detailed fire modeling is applied and separate fire scenarios are postulated for all the fixed and transient ignition sources within the transient zone. A grouped transient zone is one in which all the fixed and transient ignition sources are failed completely at time zero.
Starting with the ungrouped transient zones, a total of 170 new scenarios were added to the Fire PRA model. The new scenarios are intended to capture fires that fail the transient zone, and subsequently propagate to adjacent transient zones. Table 3 lists the new scenarios added to the model for the ungrouped scenarios. The table includes the following information: the fire zone where the scenario is postulated; the ignition source ID; a description for the ignition source; the equipment type, which is a mapping to the generic ignition frequency model; equipment type description; and a scenario progression number. The scenario progression number indicates the sequence in which the scenario is postulated. A scenario progression value of 2 indicates that this new scenario propagating to adjacent transient zones is the second in the progression, where the first scenario is damage to the transient zone of fire origin. A scenario progression value of 3 indicates that this new scenario that is propagating to adjacent transient zones is the third in the progression, where the first scenario is damage to the ignition source and immediate cable trays above, and the second scenario is damage to the transient zone of fire origin. These scenarios were quantified for fire ignition frequency, core damage frequency (CDF) and large early release frequency (LERF). The resulting risk values are not among the top contributors in the plant, and do not impact current compliance with the performance criteria.
Table 3: New Scenarios Added to the Fire PRA Model for Ungrouped Transient Zones Fire Zone :Equipment IDD Equipment Description Equpment. EquiSenariypeo.
-,Type- b escrip ion cnal AB.*.'..-....l 2 ,.* AB*
.02 .0 - t,*i *J_--.."*.i,..-t:: * " .21
-: =.. . . . *:l =., . r n.-ie
- "'. .: .,** - -. " 2..g:******
ABOl .21.02 AB3l .21.02-Ti Transient fire #1 postulated at TRCAR Transients 2 floor level.
A1012102A1012102T1 Transient fire #1 postulated at TRWCAR weldng/cutings-floor level.wedn/utg AB301.21.02 ABO1.21.02-T3 Transient floor fire #3 postulated at TRCAR Transients 2 floor level.
level. welding/cutting AB301.21.02 ABO1.21.02-T3 Transient fire #3 postulated at TRWCAR Trans. fires - 2 A301.21.02 AB01.21.02-T3 Transient fire #3 postulated at TRCAR Transients 2 floor level.
AB01 .21.02 AB01 .21 .02-T5 Transient fire #5 postulated at TRCAR Transients 2 floor level.
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 18 of 32 ID~ ~quipiment. E entTyp loe Equipm~ent ID Equipm'enft'Description- uipmen Tp scenario TypeA Description,0 AB01.21.02 AB01.21.02-T5 Transient floor fire #5level.
postulated at TRWCAR Trans. fires -
welding/cutting 2 AB01.21.02 APN9014 RECEPTACEL PANEL 14 EC Electrical cabinets 2 ABO1.21.02 XAH0033 AUX BLDG MCC-SWGR AIR Ventilation 2 HANDLING UNIT Subsystems ELEC H2 RECOMBINER AB01.21.02 'XPN0049A POWER SUPPLY PANEL EC Electrical cabinets 2 AB01.21.02 XPNO050A ELEC H2 RECOMBINER EC Electrical cabinets 2 CONTROL PANEL POST ACCIDENT H2 AB01.21.02 XPN7258A ANALYZER REMOTE PNLA EC Electrical cabinets 2 CONTAINMENT ABO1.21.02 XPN7268A AMTOSPHERE SAMPLING EC Electrical cabinets 2 PANEL ABO1.21.02 XPN98-FS PRE-ACTION SPRINKLER EC Electrical cabinets 2 SYSTEM AB01.21.02 XTF9014 Transformer PX Transformers 2 AB01.21.02 XXS0061-PS VENTED BOX WITH CABLES EC Electrical cabinets 2 CB01.01 CB01.01-T3 Transient fire (postulated at TRCAR Transients 2 floor level) #3 CB01.01 CB01.01-T3 Transient fire (postulated at TRWCAR Trans. fires - 2 floor level) #3 welding/cutting CB01.01 CB01.01-T4 Transient fire (postulated at TRCAR Transients 2 floor level) #4 CB01.01 CB01.01-T4 Transient fire (postulated at TRWCAR Trans. fires - 2 floor level) #4 welding/cutting CB01.01 CB01.01-T5 Transient fire (postulated at TRCAR Transients 2 floor level) #5 CB01.01 CB01.01-T5 Transient fire (postulated at TRWCAR Trans. fires - 2 floor level) #5 welding/cutting CB01.01 CB01.01-T6 Transient fire (postulated at TRCAR Transients 2 floor level)
CB01.01 CB01.01-T6 Transient fire (postulated at TRWCAR Trans. fires - 2 floor level) I welding/cutting CB02 CB02-T1 Transient fire # 1 postulated at TRCAR Transients 2 floor level.
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 19 of 32 Fire Zone Equipment ID~2 ý ,Equiprnent Description vEquipment ~-'Equipm~ent Type Sc6enario2
.... ...... ... = " - -> . *. Desc_ ription3tt CB02 CB02-Tl Transient fire # 1 postulated at TRWCAR Trans. fires - 2 floor level. welding/cutting CB04 CB04-TlO Scenario area for transient TRCAR Transients 2 combustible fires, etc.
CB04 CB04-Tl 0 Scenario area for transient TRWCAR Trans. fires - 2 combustible fires, etc. welding/cutting CB04 CB04-T 1I Scenario area for transient TRCAR Transients 2 combustible fires, etc.
CR04 CB04-Ti I Scenario area for transient TRWCAR Trans. fires - 2 combustible fires, etc. welding/cutting CB04 CB04-T12 Scenario area for transient TRCAR Transients 2 combustible fires, etc.
CR04 CRO4-T12 Scenario area for transient TRWCAR Trans. fires - 2 combustible fires, etc. welding/cutting CB04 CB04-T13 Scenario area for transient TRCAR Transients 2 combustible fires, etc.
CR04 CB04-Tl3 Scenario area for transient TRWCAR Trans. fires - 2 combustible fires, etc. welding/cutting CB04 CB04-T8 Scenario area for transient TRCAR Transients 2 combustible fires, etc.
CR04 CRO4-T8 Scenario area for transient TRWCAR Trans. fires - 2 combustible fires, etc. welding/cutting IB21.01 IB21.01-T1 Transient fire # 1 postulated at TRPW Transients 2 floor level.
11321.0 11R2i.01-Ti Transient fire # 1 postulated at TRWPW Trans. fires - 2 floor level. welding/cutting 121.011 XCA0001A XCAiA-CR - XCA000iA S.S. EC Electrical cabinets 2 POWER CABINET 1AC 1121.01 XCA0001B XCA1B-CR EC Electrical cabinets 2 IR211.01 XCA0002A XCA2A-CR EC Electrical cabinets 2 IB21.01 XCA0002B XCA2B-CR EC Electrical cabinets 2 XCA0004 DC HOLD CAB 1121.01 XCA0004 (INCLUDING P/A EC Electrical cabinets 2 CONVERTER) 1121.01 XCA001 1 XCA0011 EC Electrical cabinets 2
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 20 of 32 SEquipment EqimntTp Dypecriptiptin 1121.01 XCLOO03 XCL3CR EC Electrical cabinets 2 1121.01 XXS0047-PS VENTED BOX WITH CABLES EC Electrical cabinets 2 11325.01.02 APN4011 IB WELD. RECEPT. 480/277 EC Electrical cabinets 3 DIST PANEL 1B25.01.02 APN8033 LIGHTING PANEL EC Electrical cabinets 2 1125.01.02 APN8035A LIGHTING PANEL EC- Electrical cabinets 3 1B25.01.02 APN8036B LIGHTING PANEL EC Electrical cabinets 3 1125.01.02 APN9008 RECEPTACLE PANEL 8 EC Electrical cabinets 2 1125.01.02 DPN1HX DPN-1HX-ED EC, Electrical cabinets 3 1825.01.02 IB25.01.02-T2 Scenario area for transient TRPW Transients 2 combustible fires, etc.
1125.01.02 IB25.01.02-T2 Scenario area for transient TRWPW Trans. fires - 2 combustible fires, etc. welding/cutting 1125.01.02 IB25.01.02-T3 Scenario area for transient TRPW Transients 2 combustible fires, etc.
1125.01.02 IB25.01.02-T3 Scenario area for transient TRWPW Trans. fires - 2 combustible fires, etc. welding/cutting 1825.01.02 IB25.01.02-T4 Scenario area for transient TRPW Transients 2 combustible fires, etc.
Scenario area for combustible transient fires, etc. TRWPW Trans. fires -
welding/cutting IB25.01.02 IB25.01.02-T5 Transient fire (postulated at TRPW Transients 2 floor level)
IB25.01.02 IB25.01.02-T5 Transient fire (postulated at TRWPW Trans. fires - 2 floor level) welding/cutting 1125.01.02 IB25.01.02-T6 Scenario area for transient TRPW Transients 2 combustible fires, etc.
825.01.02 11825.01 .02-T6 Scenario area for transient TRWPW Trans. fires - 2 combustible fires, etc. welding/cutting 1825.01.02 IB25.01.02-T7 Scenario area for transient TRPW Transients 2 combustible fires, etc.
1325.011.02 1825.01.02T7 Scenario area for transient TRWPW Trans. fires - 2 combustible fires, etc. welding/cutting
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 21 of 32 Fire Zone qimn ID Equipmen DesEquipment uint T Se.cenario Equimen areanDesripionType foTtrnsen Equipent., esrptioh 1B25.01.02 IB25.01.02-T8 Scenario area for transient TRPW Transients 2 combustible fires, etc.
1825.01 .02-T8 Scenario area for transient TRWPW Trans. fires -
combustible fires, etc. welding/cutting 1125.01.02 XBC1X BATTERY CHARGER 1X BC Battery Chargers 3 IB25.01.02 XBC1X-2X BATTERY CHARGER 1X-2X BC Battery Chargers 3 825.01 .02 XPPOO001 B COMPONENT COOLING PMP Pumps 2 PUMP B 11325.01.02 XPPOO001B COMPONENT COOLING Fire with 100% of PUMP B Oil 825.01.02 XPPOO001 B COMPONENT COOLING Z02 Fire with 10% of 2 PUMP B Oil 11325.01.02 XPPOO45B SERVICE WATER BOOSTER PMP Pumps 2 PUMP B 11325.01.02 XPPO45B SERVICE WATER BOOSTER Fire with 100% of PUMP B Oil 825.01 .02 XPPOO45B SERVICE WATER BOOSTER Z02 Fire with 10% of 2 PUMP B Oil COMPONENT COOLING IB25.01.02 XPP0058A BOOSTER PUMP A ZOl Fire with 100% of 3 XPP0058A-CC COMPONENT COOLING Fire with 10% of 1B25.01.02 XPP0058A BOOSTER PUMP A Z02 Oil XPP0058A-CC Oil IB25.01.02 XPP0058B COMP COOLING BOOSTER ZO1 Fire with 100% of 3 PUMP B XPP0058B-CC Oil 1825.01.02 XPPOO58B COMP COOLING BOOSTER Z02 Fire with 10% of 2 PUMP B XPP0058B-CC Oil 18325.01.02 XPPOO58C COMPONENT COOLING PMP Pumps 2 BOOSTER PUMP C 1825.01.02 XPPOO58C COMPONENT COOLING Fire with 100% of BOOSTER PUMP C Oil 1825.01.02 XPPOO58C COMPONENT COOLING Z02 Fire with 10% of 2 BOOSTER PUMP C Oil IB25.01.02 XXS-0054-PS VENTED BOX WITH CABLES EC Electrical cabinets 3 IB25.01.03 10451 Cooling Unit Fans VSS Ventilation 2
___ ______________________Subsystems
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 22 of 32 eEquipment A~r6 Zo n ev..EquipmenitID Equiipment DescriTtpen 1825.01.03 1825.01 .03-T6 Scenario area for transient TRPW combustible fires, etc.
11325.01.03 IB25.01.03-T6 Seaiarafrtnsnt TRWPW combustible fires, etc.
11325.1.03 XN0044 CHILLER WATER TANK & E PUMP CONTROL PANEL 11325.01.03 XPN5121 LCNT A FREC XPP0102A&B B25.01.03 XPN5554 DC SYS TR X GND DET& UV EC RELAY PNL 1125.01.03 XTF9008-EM TRANSFORMER PX T13O1.01 RML001 1 WI BACKWASH EFFLUENT EC RAD MONITOR TB01.01 TB01.01-T1 Transient fire # 1 postulated at TRTB floor level.
TB101.01 TB01.01-T1 Transient fire # 1 postulated at TRWTB floor level.
TB101.01 TB01.01-T5 Transient fire # 5 postulated at TRTB floor level.
TB01.01 TBO1.01-T5 Transient fire # 5 postulated at TRWTB floor level.
TB01.01 xdr0004A Instrument Air Dryer EC TROl 01 XPNO051A CONDENSATE PUMP DRIVE EC CONTROL PANEL A T13O1.01 XPNO051 B CONDENSATE PUMP DRIVE EC CONTROL PANEL B TBO1.01 XPNO051 C CONDENSATE PUMP DRIVE EC CONTROL PANEL C T1301.01 XPNO091 IAM MOUNTING PANEL FOR EC CB PRE-ACTION SYS TB01.01 XPNO130 SIMPLEX 4100 UT TB-2 EC TBO1.01 XPNO208 STATOR LEAK MONITORING EG SYS PANEL TBO1.01 XPN5143 LOC CONTR XPP0042BSTAT FOR EC TBOI.01 XPN5144 LOC CONTR XPP0042CSTAT FOR EC
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 23 of 32
.Fire Zone~ '.' q`0 m$' t1,Equipmentlecr o TB01.01 XPN5171 LOC CONTR STA TBO1.01 XPN7201 XPN 7201 Hydrogen & Stator Cooling Water Control Panel TB01.01 XPP0153APU WI BACKWASH TRANSFER A
PUMP A TB01.01 XPP0153B WI BACKWASHPM TRANSFER PUMP B TB01.01 XPP0168AA WI LINER TRANSFER PUMP A
TBO1.01 XPP0168B WI LINER TRANSFER PUMP B
GEN CLGBKR CLOSED CYCLE BOOSTER PUMP A GEN BKR CLOSED CYCLE CLG BOOSTER PUMP B MAIN SEAL OIL PUMP TB.01 XPT0001-PPXPT0001-PP TB01.01 XPTO00OI-PP1XTO1-P MAIN SEAL OIL PUMP XPT0001-PP1 TB01.01 XPT0001-PP1XTO1-P MAIN SEAL OIL PUMP XPT0001-PP1 TBO1.01 XPT0001-PP2 Seal Oil Recirculation Pump TB01.01 XPT0001-PP2 Seal Oil Recirculation Pump T1301.01 XPT0001-PP2 Seal Oil Recirculation Pump EMERGENCY SEAL OIL TB01.01 XPT001-PP3XPT001-PP3 XPT0001-PP3 EMERGENCY SEAL OIL TBO1.01 PUMP XPT0001-PP3 -P TB01 .01 XPT0001-PPMPPT30 PUMP XPT0001-PP3 EMERGENCY SEAL OIL TB01.01 XPT0001-PP4 SEAL OIL VACUUM PUMP TB01.01 XPT0001-PP4 SEAL OIL VACUUM PUMP TB01.01 XPT0001-PP4 SEAL OIL VACUUM PUMP
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 24 of 32
,*r o-e, Zoe Euipment I D
- q**re , Desc'riptio .
50.u.pmyn "qui' Type.D -o.escripent..
tion Ty e io -,.
TBO1.01 XPT0002-PP1 STATOR COOLING PUMP A PMP Pumps
- - ~. 2 STATOR COOLING PUMP A Fire with 100% of TBO1.01 xPT0002-PP1 zol Oil 2
X1 i STATOR COOLING PUMP A Fire with 10% of TBO1.01 xPT0002-PP1 Z02 Oil 2
TBO1.01 xPT0002-PP2 STATOR COOLING PUMP B PMP Pumps 2 i
T1301.01 STATOR COOLING PUMP B Fire with 100% of xPT0002-PP2 ZO1 Oil 2
TBO1.01 xPT0002-PP2 STATOR COOLING PUMP B Fire with 10% of Z02 2 Oil STARTER FOR MAIN TURB TBO1.01 XSX0004 EMER SEAL OIL PUMP- EC Electrical cabinets VENTED BOX TURBINE BLDG 480/277 VAC TBO1.02 APN4015 DIST PANEL EC Electrical cabinets TURBINE BLDG 208/120 VAC TBO1.02 APN5016 DIST PANEL EC Electrical cabinets
-1 -4 -----
Transient fire # 1 postulated at TBO1.02 TB01.02-T1 floor level. TRTB Transients Transient fire # 1 postulated at TB01.02 TB01.02-T1 Trans. fires -
floor level. TRWTB welding/cutting
-4 Transient fire # 7 postulated at T1301.02 TBO1.02-T7 TRTB floor level Transients TBO1.02 Transient fire # 7 postulated at Trans. fires -
TBO1.02-T7 floor level TRWTB welding/cutting I IL 4-TBO1.02 Transient fire (postulated at TBO1.02-T8 floor level) TRTB Transients Transient fire (postulated at Trans. fires -
TBO1.02 TBO1.02-T8 floor level) TRWTB welding/cutting TB01.02 Gen ISO Phone Duct Fans Ventilation XBDO005 VSS Subsystems ALTERREX i4 TB01 .02 XEX0002 EXCITER/REGULATOR EC Electrical cabinets CUBICAL VOLT REGULATOR PWR POT Transformers TBO1.02 XE-X0002-PPT1 XFMR PPT-1 PX 2 (Oil/dry)
TBO1.02 XEXOOO2-PPT2 VOLT REGULATOR PWR POT Transformers 2 XFMR PPT-2 (Oil/dry)
Document Control Desk CR-06-00055 Attachment I RC-1 3-0054 Page 25 of 32 Fire Zone1 Eqim~ ID~E upent Dbescripion'uimtTpType bDescription- Scenari'!
TBO1.02 XFN0088A GENERATOR NEUTRAL Ventilation 2 COOLING FAN A Subsystems TB31.02 XFN0088B GENERATOR NEUTRAL Ventilation 2 COOLING FAN B Subsystems MCC - XMCBIYTURBINE TB01.02 XMC1B1Y BLDG MOTOR CONTROL EC Electrical cabinets 2 CENTER 1BIY TBO1.02 XPNO087 Control Panel XPN-87 WI EC Electrical cabinets 2 (large walk-in)
CONDENSATE POLISHER TBO1.02 XPN5437 DEWATERPNGICNTR DEWATERING CNTRL PNL EC Electrical cabinets 2 GENERATOR WINDING TBO1.02 XPN7276 TEMERATUR TEMPERATURE SCNNE SCANNER EC Electrical cabinets 2 TBO1.02 XPP0151A WI DEMINERALIZER A PMP Pumps 2 HOLDING PUMP T101.02 XPP0151A WI DEMINERALIZER A Fire with 100% of 2 HOLDING PUMP Oil TBO1.02 XPP0151A WI DEMINERALIZER A Z02 Fire with 10% of 2 HOLDING PUMP Oil TBO1.02 XPP0151B WI DEMINERALIZER B PMP Pumps 2 HOLDING PUMP TBO1.02 XPP0151B WI DEMINERALIZER B Fire with 100% of 2 HOLDING PUMP Oil TBO1.02 XPP0151B WI DEMINERALIZER B Z02 Fire with 10% of 2 HOLDING PUMP Oil TBO1.02 XPP0151C WI DEMINERALIZER C PMP Pumps 2 HOLDING PUMP TB31.02 XPP0151C WI DEMINERALIZER C Fire with 100% of 2 HOLDING PUMP Oil TBO1.02 XPP0151C WI DEMINERALIZER C Z02 Fire with 10% of 2 HOLDING PUMP Oil TBO1.02 XPP0152 WI PRECOAT TRANSFER PMP Pumps 2 PUMP TBO1.02 XPP0152 WI PRECOAT TRANSFER Fire with 100% of 2 PUMP Oil T131.02 XPP0152 WI PRECOAT TRANSFER Z02 Fire with 10% of 2 PUMP Oil T13O1.02 XPP0167 WI SPENT RESIN LINER PMP Pumps DEWATERING PUMP
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 26 of 32 Fir Z o....ne.*.
- , Equ ipm.en..
- iE quipmen t e..* "T-p FrZoe Eq,uipment ID~ Equipment Description Eqimn
~Tp ' ~ qipetTp escription D cenario-*-
TB101.02 XSR0007 Sodium Analyzer Rack EC Electrical cabinets 2 TB01.02 XSR0008 FILTER/DEMINX SODIUM EC Electrical cabinets 2 SAMPLING RACK TB01.02 XSW1A1 939 KVA RUNNING LOAD EC Electrical cabinets 2 TB01.02 XSW1A1 939 KVA RUNNING LOAD LVHEAF Low voltage 2 HEAF TB01.02 XTF01A1 TRANSFORMER,1OKVA,XSW HVHEAF High voltage 2 WA1 HEAF TB01.02 XTF01A1 TRANSFORMER,1OKVA,XSW PX Transformers 2 WA1 (Oil/dry)
TB01.02 XTF1A1 TRANSFORMER XTF1A1-ES HVHEAF High voltage 2 HEAF Transformers TB101.02 XTF1A1 TRANSFORMER XTF1A1-ES PX TOil/dry) 2 (Oil/dry)
TB01.02 XTF5016 TRANSFORMER PX Transformers 2 (Oil/dry)
TB01 .02 XTF9043-TI TRANSFORMER Trnsomes2
_____ ____ _____ ____(Oil/dry) _ _ _ _ _
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 27 of 32 For the grouped transient zones, in which all the fixed and transient ignition sources are failed completely at time zero, a slightly different analysis is necessary from the preceding analysis, which involves ungrouped transient zones only. Since grouped transient zones do not have separate fire scenarios for each ignition source, adding scenarios to the Fire Modeling Database is not readily accomplished. Therefore, for the grouped transient zones, the matrix of exposed and exposing transient zones is used to identify risk contributing transient zone combinations.
The CDF for all the scenarios with propagation are calculated and summed and are compared to the CDF of the scenarios in which propagation was not included.
The scenarios for which walkdowns show that cable trays extend across transient zone boundaries for grouped transient zones are provided in Table 4. For each scenario, the core damage frequency (CDF) was calculated as follows:
CDF = IGF x (PNs x CCDPWith prop + (1-PNS) x CCDPno prop) where IGF is the ignition frequency for the exposing transient zone as a whole, which is a combination of all ignition sources (i.e., transient and fixed ignition sources) within that transient zone; PNS is the nonsuppression probability, calculated with the equation exp(-At), where t is time to damage and Ais a suppression curve constant, which varies for different types of fires, as discussed in Supplement 1 of NUREG/CR-6850. CCDPWith prop is the conditional core damage probability for the scenario in which all the targets in both transient zones (i.e. exposing and exposed transient zones) are damaged, calculated with the Fire PRA model; CCDPno prop is the conditional core damage probability for the scenario in which the fire does not spread to the adjacent transient zone and only the targets in the exposing transient zone are damaged. For those exposing transient zones, such as ABO1.21.02-T1 1, which are paired with more than one exposing transient zone, the CCDP for the highest scenario was used for CCDPWith prop in the calculation. The time to damage was calculated to be 67 minutes, based on the flame spread rate of 0.059 ft/min (0.3 mm/s) for thermoset cables recommended in NUREG/CR-701 0 and the distance of 4 ft that the fire would need to propagate through the overlap cable trays to reach targets in the adjacent transient zone. The suppression curve constant, A, in the PNS equation, varies with the type of fire and was conservatively taken to be the highest value for any of the ignition sources in the exposing transient zone. A minimum PNS value of 0.001 was used, as recommended in Supplement 1 to NUREG/CR-6850. In some cases, PNS was set equal to 1.0 because the CCDPwith prop was the same or only slightly larger than CCDPno prop., suggesting that no new targets would be impacted by a propagating fire into the adjacent transient zone. The total CDF values are listed in Table 4. The last column in Table 4 gives the CDF already included in the Fire PRA quantification. The totals are summed at the bottom of Table 4. The results show that the additional CDF contribution by including the propagation between transient zones due to grouped transient zones is 1.4E-06, which does not affect the compliance limits for CDF, LERF, or delta values. The Generic Methodology calculation, DC0780B-001 will be updated to reflect this analysis.
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 28 of 32 Table 4: CDF for Grouped Transient Zones with Potential for Propagation to Adjacent Transient Zones
,SenrioAI D -N .iposinig',
E P';* : .... C.CDPb ...... _ VCP vvithBaeae Totalg D' 6*p-r' b ABO1.04-T1 -TO-ABO1.04-T2 2.12E-05 0.001 2.02E-08 1.28E-03 2.76E-1 1 4.28E-13 ABO1.04-T2-TO-ABO1.04-Ti 1.90E-04 0.001 1.28E-03 1.28E-03 2.43E-07 2.43E-07 ABO1.04-T2-TO-ABO1.04-T7 1.90E-04 0.001 1.28E-03 1.28E-03 Note 1 Note 1 ABO1.04-T2-TO-ABO1.04-T8 1.90E-04 0.001 1.28E-03 1.28E-03 Note 1 Note 1 ABO1.04-T7-TO-ABO1.04-T2 5.21 E-05 0.001 2.02E-08 1.28E-03 7.28E-1 1 1.05E-12 ABO1.04-T7-TO-ABO1.04-T9 5.21 E-05 0.001 2.02E-08 2.21 E-05 Note 1 Note 1 ABO1.04-T8-TO-ABO1.04-T2 2.45E-04 0.001 7.64E-05 1.28E-03 1.90E-08 1.87E-08 ABO1.04-T9-TO-ABO1.04-T7 1.14E-04 1 2.21 E-05 2.21E-05 2.52E-09 2.52E-09 ABO1.08.02-T1 -TO-ABO1.08.02-T2 6.61 E-06 0.001 2.95E-07 1.28E-03 1.04E-11 1.95E-12 ABO1.08.02-T2-TO-ABO1.08.02-T1 1.11E-05 0.001 1.28E-03 1.28E-03 1.42E-08 1.42E-08 ABO1.08.02-T3-TO-ABO1.08.02-T4 8.69E-06 0.001 1.28E-03 1.28E-03 1.11 E-08 1.11 E-08 ABO1.08.02-T4-TO-ABO1.08.02-T3 1.20E-05 0.001 1.28E-03 1.28E-03 1.54E-08 1.54E-08 ABO1.08.02-T4-TO-ABO1.08.02-T5 1.20E-05 1 1.28E-03 1.28E-03 Note 1 Note 1 ABO1.08.02-T5-TO-ABO1.08.02-T4 1.02E-05 0.001 5.46E-07 1.28E-03 1.86E-1 1 5.57E-12 ABO1.09-T3-TO-ABO1.09-T4 5.42E-06 0.001 1.42E-03 1.56E-03 7.70E-09 7.70E-09 ABO1.09-T4-TO-ABO1.09-T3 3.70E-05 0.006 1.28E-03 1.56E-03 4.74E-08 4.74E-08 ABO1.10-T13-TO-ABO1.10-T14 3.24E-04 1 2.72E-06 2.72E-06 8.81E-10 8.81E-10 ABO1.10-T14-TO-ABO1.10-T13 4.12E-04 1 2.72E-06 2.72E-06 1.12E-09 1.12E-09 AB01.10-T14-TO-ABO1.10-T15 4.12E-04 1 NA NA Note 2 NA ABO1.10-T15-TO-ABO1.10-T14 6.69E-05 1 NA NA Note 2 NA ABO1.18.01-T3-TO-ABO1.18.01-T4 1.04E-04 1 NA NA Note 2 NA ABO1.18.01-T4-TO-ABO1.18.01-T3 1.32E-04 1 NA NA Note 2 NA ABO1.18.01-T4-TO-ABO1.18.01-T5 1.32E-04 1 NA NA Note 2 NA ABO1.18.01-T5-TO-ABO1.18.01-T4 1.87E-05 1 NA NA Note 2 NA
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 29 of 32
~.Scenario ID Exosn 4.MRI -,CCDP no--wih CCD Ttl Dihk opop
. prp ionFPSpropagakioný- AtY i AB0 1.18.02-T10 -TO-AB1. 18.02-T9 1.45E-05 1 4.12E-07 4.12E-07 5.97E-12 5.97E-12 AB1. 18.02-T11 TO-AB1. 18.02-T3 5.78E-05 0.006 1.78E-05 5.03E-05 1.04E-09 1.03E-09 AB01.18.02-T11-TO-AB01.18.02-T5 5.78E-05 1 1.78E-05 5.03E-05 Note 1 Note 1 ABO1.18.02-T3-TO-AB01.18.02-Ti 1 1.85E-04 0.001 3.05E-07 5.03E-05 6.64E-1 1 5.64E-1 1 ABO1.18.02-T4-TO-ABO1.18.02-T5 2.76E-04 0.001 4.12E-07 1.50E-06 1.14E-10 1.14E-10 ABO1.1 8.02-T5-TO-ABO1.18.02-T1 1 2.32E-04 0.001 2.09E-08 5.03E-05 1.74E-1 1 4.85E-12 ABO1.18.02-T5-TO-ABO1.18.02-T4 2.32E-04 1 2.09E-08 1.50E-06 Note 1 Note 1 ABO1.18.02-T5-TO-ABO1.18.02-T7 2.32E-04 1 2.09E-08 8.67E-07 Note 1 Note 1 ABOI.18.02-T7-TO-ABOI.18.02-T5 1.1 2E-05 1 2.02E-08 8.67E-07 9.71 E-12 2.26E-13 ABO1 .18.02-T8-TO-ABO1 .18.02-T9 1.73E-05 1 2.02E-08 2.02E-08 3.49E-13 3.49E-13 ABO1 .18.02-T9-TO-ABO1 .18.02-T1 0 1.29E-05 1 2.02E-08 4.12E-07 5.31 E-12 2.61E-13 ABO1.18.02-T9-TO-ABO1.18.02-T8 1.29E-05 1 2.02E-08 2.02E-08 Note 1 Note 1 ABO1.21.01-Ti-TO-ABO1.21.01-T2 1.76E-04 1 1.62E-04 1.05E-05 1.85E-09 2.85E-08 ABO1.21.01-T2-TO-ABO1.21.01-Ti 1.25E-04 1 1.05E-05 1.05E-05 1.31 E-09 1.31 E-09 ABO1.21.02-Ti 1-TO-ABO1.21.02-Ti 2 6.37E-04 0.001 4.14E-07 2.26E-04 4.18E-10 2.64E-1 0 ABO1.21.02-T11-TO-ABO1.21.02-T7 6.37E-04 1 4.14E-07 4.14E-07 Note 1 Note 1 ABO1.21.02-Ti 2-TO-ABO1.21.02-Ti 1 4.01 E-04 0.001 4.12E-07 2.26E-04 2.63E-10 1.65E-1 0 ABO1.21.02-T13-TO-ABO1.21.02-T5 6.98E-05 1 2.90E-05 2.90E-05 2.02E-09 2.02E-09 ABO1.21.02-T7-TO-ABO1.21.02-TI1 6.13E-05 1 4.14E-07 4.14E-07 Note 1 Note 1 ABO1.21.02-T7-TO-ABO1.21.02-T5 6.13E-05 0.001 4.14E-07 2.90E-05 2.73E-1 1 2.54E-1 1 ABO1.29-T1-TO-ABO1.29-T2 6.08E-04 1 NA NA Note 2 NA ABO1.29-T2-TO-ABO1.29-Ti 9.01 E-04 1 NA NA Note 2 NA ABO1.29-T2-TO-ABO1.29-T3 9.01 E-04 1 NA NA Note 2 NA ABO1.29-T3-TO-ABO1.29-T2 5.27E-04 1 NA NA Note 2 NA ABO1.29-T3-TO-ABO1.29-T4 5.27E-04 1 NA NA Note 2 NA ABO1.29-T4-TO-ABO1.29-T3 5.15E-04 1 NA NA Note 2 NA
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 30 of 32 n 0poaain~poaain~
CB02-T2-TO-CB02-Ti 1.53E-05 1 NA NA Note 2 NA C804-T3-TO-CB04-T12 1.87E-05 0.001 1.65E-03 2.56E-03 Note 1 Note 1 CBO4-T3-TO-CB04-T1 3 1 .87E-05 0.001 1 .65E-03 1 .37E-01 3.34E-08 3.09E-08 CB04-T5-TO-C B04-T6 1.51 E-05 0.001 6.77E-04 6.45E-04 1 .02E-08 1 .02 E-08 C B04-T6-TO-CB04-T5 1.59E-05 0.001 6.95E-04 6.45E-04 1.10E-08 1.11E-08 CB04-T7-TO-CBO4-T8 9.84E-06 1 NA NA Note 2 NA CB04-T9-TO-CB04-T10 3.92E-06 1 NA NA Note 2 NA CB20-T1-TO-CB20-T2 1 .53E-05 1 NA NA Note 2 NA CB20-T2-TO-CB20-T1 2.90E-06 1 NA NA Note 2 NA CB20-T2-TO-CB20-T3 2.90E-06 1 NA NA Note 2 NA CB20-T3-TO-CB20-T2 1 .62E-05 1 NA NA Note 2 NA CB20-T3-TO-CB20-T4 1 .62E-05 1 NA NA Note 2 NA CB20-T4-TO-CB20-T3 3.06E-06 1 NA NA Note 2 NA IB20-T1 0-TO-IB20-T1 1 4.01 E-04 0.001 7.11 E-06 7.11 E-06 2.85E-09 2.85E-09 IB20-T10-TO-1B20-T9 4.01 E-04 1 7.11E-06 7.11E-06 Note 1 Note 1 IB20-T1 1-TO-I1B20-T1 0 4.00E-04 0.001 7.11 E-06 7.11 E-06 2.84E-09 2.84E-09 IB20-T1-TO-IB20-T8 7.50E-04 0.479 1.96E-05 9.87E-05 4.31E-08 1.47E-08 IB20-T2-TO-I B20-T3 7.55E-04 0.479 1 .96E-05 1 .96E-05 1 .48 E-08 1 .48 E-08 IB20-T3-TO-I B20-T2 5.34E-04 0.479 1 .96E-05 1 .96E-05 1 .05E-08 1 .05E-08 IB20-T3-TO-IB20-T4 5.34E-04 1 1.96E-05 1.96E-05 Note 1 Note 1 IB20-T4-TO-IB20-T3 1.17E-04 1 1.96E-05 1.96E-05 Note 1 Note 1 IB20-T4-TO-IB20-T5 1.17E-04 1 1.96E-05 1.96E-05 Note 1 Note 1 IB20-T4-TO-IB20-T8 1.1 7E-04 0.479 1.96E-05 9.87E-05 6.72E-09 2.29E-09 IB20-T4-TO-IB20-T9 1.17E-04 1 1.96E-05 7.11E-06 Note 1 Note 1 IB20-T5-TO-1B20-T4 3.78E-04 0.479 1.96E-05 1.96E-05 7.41E-09 7.41E-09 IB20-T8-TO-IB20-T1 2.62E-04 0.479 9.87E-05 9.87E-05 2.59E-08 2.59E-08
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 31 of 32 Scenaio IDExposing Scearo I, NSTotl ccDR.ln CCDP with. ~n rnqnrn.,ana+mn.
IGF PNSpa propagationsTtICD Yconsider'ed 1B20-T8-TO-IB20-T4 2.62E-04 0.479 9.87E-05 9.87E-05 Note 1 Note 1 1B320-T8-TO-1B320-T9 2.62E-04 0.479 9.87E-05 9.87E-05 Note 1 Note 1 IB20-T9-TO-IB20-T10 4.OOE-04 1 7.11 E-06 7.11 E-06 Note 1 Note 1 I820-T9-TO-IB20-T4 4.OOE-04 1 7.11 E-06 7.11 E-06 Note I Note 1 IB20-T9-TO-IB20-T8 4.00E-04 0.001 7.11 E-06 9.87E-05 2.88E-09 2.84E-09 11321.01 -T2-TO-1B21 .01 JT7 9.04E-06 1 2.74E-06 2.74E-06 2.48E-1 1 2.48E-1 1 IB21.01-T3-TO-IB21.01-T7 6.02E-06 1 2.74E-06 2.74E-06 1.65E-1 1 1.65E-1 1 1821.01 -T5-TO-IB21 .01 -T6 1.03E-04 0.479 2.85E-05 2.85E-05 2.94E-09 2.94E-09 IB21.01-T6-TO-IB21.01 -T1 2.78E-06 1 2.85E-05 4.97E-05 1.38E-10 7.92E-1 1 18321 .01-T6-TO-1B321 .01-T5 2.78E-06 1 2.85E-05 2.85E-05 Note 1 Note 1 IB21.01-T7-TO-I821.01-T2 1.26E-05 1 2.74E-06 2.74E-06 3.45E-1 1 3.45E-11I 11321 .01 -T7-TO-IB21 .01-T3 1.26E-05 1 2.74E-06 2.74E-06 Note 1 Note 1 1825.01.03-Ti -TO-IB25.01 .03-T2 1.1 9E-05 0.001 4.83E-06 5.94E-04 6.45E-1 1 5.75E-1 1 IB25.01.03-T2-TO-IB25.01.03-T1 9.87E-05 0.006 5.94E-04 5.94E-04 5.86E-08 5.86E-08 8B25.01 .03-T2-TO-1B25.01 .03-T4 9.87E-05 1 5.94E-04 5.94E-04 Note 1 Note 1 1825.01 .03-T4-TO-1825.01 .03-T2 5.67E-06 0.006 2.44E-08 5.94E-04 2.08E-1 1 1.38E-1 3 1825.01 .03-T4-TO-IB25.01 .03-T6 5.67E-06 1 2.44E-08 2.55E-05 Note 1 Note 1 1825.01 .05-T3-TO-1825.01 .05-T5 1.07E-05 1 3.1 5E-07 3.1 5E-07 3.37E-1 2 3.37E-1 2 1825.01 .05-T5-TO-1825.0i .05-T3 1.29E-05 1 3.1 5E-07 3.1 5E-07 4.06E-1 2 4.06E-1 2 TBO1.01-T1O-TO-TBO1.01-T12 1.05E-03 1 2.02E-08 2.02E-08 Note 1 Note I TBOI.01-T1O-TO-TBOi.01-T13 1.05E-03 1 2.02E-08 2.02E-08 Note 1 Note 1 TBO1.01-T1O-TO-TBOI.0i-T2 1.05E-03 0.187 2.02E-08 1.11E-05 2.20E-09 2.12E-1 1 TBOI.01 -T1 1-TO-TBOI.0i -T1 3 4.01 E-04 1 2.02E-08 2.02E-08 8.10E-12 .8.10E-12 T13i1.01 -TI 2-TO-TBOI .01 -Ti 0 1.14E-03 1 2.02E-08 2.02E-08 2.30E-1 I 2.30E-1 1 TBOi.0i -T1 3-TO-TBO1.0i -T1i0 7.99E-04 1 2.02E-08 2.02E-08 1.61 E-1i1i.61 E-1i1 TBOi.0i -T1 3-TO-TBO1.01 -T1i1 7.99E-04 I 2.02E-08 2.02E-08 Note 1 Note 1
Document Control Desk CR-06-00055 Attachment I RC-13-0054 Page 32 of 32
,,E.:osing
. :. *DP no C.D.with 707,Case.*.
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... ......... ..... =. *. , , f." .,.,
TBO1.01-T14-TO-TBO1.01 T9 1.07E-03 0.187 1.11E-05 1.11E-05 1. 19E-08 1.19E-08 TB01.01-T2-TO-TBO1.01 -T1 6.89E-04 0.187 1.11E-05 6.45E-04 8.95E-08 7.65E-09 TB01.01-T2-TO-TBO1.01-T10 6.89E-04 1 1.11E-05 1.11E-05 Note 1 Note 1 TB01.01-T9-TO-TB01.01-T14 2.94E-04 0.187 1.11 E-05 1.11 E-05 3.26E-09 3.26E-09 TB01.02-T10-TO-TBO1.02-T11 6.28E-04 1 2.02E-08 2.02E-08 Note 1 Note 1 TB01.02-T1 0-TO-TBO1.02-T9 6.28E-04 0.187 2.02E-08 1.11 E-05 1.32E-09 1.27E-1i1 TB01.02-T1 1-TO-TBO1.02-Ti 0 6.38E-03 1 2.02E-08 2.02E-08 1.29E-10 1.29E-10 TB01.02-T11-TO-TBO1.02-T12 6.38E-03 1 2.02E-08 2.02E-08 Note 1 Note 1 TB01.02-T1 2-TO-TBOI.02-T 1i 5.76E-04 1 2.02E-08 2.02E-08 1. 16E-1i1 1.16E-11 TB01.02-T2-TO-TB01.02-T1 5.59E-04 0.187 1.17E-04 6.41E-03 7.24E-07 6.54E-08 TB01.02-T9-TO-TBO1.02-T10 3.56E-04 1 1.11E-05 1.11E-05 Note 1 Note 1 TBO1.02-T9-TO-TBO1.02-T7 3.56E-04 0.187 1.11 E-05 6.41 E-03 4.31 E-07 3.95E-09 TB02-Tl -TO-TB02-T2 9.06E-04 0.479 6.24E-04 6.44E-04 5.74E-07 5.65E-07 TB02-TI-TO-TB02-T3 9.06E-04 0.479 6.24E-04 6.24E-04 Note 1 Note 1 TB02-T2-TO-TB02-T1 6.83E-04 0.479 6.44E-04 6.44E-04 4.40E-07 4.40E-07 TB02-T2-TO-TB02-T3 6.83E-04 0.479 6.44E-04 6.44E-04 Note 1 Note 1 TB02-T3-TO-TB02-T1 5.89E-04 0.479 4.14E-07 6.24E-04 Note 1 Note 1 TB02-T3-TO-TB02-T2 5.89E-04 0.479 4.14E-07 6.44E-04 1.82E-07 2.44E-10 SUM 3.06E-06 1.69E-06 Total CDF Increase Due to Propagation Across Transient Zone Boundaries 1.37E-06 Notel: This scenario has a CCDP that is equal to or less than another scenario involving the same exposing transient zone. In order to apportion the ignition frequency correctly, only one combination per exposing transient zone is included in the calculation.
Note 2: One or both of the CCDP values is less than 2E-08, and therefore not a significant risk contributor.
Document Control Desk CR-06-00055 Attachment II RC-13-0054 Page 1 of 1 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT II LIST OF REGULATORY COMMITMENTS The following table identifies those actions committed to by SCE&G, Virgil C. Summer Nuclear Station in this document. Any other statements in this submittal are provided for information purposes and are not considered to be commitments. Please direct questions regarding these commitments to Mr. Bruce L Thompson, Manager, Nuclear Licensing, (803) 931-5042.
TDUE DATE [ EVENT Increase the scope of circuit protection modifications 2015 Update Generic Methodology Calculation, DC0780B-001 July 1, 2013