ML20114E262

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Final ASP Analysis - Shearon Harris (LER 400-02-004-09)
ML20114E262
Person / Time
Site: Harris Duke Energy icon.png
Issue date: 05/12/2020
From: Christopher Hunter
NRC/RES/DRA/PRB
To:
Hunter C (301) 415-1394
References
LER 400-02-004-09
Download: ML20114E262 (84)
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Text

Enclosure 1 Final Precursor Analysis Accident Sequence Precursor Program ---Office of Nuclear Regulatory Research Shearon Harris Unanalyzed Condition Due to Inadequate Separation of Associated Circuits.

Event Date: December 20, 2002 LER: 400/02-004 )CDP1 = 9x10-6 (thorough 1/18/2005 May 2, 2005 Condition Summary On December 20, 2002, inspection of the Harris Nuclear Plant (HNP) Safe Shutdown Analysis (SSA) identified that postulated fires could cause spurious actuation of certain valves . Valve actuation in the flowpath for the protected Charging/Safety Injection Pump (CSIP) could result in loss of the pump . Similarly, simultaneous spurious closure of multiple valves in the flowpaths to the Reactor Coolant Pump (RCP) seals could result in the loss of RCP seal cooling . HNP identified other postulated fires could cause spurious actuation of certain valves or components that could also result in the conditions described above, transfer of Refueling Water Storage Tank (RWST) inventory to the containment recirculation sump, transfer of some Reactor Coolant System (RCS) inventory to containment, inadvertent pressurizer spray, or could potentially impact indication used to monitor Reactor Coolant System pressure and level .

These additional postulated fires were discovered on January 29 and July 23, 2003 ; February 13, August 13, September 14 & 15, October 4, 20 , 26 & 29, 2004, and January 18, 2005.

Cause. The cause of these conditions is inadequate original Safe Shutdown Analysis of certain conductor-to-conductor interactions.

Other conditions, failures, and unavailable equipment. No other significant conditions, failures, or unavailable equipment occurred.

Recovery opportunities. No recovery opportunities are identified.

1 Since this condition did not involve an actual initiating event, the parameter of interest is the measure of the incremental increase between the conditional probability for the period in which the condition existed and the nominal probability for the same period but with the condition nonexistent and plant equipment available. This incremental increase or importance is determined by subtracting the CDP from the CCDP. This measure is used to assess the risk significance of hardware unavailabilities especially for those cases where the nominal CDP is high with respect to the incremental increase of the conditional probability caused by the hardware unavailability.

1

LER 400/02-004 Analysis Results

! Condition Importance ()CDP)

The condition importance for 8760 hours0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br /> is calculated to be:

Mean

)CDP 9x10-6 and is mainly due to consequential small LOCA events.

! Dominant sequences Fire Area Description Delta CDP  % Contribution 1-A-BAL-A RAB Balance South Area A 3.60E-06 38.5%

1-A-SWGRA Switchgear Room A 1.04E-06 11.1%

1-A-SWGRB Switchgear Room B 1.04E-06 11.1%

1-A-BAL-C RAB Balance South Area C 1.02E-06 10.9%

12-A-CR Main Control Room 6.62E-07 7.1%

1-A-BAL-B RAB Balance South Area B 6.37E-07 6.8%

1-A-EPA Electrical Penetration Area A 4.46E-07 4.8%

1-A-EPB Electrical Penetration Area B 4.46E-07 4.8%

1-C Containment Elevation 261' 2.22E-07 2.4%

1-A-CSRA Cable Spreading Room A 1.23E-07 1.3%

1-A-CSRB Cable Spreading room B 1.23E-07 1.3%

Sum = 9.36E-06 100.0%

These small LOCA events after the fire are caused by hot-short induced spurious operation of a PORV, or RCP seal leakage. Some of the fire-induced transient events modeled in the base case potentially become small LOCAs due to this failure mode induced by the condition.

The above condition was identified and reported through revision 6 of the LER (Reference 1).

Revision 7 of the LER (Reference 8) was issued after completion of the ASP analysis leading to the above reported results. This new LER added two more fire areas (1-A-ACP and 12-A-BAL) and additional affected components to the 12 existing areas. The additional condition reported in revision 7 of the LER is studied in Attachment D. The results do not significantly contribute to the already calculated condition importance and the insights gained by the analysis.

! Results tables

- The conditional probabilities of the sequences with the highest CCDPs are shown in Table 1.

Modeling Assumptions 2

LER 400/02-004

! Analysis type This is a plant condition only pertinent to fire events in twelve fire areas, which are listed above.

It is modeled as conditional assessment for fires in the areas of interest only. The time window for the condition is taken as a full year, 8760 hours0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br />.

The ASP analysis for this event is done using the process described below. Attachment B provides details.

1. Define the base and plant condition fire scenarios for each fire area. This includes calculation of scenario frequencies by considering fire area characteristics, identification of equipment affected (failed or spuriously operated) by each fire scenario and mapping these scenarios into associated SPAR model initiating events. This is done using the event trees found in the Attachment B.

The resulting fire scenarios are collected into bins, and are given in Table 1.

2. Calculate scenario CCDPs. For this purpose the SPAR model is used with the appropriate initiating event (e.g. TRANSIENT or SLOCA) caused by the fire, together with the failed equipment to calculate scenario CCDPs.
3. Calculate core damage probabilities for the base and the plant condition cases for the time window of interest. This includes calculating the CDFs for the new fire scenarios introduced by the condition, sum these frequencies and multiply the result by the time window for the condition.
4. Subtract the base case fire CDP from the plant condition fire CDP to obtain the condition importance.

The details of the quantification are given in Attachment B.

! Modeling assumptions Key modeling assumptions. The key modeling assumptions are listed below and discussed in detail in the following sections. These assumptions are important contributors to the overall results.

1. Use available information for fire areas from plant IPEEE.
2. Fire area 1-A-BAL-B has the most equipment susceptible to spurious operation (SO) concern generated by the condition. The potential SO issues generated for this area are also used across the board for all fire areas identified in the LER.

The components affected and the consequences postulated are given in Tables 2 and 3.

Other assumptions. Other assumptions are stated in the analysis as they are introduced.

3

LER 400/02-004

! Modifications to fault tree models No modifications to fault tree models are made.

! Basic event probability changes The basic event probability changes described below are applied to the SPAR transient and small LOCA event tree to quantify the conditional core damage probabilities calculated by setting the initiating event frequency of IE-TRANS or IE-SLOCA equal to 1.0. Once a CCDP is thus calculated, it is used for the corresponding sequence in each fire area.

For the base case, the trains damaged by fire are set to failure as follows:

ACP-BAC-LP-1ASA DIVISION 1A-SA AC POWER 6.9kV BUS FAILS set to true AFW-MDP-TM-1B AFW MDP 1B UNAVAILABLE DUE TO T&M set to true PPR-MOV-FC-117 PORV-RC-118 BLOCK VALVE CLOSED DURING POWER set to true Loss of AC bus A fails the CCW and HPI trains. The AFW failure is introduced since the SDP mentions possibility of AFW pump failure in one of the fire compartments, although it is not mentioned in the set of components in the LER. Also, the PORV block valve is set to closed to disable use of that PORV path for feed and bleed operations; this is conservative for cases where PORV SLOCA is postulated.

The RWST inventory diversion to the sump is modeled by increasing the failure probability of the operator action to switchover to recirculation (less time available due to spillage). The following operator actions are affected:

HPR-XHE-XM OPERATOR FAILS TO INITIATE HPR HPR-XHE-XM1 OPERATOR FAILS TO INITIATE HPR (dependent event)

LPR-XHE-XM OPERATOR FAILS TO INITIATE LPR The HEPs for these basic events are calculated in Attachment A.

Two new HEPs are introduced for operator failing to perform TRANSIENT or SMALL LOCA event procedures from the alternate control panel. The basic events for these are named ACP-XHE-TRANS and ACP-XHE-SLOCA. The HEPs are calculated in Attachment A.

Table B-3 shows the basic event probability changes that are implemented to generate the CCDPs for the eight cases defined.

! Sensitivity analyses None made.

! SPAR model updates No SPAR model updates are made.

4

LER 400/02-004 References

1. Progress Energy Licensee Event Report 2002-004-06, Unanalyzed Condition due to Inadequate Separation of Associated Circuits, 12/20/2004.
2. Shearon Harris NPP Unit 1 IPEEE Submittal, CP&L Company, June 1995.
3. Phase 3 SDP Analysis: Shearon Harris Nuclear Plant. US NRC Document ML0333807090.
4. Basis for Circuit Failure Probabilities, email from D. Friskin to J. Houghton 2/26/04.
5. NRC Inspection Report 50-400/02-11, January 31, 2003.
6. NRC Inspection Report 50-400/03-07, November 18, 2003.
7. ASP Guidelines for Fire-Induced Accident Sequence Precursor Analysis Methodology, Commercial Power Reactors, June 30, 2003, J. R. Houghton, E. B. Goldfeiz
8. Progress Energy Licensee Event Report 2002-004-07, Unanalyzed Condition due to Inadequate Separation of Associated Circuits, 01/18/2005.

5

LER 400/02-004 Table 1 Condition Importance (exposure time = 1 year)

BASE CONDITION Fire Area Description Initiating Ignition Scenario Area Scenario Area Delta  %

Event Frequency CDF CDF CDF CDF CDP Contributi on 1 1-A-BAL-B RAB Balance South Area B Transient/No SA 2.60E-03 6.68E-07 6.46E-07 2 1-A-BAL-B RAB Balance South Area B Transient/SA 2.60E-03 0.00E+00 6.68E-07 1.17E-08 1.31E-06 6.37E-07 6.8%

3 1-A-BAL-B RAB Balance South Area B Small LOCA 2.60E-03 0.00E+00 6.47E-07 4 1-A-BAL-C RAB Balance South Area C Transient/No SA 4.18E-03 1.07E-06 1.04E-06 5 1-A-BAL-C RAB Balance South Area C Transient/SA 4.18E-03 0.00E+00 1.07E-06 1.88E-08 2.10E-06 1.02E-06 10.9%

6 1-A-BAL-C RAB Balance South Area C Small LOCA 4.18E-03 0.00E+00 1.04E-06 7 1-A-EPA Electrical Penetration Area A Transient/No SA 2.64E-03 4.68E-07 4.53E-07 8 1-A-EPA Electrical Penetration Area A Transient/SA 2.64E-03 0.00E+00 4.68E-07 8.18E-09 9.15E-07 4.46E-07 4.8%

9 1-A-EPA Electrical Penetration Area A Small LOCA 2.64E-03 0.00E+00 4.54E-07 10 1-A-EPB Electrical Penetration Area B Transient/No SA 2.64E-03 4.68E-07 4.53E-07 11 1-A-EPB Electrical Penetration Area B Transient/SA 2.64E-03 0.00E+00 4.68E-07 8.18E-09 9.15E-07 4.46E-07 4.8%

12 1-A-EPB Electrical Penetration Area B Small LOCA 2.64E-03 0.00E+00 4.54E-07 13 1-A-CSRA Cable Spreading Room A Transient/No SA 5.00E-04 1.29E-07 1.24E-07 14 1-A-CSRA Cable Spreading Room A Transient/SA 5.00E-04 0.00E+00 1.29E-07 2.24E-09 2.51E-07 1.23E-07 1.3%

15 1-A-CSRA Cable Spreading Room A Small LOCA 5.00E-04 0.00E+00 1.25E-07 16 1-A-CSRB Cable Spreading room B Transient/No SA 5.00E-04 1.29E-07 1.24E-07 17 1-A-CSRB Cable Spreading room B Transient/SA 5.00E-04 0.00E+00 1.29E-07 2.24E-09 2.51E-07 1.23E-07 1.3%

18 1-A-CSRB Cable Spreading room B Small LOCA 5.00E-04 0.00E+00 1.25E-07 6

LER 400/02-004 19 12-A-CR Main Control Room Transient/No SA 9.50E-03 3.68E-05 3.57E-05 20 12-A-CR Main Control Room Transient/SA 9.50E-03 0.00E+00 3.68E-05 5.56E-07 3.74E-05 6.62E-07 7.1%

21 12-A-CR Main Control Room Small LOCA 9.50E-03 0.00E+00 1.17E-06 12-A-CRC1 Control Room Complex (included in MCR) 22 1-A-SWGRA Switchgear Room A Transient/No SA 4.24E-03 1.09E-06 1.05E-06 23 1-A-SWGRA Switchgear Room A Transient/SA 4.24E-03 0.00E+00 1.09E-06 1.90E-08 2.13E-06 1.04E-06 11.1%

24 1-A-SWGRA Switchgear Room A Small LOCA 4.24E-03 0.00E+00 1.06E-06 25 1-A-SWGRB Switchgear Room B Transient/No SA 4.24E-03 1.09E-06 1.05E-06 26 1-A-SWGRB Switchgear Room B Transient/SA 4.24E-03 0.00E+00 1.09E-06 1.90E-08 2.13E-06 1.04E-06 11.1%

27 1-A-SWGRB Switchgear Room B Small LOCA 4.24E-03 0.00E+00 1.06E-06 28 1-A-BAL-A RAB Balance South Area A Transient/No SA 1.47E-02 3.78E-06 3.65E-06 29 1-A-BAL-A RAB Balance South Area A Transient/SA 1.47E-02 0.00E+00 3.78E-06 6.60E-08 7.38E-06 3.60E-06 38.5%

30 1-A-BAL-A RAB Balance South Area A Small LOCA 1.47E-02 0.00E+00 3.66E-06 31 1-C Containment Elevation 261' Transient/No SA 1.90E-03 9.96E-09 3.41E-09 32 1-C Containment Elevation 261' Transient/SA 1.90E-03 0.00E+00 9.96E-09 3.44E-09 2.32E-07 2.22E-07 2.4%

33 1-C Containment Elevation 261' Small LOCA 1.90E-03 0.00E+00 2.25E-07 Sum = 4.57E-05 4.57E-05 5.50E-05 5.50E-05 9.36E-06 100%

Condition Importance (delta CDP) = 9.36E-06 7

Table 2 Table 2 Components involved in inadequate separation of associated circuits LER 2002-004-06 Matrix of Components by Fire Area Component 1-A-BAL-B 1-A-BAL-B 1-A-BAL-C 1-A-EPA 1-A-EPB 1-A-CSRA 1-A-CSRB 12-A-CR 12-A-CRC1 1-A-SWGRA 1-A-SWGRB 1-A-BAL-A 1-C (261' )

(261') (286') (286') (261') (261') (286' ) (286') (305') (305') (286') (286') (190', 216',

236', & 261')

SC Thermal barrier 1CC-207 1CC-207 1CC-207 1CC-207 1CC-207 SC Thermal barrier 1CC-208 1CC-208* 1CC-208 1CC-208 1CC-249 1CC-249 1CC-249 1CC-249 1CC-249 SC Thermal barrier 1CC-251 1CC-251* 1CC-251 1CC-251 SC Thermal barrier 1CC-252 1CC-252 1CC-252 1CC-252 SC CSIP damage 1CS-165 1CS-165 1CS-165 1CS-165 1CS-165 1CS-165 1CS-165 1CS-165 SC CSIP damage 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 1CS-166 SC CSIP damage 1CS-168 1CS-168 1CS-168 1CS-168 SC CSIP damage 1CS-169 1CS-169 1CS-169 1CS-170 1CS-170 1CS-170 1CS-171 1CS-171

$-MSA (B- RWST Inventory CT pump) 1CT-88 1CT-88

Table 2 Table 2 Components involved in inadequate separation of associated circuits LER 2002-004-06 Matrix of Components by Fire Area Component 1-A-BAL-B 1-A-BAL-B 1-A-BAL-C 1-A-EPA 1-A-EPB 1-A-CSRA 1-A-CSRB 12-A-CR 12-A-CRC1 1-A-SWGRA 1-A-SWGRB 1-A-BAL-A 1-C (261' )

(261') (286') (286') (261') (261') (286' ) (286') (305') (305') (286') (286') (190', 216',

236', & 261')

1RC-RCPB 1RC-RCPB 1RC-RCPB 1RC-RCPB 1RC-RCPB

  1. $-MSO $ RWST inventory; #

CSIP runout 1SI-3 1SI-3 1SI-3 1SI-3 1SI-3

$-MSO RWST inventory 1SI-300 1SI-300

$-MSO RWST inventory 1SI-301 1SI-301

$-MSO RWST inventory 1SI-310 1SI-310

$-MSO RWST inventory 1SI-311 1SI-311

$-MSO RWST inventory 1SI-322 1SI-322

$-MSO RWST inventory 1SI-323 1SI-323

  1. $-MSO $ RWST inventory; #

CSIP runout 1SI-86 1SI-86 1SI-86 1SI-86 1SI-86 RCS level/pressure PT-402 PT-402 RCS level/pressure PT-403 PT-403 SC Loss of AFW-A 1AF-19 1AF-19 Notes: *=MSA, *-MSO, *-MSC denotes the components associated with the same multiple spurious actuation concern

$-MSO, #-MSO SI Multiple simultaneous spurious openings transfer inventory from RWST to sump CT Single spurious opening transfers inventory from RWST to sump CS CSIP Spurious closing fails CSIP CC CCW Spurious closure fails CCW flow to RCP thermal barriers.

RC PT AF Table 1.1-1.xls 9 11/28/2005

LER 400/02-004 Table 3. Consequences by Fire Area SO RWST SC CCW SA CSIP SO PORV RCP SEAL (Thermal LOCA LOCA Barrier) (1) (2) 1 RAB Balance South Area B 1-A-BAL-B v v v v v 2 RAB Balance South Area C 1-A-BAL-C v v v v 3 Electrical Penetration Area A 1-A-EPA v v v v v 4 Electrical Penetration Area B 1-A-EPB v v 5 Cable Spreading Room A 1-A-CSRA v v v v v 6 Cable Spreading room B 1-A-CSRB v v v v 7 Main Control Room 12-A-CR v v v 8 Control Room Complex 12-A-CRC1 v v 9 Switchgear Room A 1-A-SWGRA v 10 Switchgear Room B 1-B-SWGRB v v v v 11 RAB Balance South Area A 1-A-BAL-A v v v 12 Containment Elev. 261' 1-C v Consequence Reactor Reactor Reactor Small LOCA Small LOCA Trip Trip Trip Notes:

1. From IPEEE
2. Multiple spurious openings that fail CCW and CSIP systems which lead to loss of RCP seal cooling, and thus potential RCP seal leakage.

10

LER 400/02-004 List of Attachments Attachment A: Human Error Calculations Attachment B: Analysis Details Attachment C Cutsets for Case-3: TR-Fire-RWST Fire-Induced Transient with RWST Spill Attachment D Cutsets for Case-4: SL-Fire-RWST Fire-Induced Small LOCA with RWST Spill 11

LER 400/02-004 Attachment A: Human Error Calculations I. HEPs due to RWST Spill In cases where the RWST inventory is spilled into the sump, and a LOCA occurs, the operators need to switchover to recirculation mode earlier than usual. This could affect the HEPs for Operator Fails to Initiate LPR or Operator Fails to Initiate HPR. The basic events for these HEPs are:

LPR-XHE-XM 0.001 Operator Fails to Initiate LPR HPR-XHE-XM 0.002 Operator Fails to Initiate HPR HPR-XHE-XM1 0.052 Operator Fails to Initiate HPR (dependent event)

These HEPs are requantified in this attachment.

If the RWST inventory is leaked into the containment sump due to SO of valve(s), the time window for the operators to perform switchover to recirculation is expected to be shortened.

The amount of shortened time can be bounded by the time to low RWST level signal during a Large LOCA event (maximum pumped flow being faster than gravity flow). Using the time available is equal to time required PSF penalty from the SPAR human error worksheet, the LPR and HPR HEPs are multiplied by a factor of 10. The other PSF factors were already reflected in the base HEPs.

The dependent event HEP is determined by the level of dependence and it is not affected much by the change of the base HEP. However, it is also multiplied by a factor of 2 to reflect an increase in failure probability.

Thus, the new HEPs used are:

LPR-XHE-XM 0.01 Operator Fails to Initiate LPR HPR-XHE-XM 0.02 Operator Fails to Initiate HPR HPR-XHE-XM1 0.1 Operator Fails to Initiate HPR (dependent event)

II. HEPs for Alternate Control Panel Operation Two new HEPs are introduced for operator failing to perform TRANSIENT or SMALL LOCA event procedures from the alternate control panel, when the fire causes evacuation of MCR.

The basic events for these are named ACP-XHE-TRANS and ACP-XHE-SLOCA. The HEPs are calculated as follows.

ACP-XHE-TRANS Operator fails to perform transient event procedures for decay heat removal from the alternate control panel (ACP), when the fire in the MCR causes evacuation of the MCR.

12

LER 400/02-004 The HEP is driven by action, since the diagnosis is forced by the evacuation of the MCR. The PSFs for stress (extreme) and ergonomics/HMI (poor) are assigned due to relocation of the operations to ACP. Other PSF factors are nominal. The HEP is calculated as:

HEP = 0.001

  • 5
  • 10 = 0.05.

The basic event probability is calculated as the sum of HEP plus the hardware failures. For example, for Case 3 (CCDP = 2.61e-04, from Table B-3):

ACP-XHE-TRANS = 0.05 + 2.61E-04 = 0.0503.

ACP-XHE-SLOCA Operator fails to perform small LOCA event procedures for decay heat removal and RCS inventory makeup from the alternate control panel, when the fire in the MCR causes evacuation of the MCR.

The HEP is driven by action, since the diagnosis is forced by the evacuation of the MCR. The PSFs for stress (extreme), ergonomics/HMI (poor), and complexity (high due to Small LOCA) are assigned due to relocation of the operations to ACP. Other PSF factors are nominal. The HEP is calculated as:

HEP = 0.001

  • 5
  • 10
  • 2 = 0.1.

The basic event probability is calculated as the sum of HEP plus the hardware failures. For example, for Case 4 (CCDP = 1.59E-02):

ACP-XHE-SLOCA = 0.1 + 1.59E-02 = 0.16.

13

LER 400/02-004 Attachment B: Analysis Details Shearon Harris Unit 1 Inadequate Separation of Associated Circuits Condition (December 20, 2002 - February 13, 2004) LER 400/02-004

1. The Condition of Concern On December 20, 2002, inspection of the Harris Nuclear Plant Safe Shutdown Analysis (SSA) identified that postulated fires in three fire areas could cause spurious closure of certain valves.

Spurious closure of valves in the flowpath for the protected Charging/Safety Injection Pump (CSIP) could result in loss of the CSIP in service at the time of the postulated fire. Similarly, simultaneous multiple spurious closures of valves in the flowpaths of water to the Reactor Coolant Pump (RCP) seals could result in loss of RCP seal cooling credited in the SSA. Upon discovery, interim compensatory actions were implemented.

On January 29, 2003, it was identified that simultaneous multiple spurious opening of certain valves could result in transferring of Refueling Water Storage Tank (RWST) inventory to the containment recirculation sump.

On July 23, 2003, it was identified that spurious opening of other certain valves could result in a similar transfer of RWST inventory.

On February 13, 2004, it was identified that multiple spurious actuations of certain valves in four additional areas could result in loss of the CSIP in service and in transferring of RWST inventory.

The previous four SSA fire areas identified included:

1. 1-A-BAL-B, located in the Reactor Auxiliary Building (RAB) Elevations 261' and 286
2. 1-A-BAL-C, located in the RAB Elevation 286
3. 1-A-EPA, located in the RAB Electrical Penetration Room "A" Elevation 261
4. 1-A-EPB, located in the RAB Electrical Penetration Room "B" Elevation 261 The discovery on February 13, 2003 identified the following four additional SSA fire areas:
5. 1-A-CSRA, located in the RAB Elevation 286
6. 1-A-CSRB, located in the RAB Elevation 286
7. 12-A-CR, located in the RAB Elevation 305
8. 12-A-CRC1, located in the RAB Elevation 305' Finally the discoveries on October 20 and October 29, 2004 identified the following four additional SSA fire areas :
9. 1-A-BAL-A, located in the RAB Elevations 190', 216', 236', and 261 '
10. 1-A-SWGRA, located in the RAB Elevation 286 '
11. 1-A-SWGRB, located in the RAB Elevation 286 '
12. 1-C, located in the Containment Elevation 261 '

14

LER 400/02-004 The cause of these conditions is inadequate original Safe Shutdown Analysis of certain conductor-to-conductor interactions.

Table 2 summarizes the components affected (either failed or spuriously activated) as described in the LER. Spurious primary PORV opening is also modeled in the IPEEE. The possible spurious opening-related concerns are summarized in Table 3. Note that a total loss of RCP seal cooling (failure of both CSIP and CCW) could also create a RCP seal LOCA if the operators do not trip the reactor in a timely manner. Even if the reactor is tripped in a timely manner, there is still a chance that a RCP seal LOCA would occur. This concern is also captured in Table 3.

15

LER 400/02-004

2. Major Assumptions
1. Use available information for fire areas from plant IPEEE.
2. Use the fire area 1-A-BAL-B damage for other fire areas also, since it has more potential damage than the others. This does not apply to the containment.
3. Process There is no SPAR model directly applicable to this condition. The ASP analysis for this event is performed by using the process described below.

- An event tree logic is created (see Figure B-1) to define scenarios for each fire area.

- SPAR models are used to calculate CCDPs for unique scenarios (event tree end states).

- The frequencies of event tree paths (sequences) are quantified for the base case and the current case (with the plant condition being analyzed).

- The condition importance is calculated for the appropriate exposure time, by summing over all sequence frequencies first for the base case, then for the current case; multiplying these sums by the exposure time and then taking the difference between the results.

The process consists of the following steps:

1. Identify fire frequencies for each of the fire areas;
2. Construct simple event tree logic to define fire scenarios; identify associated initiating events;
3. Calculate the various fire scenario frequencies, considering event characteristics;
4. Identify equipment affected by each fire scenario;
5. Use the appropriate initiating event (e.g. TRANSIENT or SLOCA) caused by the fire together with the failed equipment to calculate scenario CCDPs, using SPAR model;
6. Calculate the CDF for the base case and the case for the condition; calculate condition importance (delta CDP).
4. Fire Area Frequencies The fire area ignition frequencies are taken from the plant IPEEE submittal (Reference 2, Table 4-3 as shown in Table B-1), unless updated by a recent detailed evaluation, such as 1-A-BAL-B frequency in Reference 3.

16

LER 400/02-004 The frequency for the control room fires has been further evaluated in the IPEEE, and the value of 9.5E-03/yr has been calculated. This value is used. Note that the two areas, #7 and #8, are combined into one area for the analysis.

Electrical penetration area and switchgear room fire scenarios are further evaluated in the IPEEE submittal. The ignition frequencies are taken from these evaluations. The containment ignition frequency is taken from Reference /Finally, the 1-A-EPA frequency is also further evaluated in the IPEEE as 2.64E-03/yr. This value is used.

For the remaining areas, the IPEEE screening frequencies are used.

5. Define Scenarios The scenarios are defined in terms of I) whether the fire has passed incipient stage; ii) whether early auto or manual suppression has been successful; iii) whether a spurious component actuation (in this case, valve opening) occurs due to hot shorts (SO);

iv) given a SO, whether only a major system is affected (RWST, CCW or CSIP) without LOCA. Or a PORV or RCP seal LOCA occurs; The event tree of Figure B-1 depicts the logic used to define scenarios for each area. This event tree is used for each fire area, with the appropriate probabilities and frequency. The base case refers to the case where the spurious opening is not a concern (P-SO =0). However, equipment damage and a transient initiating event is still postulated as follows. The equipment damage is defined as follows:

Division A AC power and all equipment it supports is lost. This is modeled by setting the basic event ACP-BAC-LP-1ASA to failure. This failure does not apply to containment fires.

One pressurizer path is unavailable. This is modeled by setting PPR-MOV-FC-117 to failure.

SDP walkdown also indicates that the AFW MDP B may also be affected by fire. It is also set to failure by using the basic event AFW-MDP-TM-1B.

The spurious operation (SO) failures are postulated to lead to small LOCA, as modeled explicitly in the event tree if Figure B-1. Moreover, the SO failure(s) that could lead to RWST leakage to the sump are modeled as reduction in the time window of switchover to recirculation mode. The operator action failure probability for the switchover is affected. The HEP is calculated for LPR-XHE-XM, HPR-XHE-XM, and HPR-XHE-XM1 basic events in Attachment A.

The fire scenarios are generated for the fire areas defined in Table B-1, by using Figures B-2 through B-12. The end states for transient and small LOCA end states are collected for each 17

LER 400/02-004 fire area and are assigned the most limiting equipment damage. This leads to 33 fire scenarios defined in Table 1.

7. Success Criteria The same success criteria as in SPAR models are used for calculation of CCDPs.

For base fire case, no small LOCA is postulated due to spurious opening.

For the current case, small LOCA due to RCP seal failure or PORV opening is modeled, in addition to TRANSIENTS in case small LOCA does not occur.

6.1 Sequence Success criteria If the fire does not pass incipient stage, or early suppression occurs, then the sequence is not further modeled. The sequence where no SO occurs is treated as a transient; the sequence where SO occurs, but no LOCA occurs is also treated as a transient. The PORV and RCP seal LOCA sequences are treated as small LOCAs.

6.2 Event Tree Node Success Criteria Incipient stage and early suppression modeling is taken from the IPEEE or the phase 3 SDP, as appropriate. Occurrence of spurious opening is treated parametrically (see below). SO consequences are defined as either LOCA or loss of one or more systems/trains.

7. Data Fire Area Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Stage Suppression due to SO (5) due to SO LOCA due to SO (5) (3) (2), (5) 1 1-A-BAL-B 1 .05 (3) 0.3 0.3 0.063 0.3 2 1-A-BAL-C 1 .05 (4) 0.3 0.3 0.063 0.3 3 1-A-EPA 0.69 (1) .05 (4) 0.3 0.3 0.063 0.3 4 1-A-EPB 0.69 (6) .05 (4) 0.3 0.3 0.063 0.3 5 1-A-CSRA 1 .05 (4) 0.3 0.3 0.063 0.3 6 1-A-CSRB 1 .05 (4) 0.3 0.3 0.063 0.3 7/8 12-A-CR and 0.077 (1) .044 (1) 0.3 0.3 0.063 0.3 12-A-CRC1 9 1-A-SWGRA 1 .05 (4) 0.3 0.3 0.063 0.3 10 1-B-SWGRB 1 .05 (4) 0.3 0.3 0.063 0.3 11 1-A-BAL-A 1 .05 (4) 0.3 0.3 0.063 0.3 12 1-C 1 1 0.3 0.3 0.063 0.3 Notes:

1 From IPEEE 2 If two spurious openings already occurred in the scenario, then the third one is assumed to occur. In those 18

LER 400/02-004 sequences p=1.0 for this column.

3 For seal LOCA given RCP pumps stopped. Failure of operator action to stop RCP pumps is already modeled in SPAR as 0.001 and is small compared to this value.

Calculated as 0.3*0.21=0.063, where 0.3 is the SO of CCW and 0.21 is the SLOCA given loss of RCP seal cooling.

4 From SDP analysis 5 Reference 4 gives values ranging from .01 to .075 to 0.3 to 0.6. SDP analysis walkdown results indicate that some cables are protected by fire retardant wraps and enclosures; some trays and conduits are enclosed by fire retardant materials; others may not.

For the purposes of this analysis, the value of 0.3 is used for single or multiple spurious openings. This may be somewhat conservative, but definitely is not non-conservative, since the worst case thermoplastic (0.6).

6 Same as area 1A-EPA 7 No credit is given for suppression in containment 7.2 Changes in Existing Data:

For the base case, the trains damaged by fire are set to failure as follows:

ACP-BAC-LP-1ASA DIVISION 1A-SA AC POWER 6.9kV BUS FAILS set to failure AFW-MDP-TM-1B AFW MDP 1B UNAVAILABLE DUE TO T&M set to failure PPR-MOV-FC-117 PORV-RC-118 BLOCK VALVE CLOSED DURING POWER set to true Loss of AC bus A already fails the CCW and HPI trains. The AFW failure is introduced since the SDP mentions possibility of AFW pump failure in one of the fire compartments, although it is not mentioned in the set of components in the LER. Also, the PORV block valve is set to closed to disable use of that PORV path for feed and bleed operations; this is conservative for cases where PORV SLOCA is postulated.

For the condition case, both SLOCA is postulated, and also the RWST inventory diversion to the sump is modeled by increasing the failure probability of the operator action to switchover to recirculation (less time available due to spillage). The following operator actions are affected:

HPR-XHE-XM OPERATOR FAILS TO INITIATE HPR see below HPR-XHE-XM1 OPERATOR FAILS TO INITIATE HPR (dependent event) see below LPR-XHE-XM OPERATOR FAILS TO INITIATE LPR see below

8. Fault Trees No new fault trees are introduced.
9. Human Error In cases where the RWST inventory is spilled into the sump, and a LOCA occurs, the operators need to switchover to recirculation mode earlier than usual. This could affect the HEPs for Operator Fails to Initiate LPR or Operator Fails to Initiate HPR. The basic events for these HEPs are:

LPR-XHE-XM 0.001 Operator Fails to Initiate LPR HPR-XHE-XM 0.002 Operator Fails to Initiate HPR 19

LER 400/02-004 HPR-XHE-XM1 0.052 Operator Fails to Initiate HPR (dependent event)

These HEPs are requantified in Attachment A.

In the case where the running CSIP and CCW fail due to SO of valves, failure of the operators to trip the reactor coolant pumps in a timely manner is assumed to lead to RCP seal LOCA due to seal damage, as modeled in the SPAR by the basic event RCS-XHE-XM-TRIP, with A HEP of 0.001. This is used to estimate the RCP seal LOCA probability.

Two new HEPs are introduced for operator failing to perform TRANSIENT or SMALL LOCA event procedures from the alternate control panel. The basic events for these are named ACP-XHE-TRANS and ACP-XHE-SLOCA. The HEPs are calculated in Attachment A.

10. Calculate Scenario CCDPs To calculate the CCDPs for transient and SLOCA cases, the set of plant configurations in Table B-2 are defined. These plant configurations are compatible with the end states of the fire scenarios already defined.

CCDPs are calculated from SPAR models by setting either the SLOCA or TRANS initiating event frequency to 1.0, and all other initiating event frequencies equal to 0.0.

For all fire areas except the MCR and the containment, the equipment affected in area 1-A-BAL-B is used since it has the most impact. For MCR, the CCDP is dominated by HEPs at the alternate control panel, as discussed and quantified in the IPEEE.

TRANS-base and SLOCA-base Cases are obtained by running the base SPAR model (without any equipment failures) with IE-TRANS and IE-SLOCA set equal to 1 and other initiating event frequencies set equal to zero, respectively. These cases are made as reference cases and are not used in the fire scenarios. The other eight cases are generated by using the change sets shown in Table B-3.

11. Calculate Condition Importance To calculate the condition importance ()CDP) for SO events, first the base case CDP for a 8760 hour0.101 days <br />2.433 hours <br />0.0145 weeks <br />0.00333 months <br /> time frame for fire events in the areas of interest is quantified, without SO. The results are provided in Table B-4.

Then CCDP with the potential SO scenarios is calculated. The results are given in Table B-5.

Finally the difference between the two probabilities is taken to calculate )CDP for the condition.

The results are summarized in Table 1.

20

LER 400/02-004 Table B-1 Fire Area Frequencies Fire Area Description Screening Updated Freqs.

Frequency Frequency Used 1 1-A-BAL-B RAB Balance South Area B 1.03E-02 2.60E-03 (4) 2.60E-03 2 1-A-BAL-C RAB Balance South Area C 4.18E-03 4.18E-03 3 1-A-EPA Electrical Penetration Area A 2.93E-03 2.64E-03 (3) 2.64E-03 4 1-A-EPB Electrical Penetration Area B 1.49E-03 1.49E-03 5 1-A-CSRA Cable Spreading Room A 5.00E-04 5.00E-04 6 1-A-CSRB Cable Spreading Room B 3.85E-04 3.85E-04 7 12-A-CR Main Control Room 5.88E-03 9.50E-03 (2) 9.50E-03 8 12-A-CRC1 Computer Room/CR Complex 1.13E-02 (included in MCR) 1.13E-02 9 1-A-SWGRA Switchgear Room A 1.33E-02 4.24E-03 (3) 4.24E-03 10 1-B-SWGRB Switchgear Room B 1.26E-02 4.24E-03 11 1-A-BAL-A RAB Balance South Area A 3.53E-02 1.47E-02 (5) 1.47E-02 12 1-C Containment Elev. 261' none 1.9E-3 (6) 1.90E-03 Sum = 5.77E-02 Notes:

1 Frequencies are taken from the plant IPEEE submittal, unless updated by a recent detailed evaluation (see note 4).

The fire area screening frequencies are taken from Reference 2, Table 4-3. Updated frequencies are used, whenever available.

2 Control room fire frequency has been further evaluated in the IPEEE, and the value of 9.5E-03/yr has been calculated. This value is used. Note that the two areas, #7 and #8, are combined into one area for the analysis.

3 1-A-EPA frequency is also further evaluated in the IPEEE as 2.64E-03/yr. This value is used in the analysis.

1-A-SWGRA frequency is also further evaluated in the IPEEE IPEEE Table 4-5. This value is used in the analysis.

4 1-A-BAL-B frequency is further evaluated in an additional analysis performed by NRC (US NRC Document ML0333807090, proprietary).

5 Calculations from attachment B.

6 Reference 7.

7 For the remaining areas, the IPEEE screening frequencies are used. For symmetrical areas, such as EPA and EPB or CSRA and CSRB, higher of the two frequencies are used, if a pair had two different screening frequencies.

21

LER 400/02-004 Figure B-1 Fire Scenario Definitions Fire Past Incipient Early PORV LOCA CSIP Failure RCP Seal LOCA RWST Leak due to Scenario Initiating Additional Equipment Occurs in Stage Suppression due to SO due to SO SO Event Damage Due to SO (Note 1)

Fire Area XXXX 1 OK 2 TRANS Yes NO FAILURE 3 TRANS NO FAILURE FAILURE 4 TRANS RWST Leak Yes NO LOCA NO FAILURE 5 TRANS CSIP A NO LOCA FAILURE 6 TRANS RWST Leak, CSIP A FAILURE NO FAILURE 7 SLOCA CSIP A LOCA No FAILURE 8 SLOCA RWST Leak, CSIP A NO FAILURE 9 SLOCA NO FAILURE FAILURE 10 SLOCA RWST Leak LOCA NO FAILURE 11 SLOCA CSIP A FAILURE FAILURE 12 SLOCA RWST Leak, CSIP A Note 1 The base case fire scenario without spurious operation (SO) already postulates damage of equipment in the fire area.

SO = spurious operation of a valve (either opens or closes) due to hot short Table B-2 Definition of Cases 22

LER 400/02-004 CCDP SPAR Change Set Name CCDP /

CCDP-base 2.57E-04 CASE-1 TR-Base-Fire 565.03 1.57E-02 CASE-2 SL-Base-Fire 54.88 2.61E-04 CASE-3 TR-Base-Fire-RWST 573.81 1.59E-02 CASE-4 SL-Base-Fire-RWST 55.55 5.24E-06 CASE-5 TR-Base-Fire-Cont 11.51 2.93E-04 CASE-6 SL-Base-Fire-Cont 1.02 5.26E-06 CASE-7 TR-Base-Fire-RWST-Cont 11.55 3.78E-04 CASE-8 SL-Base-Fire-RWST-Cont 1.32 4.55E-07 TRANS-base 1 2.86E-04 SLOCA-base 1 Either IE-SLOCA or IE-TRANS set equal to 1.0 to calculate CCDP.

23

LER 400/02-004 Table B-3 Basic Event Changes Implemented by Change Sets Change / Event Calc. Type Prob / Freq Flag Set CASE-1 ACP-BAC-LP-1ASA T AFW-MDP-TM-1B T IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 +0.000E+000 IE-TRANS 1 1.000E+000 PPR-MOV-FC-117 T CASE-2 ACP-BAC-LP-1ASA T AFW-MDP-TM-1B T IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 24

LER 400/02-004 Change / Event Calc. Type Prob / Freq Flag Set IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 1.000E+000 IE-TRANS 1 +0.000E+000 PPR-MOV-FC-117 T CASE-3 ACP-BAC-LP-1ASA T AFW-MDP-TM-1B T HPR-XHE-XM 1 2.000E-002 HPR-XHE-XM1 1 1.000E-001 IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 +0.000E+000 IE-TRANS 1 1.000E+000 LPR-XHE-XM 1 1.000E-002 PPR-MOV-FC-117 T CASE-4 ACP-BAC-LP-1ASA T AFW-MDP-TM-1B T HPR-XHE-XM 1 2.000E-002 HPR-XHE-XM1 1 1.000E-001 IE-LLOCA 1 +0.000E+000 25

LER 400/02-004 Change / Event Calc. Type Prob / Freq Flag Set IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 1.000E+000 IE-TRANS 1 +0.000E+000 LPR-XHE-XM 1 1.000E-002 PPR-MOV-FC-117 T CASE-5 AFW-MDP-TM-1B T HPI-MDP-FR-1A 1 1.000E+000 IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 26

LER 400/02-004 Change / Event Calc. Type Prob / Freq Flag Set IE-SLOCA 1 +0.000E+000 IE-TRANS 1 1.000E+000 PPR-MOV-FC-117 T CASE-6 AFW-MDP-TM-1B T HPI-MDP-FR-1A 1 1.000E+000 IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 1.000E+000 IE-TRANS 1 +0.000E+000 PPR-MOV-FC-117 T CASE-7 AFW-MDP-TM-1B T HPI-MDP-FR-1A 1 1.000E+000 HPR-XHE-XM 1 2.000E-002 HPR-XHE-XM1 1 1.000E-001 IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 27

LER 400/02-004 Change / Event Calc. Type Prob / Freq Flag Set IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 +0.000E+000 IE-TRANS 1 1.000E+000 LPR-XHE-XM 1 1.000E-002 PPR-MOV-FC-117 T CASE-8 AFW-MDP-TM-1B T HPI-MDP-FR-1A 1 1.000E+000 HPR-XHE-XM 1 2.000E-002 HPR-XHE-XM1 1 1.000E-001 IE-LLOCA 1 +0.000E+000 IE-LOACB 1 +0.000E+000 IE-LOCCW 1 +0.000E+000 IE-LODCB 1 +0.000E+000 IE-LOIAS 1 +0.000E+000 IE-LOMFW 1 +0.000E+000 IE-LONSW 1 +0.000E+000 IE-LOOP 1 +0.000E+000 IE-MLOCA 1 +0.000E+000 IE-RHR-DIS-V 1 +0.000E+000 IE-RHR-HL-V 1 +0.000E+000 IE-RHR-SUC-V 1 +0.000E+000 IE-SGTR 1 +0.000E+000 IE-SI-CLDIS-V 1 +0.000E+000 IE-SI-HLDIS-V 1 +0.000E+000 IE-SLOCA 1 1.000E+000 IE-TRANS 1 +0.000E+000 LPR-XHE-XM 1 1.000E-002 PPR-MOV-FC-117 T 28

LER 400/02-004 Table B-4 Summary of Fire Area CDF Calculations Base Case (without SO)

Fire Area Description Initiating Event Ignition Scenario Scenario Scenario Area CDF  %

Frequenc Frequency CCDP CDF Contribu y tion 1 1-A-BAL-B RAB Balance South Area B Transient/No SA 2.60E-03 2.60E-03 2.57E-04 6.7E-07 2 1-A-BAL-B RAB Balance South Area B Transient/SA 2.60E-03 0.00E+00 2.61E-04 0.00E+00 6.68E-07 1.5%

3 1-A-BAL-B RAB Balance South Area B Small LOCA 2.60E-03 0.00E+00 1.59E-02 0.00E+00 4 1-A-BAL-C RAB Balance South Area C Transient/No SA 4.18E-03 4.18E-03 2.57E-04 1.07E-06 5 1-A-BAL-C RAB Balance South Area C Transient/SA 4.18E-03 0.00E+00 2.61E-04 0.00E+00 1.07E-06 2.4%

6 1-A-BAL-C RAB Balance South Area C Small LOCA 4.18E-03 0.00E+00 1.59E-02 0.00E+00 7 1-A-EPA Electrical Penetration Area A Transient/No SA 2.64E-03 1.82E-03 2.57E-04 4.68E-07 8 1-A-EPA Electrical Penetration Area A Transient/SA 2.64E-03 0.00E+00 2.61E-04 0.00E+00 4.68E-07 1.0%

9 1-A-EPA Electrical Penetration Area A Small LOCA 2.64E-03 0.00E+00 1.59E-02 0.00E+00 10 1-A-EPB Electrical Penetration Area B Transient/No SA 2.64E-03 1.82E-03 2.57E-04 4.68E-07 11 1-A-EPB Electrical Penetration Area B Transient/SA 2.64E-03 0.00E+00 2.61E-04 0.00E+00 4.68E-07 1.0%

12 1-A-EPB Electrical Penetration Area B Small LOCA 2.64E-03 0.00E+00 1.59E-02 0.00E+00 13 1-A-CSRA Cable Spreading Room A Transient/No SA 5.00E-04 5.00E-04 2.57E-04 1.29E-07 14 1-A-CSRA Cable Spreading Room A Transient/SA 5.00E-04 0.00E+00 2.61E-04 0.00E+00 1.29E-07 0.3%

15 1-A-CSRA Cable Spreading Room A Small LOCA 5.00E-04 0.00E+00 1.59E-02 0.00E+00 16 1-A-CSRB Cable Spreading room B Transient/No SA 5.00E-04 5.00E-04 2.57E-04 1.29E-07 17 1-A-CSRB Cable Spreading room B Transient/SA 5.00E-04 0.00E+00 2.61E-04 0.00E+00 1.29E-07 0.3%

18 1-A-CSRB Cable Spreading room B Small LOCA 5.00E-04 0.00E+00 1.59E-02 0.00E+00 19 12-A-CR Main Control Room Transient/No SA 9.50E-03 7.32E-04 5.03E-02 3.68E-05 20 12-A-CR Main Control Room Transient/SA 9.50E-03 0.00E+00 5.03E-02 0.00E+00 3.68E-05 80.5%

21 12-A-CR Main Control Room Small LOCA 9.50E-03 0.00E+00 1.16E-01 0.00E+00 12-A-CRC1 Control Room Complex (included in MCR) 29

LER 400/02-004 22 1-A- Switchgear Room A Transient/No SA 4.24E-03 4.24E-03 2.57E-04 1.09E-06 1.09E-06 2.4%

SWGRA 23 1-A- Switchgear Room A Transient/SA 4.24E-03 0.00E+00 2.61E-04 0.00E+00 SWGRA 24 1-A- Switchgear Room A Small LOCA 4.24E-03 0.00E+00 1.59E-02 0.00E+00 SWGRA 25 1-A- Switchgear Room B Transient/No SA 4.24E-03 4.24E-03 2.57E-04 1.09E-06 1.09E-06 2.4%

SWGRB 26 1-A- Switchgear Room B Transient/SA 4.24E-03 0.00E+00 2.61E-04 0.00E+00 SWGRB 27 1-A- Switchgear Room B Small LOCA 4.24E-03 0.00E+00 1.59E-02 0.00E+00 SWGRB 28 1-A-BAL-A RAB Balance South Area A Transient/No SA 1.47E-02 1.47E-02 2.57E-04 3.78E-06 3.78E-06 8.3%

29 1-A-BAL-A RAB Balance South Area A Transient/SA 1.47E-02 0.00E+00 2.61E-04 0.00E+00 30 1-A-BAL-A RAB Balance South Area A Small LOCA 1.47E-02 0.00E+00 1.59E-02 0.00E+00 31 1-C Containment Elevation 261' Transient/No SA 1.90E-03 1.90E-03 5.24E-06 9.96E-09 9.96E-09 0.0%

32 1-C Containment Elevation 261' Transient/SA 1.90E-03 0.00E+00 5.26E-06 0.00E+00 33 1-C Containment Elevation 261' Small LOCA 1.90E-03 0.00E+00 3.78E-04 0.00E+00 Sum = 3.5E-02 4.57E-05 4.57E-05 100.0%

30

LER 400/02-004 Table B-5 Summary of Fire Area CDF Calculations - Conditional Fire Area Description Initiating Event Ignition Scenario Scenario Scenario Area CDF  %

Frequenc Frequenc CCDP CDF Contribu y y tion 1 1-A-BAL-B RAB Balance South Area B Transient/No SA 2.60E-03 2.51E-03 2.57E-04 6.5E-07 2 1-A-BAL-B RAB Balance South Area B Transient/SA 2.60E-03 4.47E-05 2.61E-04 1.17E-08 1.31E-06 2.4%

3 1-A-BAL-B RAB Balance South Area B Small LOCA 2.60E-03 4.07E-05 1.59E-02 6.47E-07 4 1-A-BAL-C RAB Balance South Area C Transient/No SA 4.18E-03 4.04E-03 2.57E-04 1.04E-06 5 1-A-BAL-C RAB Balance South Area C Transient/SA 4.18E-03 7.18E-05 2.61E-04 1.88E-08 2.10E-06 3.8%

6 1-A-BAL-C RAB Balance South Area C Small LOCA 4.18E-03 6.55E-05 1.59E-02 1.04E-06 7 1-A-EPA Electrical Penetration Area A Transient/No SA 2.64E-03 1.76E-03 2.57E-04 4.53E-07 8 1-A-EPA Electrical Penetration Area A Transient/SA 2.64E-03 3.13E-05 2.61E-04 8.18E-09 9.15E-07 1.7%

9 1-A-EPA Electrical Penetration Area A Small LOCA 2.64E-03 2.85E-05 1.59E-02 4.54E-07 10 1-A-EPB Electrical Penetration Area B Transient/No SA 2.64E-03 1.76E-03 2.57E-04 4.53E-07 11 1-A-EPB Electrical Penetration Area B Transient/SA 2.64E-03 3.13E-05 2.61E-04 8.18E-09 9.15E-07 1.7%

12 1-A-EPB Electrical Penetration Area B Small LOCA 2.64E-03 2.85E-05 1.59E-02 4.54E-07 13 1-A-CSRA Cable Spreading Room A Transient/No SA 5.00E-04 4.84E-04 2.57E-04 1.24E-07 14 1-A-CSRA Cable Spreading Room A Transient/SA 5.00E-04 8.59E-06 2.61E-04 2.24E-09 2.51E-07 0.5%

15 1-A-CSRA Cable Spreading Room A Small LOCA 5.00E-04 7.83E-06 1.59E-02 1.25E-07 16 1-A-CSRB Cable Spreading room B Transient/No SA 5.00E-04 4.84E-04 2.57E-04 1.24E-07 17 1-A-CSRB Cable Spreading room B Transient/SA 5.00E-04 8.59E-06 2.61E-04 2.24E-09 2.51E-07 0.5%

18 1-A-CSRB Cable Spreading room B Small LOCA 5.00E-04 7.83E-06 1.59E-02 1.25E-07 19 12-A-CR Main Control Room Transient/No SA 9.50E-03 7.10E-04 5.03E-02 3.57E-05 20 12-A-CR Main Control Room Transient/SA 9.50E-03 1.11E-05 5.03E-02 5.56E-07 3.74E-05 68.0%

21 12-A-CR Main Control Room Small LOCA 9.50E-03 1.01E-05 1.16E-01 1.17E-06 12-A-CRC1 Control Room Complex (included in MCR) 31

LER 400/02-004 22 1-A-SWGRA Switchgear Room A Transient/No SA 4.24E-03 4.10E-03 2.57E-04 1.05E-06 23 1-A-SWGRA Switchgear Room A Transient/SA 4.24E-03 7.29E-05 2.61E-04 1.90E-08 2.13E-06 3.9%

24 1-A-SWGRA Switchgear Room A Small LOCA 4.24E-03 6.64E-05 1.59E-02 1.06E-06 25 1-A-SWGRB Switchgear Room B Transient/No SA 4.24E-03 4.10E-03 2.57E-04 1.05E-06 26 1-A-SWGRB Switchgear Room B Transient/SA 4.24E-03 7.29E-05 2.61E-04 1.90E-08 2.13E-06 3.9%

27 1-A-SWGRB Switchgear Room B Small LOCA 4.24E-03 6.64E-05 1.59E-02 1.06E-06 28 1-A-BAL-A RAB Balance South Area A Transient/No SA 1.47E-02 1.42E-02 2.57E-04 3.65E-06 29 1-A-BAL-A RAB Balance South Area A Transient/SA 1.47E-02 2.53E-04 2.61E-04 6.60E-08 7.38E-06 13.4%

30 1-A-BAL-A RAB Balance South Area A Small LOCA 1.47E-02 2.30E-04 1.59E-02 3.66E-06 31 1-C Containment Elevation 261' Transient/No SA 1.90E-03 6.52E-04 5.24E-06 3.41E-09 32 1-C Containment Elevation 261' Transient/SA 1.90E-03 6.53E-04 5.26E-06 3.44E-09 2.32E-07 0.4%

33 1-C Containment Elevation 261' Small LOCA 1.90E-03 5.95E-04 3.78E-04 2.25E-07 Sum = 3.5E-02 5.50E-05 5.50E-05 100.0%

32

1-A-BAL-B Figure B-2 Fires in RAB Balance South Area B (1-A-BAL-B) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-BAL-B Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 2.47E-03 0.95 2.60E-03 NO FAILURE 3 TRANS NO SO 1.30E-04 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 2.60E-03 2.57E-04 6.68E-07 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 2.60E-03 6.68E-07 CCDP-R2-0.xls 33 11/28/2005

1-A-BAL-C Figure B-3 Fires in RAB Balance South Area C (1-A-BAL-C) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-BAL-C Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 3.97E-03 0.95 4.18E-03 NO FAILURE 3 TRANS NO SO 2.09E-04 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 4.18E-03 2.57E-04 1.07E-06 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 4.18E-03 1.07E-06 CCDP-R2-0.xls 34 11/28/2005

1-A-EPA Figure B-4 Fires in Electrical penetration Area A (1-A-EPA) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-EPA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.00173052 0.95 2.64E-03 NO FAILURE 3 TRANS NO SO 9.11E-05 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 0.69 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 1.82E-03 2.57E-04 4.68E-07 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 1.82E-03 4.68E-07 CCDP-R2-0.xls 35 11/28/2005

1-A-EPB Figure B-5 Fires in Electrical penetration Area B (1-A-EPB) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-EPB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 1.73E-03 0.95 2.64E-03 NO FAILURE 3 TRANS NO SO 9.11E-05 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 0.69 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 1.82E-03 2.57E-04 4.68E-07 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 1.82E-03 4.68E-07 CCDP-R2-0.xls 36 11/28/2005

1-A-CSRA Figure B-6 Fires in Cable Spreading Room A (1-A-CSRA) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-CSRA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.000475 0.95 5.00E-04 NO FAILURE 3 TRANS NO SO 2.50E-05 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 5.00E-04 2.57E-04 1.29E-07 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 5.00E-04 1.29E-07 CCDP-R2-0.xls 37 11/28/2005

1-A-CSRB Figure B-7 Fires in Cable Spreading Room B (1-A-CSRB) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-CSRB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.75E-04 0.95 5.00E-04 NO FAILURE 3 TRANS NO SO 2.50E-05 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 5.00E-04 2.57E-04 1.29E-07 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 5.00E-04 1.29E-07 CCDP-R2-0.xls 38 11/28/2005

MCR Figure B-8 Control Room Fires (12-A-CR + 12-A-CRC1) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment MCR Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 6.99E-04 0.956 9.50E-03 NO FAILURE 3 TRANS NO SO 3.22E-05 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 0.077 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 1 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.044 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 7.32E-04 5.03E-02 3.68E-05 SUM TRANS/SO 0.00E+00 5.03E-02 0.00E+00 SUM SLOCA 0.00E+00 1.16E-01 0.00E+00 SUM ALL 7.32E-04 3.68E-05 CCDP-R2-0.xls 39 11/28/2005

1-A-SWGRA Figure B-9Fires in Switchgear Room A (1-A-SWGRA) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-SWGRA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.03E-03 0.95 4.24E-03 NO FAILURE 3 TRANS NO SO 2.12E-04 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 4.24E-03 2.57E-04 1.09E-06 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 4.24E-03 1.09E-06 CCDP-R2-0.xls 40 11/28/2005

1-A-SWGRB Figure B-10 Fires in Switvhgear Room B (1-A-SWGRB) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-SWGRB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.03E-03 0.95 4.24E-03 NO FAILURE 3 TRANS NO SO 2.12E-04 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 4.24E-03 2.57E-04 1.09E-06 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 4.24E-03 1.09E-06 CCDP-R2-0.xls 41 11/28/2005

1-A-BAL-A Figure B-11 Fires in RAB Balance South Area A (1-A-BAL-A) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-BAL-A Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 1.40E-02 0.95 1.47E-02 NO FAILURE 3 TRANS NO SO 7.35E-04 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 0.05 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 1.47E-02 2.57E-04 3.78E-06 SUM TRANS/SO 0.00E+00 2.61E-04 0.00E+00 SUM SLOCA 0.00E+00 1.59E-02 0.00E+00 SUM ALL 1.47E-02 3.78E-06 CCDP-R2-0.xls 42 11/28/2005

1-C Figure B-12 Fires in Containment Elevation 261' (1-C) - base Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-C Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.00E+00 0

1.90E-03 NO FAILURE 3 TRANS NO SO 1.90E-03 NO FAILURE 1 1 FAILURE 4 TRANS RWST Leak 0.00E+00 Yes 0 1 NO LOCA NO FAILURE 5 TRANS CSIP A 0.00E+00 1 NO LOCA 1 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 0.00E+00 FAILURE 0 0 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 0.00E+00 1 1 NO FAILURE 9 SLOCA 0.00E+00 NO FAILURE 1 1 FAILURE 10 SLOCA RWST Leak 0.00E+00 LOCA 0 0 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0 FAILURE 12 SLOCA RWST Leak, CSIP A 0.00E+00 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 1.90E-03 5.24E-06 9.96E-09 SUM TRANS/SO 0.00E+00 5.26E-06 0.00E+00 SUM SLOCA 0.00E+00 3.78E-04 0.00E+00 SUM ALL 1.90E-03 9.96E-09 CCDP-R2-0.xls 43 11/28/2005

1-A-BAL-B Figure B-2-c Fires in RAB Balance South Area B (1-A-BAL-B) - conditional Fire Occurs in 1-A- Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment BAL-B Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 2.47E-03 0.95 2.60E-03 NO FAILURE 3 TRANS NO SO 4.46E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 1.91E-05 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 1.79E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 7.67E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 1.72E-06 0.05 1 NO FAILURE 9 SLOCA 1.91E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 8.19E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 1.17E-05 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 2.51E-03 2.57E-04 6.46E-07 SUM TRANS/SO 4.47E-05 2.61E-04 1.17E-08 SUM SLOCA 4.07E-05 1.59E-02 6.47E-07 SUM ALL 2.60E-03 1.31E-06 CCDP-R2.xls 44 11/28/2005

1-A-BAL-C Figure B-3-c Fires in RAB Balance South Area C (1-A-BAL-C) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-BAL-C Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 3.97E-03 0.95 4.18E-03 NO FAILURE 3 TRANS NO SO 7.17E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 3.07E-05 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 2.88E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.23E-05 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 2.77E-06 0.05 1 NO FAILURE 9 SLOCA 3.07E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.32E-05 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 1.88E-05 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 4.04E-03 2.57E-04 1.04E-06 SUM TRANS/SO 7.18E-05 2.61E-04 1.88E-08 SUM SLOCA 6.55E-05 1.59E-02 1.04E-06 SUM ALL 4.18E-03 2.10E-06 CCDP-R2.xls 45 11/28/2005

1-A-EPA Figure B-4-c Fires in Electrical penetration Area A (1-A-EPA) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-EPA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.00173052 0.95 2.64E-03 NO FAILURE 3 TRANS NO SO 3.12E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 1.34E-05 Yes 0.3 0.69 NO LOCA NO FAILURE 5 TRANS CSIP A 1.25E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 5.38E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 1.20E-06 0.05 1 NO FAILURE 9 SLOCA 1.34E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 5.74E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 8.20E-06 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 1.76E-03 2.57E-04 4.53E-07 SUM TRANS/SO 3.13E-05 2.61E-04 8.18E-09 SUM SLOCA 2.85E-05 1.59E-02 4.54E-07 SUM ALL 1.82E-03 9.15E-07 CCDP-R2.xls 46 11/28/2005

1-A-EPB Figure B-5-c Fires in Electrical penetration Area B (1-A-EPB) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-EPB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 1.73E-03 0.95 2.64E-03 NO FAILURE 3 TRANS NO SO 3.12E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 1.34E-05 Yes 0.3 0.69 NO LOCA NO FAILURE 5 TRANS CSIP A 1.25E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 5.38E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 1.20E-06 0.05 1 NO FAILURE 9 SLOCA 1.34E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 5.74E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 8.20E-06 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 1.76E-03 2.57E-04 4.53E-07 SUM TRANS/SO 3.13E-05 2.61E-04 8.18E-09 SUM SLOCA 2.85E-05 1.59E-02 4.54E-07 SUM ALL 1.82E-03 9.15E-07 CCDP-R2.xls 47 11/28/2005

1-A-CSRA Figure B-6-c Fires in Cable Spreading Room A (1-A-CSRA) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-CSRA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.000475 0.95 5.00E-04 NO FAILURE 3 TRANS NO SO 8.58E-06 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 3.68E-06 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 3.44E-06 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.48E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 3.31E-07 0.05 1 NO FAILURE 9 SLOCA 3.68E-06 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.58E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 2.25E-06 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 4.84E-04 2.57E-04 1.24E-07 SUM TRANS/SO 8.59E-06 2.61E-04 2.24E-09 SUM SLOCA 7.83E-06 1.59E-02 1.25E-07 SUM ALL 5.00E-04 2.51E-07 CCDP-R2.xls 48 11/28/2005

1-A-CSRB Figure B-7-c Fires in Cable Spreading Room B (1-A-CSRB) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-CSRB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.75E-04 0.95 5.00E-04 NO FAILURE 3 TRANS NO SO 8.58E-06 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 3.68E-06 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 3.44E-06 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.48E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 3.31E-07 0.05 1 NO FAILURE 9 SLOCA 3.68E-06 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.58E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 2.25E-06 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 4.84E-04 2.57E-04 1.24E-07 SUM TRANS/SO 8.59E-06 2.61E-04 2.24E-09 SUM SLOCA 7.83E-06 1.59E-02 1.25E-07 SUM ALL 5.00E-04 2.51E-07 CCDP-R2.xls 49 11/28/2005

MCR Figure B-8-c Control Room Fires (12-A-CR + 12-A-CRC1) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment MCR Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 6.99E-04 0.956 9.50E-03 NO FAILURE 3 TRANS NO SO 1.10E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 4.73E-06 Yes 0.3 0.077 NO LOCA NO FAILURE 5 TRANS CSIP A 4.43E-06 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.90E-06 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 4.26E-07 0.044 1 NO FAILURE 9 SLOCA 4.73E-06 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 2.03E-06 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 2.90E-06 1

Scenario CCDPScenario CDF SUM TRANS/NO SO 7.10E-04 5.03E-02 3.57E-05 SUM TRANS/SO 1.11E-05 5.03E-02 5.56E-07 SUM SLOCA 1.01E-05 1.16E-01 1.17E-06 SUM ALL 7.32E-04 3.74E-05 CCDP-R2.xls 50 11/28/2005

1-A-SWGRA Figure B-9-c Fires in Switchgear Room A (1-A-SWGRA) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-SWGRA Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.03E-03 0.95 4.24E-03 NO FAILURE 3 TRANS NO SO 7.27E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 3.12E-05 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 2.92E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.25E-05 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 2.80E-06 0.05 1 NO FAILURE 9 SLOCA 3.12E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.34E-05 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 1.91E-05 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 4.10E-03 2.57E-04 1.05E-06 SUM TRANS/SO 7.29E-05 2.61E-04 1.90E-08 SUM SLOCA 6.64E-05 1.59E-02 1.06E-06 SUM ALL 4.24E-03 2.13E-06 CCDP-R2.xls 51 11/28/2005

1-A-SWGRB Figure B-10-c Fires in Switchgear Room B (1-A-SWGRB) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-SWGRB Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 4.03E-03 0.95 4.24E-03 NO FAILURE 3 TRANS NO SO 7.27E-05 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 3.12E-05 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 2.92E-05 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.25E-05 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 2.80E-06 0.05 1 NO FAILURE 9 SLOCA 3.12E-05 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.34E-05 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 1.91E-05 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 4.10E-03 2.57E-04 1.05E-06 SUM TRANS/SO 7.29E-05 2.61E-04 1.90E-08 SUM SLOCA 6.64E-05 1.59E-02 1.06E-06 SUM ALL 4.24E-03 2.13E-06 CCDP-R2.xls 52 11/28/2005

1-A-BAL-A Figure B-11-c Fires in RAB Balance South Area A (1-A-BAL-A) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-A-BAL-A Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 1.40E-02 0.95 1.47E-02 NO FAILURE 3 TRANS NO SO 2.52E-04 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 1.08E-04 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 1.01E-04 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 4.34E-05 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 9.72E-06 0.05 1 NO FAILURE 9 SLOCA 1.08E-04 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 4.63E-05 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 6.62E-05 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 1.42E-02 2.57E-04 3.65E-06 SUM TRANS/SO 2.53E-04 2.61E-04 6.60E-08 SUM SLOCA 2.30E-04 1.59E-02 3.66E-06 SUM ALL 1.47E-02 7.38E-06 CCDP-R2.xls 53 11/28/2005

1-C Figure B-12-c Fires in Containment Elevation 261' (1-C) - conditional Fire Occurs in Past Incipient Early PORV LOCA CSIP Failure RCP Seal RWST Leak Scenario Initiating Additional Equipment 1-C Stage Suppression due to SO due to SO LOCA due to SO Event Damage Due to SO (Note 1) 1 OK Yes 2 TRANS NO SO 0.00E+00 0

1.90E-03 NO FAILURE 3 TRANS NO SO 6.52E-04 NO FAILURE 0.7 0.7 FAILURE 4 TRANS RWST Leak 2.79E-04 Yes 0.3 1 NO LOCA NO FAILURE 5 TRANS CSIP A 2.62E-04 0.7 NO LOCA 0.7 0.937 FAILURE 6 TRANS RWST Leak, CSIP A 1.12E-04 FAILURE 0.3 0.3 NO FAILURE 7 SLOCA CSIP A 0.00E+00 LOCA 0 No 0.063 FAILURE 8 SLOCA RWST Leak, CSIP A 2.51E-05 1 1 NO FAILURE 9 SLOCA 2.79E-04 NO FAILURE 0.7 0.7 FAILURE 10 SLOCA RWST Leak 1.20E-04 LOCA 0.3 0.3 NO FAILURE 11 SLOCA CSIP A 0.00E+00 FAILURE 0 0.3 FAILURE 12 SLOCA RWST Leak, CSIP A 1.71E-04 1

Scenario CCDP Scenario CDF SUM TRANS/NO SO 6.52E-04 5.24E-06 3.41E-09 SUM TRANS/SO 6.53E-04 5.26E-06 3.44E-09 SUM SLOCA 5.95E-04 3.78E-04 2.25E-07 SUM ALL 1.90E-03 2.32E-07 CCDP-R2.xls 54 11/28/2005

Sequence Base Vs. Current Report by Current min cut Project: HARR_

Analysis RANDOM Attachment C Cutsets for Case-3: TR-Fire-RWST Event tree Sequence Curr Freq TRANS 04 2.294E-04 TRANS 11 7.351E-06 TRANS 06 6.077E-06 TRANS 18-20 5.214E-06 TRANS 07 3.673E-06 TRANS 17 2.722E-06 TRANS 16 2.693E-06 TRANS 13 2.532E-06 TRANS 14 1.552E-06 TOTALS = 2.612E-04 Cutsets removed during SUNSI review 2005/04/04 Page 1 17:22:23 Model Rev. 3.11 2004/12/22

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Sequence Base Vs. Current Report by Current min cut Project : HARR_3 Analysis: RANDOM Attachment D Cutsets for Case-4: SL-Fire-RWST Event tree Sequence Curr Freq SLOCA 03 1.355E-02 SLOCA 23 8.671E-04 SLOCA 13 3.151E-04 SLOCA 11 2.945E-04 SLOCA 22 2.526E-04 SLOCA 16 2.271E-04 SLOCA 10 1.459E-04 SLOCA 07 1.305E-04 SLOCA 05 5.049E-05 SLOCA 12 3.152E-05 SLOCA 24 5.214E-06 SLOCA 20 2.175E-06 SLOCA 18 8.415E-07 TOTALS = 1.587E-02 Cutsets removed during SUNSI review

Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Cutsets removed during SUNSI review Attachment D: ASP Analysis for Additional Plant Condition Reported in Revision 7 of the LER The plant condition as reported by the revision 6 of the LER (Reference 1) is already analyzed and its condition importance is calculated and reported in the main body of this ASP analysis for 12 fire areas. This attachment studies the condition importance of I) Two new fire areas reported by Revision 7 of the LER (Reference 8) as affected by the condition; namely areas 1-A-ACP (RAB elevation 286')

12-A-BAL (RAB Balance 286' and 305')

II) additional components that may be affected by the condition that is already studied in the main body of the ASP analysis (the twelve fire areas that are already analyzed).

I. Condition Importance of Areas 1-A-ACP and 12-A-BAL Fire Area 1-A-ACP There is a limited concern in this fire area, associated with potential spurious opening of SW isolation valve 1SW-39. This valve isolates the essential service water A train from the normal service water and directs the NSW flow to ESW train B through the open 1SW-40 valve. The LER points out that if ESW train B is in use, and 1SW-39 valve spuriously opens, the cooling capacity of the SW-B train would be diminished (like to 1DG-E003) since some of the flow will be diverted to ESW train A. The LER provides the following details:

For a postulated fire in SSA fire area 1-A-ACP (286' elevation), certain control cabling for the normal service water (NSW) supply valve (1 SW-39) to the "A" emergency service water (ESW) header and the "B" emergency diesel generator (EDG) (1 DG-E003) is not protected from spurious actuation in accordance with the requirements of NUREG 0800... . Therefore, this cabling is vulnerable to fire-induced hot shorts . The NSW system valve 1 SW-39 is required to close to provide isolation between NSW and ESW . A postulated fire in this area resulting in spurious actuation of these multiple components could result in a failure of the "B" EDG with the NSW supply valve (1SW-40) to the "B" ESW header subsequently open . With both NSW supply valves open, the ESW system flow would be split between the "A" and "B" trains . Thus, this diminished cooling capacity could affect the performance of equipment credited in the SSA and subsequently the ability to achieve and maintain safe shutdown.

The fire ignition frequency of this area is expected to be at the order of 0.0001 to 0.001 (like the frequencies of similar compartments studied in the IPEEE). There is no consequential SLOCA challenge due to the condition(e.g. no presurizer PORV or RCP seal leakage challenges). The condition importance due to a transient resulting from this plant condition is expected to be in the range of E-08 -E-07. Compared to the other 12 fire areas already studied with a potential SLOCA condition, the contribution of this area is deemed to be insignificant to affect the already calculated results and insights.

Fire Area 12-A-BAL The concern associated with this fire area is related to plant conditions at shutdown, when the RCS pressure is below 200 psig, as described in the LER:

For a postulated fire in SSA fire area 12-A-BAL certain control cabling for the 1 FB-8 (seal water injection filter backwash outlet valve), 1 NI-107 (seal water injection filter backwash nitrogen supply valve), and 1 PM-87 (seal water injection filter backwash primary water supply valve) is not protected from spurious actuation in accordance with the requirements of NUREG 0800, Attachment 1.... Therefore, this cabling is vulnerable to fire-induced hot shorts. If the plant has reached cold shutdown conditions and is depressurized below 200 psig with the charging system seal water injection inlet valve closed, then a postulated fire in this area resulting in spurious actuation of these multiple components could result in an inadvertent dilution or nitrogen injection to the RCS potentially reducing RCS inventory and natural circulation capability.

The screening ignition frequency for this area from IPEEE is 5.46E-03/year. The concern relates to shutdown and low RCS pressure RCS conditions, whereby the event development would be slow and recovery through valve closure is feasible and highly likely. The condition importance is not deemed to be high enough to affect the already calculated results for the 12 other fire areas studied with SLOCA conditions at power.

II. Impact of Additional Components in the Twelve Areas The new components added to the list of already potentially affected components (in revision 6 of the LER) are listed in Table D-1.

The following safety-related concerns are listed in the LER (Reference 8):

Potential safety consequence for a postulated fire in the two additional SSA fire areas 1-A-ACP (286' elevation) and 12-A-BAL (286' and 305' elevations) and the discoveries of components or combinations of components in the previously identified SSA fire areas that also results in spurious actuation of certain components identified on January 18, 2005 of this LER include:

  • Diminished cooling capacity potentially affecting the ability to achieve and maintain safe shutdown as credited by the SSA.
  • An inadvertent dilution or nitrogen injection to the RCS potentially reducing RCS inventory and natural circulation capability.
  • An unexpected RCS reduction in RCS pressure potentially affecting the ability to achieve and maintain safe shutdown as credited by the SSA.
  • Loss of mini-flow to the "A" CSIP, which is credited by the SSA for providing charging system flow.
  • A spurious opening of "A" AFW flow control valve could result in an inadvertent filling of the "A" steam generator (SG).
  • Loss of chilled water to the "A" switchgear room, loss of cooling fans to 236' RAB north hallway area, or loss of make-up capability or cooling water flow to certain chillers potentially affecting equipment credited in the SSA.
  • An unexpected diversion of chilled water to the non-running chiller could result in an inadvertent filling of the chiller surge tank and lifting of its associated relief valve.
  • Loss of auxiliary reservoir ESW traveling screens potentially affecting ESW cooling capability.
  • Simultaneous spurious opening of one or more SG power-operated relief valves (PORVs) and maloperation of its related SG PORV block valve could require manually closing the block valve.

The spurious opening of the secondary side relief valves is a new issue, not considered in the revision 6 analysis. However, this can lead to overcooling, not an immediate core damage threat, and can be remedied by closing the block valves. The consequential SLOCA scenarios previously studied (spurious valve actuations leading to PORV LOCA, or RCP seal leakage) already require SI injection for PRA success criteria.

SI injection would also address potential RCS inventory shrinkage during over-cooling. Thus, this concern is not of significance.

The other new issues mentioned are already bounded by the main scenarios which conservatively postulate the following failures or conditions in the twelve fire area scenarios studied in the main body of this ASP analysis:

loss of 1 train of AC; loss of charging pump; loss of one additional train of AFW:

small LOCA.

Many of the concerns mentioned in the LER revision 7 are not even in the scope of SPAR and other PRA models; these failures may not even affect the core damage scenarios.

Thus, the currently calculated condition importance for the LER revision 6 is deemed to be a conservative and acceptable representation of this plant condition, including the additional fire areas and components mentioned in Reference 7.

Table D-1 List of New Components Potentially Affected by the Plant Condition Heating Ventilation and Air conditioning: 1CH-115, -116, -125, -126, -279, -660 Secondary side relief valves: 1MS-58, -59, -60, -61, -62, -63 in Area 1-A-ACP 1SW-39 in Area 12-A-BAL 1FB-8, 1NI-107, 1PM-87 Miscellaneous 1RC-115, -116 1AF -49, -51 AH-6B-SB, AH-7B-SB 1SW-1171, -1204, -1208 1SC-E011, -E014

Shearon Harris LER-20020004 Revision 9 Impact of the Shearon Harris LER 2002-004-09 on the Previously Completed ASP Analysis

Background:

Shearon Harris ASP Analysis for the Unanalyzed Condition Due to Inadequate Separation of Associated Circuits, event date December 20, 2002 (thorough 1/18/2005) for the plant condition reported in LER 400/02-004-07, as performed on May 2, 2005 calculated the plant condition importance as CDP = 9E-06.

The ASP analysis was based on Revision 7 of the LER. On January 4, 2006, Revision 9 of the LER is noted.

Objective:

The objective of this note is the document the assessment of the impact of newly reported information in LER Revision 9 on the previous ASP analysis, which was based on Revision 7 of the LER.

Method:

Identify the new areas and components reported in LER Revision 9, compare the impact of this new information on the existing ASP model and determine if new calculations are needed or not.

I. Fire Areas:

Revisions 8 and 9 of the LER affect the following three fire areas, each of which was already modeled in the ASP analysis:

The discoveries on July 22 and August 4, 2005 included new components or combinations of components in the following two previously identified SSA fire areas:

1. 1-A-BAL-A, located in the RAB Elevation 236'
2. 1-A-BAL-B, located in the RAB Elevation 261' The discovery on August 30, 2005 included a new component in the following previously identified SSA fire area:
1. 1-A-CSRA, located in the RAB Elevation 286' II. Components In each revision of the LER, a matrix of affected components is provided. The components in these matrices (for the three fire areas identified above) are compared and it was determined that the following components were added to the matrix in Revision 9:

i) 1-A-BAL-B (261) : No new component, but EDG-A may spuriously actuate.

HARRIS~2.DOC 83 01/23/2006

Shearon Harris LER-20020004 Revision 9 (assume it fails the 4160 bus by doing so; otherwise no concern).

ii) 1-A-CSRA (286): AH-13-1B (air handler that cools the B switchgear room) iii) 1-A-BAL-A (236): 1CS-291 (manual opening of CSIP suction valve from RWST: smoke prevents operator action).

III. Potential consequences:

Loss of a whole division of safety-related equipment is already assumed in the ASP model (4160 bus A is assumed failed). Thus, components i) and ii) are covered in the model (ii) is for the B train; but A and B trains are symmetric with respect to PRA-modeled equipment).

Manual action to open MOV 1CS-291 is not credited in the SPAR. Thus, item iii) due to smoke effects is not consequential.

==

Conclusion:==

The currently available ASP model adequately estimates the importance of this plant condition. Revisions 8 and 9 of the LER introduce no new fire areas. The consequences of the few new components added to the plant condition can be subsumed in the consequences already modeled and quantified in the ASP analysis.

It is recommended that the current Asp analysis is kept as is, with this note added to account for the Revisions 8 and 9 of the LER.

1/4/2006 Selim Sancaktar HARRIS~2.DOC 84 01/23/2006

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