ML121800310
| ML121800310 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/28/2012 |
| From: | David Bice Entergy Nuclear Operations |
| To: | Kalyanam N Plant Licensing Branch IV |
| Kalyanam N, NRR/DLPM, 415-1480 | |
| Shared Package | |
| ML121800304 | List: |
| References | |
| TAC ME8282 | |
| Download: ML121800310 (20) | |
Text
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed S. Plant Modifications and Items to be Completed During Implementation Table S-1, Plant Modifications, provided below includes a description of the modifications along with the following information:
A problem statement, Risk ranking of the modification, An indication if the modification is currently included in the FPRA, Compensatory measure in place, and A risk-informed characterization of the modification and compensatory measure.
The following ranking legend should be used when reviewing the table:
High = Modification which would have an impact on FPRA and affect multiple Fire Areas.
Med = Modification which would have an impact on FPRA and affect individual Fire Areas, or include IN 92-18 modifications.
Low = Modification which would have no or insignificant impact on risk.
Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-1 Med 2 In Fire Area HH, a separation issue was ANO plans to relocate Yes Yes This modification is specifically (PRA) identified on the EFW valves interposing relays and affected credited from a PRA perspective.
2CV-1026-2 and 2CV-1076-2. During a cables associated with fire induced circuit failure the feedwater 2CV-1026-2 and 2CV-1076-2 Modification reduces the risk in valves may be impacted by a fire in Fire from Fire Area HH, Fire Zone Fire Area HH of a fire induced Zone 2096-M. 2096-M, to the adjacent room circuit failure for EFW valves in Fire Area G, Fire Zone 2CV-1026-2 and 2CV-1076-2 in LAR Source: 2098-C. Circuits for Fire Zone 2096-M.
Attachment C (NEI-04-02 Table B-3) 2CV-1026-2 and 2CV-1076-2 In accordance with station Section for EFW Valves 2CV-1026-2 are currently routed through directives, compensatory and 2CV-1076-2 in Fire Area HH Risk Fire Area G and no new measures per OP-1003.014 have Summary impacts will be generated by been established as appropriate.
this modification. to 2CAN031201 Page S-1
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-2 High 2 In Fire Area JJ, a separation issue was ANO plans to modify the Yes Yes This modification is specifically (PRA) identified that impacts the DC power circuits as described to credited from a PRA perspective cables control wiring on both trains. If a eliminate impacts in Fire and affects multiple fire areas.
fire event occurred, this could result in Area JJ associated with these the loss of equipment that would components. The modification limits the risk of a otherwise be available. Additional potential spurious operation and a considerations are potential spurious 2A-3, 2A-308, 2A-309, and loss of DC power to safety bus for operations at switchgear 2A-3 that may 2A-310 - The red train 125V switchgear 2A-3 due to a fire result in a loss of power to the safety DC panel 2D-23 that supplies induced circuit failure.
bus. control power for 2A-3 and 2B-5 is planned for relocation In accordance with station LAR Source: to Fire Area MM from Fire Area directives, compensatory Attachment C JJ. Control power cables are measures per OP-1003.014 have Switchgear/ (NEI-04-02 Table B-3) planned to be rerouted using been established as appropriate.
EFW Valves VFDR(s) embedded conduits from Fire Area MM to Fire Area II to 2A-3 JJ-04 avoid Fire Areas JJ and SS.
2A-308 JJ-04 This allows post-fire control of 2A-3 bus from the control 2A-309 JJ-04 room.
2CV-1036-2 JJ-01 2CV-1036 Auxiliary relays 2CV-1075-1 JJ-01 2CR1036A, B, C, and D are currently installed in MCC Attachment C (NEI-04-02 Table B-3) 2B-61 and are planned to be Fire Area JJ Risk Summary components: relocated to MCC 2B-63. This 2A-3, 2A-308, 2A-309, 2A-310, 2B-6, would eliminate cables that 2CV-1036-2, 2CV-1075-1, 2CV-4816, are routed through Fire and 2CV-4817. Area JJ associated with this valve. This eliminates a loss of 2CV-1036-2 due to a fire in Fire Area JJ and does not add an impact elsewhere.
(continued) to 2CAN031201 Page S-2
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-2 2CV-1075 The reroute of DC control power to bus 2A-3 and load-center 2B-5 listed above assures MCC 2B-53 remains available to power this valve. Control cables from 2C-17 to MCC 2B-53 are planned to be rerouted using an embedded conduit between Fire Area G and II to avoid Fire Areas JJ, SS, and TT.
New dedicated fuses are planned to be installed in 2C-17 for 2CV-1075-1 control relays so that failure of cables in scheme 2S113 will not impact 2CV-1075-1.
2B Cables are planned to be rerouted to control room panel 2C33-2 from 2B-6 using an embedded conduit between Fire Zone 2100-Z to the cable spreading room Fire Area G.
This eliminates an impact in Fire Area JJ.
2CV-4816 & 2CV-4817 - A reroute of cable 2I016N is planned by using embedded conduit C4080 that is located between Fire Area G (cable spreading room) to Fire Area EE-L. Cable 2I016N is also planned to be separately fused in panel C-09 to prevent failure due to a loss of cable 2I016P.
This eliminates circuit impacts in Fire Areas TT, JJ, and EE-U. to 2CAN031201 Page S-3
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-3 High 2 Fire induced circuit failure could impact ANO plans to install backup DC Yes Yes This modification is specifically (PRA) DC power cables feeding circuit control power to switchgear credited from a PRA perspective breakers at switchgear 2A-1, 2A-2, 2A-1, 2A-2, 2H-1 and 2H-2 with and affects multiple fire areas.
2H-1, and 2H-2. The failure of 2A-1 automatic transfer capability in and 2A-2 could prevent alignment to an Modification to install an alternate the event the normal DC offsite power source. The failure of DC power source reduces the risk control power source is lost.
2H-1 and 2H-2 could prevent tripping of a fire induced circuit failure to The new backup DC power the DC power cables feeding RCP the reactor coolant pumps (RCPs) from source will be located circuit breakers 2H-1 and 2H-2 the control room.
completely within Fire Area B-2 which could prevent tripping the LAR Source: in proximity to the switchgear RCPs from the control room.
Attachment C either on elevation 372 or (NEI-04-02 Table B-3) below at elevation 354. This In accordance with station Switchgear VFDR(s) eliminates impacts to directives, compensatory switchgear DC control power measures per OP-1003.014 have 2A-1 JJ-04 due to a fire in any other ANO-2 been established as appropriate.
2H-1 JJ-03, MM -04, SS-03 fire area and allows tripping of the RCPs in those areas.
2H-2 JJ-03, MM -04, SS-03 Inclusive in this modification Attachment C (NEI-04-02 Table B-3) is will be changes to the control globally credited in the performance power circuits for switchgear based Risk Summary for all fire areas. 2H-1 and 2H-2 to allow tripping the RCPs in a scenario where a fire originates internally to a switchgear cubicle. This design will prevent fire damage to a load cubicle from disabling the ability to trip the line breakers and remove power to the RCPs. The opposite scenario where fire damages the line breakers would not prevent the RCP load breakers from being tripped. This modification will require the line and load breakers be separately fused and fed as described:
(continued) to 2CAN031201 Page S-4
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-3 2H Internal DC control wiring jumpers will be removed to isolate the line and load cubicles. The DC control power for line breakers 2H-13, 2H-14, and 2H-15 will be isolated from the DC control power for the load breakers 2H-10, 2H-11, and 2H-12.
2H Internal DC control wiring jumpers will be removed to isolate the line and load cubicles. The DC control power for line breakers 2H-23, 2H-24, and 2H-25 will be isolated from the DC control power for the load breakers 2H-20, 2H-21, and 2H-22. to 2CAN031201 Page S-5
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-4 High 2 In Fire Area TT, a separation issue was ANO plans to modify the Yes Yes This modification is specifically (PRA) identified that impacts the power cables circuits as described to credited from a PRA perspective for EFW, chemical and volume control eliminate impacts in Fire and affects multiple fire areas.
system (CVCS), and service water Area TT associated with (SW) components 2B-5, 2CV-0789-1, The modification reduces the risk these components.
2CV-1036-2, 2CV-1075-1, 2CV-4816, of a fire induced circuit failure for 2CV-4817, and 2P-7B in the fire PRA 2CV-1036 Auxiliary relays EFW/CVCS/SW components and model. 2CR1036A, B, C, and D are power cables (2B-5, 2CV-0789-1, currently installed in MCC 2CV-1036-2, 2CV-1075-1, LAR Source: 2B-61 and are planned to be 2CV-4816, 2CV-4817, and 2P-7B)
EFW/ Attachment C relocated to MCC 2B-63. This in Fire Area TT.
CVCS/SW (NEI-04-02 Table B-3) would also eliminate cables Components VFDR(s) that are routed through Fire In accordance with station Area TT associated with this directives, compensatory 2CV-1036-2 TT-01 measures per OP-1003.014 have valve. This eliminates a loss 2CV-1075-1 TT-01 of 2CV-1036-2 due to a fire in been established as appropriate.
2P-7B TT-01 Fire Area TT.
2CV-0789-1 TT-01 2CV-1075 Cables for this valve between panels 2C-39 2CV-4816 TT-02 to 2C-17 that are currently 2CV-4817 TT-02 routed through Fire Area TT 2B-5 TT-03 are planned to be rerouted to remain exclusively in the cable Note: This modification is also spreading room. Control discussed in Item S1-2 for Fire cables from 2C-17 to MCC Area JJ. Modification resolves 2B-53 are planned to be impacts in both fire areas. rerouted using an embedded conduit between Fire Area G and II to avoid Fire Areas JJ, SS, and TT. New dedicated fuses are planned for installation in 2C-17 for 2CV-1075-1 control relays so that failure of cables in scheme 2S113 will not impact 2CV-1075-1.
(continued) to 2CAN031201 Page S-6
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-4 2P-7B - Cables for this pump 2B Cables for this load center between panels 2C-39 to between panels 2C-39 to 2C-33-1 2C-17 that are currently routed that are currently routed through through Fire Area TT are Fire Area TT are planned to be planned to be rerouted to rerouted to remain exclusively in remain exclusively in the cable the cable spreading room.
spreading room. New conduits are also planned to be installed.
2CV-0789 Cables for this valve between panels 2C-39 to 2C-17 that are currently routed through Fire Area TT are planned to be rerouted to remain exclusively in the cable spreading room. Control cables from 2C-17 to MCC 2B-53 are planned to be rerouted using an embedded conduit between Fire Area G and II to avoid Fire Areas JJ and SS.
2CV-4816 & 2CV-4817 - A reroute of cable 2I016N is planned by using embedded conduit C4080 that goes between Fire Area G (cable spreading room) to Fire Area EE-L. Cable 2I016N is also planned to be separately fused in panel C-09 to prevent failure due to a loss of cable 2I016P of cable. This eliminates circuit impacts in Fire Areas TT, JJ, and EE-U.
(continued) to 2CAN031201 Page S-7
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-4 2B Cables for this load center between panels 2C-39 to 2C-33-1 that are currently routed through Fire Area TT are planned to be rerouted to remain exclusively in the cable spreading room.
S1-5 High 2 In Fire Area SS, a fire induced circuit ANO plans to modify the Yes Yes This modification is specifically (PRA) failure could impact the DC power on circuits as described to credited from a PRA perspective both trains resulting in the loss of the eliminate impacts in Fire and affects multiple fire areas.
following components. Area SS associated with these components. The modification reduces the risk LAR Source: of a fire induced circuit failure that Attachment C 2A-3 and 2A-310 - The red could result in the loss of DC (NEI-04-02 Table B-3) train 125V DC panel 2D-23 power for both trains.
Switchgear VFDR(s) that supplies control power for In accordance with station 2A-3 SS-01 2A-3 and 2B-5 is planned to directives, compensatory be relocated from Fire Area JJ measures per OP-1003.014 have Attachment C (NEI-04-02 Table B-3) to Fire Area MM. Control been established as appropriate.
Fire Area SS Risk Summary power cables are planned to components 2A-4, 2A-409, 2B-6, be rerouted using embedded 2A-308, 2A-309, 2A-310, 2CV-0789-1, conduits from Fire Area MM to 2CV-1040-1, 2D-27, 2K-4A, 2P-16A, Fire Area II to avoid Fire Areas 2P-36A, 2PIS-0789-1, 2SV-0724-1, JJ and SS. This allows post-2SV-2809-1, 2SV-2810-1, and fire control of 2A-3 bus from 2SV-2811. the control room.
2A-4, 2A-409, & 2B Cables are planned to be rerouted to control room panel 2C33-2 from 2A-4 and 2B-6 using an embedded conduit between Fire Zone 2100-Z to the cable spreading room Fire Area G. This eliminates an impact in Fire Zone 2097-X and Fire Area JJ.
(continued) to 2CAN031201 Page S-8
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-5 The 125V DC control power from 2D-24 to 2A-4 is planned to be rerouted using a new conduit to avoid an impact against cables G2D2404A and B in Fire Zone 2097-X.
2CV-0789-1 & 2PIS-0789 The power cable for 2PIS-0789-1 (for 2CV-0789-1) is planned to be re-routed using an embedded conduit from Fire Area G to Fire Area II to avoid Fire Area SS.
2CV-1040 This valve is not directly impacted but is failed due to a loss of AC. The red train 125V DC panel 2D-23 that supplies control power for 2A-3 and 2B-5 is planned to be relocated from Fire Area JJ to Fire Area MM. Control power cables are planned to be routed using embedded conduits from Fire Area MM to Fire Area II to avoid Fire Areas JJ and SS. This assures 2CV-1040-1 will have a source of power and eliminates an impact in Fire Area SS.
(continued) to 2CAN031201 Page S-9
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-5 2A-308, 2A-309, 2D-27, 2K-4A, 2P-16A, 2P-36A, 2SV-0724-1, 2SV-2809-1, 2SV-2810-1, and 2SV-2811 - The cables associated with these components are planned to be re-routed to avoid Fire Area SS by using embedded conduits and as required the installation of a new raceway in Fire Area B-2 directly under Fire Area SS on elevation 372. The new raceway in Fire Area B-2 is planned to be installed above the vertical zone of influence for any postulated fire source. This eliminates impacts for 2A-308, 2A-309, 2D-27, 2K-4A, 2P-16A, 2P-36A, 2SV-0724-1, 2SV-2809-1, 2SV-2810-1, and 2SV-2811 in Fire Area SS.
S1-6 Med 2 Motor Operated Valves (MOVs) listed ANO plans to modify the No Yes The NPO modification reduces the (92-18) below will be modified to meet control circuit for 2CV-5038-1 risk of fire induced MOV circuit requirements per IN 92-18. The NPO to prevent spurious closure. failures (hot shorts, open circuits assessment determined that any one of This is planned to be similar to and short to ground). This MOV the RCS drop line valves can fail in a the inhibit circuit modification modification can prevent a non-closed and unrecoverable position on CV-1275 for ANO-1. recoverable position failure resulting in a loss of SDC. Procedural controls to secure resulting in the loss of shutdown power by opening breakers cooling.
LAR Source: are planned to be Attachment D implemented for 2CV-5084-1 In accordance with station MOVs (NEI-04-02 Table F-1) and 2CV-5086-2. directives, compensatory (IN 92-18) VFDR(s) measures per OP-1003.014 have been established as appropriate.
2CV-5038-1 NPO-RCS-SDC 2CV-5084-1 NPO-RCS-SDC 2CV-5086-2 NPO-RCS-SDC to 2CAN031201 Page S-10
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-7 Med 2 MOVs listed below will be modified to ANO plans to modify the control Yes Yes This modification is specifically (PRA) meet requirements per IN 92-18. The circuit for MOVs 2CV-1075-1, credited from a PRA perspective.
four EFW discharge valves and two 2CV-1076-2, 2CV-1036-2, EFW pump steam supply valves can 2CV-1039-1, 2CV-0340-2, and The modification reduces the risk fail in a closed and unrecoverable 2CV-0205-2 to prevent fire of fire induced MOV circuit failures position. induced spurious closing from (hot shorts, open circuits and short the main control room, Fire to ground). This MOV modification LAR Source: Area G. This will be can prevent a non-recoverable accomplished by separating the position failure.
Attachment C (NEI-04-02 Table B-3)
Section for EFW MOVs 2CV-1075-1, cable conductors, inclusive of In accordance with station 2CV-1076-2, 2CV-1036-2, 2CV-1039-1, internal panel wiring, that can directives, compensatory 2CV-0340-2, and 2CV-0205-2 in Fire cause spurious valve closing measures per OP-1003.014 have Area G Risk Summary and protecting them with been established as appropriate.
grounded metallic raceway and the use of grounded metallic barriers. This will prevent contact with potentially energized conductors from both intracable and intercable hot shorts.
MOV 2CV-1075-1 control cables R2B53J2C and R2B53J2N that enter panel 2C-17 or 2C-39 from floor penetrations have been identified as the cables of concern applicable to this modification.
MOV 2CV-1076-2 control cables G2D26C1D, G2D26C1E, and G2D26C1L that enter panel 2C-16 or 2C-40 from floor penetrations have been identified as the cables of concern applicable to this modification.
(continued) to 2CAN031201 Page S-11
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-7 MOV 2CV-1036-2 control cable G2B63H1E that enters panel 2C-40 from a floor penetration has been identified as the cable of concern applicable to this modification.
MOV 2CV-1039-1 control cable R2D27B2E that enters panel 2C-39 from a floor penetration has been identified as the cable of concern applicable to this modification.
MOV 2CV-0340-2 control cable G2D26B1E that enters panel 2C-16 from a floor penetration has been identified as the cable of concern applicable to this modification.
MOV 2CV-0205-2 control cables G2D26C2C, G2D26C2E, and G2D26C2F that enter panel 2C-16 or 2C-18 from floor penetrations have been identified as the cables of concern applicable to this modification. to 2CAN031201 Page S-12
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-8 Med 2 In Fire Area B-3, spurious opening of ANO plans to modify the control Yes Yes This modification is specifically (PRA) MOV 2CV-4698-1 pressurizer low circuit for 2CV-4698-1 to credited from a PRA perspective.
temperature - overpressure (LTOP) prevent fire induced spurious relief can result from a fire in motor opening in Fire Area B-3. This The modification in Fire Area B-3 control center (MCC) 2D-27. will be accomplished by to install flexible metallic conduit separating the cable protects the valve control cable in LAR Source: conductors, inclusive of internal MCC 2D-27 which reduces the risk panel wiring, that can cause of fire induced circuit failures (such Attachment C (NEI-04-02 Table B-3) as spurious opening). This Section for Fire Area B-3 Risk spurious opening and protecting the conductors with a grounded modification can prevent a non-Summary recoverable position failure.
metallic raceway and the use of grounded metallic barriers. This In accordance with station will prevent contact with directives, compensatory potentially energized measures per OP-1003.014 have conductors from both intracable been established as appropriate.
and intercable hot shorts.
Control cable R2D27A3J that enters MCC 2D-27 from a floor penetration has been identified as the cable of concern applicable to this modification.
S1-9 Med 2 In Fire Area G, spurious opening of ANO plans to modify the control Yes Yes This modification is specifically (PRA) valves 2CV-1002 (in cabinet 2C02), circuit for MOVs 2CV-1002, credited from a PRA perspective.
2CV-1052 (in cabinet 2C02), 2CV-1052, 2CV-0714-1, and 2CV-0714-1 (in cabinet 2C17), and 2CV-4698-1 to prevent fire The modification in Fire Area G to 2CV-4698-1 (in cabinet 2C09) can induced spurious opening in the install flexible metallic conduit result from a fire in the control room. main control room, Fire Area G. protects the valves control cable This will be accomplished by which reduces the risk of fire LAR Source: separating the cable induced circuit failures (such as conductors, inclusive of internal spurious opening). This Attachment C (NEI-04-02 Table B-3) modification can prevent a non-Section for MOVs 2CV-1002, panel wiring, that can cause spurious valve opening and recoverable position failure.
2CV-1052, 2CV-0714-1, and 2CV-4698-1 in Fire Area G Risk protecting the conductors with a In accordance with station Summary grounded metallic raceway and directives, compensatory the use of grounded metallic measures per OP-1003.014 have barriers. been established as appropriate.
(continued) to 2CAN031201 Page S-13
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-9 This will prevent contact with potentially energized conductors from both intracable and intercable hot shorts.
MOV 2CV-1002 control cable G2B63A3D that enters panel 2C-02 from a floor penetration has been identified as the cable of concern applicable to this modification.
MOV 2CV-1052 control cable R2B53D3D that enters panel 2C-02 from a floor penetration has been identified as the cable of concern applicable to this modification.
Valve 2CV-0714-1(2SV-0714-1) control cable R2S066E that enters panel 2C-17 from a floor penetration has been identified as the cable of concern applicable to this modification.
MOV 2CV-4698-1 control cable R2D27A3J that enters panel 2C-09 from a floor penetration has been identified as the cable of concern applicable to this modification. to 2CAN031201 Page S-14
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-10 Med 2 In Fire Area B-4 an incipient fire ANO plans to provide a Yes Yes This modification is specifically (PRA) detection system is not installed in modification in the CEDM credited from a PRA perspective.
control element drive mechanism room in Fire Area B-4 to install (CEDM) room panels 2C-70, 2C-71, incipient detection in cabinets The early warning fire detection 2C-72, 2C-73, and 2C-80. 2C-70, 2C-71, 2C-72, 2C-73, system modification in Fire 2C-80, and 2C-409. Area B-4 reduces the risk of a fire However an early warning fire detection induced circuit and equipment system in accordance with NFPA 72, Fire detection signal cable is failures that could result in the loss Fire Alarm Detection Code, is required planned to be routed from of CEDM room panels 2C-70, by the PRA in accordance with FRE each air sampling detector to 2C-71, 2C-72, 2C-73, 2C-80, and CALC-09-E-0008-05. the control room fire panel 2C-409.
2C-343-3.
LAR Source: In accordance with station directives, compensatory Attachment C (NEI-04-02 Table B-3) measures per OP-1003.014 have Section for CEDM Room Panels 2C-70, been established as appropriate.
2C-71, 2C-72, 2C-73, and 2C-80 in Fire Area B-4 Risk Summary S1-11 High 2 At ANO the availability of feedwater to ANO plans to install a new Yes Yes The AFW modification is (PRA) ANO-2 SGs was identified as an issue AFW pump in ANO-1 capable specifically credited from a PRA by PRA. of feeding one of the ANO-2 perspective to provide a reliable SGs. additional source of feedwater.
Also identified by PRA was ANOs inability to perform high risk and time The AFW would be designed The local control panel modification sensitive actions, such as control of to meet or exceed the flow is specifically credited from a PRA auxiliary feedwater (AFW), outside of requirements of ANO-2 perspective to provide an alternate the ANO-2 Control Room. Emergency Feedwater (EFW) means to perform required actions Pump 2P-7B (380 gpm @ outside the ANO-2 Control Room.
LAR Source: 1100 psig).
This modification reduces the risk Attachment C (NEI-04-02 Table B-3) The new pump, controls and of not being able to perform Fire Area G Risk Summary and motor operated valves would necessary operator actions to VFDR G-01 be designed to be installed in shutdown the plant, if either ANO-1. The preferred source Control Room cant be manned.
of suction for the new pump is planned to be from ANO-1. (continued)
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Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-11 The discharge piping is planned Also, the local control panel to be routed through the ANO-1 modification reduces the risk of and ANO-2 Turbine Buildings to availability issue with of feedwater ANO-2 Auxiliary Building supply to the ANO-2 SGs.
Rooms 2081 and 2084 for the tie-ins to the EFW System Manual actions are credited in fire piping. The AFW tie-ins are areas that contain redundant safe planned to discharge into the shutdown equipment. These ANO-2 EFW downstream of all actions have been demonstrated EFW injection valves to ensure feasible and are therefore a single area fire does not considered adequate disable AFW. compensatory measures until compliance can be achieved by The AFW pump would be transitioning to a 10CFR50.48(c) designed to have the capability licensing basis.
to be operated from the ANO-2 Control Room and locally in ANO-1. The design will ensure electrical isolation from Control Room functions to prevent a fire in the ANO-2 Control Room from affecting local control of AFW components.
The AFW pump and associated motor operated valves would be designed to be powered by diverse ANO-1 non-safety related power sources to prevent a single failure from disabling equipment operation.
The AFW pump would be designed to include controls and monitoring instrumentation to ensure proper water flow to the SGs. The local controls and monitoring instrumentation are planned to be located in ANO-1, powered from ANO-1 sources and have backup DC power. to 2CAN031201 Page S-16
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-12 Med 2 In Fire Area B-3, excessive ANO plans to modify the Yes No This modification supports a basic (PRA) temperatures have been identified in control wiring for fans 2VEF-63 assumption from a PRA Fire Zone 2091-BB following a loss of and 2VEF-64 to isolate the perspective.
ventilation. control room and allow the local controls to override a LAR Source: stop signal generated from Attachment C (NEI-04-02 Table B-3) within Fire Area G, either from Fire Area B-3 handswitch positioning or fire-induced circuit damage. This eliminates fire impacts in Fire Area G and assures either 2VEF-63 or 2VEF-64 will remain available except for a fire in Fire Area B-3, Fire Zone 2091-BB.
S1-13 Med 2 In Fire Area MM, excessive ANO plans to provide a Yes No This modification supports a basic (PRA) temperatures have been identified in modification to fire door assumption from a PRA Fire Zone 2099-W following a loss of DR 265 to allow normally open perspective.
ventilation. positioning with automatic closure features in the event of LAR Source: a fire. This allows natural Attachment C (NEI-04-02 Table B-3) circulation to prevent long term Fire Area MM room overheating impact on equipment located in Fire Zone 2099-W, West DC Equipment Room, by allowing an opening to Fire Zone 2109-U, Corridor, in Fire Area JJ. to 2CAN031201 Page S-17
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-14 Low C With regard to NFPA 50A, Gaseous ANO plans to provide a No No The subject hydrogen gas system (Code) Hydrogen Systems, code non- modification to move the bottle storage area is not credited compliance issues were identified in the hydrogen bottles and manifold by the PRA.
Hydrogen Gas Bottle Storage Room from the Hydrogen Gas Bottle related to inadequate vent piping and Storage Room to a concrete This modification will be completed room ventilation. The hydrogen storage slab located outside this room to meet NFPA 805 code room light switch was identified as not and open to atmosphere. This requirements.
meeting Article 501 for Class I, addresses hydrogen Division II locations of the National ventilation concerns and Electric Code (NEC). eliminates the need for electrical upgrades.
LAR Source:
Attachment A (NEI-04-02 Table B-1)
Section 3.3.7.1 to 2CAN031201 Page S-18
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-15 Med C NFPA 805 non-compliance issues were ANO plans to provide an Yes Yes This modification will be completed (PRA) encountered when smaller fire areas adequate-for-the-hazard to meet NFPA 805 code were defined such that multiple walls, evaluation and if necessary a requirements.
dampers, penetration seals, and doors modification to upgrade fire were credited and used in the PRA barrier walls, dampers, In accordance with station model as rated fire barriers in the NRC penetration seals, and doors directives, compensatory regulatory basis for NFPA 805. to rated barriers for those measures per OP-1003.014 have barriers credited for been established as appropriate.
Multiple walls and doors barriers will deterministic compliance and require upgrading to comply with subsequently credited in the NFPA 805. Fire PRA analysis.
LAR Source: These barriers have been Attachment A (NEI-04-02 Table B-1) previously identified as NRC Section 3.11.2 regulatory basis to ensure compliance with NFPA 805 and have compensatory measures established. The barriers to be addressed as identified by EC-1956 are 2005-2, 2005-3, 2067-4, 2082-3, 2091-1, 2091-2, 2091-3, 2091-4, 2107-4, 2110-2, 2110-4, 2110-7, 2112-2, 2112-8, 2112-10, 2133-5, 2133-6, 2147-8, 2148-4, 2148-5, 2149-5, 2152-2, 2154-2, 2154-3, 2154-5, 2158-10, 2224-2, 2224-3, 2228-10, 2239-4, 2239-5, 2256-4, 2256-5, 2256-6, 2256-8, 2134-1, and 2155-1. to 2CAN031201 Page S-19
Arkansas Nuclear One - Unit 2 Att. S - Plant Modifications and Items to be Completed Table S-1 Plant Modifications In Comp Item Rank Unit Problem Statement Proposed Modification Risk Informed Characterization FPRA Measure S1-16 Low C NFPA 10 non-compliance issues (such ANO plans to provide a No No The subject fire extinguishers are (Code) as incorrect number of fire modification to resolve the not credited in the FPRA.
extinguishers for travel distance, NFPA 10 code deficiencies incorrect type and size for the hazard identified in CALC-ANOC- This modification will be completed area) were identified with ANO portable FP-09-00009. to meet NFPA 805 code fire extinguishers. requirements.
In general, this modification LAR Source: would involve portable fire extinguisher physical Attachment A (NEI-04-02 Table B-1) relocation, substitution of Section 3.7 existing extinguishers, and documentation updates to reflect these plant changes.
The results will ensure the proper number of fire extinguishers to meet travel distance requirements in coverage areas, adequately sized fire extinguishers, and the correct type of extinguisher that is rated for the fire hazard in each area. to 2CAN031201 Page S-20