CNRO-2007-00015, Request for Alternative ANO2-R&R-004, Revision 1, Response to NRC Request for Additional Information: Difference between revisions

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{{#Wiki_filter:nteigy                                                                     Entergy Operations, Inc.
{{#Wiki_filter:nteigy Entergy Operations, Inc.
1340 Echelon Parkway Jackson, Mississippi 39213-8298 Tel: 601-368-5758 John F. McCann Director, Nuclear Safety & Licensing CNRO-2007-00028 August 6, 2007 U. S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555-0001
1340 Echelon Parkway Jackson, Mississippi 39213-8298 Tel: 601-368-5758 John F. McCann Director, Nuclear Safety & Licensing CNRO-2007-00028 August 6, 2007 U. S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555-0001


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==Dear Sir or Madam:==
==Dear Sir or Madam:==
Per the referenced letter, Entergy Operations, Inc. (Entergy) submitted Request for Alternative ANO2-R&R-004, Rev. 1, which requested the NRC staff's authorization to implement a risk-informed safety classification (RISC) process for repair/replacement activities in Class 2 and 3 moderate energy systems at Arkansas Nuclear One, Unit 2 (ANO-2). In its review of the request, the NRC staff requested that Entergy provide a test case, or example, that demonstrates the RISC process. Entergy is providing the requested example in the enclosure to this letter to support the staffs review. Following approval of ANO2-R&R-004, Rev. 1, any specific application of this process to a plant system Would be initiated and controlled in accordance with appropriate engineering programs.
Per the referenced letter, Entergy Operations, Inc. (Entergy) submitted Request for Alternative ANO2-R&R-004, Rev. 1, which requested the NRC staff's authorization to implement a risk-informed safety classification (RISC) process for repair/replacement activities in Class 2 and 3 moderate energy systems at Arkansas Nuclear One, Unit 2 (ANO-2). In its review of the request, the NRC staff requested that Entergy provide a test case, or example, that demonstrates the RISC process. Entergy is providing the requested example in the enclosure to this letter to support the staffs review. Following approval of ANO2-R&R-004, Rev. 1, any specific application of this process to a plant system Would be initiated and controlled in accordance with appropriate engineering programs.
In addition to submitting the requested example, Entergy revises the need date for ANO2-R&R-004, Rev. 1 to April 17, 2008. Should you have any questions regarding this submittal, please contact Guy Davant at (601) 368-5756.
In addition to submitting the requested example, Entergy revises the need date for ANO2-R&R-004, Rev. 1 to April 17, 2008. Should you have any questions regarding this submittal, please contact Guy Davant at (601) 368-5756.
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Application of Risk-Informed Safety Classification Process for Repair/Replacement Activities in Class 2 and 3 Moderate Energy Systems kL)6ý
Application of Risk-Informed Safety Classification Process for Repair/Replacement Activities in Class 2 and 3 Moderate Energy Systems kL)6ý


CNRO-2007-00028 Page 2 of 2 cc:   Mr. J. S. Forbes (ECH)
CNRO-2007-00028 Page 2 of 2 cc:
Mr. J. S. Forbes (ECH)
Mr. 0. Limpias (WPO)
Mr. 0. Limpias (WPO)
Mr. T. G. Mitchell (ANO)
Mr. T. G. Mitchell (ANO)
Dr. Bruce S. Mallett U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 U. S. Nuclear Regulatory Commission Attn: Mr. Alan Wang .
Dr. Bruce S. Mallett U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 U. S. Nuclear Regulatory Commission Attn: Mr. Alan Wang MS O-7D1 Washington, DC 20555-0001 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847
MS O-7D1 Washington, DC 20555-0001 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847


CNRO-2007-00028 bcc:       Mr. W. B. Abraham (G-ADM2-LIC)
CNRO-2007-00028 bcc:
Mr. W. B. Abraham (G-ADM2-LIC)
Mr. C. A. Bottemiller (G-ADM2-LIC)
Mr. C. A. Bottemiller (G-ADM2-LIC)
Mr. W. B. Brice (M-ECH-521)
Mr. W. B. Brice (M-ECH-521)
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ENCLOSURE CNRO-2007-00028 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY SYSTEMS
ENCLOSURE CNRO-2007-00028 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY SYSTEMS


Enclosure to CNRO-2007-00028 Page lof40 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY PIPING SYSTEMS I. OVERVIEW This document package contains an example application of the risk-informed safety classification (RISC) process to be applied to repair/replacement activities in Class 2 and 3 moderate energy piping systems. This process was submitted to the NRC staff for approval by Entergy Operations, Inc. (Entergy) as Request for Alternative ANO2-R&R-004, Rev. i via letter CNRO-2007-00015 dated April 17, 2007. The RISC process was developed by EPRI and is founded upon the EPRI risk-informed inservice inspection (RI-ISI) evaluation procedure (EPRI TR-1 06706, Rev B-A).
Enclosure to CNRO-2007-00028 Page lof40 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY PIPING SYSTEMS I.
OVERVIEW This document package contains an example application of the risk-informed safety classification (RISC) process to be applied to repair/replacement activities in Class 2 and 3 moderate energy piping systems. This process was submitted to the NRC staff for approval by Entergy Operations, Inc. (Entergy) as Request for Alternative ANO2-R&R-004, Rev. i via letter CNRO-2007-00015 dated April 17, 2007. The RISC process was developed by EPRI and is founded upon the EPRI risk-informed inservice inspection (RI-ISI) evaluation procedure (EPRI TR-1 06706, Rev B-A).
The NRC granted Arkansas Nuclear One, Unit 2 (ANO-2) approval to implement what, is known as a full-scope RI-ISI program [i.e., Class 1, 2, and some 3 / non-nuclear safety (NNS) piping] using the EPRI RI-ISI procedure.' As such, the vast majority of the information necessary to support the repair/replacement relief request already exists.
The NRC granted Arkansas Nuclear One, Unit 2 (ANO-2) approval to implement what, is known as a full-scope RI-ISI program [i.e., Class 1, 2, and some 3 / non-nuclear safety (NNS) piping] using the EPRI RI-ISI procedure.' As such, the vast majority of the information necessary to support the repair/replacement relief request already exists.
The final piece of the process is what is termed "the additional considerations', which consists of a series of questions that supplement the consequence evaluation that was previously developed as part of the RI-ISI application. These additional considerations were addressed by developing draft responses and conducting an interdisciplinary review during a-meeting held on July 12, 2007 at the ANO site.
The final piece of the process is what is termed "the additional considerations', which consists of a series of questions that supplement the consequence evaluation that was previously developed as part of the RI-ISI application. These additional considerations were addressed by developing draft responses and conducting an interdisciplinary review during a-meeting held on July 12, 2007 at the ANO site.
II. APPLICATION As requested by the NRC, Entergy has developed this example application of the RISC process by applying it to the Containment Spray System (CSS). 2 The CSS evaluation does not credit the Containment Cooling System (CCS), which provides another means of containment heat removal independent of CSS. As such, the consequence rank identified herein is conservative for a numberof segments. However, the rank of high-ranked segments would not change since failure of these segments typically results in a loss of Emergency Core Cooling Systems (ECCS) and/or a containment bypass potential.
II.
APPLICATION As requested by the NRC, Entergy has developed this example application of the RISC process by applying it to the Containment Spray System (CSS).2 The CSS evaluation does not credit the Containment Cooling System (CCS), which provides another means of containment heat removal independent of CSS. As such, the consequence rank identified herein is conservative for a numberof segments. However, the rank of high-ranked segments would not change since failure of these segments typically results in a loss of Emergency Core Cooling Systems (ECCS) and/or a containment bypass potential.
Table 1, below, is taken from the RI-ISI evaluation for CSS with one modification being to ID
Table 1, below, is taken from the RI-ISI evaluation for CSS with one modification being to ID
#s CSS-C-17A and -17B, which no longer credit CCS as available backup. 3 Figures 1 and 2, also taken from the RI-ISI evaluation, provide simplified piping diagrams of CSS.
#s CSS-C-17A and -17B, which no longer credit CCS as available backup. 3 Figures 1 and 2, also taken from the RI-ISI evaluation, provide simplified piping diagrams of CSS.
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3 Entergy submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.
3 Entergy submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.


Enclosure to CNRO-2007-00028 Page 2 of 40 TABLE 1 CSS Consecluence Assessment Summary
Enclosure to CNRO-2007-00028 Page 2 of 40 TABLE 1 CSS Consecluence Assessment Summary Decito
  .. ID * ": 'Descripion       - -    ^ .,. "  Configum-tior i     Initiator .Ioaion'*.-
-Spatial Cnguain Itaor slton
a-      :    ,.,,;*.      -    Backup     Containment ',     Tm       N t l=:*":     ;
-System.
Decito    -Spatial      Cnguain            Itaor        slton    -System.                  AalbeEpsr                              TbeUed        Rank I -Location.                                                         IsP t,         Impacts                 ckp     Cnamet             Time     (Note 1 Trains CSS-C-01     Common RWT             Outside       Demand         Assumed         No       CSS, HPSI,                 0       Unaffected     between     2-2       HIGH suction outside                                           M                           LPSI                                               test CSS-C-02     Common RWT                                           Assumed         No       CSS, HPSI,                           Unaffected     between     2-2       HIGH suction inside           2040       Demand             M                           LPSI                                               test CSS-C-03A     RWT suction A             2040       Demand         Assumed     2CV-5630       ECCS A or           1 (ECCS B or     Unaffected     between     2-2       MEDIUM in 2040                                             M                       all ECCS             isolation)                       test CSS-C-03B     RWT suction B                                         Assumed     2CV-5631       all ECCS &                           Unaffected     between     2-2       HIGH in 2040             2040       Demand             M                           CSS                                               test CSS-C-04A     RWT suction A                                         Assumed     2CV-5630       ECCS A or           1 (ECCS B or     Unaffected     between     2-2       MEDIUM inscin              2014       Demand             M                       all ECCS             isolation)                       test CSS-C-04B     RWT-suction               2007       Demand in 2007 B                                        Assumed M      2CV-5631       ECCS all ECCS B o. 1 (ECCS   A or isolation)    Unaffected     between test    2-2       MEDIUM CSS-C-05     RWT suction B             2006       Demand         Assumed     2CV-5631       ECCS B or           1 (ECCS A or     Unaffected     between     2-2       MEDIUM in 2006                             eM                                         all ECCS             isolation)                       test.
AalbeEpsr TbeUed Rank ID *  
CSS-C-06A     Sump suction                                         Assumed     2CV-5647       ECCS Ao.r           1 (ECCS B or   Bypass if Isol   all year   2-2       HIGH A in 2014                                             M                       all ECCS             isolation)       fails CSS-C-06B     Sump suction B in 2007             2007       Demand Assumed M
'Descripion  
ECCS all ECCS B 2r    1 (ECCS    A or isolation)       failsif Isol Bypass 2P-35A                                           Assumed   Trip pump &     ECCS A or           1 (ECCS B or                     between     2-2       MEDIUM CSS-C-07A     discharge to             2014       Demand             M       2CV-5630         all ECCS             isolation)   Unaffected         test 2E35A 2P35B                                           Assumed   Trip pump &     ECCS B or           1 (ECCS A or                     between CSS-C-07B     discharge to             2007       Demand                                                   --                    Unaffected         t2-2               MEDIUM 2E35B                                               M       2CV-5631         all ECCS             isolation)                       test 2P-3A           miiAsume      Trp pup &between CSS-C-08A     2P-35A mini             2014       Demand         Assumed   Trip pump &         CSS A             1 (CSS B . Unaffected     between     2-2       MEDIUM flow                                               M       2CV-5630                                                               test CSS-C-08B       2P35B mini                                         Assumed   Trip pump &         CSS B             1 (CSS Al)     Unaffected     between       22       MDU flow               2007       Demand             M       2CV-5631                                                               test     22       MDU
^.,.
Configum-tior i Initiator a-
.Ioaion'*.-
Backup Containment ',
Tm N t l=:*":
I  
-Location.
IsP t, Impacts ckp Cnamet Time (Note 1 Trains CSS-C-01 Common RWT Outside Demand Assumed No CSS, HPSI, 0
Unaffected between 2-2 HIGH suction outside M
LPSI test CSS-C-02 Common RWT Assumed No CSS, HPSI, Unaffected between 2-2 HIGH suction inside 2040 Demand M
LPSI test CSS-C-03A RWT suction A 2040 Demand Assumed 2CV-5630 ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM in 2040 M
all ECCS isolation) test CSS-C-03B RWT suction B Assumed 2CV-5631 all ECCS &
Unaffected between 2-2 HIGH in 2040 2040 Demand M
CSS test CSS-C-04A RWT suction A Assumed 2CV-5630 ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM in scin 2014 Demand M
all ECCS isolation) test CSS-C-04B RWT-suction B 2007 Demand Assumed 2CV-5631 ECCS B o.
1 (ECCS A or Unaffected between 2-2 MEDIUM in 2007 M
all ECCS isolation) test CSS-C-05 RWT suction B 2006 Demand Assumed 2CV-5631 ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM in 2006 eM all ECCS isolation) test.
CSS-C-06A Sump suction Assumed 2CV-5647 ECCS Ao.r 1 (ECCS B or Bypass if Isol all year 2-2 HIGH A in 2014 M
all ECCS isolation) fails CSS-C-06B Sump suction Assumed ECCS B 2r 1 (ECCS A or Bypass if Isol B in 2007 2007 Demand M
all ECCS isolation) fails 2P-35A Assumed Trip pump &
ECCS A or 1 (ECCS B or between 2-2 MEDIUM CSS-C-07A discharge to 2014 Demand M
2CV-5630 all ECCS isolation)
Unaffected test 2E35A 2P35B Assumed Trip pump &
ECCS B or 1 (ECCS A or between CSS-C-07B discharge to 2007 Demand Unaffected t2-2 MEDIUM 2E35B M
2CV-5631 all ECCS isolation) test 2P-3A mii Asume Trp pup &between CSS-C-08A 2P-35A mini 2014 Demand Assumed Trip pump &
CSS A 1 (CSS B.
Unaffected between 2-2 MEDIUM flow M
2CV-5630 test CSS-C-08B 2P35B mini Assumed Trip pump &
CSS B 1 (CSS Al)
Unaffected between 22 MDU flow 2007 Demand M
2CV-5631 test 22 MDU


Enclosure to CNRO-2007-00028 Page 3 of 40 Spatialpt                                             System     AalbeExposure
Enclosure to CNRO-2007-00028 Page 3 of 40 Spatialpt System AalbeExposure Table Used
    ..ID     Description         Laon     Configuration Initiator   liolation .I.mpacts         Backup     Containment   Time   i Table Used (Nblet1) Rank Trainsý CSS-C-09A   Downstream of                                 Assumed   Trip pump &     ECCS A or 1 (ECCS B or               between         2-2   MEDIUM 2E35A in 2014           2014       Demand           M     2CV-5630       all ECCS     isolation)   Unaffected     test CSS-C-09B   Downstream of           2007       Demand     Assumed   Trip pump &     ECCS B or 1 (ECCS A or   Unaffected between         2-2   MEDIUM 2E35B in 2007                                       M     2CV-5631       all ECCS     isolation)                 test CSS-C-1 OA   2P-35A test           2011       Demand     Assumed   Trip pump &     ECCS A f   1 (ECCS B or   Unaffected between         2-2   MEDIUM return in 2011                                     M     2CV-5630       all ECCS     isolation)                 test CSS-C-10B     2P35B test           2011       Demand     Assumed   Trip pump &     ECCS B or 1 (ECCS A or               between return in 2011                                     M     2CV-5631       all ECCS     isolation)   Unaffected     test       2-2   MEDIUM CSS-C-11A   Downstream of           2055       Demand     Assumed   Trip pump &   - ECCS A or 1 iECCS B or   Unaffected between         2-2   MEDIUM 2E35A in 2055                                       M     2CV-5630       all ECCS     isolation)                 test CSSýC-11B   Downstream   of       2055       Demand     Assumed   Trip pump &     ECCS B or 1 (ECCS A or               between         2-2   MEDIUM 2E35B in 2055                                     M       2CV-5631       all ECCS     isolation)   Unaffected     test Upstream of CSS-C-12A   2CV-5612 in           2084       Demand     Assumed   Trip pump &     ECCS A or 1 (ECCS B or   Unaffected between         2-2   MEDIUM 2084                                         M       2CV-5630       all ECCS     isolation)                 test CSS-C-12     Upstream U
..ID Description Laon Configuration Initiator liolation  
2CV-5613   of in         2084       Demand     Assumed   Trip pump &     ECCS B or 1 (ECCS A or   Unaffected between         2-2   MEDIUM 2         2084                               M       2CV-5631       all ECCS     isolation)                 test Downstrea of CSS-C-13A   2CV-5612 in           2084       Demand     Assumed   Trip pump &     CSS A or   1 (CSS B or     2BS-5A   all year       2-2   MEDIUM 2         2084                               M       2CV-5612       all ECCS     isolation)     inside CSS-C-13B   Downstream 2CV-5613 inof          2084       Demand     Assumed   Trip pump &     CSS B or   1 (CSS A or     2BS-5B   all year       2-2   MEDIUM 2         2084                               M       2CV-5613       all ECCS     isolation)     inside Downstream of                                                                                         2CV-5612 CSS-C-14A   2CV-5612 in         Containment Demand       Assumed   Trip pump &         none         2       and closed all year       2-2     LOW.
.I.mpacts Backup Containment Time i
Containment                                       M       2CV-5612                                   system outside Downstream of                                                                                         2CV-5613 CSS-C-14B   2CV-5613 in         Containment Demand       Assumed   Trip pump &         none           2       and closed all year       2-2     LOW Containment                                       M       2CV-5613                                   system outside CSS-C-15A   NaOH to Train           2014     Demand       Assumed   Trip pump &     ECCS A     1 ECCS B     Unaffected between         2-2   MEDIUM A               2         D               M       2CV-5630       E       A   1                           test
(Nblet1)
Rank Trainsý CSS-C-09A Downstream of Assumed Trip pump &
ECCS A or 1 (ECCS B or between 2-2 MEDIUM 2E35A in 2014 2014 Demand M
2CV-5630 all ECCS isolation)
Unaffected test CSS-C-09B Downstream of 2007 Demand Assumed Trip pump &
ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM 2E35B in 2007 M
2CV-5631 all ECCS isolation) test CSS-C-1 OA 2P-35A test 2011 Demand Assumed Trip pump &
ECCS A f 1 (ECCS B or Unaffected between 2-2 MEDIUM return in 2011 M
2CV-5630 all ECCS isolation) test CSS-C-10B 2P35B test 2011 Demand Assumed Trip pump &
ECCS B or 1 (ECCS A or between return in 2011 M
2CV-5631 all ECCS isolation)
Unaffected test 2-2 MEDIUM CSS-C-11A Downstream of 2055 Demand Assumed Trip pump &  
- ECCS A or 1 iECCS B or Unaffected between 2-2 MEDIUM 2E35A in 2055 M
2CV-5630 all ECCS isolation) test CSSýC-11B Downstream of 2055 Demand Assumed Trip pump &
ECCS B or 1 (ECCS A or between 2-2 MEDIUM 2E35B in 2055 M
2CV-5631 all ECCS isolation)
Unaffected test Upstream of CSS-C-12A 2CV-5612 in 2084 Demand Assumed Trip pump &
ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM 2084 M
2CV-5630 all ECCS isolation) test Upstream of CSS-C-12 U
2CV-5613 in 2084 Demand Assumed Trip pump &
ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM 2
2084 M
2CV-5631 all ECCS isolation) test Downstrea of CSS-C-13A 2CV-5612 in 2084 Demand Assumed Trip pump &
CSS A or 1 (CSS B or 2BS-5A all year 2-2 MEDIUM 2
2084 M
2CV-5612 all ECCS isolation) inside Downstream of CSS-C-13B 2CV-5613 in 2084 Demand Assumed Trip pump &
CSS B or 1 (CSS A or 2BS-5B all year 2-2 MEDIUM 2
2084 M
2CV-5613 all ECCS isolation) inside Downstream of 2CV-5612 CSS-C-14A 2CV-5612 in Containment Demand Assumed Trip pump &
none 2
and closed all year 2-2 LOW.
Containment M
2CV-5612 system outside Downstream of 2CV-5613 CSS-C-14B 2CV-5613 in Containment Demand Assumed Trip pump &
none 2
and closed all year 2-2 LOW Containment M
2CV-5613 system outside CSS-C-15A NaOH to Train 2014 Demand Assumed Trip pump &
ECCS A 1 ECCS B Unaffected between 2-2 MEDIUM A
2 D
M 2CV-5630 E
A 1
test


Enclosure to CNRO-2007-00028 Page 4 of 40 Note 1: Tables contained in Yankee Nuclear services Division Calculation No. NSD-018, Rev. 0, August 1997, Consequence Evaluation of ANO-2 EFW, Containment Spray, and Main Steam and FeedwaterSystem Piping, Arkansas Nuclear 1, Unit 2 Note 2: Segments 18A and 18B were not part of the original RI-ISI application (i.e., not within ASME Section Xl scope). Postulated failures of these segments have the same impact as segments 14A and 14B.
Enclosure to CNRO-2007-00028 Page 4 of 40 Note 1: Tables contained in Yankee Nuclear services Division Calculation No. NSD-018, Rev. 0, August 1997, Consequence Evaluation of ANO-2 EFW, Containment Spray, and Main Steam and Feedwater System Piping, Arkansas Nuclear 1, Unit 2 Note 2: Segments 18A and 18B were not part of the original RI-ISI application (i.e., not within ASME Section Xl scope). Postulated failures of these segments have the same impact as segments 14A and 14B.


Enclosure to CNRO-2007-00028 Page 5 of 40 R e fu elin g                         " - -------------               C-S-C----                                                                                  -------------
Enclosure to CNRO-2007-00028 Page 5 of 40 R e fu e lin g  
Water                                 CS.......                     CSS-C-04A Outside0-.Ro            2040 CSSC-1
" - ------------- C-S-C----
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Water CS.......
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chrig           2CV 5647             I"                     CSS-C-06A Outside           2BS-2Pump                                                                                       R-oom2014
.2P60A (LPS,
                                              *                *'                                                          ----------
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CSS-C-06A Outside 2B S-2Pump R-oom2014 CS- -C5420
Room 2040                                                                               Containment--.-----65,-"
,~2C 5648-250-Room 2040 Containment--.-----65,-"
S.tinludes                                              CSS-C-04B Suction to Root .2040                     .        ..                                                              I               2P89B (LPS1)     &
CSS-C-04B S.tinludes Suction to 2P60B (LPSI) &
CSS-C-03B                 c*      6CSS'C-05                                                         -06A Room 2               Rm2                     Room 2007
Root.2040 I
                                                                          .... * ... -2   ....    ...    . ...    ...        *    ....    ...    ....      . .. "          P 35B FIGURE 1 Containment Spray System (CSS) Suction
2P89B (LPS1) 2CV-5649-c CSS-C-03B 6CSS'C-05  
-06A Room 2 Rm2 Room 2007
* -2 P 3 5 B FIGURE 1 Containment Spray System (CSS) Suction


Enclosure to CNRO-2007-00028 Page 6 of 40 S.        . .. ......
Enclosure to CNRO-2007-00028 Page 6 of 40 S.
CSS-C-15A                           css-c-10A 2BS-12A       Room 2007                             Roo i201                            2I-5A RWT
CSS-C-15A css-c-10A CSS-CC-IOB 2BS-12A Room 2007 Roo 201 i
              ~~~2B S-44A           *,   *                          "
2I-5A RWT
                                          .o                                                               Roo
~~~2B S-44A *,  
              ' css-c-O7                 FO                             F Rom 2014 B*S AL R                                                    M                                 I CSS-CC-IOB Room 2014 CSS-C-08A
.o R oo css-c-O7 FO F
                          *2Room2014
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                    *  "        *
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* mini flow 2BS-17A           '      CV-56973-1 CSS-C-15B
*2Room2014 mini flow 2BS-17A CV-56973-1 CSS-C-15B
                          " Room 2007       .                                          ,        i" 2BS-12 B                                             omO7I-5                                B RW 2S*...... T
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                                                      ...... . ..                                        LPCI he
2 B S
                      ,,2BS-44Bi       .          l   .....            *om20*
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                                            -* i                                                         *css-,
o m O 7I-5 B R W T LPCI he
S CSS-C-07B                                       F                                         Roon Room 2007*,hlIF 2BS4                                       CSS-C-09B                     {
,,2BS-44Bi l  
*om20*
i  
*css-,
S CSS-C-07B F
Roon Room 2007*,hlIF 2BS4 CSS-C-09B
{
2P3 ;B lRoom 2007
2P3 ;B lRoom 2007
                              /t **                 *}mini flow 2BS-17B               2CV-5672                                                                                                     FIGURE,2 Containment Spray System (CSS) Discharge
/t **  
*}mini flow 2BS-17B 2CV-5672 FIGURE,2 Containment Spray System (CSS) Discharge


Enclosure to CNRO-2007-00028 Page 7 of 40 III. ADDITIONAL CONSIDERATIONS Piping segments that were determined to be a "Medium", "Low", or "None" consequence category per the consequence evaluation are determined to be high safety significant (HSS) or low safety significant (LSS) by considering the information in Conditions (1) through (10),
Enclosure to CNRO-2007-00028 Page 7 of 40 III.
ADDITIONAL CONSIDERATIONS Piping segments that were determined to be a "Medium", "Low", or "None" consequence category per the consequence evaluation are determined to be high safety significant (HSS) or low safety significant (LSS) by considering the information in Conditions (1) through (10),
below.
below.
Note: Although a large pressure-boundary leak is not always assumed, it was during the RI-ISI evaluations. Also, credit may be taken for plant features and operator actions to the extent these would not be affected by failure of the segment under consideration. If plant features and operator actions are credited, they shall be consistent with those credited in the previous consequence evaluations.
Note: Although a large pressure-boundary leak is not always assumed, it was during the RI-ISI evaluations. Also, credit may be taken for plant features and operator actions to the extent these would not be affected by failure of the segment under consideration. If plant features and operator actions are credited, they shall be consistent with those credited in the previous consequence evaluations.
(1)   Failure of the pressure-retaining function of the segment will not directly or indirectly (e.g., through spatial effects) fail a basic safety function.
(1)
Failure of the pressure-retaining function of the segment will not directly or indirectly (e.g., through spatial effects) fail a basic safety function.


===Response===
===Response===
Per Table I above, any segment classified as "Medium"or "Low"will have at least one train unaffected by the postulatedbreak. Perthe glossary,loss of a single train would typically not constitute loss of a basic function.
Per Table I above, any segment classified as "Medium" or "Low"will have at least one train unaffected by the postulated break. Per the glossary, loss of a single train would typically not constitute loss of a basic function.
(2)   Failure of the pressure-retaining function of the segment will not prevent the plant from reaching or maintaining safe shutdown conditions; and the pressure-retaining function is not significant to safety during mode changes or shutdown. Assume that the plant would be unable to reach or maintain safe shutdown conditions if a pressure boundary failure results in the need for actions outside of plant procedures or available backup plant mitigative features.
(2)
Failure of the pressure-retaining function of the segment will not prevent the plant from reaching or maintaining safe shutdown conditions; and the pressure-retaining function is not significant to safety during mode changes or shutdown. Assume that the plant would be unable to reach or maintain safe shutdown conditions if a pressure boundary failure results in the need for actions outside of plant procedures or available backup plant mitigative features.


===Response===
===Response===
Although the CSS can be used to support shutdown [e.g., as an altemative to Low PressureSafety Injection (LPSI)pumps, the Reactor Water Tank (RWT) provides inventory for filling the refueling canal], the CSS is typically not used to support mode changes or shutdown cooling. Perthe consequence evaluations conducted above, any segment classified as "Medium"or "Low"will have at least one train unaffected by the postulatedbreak. In addition, the consequence evaluation methodology includes an assessment of piping failure during shutdown evolutions.
Although the CSS can be used to support shutdown [e.g., as an altemative to Low Pressure Safety Injection (LPSI) pumps, the Reactor Water Tank (RWT) provides inventory for filling the refueling canal], the CSS is typically not used to support mode changes or shutdown cooling. Per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. In addition, the consequence evaluation methodology includes an assessment of piping failure during shutdown evolutions.
(3)   The pressure-retaining function of the segment is not called out or relied upon in the plant Emergency/Abnormal Operating Procedures (EOPs) or similar guidance as the sole means for successfully performing Operator actions required to mitigate an accident or transient.
(3)
The pressure-retaining function of the segment is not called out or relied upon in the plant Emergency/Abnormal Operating Procedures (EOPs) or similar guidance as the sole means for successfully performing Operator actions required to mitigate an accident or transient.


===Response===
===Response===
While CSS is creditedin the EOPs,per the consequence evaluationsconducted above, any segment classified as "Medium"or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium"or
While CSS is credited in the EOPs, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium" or


Enclosure to CNRO-2007-00028 Page 8.of 40 "Low") are not the sole means for successfully performing operatoractions requiredto mitigate an accident or transient.
Enclosure to CNRO-2007-00028 Page 8.of 40 "Low") are not the sole means for successfully performing operator actions required to mitigate an accident or transient.
(4) The pressure-retaining function of the segment is not called out or relied upon in the plant EOPs or similar guidance as the sole means for assuring long-term containment integrity, monitoring of post-accident conditions, or offsite emergency planning activities.
(4)
The pressure-retaining function of the segment is not called out or relied upon in the plant EOPs or similar guidance as the sole means for assuring long-term containment integrity, monitoring of post-accident conditions, or offsite emergency planning activities.


===Response===
===Response===
While CSS is credited in the EOPs,per the consequence evaluations conducted above, any segment classifiedas "Medium"or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium"or "Low")are not the sole means for assuringlong-term containment integrity. Additionally, the containment coolers provide an altemate means of containmentcooling and the CSS does not provide a post-accident monitoring function or offsite emergency planning function.
While CSS is credited in the EOPs, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium" or "Low") are not the sole means for assuring long-term containment integrity. Additionally, the containment coolers provide an altemate means of containment cooling and the CSS does not provide a post-accident monitoring function or offsite emergency planning function.
(5) Failure of the pressure-retaining function of the segment will not result in an unintentional release of radioactive material that would result in implementing offsite radiological protective actions.
(5)
Failure of the pressure-retaining function of the segment will not result in an unintentional release of radioactive material that would result in implementing offsite radiological protective actions.


===Response===
===Response===
Failureof the CSS will not cause such events. Rather, the function of the CSS is to respond to such events (e.g., LOCAs). Additionally, per the consequence evaluations conducted above, any segment classified as "Medium"or "Low" will have at least one train unaffected by the postulated break. As such; the design basis function of the CSS will still be fulfilled.
Failure of the CSS will not cause such events. Rather, the function of the CSS is to respond to such events (e.g., LOCAs). Additionally, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such; the design basis function of the CSS will still be fulfilled.
The RISC process shall demonstrate that the defense-in-depth philosophy is maintained.
The RISC process shall demonstrate that the defense-in-depth philosophy is maintained.
Defense-in-depth is maintained if:
Defense-in-depth is maintained if:
(6) Reasonable balance is preserved among prevention of core damage, prevention of containment failure or bypass, and mitigation of an offsite release.
(6)
Reasonable balance is preserved among prevention of core damage, prevention of containment failure or bypass, and mitigation of an offsite release.


===Response===
===Response===
This balance is preserved as there'is no change to the design, design basis, or operation of the CSS by this change. The CSS is still required to reliably perform its safety-relatedfunction.
This balance is preserved as there' is no change to the design, design basis, or operation of the CSS by this change. The CSS is still required to reliably perform its safety-related function.
(7) There is no over-reliance on programmatic activities and operator actions to compensate for weaknesses in the plant design.
(7)
There is no over-reliance on programmatic activities and operator actions to compensate for weaknesses in the plant design.


===Response===
===Response===
The consequence evaluation conducted reflects the as-operated/as-designedplant.
The consequence evaluation conducted reflects the as-operated/as-designed plant.
This evaluation does not increasethe reliance on programmaticactivities or operator actions. Operatoractions, when credited, are credited consistent with the approved RI-ISI consequence evaluation methodology.
This evaluation does not increase the reliance on programmatic activities or operator actions. Operator actions, when credited, are credited consistent with the approved RI-ISI consequence evaluation methodology.


Enclosure to CNRO-2007-00028 Page 9 of 40 (8)   System redundancy, independence, and diversity are preserved commensurate with the expected frequency of challenges, consequences of failure of the system, and associated uncertainties in determining these parameters.
Enclosure to CNRO-2007-00028 Page 9 of 40 (8)
System redundancy, independence, and diversity are preserved commensurate with the expected frequency of challenges, consequences of failure of the system, and associated uncertainties in determining these parameters.


===Response===
===Response===
System redundancy,independence, and diversity are preserved since there is no change to the design, design basis, or operation of the CSS by this change. The CSS will still be required to reliablyperform its safety-relatedfunction.
System redundancy, independence, and diversity are preserved since there is no change to the design, design basis, or operation of the CSS by this change. The CSS will still be required to reliably perform its safety-related function.
(9)   Potential for common cause failures is taken into account in the risk analysis categorization.
(9)
Potential for common cause failures is taken into account in the risk analysis categorization.


===Response===
===Response===
Yes, "common cause"is a fundamental aspect of the consequence evaluation methodology and, therefore, is taken into account (e.g., see Table 1-2 of ANO2-R&R-004, Rev. 1).
Yes, "common cause" is a fundamental aspect of the consequence evaluation methodology and, therefore, is taken into account (e.g., see Table 1-2 of ANO2-R&R-004, Rev. 1).
(10) Independence of fission-product barriers is not degraded.
(10) Independence of fission-product barriers is not degraded.


===Response===
===Response===
Independence of fission barrieris not degraded since no new dependencies have been created. The CSS is still required to reliablyperform its safety-related function.
Independence of fission barrier is not degraded since no new dependencies have been created. The CSS is still required to reliably perform its safety-related function.
If any of the above ten (10) conditions are not true, then HSS shall be assigned. Otherwise, LSS is assigned.
If any of the above ten (10) conditions are not true, then HSS shall be assigned. Otherwise, LSS is assigned.
Based upon the above, segments assigned to "Medium" or "Low" consequence rank do not have to be moved into the high consequence rank and can be assigned as "LSS" provided "safety margin" is adequately addressed below.
Based upon the above, segments assigned to "Medium" or "Low" consequence rank do not have to be moved into the high consequence rank and can be assigned as "LSS" provided "safety margin" is adequately addressed below.
Line 176: Line 267:


===Response===
===Response===
Since the safety analysis acceptance criteriain the plant licensing basis are not changed, safety margins remain unchanged and, therefore, acceptable.
Since the safety analysis acceptance criteria in the plant licensing basis are not changed, safety margins remain unchanged and, therefore, acceptable.


Enclosure to CNRO-2007-00028 Page 10 of 40 Based upon all the preceding factors a final RISC for the CSS has been determined. These results are provided in Table 2.
Enclosure to CNRO-2007-00028 Page 10 of 40 Based upon all the preceding factors a final RISC for the CSS has been determined. These results are provided in Table 2.
TABLE 2 Final RISC Assiqnments ID                             Description               Spatial Location Rank CSS-C-01       Common RWT suction outside                       Outside       HIGH CSS-C-02       Common RWT suction inside                           2040       HIGH CSS-C-03A       RWT suction A in 2040                               2040       LOW CSS-C-03B       RWT suction B in 2040                               2040       HIGH CSS-C-04A       RWT suction A in 2014                               2014*       LOW CSS-C-04B       RWT suction B in 2007                               2007       LOW CSS-C-05       RWT suction B in 2006                               2006       LOW CSS-C-06A       Sump suction A in 2014                             2014       HIGH CSS-C-06B       Sump suction B in 2007                             2007       HIGH CSS-C-07A       2P-35A discharge to 2E35A                           2014       LOW CSS-C-07B       2P35B discharge to 2E35B                           2007       LOW CSS-C-08A       2P-35A mini flow                                   2014       LOW CSS-C-08B       2P35B mini flow                                     2007       LOW CSS-C-09A       Downstream of 2E35A in 2014                         2014       LOW CSS-C-09B       Downstream of 2E35B in 2007                         2007       LOW CSS-C-10A       2P-35A test return in 2011                         2011       LOW CSS-C-10B       2P35B test return in>2011                           2011       LOW CSS-C-11A       Downstream of 2E35A in 2055.                       2055         LOW CSS-C-1 1B      Downstream of 2E35B in 2055                         2055       LOW CSS-C-12A       Upstream of 2CV-5612 in 2084                       2084         LOW CSS-C-12B       Upstream of 2CV-5613 in 2084                       2084         LOW CSS-C-13A       Downstream of 2CV-5612 in 2084                     2084         LOW CSS-C-13B       Downstream of 2CV-5613 in 2084                     2084         LOW CSS-C-14A       Downstream of 2CV-5612 in Containment           Containment     LOW CSS-C-14B       Downstream of 2CV-5613 in Containment           Containment     LOW CSS-C-15A       NaOH to Train A                                   2014         LOW CSS-C-1 5B       NaOH to Train B                                   2007         LOW CSS-C-1 6       RWT to SFPP & charging                         Outside 2040     LOW CSS-C-17A       Service air connection to Train A                 2084         LOW
TABLE 2 Final RISC Assiqnments ID Description Spatial Location Rank CSS-C-01 Common RWT suction outside Outside HIGH CSS-C-02 Common RWT suction inside 2040 HIGH CSS-C-03A RWT suction A in 2040 2040 LOW CSS-C-03B RWT suction B in 2040 2040 HIGH CSS-C-04A RWT suction A in 2014 2014*
LOW CSS-C-04B RWT suction B in 2007 2007 LOW CSS-C-05 RWT suction B in 2006 2006 LOW CSS-C-06A Sump suction A in 2014 2014 HIGH CSS-C-06B Sump suction B in 2007 2007 HIGH CSS-C-07A 2P-35A discharge to 2E35A 2014 LOW CSS-C-07B 2P35B discharge to 2E35B 2007 LOW CSS-C-08A 2P-35A mini flow 2014 LOW CSS-C-08B 2P35B mini flow 2007 LOW CSS-C-09A Downstream of 2E35A in 2014 2014 LOW CSS-C-09B Downstream of 2E35B in 2007 2007 LOW CSS-C-10A 2P-35A test return in 2011 2011 LOW CSS-C-10B 2P35B test return in> 2011 2011 LOW CSS-C-11A Downstream of 2E35A in 2055.
2055 LOW CSS-C-1 1 B Downstream of 2E35B in 2055 2055 LOW CSS-C-12A Upstream of 2CV-5612 in 2084 2084 LOW CSS-C-12B Upstream of 2CV-5613 in 2084 2084 LOW CSS-C-13A Downstream of 2CV-5612 in 2084 2084 LOW CSS-C-13B Downstream of 2CV-5613 in 2084 2084 LOW CSS-C-14A Downstream of 2CV-5612 in Containment Containment LOW CSS-C-14B Downstream of 2CV-5613 in Containment Containment LOW CSS-C-15A NaOH to Train A 2014 LOW CSS-C-1 5B NaOH to Train B 2007 LOW CSS-C-1 6 RWT to SFPP & charging Outside 2040 LOW CSS-C-17A Service air connection to Train A 2084 LOW


Enclosure to CNRO-2007-00028 Page 11 of 40 ID                                Description.                             Spatial Location       Rank CSS-C-17B         Service air connection to Train B                                   2084           LOW CSS-C-1 8A         Downstream of 2BS-5A in Containment                             Containment         LOW CSS-C-1 8B         Downstream of 2BS-5B in Containment                             Containment         LOW V.     CONSEQUENCE INFORMATION REPORTS The Consequence Information Reports, which were developed for the ANO-2 RI-ISI program, summarize the consequence evaluation process. 4 As noted earlier, the CSS evaluation did not credit the Containment Cooling System (CCS). As such, the consequence rank identified herein is conservative for a number of segments. However, the rank for high-ranked segments would not change since failure of these segments typically results in a loss of all ECCS and / or a containment bypass potential.
Enclosure to CNRO-2007-00028 Page 11 of 40 I D Description.
FMECA - Consequence Information Report                                   CalculationNo. A-PENG.CALC-015. Rev. 00 14-Sep-9                                                                                         Page A2 of A31 Consequence ID: CSS-C-01 Consequence
Spatial Location Rank CSS-C-17B Service air connection to Train B 2084 LOW CSS-C-1 8A Downstream of 2BS-5A in Containment Containment LOW CSS-C-1 8B Downstream of 2BS-5B in Containment Containment LOW V.
CONSEQUENCE INFORMATION REPORTS The Consequence Information Reports, which were developed for the ANO-2 RI-ISI program, summarize the consequence evaluation process. 4 As noted earlier, the CSS evaluation did not credit the Containment Cooling System (CCS). As such, the consequence rank identified herein is conservative for a number of segments. However, the rank for high-ranked segments would not change since failure of these segments typically results in a loss of all ECCS and / or a containment bypass potential.
FMECA - Consequence Information Report Calculation No. A-PENG.CALC-015. Rev. 00 14-Sep-9 Page A2 of A31 Consequence ID: CSS-C-01 Consequence


== Description:==
== Description:==
Degrdation of common RWT suction outside auxiliary building during an independent demand (line 2HCB-24 outside)
Degrdation of common RWT suction outside auxiliary building during an independent demand (line 2HCB-24 outside)
Break Size:       Large                                       Isolability of Break. No ISO Comments: Unisolable.
Break Size:
Spatial Effects: Local                                       Effected Location:     Outside Spatial Effects Comments: The common RWT suction piping outside the auxiliary building (near the RWT) can not propagate to the auxiliary building and impact safety equipment' Initiating Event:' N                                         Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,
Large Isolability of Break. No ISO Comments: Unisolable.
Spatial Effects: Local Effected Location:
Outside Spatial Effects Comments: The common RWT suction piping outside the auxiliary building (near the RWT) can not propagate to the auxiliary building and impact safety equipment' Initiating Event:' N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,
demand stress of RWT head is not significantly different during demand).
demand stress of RWT head is not significantly different during demand).
Loss of System: SM-3                                         System IPE MD:         CSS, HPSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.
Loss of System: SM-3 System IPE MD:
Loss of Train:   N                                           Train ID:               N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.
CSS, HPSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.
Consequence Category: HIGH                 03               Consequence Rank                     0 4 Entergy   submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.
Loss of Train:
N Train ID:
N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.
Consequence Category: HIGH 03 Consequence Rank 0
4 Entergy submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.


Enclosure to CNRO-2007-00028 Page 12 of 40 FMECA - Consequence Information Report                                     Calculat-,n No. A-PENG-CALC-O15. Rev. 00 14-Sep-9                                                                                           Page A3 of A31 Consequence ID: CSS-C-02 Consequence
Enclosure to CNRO-2007-00028 Page 12 of 40 FMECA - Consequence Information Report Calculat-,n No. A-PENG-CALC-O15. Rev. 00 14-Sep-9 Page A3 of A31 Consequence ID: CSS-C-02 Consequence


== Description:==
== Description:==
Degradation of common RWT suction upstream of 2CV-5630 & 5631 in auxiliary building during an independent demand (line 2HCB-24 in auxiliary building)
Degradation of common RWT suction upstream of 2CV-5630 & 5631 in auxiliary building during an independent demand (line 2HCB-24 in auxiliary building)
Break Size:       Large                                         Isolability of Break: No ISO Comments: Unisolable.
Break Size:
Spatial Effects: Propagatio n                                   Effected Location:     Room 2040 Spatial Effects Comments: The common RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 201 1) through floor drains and the east stairway. Also, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014). Detection is provided by auxiliary building sump high level alarm and the ECCS room flood alarms in the control room, but this is irrelevant since the break is unisolable.
Large ISO Comments: Unisolable.
Initiating Event: N                                            Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M)initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
Isolability of Break: No Spatial Effects: Propagatio Spatial Effects Comments:
Initiating Event: N n
Effected Location:
Room 2040 The common RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 201 1) through floor drains and the east stairway. Also, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014). Detection is provided by auxiliary building sump high level alarm and the ECCS room flood alarms in the control room, but this is irrelevant since the break is unisolable.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
demand stress of RWT head is not significantly different during demand).
demand stress of RWT head is not significantly different during demand).
Loss of System: SM-3                                           System IPE ED:         CSS, -PSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.
Loss of System: SM-3 System IPE ED:
Loss of Train:   N                                             Train ID:               N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of RIf 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.
CSS, -PSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.
Consequence Category: FUGH                   13               Consequence Rank                     1:1 Consequence Category: HIGH                   0                 Consequence Rank                     0
Loss of Train:
N Train ID:
N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of RIf 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.
Consequence Category: FUGH 13 Consequence Rank 1:1 Consequence Category: HIGH 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 13 of 40 FMECA - Consequence Information Report                                     CalculatonNo. A-PENG*CALC-0)5. Rev. 00 14-Sep-9                                                                                         Page A4 of A31 Consequence ID: CSS-C-03A Consequence
Enclosure to CNRO-2007-00028 Page 13 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG*CALC-0)5. Rev. 00 14-Sep-9 Page A4 of A31 Consequence ID: CSS-C-03A Consequence


== Description:==
== Description:==
Degradation of RWT suction A downstream of 2CV-5630 in Room 2040 during an independent demand (line 2HCB-26 in Room 2040)
Degradation of RWT suction A downstream of 2CV-5630 in Room 2040 during an independent demand (line 2HCB-26 in Room 2040)
Break Size:     Large                                         Isolabifity of Break: Yes ISO Comments: 2CV-5630-1 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:   Room 2040 Spatial Effects Comments: RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV.
Large Isolabifity of Break: Yes ISO Comments: 2CV-5630-1 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2040 Spatial Effects Comments: RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV.
5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
demand stress of RWT head is not significantly different during demand).
demand stress of RWT head is not significantly different during demand).
Loss of System: SM.3                                           System IPE ID:       CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM.3 System IPE ID:
Loss of Train:   TM-3                                           Train El):           CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train El):
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium, based on I backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium, based on I backup train (isolation). No impact on containment isolation.
Consequence Category: MEDIUM                                   Consequence Rank                   r' Consequence Category: MEDIUM                 El               Consequence Rank                   C
Consequence Category: MEDIUM Consequence Rank r'
Consequence Category: MEDIUM El Consequence Rank C


Enclosure to CNRO-2007-00028 Page 14 of 40 FMECA - Consequence Information Report                                     CalculaftonNo. A-PENG-CALC-0)5. Rev. 00 14-Sep-9                                                                                          Page A5 of A31 Consequence ED: CSS-C-03B Consequence
Enclosure to CNRO-2007-00028 Page 14 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculafton No. A-PENG-CALC-0)5. Rev. 00 Page A5 of A31 Consequence ED: CSS-C-03B Consequence


== Description:==
== Description:==
Degradation of RWT suction B downstream of 2CV-5631 in Room 2040 during an independent demand (line 214CB-27 in Room 2040)
Degradation of RWT suction B downstream of 2CV-5631 in Room 2040 during an independent demand (line 214CB-27 in Room 2040)
Bre"k Size:     Large                                         Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWTIevel alarm will also occur, but it could be associated with the assumed LOCA condition.
Bre"k Size:
Spatial Effects: Propagatio n                                 Effected Location:   Room 2040 Spatial Effects Comments: RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWTIevel alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagatio Spatial Effects Comments:
Initiating Event: N n
Effected Location:
Room 2040 RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                            Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
demand stress of RWT head is not significantly different during demand).
demand stress of RWT head is not significantly different during demand).
Loss of System: SM-3                                           System IPE ID:       CSS, HPSI LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to assumed impact on MCC 2B52 before isolation. Normally closed 2CV-5612-1 can not fully open for train A success due to flood impact on its breaker in MCC2B52.
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-2                                         Train ED:             HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as shown above.
CSS, HPSI LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to assumed impact on MCC 2B52 before isolation. Normally closed 2CV-5612-1 can not fully open for train A success due to flood impact on its breaker in MCC2B52.
Loss of Train:
TM-2 Train ED:
HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as shown above.
Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup train). No impact on containment isolation.
Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup train). No impact on containment isolation.
Consequence Category: FUGH                   El               Consequence Rank                     E]
Consequence Category: FUGH El Consequence Rank E]
Consequence Category: HIGH                   0                 Consequence Rank                     C
Consequence Category: HIGH 0
Consequence Rank C


Enclosure to CNRO-2007-00028 Page 15 of 40 FMECA - Consequence Information Report                                       Calculadon No. A-PENG-CALC-015, Rev. 00 14-Sep-9                                                                                             Page A6 of A3)
Enclosure to CNRO-2007-00028 Page 15 of 40 FMECA - Consequence Information Report Calculadon No. A-PENG-CALC-015, Rev. 00 14-Sep-9 Page A6 of A3)
Consequence ID: CSS-C-04A Consequence
Consequence ID: CSS-C-04A Consequence


== Description:==
== Description:==
  'Degradation of Suction A downstream of 2CV-5630 & 2CV-5649 in Room 2014 during an independent demand (lines 2HCB-26 and 2HCB-15 downstream of 2CV-5649 in Room 2014)
  'Degradation of Suction A downstream of 2CV-5630 & 2CV-5649 in Room 2014 during an independent demand (lines 2HCB-26 and 2HCB-15 downstream of 2CV-5649 in Room 2014)
Break Size:       Large'.                                         Isolability of Breiak Yes ISO Comments: 2CV-5630-1 can be closed from the control room (break is assumed to occur during RWIT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm'if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                     Effected Location:   Room 2014 Spatial Effects Comments: RWT suction piping will likely flood ECCS train A in Room 2014 before isolation.
Large'.
Isolability of Breiak Yes ISO Comments: 2CV-5630-1 can be closed from the control room (break is assumed to occur during RWIT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm'if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2014 Spatial Effects Comments: RWT suction piping will likely flood ECCS train A in Room 2014 before isolation.
Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2007 (ECCS train B).
Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2007 (ECCS train B).
However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA CM) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA CM) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
demand stress of RWT head is not signficantly different during demand).
demand stress of RWT head is not signficantly different during demand).
Loss of System: SM-3.                                           System IPE ID:         CSS, -PSI, LPS1 System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3.
Loss of Train:   TM-3                                           Train iD:             CSS A, HPSI A, LPSI A Train Recovery; Isolation success leads to loss of ECCS train A.
System IPE ID:
CSS, -PSI, LPS1 System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train iD:
CSS A, HPSI A, LPSI A Train Recovery; Isolation success leads to loss of ECCS train A.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Category: lffiDrLJM                 13 ,             Consequence Rank                       13 Consequence Category: MEDIUM                   0               Consequence Rank                       0
Consequence Category: lffiDrLJM 13,
Consequence Rank 13 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 16 of 40 FMECA - Consequence Information Report,                                     CalculationNo. A-PENG-CALC-0Z5, Rev. 00 14-Sep-9                                                                                             Page A7 of A31 Consequence ID: CSS-C-04B Consequence
Enclosure to CNRO-2007-00028 Page 16 of 40 FMECA - Consequence Information Report, Calculation No. A-PENG-CALC-0Z5, Rev. 00 14-Sep-9 Page A7 of A31 Consequence ID: CSS-C-04B Consequence


== Description:==
== Description:==
Degradation of Suction B downstream of 2CV-5631 & 2CV-5650 in Room 2007 during an independent demand (lines 2HCB-27 and 2HCB-13 downstream of 2CV-5650 in Room 2007)
Degradation of Suction B downstream of 2CV-5631 & 2CV-5650 in Room 2007 during an independent demand (lines 2HCB-27 and 2HCB-13 downstream of 2CV-5650 in Room 2007)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed fi-om the control room (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2007 Spatial Effects Comments: RWT suction piping will likely flood ECCS train B in Room 2007 before isolation.
Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed fi-om the control room (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2007 Spatial Effects Comments: RWT suction piping will likely flood ECCS train B in Room 2007 before isolation.
Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2014 (ECCS train A).
Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2014 (ECCS train A).
However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,
demand stress of RWT head is not signficantly different during demand).
demand stress of RWT head is not signficantly different during demand).
Loss of System: SM-3.                                           System WPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3.
Loss of Train:   TM-3                                           Train ID:             CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
System WPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). No impact on containment isolation.
Consequence Category: MEDIUM                   11               Consequence Rank                       []
Consequence Category: MEDIUM 11 Consequence Rank
Consequence Category: MEDIUM                   0               Consequence Rank                       0
[]
Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 17 of 40 FMECA - Consequence Information Report                                       Calklatiwi No. A-PENG-C4LC-O)5. Rev. O0 14-Sep-9                                                                                             Page A8 of A31 Consequence ID: CSS-C-05 Consequence
Enclosure to CNRO-2007-00028 Page 17 of 40 FMECA - Consequence Information Report Calklatiwi No. A-PENG-C4LC-O)5. Rev. O0 14-Sep-9 Page A8 of A31 Consequence ID: CSS-C-05 Consequence


== Description:==
== Description:==
Degradation of RWT suction B downstream of 2CV-5631 in Room 2006 during an independent demand (line 2HCB-27 in Room 2006)
Degradation of RWT suction B downstream of 2CV-5631 in Room 2006 during an independent demand (line 2HCB-27 in Room 2006)
Break Size:       Large                                           Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                       Effected Location:   Room 2006 Spatial Effects Comments: Failure to isolate is assumed to propagate into ECCS Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on an SI signal.
Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2006 Spatial Effects Comments: Failure to isolate is assumed to propagate into ECCS Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on an SI signal.
Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level'alarm in the control room.
Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level'alarm in the control room.
Initiating Event: N                                               Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi)         initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,
demand stress of RWT head is not significantly different during demand).
demand stress of RWT head is not significantly different during demand).
Loss of System: SM-3                                             System IPE ID:         CSS, HPS!, LPSI System.Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion, flooding, or insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3                                             Train ED:             CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
CSS, HPS!, LPSI System.Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion, flooding, or insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ED:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Category: MEDIUM                                     Consequence Rank                     0.
Consequence Category: MEDIUM Consequence Rank 0.
Consequence Category: MEDIUM                   D                 Consequence Rank                     0
Consequence Category: MEDIUM D
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 18 of 40 FMECA - Consequence Information Report                                     Calculaton No:A-PENG-CALC-01. Rev. 00 I4-Sep-9                                                                                           Page 'A9 of A31 Consequence ID: CSS-C-06A Consequence
Enclosure to CNRO-2007-00028 Page 18 of 40 FMECA - Consequence Information Report Calculaton No:A-PENG-CALC-01. Rev. 00 I4-Sep-9 Page 'A9 of A31 Consequence ID: CSS-C-06A Consequence


== Description:==
== Description:==
Degradation of containment sump suction A upstream of 2CV-5649 during an independent demand (line 2HCB-15 from containment sump to 2CV-5649)
Degradation of containment sump suction A upstream of 2CV-5649 during an independent demand (line 2HCB-15 from containment sump to 2CV-5649)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: 2CV-5647-1 can be closed from the control room. Detection is based on Room 2014 flood alarm and auxiliary building sump level.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2014 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train A in Room 2014 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.
Large Isolability of Break: Yes ISO Comments: 2CV-5647-1 can be closed from the control room. Detection is based on Room 2014 flood alarm and auxiliary building sump level.
Spatial Effects: Propagation Effected Location:
Room 2014 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train A in Room 2014 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.
Detection is provided by Room 2014 flood and auxiliary building sump high level alarms in the control room.
Detection is provided by Room 2014 flood and auxiliary building sump high level alarms in the control room.
Initiating Event: N                                           Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                           System IPE ID:         CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3                                         Train ID:             CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A recirculation.
CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and .1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5647-1 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18)
Loss of Train:
Consequence Category:   HIGH               0   .            Consequence Rank                     0
TM-3 Train ID:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A recirculation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and.1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5647-1 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18)
Consequence Category: HIGH 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 19 of 40 FMECA - Consequence Information Report                                     Calculation No. A-PENG-CALC-O)5, Rev. 00 14-Sep-9                                                                                          Page AIO of AS)
Enclosure to CNRO-2007-00028 Page 19 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CALC-O)5, Rev. 00 Page AIO of AS)
Consequence EID: CSS-C-06B Consequence
Consequence EID: CSS-C-06B Consequence


== Description:==
== Description:==
Degradation of containment sump suction B upstream of 2CV-5650 during an independent demand (line 2HCB-13 from containment sump to 2CV-5650)
Degradation of containment sump suction B upstream of 2CV-5650 during an independent demand (line 2HCB-13 from containment sump to 2CV-5650)
Break Size:     Large                                         I olability of Break: Yes ISO Comments: 2CV-5648-2 can be closed from the control room. Detection is based on Room 2007 flood alarm and auxiliary building sump level.
Break Size:
Spatial Effects: Propagation.                                   Effected Location:     Room 2007 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train B in Room 2007 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.
Large I olability of Break: Yes ISO Comments: 2CV-5648-2 can be closed from the control room. Detection is based on Room 2007 flood alarm and auxiliary building sump level.
Spatial Effects: Propagation.
Effected Location:
Room 2007 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train B in Room 2007 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.
Detection is provided by Room 2007 flood and auxiliary.building sump high level alarms in the control room.
Detection is provided by Room 2007 flood and auxiliary.building sump high level alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                             System IPE ID:         CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3 '                                         Train ID:             CSS B, -PSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B recirculation.
CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Loss of Train:
TM-3 '
Train ID:
CSS B, -PSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B recirculation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5648-2 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5648-2 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18).
Consequence Category; lUGH                   0                 Consequence Rank                     13 Consequence Category: HIGH                   0                 Consequence Rank                     0
Consequence Category; lUGH 0
Consequence Rank 13 Consequence Category: HIGH 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 20 of 40 FMECA - Consequence Information Report                                       CalculatonNo. A-PENG-CALC-0IS, Rev. 00 14-Sep-9                                                                                           Page All of AS)
Enclosure to CNRO-2007-00028 Page 20 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG-CALC-0IS, Rev. 00 14-Sep-9 Page All of AS)
Consequence ID: CSS-C-07A Consequence
Consequence ID: CSS-C-07A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge to heat exchanger 2E35A during an independent demand (line 2GCB-10)
Degradation of Pump 2P35A discharge to heat exchanger 2E35A during an independent demand (line 2GCB-10)
Break Size:       Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWr (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxilhazy building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location: Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventosy to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWr (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxilhazy building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: SM-3                                             System IPE ID:           CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventosy to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Loss of Train:   TM-3                                           Train ED:               CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ED:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation).
Consequence Category: MEDIUM                     F-1             Consequence'Rank                       E3 Consequence Category: MEDIIJM                   0               Consequence Rank                       0
Consequence Category: MEDIUM F-1 Consequence'Rank E3 Consequence Category: MEDIIJM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 21 of 40 FMECA - Consequence Information Report                                     CalculaionvNo.A-PENG-CALC-OJ5,Revp 00 14-Sep-9                                                                                           Page A12 of A31 Consequence ID: CSS-C-07B Consequence
Enclosure to CNRO-2007-00028 Page 21 of 40 FMECA - Consequence Information Report CalculaionvNo.A-PENG-CALC-OJ5, Revp 00 14-Sep-9 Page A12 of A31 Consequence ID: CSS-C-07B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge to heat exchanger 2E35B during an independent demand (line 2GCB-11)
Degradation of Pump 2P35B discharge to heat exchanger 2E35B during an independent demand (line 2GCB-11)
Break Size:     Large                                         Isolahility of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:       Room 2007 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump-recirculatian. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Large Isolahility of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: SM-3                                           System IPE ID:       .. CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in containment sump to support recirculation.
Room 2007 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump-recirculatian. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Loss of Train:   TM-3                                         Train ID:               CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:  
.. CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Category: MEDIUM                                   Consequence Rank                       E3 Consequence Category: MEDIUM                   0               Consequence Rank                       0
Consequence Category: MEDIUM Consequence Rank E3 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 22 of 40 FMECA - Consequence Information Report                                         CalculationNo. A-PENG-CALC-015,S. Rn, 0 14-Sep-9                                                                                            Page A)3 of A31 Consequence ID: CSS-C-08A Consequence
Enclosure to CNRO-2007-00028 Page 22 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CALC-015, S. Rn, 0
Page A)3 of A31 Consequence ID: CSS-C-08A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A mini flow in Room 2014 during an independent demand (line 2GCB-35 and line 2DCB-11 upstream of 2CV-5673 in Room 2014)
Degradation of Pump 2P35A mini flow in Room 2014 during an independent demand (line 2GCB-35 and line 2DCB-11 upstream of 2CV-5673 in Room 2014)
Break Size:       Large                                           Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2A in Room 2014 which would allow operation of HPSI A and LPSI A without further leakage into the room. Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm.
Break Size:
Spatial Effects: Propagatio n                                     Effected Location:     Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 if not isolated. Another oppommity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5647 or 2CV-5649 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2A in Room 2014 which would allow operation of HPSI A and LPSI A without further leakage into the room. Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm.
Initiating Event: N                                                Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagatio Spatial Effects Comments:
Loss of System: SM-3                                               System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Initiating Event: N n
Loss of Train:   TM-3                                             Train ID:             CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of only CSS train A. Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train A due to flooding in the room.
Effected Location:
Room 2014 Flooding is assumed to affect train A ECCS in Room 2014 if not isolated. Another oppommity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5647 or 2CV-5649 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).
Loss of Train:
TM-3 Train ID:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of only CSS train A. Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train A due to flooding in the room.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup trains - CSS B in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS B or 2 isolations).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup trains - CSS B in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS B or 2 isolations).
Consequence Category: MEDFJM                     11,               Consequence Rank                     1-1 Consequence Category: MEDIUM                     0                 Consequence Rank                     0
Consequence Category: MEDFJM 11, Consequence Rank 1-1 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 23 of 40 FMECA - Consequence Information Report                                         CalculationNo.A-PENG.CAL. -015, Rev. 00 Page AU4 of AR) 14-Sep-9 Consequence ID: CSS-C-08B Consequence
Enclosure to CNRO-2007-00028 Page 23 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG.CAL. -015, Rev. 00 Page AU4 of AR)
Consequence ID: CSS-C-08B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B mini flow in Room 2007 during an independent demand (line 2GCB-34 and line 2DCB-13 upstream of 2CV-'5672 in Room 2007)
Degradation of Pump 2P35B mini flow in Room 2007 during an independent demand (line 2GCB-34 and line 2DCB-13 upstream of 2CV-'5672 in Room 2007)
Break Size:     -Large                                           Isolabitity of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is.
Break Size:  
-Large Isolabitity of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is.
assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2B in Room 2007 which would allow operation of HPSI B and LPSI B without further leakage into the room. Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm.
assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2B in Room 2007 which would allow operation of HPSI B and LPSI B without further leakage into the room. Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm.
Spatial Effects: Propagatia n                                     Effected Location:     Room 2007 Spatial Effects Comments: Flooding is assumed to affect train B ECCS in Room 2007 if not isolated. Another opportunity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5648 or 2CV-5650 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Spatial Effects: Propagatia Spatial Effects Comments:
Initiating Event: N                                              Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N n
Loss of System: SM-3                                             System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to leadto loss of containment sump (common cause failure of ECCS recirculation).
Effected Location:
Loss of Train:   TM-3                                           Train ED:               CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of only CSS train B.-Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train B due to flooding in the room.
Room 2007 Flooding is assumed to affect train B ECCS in Room 2007 if not isolated. Another opportunity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5648 or 2CV-5650 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to leadto loss of containment sump (common cause failure of ECCS recirculation).
Loss of Train:
TM-3 Train ED:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of only CSS train B.-Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train B due to flooding in the room.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18.(uncxpected frequency of challenge, between test exposure, and I backup trains - CSS A in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS A or 2 isolations).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18.(uncxpected frequency of challenge, between test exposure, and I backup trains - CSS A in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS A or 2 isolations).
Consequence Category: MEDIUM                   El               Consequence Rank                     IJ Consequence Category: MEDIUM                   0               Consequence Rank                     0
Consequence Category: MEDIUM El Consequence Rank IJ Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 24 of 40 FMECA - Consequence Information Report                                     CalculatonNo. A-PENG-CALC-O5. Rev. 00
Enclosure to CNRO-2007-00028 Page 24 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG-CALC-O5. Rev. 00
  ,4-Sep-9                                                                                           Page A15 of A3 Consequence ID: CSS-C-09A Consequence
,4-Sep-9 Page A15 of A3 Consequence ID: CSS-C-09A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2014 during an independent demand (line 2GCB-16 in Room 2014)
Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2014 during an independent demand (line 2GCB-16 in Room 2014)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:       Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur, Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                           Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi)initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: SM-3                                           System IPE ED:           CSS, HPSI. LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur, Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Loss of Train:   TM-3                                         Train ID:               CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ED:
CSS, HPSI. LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and lbackup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and lbackup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Category: ME*DIUrM                 13             Consequence Rank                       []
Consequence Category: ME*DIUrM 13 Consequence Rank
Consequence Category: MEDIUM                   0               Consequence Rank                       0
[]
Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 25 of 40 FMECA - Consequence Information Report                                     Calculafion No. A-PENG-CALC-OiS. Rev. 00 14-Sep.9                                                                                           Page A16 of A31 Consequence ID: CSS-C-09B Consequence
Enclosure to CNRO-2007-00028 Page 25 of 40 FMECA - Consequence Information Report Calculafion No. A-PENG-CALC-OiS. Rev. 00 14-Sep.9 Page A16 of A31 Consequence ID: CSS-C-09B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2007 during an independent demand (line 2GCB-17 in Room 2007)
Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2007 during an independent demand (line 2GCB-17 in Room 2007)
Break Size:       Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase): Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:       Room 2007 Spatial Effects Comments: Flooding is assumed to affect train B ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase): Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: SM-3                                           System IPE ID:           CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Room 2007 Spatial Effects Comments: Flooding is assumed to affect train B ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.
Loss of Train:   TM-3                                           Train ID:               CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9. 18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation),
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9. 18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation),
Consequence Category': hEEDUJM                 0               Consequence Rank                     r13 Consequence Category: MEDIUM                   0               Consequence Rank                     C
Consequence Category': hEEDUJM 0
Consequence Rank r13 Consequence Category: MEDIUM 0
Consequence Rank C


Enclosure to CNRO-2007-00028 Page 26 of 40 FMECA - Consequence Information Report                                     Cak,,dadon No.A-PENG-C4LC-O i. Rm. 00 14-Sep-9                                                                                           Page A]7 of A31 Consequence ID: CSS-C-10A Consequence
Enclosure to CNRO-2007-00028 Page 26 of 40 FMECA - Consequence Information Report Cak,,dadon No. A-PENG-C4LC-O i. Rm. 00 14-Sep-9 Page A]7 of A31 Consequence ID: CSS-C-10A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge test return upstream of 2SI-5A in Room 2011 during an independent demand (line 2GCB-16 in Room 2011)
Degradation of Pump 2P35A discharge test return upstream of 2SI-5A in Room 2011 during an independent demand (line 2GCB-16 in Room 2011)
Break Size:     Large                                         Isolabitity of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2011 Spatial Effects Comments: Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.
Large Isolabitity of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: SM-3.                                         System IWE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Room 2011 Spatial Effects Comments: Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.
Loss of Train:   TM-3                                         Train ID:               CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3.
System IWE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Category: MIEDIUM                     ["].       Consequence Rank                       11 Consequence Category: MEDIUM                   0               Consequence Rank                       0
Consequence Category: MIEDIUM
["].
Consequence Rank 11 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 27 of 40 Calculadon No. A-PENG-CALC-01S, Rv. 00 FMECA - Consequence Information Report 14-Sep-9                                                                                            Page A18 of A31 Consequence ED:. CSS-C-10B Consequence
Enclosure to CNRO-2007-00028 Page 27 of 40 FMECA - Consequence Information Report 14-Sep-9 Calcula don No. A-PENG-CALC-01S, Rv. 00 Page A18 of A31 Consequence ED:. CSS-C-10B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge test return upstream of 2SI-SB in Room 2011 during an independent demand (line 2GCBT17 in Room 2011)
Degradation of Pump 2P35B discharge test return upstream of 2SI-SB in Room 2011 during an independent demand (line 2GCBT17 in Room 2011)
Break Size:       Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occr during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagatio n                                   Effected Location:       Room 2011 Spatial Effects Comments: Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventry to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occr during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                            Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (MI) initiator is assumed to challenge this piping.
Spatial Effects: Propagatio Spatial Effects Comments:
Loss of System: SM-3                                           System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Initiating Event: N n
Loss of Train: TM-3                                             Train ID:               CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
Effected Location:
Room 2011 Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventry to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (MI) initiator is assumed to challenge this piping.
Loss of System: SM-3 System IPE ID:
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).
Consequence Category: MEDIUM                   F-1             Consequence Rank                     r]
Consequence Category: MEDIUM F-1 Consequence Rank r]
Consequence Category: MEDIUM                   0             Consequence Rank                       0
Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 28 of 40 FMECA - Consequence Information Report                                       CalculationNo. A-PENG-CALC-015,Rev. 00 14-Sep-9                                                                                           Page A19 of A31 Consequence ID: CSS-C-lIA Consequence
Enclosure to CNRO-2007-00028 Page 28 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-015,Rev. 00 14-Sep-9 Page A19 of A31 Consequence ID: CSS-C-lIA Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2055 during an independent demand (line 2GCB-16 in Room 2055)
Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2055 during an independent demand (line 2GCB-16 in Room 2055)
Break Size:       Large                                         Isolability of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2055 Spatial Effects Comments: There are no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and.
Large Isolability of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2055 Spatial Effects Comments: There are no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and.
propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                             System IPE ID:         CSS. HPSI, LPSI System Recovery: isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3                                           Train ID:             CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
CSS. HPSI, LPSI System Recovery: isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on' containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on' containment isolation.
Consequence Category: MEDUJM                                   'Consequence Rank                     11 Consequence Category: MEDIUM                   0               Consequence Rank                     0
Consequence Category: MEDUJM
'Consequence Rank 11 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 29 of 40 FMECA - Consequence Information Report                                     Calculation No. A-PENG-CALC-O)3, Rev. 00 14-Sep-9                                                                                           Page A20 of A31 Consequence ED: CSS-C-11B Consequence
Enclosure to CNRO-2007-00028 Page 29 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-O)3, Rev. 00 14-Sep-9 Page A20 of A31 Consequence ED: CSS-C-11B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2055 during an independent demand (line 2GCB-17 in Room 2055)
Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2055 during an independent demand (line 2GCB-17 in Room 2055)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                     Effected Location:   Room 2055 Spatial Effects Comments: There arc no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to be affected by this MCC.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2055 Spatial Effects Comments: There arc no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to be affected by this MCC.
Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment stunp recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment stunp recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                         -                System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to the assumed impact on MCC 2B52 before isolation, but containment cooling provides backup train.-
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3                                           Train El:             CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as described above.
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to the assumed impact on MCC 2B52 before isolation, but containment cooling provides backup train.-
Loss of Train:
TM-3 Train El:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as described above.
Consequence Comment: Consequence is '!Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and one backup train). The failure to isolate case is a "Medium" based on one backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is '!Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and one backup train). The failure to isolate case is a "Medium" based on one backup train (isolation). No impact on containment isolation.
Consequence Category: MIEDIUM                   13             Consequence Rank                     []
Consequence Category: MIEDIUM 13 Consequence Rank
Consequence Category: MEDIUM                     0               Consequence Rank                     0
[]
Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 30 of 40 FMECA - Consequence Information Report                                       Cakulation No. A-PENG-CAW-0L1, Rev. 00 14-Sep-9                                                                                           Page A21 of A31 Consequence ID: CSS-C-12A Consequence
Enclosure to CNRO-2007-00028 Page 30 of 40 FMECA - Consequence Information Report Cakulation No. A-PENG-CA W-0L1, Rev. 00 14-Sep-9 Page A21 of A31 Consequence ID: CSS-C-12A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge upstream of 2CV-5612 in Room 2084 during an independent demand (line 2GCB-16 in Room 2084)
Degradation of Pump 2P35A discharge upstream of 2CV-5612 in Room 2084 during an independent demand (line 2GCB-16 in Room 2084)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT- level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:   Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT-level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Propagation into Room 2040 where MCC 2B52 is located in the corridor. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 21362 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Propagation into Room 2040 where MCC 2B52 is located in the corridor. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 21362 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                             System IPE ID:       CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3 System IPE ID:
Loss of Train:. TM-3                                           Train ED:             CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:.
TM-3 Train ED:
CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Category: MEDIUM                       []           Consequence Rank                     0 Consequence Category: MEDIUM                   0               Consequence Rank                     0
Consequence Category: MEDIUM
[]
Consequence Rank 0
Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 31 of 40 FMECA - Consequence Information Report                                       Calycodon No. A-PENG-CALC-01S. Rev. 00 14-Sep-9                                                                                           Page A22 of A31 Consequence 11): CSS-C-12B Consequence
Enclosure to CNRO-2007-00028 Page 31 of 40 FMECA - Consequence Information Report Calycodon No. A-PENG-CALC-01S. Rev. 00 14-Sep-9 Page A22 of A31 Consequence 11): CSS-C-12B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge upstream of 2CV-5613 in Room 2084 during an independent demand (line 2GCB-17 in Room 2084)
Degradation of Pump 2P35B discharge upstream of 2CV-5613 in Room 2084 during an independent demand (line 2GCB-17 in Room 2084)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:   Room 2084 Spatial Effects Comments:, In Room 2084, the potential exists for spray impacts on RPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2084 Spatial Effects Comments:, In Room 2084, the potential exists for spray impacts on RPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                           System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-3                                         Train ID:             CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of Train:
TM-3 Train ID:
CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of
* challenge, between test exposure, and 1 backup train). The failure to isolate case is "Medium" based on I backup train (isolation). No impact on containment isolation.
* challenge, between test exposure, and 1 backup train). The failure to isolate case is "Medium" based on I backup train (isolation). No impact on containment isolation.
Consequence Category:, MEDIUM                                   Consequence Rank                     0]
Consequence Category:, MEDIUM Consequence Rank 0]
Consequence Category: MEDIUM                   0               Consequence Rank                     C
Consequence Category: MEDIUM 0
Consequence Rank C


Enclosure to CNRO-2007-00028 Page 32 of 40 FMECA - Consequence Information Report                                       CalculationNo. A-PENG-CAC-015. Rev. 00 14-Sep-9                                                                                            Page A23 of A31 Consequence ID: CSS-C-13A Consequence
Enclosure to CNRO-2007-00028 Page 32 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CAC-015. Rev. 00 Page A23 of A31 Consequence ID: CSS-C-13A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge downstream of 2CV-5612 in Room 2084 during an independent demand (line 2HCB-20)
Degradation of Pump 2P35A discharge downstream of 2CV-5612 in Room 2084 during an independent demand (line 2HCB-20)
Break Size:       Large                                           Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: PropagatioOn                                    Effected Location:     Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagatio Spatial Effects Comments:
Initiating Event: N On Effected Location:
Room 2084 In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                              Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                             System IPE ID:         CSS, HPSI, LPSI System Recovery; Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains in recirculation due to assumed impact on MCC 2B62 before isolation (discharge MOV 2CV-5613 is assumed to open prior to impact on MCC).
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-1                                           Train ID:             CSS A Train Recovery: Isolation success leads to loss of CSS train A, but containment cooling provides backup.
CSS, HPSI, LPSI System Recovery; Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains in recirculation due to assumed impact on MCC 2B62 before isolation (discharge MOV 2CV-5613 is assumed to open prior to impact on MCC).
Loss of Train:
TM-1 Train ID:
CSS A Train Recovery: Isolation success leads to loss of CSS train A, but containment cooling provides backup.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (uneixpcted frequency of challenge, all year exposure, and one backup train (isolation)) for failure to isolate case. The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5A provides containment isolation inside containment.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (uneixpcted frequency of challenge, all year exposure, and one backup train (isolation)) for failure to isolate case. The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5A provides containment isolation inside containment.
Consequence Category: MEDIUM                   III 3 III Consequence Rank                       11 Consequence Category: MEDIUM                   0               Consequence Rank                       0
Consequence Category: MEDIUM III III 3
Consequence Rank 11 Consequence Category: MEDIUM 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 33 of 40 FMECA - Consequence Information Report                                       CalculagionNo. A-PENG-CALC-01, Rev. 00 9                                                                                           Page A24 of A31 14-SeP Consequence ID: CSS-C-13B Consequence
Enclosure to CNRO-2007-00028 Page 33 of 40 FMECA - Consequence Information Report Calculagion No. A-PENG-CALC-01, Rev. 00 14-SeP 9 Page A24 of A31 Consequence ID: CSS-C-13B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge downstream of 2CV-5613 in Room 2084 during an independent demand (line 2HCB-21)
Degradation of Pump 2P35B discharge downstream of 2CV-5613 in Room 2084 during an independent demand (line 2HCB-21)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is-based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on HPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Large Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is-based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on HPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Propagation is into Room 2040 where MCC 2B52 is located in the corridor.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 an d 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: SM-3                                           System IPE ID:         CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Loss of System: SM-3 System IPE ID:
Loss of Train:   TM-I                                         Train ID:               CSS B Train Recovery: Isolation success leads to loss of CSS train B, but containment cooling provides backup.
CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and, I backup train for failure to isolate). The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5B provides containment isolation inside containment Consequence Category: MEDIUM                   11             Consequence Rank C
Loss of Train:
I1 Consequence Category: MEDIUM                   C               Consequence Rank
TM-I Train ID:
CSS B Train Recovery: Isolation success leads to loss of CSS train B, but containment cooling provides backup.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and, I backup train for failure to isolate). The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5B provides containment isolation inside containment Consequence Category: MEDIUM 11 Consequence Rank I1 Consequence Category: MEDIUM C
Consequence Rank C


Enclosure to CNRO-2007-00028 Page 34 of 40 FMECA - Consequence Information Report                                     Cal,-aIdon No A-PENIG-CALC-OIS. Rev. 00 14-Sep-9                                                                                           Page A25 of A31 Consequence ID: CSS-C-14A Consequence
Enclosure to CNRO-2007-00028 Page 34 of 40 FMECA - Consequence Information Report Cal,-aIdon No A-PENIG-CALC-OIS. Rev. 00 14-Sep-9 Page A25 of A31 Consequence ID: CSS-C-14A Consequence


== Description:==
== Description:==
Degradation of Pump 2P35A discharge downstream of 2CV-5612 inside containment during an independent demand (line 2HCB-3 upstream of 2BS5-SA)
Degradation of Pump 2P35A discharge downstream of 2CV-5612 inside containment during an independent demand (line 2HCB-3 upstream of 2BS5-SA)
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612. but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect except containment pressure may not reduced as fast as expected and train B is still available.
Break Size:
Spatial Effects: Containment                                   Effected Location:     Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event Initiating Event: N                                             Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612. but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect except containment pressure may not reduced as fast as expected and train B is still available.
Loss of System: N                                               System IPE ED:         N/A System Recovery: N/A Loss of Train:   N                                             Train ID:             N/A Train Recovery: Loss of CSS train A occurs only if the train is isolated by the operators. The train is still capable of performing its containment heat removal function.
Spatial Effects: Containment Effected Location:
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A &B).
Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event Initiating Event: N Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N System IPE ED:
N/A System Recovery: N/A Loss of Train:
N Train ID:
N/A Train Recovery: Loss of CSS train A occurs only if the train is isolated by the operators. The train is still capable of performing its containment heat removal function.
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).
2CV-5612 and closed system outside provide containment isolation.
2CV-5612 and closed system outside provide containment isolation.
Consequence Category: LOW                     01               Consequence Rank                     0
Consequence Category: LOW 01 Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 35 of 40 FMECA - Consequence Information Report                                     CalculationNo. A-PENG-CALC-015, Rev. 00 14-Sep79                                                                                         Page A26 of A31 Consequence ID: CSS-C-14B Consequence
Enclosure to CNRO-2007-00028 Page 35 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-015, Rev. 00 14-Sep79 Page A26 of A31 Consequence ID: CSS-C-14B Consequence


== Description:==
== Description:==
Degradation of Pump 2P35B discharge downstream of 2CV-5613 inside containment during an independent demand (line 2HCB-4 upstream of 2BS-5B)
Degradation of Pump 2P35B discharge downstream of 2CV-5613 inside containment during an independent demand (line 2HCB-4 upstream of 2BS-5B)
Break Size:     Large .                                       Isolability of Break. Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613, but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect exceptcontainment pressure may not reduced as fast as expected and train A is still available.
Break Size:
Spatial Effects: Containment'                                 Effected Location:     Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event.
Large.
Initiating Event: N                                           Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Isolability of Break. Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613, but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect exceptcontainment pressure may not reduced as fast as expected and train A is still available.
Loss of System: N                                             System WE ID:         N/A System Recovery: N/A Loss of Train:   N                                           Train ID:               N/A Train Recovery: Loss of CSS train B occurs only if the train is isolated by the operators. The train is still ca*able of performing its containment heat removal function.
Spatial Effects: Containment' Effected Location:
Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N System WE ID:
N/A System Recovery: N/A Loss of Train:
N Train ID:
N/A Train Recovery: Loss of CSS train B occurs only if the train is isolated by the operators. The train is still ca*able of performing its containment heat removal function.
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).
2CV-5613 and closed system outside provide containment isolation.
2CV-5613 and closed system outside provide containment isolation.
Consequence Category: LOW                     0               Consequence Rank                     0
Consequence Category: LOW 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 36 of 40 FMECA - Consequence Information Report                                         CalculationNo. A-PENG-C4LC-OIS, Rev. 00 14-Sep-9                                                                                            Page A27 of A31 Consequence ID: CSS-C-15A Consequence
Enclosure to CNRO-2007-00028 Page 36 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-C4LC-OIS, Rev. 00 Page A27 of A31 Consequence ID: CSS-C-15A Consequence


== Description:==
== Description:==
Degradation of NAOH line to Train A (line 2GCB-70) during an independent demand.
Degradation of NAOH line to Train A (line 2GCB-70) during an independent demand.
Break Size:       Large                                           Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagatio n                                     Effected Location:     Room 2014 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding of ECCS train A in Room 2014 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagatio Spatial Effects Comments:
Initiating Event:. N n
Effected Location:
Room 2014 Since this is a small line (2 inch diameter), flooding of ECCS train A in Room 2014 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.
Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the ECCS room.
Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the ECCS room.
Initiating Event:. N                                              Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N                                                 System IPE ID:         N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of System: N System IPE ID:
Loss of Train:     TM-3                                         ' Train ED:               CSS A, HPSI A, LPSI A Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS. thus, allowing recovery of HPSI and LPSI.
N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of Train:
TM-3
' Train ED:
CSS A, HPSI A, LPSI A Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS. thus, allowing recovery of HPSI and LPSI.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS B). Containment isolation is unaffected.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS B). Containment isolation is unaffected.
Consequence Category: MEDIUM                     13]             Consequence Rank                       1-1 Consequence Category: MEDIUM                     C               Consequence Rank                       0
Consequence Category: MEDIUM 13]
Consequence Rank 1-1 Consequence Category: MEDIUM C
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 37 of 40 FMECA - Consequence Information Report                                       CalculationNo. A-PENG-CAL-015, Rev. 00 14-Sep-9                                                                                             Page A28 of A31 Consequence IOD: CSS-C-15B Consequence
Enclosure to CNRO-2007-00028 Page 37 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CAL-015, Rev. 00 14-Sep-9 Page A28 of A31 Consequence IOD: CSS-C-15B Consequence


== Description:==
== Description:==
Degradation of NAOH line to Train B (line 2GCB-69) during an independent demand.
Degradation of NAOH line to Train B (line 2GCB-69) during an independent demand.
Break Size:       Large                                           Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                     Effected Location: Room 2007 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding of ECCS train B in Room 2007 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.
Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location: Room 2007 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding of ECCS train B in Room 2007 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.
Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is'provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train B must be assumed during the recirculation phase due to isolation,'otherwise, the containment sump would be emptied into the ECCS room.
Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is'provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train B must be assumed during the recirculation phase due to isolation,'otherwise, the containment sump would be emptied into the ECCS room.
Initiating Event: N                                               Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N                                                 System IPE ID:         N/A System Recovery, Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of System: N System IPE ID:
Loss of Train: - TW-3                                             Train ED:             CSS B, HPSI B, LPSI B Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS, thus, allowing recovery of -PSI and LPSI.
N/A System Recovery, Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of Train: - TW-3 Train ED:
CSS B, HPSI B, LPSI B Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS, thus, allowing recovery of -PSI and LPSI.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS A). Containment isolation is unaffected.
Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS A). Containment isolation is unaffected.
Consequence Category:       MEDIUM             13               Consequence Rank               .3   I Consequence Category: MEDIUM                   0                 Conseriucoce Rank                     0
Consequence Category: MEDIUM 13 Consequence Rank I
.3 Consequence Category: MEDIUM 0
Conseriucoce Rank 0


Enclosure to CNRO-2007-00028 Page 38 of 40 FMECA - Consequence Information Report                                       CalculationNo. A-PENG-CALC-01S. Rev. 00 14-Sep-9                                                                                           Page A29 of A31 Consequence ID: CSS-C-16 Consequence
Enclosure to CNRO-2007-00028 Page 38 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-01S. Rev. 00 14-Sep-9 Page A29 of A31 Consequence ID: CSS-C-16 Consequence


== Description:==
== Description:==
Degradation of RWT suction to SFPP and charging (line 2HCB-7) during an independent demand.
Degradation of RWT suction to SFPP and charging (line 2HCB-7) during an independent demand.
Break Size:     Large                                         Isolability of Break: No ISO Comments: Unisolable.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Outside Spatial Effects Comments: This piping is located both outside near the RWT and in Room 2040. Propagation from Room 2040 is down to El 317 (Rooms.2006 & 2011) through floor drains and east stairway. Detection is provided by auxiliary building sump high level alarm, but this is irrelevant since the break is unisolable. This line is judged too small (3 inch diameter) to divert enough of the RWT to cause flow diversion or loss of ECCS.
Large Isolability of Break: No ISO Comments: Unisolable.
Initiating Event: N                                           . Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagation Effected Location:
Loss of System: N     .;                                        System IPE ID:         N/A System Recovery: Pipe size is assumed too small to cause flow diversion or loss of ECCS.
Outside Spatial Effects Comments: This piping is located both outside near the RWT and in Room 2040. Propagation from Room 2040 is down to El 317 (Rooms.2006 & 2011) through floor drains and east stairway. Detection is provided by auxiliary building sump high level alarm, but this is irrelevant since the break is unisolable. This line is judged too small (3 inch diameter) to divert enough of the RWT to cause flow diversion or loss of ECCS.
Loss of Train:   N                                             Train ID:             N/A Train Recovery: N/A Consequence Comment: Consequence is '!Low" base on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).
Initiating Event: N  
. Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N System IPE ID:
N/A System Recovery: Pipe size is assumed too small to cause flow diversion or loss of ECCS.
Loss of Train:
N Train ID:
N/A Train Recovery: N/A Consequence Comment: Consequence is '!Low" base on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).
Containment isolation is unaffected.
Containment isolation is unaffected.
Consequence Category: LOW                     E)               Consequence Rank                     03
Consequence Category: LOW E)
Consequence Rank 03


Enclosure to CNRO-2007-00028 Page 39 of 40 FMAECA - Consequence Information Report                                     CalculationNo. A.PENG-CALC-0O5. Rev. 00 14-Sep-9                                                                                           Page A30 of A3)
Enclosure to CNRO-2007-00028 Page 39 of 40 FMAECA - Consequence Information Report Calculation No. A.PENG-CALC-0O5. Rev. 00 14-Sep-9 Page A30 of A3)
Consequence ID: CSS-C-17A Consequence
Consequence ID: CSS-C-17A Consequence


== Description:==
== Description:==
Degradation of service air connection to Train A (line 2HCB-93) during an independent demand.
Degradation of service air connection to Train A (line 2HCB-93) during an independent demand.
Break Size:     Large                                         Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagation                                   Effected Location:     Room 2084 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding impact is not assumed. Also.
Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Spatial Effects: Propagation Effected Location:
Room 2084 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding impact is not assumed. Also.
flow diversion impacts are not assumed. Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.
flow diversion impacts are not assumed. Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.
Initiating Event: N                                             Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N                                               System IPE ID:         N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of System: N System IPE ID:
Loss of Train:   T                                             Train ID:             CSS A Train Recovery: Isolation of CSS train during recirculation is required (2CV-5612). This allows HPSI A &
N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of Train:
T Train ID:
CSS A Train Recovery: Isolation of CSS train during recirculation is required (2CV-5612). This allows HPSI A &
LPSI A success. Also, containment cooling system can replace CSS A.
LPSI A success. Also, containment cooling system can replace CSS A.
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; -PSL LPSI, CSS B, and containment cooling). 2BS-SA provides containment isolation inside containment Consequence Category: LOW                     1"3               Consequence Rank                       []
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; -PSL LPSI, CSS B, and containment cooling). 2BS-SA provides containment isolation inside containment Consequence Category: LOW 1"3 Consequence Rank
Consequence Category: LOW                     0                 Consequence Rank                       0
[]
Consequence Category: LOW 0
Consequence Rank 0


Enclosure to CNRO-2007-00028 Page 40 of 40 FMECA - Consequence Information Report                                       CalculationNo. A-PENG-CALC-0i5, Rev. 00 14-Sep-9                                                                                             Page A31 of A31 Consequence ID: CSS-C-17B Consequence
Enclosure to CNRO-2007-00028 Page 40 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-0i5, Rev. 00 14-Sep-9 Page A31 of A31 Consequence ID: CSS-C-17B Consequence


== Description:==
== Description:==
Degradation of service air connection to Train B (line 2HCB-94) during an independent demand.
Degradation of service air connection to Train B (line 2HCB-94) during an independent demand.
Break Size:     Large                                           Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Break Size:
Spatial Effects: Propagatiopn                                    Effected Location:     Room 2084 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding impact is not assumed. Also, flow diversion impacts are not assumed- Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS B must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.
Large Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.
Initiating Event: N                                              Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Spatial Effects: Propagatio Spatial Effects Comments:
Loss of System: N                                               System WIE ID:         N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Initiating Event: N pn Effected Location:
Loss of Train:   T                                             Train ED:             CSS B Train Recovery: Isolation of CSS train during recirculation is required (2CV-5613). This allows HPSI B &
Room 2084 Since this is a small line (2 inch diameter), flooding impact is not assumed. Also, flow diversion impacts are not assumed-Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS B must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.
Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.
Loss of System: N System WIE ID:
N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).
Loss of Train:
T Train ED:
CSS B Train Recovery: Isolation of CSS train during recirculation is required (2CV-5613). This allows HPSI B &
LPSI B success. Also, containment cooling system can replace CSS B.
LPSI B success. Also, containment cooling system can replace CSS B.
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ret 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; HPSI. LPSI, CSS A, and containment cooling). 2BS-5B provides containment isolation inside containment.
Consequence Comment: Consequence is "Low" based on Table 2-2 of Ret 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; HPSI. LPSI, CSS A, and containment cooling). 2BS-5B provides containment isolation inside containment.
Consequence Category: LOW                           0           Consequence Rank                       11 Consequence Category: LOW                       0               Consequence Rank                       0}}
Consequence Category: LOW 0
Consequence Rank 11 Consequence Category:
LOW 0
Consequence Rank 0}}

Latest revision as of 22:26, 14 January 2025

Request for Alternative ANO2-R&R-004, Revision 1, Response to NRC Request for Additional Information
ML072220160
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 08/06/2007
From: Mccann J
Entergy Operations
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
CNRO-2007-00015, CNRO-2007-00028
Download: ML072220160 (44)
v • d • e


Text

nteigy Entergy Operations, Inc.

1340 Echelon Parkway Jackson, Mississippi 39213-8298 Tel: 601-368-5758 John F. McCann Director, Nuclear Safety & Licensing CNRO-2007-00028 August 6, 2007 U. S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555-0001

SUBJECT:

Request for Alternative ANO2-R&R-004, Revision 1 Response to NRC Request for Additional Information Arkansas Nuclear One, Unit 2 Docket No. 50-368 License No. NPF-6

REFERENCE:

Entergy Operations, Inc letter CNRO-2007-00015 to the NRC dated April 17, 2007

Dear Sir or Madam:

Per the referenced letter, Entergy Operations, Inc. (Entergy) submitted Request for Alternative ANO2-R&R-004, Rev. 1, which requested the NRC staff's authorization to implement a risk-informed safety classification (RISC) process for repair/replacement activities in Class 2 and 3 moderate energy systems at Arkansas Nuclear One, Unit 2 (ANO-2). In its review of the request, the NRC staff requested that Entergy provide a test case, or example, that demonstrates the RISC process. Entergy is providing the requested example in the enclosure to this letter to support the staffs review. Following approval of ANO2-R&R-004, Rev. 1, any specific application of this process to a plant system Would be initiated and controlled in accordance with appropriate engineering programs.

In addition to submitting the requested example, Entergy revises the need date for ANO2-R&R-004, Rev. 1 to April 17, 2008. Should you have any questions regarding this submittal, please contact Guy Davant at (601) 368-5756.

This letter contains no commitments.

JFM/GHD/ghd

Enclosure:

Application of Risk-Informed Safety Classification Process for Repair/Replacement Activities in Class 2 and 3 Moderate Energy Systems kL)6ý

CNRO-2007-00028 Page 2 of 2 cc:

Mr. J. S. Forbes (ECH)

Mr. 0. Limpias (WPO)

Mr. T. G. Mitchell (ANO)

Dr. Bruce S. Mallett U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 U. S. Nuclear Regulatory Commission Attn: Mr. Alan Wang MS O-7D1 Washington, DC 20555-0001 NRC Senior Resident Inspector Arkansas Nuclear One P.O. Box 310 London, AR 72847

CNRO-2007-00028 bcc:

Mr. W. B. Abraham (G-ADM2-LIC)

Mr. C. A. Bottemiller (G-ADM2-LIC)

Mr. W. B. Brice (M-ECH-521)

Mr. J. J. Costedio (K-JAF-H145)

Mr. A. Y. Eng (K-WPO-12C)

Ms. C. D. Faison (K-WPO-12C)

Ms. S. T. Fontenot (W-GSB-318)

Mr. B. S. Ford (M-ECH-521)

Mr. K. W. Hall (M-ECH-36)

Mr. D. E. James (N-GSB-64)

Mr. R. S. Lewis (M-ECH-36)

Mr. D. N. Lorfing (R-GSB-42)

Ms. K. A. Maher (R-GSB-42)

Mr. D. J. Mannai (V-VYP-1 03)

Mr. R. J. Murillo (W-GSB-318)

Mr. D. J. Ropson (K-WPO-11 D)

Ms. K. K. U. Tom ((K-JAF-H716)

Ms. D. S. Waldron (N-GSB-64)

Mr. R. W. Walpole (K-IP-GSB2E)

Echelon Information Management File [54]

ENCLOSURE CNRO-2007-00028 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY SYSTEMS

Enclosure to CNRO-2007-00028 Page lof40 APPLICATION OF RISK-INFORMED SAFETY CLASSIFICATION PROCESS FOR REPAIR/REPLACEMENT ACTIVITIES IN CLASS 2 AND 3 MODERATE ENERGY PIPING SYSTEMS I.

OVERVIEW This document package contains an example application of the risk-informed safety classification (RISC) process to be applied to repair/replacement activities in Class 2 and 3 moderate energy piping systems. This process was submitted to the NRC staff for approval by Entergy Operations, Inc. (Entergy) as Request for Alternative ANO2-R&R-004, Rev. i via letter CNRO-2007-00015 dated April 17, 2007. The RISC process was developed by EPRI and is founded upon the EPRI risk-informed inservice inspection (RI-ISI) evaluation procedure (EPRI TR-1 06706, Rev B-A).

The NRC granted Arkansas Nuclear One, Unit 2 (ANO-2) approval to implement what, is known as a full-scope RI-ISI program [i.e., Class 1, 2, and some 3 / non-nuclear safety (NNS) piping] using the EPRI RI-ISI procedure.' As such, the vast majority of the information necessary to support the repair/replacement relief request already exists.

The final piece of the process is what is termed "the additional considerations', which consists of a series of questions that supplement the consequence evaluation that was previously developed as part of the RI-ISI application. These additional considerations were addressed by developing draft responses and conducting an interdisciplinary review during a-meeting held on July 12, 2007 at the ANO site.

II.

APPLICATION As requested by the NRC, Entergy has developed this example application of the RISC process by applying it to the Containment Spray System (CSS).2 The CSS evaluation does not credit the Containment Cooling System (CCS), which provides another means of containment heat removal independent of CSS. As such, the consequence rank identified herein is conservative for a numberof segments. However, the rank of high-ranked segments would not change since failure of these segments typically results in a loss of Emergency Core Cooling Systems (ECCS) and/or a containment bypass potential.

Table 1, below, is taken from the RI-ISI evaluation for CSS with one modification being to ID

  1. s CSS-C-17A and -17B, which no longer credit CCS as available backup. 3 Figures 1 and 2, also taken from the RI-ISI evaluation, provide simplified piping diagrams of CSS.

1 The NRC's approval is documented in a letter to ANO-2 dated December 29,1998.

2 Any specific application of this process to a plant system would be initiated and controlled in accordance with appropriate engineering programs.

3 Entergy submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.

Enclosure to CNRO-2007-00028 Page 2 of 40 TABLE 1 CSS Consecluence Assessment Summary Decito

-Spatial Cnguain Itaor slton

-System.

AalbeEpsr TbeUed Rank ID *

'Descripion

^.,.

Configum-tior i Initiator a-

.Ioaion'*.-

Backup Containment ',

Tm N t l=:*":

I

-Location.

IsP t, Impacts ckp Cnamet Time (Note 1 Trains CSS-C-01 Common RWT Outside Demand Assumed No CSS, HPSI, 0

Unaffected between 2-2 HIGH suction outside M

LPSI test CSS-C-02 Common RWT Assumed No CSS, HPSI, Unaffected between 2-2 HIGH suction inside 2040 Demand M

LPSI test CSS-C-03A RWT suction A 2040 Demand Assumed 2CV-5630 ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM in 2040 M

all ECCS isolation) test CSS-C-03B RWT suction B Assumed 2CV-5631 all ECCS &

Unaffected between 2-2 HIGH in 2040 2040 Demand M

CSS test CSS-C-04A RWT suction A Assumed 2CV-5630 ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM in scin 2014 Demand M

all ECCS isolation) test CSS-C-04B RWT-suction B 2007 Demand Assumed 2CV-5631 ECCS B o.

1 (ECCS A or Unaffected between 2-2 MEDIUM in 2007 M

all ECCS isolation) test CSS-C-05 RWT suction B 2006 Demand Assumed 2CV-5631 ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM in 2006 eM all ECCS isolation) test.

CSS-C-06A Sump suction Assumed 2CV-5647 ECCS Ao.r 1 (ECCS B or Bypass if Isol all year 2-2 HIGH A in 2014 M

all ECCS isolation) fails CSS-C-06B Sump suction Assumed ECCS B 2r 1 (ECCS A or Bypass if Isol B in 2007 2007 Demand M

all ECCS isolation) fails 2P-35A Assumed Trip pump &

ECCS A or 1 (ECCS B or between 2-2 MEDIUM CSS-C-07A discharge to 2014 Demand M

2CV-5630 all ECCS isolation)

Unaffected test 2E35A 2P35B Assumed Trip pump &

ECCS B or 1 (ECCS A or between CSS-C-07B discharge to 2007 Demand Unaffected t2-2 MEDIUM 2E35B M

2CV-5631 all ECCS isolation) test 2P-3A mii Asume Trp pup &between CSS-C-08A 2P-35A mini 2014 Demand Assumed Trip pump &

CSS A 1 (CSS B.

Unaffected between 2-2 MEDIUM flow M

2CV-5630 test CSS-C-08B 2P35B mini Assumed Trip pump &

CSS B 1 (CSS Al)

Unaffected between 22 MDU flow 2007 Demand M

2CV-5631 test 22 MDU

Enclosure to CNRO-2007-00028 Page 3 of 40 Spatialpt System AalbeExposure Table Used

..ID Description Laon Configuration Initiator liolation

.I.mpacts Backup Containment Time i

(Nblet1)

Rank Trainsý CSS-C-09A Downstream of Assumed Trip pump &

ECCS A or 1 (ECCS B or between 2-2 MEDIUM 2E35A in 2014 2014 Demand M

2CV-5630 all ECCS isolation)

Unaffected test CSS-C-09B Downstream of 2007 Demand Assumed Trip pump &

ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM 2E35B in 2007 M

2CV-5631 all ECCS isolation) test CSS-C-1 OA 2P-35A test 2011 Demand Assumed Trip pump &

ECCS A f 1 (ECCS B or Unaffected between 2-2 MEDIUM return in 2011 M

2CV-5630 all ECCS isolation) test CSS-C-10B 2P35B test 2011 Demand Assumed Trip pump &

ECCS B or 1 (ECCS A or between return in 2011 M

2CV-5631 all ECCS isolation)

Unaffected test 2-2 MEDIUM CSS-C-11A Downstream of 2055 Demand Assumed Trip pump &

- ECCS A or 1 iECCS B or Unaffected between 2-2 MEDIUM 2E35A in 2055 M

2CV-5630 all ECCS isolation) test CSSýC-11B Downstream of 2055 Demand Assumed Trip pump &

ECCS B or 1 (ECCS A or between 2-2 MEDIUM 2E35B in 2055 M

2CV-5631 all ECCS isolation)

Unaffected test Upstream of CSS-C-12A 2CV-5612 in 2084 Demand Assumed Trip pump &

ECCS A or 1 (ECCS B or Unaffected between 2-2 MEDIUM 2084 M

2CV-5630 all ECCS isolation) test Upstream of CSS-C-12 U

2CV-5613 in 2084 Demand Assumed Trip pump &

ECCS B or 1 (ECCS A or Unaffected between 2-2 MEDIUM 2

2084 M

2CV-5631 all ECCS isolation) test Downstrea of CSS-C-13A 2CV-5612 in 2084 Demand Assumed Trip pump &

CSS A or 1 (CSS B or 2BS-5A all year 2-2 MEDIUM 2

2084 M

2CV-5612 all ECCS isolation) inside Downstream of CSS-C-13B 2CV-5613 in 2084 Demand Assumed Trip pump &

CSS B or 1 (CSS A or 2BS-5B all year 2-2 MEDIUM 2

2084 M

2CV-5613 all ECCS isolation) inside Downstream of 2CV-5612 CSS-C-14A 2CV-5612 in Containment Demand Assumed Trip pump &

none 2

and closed all year 2-2 LOW.

Containment M

2CV-5612 system outside Downstream of 2CV-5613 CSS-C-14B 2CV-5613 in Containment Demand Assumed Trip pump &

none 2

and closed all year 2-2 LOW Containment M

2CV-5613 system outside CSS-C-15A NaOH to Train 2014 Demand Assumed Trip pump &

ECCS A 1 ECCS B Unaffected between 2-2 MEDIUM A

2 D

M 2CV-5630 E

A 1

test

Enclosure to CNRO-2007-00028 Page 4 of 40 Note 1: Tables contained in Yankee Nuclear services Division Calculation No. NSD-018, Rev. 0, August 1997, Consequence Evaluation of ANO-2 EFW, Containment Spray, and Main Steam and Feedwater System Piping, Arkansas Nuclear 1, Unit 2 Note 2: Segments 18A and 18B were not part of the original RI-ISI application (i.e., not within ASME Section Xl scope). Postulated failures of these segments have the same impact as segments 14A and 14B.

Enclosure to CNRO-2007-00028 Page 5 of 40 R e fu e lin g

" - ------------- C-S-C----

Water CS.......

CSS-C-04A CSSC-1 Ko z~o::

luds'InluesSuucio t

A Outside0-.Ro 2040 2CV-5649-1

.2P60A (LPS,

':...... --:........-5 i.............

(H28 9PH S I) &......

2CV490-2P89 chrig 2CV 5647 I"

CSS-C-06A Outside 2B S-2Pump R-oom2014 CS- -C5420

,~2C 5648-250-Room 2040 Containment--.-----65,-"

CSS-C-04B S.tinludes Suction to 2P60B (LPSI) &

Root.2040 I

2P89B (LPS1) 2CV-5649-c CSS-C-03B 6CSS'C-05

-06A Room 2 Rm2 Room 2007

Enclosure to CNRO-2007-00028 Page 6 of 40 S.

CSS-C-15A css-c-10A CSS-CC-IOB 2BS-12A Room 2007 Roo 201 i

2I-5A RWT

~~~2B S-44A *,

.o R oo css-c-O7 FO F

R Rom 2014 B*S AL M

I Room 2014 CSS-C-08A

  • 2Room2014 mini flow 2BS-17A CV-56973-1 CSS-C-15B

" Room 2007 i"

2 B S

-12 B 2 S*......

o m O 7I-5 B R W T LPCI he

,,2BS-44Bi l

  • om20*

i

  • css-,

S CSS-C-07B F

Roon Room 2007*,hlIF 2BS4 CSS-C-09B

{

2P3 ;B lRoom 2007

/t **

Enclosure to CNRO-2007-00028 Page 7 of 40 III.

ADDITIONAL CONSIDERATIONS Piping segments that were determined to be a "Medium", "Low", or "None" consequence category per the consequence evaluation are determined to be high safety significant (HSS) or low safety significant (LSS) by considering the information in Conditions (1) through (10),

below.

Note: Although a large pressure-boundary leak is not always assumed, it was during the RI-ISI evaluations. Also, credit may be taken for plant features and operator actions to the extent these would not be affected by failure of the segment under consideration. If plant features and operator actions are credited, they shall be consistent with those credited in the previous consequence evaluations.

(1)

Failure of the pressure-retaining function of the segment will not directly or indirectly (e.g., through spatial effects) fail a basic safety function.

Response

Per Table I above, any segment classified as "Medium" or "Low"will have at least one train unaffected by the postulated break. Per the glossary, loss of a single train would typically not constitute loss of a basic function.

(2)

Failure of the pressure-retaining function of the segment will not prevent the plant from reaching or maintaining safe shutdown conditions; and the pressure-retaining function is not significant to safety during mode changes or shutdown. Assume that the plant would be unable to reach or maintain safe shutdown conditions if a pressure boundary failure results in the need for actions outside of plant procedures or available backup plant mitigative features.

Response

Although the CSS can be used to support shutdown [e.g., as an altemative to Low Pressure Safety Injection (LPSI) pumps, the Reactor Water Tank (RWT) provides inventory for filling the refueling canal], the CSS is typically not used to support mode changes or shutdown cooling. Per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. In addition, the consequence evaluation methodology includes an assessment of piping failure during shutdown evolutions.

(3)

The pressure-retaining function of the segment is not called out or relied upon in the plant Emergency/Abnormal Operating Procedures (EOPs) or similar guidance as the sole means for successfully performing Operator actions required to mitigate an accident or transient.

Response

While CSS is credited in the EOPs, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium" or

Enclosure to CNRO-2007-00028 Page 8.of 40 "Low") are not the sole means for successfully performing operator actions required to mitigate an accident or transient.

(4)

The pressure-retaining function of the segment is not called out or relied upon in the plant EOPs or similar guidance as the sole means for assuring long-term containment integrity, monitoring of post-accident conditions, or offsite emergency planning activities.

Response

While CSS is credited in the EOPs, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such, these segments (i.e., those categorized as "Medium" or "Low") are not the sole means for assuring long-term containment integrity. Additionally, the containment coolers provide an altemate means of containment cooling and the CSS does not provide a post-accident monitoring function or offsite emergency planning function.

(5)

Failure of the pressure-retaining function of the segment will not result in an unintentional release of radioactive material that would result in implementing offsite radiological protective actions.

Response

Failure of the CSS will not cause such events. Rather, the function of the CSS is to respond to such events (e.g., LOCAs). Additionally, per the consequence evaluations conducted above, any segment classified as "Medium" or "Low" will have at least one train unaffected by the postulated break. As such; the design basis function of the CSS will still be fulfilled.

The RISC process shall demonstrate that the defense-in-depth philosophy is maintained.

Defense-in-depth is maintained if:

(6)

Reasonable balance is preserved among prevention of core damage, prevention of containment failure or bypass, and mitigation of an offsite release.

Response

This balance is preserved as there' is no change to the design, design basis, or operation of the CSS by this change. The CSS is still required to reliably perform its safety-related function.

(7)

There is no over-reliance on programmatic activities and operator actions to compensate for weaknesses in the plant design.

Response

The consequence evaluation conducted reflects the as-operated/as-designed plant.

This evaluation does not increase the reliance on programmatic activities or operator actions. Operator actions, when credited, are credited consistent with the approved RI-ISI consequence evaluation methodology.

Enclosure to CNRO-2007-00028 Page 9 of 40 (8)

System redundancy, independence, and diversity are preserved commensurate with the expected frequency of challenges, consequences of failure of the system, and associated uncertainties in determining these parameters.

Response

System redundancy, independence, and diversity are preserved since there is no change to the design, design basis, or operation of the CSS by this change. The CSS will still be required to reliably perform its safety-related function.

(9)

Potential for common cause failures is taken into account in the risk analysis categorization.

Response

Yes, "common cause" is a fundamental aspect of the consequence evaluation methodology and, therefore, is taken into account (e.g., see Table 1-2 of ANO2-R&R-004, Rev. 1).

(10) Independence of fission-product barriers is not degraded.

Response

Independence of fission barrier is not degraded since no new dependencies have been created. The CSS is still required to reliably perform its safety-related function.

If any of the above ten (10) conditions are not true, then HSS shall be assigned. Otherwise, LSS is assigned.

Based upon the above, segments assigned to "Medium" or "Low" consequence rank do not have to be moved into the high consequence rank and can be assigned as "LSS" provided "safety margin" is adequately addressed below.

IV. SAFETY MARGINS As a final step, the RISC process verifies that there are sufficient safety margins to account for uncertainty in the engineering analysis and in the supporting data. Safety margin is incorporated when determining performance characteristics and parameters; e.g., piping segment, system, and plant capability or success criteria. The amount of margin should depend on the uncertainty associated with the performance parameters in question, the availability of alternatives to compensate for adverse performance, and the consequences of failure to meet the performance goals. Sufficient safety margins are maintained by ensuring that safety analysis acceptance criteria in the plant licensing basis are met, or proposed revisions account for analysis and data uncertainty.

Response

Since the safety analysis acceptance criteria in the plant licensing basis are not changed, safety margins remain unchanged and, therefore, acceptable.

Enclosure to CNRO-2007-00028 Page 10 of 40 Based upon all the preceding factors a final RISC for the CSS has been determined. These results are provided in Table 2.

TABLE 2 Final RISC Assiqnments ID Description Spatial Location Rank CSS-C-01 Common RWT suction outside Outside HIGH CSS-C-02 Common RWT suction inside 2040 HIGH CSS-C-03A RWT suction A in 2040 2040 LOW CSS-C-03B RWT suction B in 2040 2040 HIGH CSS-C-04A RWT suction A in 2014 2014*

LOW CSS-C-04B RWT suction B in 2007 2007 LOW CSS-C-05 RWT suction B in 2006 2006 LOW CSS-C-06A Sump suction A in 2014 2014 HIGH CSS-C-06B Sump suction B in 2007 2007 HIGH CSS-C-07A 2P-35A discharge to 2E35A 2014 LOW CSS-C-07B 2P35B discharge to 2E35B 2007 LOW CSS-C-08A 2P-35A mini flow 2014 LOW CSS-C-08B 2P35B mini flow 2007 LOW CSS-C-09A Downstream of 2E35A in 2014 2014 LOW CSS-C-09B Downstream of 2E35B in 2007 2007 LOW CSS-C-10A 2P-35A test return in 2011 2011 LOW CSS-C-10B 2P35B test return in> 2011 2011 LOW CSS-C-11A Downstream of 2E35A in 2055.

2055 LOW CSS-C-1 1 B Downstream of 2E35B in 2055 2055 LOW CSS-C-12A Upstream of 2CV-5612 in 2084 2084 LOW CSS-C-12B Upstream of 2CV-5613 in 2084 2084 LOW CSS-C-13A Downstream of 2CV-5612 in 2084 2084 LOW CSS-C-13B Downstream of 2CV-5613 in 2084 2084 LOW CSS-C-14A Downstream of 2CV-5612 in Containment Containment LOW CSS-C-14B Downstream of 2CV-5613 in Containment Containment LOW CSS-C-15A NaOH to Train A 2014 LOW CSS-C-1 5B NaOH to Train B 2007 LOW CSS-C-1 6 RWT to SFPP & charging Outside 2040 LOW CSS-C-17A Service air connection to Train A 2084 LOW

Enclosure to CNRO-2007-00028 Page 11 of 40 I D Description.

Spatial Location Rank CSS-C-17B Service air connection to Train B 2084 LOW CSS-C-1 8A Downstream of 2BS-5A in Containment Containment LOW CSS-C-1 8B Downstream of 2BS-5B in Containment Containment LOW V.

CONSEQUENCE INFORMATION REPORTS The Consequence Information Reports, which were developed for the ANO-2 RI-ISI program, summarize the consequence evaluation process. 4 As noted earlier, the CSS evaluation did not credit the Containment Cooling System (CCS). As such, the consequence rank identified herein is conservative for a number of segments. However, the rank for high-ranked segments would not change since failure of these segments typically results in a loss of all ECCS and / or a containment bypass potential.

FMECA - Consequence Information Report Calculation No. A-PENG.CALC-015. Rev. 00 14-Sep-9 Page A2 of A31 Consequence ID: CSS-C-01 Consequence

Description:

Degrdation of common RWT suction outside auxiliary building during an independent demand (line 2HCB-24 outside)

Break Size:

Large Isolability of Break. No ISO Comments: Unisolable.

Spatial Effects: Local Effected Location:

Outside Spatial Effects Comments: The common RWT suction piping outside the auxiliary building (near the RWT) can not propagate to the auxiliary building and impact safety equipment' Initiating Event:' N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,

demand stress of RWT head is not significantly different during demand).

Loss of System: SM-3 System IPE MD:

CSS, HPSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.

Loss of Train:

N Train ID:

N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.

Consequence Category: HIGH 03 Consequence Rank 0

4 Entergy submitted the ANO-2 RI-ISI application, which included the Consequence Information Reports, to the NRC via letter 2CAN099706 dated September 30, 1997.

Enclosure to CNRO-2007-00028 Page 12 of 40 FMECA - Consequence Information Report Calculat-,n No. A-PENG-CALC-O15. Rev. 00 14-Sep-9 Page A3 of A31 Consequence ID: CSS-C-02 Consequence

Description:

Degradation of common RWT suction upstream of 2CV-5630 & 5631 in auxiliary building during an independent demand (line 2HCB-24 in auxiliary building)

Break Size:

Large ISO Comments: Unisolable.

Isolability of Break: No Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N n

Effected Location:

Room 2040 The common RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 201 1) through floor drains and the east stairway. Also, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014). Detection is provided by auxiliary building sump high level alarm and the ECCS room flood alarms in the control room, but this is irrelevant since the break is unisolable.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,

demand stress of RWT head is not significantly different during demand).

Loss of System: SM-3 System IPE ED:

CSS, -PSI, LPSI System Recovery: Loss of RWT (flow diversion) results in common cause failure of all ECCS.

Loss of Train:

N Train ID:

N/A Train Recovery: N/A Consequence Comment: Consequence is "High" based on Table 2-2 of RIf 9.18 (unexpected frequency of challenge, between test exposure, and no backup trains). No impact on containment isolation.

Consequence Category: FUGH 13 Consequence Rank 1:1 Consequence Category: HIGH 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 13 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG*CALC-0)5. Rev. 00 14-Sep-9 Page A4 of A31 Consequence ID: CSS-C-03A Consequence

Description:

Degradation of RWT suction A downstream of 2CV-5630 in Room 2040 during an independent demand (line 2HCB-26 in Room 2040)

Break Size:

Large Isolabifity of Break: Yes ISO Comments: 2CV-5630-1 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2040 Spatial Effects Comments: RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV.

5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.

Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,

demand stress of RWT head is not significantly different during demand).

Loss of System: SM.3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train El):

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium, based on I backup train (isolation). No impact on containment isolation.

Consequence Category: MEDIUM Consequence Rank r'

Consequence Category: MEDIUM El Consequence Rank C

Enclosure to CNRO-2007-00028 Page 14 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculafton No. A-PENG-CALC-0)5. Rev. 00 Page A5 of A31 Consequence ED: CSS-C-03B Consequence

Description:

Degradation of RWT suction B downstream of 2CV-5631 in Room 2040 during an independent demand (line 214CB-27 in Room 2040)

Bre"k Size:

Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWTIevel alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N n

Effected Location:

Room 2040 RWT suction piping will likely fail MCC 2B52 in the corridor at El 335 (Room 2040) and propagate to El 317 (Rooms 2006 & 2011) through floor drains and the east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.

Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,

demand stress of RWT head is not significantly different during demand).

Loss of System: SM-3 System IPE ID:

CSS, HPSI LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to assumed impact on MCC 2B52 before isolation. Normally closed 2CV-5612-1 can not fully open for train A success due to flood impact on its breaker in MCC2B52.

Loss of Train:

TM-2 Train ED:

HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as shown above.

Consequence Comment: Consequence is "High" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and no backup train). No impact on containment isolation.

Consequence Category: FUGH El Consequence Rank E]

Consequence Category: HIGH 0

Consequence Rank C

Enclosure to CNRO-2007-00028 Page 15 of 40 FMECA - Consequence Information Report Calculadon No. A-PENG-CALC-015, Rev. 00 14-Sep-9 Page A6 of A3)

Consequence ID: CSS-C-04A Consequence

Description:

'Degradation of Suction A downstream of 2CV-5630 & 2CV-5649 in Room 2014 during an independent demand (lines 2HCB-26 and 2HCB-15 downstream of 2CV-5649 in Room 2014)

Break Size:

Large'.

Isolability of Breiak Yes ISO Comments: 2CV-5630-1 can be closed from the control room (break is assumed to occur during RWIT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm'if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2014 Spatial Effects Comments: RWT suction piping will likely flood ECCS train A in Room 2014 before isolation.

Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2007 (ECCS train B).

However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA CM) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,

demand stress of RWT head is not signficantly different during demand).

Loss of System: SM-3.

System IPE ID:

CSS, -PSI, LPS1 System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train iD:

CSS A, HPSI A, LPSI A Train Recovery; Isolation success leads to loss of ECCS train A.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.

Consequence Category: lffiDrLJM 13,

Consequence Rank 13 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 16 of 40 FMECA - Consequence Information Report, Calculation No. A-PENG-CALC-0Z5, Rev. 00 14-Sep-9 Page A7 of A31 Consequence ID: CSS-C-04B Consequence

Description:

Degradation of Suction B downstream of 2CV-5631 & 2CV-5650 in Room 2007 during an independent demand (lines 2HCB-27 and 2HCB-13 downstream of 2CV-5650 in Room 2007)

Break Size:

Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed fi-om the control room (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2007 Spatial Effects Comments: RWT suction piping will likely flood ECCS train B in Room 2007 before isolation.

Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood Room 2014 (ECCS train A).

However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may bejust as likely (i.e.,

demand stress of RWT head is not signficantly different during demand).

Loss of System: SM-3.

System WPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion or insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). No impact on containment isolation.

Consequence Category: MEDIUM 11 Consequence Rank

[]

Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 17 of 40 FMECA - Consequence Information Report Calklatiwi No. A-PENG-C4LC-O)5. Rev. O0 14-Sep-9 Page A8 of A31 Consequence ID: CSS-C-05 Consequence

Description:

Degradation of RWT suction B downstream of 2CV-5631 in Room 2006 during an independent demand (line 2HCB-27 in Room 2006)

Break Size:

Large Isolability of Break: Yes ISO Comments: 2CV-5631-2 can be closed from the control room. Detection is based on auxiliary building sump high level alarm and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2006 Spatial Effects Comments: Failure to isolate is assumed to propagate into ECCS Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on an SI signal.

Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level'alarm in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi) initiator is assumed to challenge this piping. This is conservative since pipe break during normal standby may be just as likely (i.e.,

demand stress of RWT head is not significantly different during demand).

Loss of System: SM-3 System IPE ID:

CSS, HPS!, LPSI System.Recovery: Isolation failure is assumed to fail all ECCS either due to flow diversion, flooding, or insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ED:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.

Consequence Category: MEDIUM Consequence Rank 0.

Consequence Category: MEDIUM D

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 18 of 40 FMECA - Consequence Information Report Calculaton No:A-PENG-CALC-01. Rev. 00 I4-Sep-9 Page 'A9 of A31 Consequence ID: CSS-C-06A Consequence

Description:

Degradation of containment sump suction A upstream of 2CV-5649 during an independent demand (line 2HCB-15 from containment sump to 2CV-5649)

Break Size:

Large Isolability of Break: Yes ISO Comments: 2CV-5647-1 can be closed from the control room. Detection is based on Room 2014 flood alarm and auxiliary building sump level.

Spatial Effects: Propagation Effected Location:

Room 2014 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train A in Room 2014 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.

Detection is provided by Room 2014 flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).

Loss of Train:

TM-3 Train ID:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A recirculation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and.1 backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5647-1 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18)

Consequence Category: HIGH 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 19 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CALC-O)5, Rev. 00 Page AIO of AS)

Consequence EID: CSS-C-06B Consequence

Description:

Degradation of containment sump suction B upstream of 2CV-5650 during an independent demand (line 2HCB-13 from containment sump to 2CV-5650)

Break Size:

Large I olability of Break: Yes ISO Comments: 2CV-5648-2 can be closed from the control room. Detection is based on Room 2007 flood alarm and auxiliary building sump level.

Spatial Effects: Propagation.

Effected Location:

Room 2007 Spatial Effects Comments: Containment sump suction piping will likely flood ECCS train B in Room 2007 before isolation. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings and draining the sump into the auxiliary building.

Detection is provided by Room 2007 flood and auxiliary.building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSL LPSI System Recovery: Isolation failure case is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).

Loss of Train:

TM-3 '

Train ID:

CSS B, -PSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B recirculation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" based on 1 backup train (isolation). The consequence is upgraded to "High" because piping failure together with failure to isolate (MOV 2CV-5648-2 failure to close) can result in containment bypass (Table 2-4 of Ref. 9.18).

Consequence Category; lUGH 0

Consequence Rank 13 Consequence Category: HIGH 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 20 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG-CALC-0IS, Rev. 00 14-Sep-9 Page All of AS)

Consequence ID: CSS-C-07A Consequence

Description:

Degradation of Pump 2P35A discharge to heat exchanger 2E35A during an independent demand (line 2GCB-10)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWr (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxilhazy building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventosy to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ED:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation).

Consequence Category: MEDIUM F-1 Consequence'Rank E3 Consequence Category: MEDIIJM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 21 of 40 FMECA - Consequence Information Report CalculaionvNo.A-PENG-CALC-OJ5, Revp 00 14-Sep-9 Page A12 of A31 Consequence ID: CSS-C-07B Consequence

Description:

Degradation of Pump 2P35B discharge to heat exchanger 2E35B during an independent demand (line 2GCB-11)

Break Size:

Large Isolahility of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2007 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump-recirculatian. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

.. CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).

Consequence Category: MEDIUM Consequence Rank E3 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 22 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CALC-015, S. Rn, 0

Page A)3 of A31 Consequence ID: CSS-C-08A Consequence

Description:

Degradation of Pump 2P35A mini flow in Room 2014 during an independent demand (line 2GCB-35 and line 2DCB-11 upstream of 2CV-5673 in Room 2014)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2A in Room 2014 which would allow operation of HPSI A and LPSI A without further leakage into the room. Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N n

Effected Location:

Room 2014 Flooding is assumed to affect train A ECCS in Room 2014 if not isolated. Another oppommity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5647 or 2CV-5649 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to lead to loss of containment sump (common cause failure of ECCS recirculation).

Loss of Train:

TM-3 Train ID:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of only CSS train A. Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train A due to flooding in the room.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup trains - CSS B in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS B or 2 isolations).

Consequence Category: MEDFJM 11, Consequence Rank 1-1 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 23 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG.CAL. -015, Rev. 00 Page AU4 of AR)

Consequence ID: CSS-C-08B Consequence

Description:

Degradation of Pump 2P35B mini flow in Room 2007 during an independent demand (line 2GCB-34 and line 2DCB-13 upstream of 2CV-'5672 in Room 2007)

Break Size:

-Large Isolabitity of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 is not assumed necessary to allow successful injection of the RWT into the containment (this is only a 2 inch pipe). If needed, it is.

assumed this train would be operated and not isolated during the RWT injection phase. Also, CSS could be isolated locally by closing 2BS-2B in Room 2007 which would allow operation of HPSI B and LPSI B without further leakage into the room. Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm.

Spatial Effects: Propagatia Spatial Effects Comments:

Initiating Event: N n

Effected Location:

Room 2007 Flooding is assumed to affect train B ECCS in Room 2007 if not isolated. Another opportunity to recognize the need for isolation is assumed to occur during recirculation actuation. Failure to isolate during the second opportunity by closing 2CV-5648 or 2CV-5650 (may be flooded) is assumed to fail the recirculation phase of inventory control and heat removal. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure case (2 failures) is assumed to leadto loss of containment sump (common cause failure of ECCS recirculation).

Loss of Train:

TM-3 Train ED:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of only CSS train B.-Failure to isolate before recirculation (1 failure) is assumed to lead to failure of ECCS train B due to flooding in the room.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18.(uncxpected frequency of challenge, between test exposure, and I backup trains - CSS A in recirculation). The failure to isolate cases are "Low" consequence based on 2 backup trains (isolation and ECCS A or 2 isolations).

Consequence Category: MEDIUM El Consequence Rank IJ Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 24 of 40 FMECA - Consequence Information Report Calculaton No. A-PENG-CALC-O5. Rev. 00

,4-Sep-9 Page A15 of A3 Consequence ID: CSS-C-09A Consequence

Description:

Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2014 during an independent demand (line 2GCB-16 in Room 2014)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2014 Spatial Effects Comments: Flooding is assumed to affect train A ECCS in Room 2014 before isolation can occur, Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2007 (ECCS train B). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (Mvi) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ED:

CSS, HPSI. LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A due to flooding in the room before isolation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and lbackup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).

Consequence Category: ME*DIUrM 13 Consequence Rank

[]

Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 25 of 40 FMECA - Consequence Information Report Calculafion No. A-PENG-CALC-OiS. Rev. 00 14-Sep.9 Page A16 of A31 Consequence ID: CSS-C-09B Consequence

Description:

Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2007 during an independent demand (line 2GCB-17 in Room 2007)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase): Detection is based on Room 2007 flood alarm, auxiliary building sump high level alarm, and CSS low flow alarm if the break is large enough and upstream of flow element. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2007 Spatial Effects Comments: Flooding is assumed to affect train B ECCS in Room 2007 before isolation can occur. Failure to isolate is assumed to propagate into Rooms 2006 & 2011 through ventilation openings, but the RWT can not flood 2014 (ECCS train A). However, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B due to flooding in the room before isolation.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9. 18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on 1 backup train (isolation),

Consequence Category': hEEDUJM 0

Consequence Rank r13 Consequence Category: MEDIUM 0

Consequence Rank C

Enclosure to CNRO-2007-00028 Page 26 of 40 FMECA - Consequence Information Report Cak,,dadon No. A-PENG-C4LC-O i. Rm. 00 14-Sep-9 Page A]7 of A31 Consequence ID: CSS-C-10A Consequence

Description:

Degradation of Pump 2P35A discharge test return upstream of 2SI-5A in Room 2011 during an independent demand (line 2GCB-16 in Room 2011)

Break Size:

Large Isolabitity of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2011 Spatial Effects Comments: Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventory to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3.

System IWE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).

Consequence Category: MIEDIUM

["].

Consequence Rank 11 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 27 of 40 FMECA - Consequence Information Report 14-Sep-9 Calcula don No. A-PENG-CALC-01S, Rv. 00 Page A18 of A31 Consequence ED:. CSS-C-10B Consequence

Description:

Degradation of Pump 2P35B discharge test return upstream of 2SI-SB in Room 2011 during an independent demand (line 2GCBT17 in Room 2011)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occr during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N n

Effected Location:

Room 2011 Failure to isolate is assumed to propagate into Rooms 2007, 2010, & 2014 through ventilation openings even if they do isolate automatically on a SI signal. Also, failure to isolate can be assumed to result in loss of sufficient RWT inventry to fail containment sump recirculation. Detection is provided by auxiliary building sump high level alarm in the control room.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (MI) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train A). The failure to isolate case is a "Medium" consequence based on I backup train (isolation).

Consequence Category: MEDIUM F-1 Consequence Rank r]

Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 28 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-015,Rev. 00 14-Sep-9 Page A19 of A31 Consequence ID: CSS-C-lIA Consequence

Description:

Degradation of Pump 2P35A discharge downstream of heat exchanger 2E35A in Room 2055 during an independent demand (line 2GCB-16 in Room 2055)

Break Size:

Large Isolability of Break. Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2055 Spatial Effects Comments: There are no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). If unisolated, El 317 will fill up and.

propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS. HPSI, LPSI System Recovery: isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS train B). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on' containment isolation.

Consequence Category: MEDUJM

'Consequence Rank 11 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 29 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-O)3, Rev. 00 14-Sep-9 Page A20 of A31 Consequence ED: CSS-C-11B Consequence

Description:

Degradation of Pump 2P35B discharge downstream of heat exchanger 2E35B in Room 2055 during an independent demand (line 2GCB-17 in Room 2055)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2055 Spatial Effects Comments: There arc no impacts in Room 2055, but propagation is into Room 2040 where MCC 2B52 is located. Isolation failure is assumed to be affected by this MCC.

Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and the east stair well. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment stunp recirculation A). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.

Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains due to the assumed impact on MCC 2B52 before isolation, but containment cooling provides backup train.-

Loss of Train:

TM-3 Train El:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B and both trains of CSS as described above.

Consequence Comment: Consequence is '!Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and one backup train). The failure to isolate case is a "Medium" based on one backup train (isolation). No impact on containment isolation.

Consequence Category: MIEDIUM 13 Consequence Rank

[]

Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 30 of 40 FMECA - Consequence Information Report Cakulation No. A-PENG-CA W-0L1, Rev. 00 14-Sep-9 Page A21 of A31 Consequence ID: CSS-C-12A Consequence

Description:

Degradation of Pump 2P35A discharge upstream of 2CV-5612 in Room 2084 during an independent demand (line 2GCB-16 in Room 2084)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT-level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.

Propagation into Room 2040 where MCC 2B52 is located in the corridor. Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 21362 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS.

Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:.

TM-3 Train ED:

CSS A, HPSI A, LPSI A Train Recovery: Isolation success leads to loss of ECCS train A.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train). The failure to isolate case is a "Medium" based on I backup train (isolation). No impact on containment isolation.

Consequence Category: MEDIUM

[]

Consequence Rank 0

Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 31 of 40 FMECA - Consequence Information Report Calycodon No. A-PENG-CALC-01S. Rev. 00 14-Sep-9 Page A22 of A31 Consequence 11): CSS-C-12B Consequence

Description:

Degradation of Pump 2P35B discharge upstream of 2CV-5613 in Room 2084 during an independent demand (line 2GCB-17 in Room 2084)

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2084 Spatial Effects Comments:, In Room 2084, the potential exists for spray impacts on RPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.

Propagation is into Room 2040 where MCC 2B52 is located in the corridor.

Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-3 Train ID:

CSS B, HPSI B, LPSI B Train Recovery: Isolation success leads to loss of ECCS train B.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of

  • challenge, between test exposure, and 1 backup train). The failure to isolate case is "Medium" based on I backup train (isolation). No impact on containment isolation.

Consequence Category:, MEDIUM Consequence Rank 0]

Consequence Category: MEDIUM 0

Consequence Rank C

Enclosure to CNRO-2007-00028 Page 32 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-CAC-015. Rev. 00 Page A23 of A31 Consequence ID: CSS-C-13A Consequence

Description:

Degradation of Pump 2P35A discharge downstream of 2CV-5612 in Room 2084 during an independent demand (line 2HCB-20)

Break Size:

Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N On Effected Location:

Room 2084 In Room 2084, the potential exists for spray impacts on -PSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.

Propagation is into Room 2040 where MCC 2B52 is located in the corridor.

Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 and 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery; Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation. Isolation success also leads to loss of both CSS trains in recirculation due to assumed impact on MCC 2B62 before isolation (discharge MOV 2CV-5613 is assumed to open prior to impact on MCC).

Loss of Train:

TM-1 Train ID:

CSS A Train Recovery: Isolation success leads to loss of CSS train A, but containment cooling provides backup.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (uneixpcted frequency of challenge, all year exposure, and one backup train (isolation)) for failure to isolate case. The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5A provides containment isolation inside containment.

Consequence Category: MEDIUM III III 3

Consequence Rank 11 Consequence Category: MEDIUM 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 33 of 40 FMECA - Consequence Information Report Calculagion No. A-PENG-CALC-01, Rev. 00 14-SeP 9 Page A24 of A31 Consequence ID: CSS-C-13B Consequence

Description:

Degradation of Pump 2P35B discharge downstream of 2CV-5613 in Room 2084 during an independent demand (line 2HCB-21)

Break Size:

Large Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is-based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2084 Spatial Effects Comments: In Room 2084, the potential exists for spray impacts on HPSI and LPSI discharge valves. It is assumed there is sufficient separation between trains as with the CSS valves in this room. Propagation is into Room 2073 (EL 354) where MCC 2B62 is located, but flooding of the MCC is judged unlikely. From Room 2073 propagation continues easily to El 335 (Room 2040) through floor grating and the east stairway.

Propagation is into Room 2040 where MCC 2B52 is located in the corridor.

Isolation failure is assumed to affect this MCC. Room 2040 propagates to El 317 (Rooms 2006 & 2011) through floor drains and east stairway. MCC 2B52 contains breakers for normally closed CSS valves 2CV-5612-1 and 5649-1 (containment sump recirculation A). MCC 2B62 contains breakers for normally closed CSS valves 2CV-5613-2 an d 5650-1 (containment sump recirculation B). If unisolated, El 317 will fill up and propagate into the ECCS rooms (2007, 2010, & 2014) failing all ECCS. Detection is provided by auxiliary building sump high level and ECCS room flood alarms in the control room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: SM-3 System IPE ID:

CSS, HPSI, LPSI System Recovery: Isolation failure is assumed to fail all ECCS due to insufficient RWT inventory in the containment sump to support recirculation.

Loss of Train:

TM-I Train ID:

CSS B Train Recovery: Isolation success leads to loss of CSS train B, but containment cooling provides backup.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and, I backup train for failure to isolate). The successful isolation case is a "Low" consequence with two backup trains counting containment cooling. 2BS-5B provides containment isolation inside containment Consequence Category: MEDIUM 11 Consequence Rank I1 Consequence Category: MEDIUM C

Consequence Rank C

Enclosure to CNRO-2007-00028 Page 34 of 40 FMECA - Consequence Information Report Cal,-aIdon No A-PENIG-CALC-OIS. Rev. 00 14-Sep-9 Page A25 of A31 Consequence ID: CSS-C-14A Consequence

Description:

Degradation of Pump 2P35A discharge downstream of 2CV-5612 inside containment during an independent demand (line 2HCB-3 upstream of 2BS5-SA)

Break Size:

Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612. but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect except containment pressure may not reduced as fast as expected and train B is still available.

Spatial Effects: Containment Effected Location:

Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event Initiating Event: N Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System IPE ED:

N/A System Recovery: N/A Loss of Train:

N Train ID:

N/A Train Recovery: Loss of CSS train A occurs only if the train is isolated by the operators. The train is still capable of performing its containment heat removal function.

Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).

2CV-5612 and closed system outside provide containment isolation.

Consequence Category: LOW 01 Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 35 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-015, Rev. 00 14-Sep79 Page A26 of A31 Consequence ID: CSS-C-14B Consequence

Description:

Degradation of Pump 2P35B discharge downstream of 2CV-5613 inside containment during an independent demand (line 2HCB-4 upstream of 2BS-5B)

Break Size:

Large.

Isolability of Break. Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613, but this is not necessary to prevent additional impacts since the RWT is being pumped to the containment (the pipe break affects spray effectiveness, but not the heat removal fuction). Not easy to detect exceptcontainment pressure may not reduced as fast as expected and train A is still available.

Spatial Effects: Containment' Effected Location:

Containment Building Spatial Effects Comments: Equipment inside containment is qualified for this event.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System WE ID:

N/A System Recovery: N/A Loss of Train:

N Train ID:

N/A Train Recovery: Loss of CSS train B occurs only if the train is isolated by the operators. The train is still ca*able of performing its containment heat removal function.

Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).

2CV-5613 and closed system outside provide containment isolation.

Consequence Category: LOW 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 36 of 40 FMECA - Consequence Information Report 14-Sep-9 Calculation No. A-PENG-C4LC-OIS, Rev. 00 Page A27 of A31 Consequence ID: CSS-C-15A Consequence

Description:

Degradation of NAOH line to Train A (line 2GCB-70) during an independent demand.

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5630 may be required to prevent gravity draining through pump 2P35A from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2014 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event:. N n

Effected Location:

Room 2014 Since this is a small line (2 inch diameter), flooding of ECCS train A in Room 2014 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.

Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the ECCS room.

Initiating Event ED: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System IPE ID:

N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).

Loss of Train:

TM-3

' Train ED:

CSS A, HPSI A, LPSI A Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS. thus, allowing recovery of HPSI and LPSI.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and 1 backup train - ECCS B). Containment isolation is unaffected.

Consequence Category: MEDIUM 13]

Consequence Rank 1-1 Consequence Category: MEDIUM C

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 37 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CAL-015, Rev. 00 14-Sep-9 Page A28 of A31 Consequence IOD: CSS-C-15B Consequence

Description:

Degradation of NAOH line to Train B (line 2GCB-69) during an independent demand.

Break Size:

Large Isolability of Break: Yes ISO Comments: Tripping the pump and closing suction MOV 2CV-5631 may be required to prevent gravity draining through pump 2P35B from the RWT (break is assumed to occur during RWT injection phase). Detection is based on Room 2007 flood alarm and auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location: Room 2007 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding of ECCS train B in Room 2007 is assumed only if isolation fails. Also, flow diversion impacts are not assumed.

Failure to isolate is not assumed to propagate into Rooms 2006 & 2011 during injection phase due to break size. Detection is'provided by ECCS room flood and auxiliary building sump high level alarms in the control room. Loss of train B must be assumed during the recirculation phase due to isolation,'otherwise, the containment sump would be emptied into the ECCS room.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System IPE ID:

N/A System Recovery, Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).

Loss of Train: - TW-3 Train ED:

CSS B, HPSI B, LPSI B Train Recovery: Isolation of ECCS train during recirculation is required. No credit is allowed for local isolation of CSS, thus, allowing recovery of -PSI and LPSI.

Consequence Comment: Consequence is "Medium" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, between test exposure, and I backup train - ECCS A). Containment isolation is unaffected.

Consequence Category: MEDIUM 13 Consequence Rank I

.3 Consequence Category: MEDIUM 0

Conseriucoce Rank 0

Enclosure to CNRO-2007-00028 Page 38 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-01S. Rev. 00 14-Sep-9 Page A29 of A31 Consequence ID: CSS-C-16 Consequence

Description:

Degradation of RWT suction to SFPP and charging (line 2HCB-7) during an independent demand.

Break Size:

Large Isolability of Break: No ISO Comments: Unisolable.

Spatial Effects: Propagation Effected Location:

Outside Spatial Effects Comments: This piping is located both outside near the RWT and in Room 2040. Propagation from Room 2040 is down to El 317 (Rooms.2006 & 2011) through floor drains and east stairway. Detection is provided by auxiliary building sump high level alarm, but this is irrelevant since the break is unisolable. This line is judged too small (3 inch diameter) to divert enough of the RWT to cause flow diversion or loss of ECCS.

Initiating Event: N

. Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System IPE ID:

N/A System Recovery: Pipe size is assumed too small to cause flow diversion or loss of ECCS.

Loss of Train:

N Train ID:

N/A Train Recovery: N/A Consequence Comment: Consequence is '!Low" base on Table 2-2 of Ref 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains - CSS A & B and ECCS A & B).

Containment isolation is unaffected.

Consequence Category: LOW E)

Consequence Rank 03

Enclosure to CNRO-2007-00028 Page 39 of 40 FMAECA - Consequence Information Report Calculation No. A.PENG-CALC-0O5. Rev. 00 14-Sep-9 Page A30 of A3)

Consequence ID: CSS-C-17A Consequence

Description:

Degradation of service air connection to Train A (line 2HCB-93) during an independent demand.

Break Size:

Large Isolability of Break: Yes ISO Comments: Trip pump 2P35A or close MOV 2CV-5612 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagation Effected Location:

Room 2084 Spatial Effects Comments: Since this is a small line (2 inch diameter), flooding impact is not assumed. Also.

flow diversion impacts are not assumed. Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS A must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.

Initiating Event: N Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System IPE ID:

N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).

Loss of Train:

T Train ID:

CSS A Train Recovery: Isolation of CSS train during recirculation is required (2CV-5612). This allows HPSI A &

LPSI A success. Also, containment cooling system can replace CSS A.

Consequence Comment: Consequence is "Low" based on Table 2-2 of Ref. 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; -PSL LPSI, CSS B, and containment cooling). 2BS-SA provides containment isolation inside containment Consequence Category: LOW 1"3 Consequence Rank

[]

Consequence Category: LOW 0

Consequence Rank 0

Enclosure to CNRO-2007-00028 Page 40 of 40 FMECA - Consequence Information Report Calculation No. A-PENG-CALC-0i5, Rev. 00 14-Sep-9 Page A31 of A31 Consequence ID: CSS-C-17B Consequence

Description:

Degradation of service air connection to Train B (line 2HCB-94) during an independent demand.

Break Size:

Large Isolability of Break: Yes ISO Comments: Trip pump 2P35B or close MOV 2CV-5613 (break is assumed to occur during RWT injection phase). Detection is based on auxiliary building sump high level alarm. A low RWT level alarm will also occur, but it could be associated with the assumed LOCA condition.

Spatial Effects: Propagatio Spatial Effects Comments:

Initiating Event: N pn Effected Location:

Room 2084 Since this is a small line (2 inch diameter), flooding impact is not assumed. Also, flow diversion impacts are not assumed-Detection is provided by auxiliary building sump high level alarms in the control room. Loss of train CSS B must be assumed during the recirculation phase due to isolation, otherwise, the containment sump would be emptied into the auxiliary building.

Initiating Event ID: N/A Initiating Event Recovery: A medium LOCA (M) initiator is assumed to challenge this piping.

Loss of System: N System WIE ID:

N/A System Recovery: Loss of all ECCS during recirculation phase is possible if the containment sump was pumped to the auxiliary building. This is judged to be equivalent to 2 isolation failures (2 backup trains).

Loss of Train:

T Train ED:

CSS B Train Recovery: Isolation of CSS train during recirculation is required (2CV-5613). This allows HPSI B &

LPSI B success. Also, containment cooling system can replace CSS B.

Consequence Comment: Consequence is "Low" based on Table 2-2 of Ret 9.18 (unexpected frequency of challenge, all year exposure, and 2 backup trains; HPSI. LPSI, CSS A, and containment cooling). 2BS-5B provides containment isolation inside containment.

Consequence Category: LOW 0

Consequence Rank 11 Consequence Category:

LOW 0

Consequence Rank 0

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