ML091470570
| ML091470570 | |
| Person / Time | |
|---|---|
| Site: | Boiling Water Reactor Owners Group |
| Issue date: | 06/16/2009 |
| From: | Michelle Honcharik NRC/NRR/DPR/PSPB |
| To: | Coleman D BWR Owners Group, Energy Northwest |
| Honcharik M, NRR/DPR/PSPB, 415-1774 | |
| References | |
| NEDO-33349, Rev 1, TAC MD6697 | |
| Download: ML091470570 (21) | |
Text
June 16, 2009 Mr. Doug Coleman Chair, Boiling Water Reactor Owners' Group Energy Northwest Columbia Generating Station Mail Drop PE20 P.O. Box 968 Richland, WA 99352-0968
SUBJECT:
SUPPLEMENTAL REQUEST FOR ADDITIONAL INFORMATION RE: BOILING WATER REACTOR OWNERS= GROUP LICENSING TOPICAL REPORT NEDO-33349, REVISION 1, BWR APPLICATION TO REGULATORY GUIDE 1.97 REVISION 4 (TAC NO. MD6697)
Dear Mr. Coleman:
By letter dated August 31, 2007 (Agencywide Documents Access and Management System Accession No. ML072470741), the Boiling Water Reactor Owners' Group (BWROG) submitted for U.S. Nuclear Regulatory Commission (NRC) staff review licensing topical report NEDO-33349, Revision 1, BWR Application to Regulatory Guide 1.97 Revision 4. The NRC staff transmitted requests for additional information (RAI) by letters dated August 4 and 19, 2008 (ADAMS Accession Nos. ML081650030 and ML082210454, respectively). You responded to the RAIs by letter dated October 31, 2008 (ADAMS Package Accession No. ML083090576).
Upon review of the information provided, the NRC staff has determined that additional information is needed to complete the review. Enclosed are the NRC staff's supplemental RAI questions. On June 8, 2009, Mr. Mike Iannantuono, Project Manager, and I agreed that the NRC staff will receive your response by September 4, 2009. If you have any questions regarding the enclosed RAI questions, please contact me at 301-415-1774.
Sincerely,
/RA by R.Subbaratnam for/
Michelle C. Honcharik, Senior Project Manager Special Projects Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No. 691 cc: See next page
Enclosure:
Supplemental RAI
ML081650030 and ML082210454, respectively). You responded to the RAIs by letter dated October 31, 2008 (ADAMS Package Accession No. ML083090576). Upon review of the information provided, the NRC staff has determined that additional information is needed to complete the review. Enclosed are the NRC staff's supplemental RAI questions. On June 8, 2009, Mr. Mike Iannantuono, Project Manager, and I agreed that the NRC staff will receive your response by September 4, 2009. If you have any questions regarding the enclosed RAI questions, please contact me at 301-415-1774.
Sincerely,
/RA by R.Subbaratnam for/
Michelle C. Honcharik, Senior Project Manager Special Projects Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Project No. 691 cc: See next page
Enclosure:
Supplemental RAI DISTRIBUTION:
PUBLIC RidsNrrDpr PSPB Reading File RidsNrrDprPspb RidsNrrLADBaxley RidsAcrsAcnwMailCenter RidsNrrPMMHoncharik RidsOgcMailCenter RidsNrrDeEicb RidsNrrDssSrxb Kevin Williams, NSIR Kathryn Brock, NSIR Barry Marcus Steve LaVie, NSIR Tai Huang Aron Lewin RidsNrrDirsItsb ADAMS ACCESSION NO.: ML091470570
- No major changes from input. NRR-106 OFFICE PSPB/PM PSPB/LA EICB/BC NSIR/BC PSPB/BC PSPB/PM NAME MHoncharik (RSubbaratnam for)
DBaxley WKemper KWilliams*
SRosenberg MHoncharik (RSubbaratnam for)
DATE 06/16/09 6/8/09 5/26/09 5/27/09 6/16/09 6/16/09
BWR Owners= Group Project No. 691 Mr. Richard Libra Executive Vice Chair, BWR Owners= Group Exelon Generation Co, LLC 200 Exelon Way Mail Code KSA 2-N Kennett Square, PA 19348 Rick.libra@exeloncorp.com Mr. Richard Anderson BWROG, Executive Chair FPL Energy (DAEC)
Duane Arnold Energy Center 3277 DAEC Road Palo, IA 52324 richard_l_anderson@fpl.com Mr. James F. Klapproth GE-Hitachi Nuclear Energy M/C A50 3901 Castle Hayne Road Wilmington, NC 28401 james.klapproth@ge.com Mr. Joseph E. Conen, Vice Chair Regulatory Response Group BWR Owners= Group DTE Energy-Fermi 2 200 TAC 6400 N. Dixie Highway Newport, MI 48166 conenj@dteenergy.com Dennis Madison, Hatch Vice President Southern Nuclear Operating Co.
11028 Hatch Parkway North Baxley, GA 31515-2010 drmadiso@southernco.com Frederick Emerson BWROG, Project Manager Frederick.emerson@ge.com Mr. Ken A. McCall, Program Manager GE-Hitachi Nuclear Energy M/C F12 3901 Castle Hayne Road Wilmington, NC 28401 kenneth.mccall@ge.com Oscar Limpias Entergy Nuclear Northeast 1340 Echelon Parkway.
Jackson, MS 39213-8202 olimpia@entergy.com Joe Donahue Progress Energy Inc.
410 S. Wilmington St.
PEB 6A Raleigh, NC 27601-1849 joe.w.donahue@pgnmail.com Paul J. Davison Hope Creek Generating Station P.O. Box 236 Hancocks Bridge, NJ 08038 paul.davison@pseg.com Mr. Ted Schiffley Vice Chairman, BWROG Exelon Generation Co., LLC.
Cornerstone II at Cantera 4300 Winfield Road Warrenville, IL 60555 frederick.schiffley@exeloncorp.com Mr. Randy C. Bunt, Chair Regulatory Response Group Southern Nuclear Operating Company 40 Inverness Center Parkway/Bin B057 Birmingham, AL 35242 rcbunt@southernco.com 8/6/08
ENCLOSURE SUPPLEMENTAL REQUEST FOR ADDITIONAL INFORMATION BOILING WATER REACTOR OWNERS' GROUP LICENSING TOPICAL REPORT NEDO-33349 REVISION 1, BWR APPLICATION TO REGULATORY GUIDE 1.97 REVISION 4 Boiling Water Reactor Owners' Group (BWROG) licensing topical report (LTR) NEDO-33349, Revision 1, BWR Application to Regulatory Guide 1.97 Revision 4, submitted by letter dated August 31, 2007 (Agencywide Documents Access and Management System (ADAMS)
Accession Number ML072470741), proposes technical justification for the use of Regulatory Guide (RG) 1.97 Revision 4 by currently licensed BWRs. By letter dated October 31, 2008 (ADAMS Accession Number ML083090576), the BWROG provided responses to the U. S.
Nuclear Regulatory Commission (NRC) staffs request for additional information (RAI). To support the NRC staffs review of the LTR the NRC staff needs clarification of several issues.
- 1.
RG 1.97 Revision 3 recommends Drywell Pressure as a Type B Category 1 variable to monitor the Maintaining Reactor Coolant System Integrity function. NEDO-33349 uses the Pressure Control function instead of the RG 1.97 Revision 3 Maintaining Reactor Coolant System Integrity function and credits Reactor Pressure as a key variable for the Pressure Control function. However, based on the response to RAI 1-I&C-12 it is not clear if Drywell Pressure is or is not being credited, in NEDO-33349, as a key variable for the Pressure Control function.
The reason for this confusion is that the response indicates that Reactor Pressure is included in the Reactor Control Emergency Procedure Guidelines (EPGs) to support Reactor Pressure Vessel (RPV) integrity. The response also indicates that Drywell Pressure is an entry condition for the RPV Control EPG. Please clarify if NEDO-33349 credits Drywell Pressure as a key variable for providing information about the accomplishment of the Pressure Control function.
- 2.
RG 1.97 Revision 3 recommends Drywell Sump Level as a Type B Category 1 variable to monitor the Maintaining Reactor Coolant System Integrity function and Drywell Drain Sump Level as a Type C Category 1 variable to monitor the Reactor Coolant Pressure Boundary fission product barrier. NEDO-33349 uses the Pressure Control function instead of the RG 1.97 Revision 3 Maintaining Reactor Coolant System Integrity function and credits Reactor Pressure as a key variable for the Pressure Control function and Reactor Water Level, Reactor Pressure, Suppression Pool Temperature, and Suppression Pool Water Level as key variables for the Reactor Coolant Pressure Boundary fission product barrier.
Previous generic acceptance of the use of RG 1.97 Revision 3 alternate Category 3 instrumentation, in lieu of Category 1 Drywell Sump Level instrumentation, was based on (a) for small leaks the alternate instrumentation will not experience a harsh environment; (b) for large leaks, the sumps fill promptly and the sump drain lines isolate due to the increase in drywell pressure, negating the need for the measurement; (c) drywell pressure and temperature indication can be used to detect leakage into the drywell; and (d) the instrumentation neither automatically initiates nor alerts the operator to initiate operation of a safety system in a post-accident situation.
Please discuss the applicability of the above acceptance conditions in light of the fact that under NEDO-33349 neither Drywell Pressure nor Drywell Temperature is credited as a key variable for the Pressure Control function and Drywell Temperature does not meet the design and qualification criteria for a RG 1.97 Revision 4 Type B or Type C variable.
Please provide additional information on the NEDO-33349 claim that Drywell Sump Level is not relied on in safety analysis or EPGs for small or large leaks.
- 3.
NEDO-33349 credits Reactor Water Level as the key RG 1.97 Revision 4 Type C variable to provide information on the Fuel Cladding fission product barrier. The justification provided in NEDO-33349 is that Reactor Water Level is the parameter that provides the most direct indication of the fuel cladding fission product barrier integrity; the integrity of the fuel cladding barrier is maintained intact when the core remains adequately cooled by water in the reactor; and a breach of the fuel cladding barrier is assumed when adequate core cooling cannot be restored or has not been maintained.
Responses to RAI 1-I&C-13, RAI 3-NSIR-11, and RAI 3-NSIR-14 discuss the use of Reactor Water Level as the key variable to provide information on the Fuel Cladding fission product barrier.
The NRC staff questions Reactor Water Level as the key variable for the Fuel Cladding fission product barrier. Reactor Water Level is a precursor for fuel damage but is not the most direct variable to provide information on the potential for breach or the actual breach of the Fuel Cladding fission product barrier. The arguments in the RAI responses have not addressed the technical issues raised by the RAIs.
The result of a Fuel Cladding fission product barrier failure would be an increase in containment radiation. The NRC staff has previously suggested that existing RG 1.97 Revision 3 Type E Category 1 Containment Area Radiation instrumentation could be used as the key variable to provide information on the Fuel Cladding fission product barrier.
Please discuss what variables would be credited as key variables for the Fuel Cladding fission product barrier, since the NRC staff has not been convinced that Reactor Water Level can fulfill this purpose.
- 4.
NEDO-33349 recommends the use of additional key variables to provide information for several functions under RG 1.97 Revision 4. These variables were not recommended as key variables for these functions under RG 1.97 Revision 3. The use of these variables is discussed in Section 7, Summary of Regulatory Guide 1.97 Revision Changes.
However, not all of these variables are listed under their corresponding functions in Table A-1, Accident Monitoring Variable Comparison, of the draft markup of NEDO-33349. One example is NEDO-33349 credits Reactor Water Level as a Type C variable to provide information on the accomplishment of both the Fuel Cladding fission product barrier and the Reactor Coolant Pressure Boundary fission product barrier. This is discussed on Pages 7-7 and 7-8 of the draft markup of NEDO-33349. However, Reactor Water Level is not included on Page A-6 of Table A-1 for either Fuel Cladding or Reactor Coolant Pressure Boundary. Please either update Table A-1 to include all variables under each function (function for Type B, fission product barrier for Type C, system for Type D, or release or environmental condition for Type E) that provide information for that function, or provide a table that includes all variables, including their functions and type, which are being credited as RG 1.97 Revision 4 variables (See Question 15 below).
- 5.
RG 1.97 Revision 3 recommends Suppression Chamber Spray Flow as a Type D Category 2 variable to monitor the operation of Primary Containment Related Systems.
Although NEDO-33349 discusses the use of residual heat removal (RHR) System Flow and RHR Valve Position, as an alternate to Suppression Chamber Spray Flow, it is not clear if credit is being taken for Suppression Chamber Spray Flow and/or alternate instrumentation to provide status information for Containment System performance and/or RHR System performance. Please provide information that clarifies if Suppression Chamber Spray Flow is credited, in NEDO-33349, with providing status information for Containment System performance and/or RHR System performance.
- 6.
RG 1.97 Revision 3 recommends Drywell Spray Flow as a Type D Category 2 variable to monitor the operation of Primary Containment Related Systems. Although NEDO-33349 discusses the use of RHR System Flow and RHR Valve Position, as an alternate to Drywell Spray Flow, it is not clear if credit is being taken for Drywell Spray Flow and/or alternate instrumentation to provide status information for RHR Safety System performance. It is also not clear if the credit is being taken for alternate instrumentation to provide status information for Containment System performance. Please provide information that clarifies if Drywell Spray Flow, and/or alternate instrumentation, is credited, in NEDO-33349, with providing status information for Containment System performance and/or RHR System performance.
- 7.
RG 1.97 Revision 3 recommends that RHR System Heat Exchanger Outlet Temperature as a Type D Category 2 variable to monitor operation of RHR Systems. NEDO-33349 recommends that RHR System Heat Exchanger Outlet Temperature be classified as a RG 1.97 Revision 4 Type D variable to provide information on the status of Decay Heat Removal Safety System performance. However, it is not clear if RHR System Heat Exchanger Outlet Temperature is being proposed as part of the RHR System and/or as a separate Decay Heat Removal System. Please clarify which systems RHR System Heat Exchanger Outlet Temperature is being credited as providing information about. Please describe the difference between the RHR System and the Decay Heat Removal System.
- 8.
NEDO-33349 credits Other RPV Normally Closed Isolation Valve Position Inside Containment Require Opening for [loss-of-coolant accident] LOCA, Other RPV Normally Closed Isolation Valve Position Outside Containment Require Opening for Pipe Breaks Outside Containment, and Normally Closed [containment isolation valve] CIV Position Inside Containment Require Opening for LOCA, as Type D variables to provide information on the status of Applicable System performance. Please identify the Applicable System(s) for each valve group.
- 9.
For Type D isolation variables, Other RPV Normally Closed Isolation Valve Position on Valves that Do Not Require Opening for either LCOA or Pipe Breaks Outside Containment and Normally Closed CIV Position Inside or Outside Containment Do Not Require Opening for LOCA, the NEDO-33349 system is not Required for Safety System Performance Indication. Please provide more details of Not Required for Safety System Performance Indication system.
- 10.
RG 1.97 Revision 3 recommends that Main Steam Isolation Valves (MSIV) Leakage Control System Pressure be monitored by Type D Category 2 instrumentation to provide indication of pressure boundary maintenance for the Main Steam System. NEDO-33349 recommends that this instrumentation does not need to be considered a RG 1.97 Type D variable. In Table A-1, on Page A-9, the Comments column includes, NRC approved elimination of MSIV leakage control system. Please identify the NRC document that approved the elimination of the MSIV leakage control system.
- 11.
RG 1.97 Revision 3 recommends Drywell Purge and Standby Gas Treatment System Purge, Secondary Containment Purge, Secondary Containment, Auxiliary Building, Common Plant Vent or Multipurpose Vent, and All Other Identified Release Points, as locations for monitoring Noble Gases and Vent Flow Rate, as Type E Category 3 variables, to provide detection of significant releases and release assessment to monitor Airborne Radioactive Materials Release from Plant - Noble Gases and Vent Flow.
NEDO-33349 appears to recommend that these locations should be monitored by Type E instrumentation for Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate. Table A-1, on Page A-12, lists Noble Gases and Vent Flow Rate with the comment Plant-Specific list, includes all potential release points. The response to RAI 1-I&C-59 states, Table 5-1, Page 5-9 contains lists of release points for BWR/4 designs. However, Table 5-1, on Page 5-6, and Table 5-2, on Page 5-12, only includes Secondary Containment Release Point Flow as a Type E variable to monitor releases. Please identify the list of release points for Airborne Radioactive Materials Released from Plant - Noble Gases and Vent Flow Rate, credited in NEDO-33349, or clarify that the list is plant-specific and provide a general description of the locations that would be on plant-specific lists. Is Secondary Containment Release Point Flow a separate variable from the Noble Gases and Vent Flow Rate variables?
- 12.
RG 1.97 Revision 3 recommends Containment Effluent Radioactivity - Noble Gases (from Identified Release Points Including Standby Gas Treatment Vent) be monitored by Type C Category 3 instrumentation. NEDO-33349 recommends that this instrumentation does not need to be considered a RG 1.97 Revision 4 Type C variable. In Table A-1, on page A-7, there is an E in the IEEE-497 Consistent with RG 1.97 Rev 4 Type column, but in the BWR/4 Typical Type Column there is a C. Is this supposed to indicate that Containment Effluent Radioactivity - Noble Gases (from Identified Release Points Including Standby Gas Treatment Vent) is being credited, in NEDO-33349, as a RG 1.97 Revision 4 Type E variable? Please indicate any corrections that might be needed to Table A-1 or provide an explanation.
- 13.
RG 1.97 Revision 3 recommends that Type E Category 3 instrumentation be provided to monitor Estimation of Atmospheric Stability for release assessment for Meteorology assessment of releases. NEDO-33349 credits Ambient Air Temperature as a RG 1.97 Revision 4 Type E variable. In Table 5-1, on Page 5-6, and Table 5-2, on Page 5-12, Ambient Air Temperature is listed without a reference to Estimation of Atmospheric Stability. In Table A-1, on Page A-12, Estimation of Atmospheric Stability is listed without a reference to Ambient Air Temperature. Is it the intent of NEDO-33349 that Ambient Air Temperature replace Estimation of Atmospheric Stability or that both Ambient Air Temperature and Estimation of Atmospheric Stability be credited as RG 1.97 Revision 4 Type E variables? Whichever is the case should be clearly stated in NEDO-33349.
- 14.
RG 1.97 Revision 3 recommends that Type E Category 3 instrumentation be provided to monitor Containment Air Grab Sample for release assessment, verification, and analysis for Accident Sampling of the Containment Air. The responses to RAI 1-I&C-62 and RAI 3-NSIR-9 indicate that Containment Air sampling will be included as a RG 1.97 Revision 4 Type E variable, with reference to the NEDO-32991-A as to sampling capabilities. However, in Table A-1, on Page A-13, under the column titled, IEEE-497 Consistent with RG 1.97 Rev 4, Containment Air is listed as N/A, with the comment, Grab sample. See [post-accident sampling systems] PASS LTR. The NRC staff has been unable to find any discussion of the Containment Air Grab Sample Type E variable in NEDO-33349. Please clarify if NEDO-33349 credits Containment Air Grab Sample as a Type E variable and add the appropriate discussion in NEDO-33349.
Similar to Containment Air Grab Sample, Primary Coolant and Sump Grab Sample is listed in Table A-1, on Page A-13, under the column titled, IEEE-497 Consistent with RG 1.97 Rev 4, Primary Coolant and Sump is listed as N/A, with the comment, Grab sample. See PASS LTR. The NRC staff has been unable to find any discussion of the Primary Coolant and Sump Grab Sample Type E variable in NEDO-33349. Please clarify if NEDO-33349 credits Primary Coolant and Sump Grab Sample as a Type E variable and add the appropriate discussion in NEDO-33349.
- 15.
The purpose of Table A-1, as described on Page A-1, is to provide a comparison of the accident monitoring variables developed using the BWROG evaluation methodology to those in RG 1.97 Revision 2 and Revision 3 and a typical BWR/4 plant. However, Table A-1 does not include all RG 1.97 Revision 2 or Revision 3 variables or all NEDO-33349 variables. While Table A-1 is helpful in determining how the variables listed in the table would be applied under RG 1.97 Revision 4, it does not provide a complete picture for all variables that are being credited as RG 1.97 Revision 4 variables.
NEDO-33349 should include a table that includes all variables, including their functions and type, which are being credited as RG 1.97 Revision 4 variables.
- 16.
NEDO-33349 has recommended a significant number of changes from the list of variables in RG 1.97 Revision 3. The NRC staff has constructed the attached table to indicate the variables that NEDO-33349 recommends for each function under RG 1.97 Revision 4 and for each RG 1.97 Revision 3 variable that would no longer be monitored.
Please review the attached table to ensure that the NRC staff understands the NEDO-33349 position for each variable. The attached table should not be considered as an approval of any variable credited in NEDO-33349, but rather a summary of the recommendation in NEDO-33349. The NRC staff is aware that the responses to the above questions may have an impact on the attached table. Please provide corrections and/or comments to the attached table.
- 17.
RAI NSIR-11 Response/Supplemental RAI The NRC staff does not find the information provided by the BWROG in response to RAI NSIR-11 persuasive. As identified in Paragraph A of the RAI text, the NRC staff views the RPV level at any given time as only an indicator that precursor conditions to fuel damage exist; the level does not indicate that damage has occurred or its magnitude.
The NRC staff does not agree that the magnitude of core damage is irrelevant with respect to accident management strategies, as stated by the RAI response. The NRC staff considers the classification of emergency conditions to be a significant aspect of accident management and emergency preparedness. When plant design and the actions of plant operators are unsuccessful in preventing or mitigating the accident, reliance shifts to emergency preparedness. The NRC staff also notes that the effectiveness of public protective actions is enhanced when the actions are implemented prior to the start of a release (e.g., before such a release would be indicated by the Type E effluent monitors). The containment high range area monitors (CHARMs) provide a significant and critical input to the accident and emergency management decisions, especially given the retirement of the PASS at many facilities.
Although the NRC staff agrees that there can be significant uncertainties in detection of fuel damage by CHARMs, these uncertainties do not change the fact that, absent a common-mode failure of both CHARMs, a significantly elevated reading on these monitors can have only one meaning: core damage has occurred. The monitor reading under these circumstances will be proportional to the amount of core damage. Contrast this with the fact that the RPV level can only mean that conditions that could cause fuel damage are present. Once the RPV level is restored by ECCS, the RPV level reading provides no intelligence with regard to the occurrence or amount of core damage.
The NRC staff recognizes that a reactor coolant system (RCS) barrier failure has to occur before the fission products released into the RCS by core damage can be released to the drywell, as stated in the response. The NRC staff also recognizes that such a release could bypass the drywell. However, for the more probable accident sequences, the RCS barrier failure will precede the fuel clad barrier failure and the release will be to the drywell and will be indicated by the CHARMs.
The response that the CHARMs are challenged to provide on-scale indication during normal operation and may be unable to detect low levels of coolant activity, as stated in the response, is not a concern in as much as the CHARMs were installed to serve as post-accident monitors. The consequences of upsets in normal operations are administratively controlled by technical specifications on RCS specific activity, RCS leakage, and containment integrity, leak detection systems, normal range radiation monitors, etc., were evaluated by final safety analysis report analyses, and shown not to significantly affect public health and safety.
With regard to retention of fission products in the suppression pool as addressed in the RAI response, accident progression insights developed since Three Mile Island show that, although the blowdown of the RCS to the suppression pool will occur at the time of the RCS failure, the onset of release of gap fission products from the fuel will not occur before 2 minutes and will continue over several hours, with the release associated with core melt starting at about 30 minutes or later (See NUREG-1465). It is the blowdown of the RCS to the drywell that provides driving force for fission products to be driven into the suppression pool. Since this fuel damage occurs long after the blowdown occurs, significant fission product would be released to the drywell after the blowdown was complete and the pressure differential that would drive flow into the suppression pool had abated. Nonetheless, even if the suppression pool were to retain the aerosol fission products, the retention would not mitigate the substantial release of noble gas fission products from the fuel. Although the CHARM monitors could detect and measure iodine, the monitor indication is largely driven the noble gases released to the drywell. As the accident progresses, analyses indicate that drywell and suppression pool will behave as a single volume as the action of vacuum breakers and recirculation injection redistribute fission products. The NRC staff recognizes that there are uncertainties involved; nonetheless, elevated readings on the CHARMs can only be caused by fuel damage and the magnitude of those readings would be proportional to the magnitude of core damage. This cannot be said for the RPV level instrumentation as an indicator of actual fuel damage.
The NRC staff does not find the proposed reliance on RPV level as the sole indication of fuel clad barrier failure to be prudent or acceptable. The exchange between the RAI, the BWROG response to the RAI, and this supplementary RAI serve to highlight the need for diverse indications. This diversity is entirely in keeping with the defense-in-depth philosophy upon which plants were licensed. The NRC staff notes that another diverse means of assessing fuel damage, namely the post-accident sampling system, was previously retired at many plants, and is no longer available at those plants.
Please provide additional information which supports your position that designating the RPV level instrument as the sole Type C instrument for assessing the occurrence and magnitude of fuel damage, is technically appropriate and supportive of the defense-in-depth philosophy, or revise the LTR accordingly.
Attachment:
Table of NEDO-33349 Recommendations
ATTACHMENT NEDO-33349 Recommendations The following table includes the NEDO-33349 recommendations on the left side of the table and the Regulatory Guide (RG) 1.97 Revision 3 recommendations on the right side of the table. Where there are blanks on the left side of the table that variable was recommended as a RG 1.97 Revision 3 variable but is not recommended as a RG 1.97 Revision 4 variable for the same function. Where there are blanks on the right side of the table that variable was not recommended as a RG 1.97 Revision 3 variable for a particular function but is recommended as a RG 1.97 Revision 4 variable.
NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks A
Design Basis Event Reactor Water Level A
1 Design Basis Event Plant-Specific A
Design Basis Event Reactor Pressure A
1 Design Basis Event Plant-Specific A
Design Basis Event Drywell Pressure A
1 Design Basis Event Plant-Specific A
Design Basis Event Suppression Pool Temperature A
1 Design Basis Event Plant-Specific A
Design Basis Event Suppression Pool Water Level A
1 Design Basis Event Plant-Specific B
Reactivity Control Neutron Flux B
1 Reactivity Control Neutron Flux NEDO-31558 Also Type D B
3 Reactivity Control Control Rod Position Type D B
3 Reactivity Control RCS Soluble Boron Concentration Not a Rev 4 Variable B
Level Control Reactor Water Level B
1 Core Cooling Coolant Level in Reactor Vessel B
N/A Core Cooling BWR Core Temperature Not a Rev 4 Variable B
Pressure Control Reactor Pressure B
1 Maintaining Reactor Coolant System Integrity RCS Pressure B
Pressure Control Drywell Pressure B
1 Maintaining Reactor Coolant System Integrity Drywell Pressure NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks B
1 Maintaining Reactor Coolant System Integrity Drywell Sump Level Not a Rev 4 Variable B
Containment Control Drywell Pressure B
Containment Control Suppression Pool Temperature B
Containment Control Suppression Pool Water Level B
1 Maintaining Containment Integrity Primary Containment Pressure Drywell Pressure B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position Type D C
Fuel Cladding Reactor Water Level C
1 Fuel Cladding Radioactivity Concentration or Radiation Level in Circulating Primary Coolant Not a Rev 4 Variable C
3 Fuel Cladding Analysis of Primary Coolant Not a Rev 4 Variable C
N/A Fuel Cladding BWR Core Temperature Not a Rev 4 Variable C
Reactor Coolant Pressure Boundary Reactor Water Level C
Reactor Coolant Pressure Boundary Reactor Pressure C
1 Reactor Coolant Pressure Boundary RCS Pressure C
Reactor Coolant Pressure Boundary Drywell Pressure C
1 Reactor Coolant Pressure Boundary Drywell Pressure NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks C
Reactor Coolant Pressure Boundary Suppression Pool Temperature C
Reactor Coolant Pressure Boundary Suppression Pool Water Level C
1 Reactor Coolant Pressure Boundary Suppression Pool Water Level C
3 Reactor Coolant Pressure Boundary Primary Containment Area Radiation Type E C
1 Reactor Coolant Pressure Boundary Drywell Drain Sump Level Not a Rev 4 Variable C
Primary Containment Drywell Pressure C
Primary Containment Suppression Pool Temperature C
Primary Containment Suppression Pool Water Level C
1 Containment Primary Containment Pressure Drywell Pressure C
1 Containment RCS Pressure Not a Rev 4 Variable C
1 Containment Containment and Drywell Hydrogen 10 CFR 50.44 Not a Rev 4 Variable C
1 Containment Containment and Drywell Oxygen 10 CFR 50.44 Not a Rev 4 Variable C
3 Containment Containment Effluent Radioactivity - Noble Gases Type E C
2 Containment Effluent Radioactivity
- Noble Gases Type E NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
Containment System Drywell Pressure D
2 Primary Containment Related Systems Drywell Pressure D
Containment System Suppression Pool Temperature D
2 Primary Containment Related Systems Suppression Pool Temperature D
Containment System Suppression Pool Water Level D
2 Primary Containment Related Systems Suppression Pool Water Level D
Containment System Suppression Chamber Spray Flow D
2 Primary Containment Related Systems Suppression Chamber Spray Flow Alternate Instrument D
Containment System Drywell Temperature D
2 Primary Containment Related Systems Drywell Atmosphere Temperature D
Containment System Drywell Spray Flow D
2 Primary Containment Related Systems Drywell Spray Flow D
Reactor Protection System and Control Rod Drive System Neutron Flux B
1 Reactivity Control Neutron Flux NEDO-31558 Also Type B D
Reactor Protection System and Control Rod Drive System Control Rod Position B
3 Reactivity Control Control Rod Position No EQ or Seismic D
Safety Relief Valve System Safety Relief Valve Position D
2 Main Steam System Primary Safety Relief Valve Position NEDO-33160 No EQ or Seismic D
RCIC System RCIC System Flow D
2 Safety System RCIC Flow No EQ or Seismic D
RCIC System Condensate Storage Tank Water Level D
3 Condensate and Feedwater System Condensate Storage Tank Level No EQ or Seismic D
HPCI or HPCS System HPCI or HPCS System Flow D
2 Safety System HPCI Flow D
HPCI or HPCS System Condensate Storage Tank Water Level D
2 Condensate and Feedwater System Condensate Storage Tank Level No EQ or Seismic NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
2 Residual Heat Removal Systems RHR System Flow D
RHR System RHR System Valve Position D
RHR System Suppression Chamber Spray Flow D
2 Primary Containment Related Systems Suppression Chamber Spray Flow Alternate Instrument D
RHR System Drywell Spray Flow D
2 Primary Containment Related Systems Drywell Spray Flow Alternate Instrument D
Decay Heat Removal System RHR System Heat Exchanger Outlet Temperature D
2 Residual Heat Removal Systems RHR Heat Exchanger Outlet Temperature D
LPCS System LPCS System Flow D
2 Safety Systems LPCI System Flow D
LPCS System Core Spray Flow D
2 Safety System Core Spray System Flow D
Cooling Water System Cooling Water Temperature to ESF System Components D
2 Cooling Water System Cooling Water Temperature to ESF System Components Alternate Instrument D
RHR Service Water System RHR Service Water System Flow D
2 Cooling Water System Cooling Water Flow to ESF System Components Alternate Instrument D
Essential Service Water Flow System Essential Service Water System Flow Alternate Instrument D
RPV Isolation System MSIV Position D
RPV Isolation System Cleanup System Isolation Valve Position D
RPV Isolation System Shutdown Cooling System Isolation Valve Position NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
RPV Isolation System Other RPV Normally Open Isolation Valve Position Inside Containment D
RPV Isolation System Other RPV Normally Open Isolation Valve Position Outside Containment D
Applicable System Other RPV Normally Closed isolation Valve Position Inside Containment Require Opening for LOCA D
Applicable System Other RPV Normally Closed Isolation Valve Position Outside Containment Require Opening for Pipe Breaks Outside Containment D
Applicable System Normally Closed CIV Position Inside Containment Require Opening for LOCA B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
Not Required for Safety System Other RPV Normally Closed Isolation Valve Position Outside Containment Do Not Require Opening for either LOCA or Pipe Breaks Outside Containment No EQ or Seismic D
Not Required for Safety System Normally Closed CIV Position Inside or outside Containment Do Not Require Opening for LOCA B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position No EQ or Seismic D
Containment Isolation System Normally Open CIV Position Inside Containment B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position D
Containment Isolation System Normally Closed CIV Position Inside Containment Require Opening for LOCA B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position D
Containment Isolation System CIV Position Outside Containment Require Opening for LOCA B
1 Maintaining Containment Integrity Primary Containment Isolation Valve Position D
Secondary Containment System Secondary Isolation Damper Position D
Secondary Containment System Standby Gas Treatment Flow D
Control Room Environment System Control Room Isolation Damper Position NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
Control Room Environment System Emergency Ventilation Damper Position D
2 Ventilation Systems Emergency Ventilation Damper Position Alternate Instrument D
SLCS System Standby Liquid Control System Pumps Running No EQ or Seismic D
SLCS System Standby Liquid Control System Storage Tank Level D
2 Safety Systems SLCS Storage Tank Level No EQ or Seismic D
SLCS System Standby Liquid Control System Flow D
2 Safety Systems SLCS Flow No EQ or Seismic D
DC Power System DC Power Status D
2 Power Supplies Status of Standby Power D
AC Power System AC Power Status D
2 Power Supplies Status of Standby Power D
Equipment Area Cooling System Equipment Area Cooling System Cooling Water Temperature D
Essential Pneumatic Gas Supply System Essential Pneumatic Gas Supply Pressure D
3 Condensate and Feedwater System Main Feedwater Flow Not a Rev 4 Variable D
2 Main Steam System Main Steam Isolation Valves Leakage Control System Pressure Not a Rev 4 Variable D
2 Safety Systems Isolation Condenser System Shell-Side Water Level Not a Rev 4 Variable except BWR/2 & BWR/3 D
2 Safety Systems Isolation Condenser System Valve Position Not a Rev 4 Variable NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks D
3 Radwaste Systems High Radioactivity Liquid Tank Level Not a Rev 4 Variable E
Containment Radiation Containment Radiation E
1 Containment Radiation Primary Containment Area Radiation - High Range Includes Rev 3 Type C Containment Area Radiation E
Containment Radiation Reactor Building Area Radiation Level in Areas Requiring Access E
2 (Mark III) 3 (Mark 1 & 2)
Containment Radiation Reactor Building or Secondary Containment Area Radiation E
Containment Radiation Secondary Containment Release Point Radiation Level E
2 (Mark III) 3 (Mark 1 & 2)
Containment Radiation Reactor Building or Secondary Containment Area Radiation E
Area Radiation Radiation Exposure Rate E
3 Area Radiation Radiation Exposure Rate E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Drywell Purge and Standby Gas Treatment System Purge - Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Drywell Purge and Standby Gas Treatment System Purge E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Secondary Containment Purge - Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Secondary Containment Purge E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Secondary Containment
- Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Secondary Containment NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Auxiliary Building -
Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Auxiliary Building E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Common Plant Vent or Multipurpose Vent Discharge - Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate Common Plant Vent or Multipurpose Vent Discharge E
Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate All Other Identified Release Points - Noble Gases and Vent Flow Rate E
3 Airborne Radioactive Materials Released From Plant - Noble Gases and Vent Flow Rate All Other Identified Release Points E
Airborne Radioactive Materials Released From Plant - Noble Gases Secondary Containment Release Point Flow Rate E
Airborne Radioactive Materials Released From Plant - Noble Gases Containment Effluent Radioactivity - Noble Gases (from Identified Release Points Including Standby Gas Treatment System Vent)
C 3
Containment Containment Effluent Radioactivity - Noble Gases (from Identified Release Points Including Standby Gas Treatment System Vent)
E Airborne Radioactive Materials Released From Plant - Noble Gases Effluent Radioactivity -
Noble Gases C
2 Containment Containment Effluent Radioactivity - Noble Gases NEDO-33349 RG 1.97 Revision 3 Type Function Variable Type Category Function Variable Remarks E
Particulates and Halogens Particulates and Halogens All Identified Plant Release Points Sampling With Onsite Analysis Capability E
3 Airborne Radioactive Materials Released From Plant -
Particulates and Halogens Particulates and Halogens All Identified Plant Release Points Sampling With Onsite Analysis Capability E
Environs Radiation and Radioactivity Airborne Radiohalogens and Particulates E
3 Environs Radiation and Radioactivity Airborne Radiohalogens and Particulates E
Environs Radiation and Radioactivity Plant Environs Radiation E
3 Environs Radiation and Radioactivity Plant and Environs Radiation E
Environs Radiation and Radioactivity Plant and Environs Radioactivity E
3 Environs Radiation and Radioactivity Plant and Environs Radioactivity E
Environmental Conditions Wind Speed E
3 Meteorology Wind Speed E
Environmental Conditions Wind Direction E
3 Meteorology Wind Direction E
Environmental Conditions Ambient Air Temperature E
3 Meteorology Estimation of Atmospheric Stability Not a Rev 4 Variable E
Grab Sample Primary Containment Sump Grab Sample E
3 Accident Sampling Capability Primary Coolant and Sump Grab Sample E
Grab Sample Primary Containment Sump Grab Sample E
3 Accident Sampling Capability Primary Coolant and Sump Grab Sample E
Offgas System Radiation Offgas System Release Point Radiation E
Control Room Radiation Control Room Area Radiation Monitors