ML100910313: Difference between revisions

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| number = ML100910313
| number = ML100910313
| issue date = 05/31/2011
| issue date = 05/31/2011
| title = Staff'S Responses to Public Comments
| title = Staffs Responses to Public Comments
| author name = Helton D
| author name = Helton D
| author affiliation = NRC/RES/DRA
| author affiliation = NRC/RES/DRA
Line 18: Line 18:


=Text=
=Text=
{{#Wiki_filter:Response to Public Comments on Draft Regulatory Guide (DG) -1227 An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications" Proposed Revision 2 of RG 1.174 A notice that Draft Regulatory Guide, DG-1227 (Proposed Revision 1 of RG 1.177) was available for public comment was published in the Federal Register on September 3, 2009 on page 74 FR 45655. The Public Comment period ended November 3, 2009.
{{#Wiki_filter:1 Response to Public Comments on Draft Regulatory Guide (DG) -1227 An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications" Proposed Revision 2 of RG 1.174 A notice that Draft Regulatory Guide, DG-1227 (Proposed Revision 1 of RG 1.177) was available for public comment was published in the Federal Register on September 3, 2009 on page 74 FR 45655. The Public Comment period ended November 3, 2009.
Comments were received from the organizations listed below. The NRC has combined the comments and NRC staff disposition in the following table.
Comments were received from the organizations listed below. The NRC has combined the comments and NRC staff disposition in the following table.
#    Section /     Comment                                         Comment                                 NRC Response Reference    Source
Section /
: 1. General       NEI       A key companion document, RG 1.200, An Approach for determining the          The staff does not agree with the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-         commenter. Regulatory Guide Informed Activities, is listed in the references without a revision number; 1.177 references the revision of this should be corrected to specifically reference Revision 2. Referencing   RG 1.200 appropriate for the RG 1.200 without a revision number is not conducive to maintaining           application in question (i.e., the regulatory stability, as issuance of future revisions of RG 1.200 could       current revision unless a grace appreciably alter the implications of portions of RG 1.177 without any prior period is in effect).
Reference Comment Source Comment NRC Response
NRC or public review. The lack of a specific revision number in the reference could also lead to ambiguity in the guidance during the implementation period for any future revisions to RG 1.200, as during this time, it would not be clear which revision is intended in the reference.
: 1.
: 2. General       NEI,       Suggest changing allowed outage time to completion time and               The requested changes have PWROG      surveillance test interval to surveillance frequency throughout the      been made throughout the document to achieve consistency with NUREGs 1430-1434 as noted in the         document.
General NEI A key companion document, RG 1.200, An Approach for determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities, is listed in the references without a revision number; this should be corrected to specifically reference Revision 2. Referencing RG 1.200 without a revision number is not conducive to maintaining regulatory stability, as issuance of future revisions of RG 1.200 could appreciably alter the implications of portions of RG 1.177 without any prior NRC or public review. The lack of a specific revision number in the reference could also lead to ambiguity in the guidance during the implementation period for any future revisions to RG 1.200, as during this time, it would not be clear which revision is intended in the reference.
footnote on Page 2.
The staff does not agree with the commenter. Regulatory Guide 1.177 references the revision of RG 1.200 appropriate for the application in question (i.e., the current revision unless a grace period is in effect).
: 3. Page 4,       NEI       While the guide at hand focuses on changes to AOTs and STIs, it is           The requested change has been Purpose of              understood that other type changes to the Technical Specifications can also   made.
: 2.
this                    utilize the guidance; this should be better emphasized in this section. It is Regulatory              recommended that the second sentence of this paragraph, which deals with Guide, Last              other types of TS changes, be moved to the end of the section as a stand-Paragraph                alone paragraph.
General
1
: NEI, PWROG Suggest changing allowed outage time to completion time and surveillance test interval to surveillance frequency throughout the document to achieve consistency with NUREGs 1430-1434 as noted in the footnote on Page 2.
The requested changes have been made throughout the document.
: 3.
Page 4, Purpose of this Regulatory Guide, Last Paragraph NEI While the guide at hand focuses on changes to AOTs and STIs, it is understood that other type changes to the Technical Specifications can also utilize the guidance; this should be better emphasized in this section. It is recommended that the second sentence of this paragraph, which deals with other types of TS changes, be moved to the end of the section as a stand-alone paragraph.
The requested change has been made.


#  Section /   Comment                                   Comment                                     NRC Response Reference    Source
2 Section /
: 4. Page 4,     NEI     The last sentence in this paragraph, which discusses the possibility of       The staff does not agree with the Purpose of          additional or revised guidance for plants licensed under 10 CFR 52, should     commenters concern. No change this                be removed. This issue is being addressed in separate venues, and a           has been made.
Reference Comment Source Comment NRC Response
Regulatory          Commission-level decision may be forthcoming. The industry suggests that Guide, Last        such statements not be incorporated into regulatory guides until the Paragraph            decisionmaking process is complete.
: 4.
: 5. Page 4,     NEI     The industry appreciates that the RG has been revised to explicitly address   No change requested.
Page 4, Purpose of this Regulatory Guide, Last Paragraph NEI The last sentence in this paragraph, which discusses the possibility of additional or revised guidance for plants licensed under 10 CFR 52, should be removed. This issue is being addressed in separate venues, and a Commission-level decision may be forthcoming. The industry suggests that such statements not be incorporated into regulatory guides until the decisionmaking process is complete.
Scope of            both permanent and one-time changes.
The staff does not agree with the commenters concern. No change has been made.
Regulatory Guide, Last Paragraph
: 5.
: 6. Page 4,     Exelon In this section, the word "permanent" has been deleted from the phrase,       The parenthetical around AOT Scope of            "proposed permanent TS changes" in the first sentence and a revised last       was removed. The staff believes Regulatory          sentence now states: "... This regulatory guide provides guidance for both     that the existing wording already Guide, Last        permanent and one time only (AOT)changes to TS." In the past, this RG has     clarifies that exigent TS changes Paragraph            been specifically applicable ONLY to proposed permanent Technical             are included, while NOEDs are Specifications (TS) changes. One-time TS changes (e.g., Allowed               not.
Page 4, Scope of Regulatory Guide, Last Paragraph NEI The industry appreciates that the RG has been revised to explicitly address both permanent and one-time changes.
Outage Time (AOT) extensions, Notices of Enforcement Discretion (NOEDs), exigent TS changes), were not formally subject to the guidance of this RG, and expanding the scope provides useful guidance for evaluation of such non-permanent changes. However, in expanding the scope of applicability, does the inclusion of the parenthetical "(AOT)" in the last sentence limit one-time only changes to just AOT changes? Exelon requests clarification whether this draft RG is specifically not applicable to NOEDs or exigent TS changes.
No change requested.
2
: 6.
Page 4, Scope of Regulatory Guide, Last Paragraph Exelon In this section, the word "permanent" has been deleted from the phrase, "proposed permanent TS changes" in the first sentence and a revised last sentence now states: "... This regulatory guide provides guidance for both permanent and one time only (AOT)changes to TS." In the past, this RG has been specifically applicable ONLY to proposed permanent Technical Specifications (TS) changes. One-time TS changes (e.g., Allowed Outage Time (AOT) extensions, Notices of Enforcement Discretion (NOEDs), exigent TS changes), were not formally subject to the guidance of this RG, and expanding the scope provides useful guidance for evaluation of such non-permanent changes. However, in expanding the scope of applicability, does the inclusion of the parenthetical "(AOT)" in the last sentence limit one-time only changes to just AOT changes? Exelon requests clarification whether this draft RG is specifically not applicable to NOEDs or exigent TS changes.
The parenthetical around AOT was removed. The staff believes that the existing wording already clarifies that exigent TS changes are included, while NOEDs are not.


#  Section /   Comment                                     Comment                                     NRC Response Reference    Source
3 Section /
: 7. Page 4,     Exelon DG-1 227 does not refer to either RG 1.200 or NUREG-1 855. Both of those         Regulatory Guide 1.200 is in fact "Relationshi        documents establish expectations for PRA scope and technical acceptability       referenced in the DG. To augment p to Other          for risk-informed applications in a broad context. Exelon considers it           the existing reference, a Guidance            important for an RG for particular types of applications such as DG-1 227 to     paragraph has been added in the Documents"          provide additional guidance regarding how the other relevant guidance           Relationship to Other Guidance documents are to be applied.                                                     Documents section. A reference to NUREG-1855 has also been added. Also, the pending revision to RG 1.174 addresses the nexus between application-specific RGs (e.g., 1.177) and the guidance provided by RG 1.200 and NUREG-1855.
Reference Comment Source Comment NRC Response
: 8. Page 5,     NEI     There appears to be a philosophical difference in approach between DG-           We do not agree that the two DGs Risk-              1227 and DG-1226 (RG 1.174) when it comes to treatment of the traditional       are inconsistent in this respect. In Informed            engineering aspects of risk-informed decisionmaking. RG 1.174 states that       fact, the very sentence quoted Philosophy,          PRA can provide insights into whether the extent of defense-in-depth is         from DG-1227 also appears in Third              appropriate to ensure protection of public health and safety. However, to       DG-1226. No change has been Paragraph            address the unknown and unforeseen failure mechanisms or phenomena,             made.
: 7.
traditional defense-in-depth considerations should be used or maintained.
Page 4, "Relationshi p to Other Guidance Documents" Exelon DG-1 227 does not refer to either RG 1.200 or NUREG-1 855. Both of those documents establish expectations for PRA scope and technical acceptability for risk-informed applications in a broad context. Exelon considers it important for an RG for particular types of applications such as DG-1 227 to provide additional guidance regarding how the other relevant guidance documents are to be applied.
Regulatory Guide 1.200 is in fact referenced in the DG. To augment the existing reference, a paragraph has been added in the Relationship to Other Guidance Documents section. A reference to NUREG-1855 has also been added. Also, the pending revision to RG 1.174 addresses the nexus between application-specific RGs (e.g., 1.177) and the guidance provided by RG 1.200 and NUREG-1855.
: 8.
Page 5, Risk-Informed Philosophy, Third Paragraph NEI There appears to be a philosophical difference in approach between DG-1227 and DG-1226 (RG 1.174) when it comes to treatment of the traditional engineering aspects of risk-informed decisionmaking. RG 1.174 states that PRA can provide insights into whether the extent of defense-in-depth is appropriate to ensure protection of public health and safety. However, to address the unknown and unforeseen failure mechanisms or phenomena, traditional defense-in-depth considerations should be used or maintained.
DG-1227, on the other hand, states that risk analysis techniques can be, and are encouraged to be, used to help ensure and show that these
DG-1227, on the other hand, states that risk analysis techniques can be, and are encouraged to be, used to help ensure and show that these
[traditional engineering] principles are met. This seems inconsistent; further, Section 2.2.1 of DG-1227 appears to actually use the PRA to provide insights, not to show that the principles are met, which is more consistent with the RG 1.174 approach.
[traditional engineering] principles are met. This seems inconsistent; further, Section 2.2.1 of DG-1227 appears to actually use the PRA to provide insights, not to show that the principles are met, which is more consistent with the RG 1.174 approach.
: 9. Page 5,     NEI     While this section discusses the five principles, there is no specific reference A pointer to Figure 1 has been Risk-              to Figure 1, which depicts these principles, and the term Integrated           added. Integrated decisionmaking Informed            decisionmaking is never used. It is recommended Figure 1 be specifically       is already mentioned in the Philosophy          referenced, and that Integrated Decisionmaking as portrayed in Figure 1       second paragraph of this section.
We do not agree that the two DGs are inconsistent in this respect. In fact, the very sentence quoted from DG-1227 also appears in DG-1226. No change has been made.
also be mentioned.
: 9.
: 10. Page 5,     NEI     For items 2 and 3 change Regulatory Position 2.2 to Regulatory Position       The requested change was made.
Page 5, Risk-Informed Philosophy NEI While this section discusses the five principles, there is no specific reference to Figure 1, which depicts these principles, and the term Integrated decisionmaking is never used. It is recommended Figure 1 be specifically referenced, and that Integrated Decisionmaking as portrayed in Figure 1 also be mentioned.
Risk-              2.2.1 and Regulatory Position 2.2.2, respectively.
A pointer to Figure 1 has been added. Integrated decisionmaking is already mentioned in the second paragraph of this section.
Informed Philosophy, Items 2 and 3 3
: 10.
Page 5, Risk-Informed Philosophy, Items 2 and 3 NEI For items 2 and 3 change Regulatory Position 2.2 to Regulatory Position 2.2.1 and Regulatory Position 2.2.2, respectively.
The requested change was made.


#  Section /   Comment                                     Comment                                   NRC Response Reference  Source
4 Section /
: 11. Page 5,     PWROG   Discussion under Risk-Informed Philosophy, item 3: There is slightly           The requested change was made.
Reference Comment Source Comment NRC Response
Risk-              inconsistent with other sections by leaving out the words of this regulatory Informed            guide after Regulatory Position 2.2. Revise to be consistent.
: 11.
Philosophy, Item 3
Page 5, Risk-Informed Philosophy, Item 3 PWROG Discussion under Risk-Informed Philosophy, item 3: There is slightly inconsistent with other sections by leaving out the words of this regulatory guide after Regulatory Position 2.2. Revise to be consistent.
: 12. Page 6,     NEI     The implied stipulation for the licensee to directly describe how the proposed The sentence is unchanged from Element 1          TS change meets the objectives of the PRA Policy Statement would be           the current active version. The more clear if a reference were made to the guidance under Element 1 of         subsequent sentence states Section C, Regulatory Position. It is recommended the second to last         "Regulatory Position 1 describes sentence be revised to read The licensee should describe the proposed         element 1 in more detail." This change and how it meets the objectives of the Commissions PRA Policy         sentence provides the necessary Statement, including enhanced decisionmaking, more efficient use of           reference to details in the resources, and reduction of unnecessary burden as provided below in           referenced sections. A similar Sections 1.1.1, 1.1.2, and 1.1.3.                                             sentence is used in each of the subsequent elements 2-4, so making this element unique and referring to specific subsections of the regulatory position would introduce inconsistency.
The requested change was made.
: 13. Page 8,     NEI     The implied need for the applicant to directly evaluate compliance with the   This does not represent a change Section 2,          NRC Safety Goal Policy Statement rather than just with the acceptance         from the currently published First              guidelines of the regulatory guide seems an unnecessary burden for the         version of the RG. No change has Paragraph          licensee. The first sentence should be revised to read The licensee should   been made to the DG.
: 12.
examine the proposed TS change to verify that it meets existing applicable rules and regulations as expressed through the acceptance guidelines given in this regulatory guide.
Page 6, Element 1 NEI The implied stipulation for the licensee to directly describe how the proposed TS change meets the objectives of the PRA Policy Statement would be more clear if a reference were made to the guidance under Element 1 of Section C, Regulatory Position. It is recommended the second to last sentence be revised to read The licensee should describe the proposed change and how it meets the objectives of the Commissions PRA Policy Statement, including enhanced decisionmaking, more efficient use of resources, and reduction of unnecessary burden as provided below in Sections 1.1.1, 1.1.2, and 1.1.3.
: 14. Page 9,     NEI     The meaning of STS should be defined.                                       The acronym STS (Standard Element 2,                                                                                        Technical Specifications) is Last                                                                                              already defined on page 1.
The sentence is unchanged from the current active version. The subsequent sentence states "Regulatory Position 1 describes element 1 in more detail." This sentence provides the necessary reference to details in the referenced sections. A similar sentence is used in each of the subsequent elements 2-4, so making this element unique and referring to specific subsections of the regulatory position would introduce inconsistency.
Paragraph
: 13.
: 15. Page 10,   NEI     The fourth bullet should be modified unless it is deemed credible for         No change has been made.
Page 8, Section 2, First Paragraph NEI The implied need for the applicant to directly evaluate compliance with the NRC Safety Goal Policy Statement rather than just with the acceptance guidelines of the regulatory guide seems an unnecessary burden for the licensee. The first sentence should be revised to read The licensee should examine the proposed TS change to verify that it meets existing applicable rules and regulations as expressed through the acceptance guidelines given in this regulatory guide.
Section            changes to AOTs to introduce a new CCF mode, as opposed to changing           Technical specification changes 2.2.1,              the magnitude of CCF rates.                                                   could introduce new CCF Fourth                                                                                            mechanisms, since AOT changes Bullet                                                                                            are not the only changes covered by the Regulatory Guide.
This does not represent a change from the currently published version of the RG. No change has been made to the DG.
4
: 14.
Page 9, Element 2, Last Paragraph NEI The meaning of STS should be defined.
The acronym STS (Standard Technical Specifications) is already defined on page 1.
: 15.
Page 10, Section 2.2.1, Fourth Bullet NEI The fourth bullet should be modified unless it is deemed credible for changes to AOTs to introduce a new CCF mode, as opposed to changing the magnitude of CCF rates.
No change has been made.
Technical specification changes could introduce new CCF mechanisms, since AOT changes are not the only changes covered by the Regulatory Guide.  


#  Section /     Comment                                     Comment                                     NRC Response Reference      Source
5 Section /
: 16. Page 12,       NEI     To achieve better consistency with established (a)(4) guidance, the industry     The requested change has been Section 2.3,          suggests changing the first sentence of this section such that evaluated       made.
Reference Comment Source Comment NRC Response
Tier 3                before performing any maintenance activity is replaced with assessed and Heading                managed.
: 16.
: 17. Page 12,       NEI     Add and demonstration that a licensee meets the (a)(4) requirements is         No change has been made. The Section 2.3,          sufficient for Tier 3 assessments to the end of the first sentence of the first staff disagrees with the notion that Tier 3                paragraph.                                                                      the (a)(4) program alone always Heading                                                                                                satisfies Tier 3.
Page 12, Section 2.3, Tier 3 Heading NEI To achieve better consistency with established (a)(4) guidance, the industry suggests changing the first sentence of this section such that evaluated before performing any maintenance activity is replaced with assessed and managed.
: 18. Page 12,       Exelon "Contemporaneous Configuration Control," refers to Regulatory Position 2.3,     No change has been made. The
The requested change has been made.
    'Tier 3," 1 st        Tier 3, and with the revisions to Regulatory Position 2.3, these discussions     intent of the minor changes to the paragraph,            imply that the licensee program for compliance with 10 CFR 50.65(a)(4)           Tier 3 program discussion is to and Page              should provide an adequate approach to meeting Tier 3. The section of DG-       identify that the (a)(4) risk 20, "Key              1227 that originally specified inclusion of Configuration Risk Management       assessment is adequate to satisfy Component              Program (CRMP) in the Administrative Section of the TS has been removed.         that portion of Tier 3. Other 1,"Item #3            However, the discussion describing when to invoke the CRMP is still linked       existing items in the Regulatory Section                to TS AOTs, whereas 10 CFR 50.65(a)(4) does not link the performance of         Guide (such as consideration of 2.3.7,                any aspect of risk assessment to TS. Section 2.4 requires implementation of     external events risk, procedural a "risk-informed plant configuration control program" as a prerequisite for     controls, use for risk-informed TS AOT changes. In this regard:                                                     AOTs, etc.) are beyond the (a)(4)
: 17.
* Exelon requests clarification whether a licensee program which is in     requirements and are retained.
Page 12, Section 2.3, Tier 3 Heading NEI Add and demonstration that a licensee meets the (a)(4) requirements is sufficient for Tier 3 assessments to the end of the first sentence of the first paragraph.
compliance with 10 CFR 50.65(a)(4) meets the total intent of the "risk-informed plant configuration control program" prescribed in Section 2.4.
No change has been made. The staff disagrees with the notion that the (a)(4) program alone always satisfies Tier 3.
* Exelon requests clarification whether licensee programs for compliance with 10 CFR 50.65(a)(4) are adequate "as-is" for supporting TS changes pursuant to DG-1227. Are there additional requirements vis-a-vis Structures, Systems, or Components (SSCs) with TS AOTs?
: 18.
* Exelon recommends that if additional requirements are intended, then DG-1227 should be clear with respect to the scope of those SSCs. In other words, do those additional requirements apply to all TS SSCs with AOTs, or just the SSCs with AOTs that have been changed pursuant to DG-1 227?
Page 12,  
5
'Tier 3," 1 st paragraph, and Page 20, "Key Component 1,"Item #3 Section 2.3.7, Exelon "Contemporaneous Configuration Control," refers to Regulatory Position 2.3, Tier 3, and with the revisions to Regulatory Position 2.3, these discussions imply that the licensee program for compliance with 10 CFR 50.65(a)(4) should provide an adequate approach to meeting Tier 3. The section of DG-1227 that originally specified inclusion of Configuration Risk Management Program (CRMP) in the Administrative Section of the TS has been removed.
However, the discussion describing when to invoke the CRMP is still linked to TS AOTs, whereas 10 CFR 50.65(a)(4) does not link the performance of any aspect of risk assessment to TS. Section 2.4 requires implementation of a "risk-informed plant configuration control program" as a prerequisite for AOT changes. In this regard:
Exelon requests clarification whether a licensee program which is in compliance with 10 CFR 50.65(a)(4) meets the total intent of the "risk-informed plant configuration control program" prescribed in Section 2.4.
Exelon requests clarification whether licensee programs for compliance with 10 CFR 50.65(a)(4) are adequate "as-is" for supporting TS changes pursuant to DG-1227. Are there additional requirements vis-a-vis Structures, Systems, or Components (SSCs) with TS AOTs?
Exelon recommends that if additional requirements are intended, then DG-1227 should be clear with respect to the scope of those SSCs. In other words, do those additional requirements apply to all TS SSCs with AOTs, or just the SSCs with AOTs that have been changed pursuant to DG-1 227?
No change has been made. The intent of the minor changes to the Tier 3 program discussion is to identify that the (a)(4) risk assessment is adequate to satisfy that portion of Tier 3. Other existing items in the Regulatory Guide (such as consideration of external events risk, procedural controls, use for risk-informed TS AOTs, etc.) are beyond the (a)(4) requirements and are retained.


#  Section /   Comment                                     Comment                                       NRC Response Reference    Source
6 Section /
: 19. Page 12,     NEI     The last two paragraphs under the Tier 3 heading do not appear to be             Several changes were made to Section 2.3,        relevant to Tier 3 exclusively. As such, the information should be relocated     address this comment. The two Tier 3              to the appropriate sections on Tiers 1, 2, or 3; alternatively, a separate       paragraphs in question were Heading              heading could provide additional clarity. Additionally, the discussion should     moved to the end of the Section be revised to specify applicability of Regulatory Position 2.3.1 to any tiers. It 2.3 introduction, the requested is suggested that Regulatory Position 2.3.1 applies only to Tier 1.               change to the first sentence under Tier 3 was made, and a new final sentence was added to the first paragraph under Section 2.3.1.
Reference Comment Source Comment NRC Response
: 20. Page 12,     NEI     In the second sentence, in general should be changed to specifically.         The requested change was made.
: 19.
Section 2.3,                                                                                          Note that the paragraph in Tier 3                                                                                                question was moved up in Heading,                                                                                              response to the previous Second                                                                                                comment.
Page 12, Section 2.3, Tier 3 Heading NEI The last two paragraphs under the Tier 3 heading do not appear to be relevant to Tier 3 exclusively. As such, the information should be relocated to the appropriate sections on Tiers 1, 2, or 3; alternatively, a separate heading could provide additional clarity. Additionally, the discussion should be revised to specify applicability of Regulatory Position 2.3.1 to any tiers. It is suggested that Regulatory Position 2.3.1 applies only to Tier 1.
Paragraph
Several changes were made to address this comment. The two paragraphs in question were moved to the end of the Section 2.3 introduction, the requested change to the first sentence under Tier 3 was made, and a new final sentence was added to the first paragraph under Section 2.3.1.
: 21. Page 12,     NEI,   In the heading for Section 2.3.1, the word acceptability should be changed     The requested change has been Section      PWROG,  to adequacy to achieve consistency with other NRC documents, such as           made.
: 20.
2.3.1        Exelon  RG 1.200. This terminology should be similarly aligned throughout the document.
Page 12, Section 2.3, Tier 3
: 22. 2.3.1       PWROG   C. Regulatory Position: Note that no revision number to RG 1.200 is               No change has been made. The identified in the draft document. Add a one-sentence statement or footnote       applicable revision of RG 1.200 is regarding the process by which the appropriate revision can be identified.       the same revision that is germane to the application in question (i.e.,
: Heading, Second Paragraph NEI In the second sentence, in general should be changed to specifically.
The requested change was made.
Note that the paragraph in question was moved up in response to the previous comment.
: 21.
Page 12, Section 2.3.1
: NEI, PWROG, Exelon In the heading for Section 2.3.1, the word acceptability should be changed to adequacy to achieve consistency with other NRC documents, such as RG 1.200. This terminology should be similarly aligned throughout the document.
The requested change has been made.
: 22.
2.3.1 PWROG C. Regulatory Position: Note that no revision number to RG 1.200 is identified in the draft document. Add a one-sentence statement or footnote regarding the process by which the appropriate revision can be identified.
No change has been made. The applicable revision of RG 1.200 is the same revision that is germane to the application in question (i.e.,
the latest revision unless a grace period is in effect).
the latest revision unless a grace period is in effect).
: 23. Page 13,     NEI     As written, the first sentence could be interpreted as equating Level 2           The requested change has been Section              analysis with LERF. Suggest changing the sentence to read Evaluations of         made.
: 23.
2.3.2,              CDF and LERF should be performed to support any risk-informed changes Second              to TS.
Page 13, Section 2.3.2, Second Paragraph NEI As written, the first sentence could be interpreted as equating Level 2 analysis with LERF. Suggest changing the sentence to read Evaluations of CDF and LERF should be performed to support any risk-informed changes to TS.
Paragraph
The requested change has been made.
: 24. 2.3.1       NEI     In Section 2.3.1, which discusses PRA technical acceptability and the             The DG is intended to reference applicability of RG 1.200 to risk-informed technical specifications, the         the revision of RG 1.200 reference to RG 1.200 needs to be specific to the current revision, which will   appropriate for the application in be Revision 2, effective April 2010.                                             question (i.e., the current revision unless a grace period is in effect).
: 24.
6
2.3.1 NEI In Section 2.3.1, which discusses PRA technical acceptability and the applicability of RG 1.200 to risk-informed technical specifications, the reference to RG 1.200 needs to be specific to the current revision, which will be Revision 2, effective April 2010.
The DG is intended to reference the revision of RG 1.200 appropriate for the application in question (i.e., the current revision unless a grace period is in effect).  


#  Section /   Comment                                       Comment                                 NRC Response Reference  Source
7 Section /
: 25. Page 13,   NEI     The discussion on technical adequacy should be enhanced to include           The requested change has been Section            guidance on expectations for capability categories for the supporting         made.
Reference Comment Source Comment NRC Response
2.3.1, Last        requirements from RG 1.200. A concise discussion is given in DG-1226 and Paragraph          could be replicated here.
: 25.
: 26. Page 13,   NEI,   From cover letter: Section 2.3.2 states that the scope of the analysis should The paragraph has been updated Section    PWROG  include all hazard groups unless it can be shown that the contribution from   to address the comment.
Page 13, Section 2.3.1, Last Paragraph NEI The discussion on technical adequacy should be enhanced to include guidance on expectations for capability categories for the supporting requirements from RG 1.200. A concise discussion is given in DG-1226 and could be replicated here.
2.3.2,              the specific hazard group is insignificant. The wording of the commissions Second              phased approach to PRA scope states that contributors that are significant Paragraph          to the decision should be addressed using an assessment to the PRA standards. The wording in the DG should be revised to be consistent with the commission position. Otherwise, with current definitions relative to insignificant, it could be concluded that the risk contributor must be quantified before it can be determined if quantification is unnecessary.
The requested change has been made.
: 26.
Page 13, Section 2.3.2, Second Paragraph
: NEI, PWROG From cover letter: Section 2.3.2 states that the scope of the analysis should include all hazard groups unless it can be shown that the contribution from the specific hazard group is insignificant. The wording of the commissions phased approach to PRA scope states that contributors that are significant to the decision should be addressed using an assessment to the PRA standards. The wording in the DG should be revised to be consistent with the commission position. Otherwise, with current definitions relative to insignificant, it could be concluded that the risk contributor must be quantified before it can be determined if quantification is unnecessary.
From specific comments: For improved clarity, the second sentence should be revised to read The scope of the analysis should include those hazard groups that have a significant impact on the decision.
From specific comments: For improved clarity, the second sentence should be revised to read The scope of the analysis should include those hazard groups that have a significant impact on the decision.
: 27. 2.3.2       PWROG   In the second paragraph, there is a requirement for external event analyses   This comment has been unless the issue can be shown insignificant to the decision.                 addressed, in part, by changes to There are three changes:                                                     the paragraph in question. The
The paragraph has been updated to address the comment.
: 1) Since formal analytical models may not be available, analysis should be staff does not agree with other replaced by risk-informed assessment.                                       parts of the comment, or they are
: 27.
: 2) Change the term insignificant to not significant. Insignificant can be addressed elsewhere in this DG or interpreted as negligible, and not significant can be interpreted as small. RG 1.174.
2.3.2 PWROG In the second paragraph, there is a requirement for external event analyses unless the issue can be shown insignificant to the decision.
There are three changes:
: 1) Since formal analytical models may not be available, analysis should be replaced by risk-informed assessment.
: 2) Change the term insignificant to not significant. Insignificant can be interpreted as negligible, and not significant can be interpreted as small.
The use of the phrase not significant is more appropriate.
The use of the phrase not significant is more appropriate.
: 3) It should be acknowledged that while NFPA-805 fire PRA models are conservative, alternate more realistic models are acceptable for other risk informed application, such as risk informed Technical Specification initiatives.
: 3) It should be acknowledged that while NFPA-805 fire PRA models are conservative, alternate more realistic models are acceptable for other risk informed application, such as risk informed Technical Specification initiatives.
: 28. Page 13,   NEI     For clarity, in the first sentence, involved should be revised to read     The requested change has been Section            involved in the change.                                                    made.
This comment has been addressed, in part, by changes to the paragraph in question. The staff does not agree with other parts of the comment, or they are addressed elsewhere in this DG or RG 1.174.
2.3.3.1 7
: 28.
Page 13, Section 2.3.3.1 NEI For clarity, in the first sentence, involved should be revised to read involved in the change.
The requested change has been made.  


#  Section /   Comment                                   Comment                                   NRC Response Reference    Source
8 Section /
: 29. Page 14,     NEI     For clarity, AOT should be revised to read extended AOT in the           No change has been made. The Section              parenthetical phrase.                                                        use of the term "extended AOT" 2.3.3.1,                                                                                          assumes the proposed change is First Bullet                                                                                      to extend an existing AOT, which in Second                                                                                        is overly restrictive.
Reference Comment Source Comment NRC Response
Bullet List
: 29.
: 30. Page 14,     NEI     Section A.1.3.2 should be changed to Section A-1.3.2.                   The requested change was made.
Page 14, Section 2.3.3.1, First Bullet in Second Bullet List NEI For clarity, AOT should be revised to read extended AOT in the parenthetical phrase.
Section 2.3.3.1, Third to Last Full Paragraph on Page
No change has been made. The use of the term "extended AOT" assumes the proposed change is to extend an existing AOT, which is overly restrictive.
: 31. Page 15,    NEI     Section A.2 should be changed to Section A-1.3.2.                       No change has been made. The Section                                                                                          existing reference is correct.
: 30.
2.3.3.2, Last Paragraph
Page 14, Section 2.3.3.1, Third to Last Full Paragraph on Page NEI Section A.1.3.2 should be changed to Section A-1.3.2.
: 32. Page 16,    NEI     This section should refer to the guidance in the ASME/ANS PRA Standard       The staff does not agree with this Section              and otherwise discourage the use of pre-solved cutsets.                     comment. The DG already 2.3.3.4,                                                                                          invokes the standard through RG Second                                                                                            1.200.
The requested change was made.
Paragraph
: 31.
: 33. Page 16,     NEI     It is recommended that the last sentence of Item 1 be changed to read If   The requested change was made.
Page 15, Section 2.3.3.2, Last Paragraph NEI Section A.2 should be changed to Section A-1.3.2.
Section              the risk evaluation is marginal or exceeds the guidelines for a proposed AOT 2.3.4, Item          increase and the systems involve those needed for shutdown (e.g. residual 1                    heat removal systems, auxiliary feedwater systems, service water systems),
No change has been made. The existing reference is correct.
: 32.
Page 16, Section 2.3.3.4, Second Paragraph NEI This section should refer to the guidance in the ASME/ANS PRA Standard and otherwise discourage the use of pre-solved cutsets.
The staff does not agree with this comment. The DG already invokes the standard through RG 1.200.
: 33.
Page 16, Section 2.3.4, Item 1
NEI It is recommended that the last sentence of Item 1 be changed to read If the risk evaluation is marginal or exceeds the guidelines for a proposed AOT increase and the systems involve those needed for shutdown (e.g. residual heat removal systems, auxiliary feedwater systems, service water systems),
the licensee may want to perform comparative risk evaluations of continued power operation versus plant shutdown.
the licensee may want to perform comparative risk evaluations of continued power operation versus plant shutdown.
: 34. Page 17,     NEI     For licensees considering the zero maintenance option, it may be helpful to No change has been made. This Section              add the following after the second sentence: Note that the stated           portion of the Regulatory Guide is 2.3.4, Item          acceptance criteria are based on a baseline CDF with nominal expected       not being revised, and it is not 2                    equipment unavailabilities.                                                clear what value this note adds.
The requested change was made.
: 35. Page 17,     NEI     Change Regulatory Positions 2.3.7 and 4.1 to Regulatory Positions 2.3.7   The text has been changed to only Section              and 4.                                                                      cross-reference Section 2.3.7.
: 34.
2.3.4, Item 5
Page 17, Section 2.3.4, Item 2
8
NEI For licensees considering the zero maintenance option, it may be helpful to add the following after the second sentence: Note that the stated acceptance criteria are based on a baseline CDF with nominal expected equipment unavailabilities.
No change has been made. This portion of the Regulatory Guide is not being revised, and it is not clear what value this note adds.
: 35.
Page 17, Section 2.3.4, Item 5
NEI Change Regulatory Positions 2.3.7 and 4.1 to Regulatory Positions 2.3.7 and 4.
The text has been changed to only cross-reference Section 2.3.7.  


#  Section / Comment                                     Comment                                         NRC Response Reference Source
9 Section /
: 36. Page 18, NEI     Section 2.3.5 of the Regulatory Position should refer to NUREG-1855 and             A reference to NUREG-1855 has Section          describe how uncertainty analysis should support risk-informed technical             been added. Further guidance has 2.3.5            specification applications. A hypothetical example of application of NUREG-         not been added, as it is available 1855 to a completion time extension was prepared for a joint NRC/EPRI               in the NUREG itself.
Reference Comment Source Comment NRC Response
workshop on NUREG-1855 and may be helpful to consult.
: 36.
: 37. Page 18, NEI     From cover letter: Section 2.3.5 discusses sensitivity and uncertainty               The sentence in question has Section          analysis related to assumptions. A final sentence has been added, noting             been changed to read: Therefore, 2.3.5,            that the applicant will have to provide substantial justification relative to tier the Tier 2 and Tier 3 aspects of Second to        2 and tier 3 controls. It is not clear why this sentence was added, and, as a       such TS changes should be Last              substantial addition to the previous wording, the need for this change should       justified as robust and adequate to Paragraph        be explained, or it should be removed. Further, regulatory guides are not           control the resulting potential for regulations and should not use requirements language (e.g., will have to).        significant risk increases.
Page 18, Section 2.3.5 NEI Section 2.3.5 of the Regulatory Position should refer to NUREG-1855 and describe how uncertainty analysis should support risk-informed technical specification applications. A hypothetical example of application of NUREG-1855 to a completion time extension was prepared for a joint NRC/EPRI workshop on NUREG-1855 and may be helpful to consult.
A reference to NUREG-1855 has been added. Further guidance has not been added, as it is available in the NUREG itself.
: 37.
Page 18, Section 2.3.5, Second to Last Paragraph NEI PWROG From cover letter: Section 2.3.5 discusses sensitivity and uncertainty analysis related to assumptions. A final sentence has been added, noting that the applicant will have to provide substantial justification relative to tier 2 and tier 3 controls. It is not clear why this sentence was added, and, as a substantial addition to the previous wording, the need for this change should be explained, or it should be removed. Further, regulatory guides are not regulations and should not use requirements language (e.g., will have to).
From specific comments: The last sentence in this paragraph should be revised to remove the phrase applicant will have to. The industry suggests revising the sentence to read Applicant-provided justification may be appropriate.
From specific comments: The last sentence in this paragraph should be revised to remove the phrase applicant will have to. The industry suggests revising the sentence to read Applicant-provided justification may be appropriate.
PWROG  C. Regulatory Position: Section 2.3.5: In the last paragraph, there is an added sentence at the end of Section 2.3.5 (Page 18) that reads However, the applicant will have to provide substantial justification. In this new sentence, substantial justification is versus the deleted wording that said, may be more difficult to justify. This appears to be changing this requirement. The added sentence is not helpful. The meaning of substantial is unclear. The initial portion of the paragraph states that the expectation for the Tier 2 and Tier 3 activity is expected to be robust. This is in the Sensitivity and Uncertainty Section. Tier 2 assessments evaluate the potential for high risk configurations. What is being requested in addition to Tier 2 requirements or (a)(4) of the Maintenance Rule to assess and manage risk? Delete final sentence and replace with a clear alternative, such as: If such circumstances are expected, the utility should provide justification to ensure that the risk consequences of multiple entries into longer duration CTs is properly considered.
C. Regulatory Position: Section 2.3.5: In the last paragraph, there is an added sentence at the end of Section 2.3.5 (Page 18) that reads However, the applicant will have to provide substantial justification. In this new sentence, substantial justification is versus the deleted wording that said, may be more difficult to justify. This appears to be changing this requirement. The added sentence is not helpful. The meaning of substantial is unclear. The initial portion of the paragraph states that the expectation for the Tier 2 and Tier 3 activity is expected to be robust. This is in the Sensitivity and Uncertainty Section. Tier 2 assessments evaluate the potential for high risk configurations. What is being requested in addition to Tier 2 requirements or (a)(4) of the Maintenance Rule to assess and manage risk? Delete final sentence and replace with a clear alternative, such as: If such circumstances are expected, the utility should provide justification to ensure that the risk consequences of multiple entries into longer duration CTs is properly considered.
9
The sentence in question has been changed to read: Therefore, the Tier 2 and Tier 3 aspects of such TS changes should be justified as robust and adequate to control the resulting potential for significant risk increases.


#  Section /   Comment                                 Comment                                     NRC Response Reference    Source
10 Section /
: 38. 2.3.6       PWROG   C. Regulatory Position, Section 2.2.1: In the second bullet, the following is The requested change has been deleted: to compensate for weaknesses in design. In the first sentence in   made.
Reference Comment Source Comment NRC Response
Section 2.3.6, second paragraph, the same words were not deleted.
: 38.
2.3.6 PWROG C. Regulatory Position, Section 2.2.1: In the second bullet, the following is deleted: to compensate for weaknesses in design. In the first sentence in Section 2.3.6, second paragraph, the same words were not deleted.
Consistency. Remove the words in the second paragraph of Section 2.3.6 and replace them with the words similar to those in Section 2.2.1.
Consistency. Remove the words in the second paragraph of Section 2.3.6 and replace them with the words similar to those in Section 2.2.1.
: 39. Page 20,     NEI,   It appears that 10 CFR 50.65(a)(4) is inadvertently mistyped as 10 CFR       The requested change has been Section      Exelon  50.65(a)(3).                                                                 made.
The requested change has been made.
2.3.7.2, Key Component 1 Heading
: 39.
: 40. 2.3.7.2     PWROG   Item 3 on page 20 refers to TS action statement, which is not consistent   The requested change has been with the terminology in NUREGs 1430-1434.                                    made.
Page 20, Section 2.3.7.2, Key Component 1 Heading
: NEI, Exelon It appears that 10 CFR 50.65(a)(4) is inadvertently mistyped as 10 CFR 50.65(a)(3).
The requested change has been made.
: 40.
2.3.7.2 PWROG Item 3 on page 20 refers to TS action statement, which is not consistent with the terminology in NUREGs 1430-1434.
Revise TS action statement, to TS Action, to be consistent with the terminology in NUREGs 1430-1434.
Revise TS action statement, to TS Action, to be consistent with the terminology in NUREGs 1430-1434.
10
The requested change has been made.


#  Section / Comment                                           Comment                                         NRC Response Reference Source
11 Section /
: 41. 2.3.7     NEI     Section 2.3.7 discusses configuration control and the Configuration Risk                   The staff does not agree with the Management Program (CRMP). As noted in the DG, the CRMP is met though                     commenters concern. No change reliance on 10 CFR 50.65(a)(4). This regulatory position has been in effect since         has been made with regard to this shortly after the promulgation of (a)(4). The NRC is currently performing a regulatory     issue.
Reference Comment Source Comment NRC Response
analysis to justify expansion of the scope of (a)(4) to include non-internal events initiators. However, this regulatory analysis is not complete. The DG is unclear in its discussion of PRA technical adequacy relative to the applicability of RG 1.200 on the tier 3 process; however, NRC staff has recently stated their intent that RG 1.200 should be applied to tier 3. This is a significant revision to an accepted regulatory position, and is neither justified nor appropriate. We request that the staff clarify the final RG to clearly state that RG 1.200 does not apply to tier 3. 10 CFR 50.65(a)(4) and its NRC-endorsed implementation guidance (RG 1.182) allow quantitative, qualitative or blended approaches to address risk assessment and management.
: 41.
2.3.7 NEI Section 2.3.7 discusses configuration control and the Configuration Risk Management Program (CRMP). As noted in the DG, the CRMP is met though reliance on 10 CFR 50.65(a)(4). This regulatory position has been in effect since shortly after the promulgation of (a)(4). The NRC is currently performing a regulatory analysis to justify expansion of the scope of (a)(4) to include non-internal events initiators. However, this regulatory analysis is not complete. The DG is unclear in its discussion of PRA technical adequacy relative to the applicability of RG 1.200 on the tier 3 process; however, NRC staff has recently stated their intent that RG 1.200 should be applied to tier 3. This is a significant revision to an accepted regulatory position, and is neither justified nor appropriate. We request that the staff clarify the final RG to clearly state that RG 1.200 does not apply to tier 3. 10 CFR 50.65(a)(4) and its NRC-endorsed implementation guidance (RG 1.182) allow quantitative, qualitative or blended approaches to address risk assessment and management.
Further, the scope of initiators is limited to internal events. These attributes reflect overt decisions made by the NRC in endorsing the guidance and reflect limits on the state of practice and modeling for configuration control purposes. All plants use their Level 1 internal events PRA in some fashion in their (a)(4) program, and most plants are approaching general conformance with the internal events portion of RG 1.200.
Further, the scope of initiators is limited to internal events. These attributes reflect overt decisions made by the NRC in endorsing the guidance and reflect limits on the state of practice and modeling for configuration control purposes. All plants use their Level 1 internal events PRA in some fashion in their (a)(4) program, and most plants are approaching general conformance with the internal events portion of RG 1.200.
However, the PRA is not expected to be compared to RG 1.200 specifically for the purposes of (a)(4) compliance. To invoke RG 1.200, Revision 2, or to make an unspecified reference to RG 1.200 in the context of tier 3 assessments will create substantial problems for the CRMP and (a)(4). The following problems would be created: Rulemaking and Directives Branch November 3, 2009 Page 3
However, the PRA is not expected to be compared to RG 1.200 specifically for the purposes of (a)(4) compliance. To invoke RG 1.200, Revision 2, or to make an unspecified reference to RG 1.200 in the context of tier 3 assessments will create substantial problems for the CRMP and (a)(4). The following problems would be created: Rulemaking and Directives Branch November 3, 2009 Page 3
: 1. The expectations for the CRMP would diverge greatly from the (a)(4) program due to different initiators, and different expectations for quantification.
: 1.
: 2. The CRMP expectation would essentially obviate the ongoing (a)(4) regulatory analysis, and is potentially subject to the same regulatory analysis considerations under 10 CFR 109, since it is a new regulatory position.
The expectations for the CRMP would diverge greatly from the (a)(4) program due to different initiators, and different expectations for quantification.
: 2.
The CRMP expectation would essentially obviate the ongoing (a)(4) regulatory analysis, and is potentially subject to the same regulatory analysis considerations under 10 CFR 109, since it is a new regulatory position.
: 3. Invoking RG 1.200, Revision 2 into CRMP suggests an expectation for quantification of fire and external events (including seismic) risk. This capability at a level to support (a)(4) is many years away. Significant problems with conservatism in fire PRAs would lead to skewed risk assessments and incorrect risk management actions. The fire PRA will not be usable for decision-making involving comparison to internal events until the existing models are made more realistic. NRC staff involved in the ongoing (a)(4) regulatory analysis have stated that fire can be addressed qualitatively. Further, no plants have external events (seismic) PRAs meeting RG 1.200, Revision 2, and the pilot application is not yet complete.
: 3. Invoking RG 1.200, Revision 2 into CRMP suggests an expectation for quantification of fire and external events (including seismic) risk. This capability at a level to support (a)(4) is many years away. Significant problems with conservatism in fire PRAs would lead to skewed risk assessments and incorrect risk management actions. The fire PRA will not be usable for decision-making involving comparison to internal events until the existing models are made more realistic. NRC staff involved in the ongoing (a)(4) regulatory analysis have stated that fire can be addressed qualitatively. Further, no plants have external events (seismic) PRAs meeting RG 1.200, Revision 2, and the pilot application is not yet complete.
11
The staff does not agree with the commenters concern. No change has been made with regard to this issue.


#  Section /   Comment                                   Comment                                     NRC Response Reference    Source
12 Section /
: 42. 2.4         PWROG   The next to the last paragraph on page 21 discusses PRA-informed             In the sentence indicated, PRA-results, which should be risk-informed results.                             informed results has been Revise PRA-informed results to risk informed results.                     changed to PRA results. An occurrence of PRA-informed results in the appendix was also modified.
Reference Comment Source Comment NRC Response
: 43. 2.4         PWROG   Item 1 on page 22 refers to TS AOT entry, which is not consistent with the   The requested change has been terminology in NUREGs 1430-1434.                                              made.
: 42.
2.4 PWROG The next to the last paragraph on page 21 discusses PRA-informed results, which should be risk-informed results.
Revise PRA-informed results to risk informed results.
In the sentence indicated, PRA-informed results has been changed to PRA results. An occurrence of PRA-informed results in the appendix was also modified.
: 43.
2.4 PWROG Item 1 on page 22 refers to TS AOT entry, which is not consistent with the terminology in NUREGs 1430-1434.
Revise TS AOT entry, to TS Condition entry, to be consistent with the terminology in NUREGs 1430-1434.
Revise TS AOT entry, to TS Condition entry, to be consistent with the terminology in NUREGs 1430-1434.
: 44. Page 22,     NEI,   The industry appreciates that, for one-time changes, different acceptance     No change has been made.
The requested change has been made.
Quantitative Exelon  guidelines that are consistent with NUMARC 93-01 have been added.             Additional flexibility is provided for Acceptance          However, for permanent changes, the acceptance guidelines are structured       one-time changes since Guidelines          differently. For example, for one-time changes, there are two ICCDP           compensatory measures may be thresholds (i.e., 10-6 and 10-7). This is consistent with both NUMARC 93-01   implemented. For permanent and the Region 2/Region 3 demarcations from RG 1.174 in that the limit is     changes, compensatory measures treated as permeable if additional actions are taken. However, for the        are not typically specified in the permanent changes, only one threshold is specified (i.e., ICCDP of 10-6),     TS, and the additional flexibility in even though ICCDPs below that threshold are allowed without any risk           risk is not justified.
: 44.
management actions under licensee (a)(4) programs. This is inconsistent with both NUMARC 93-01 and RG 1.174, and is overly restrictive, especially for CTs that are expected to be utilized infrequently. Furthermore, for permanent changes, the CDF/LERF guidelines are also applied. The CDF/LERF guidelines, along with risk monitoring, ensure that there is not a large change in risk to the public over time and should provide a sufficient backstop to allow for an additional ICCDP/ICLERP threshold to be applied, with appropriate considerations of risk management actions that might be applicable above an ICCDP of 10-6 or an ICLERP of 10-7
Page 22, Quantitative Acceptance Guidelines
: 45. Page 27,     NEI     It should be specified that RG 1.200, Revision 2 is the revision referenced   The revision number has been References,          throughout this DG.                                                            removed, consistent to the Reference                                                                                          responses on other similar 13                                                                                                  comments on both DG-1226 and DG-1227.
: NEI, Exelon The industry appreciates that, for one-time changes, different acceptance guidelines that are consistent with NUMARC 93-01 have been added.
12
However, for permanent changes, the acceptance guidelines are structured differently. For example, for one-time changes, there are two ICCDP thresholds (i.e., 10-6 and 10-7). This is consistent with both NUMARC 93-01 and the Region 2/Region 3 demarcations from RG 1.174 in that the limit is treated as permeable if additional actions are taken. However, for the permanent changes, only one threshold is specified (i.e., ICCDP of 10-6),
even though ICCDPs below that threshold are allowed without any risk management actions under licensee (a)(4) programs. This is inconsistent with both NUMARC 93-01 and RG 1.174, and is overly restrictive, especially for CTs that are expected to be utilized infrequently. Furthermore, for permanent changes, the CDF/LERF guidelines are also applied. The CDF/LERF guidelines, along with risk monitoring, ensure that there is not a large change in risk to the public over time and should provide a sufficient backstop to allow for an additional ICCDP/ICLERP threshold to be applied, with appropriate considerations of risk management actions that might be applicable above an ICCDP of 10-6 or an ICLERP of 10-7 No change has been made.
Additional flexibility is provided for one-time changes since compensatory measures may be implemented. For permanent changes, compensatory measures are not typically specified in the TS, and the additional flexibility in risk is not justified.
: 45.
Page 27, References, Reference 13 NEI It should be specified that RG 1.200, Revision 2 is the revision referenced throughout this DG.
The revision number has been removed, consistent to the responses on other similar comments on both DG-1226 and DG-1227.  


#  Section /   Comment                                     Comment                               NRC Response Reference  Source
13 Section /
: 46. Page A-2,   NEI     For clarity, insert the word equipment after the word given.           No change has been made. The Section A-                                                                                    requested change is not 1.1, Fourth                                                                                    necessary.
Reference Comment Source Comment NRC Response
Bullet
: 46.
: 47. Page A-2,   NEI     For clarity, insert the words the plant after the words shutting down. The requested change has been Section A-                                                                                    made.
Page A-2, Section A-1.1, Fourth Bullet NEI For clarity, insert the word equipment after the word given.
1.1, Fifth Bullet
No change has been made. The requested change is not necessary.
: 48. A-1.3.2.2   PWROG   Typo: Section A-1.3.2.2, paragraph 2, page A-5, OC should be QC.       The requested change has been Revise OC to QC.                                                      made.
: 47.
13}}
Page A-2, Section A-1.1, Fifth Bullet NEI For clarity, insert the words the plant after the words shutting down.
The requested change has been made.
: 48.
A-1.3.2.2 PWROG Typo: Section A-1.3.2.2, paragraph 2, page A-5, OC should be QC.
Revise OC to QC.
The requested change has been made.}}

Latest revision as of 05:48, 14 January 2025

Staffs Responses to Public Comments
ML100910313
Person / Time
Issue date: 05/31/2011
From: Don Helton
NRC/RES/DRA
To:
O'Donnell, Edward, RES/DE/RGB 251-7455
Shared Package
ML100910007 List:
References
DG-1227 RG 1.177, Rev. 1
Download: ML100910313 (13)
v • d • e


Text

1 Response to Public Comments on Draft Regulatory Guide (DG) -1227 An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications" Proposed Revision 2 of RG 1.174 A notice that Draft Regulatory Guide, DG-1227 (Proposed Revision 1 of RG 1.177) was available for public comment was published in the Federal Register on September 3, 2009 on page 74 FR 45655. The Public Comment period ended November 3, 2009.

Comments were received from the organizations listed below. The NRC has combined the comments and NRC staff disposition in the following table.

Section /

Reference Comment Source Comment NRC Response

1.

General NEI A key companion document, RG 1.200, An Approach for determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities, is listed in the references without a revision number; this should be corrected to specifically reference Revision 2. Referencing RG 1.200 without a revision number is not conducive to maintaining regulatory stability, as issuance of future revisions of RG 1.200 could appreciably alter the implications of portions of RG 1.177 without any prior NRC or public review. The lack of a specific revision number in the reference could also lead to ambiguity in the guidance during the implementation period for any future revisions to RG 1.200, as during this time, it would not be clear which revision is intended in the reference.

The staff does not agree with the commenter. Regulatory Guide 1.177 references the revision of RG 1.200 appropriate for the application in question (i.e., the current revision unless a grace period is in effect).

2.

General

NEI, PWROG Suggest changing allowed outage time to completion time and surveillance test interval to surveillance frequency throughout the document to achieve consistency with NUREGs 1430-1434 as noted in the footnote on Page 2.

The requested changes have been made throughout the document.

3.

Page 4, Purpose of this Regulatory Guide, Last Paragraph NEI While the guide at hand focuses on changes to AOTs and STIs, it is understood that other type changes to the Technical Specifications can also utilize the guidance; this should be better emphasized in this section. It is recommended that the second sentence of this paragraph, which deals with other types of TS changes, be moved to the end of the section as a stand-alone paragraph.

The requested change has been made.

2 Section /

Reference Comment Source Comment NRC Response

4.

Page 4, Purpose of this Regulatory Guide, Last Paragraph NEI The last sentence in this paragraph, which discusses the possibility of additional or revised guidance for plants licensed under 10 CFR 52, should be removed. This issue is being addressed in separate venues, and a Commission-level decision may be forthcoming. The industry suggests that such statements not be incorporated into regulatory guides until the decisionmaking process is complete.

The staff does not agree with the commenters concern. No change has been made.

5.

Page 4, Scope of Regulatory Guide, Last Paragraph NEI The industry appreciates that the RG has been revised to explicitly address both permanent and one-time changes.

No change requested.

6.

Page 4, Scope of Regulatory Guide, Last Paragraph Exelon In this section, the word "permanent" has been deleted from the phrase, "proposed permanent TS changes" in the first sentence and a revised last sentence now states: "... This regulatory guide provides guidance for both permanent and one time only (AOT)changes to TS." In the past, this RG has been specifically applicable ONLY to proposed permanent Technical Specifications (TS) changes. One-time TS changes (e.g., Allowed Outage Time (AOT) extensions, Notices of Enforcement Discretion (NOEDs), exigent TS changes), were not formally subject to the guidance of this RG, and expanding the scope provides useful guidance for evaluation of such non-permanent changes. However, in expanding the scope of applicability, does the inclusion of the parenthetical "(AOT)" in the last sentence limit one-time only changes to just AOT changes? Exelon requests clarification whether this draft RG is specifically not applicable to NOEDs or exigent TS changes.

The parenthetical around AOT was removed. The staff believes that the existing wording already clarifies that exigent TS changes are included, while NOEDs are not.

3 Section /

Reference Comment Source Comment NRC Response

7.

Page 4, "Relationshi p to Other Guidance Documents" Exelon DG-1 227 does not refer to either RG 1.200 or NUREG-1 855. Both of those documents establish expectations for PRA scope and technical acceptability for risk-informed applications in a broad context. Exelon considers it important for an RG for particular types of applications such as DG-1 227 to provide additional guidance regarding how the other relevant guidance documents are to be applied.

Regulatory Guide 1.200 is in fact referenced in the DG. To augment the existing reference, a paragraph has been added in the Relationship to Other Guidance Documents section. A reference to NUREG-1855 has also been added. Also, the pending revision to RG 1.174 addresses the nexus between application-specific RGs (e.g., 1.177) and the guidance provided by RG 1.200 and NUREG-1855.

8.

Page 5, Risk-Informed Philosophy, Third Paragraph NEI There appears to be a philosophical difference in approach between DG-1227 and DG-1226 (RG 1.174) when it comes to treatment of the traditional engineering aspects of risk-informed decisionmaking. RG 1.174 states that PRA can provide insights into whether the extent of defense-in-depth is appropriate to ensure protection of public health and safety. However, to address the unknown and unforeseen failure mechanisms or phenomena, traditional defense-in-depth considerations should be used or maintained.

DG-1227, on the other hand, states that risk analysis techniques can be, and are encouraged to be, used to help ensure and show that these

[traditional engineering] principles are met. This seems inconsistent; further, Section 2.2.1 of DG-1227 appears to actually use the PRA to provide insights, not to show that the principles are met, which is more consistent with the RG 1.174 approach.

We do not agree that the two DGs are inconsistent in this respect. In fact, the very sentence quoted from DG-1227 also appears in DG-1226. No change has been made.

9.

Page 5, Risk-Informed Philosophy NEI While this section discusses the five principles, there is no specific reference to Figure 1, which depicts these principles, and the term Integrated decisionmaking is never used. It is recommended Figure 1 be specifically referenced, and that Integrated Decisionmaking as portrayed in Figure 1 also be mentioned.

A pointer to Figure 1 has been added. Integrated decisionmaking is already mentioned in the second paragraph of this section.

10.

Page 5, Risk-Informed Philosophy, Items 2 and 3 NEI For items 2 and 3 change Regulatory Position 2.2 to Regulatory Position 2.2.1 and Regulatory Position 2.2.2, respectively.

The requested change was made.

4 Section /

Reference Comment Source Comment NRC Response

11.

Page 5, Risk-Informed Philosophy, Item 3 PWROG Discussion under Risk-Informed Philosophy, item 3: There is slightly inconsistent with other sections by leaving out the words of this regulatory guide after Regulatory Position 2.2. Revise to be consistent.

The requested change was made.

12.

Page 6, Element 1 NEI The implied stipulation for the licensee to directly describe how the proposed TS change meets the objectives of the PRA Policy Statement would be more clear if a reference were made to the guidance under Element 1 of Section C, Regulatory Position. It is recommended the second to last sentence be revised to read The licensee should describe the proposed change and how it meets the objectives of the Commissions PRA Policy Statement, including enhanced decisionmaking, more efficient use of resources, and reduction of unnecessary burden as provided below in Sections 1.1.1, 1.1.2, and 1.1.3.

The sentence is unchanged from the current active version. The subsequent sentence states "Regulatory Position 1 describes element 1 in more detail." This sentence provides the necessary reference to details in the referenced sections. A similar sentence is used in each of the subsequent elements 2-4, so making this element unique and referring to specific subsections of the regulatory position would introduce inconsistency.

13.

Page 8, Section 2, First Paragraph NEI The implied need for the applicant to directly evaluate compliance with the NRC Safety Goal Policy Statement rather than just with the acceptance guidelines of the regulatory guide seems an unnecessary burden for the licensee. The first sentence should be revised to read The licensee should examine the proposed TS change to verify that it meets existing applicable rules and regulations as expressed through the acceptance guidelines given in this regulatory guide.

This does not represent a change from the currently published version of the RG. No change has been made to the DG.

14.

Page 9, Element 2, Last Paragraph NEI The meaning of STS should be defined.

The acronym STS (Standard Technical Specifications) is already defined on page 1.

15.

Page 10, Section 2.2.1, Fourth Bullet NEI The fourth bullet should be modified unless it is deemed credible for changes to AOTs to introduce a new CCF mode, as opposed to changing the magnitude of CCF rates.

No change has been made.

Technical specification changes could introduce new CCF mechanisms, since AOT changes are not the only changes covered by the Regulatory Guide.

5 Section /

Reference Comment Source Comment NRC Response

16.

Page 12, Section 2.3, Tier 3 Heading NEI To achieve better consistency with established (a)(4) guidance, the industry suggests changing the first sentence of this section such that evaluated before performing any maintenance activity is replaced with assessed and managed.

The requested change has been made.

17.

Page 12, Section 2.3, Tier 3 Heading NEI Add and demonstration that a licensee meets the (a)(4) requirements is sufficient for Tier 3 assessments to the end of the first sentence of the first paragraph.

No change has been made. The staff disagrees with the notion that the (a)(4) program alone always satisfies Tier 3.

18.

Page 12,

'Tier 3," 1 st paragraph, and Page 20, "Key Component 1,"Item #3 Section 2.3.7, Exelon "Contemporaneous Configuration Control," refers to Regulatory Position 2.3, Tier 3, and with the revisions to Regulatory Position 2.3, these discussions imply that the licensee program for compliance with 10 CFR 50.65(a)(4) should provide an adequate approach to meeting Tier 3. The section of DG-1227 that originally specified inclusion of Configuration Risk Management Program (CRMP) in the Administrative Section of the TS has been removed.

However, the discussion describing when to invoke the CRMP is still linked to TS AOTs, whereas 10 CFR 50.65(a)(4) does not link the performance of any aspect of risk assessment to TS. Section 2.4 requires implementation of a "risk-informed plant configuration control program" as a prerequisite for AOT changes. In this regard:

Exelon requests clarification whether a licensee program which is in compliance with 10 CFR 50.65(a)(4) meets the total intent of the "risk-informed plant configuration control program" prescribed in Section 2.4.

Exelon requests clarification whether licensee programs for compliance with 10 CFR 50.65(a)(4) are adequate "as-is" for supporting TS changes pursuant to DG-1227. Are there additional requirements vis-a-vis Structures, Systems, or Components (SSCs) with TS AOTs?

Exelon recommends that if additional requirements are intended, then DG-1227 should be clear with respect to the scope of those SSCs. In other words, do those additional requirements apply to all TS SSCs with AOTs, or just the SSCs with AOTs that have been changed pursuant to DG-1 227?

No change has been made. The intent of the minor changes to the Tier 3 program discussion is to identify that the (a)(4) risk assessment is adequate to satisfy that portion of Tier 3. Other existing items in the Regulatory Guide (such as consideration of external events risk, procedural controls, use for risk-informed TS AOTs, etc.) are beyond the (a)(4) requirements and are retained.

6 Section /

Reference Comment Source Comment NRC Response

19.

Page 12, Section 2.3, Tier 3 Heading NEI The last two paragraphs under the Tier 3 heading do not appear to be relevant to Tier 3 exclusively. As such, the information should be relocated to the appropriate sections on Tiers 1, 2, or 3; alternatively, a separate heading could provide additional clarity. Additionally, the discussion should be revised to specify applicability of Regulatory Position 2.3.1 to any tiers. It is suggested that Regulatory Position 2.3.1 applies only to Tier 1.

Several changes were made to address this comment. The two paragraphs in question were moved to the end of the Section 2.3 introduction, the requested change to the first sentence under Tier 3 was made, and a new final sentence was added to the first paragraph under Section 2.3.1.

20.

Page 12, Section 2.3, Tier 3

Heading, Second Paragraph NEI In the second sentence, in general should be changed to specifically.

The requested change was made.

Note that the paragraph in question was moved up in response to the previous comment.

21.

Page 12, Section 2.3.1

NEI, PWROG, Exelon In the heading for Section 2.3.1, the word acceptability should be changed to adequacy to achieve consistency with other NRC documents, such as RG 1.200. This terminology should be similarly aligned throughout the document.

The requested change has been made.

22.

2.3.1 PWROG C. Regulatory Position: Note that no revision number to RG 1.200 is identified in the draft document. Add a one-sentence statement or footnote regarding the process by which the appropriate revision can be identified.

No change has been made. The applicable revision of RG 1.200 is the same revision that is germane to the application in question (i.e.,

the latest revision unless a grace period is in effect).

23.

Page 13, Section 2.3.2, Second Paragraph NEI As written, the first sentence could be interpreted as equating Level 2 analysis with LERF. Suggest changing the sentence to read Evaluations of CDF and LERF should be performed to support any risk-informed changes to TS.

The requested change has been made.

24.

2.3.1 NEI In Section 2.3.1, which discusses PRA technical acceptability and the applicability of RG 1.200 to risk-informed technical specifications, the reference to RG 1.200 needs to be specific to the current revision, which will be Revision 2, effective April 2010.

The DG is intended to reference the revision of RG 1.200 appropriate for the application in question (i.e., the current revision unless a grace period is in effect).

7 Section /

Reference Comment Source Comment NRC Response

25.

Page 13, Section 2.3.1, Last Paragraph NEI The discussion on technical adequacy should be enhanced to include guidance on expectations for capability categories for the supporting requirements from RG 1.200. A concise discussion is given in DG-1226 and could be replicated here.

The requested change has been made.

26.

Page 13, Section 2.3.2, Second Paragraph

NEI, PWROG From cover letter: Section 2.3.2 states that the scope of the analysis should include all hazard groups unless it can be shown that the contribution from the specific hazard group is insignificant. The wording of the commissions phased approach to PRA scope states that contributors that are significant to the decision should be addressed using an assessment to the PRA standards. The wording in the DG should be revised to be consistent with the commission position. Otherwise, with current definitions relative to insignificant, it could be concluded that the risk contributor must be quantified before it can be determined if quantification is unnecessary.

From specific comments: For improved clarity, the second sentence should be revised to read The scope of the analysis should include those hazard groups that have a significant impact on the decision.

The paragraph has been updated to address the comment.

27.

2.3.2 PWROG In the second paragraph, there is a requirement for external event analyses unless the issue can be shown insignificant to the decision.

There are three changes:

1) Since formal analytical models may not be available, analysis should be replaced by risk-informed assessment.
2) Change the term insignificant to not significant. Insignificant can be interpreted as negligible, and not significant can be interpreted as small.

The use of the phrase not significant is more appropriate.

3) It should be acknowledged that while NFPA-805 fire PRA models are conservative, alternate more realistic models are acceptable for other risk informed application, such as risk informed Technical Specification initiatives.

This comment has been addressed, in part, by changes to the paragraph in question. The staff does not agree with other parts of the comment, or they are addressed elsewhere in this DG or RG 1.174.

28.

Page 13, Section 2.3.3.1 NEI For clarity, in the first sentence, involved should be revised to read involved in the change.

The requested change has been made.

8 Section /

Reference Comment Source Comment NRC Response

29.

Page 14, Section 2.3.3.1, First Bullet in Second Bullet List NEI For clarity, AOT should be revised to read extended AOT in the parenthetical phrase.

No change has been made. The use of the term "extended AOT" assumes the proposed change is to extend an existing AOT, which is overly restrictive.

30.

Page 14, Section 2.3.3.1, Third to Last Full Paragraph on Page NEI Section A.1.3.2 should be changed to Section A-1.3.2.

The requested change was made.

31.

Page 15, Section 2.3.3.2, Last Paragraph NEI Section A.2 should be changed to Section A-1.3.2.

No change has been made. The existing reference is correct.

32.

Page 16, Section 2.3.3.4, Second Paragraph NEI This section should refer to the guidance in the ASME/ANS PRA Standard and otherwise discourage the use of pre-solved cutsets.

The staff does not agree with this comment. The DG already invokes the standard through RG 1.200.

33.

Page 16, Section 2.3.4, Item 1

NEI It is recommended that the last sentence of Item 1 be changed to read If the risk evaluation is marginal or exceeds the guidelines for a proposed AOT increase and the systems involve those needed for shutdown (e.g. residual heat removal systems, auxiliary feedwater systems, service water systems),

the licensee may want to perform comparative risk evaluations of continued power operation versus plant shutdown.

The requested change was made.

34.

Page 17, Section 2.3.4, Item 2

NEI For licensees considering the zero maintenance option, it may be helpful to add the following after the second sentence: Note that the stated acceptance criteria are based on a baseline CDF with nominal expected equipment unavailabilities.

No change has been made. This portion of the Regulatory Guide is not being revised, and it is not clear what value this note adds.

35.

Page 17, Section 2.3.4, Item 5

NEI Change Regulatory Positions 2.3.7 and 4.1 to Regulatory Positions 2.3.7 and 4.

The text has been changed to only cross-reference Section 2.3.7.

9 Section /

Reference Comment Source Comment NRC Response

36.

Page 18, Section 2.3.5 NEI Section 2.3.5 of the Regulatory Position should refer to NUREG-1855 and describe how uncertainty analysis should support risk-informed technical specification applications. A hypothetical example of application of NUREG-1855 to a completion time extension was prepared for a joint NRC/EPRI workshop on NUREG-1855 and may be helpful to consult.

A reference to NUREG-1855 has been added. Further guidance has not been added, as it is available in the NUREG itself.

37.

Page 18, Section 2.3.5, Second to Last Paragraph NEI PWROG From cover letter: Section 2.3.5 discusses sensitivity and uncertainty analysis related to assumptions. A final sentence has been added, noting that the applicant will have to provide substantial justification relative to tier 2 and tier 3 controls. It is not clear why this sentence was added, and, as a substantial addition to the previous wording, the need for this change should be explained, or it should be removed. Further, regulatory guides are not regulations and should not use requirements language (e.g., will have to).

From specific comments: The last sentence in this paragraph should be revised to remove the phrase applicant will have to. The industry suggests revising the sentence to read Applicant-provided justification may be appropriate.

C. Regulatory Position: Section 2.3.5: In the last paragraph, there is an added sentence at the end of Section 2.3.5 (Page 18) that reads However, the applicant will have to provide substantial justification. In this new sentence, substantial justification is versus the deleted wording that said, may be more difficult to justify. This appears to be changing this requirement. The added sentence is not helpful. The meaning of substantial is unclear. The initial portion of the paragraph states that the expectation for the Tier 2 and Tier 3 activity is expected to be robust. This is in the Sensitivity and Uncertainty Section. Tier 2 assessments evaluate the potential for high risk configurations. What is being requested in addition to Tier 2 requirements or (a)(4) of the Maintenance Rule to assess and manage risk? Delete final sentence and replace with a clear alternative, such as: If such circumstances are expected, the utility should provide justification to ensure that the risk consequences of multiple entries into longer duration CTs is properly considered.

The sentence in question has been changed to read: Therefore, the Tier 2 and Tier 3 aspects of such TS changes should be justified as robust and adequate to control the resulting potential for significant risk increases.

10 Section /

Reference Comment Source Comment NRC Response

38.

2.3.6 PWROG C. Regulatory Position, Section 2.2.1: In the second bullet, the following is deleted: to compensate for weaknesses in design. In the first sentence in Section 2.3.6, second paragraph, the same words were not deleted.

Consistency. Remove the words in the second paragraph of Section 2.3.6 and replace them with the words similar to those in Section 2.2.1.

The requested change has been made.

39.

Page 20, Section 2.3.7.2, Key Component 1 Heading

NEI, Exelon It appears that 10 CFR 50.65(a)(4) is inadvertently mistyped as 10 CFR 50.65(a)(3).

The requested change has been made.

40.

2.3.7.2 PWROG Item 3 on page 20 refers to TS action statement, which is not consistent with the terminology in NUREGs 1430-1434.

Revise TS action statement, to TS Action, to be consistent with the terminology in NUREGs 1430-1434.

The requested change has been made.

11 Section /

Reference Comment Source Comment NRC Response

41.

2.3.7 NEI Section 2.3.7 discusses configuration control and the Configuration Risk Management Program (CRMP). As noted in the DG, the CRMP is met though reliance on 10 CFR 50.65(a)(4). This regulatory position has been in effect since shortly after the promulgation of (a)(4). The NRC is currently performing a regulatory analysis to justify expansion of the scope of (a)(4) to include non-internal events initiators. However, this regulatory analysis is not complete. The DG is unclear in its discussion of PRA technical adequacy relative to the applicability of RG 1.200 on the tier 3 process; however, NRC staff has recently stated their intent that RG 1.200 should be applied to tier 3. This is a significant revision to an accepted regulatory position, and is neither justified nor appropriate. We request that the staff clarify the final RG to clearly state that RG 1.200 does not apply to tier 3. 10 CFR 50.65(a)(4) and its NRC-endorsed implementation guidance (RG 1.182) allow quantitative, qualitative or blended approaches to address risk assessment and management.

Further, the scope of initiators is limited to internal events. These attributes reflect overt decisions made by the NRC in endorsing the guidance and reflect limits on the state of practice and modeling for configuration control purposes. All plants use their Level 1 internal events PRA in some fashion in their (a)(4) program, and most plants are approaching general conformance with the internal events portion of RG 1.200.

However, the PRA is not expected to be compared to RG 1.200 specifically for the purposes of (a)(4) compliance. To invoke RG 1.200, Revision 2, or to make an unspecified reference to RG 1.200 in the context of tier 3 assessments will create substantial problems for the CRMP and (a)(4). The following problems would be created: Rulemaking and Directives Branch November 3, 2009 Page 3

1.

The expectations for the CRMP would diverge greatly from the (a)(4) program due to different initiators, and different expectations for quantification.

2.

The CRMP expectation would essentially obviate the ongoing (a)(4) regulatory analysis, and is potentially subject to the same regulatory analysis considerations under 10 CFR 109, since it is a new regulatory position.

3. Invoking RG 1.200, Revision 2 into CRMP suggests an expectation for quantification of fire and external events (including seismic) risk. This capability at a level to support (a)(4) is many years away. Significant problems with conservatism in fire PRAs would lead to skewed risk assessments and incorrect risk management actions. The fire PRA will not be usable for decision-making involving comparison to internal events until the existing models are made more realistic. NRC staff involved in the ongoing (a)(4) regulatory analysis have stated that fire can be addressed qualitatively. Further, no plants have external events (seismic) PRAs meeting RG 1.200, Revision 2, and the pilot application is not yet complete.

The staff does not agree with the commenters concern. No change has been made with regard to this issue.

12 Section /

Reference Comment Source Comment NRC Response

42.

2.4 PWROG The next to the last paragraph on page 21 discusses PRA-informed results, which should be risk-informed results.

Revise PRA-informed results to risk informed results.

In the sentence indicated, PRA-informed results has been changed to PRA results. An occurrence of PRA-informed results in the appendix was also modified.

43.

2.4 PWROG Item 1 on page 22 refers to TS AOT entry, which is not consistent with the terminology in NUREGs 1430-1434.

Revise TS AOT entry, to TS Condition entry, to be consistent with the terminology in NUREGs 1430-1434.

The requested change has been made.

44.

Page 22, Quantitative Acceptance Guidelines

NEI, Exelon The industry appreciates that, for one-time changes, different acceptance guidelines that are consistent with NUMARC 93-01 have been added.

However, for permanent changes, the acceptance guidelines are structured differently. For example, for one-time changes, there are two ICCDP thresholds (i.e., 10-6 and 10-7). This is consistent with both NUMARC 93-01 and the Region 2/Region 3 demarcations from RG 1.174 in that the limit is treated as permeable if additional actions are taken. However, for the permanent changes, only one threshold is specified (i.e., ICCDP of 10-6),

even though ICCDPs below that threshold are allowed without any risk management actions under licensee (a)(4) programs. This is inconsistent with both NUMARC 93-01 and RG 1.174, and is overly restrictive, especially for CTs that are expected to be utilized infrequently. Furthermore, for permanent changes, the CDF/LERF guidelines are also applied. The CDF/LERF guidelines, along with risk monitoring, ensure that there is not a large change in risk to the public over time and should provide a sufficient backstop to allow for an additional ICCDP/ICLERP threshold to be applied, with appropriate considerations of risk management actions that might be applicable above an ICCDP of 10-6 or an ICLERP of 10-7 No change has been made.

Additional flexibility is provided for one-time changes since compensatory measures may be implemented. For permanent changes, compensatory measures are not typically specified in the TS, and the additional flexibility in risk is not justified.

45.

Page 27, References, Reference 13 NEI It should be specified that RG 1.200, Revision 2 is the revision referenced throughout this DG.

The revision number has been removed, consistent to the responses on other similar comments on both DG-1226 and DG-1227.

13 Section /

Reference Comment Source Comment NRC Response

46.

Page A-2, Section A-1.1, Fourth Bullet NEI For clarity, insert the word equipment after the word given.

No change has been made. The requested change is not necessary.

47.

Page A-2, Section A-1.1, Fifth Bullet NEI For clarity, insert the words the plant after the words shutting down.

The requested change has been made.

48.

A-1.3.2.2 PWROG Typo: Section A-1.3.2.2, paragraph 2, page A-5, OC should be QC.

Revise OC to QC.

The requested change has been made.

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