ML18311A360

NRC Comments on Appendix D Revision 0g Rev. 1

ML18311A360
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Issue date:	11/07/2018
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NRC Comments on NEI 96-07, Appendix D, Revision 0g On October 26, 2018, the Nuclear Energy Institute (NEI) submitted to the U.S. Nuclear Regulatory Commission (NRC), NEI 96-07, Appendix D, Revision 0g (ADAMS Accession No. ML18310A433). The chart below documents the NRC staffs comments on this latest version of NEI 96-07, Appendix D. Below the chart are 4 comments that either: 1) require clarification of a new edit to the guidance; or 2) requests a response to a comment previously provided to NEI in the NRCs action item response document for the draft NEI 96-07, Appendix D, Revision 0g (ADAMS Accession Number ML18282A044).

This document will be used to support a Category 2 public meeting with NEI to discuss these comments on November 14, 2018.

Comment Color Key:

GREEN = NRC has no further comments.

RED = Apparent conflict with regulatory infrastructure; NRC/NEI to gain alignment on what needs to change and why it is necessary.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

1. 1 N/A See Item #1. The staff does not believe that the RIS is superseded General by Appendix D. Therefore, the edit to the executive summary is incorrect.

2. General 2 N/A Addressed in Item #7. No further comments

3. 3 N/A Addressed in Items #13 & No further comments General

1. 40.

4. General 4 N/A See Item #28a. No further comments

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

5. 5 N/A See Item #70. This comment was not addressed in Appendix D.

General The staff will address this comment within its endorsement of Appendix D.

6. Executive A1 C NRC needs to identify the No further comments Summary additional part(s) of the Supplement that need to be incorporated.

Supplement 1 to RIS 2002-22 is primarily a guidance document for technical guidance (i.e., the preparation of qualitative assessments and the topics that should be considered therein), not licensing (i.e.,

50.59) guidance. Only the guidance in Section 2.2 is related to 50.59, which has already been incorporated into Section 4.3 of Appendix D.

7. 1.1 A2 C To be incorporated No further comments

8. 1.2 A3 E To be incorporated No further comments

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

9. 1.2 A4 E Suggested addition not No further comments pertinent, but final sentence to be removed.

10. 4.2 A5 C The purpose of the No further comments CAUTION is to ensure the user understands that the guidance in the main body of NEI 96-07 still applies and/or must be considered.

Suggested text will be added.

11. 4.2 A6 C To be incorporated No further comments

12. 4.2 A7 C The conclusions in the No further comments examples will be changed to reflect the phrase "does not screen in for the aspect or topic within the section/subsection" (or equivalent) in place of "not adverse."

13. 4.2 A8 C See Item #28a. No further comments

14. 4.2.1.1 A9 E Subject text to be removed, No further comments not moved.

15. 4.2.1.1 A10 C Subject text to be removed. No further comments

16. 4.2.1.1 A11 C To be incorporated No further comments

17. 4.2.1.1 A12 C The suggested language The parenthetical (i.e.,

will need to be adjusted to software CCF likelihood =

acknowledge that the 0) is incorrect and needs to

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement "engineering evaluation" in be removed from the edits.

this case would be a Otherwise, the edit is qualitative assessment (as acceptable.

described in Supplement 1 to RIS 2002-22), which is used in the Evaluation phase, not in the Screen phase.

The information in the subsequent paragraph is related and perhaps the paragraphs could be combined.

18. 4.2.1.1 A13 C In the Screen section, No further comments engineering evaluations will be changed to "engineering/technical information supporting the change. Note that the term "qualitative assessment" and its process do not apply in the Screen phase, but do apply in the Evaluation phase (as identified in Supplement 1 to RIS 2002-22).

19. 4.2.1.1 A14 C Suggested wording to be To be consistent with the slightly modified and added deletion of the quoted text in

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement as an example at the end of comment A9 and A10, the the sentence. edited language must also be deleted.

20. 4.2.1.1 A15 C Will add "e.g." at the No further comments beginning of the items within the parentheses.

21. Example 4-1 A16 C Parenthetical phrase to be No further comments removed.

22. Example 4-1 A17 C Identified text will be No further comments removed and two sentences created.

23. Example 4-1 A18 C Parenthetical phrase to be No further comments removed.

24. Example 4-2 A19 C Although the observation See item A20 stated in the NRC comment could be true, this example does not represent an actual plant or an actual licensing basis of a facility.

This example simply illustrates the case in which there are "no design functions."

Add, In this case, the licensee has determined there are NO design functions

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

25. Example 4-2 A20 C See response to item #19. Fails to consider NEI 96-07, Section 3.3, which states, Design functions may be performed by safety-related SSCs or nonsafety-related SSCs and include functions that, if not performed, would initiate a transient or accident that the plant is required to withstand.

26. Example 4-3 A21 C Example 4-3 will be No further comments reworked to address the new approach proposed in addressing Item #12.

27. 4.2.1.1 A22 E NRC needs to identify a Comment not addressed but specific type of comment is an "combination" not covered enhancement.

by current examples.

28. 4.2.1.1 A23 C The current sentence will be No further comments replaced with the associated guidance from NEI 01-01, Section 4.3.3, four bullets at the end of the 1st paragraph.

29. Example 4-4 A24 C Erroneous conclusion basis No further comments will be corrected.

30. Example 4-4 A25 C (1) According to the Resolution on A25b would currently endorsed guidance resolve this comment.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement in NEI 01-01, Section 4.3.3, first bullet at the end of the first paragraph, this type of impact is NOT ADVERSE.

Namely, although multiples failures will be created, only one (design) function (i.e.,

provide feedwater) is affected.

The text will be modified to clarify this point.

31. Example 4-4 A25 C (2) "Independence" (in its Was not addressed because licensing application) is not Option 2 in the example is applicable to non-safety- counter to the guidance related SSCs. In this case, inserted Reductions in the two main feedwater trains redundancy, diversity, are provided for operational separation, or convenience and design independence of a UFSAR-considerations (e.g., pump described design function sizing).

An easy fix is to change the The "what if" scenario conclusion from not adverse presented in the comment to adverse. Reasoning is regarding probability and its that reduction in redundancy impact on reliability does of the design function is need to be considered, but adverse.

not as part of this digital specific aspect. Namely,

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement impacts on reliability are addressed in the guidance contained in NEI 96-07, Rev. 1, Section 4.2.1.

See note at the beginning of the Screen Response.

32. Example 4-4 A25 C (3) See reponse to Item See A25b

1. 25b.

33. Example 4-5 A26 C According to the currently Same issue persists as in endorsed guidance in NEI the previous comment. See 01-01, Section 4.3.3, first comment A25b.

bullet at the end of the first paragraph, this type of impact is NOT ADVERSE.

Namely, although multiple failures will be created, only one (design) function (i.e.,

control temperature) is affected.

The text will be modified to clarify that only one design function is affected.

34. Example 4-6 A27 C "Independence" (in its Based on the inserted quote licensing application) is not this example should be applicable to non-safety- revised, Reductions in the related SSCs. There is no redundancy, diversity,

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement design function to maintain separation, or physical separation of the independence of a UFSAR-multiple control systems that described design function typically exists for most safety-related SSCs. An easy fix is to change the conclusion from not adverse This example (as with other to adverse. Reasoning is examples) is intended to that reduction in illustrate a digital specific independence of the design aspect and is not meant to function is adverse.

be inclusive of everything considered in the 10 CFR 50.59 review of an activity.

35. 4.2.1.2 A28 C This comment, which gives NEI chose to move forward the option to retain this with this section included in section, is contrary to the Appendix. Therefore, General Comment #4 (see NRC withdraws this Item #D), which comment.

recommends the removal of this section.

This guidance does not address a generic guidance issue with NEI 96-07, Rev.

1. The purpose of this section is to provide digital-specific application of the related guidance from NEI

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement 96-07, Rev. 1, Section 4.2.1.2.

Furthermore, NEI 01-01, Section 4.3.4 contains guidance for HSI.

Eliminating this section from Appendix D would result in the incomplete inclusion of pertinent guidance when NEI 01-01 is superseded.

36. 4.2.1.2 A28 C The acronym HSI is already No further comments used in this section. The term "Human Factors Evaluation (HFE)" will be added in a manner similar to that used in Section 4.3 to describe a Qualitative Assessment.

37. 4.2.1.2 A29 E The intent of this guidance NRC staff understands is to provide a process for NEIs approach.

the Screen practitioner to perform the HFE within the Screen if the practioner is sufficiently knowledgeable to do so. This approach is supported by NEI 96-07,

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement Rev. 1, Section 4.2.1, subsection titled "Screening for Adverse Effects" in the 5th paragraph, 1st sentence.

38. 4.2.1.2 A29 E NEI 96-07, Rev. 1 contains No further comments guidance on how to "convert" a technical result into a licensing result (i.e.,

adverse or not adverse) by "comparing" the new condition with the licensing condition ((refer to the diesel start time example embedded in NEI 96-07, Rev. 1, Section 4.2.1, subsection titled "Screening for Adverse Effects").

39. 4.2.1.2 A30 E Detailed technical guidance NRC staff understands is provided in the references NEIs approach.

(e.g., NUREG-0700 and NUREG/CR-6947).

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

40. 4.2.1.2 A30 E As with all 50.59 activities, NRC staff understands the appropriate subject NEIs approach. No further matter experts are expected comments.

to be consulted or participate in developing/creating the technical bases used in the 50.59 process, as necessary.

41. 4.2.1.2 A31 C The word may will be No further comments deleted.

42. 4.2.1.2 A31 C There is no inconsistency No further comments with NEI 96-07 and related conclusions in Examples 4-8a and 4-8b.

However, use of the word "negative" in the HFE conclusion was inappropriate and will be removed, and the outcomes restated as statements of final conditions, not as "negative" or "positive."

Then, as described in NEI 96-07, the Screen uses those final conditions to determine the type of impact

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement (i.e., positive, negative, or none) on design functions (refer to the diesel start time example embedded in NEI 96-07, Rev. 1, Section 4.2.1, subsection titled "Screening for Adverse Effects").

43. 4.2.1.2 A32 E Replace the word "final" with No further comments "next." However, the first two steps are clearly identified as being the "two-step HSI assessment," so there is NO "third" HSI assessment step.

44. 4.2.1.2 A33 C The process and examples No further comments correctly implement NEI 96-07, Rev. 1 guidance.

However, use of the word "negative" in the HFE conclusion was inappropriate and will be removed, and the outcomes restated as statements of final conditions, not as "negative" or "positive."

Then, as described in NEI 96-07, the Screen uses those final conditions to

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement determine the type of impact (i.e., positive, negative, or none) on design functions (refer to the diesel start time example embedded in NEI 96-07, Rev. 1, Section 4.2.1, subsection titled "Screening for Adverse Effects").

45. Example 4-8a A34 C The HFE outcome is an Even though the word increase in response time. negative has been However, there is no removed from this example, response time element the staff does not agree that within the identified design the remainder of our functions in this example. comments from previous Therefore, although more discussions have been time will be needed to addressed in example 4-8a.

perform the design function, there is no adverse impact on the ability to actually perform the described design function. The not adverse conclusion is correct in this example.

If a response time element was included as part of the design function description, then the new response time, NOT the INCREASE in the

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement response time, would be compared with the response time requirement in the licensing basis to determine the impact.)

46. Example 4-8a A35 C The process and example Even though the word correctly implement NEI 96- negative has been 07, Rev. 1 guidance. removed from this example, the staff does not agree that However, use of the word the remainder of our "negative" in the HFE comments from previous conclusion was discussions have been inappropriate and will be addressed in example 4-8a.

removed, and the outcomes restated as statements of final conditions, not as "negative" or "positive."

Then, as described in NEI 96-07, the Screen uses those final conditions to determine the type of impact (i.e., positive, negative, or none) on design functions (refer to the diesel start time example embedded in NEI 96-07, Rev. 1, Section 4.2.1, subsection titled "Screening for Adverse Effects").

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement Propose to change subject sentence to, The HFE evaluation determined that the modification increased in the operators time to respond by requiring four actions instead of one action.

47. Example 4-8b A36 & A37 C The process and example No further comments correctly implement NEI 96-07, Rev. 1 guidance.

However, use of the word "negative" in the HFE conclusion was inappropriate and will be removed, and the outcomes restated as statements of final conditions, not as "negative" or "positive."

Then, as described in NEI 96-07, the Screen uses those final conditions to determine the type of impact (i.e., positive, negative, or none) on design functions (refer to the diesel start time example embedded in NEI 96-07, Rev. 1, Section 4.2.1,

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement subsection titled "Screening for Adverse Effects").

Propose to change [A36]

subject sentence to, The HFE evaluation concluded that this modification could result in the operator choosing not to have certain parameters displayed, impacting their ability to monitor the plant and detect changes. In addition, altering the information displayed and the organization of the information will impact the operators understanding of how the information relates to system performance.

This impact on understanding will also impact the operators ability to assess the situation and plan an appropriate response.

Propose to change [A37]

subject sentence to, The

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement HFE evaluation determined that the modification increased in the operators time to respond by requiring four actions instead of one action.

48. Example 4-8b A38 & A39 C [A38] This example (as with No further comments other examples) is intended to illustrate a digital specific aspect and is not meant to be inclusive of everything considered in the 10 CFR 50.59 review of an activity.

[A39] Same as response to item 36.

49. 4.3 A40 C "Expansion" and Acceptable with the "paraphrasing" will be exception of the eliminated except for parenthetical that states if locations where required by such design functions exist digital-specific guidance. on pages D14 and D15.

50. 4.3 A40 C NRC needs to identify the Staff provided language additional part(s) of the from RIS 2002-22, Supplement that need to be Supplement 1 to be incorporated. incorporated in Appendix D (ADAMS Accession No. ML18310A203). The

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement Supplement 1 to RIS 2002- following language should 22 is primarily a document be added to the FMEA for technical guidance (i.e., section under 4.3.6 after the the preparation of qualitative NEI quote:

assessments and the topics that should be considered In addition to failures therein), not licensing (i.e., caused by software, other 50.59) guidance. Only the effects of a digital guidance in Section 2.2 is modification could create related to 50.59, which has new results of malfunctions already been incorporated (e.g., combining functions, into Section 4.3 of Appendix creating new interactions D. with other systems, changing response time).

For example, if previously separate functions are combined in a single digital device, the failure analysis should consider whether single failures that could previously have affected only individual design functions can now affect multiple design functions.

51. 4.3 A41 C Guidance for how to perform No further comments a qualitative assessment (which is a technical assessment) is not pertinent

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement in a licensing-based guidance document. NEI 16-16 (or equivalent) is the appropriate document for inclusion of technical guidance.

52. 4.3 A41 C NRC needs to identify the No further comments specific additional part(s) of the Supplement that need to be incorporated.

Supplement 1 to RIS 2002-22 is primarily a document for technical guidance (i.e.,

the preparation of qualitative assessments and the topics that should be considered therein), not licensing (i.e.,

50.59) guidance. Only the guidance in Section 2.2 is related to 50.59, which has already been incorporated into Section 4.3 of Appendix D.

53. 4.3 A41 C Please clarify which No further comments restrictions on the applicability of the qualitative assessment so

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement that we consider everything NRC is considering.

54. 4.3 A42 C The phrase "qualitative No further comments assessment" will be clarified to reflect its use in Supplement 1 of RIS 2002-22 and made consistent throughout the document.

55. 4.3 A43 C NRC needs to identify the No further comments additional part(s) of the Supplement that need to be incorporated.

Supplement 1 to RIS 2002-22 is primarily a document for technical guidance (i.e.,

the preparation of qualitative assessments and the topics that should be considered therein), not licensing (i.e.,

50.59) guidance. Only the guidance in Section 2.2 is related to 50.59, which has already been incorporated into Appendix D, Sections 4.3.1, 4.3.2, 4.3.5 and 4.3.6.

56. 4.3.1 A44 C The Industry agrees the No further comments word "initiator" does not

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement exist in the 50.59 Regulation or in NEI 96-07, Rev. 1, Section 4.3.1. However, the NRC comment fails to identify that the word and consideration of "initiator" does exist in NEI 01-01, Section 4.4.1. Since NEI 01-01 is currently endorsed for use in completing 50.59 Evaluations for activities involving digital modifications, the inclusion of guidance in Appendix D, Section 4.3.1 regarding "initiators" is NOT "contrary to 50.59(c)(2)(i)."

57. 4.3.1 A44 C The Industry agrees with the No further comments second bullet point that a new initiator of an accident already evaluated in the UFSAR is considered in Evaluation question (i).

Evaluation question (i) considers ONLY those accidents previously evaluated in the UFSAR.

Contrast that with

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement Evaluation question (v) which deals with the creation of the possibility of new accidents. The guidance for Evaluation question (v) in NEI 96-07, Rev. 1, Section 4.3.5 contains the following statement: "A new initiator of an accident previously evaluated in the UFSAR is not a different type of accident."

58. 4.3.1 A45 C The Industry agrees that an No further comments increase in accident frequency can be for a multitude of reasons, including increases from "new" and/or "entirely different" initiators. Refer to the detailed basis provided in the Industry Response to Item #42a & #42b.

Propose to edit the subject sentence, After applying the generic guidance in NEI 96-07, Section 4.3.1 to identify any accidents

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement affected by the systems/components involved with the digital modification and, then examining the initiators of those accidents, the impact on the frequency of the initiator (and, hence, the accident itself) due to the digital modification can be assessed.

59. 4.3.1 A46 E See response to item #43. No further comments

60. Example 4-9 A47 & A48 C The example will be revised No further comments to indicate that there are no accidents related to the chillers.

61. 4.3.1 A49 E Consistent use of "software No further comments CCF" (vs. failure, etc.) will be addressed.

62. 4.3.1 A50 & A51 C Clarification of concepts was No further comments dispositioned and closed in April 2017 (see Public_Meeting_Items_and_

Actions (NEI9607AppD_06212017).

CCF outcomes of sufficiently low or not sufficiently low were

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement finalized in RIS 2002-22 Supplement 1 and are the only new information incorporated.

63. 4.3.1 and A52 & A53 C The Industry agrees that No further comments Example 4-12 meeting the requirements, etc. is in addition to all other considerations. This statement can be clarified to more clearly identify this fact.

64. 4.3.1 and A52 & A53 C See response to Item #47. No further comments Example 4-12

65. 4.3.1 (and A54 E Subsection on Human- No further comments other similar System Interface locations) Assessment to be deleted.

66. 4.3.1 (and A55 E Subsection on Human- No further comments other similar System Interface locations) Assessment to be deleted.

67. 4.3.2 A56 E The Industry disagrees with The wording from the RIS the final phrase in the Supplement used to statement: "...reductions in address comment A40 redundancy, diversity and should be included in independence are general section 4.3.2 of Appendix D, technical concerns for digital with the exception of the modifications and not parenthetical added to the specifically tied to any first paragraph. See page single evaluation criteria D14.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement under 10 CFR 50.59"

[emphasis added to the pertinent phrase].

In Supplement 1 to RIS 2002-22, Section 3, 2nd paragraph, near the end of the first sentence (which discussed the four terms) footnote No. 4 is included immediately following the last term.

Footnote No. 4 clearly indicates that these terms refer to ONLY NEI 96-07, Section 4.3.2, which provides guidance for ONLY 10 CFR 50.59(c)(2)(ii).

The discussion of these terms is located correctly and will not be relocated to the beginning of Section 4.3 as suggested.

68. 4.3.2 A57 C Agree with the observation; No further comments general comment does not provide suggested changes.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

69. 4.3.2 A58 C The suggested NRC No further comments comment to add the phrase "of the design function" seems inappropriate because the suggested phrase is not in the reference.

It is unclear how the second sentence is inconsistent with NEI 96-07, Rev. 1 or RIS 2002-22, Supplement 1.

70. 4.3.2 A59 C Propose to remove No further comments discussions of these four terms.

71. 4.3.2 A60 C Propose to remove No further comments discussions of these four terms.

72. 4.3.2 A61 C Propose to remove No further comments discussions of these four terms.

73. 4.3.2 A62 C Agree to remove paragraph. No further comments

74. 4.3.2 A63 C Propose to remove No further comments discussions of these four terms.

75. 4.3.2 A64 C Propose to remove No further comments discussions of these four terms.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

76. 4.3.2 A65 C (1) This comment is not No further comments related to 50.59 guidance.

Furthermore, the NRC statement that "Generally, only malfunctions are identified in the UFSAR, not the initiators of the malfunctions" is not representative of most UFSARs. Namely, most UFSARs do identify most, sometimes all, malfunction (and accident) initiators.

77. 4.3.2 A65 C (2) The Industry agrees with No further comments the second point that a new initiator of a malfunction already evaluated in the UFSAR is considered in Evaluation question (ii).

Evaluation question (ii) considers ONLY those malfunctions previously evaluated in the UFSAR.

The Industry agrees that an increase in malfunction likelihood can be for a multitude of reasons,

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement including increases from "new" and/or "entirely different" initiators.

Propose to replace If none of the components/systems involved with the digital modification are identified as affecting a malfunction initiator previously identified in the UFSAR, then there is no attributable impact on the likelihood of occurrence of a malfunction. with, After applying the generic guidance in NEI 96-07, Section 4.3.2 to identify any malfunctions affected by the systems/components involved with the digital modification and, then examining the initiators of those malfunctions, the impact on the likelihood of the malfunction due to the digital modification can be assessed.

78. 4.3.2 A65 C (3) Evaluation questions (ii) This comment has been and (vi) address different addressed in the guidance

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement aspects so their "thresholds" but not addressed in the cannot be compared. example. Example 4-13 still uses the term Malfunction Initiators throughout the example.

79. 4.3.2 A66 & A67 C Clarification of concepts was No further comments dispositioned and closed in April 2017 (see Public_Meeting_Items_and_

Actions (NEI9607AppD_06212017).

CCF outcomes of sufficiently low or not sufficiently low were finalized in RIS 2002-22 Supplement 1 and are the only new information incorporated.

80. 4.3.5 A68 C The full text from No further comments Supplement 1 to RIS 2002-22, Section 2.2, subsection 10 CFR 50.59(c)(2)(v) will be included.

For completeness, the appropriate full text from Supplement 1 to RIS 2002-22, Section 2.2 will be

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement added in 4.3.1, 4.3.2, and 4.3.6.

81. 4.3.5 A69 C Failure likelihood will be No further comments used throughout Appendix D in lieu of "software CCF" for consistency with RIS 2002-22, Supplement 1.

82. 4.3.5 A70 E Delete phrase. No further comments

83. 4.3.5 A71 E To be incorporated No further comments

84. 4.3.5 A72 C Note will be removed. No further comments

85. Example 4-16 A73 C Example will be reworked to No further comments match the guidance.

86. Example 4-16 A74 C Use of the phrase No further comments "qualitative assessment" will be clarified and made consistent.

87. Example 4-17 A75 C Example will be reworked to No further comments match the guidance.

88. 4.3.6 A76 C Section 4.3.6 will be No further comments, as retained and is critical to the NEI has chosen to keep this application of 10 CFR 50.59 section in Appendix D.

to digital activities. NRC comments do not identify specific conflicts with 10 CFR 50.59 or associated regulatory basis and guidance documents.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement

89. 4.3.6 A77 C In the "review" subsection, Page D-55, the sentence add the scope of below needs to be deleted "supporting UFSAR or revised to meet 50.59 analyses..." from NEI 96-07, (c)(2)(vi) as follows:

Rev. 1, Definition 3.12, Discussion section, first For these cases, this bullet, in the discussion of Evaluation criterion also needs safety analyses. to consider the impact this potential failure creates on a malfunction of an SSC important to safety with a different result than any previously evaluated in the final safety analysis report

90. 4.3.6 A78 C Comment does not provide No further comments specific evidence of misplaced context or specific misinterpretation.

While it would be ideal to refer to NEI 96-07, Rev.1, the importance of the quoted definitions and discussion highlights is critical to the proper application of 10 CFR 50.59 to digital activities. Specific conclusions of concern to

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement the staff have not been identified.

91. 4.3.6 A79 C This concern is addressed The staff will need to in the preceding discussions address this item in their and in Steps 2 and 5 of endorsement of Appendix D.

Section 4.3.6, in which all As written, the guidance Design Functions are does not indicate that this considered. Appendix should only be used for digital modifications due to the uniqueness aspects of digital technology.

92. 4.3.6 A80 C Yes, 10 CFR 50.59(c)(2)(vi) The staff provided language states Create a possibility to address this comment for a malfunction of an SSC (ADAMS Accession No.

important to safety with a ML18282A044). This different result than any language was not included previously evaluated in the in the Introduction to the final safety analysis report Determination of Safety (as updated). The results Analysis Result Impact in the UFSAR are presented section of the revision to in the safety analyses as Appendix D. The staff will defined in NEI 96-07, Rev. note this issue as an 1, Sec. 3.12. This is distinct exception in its from the broader descriptive endorsement of Appendix D.

material contained in the balance of the UFSAR, e.g.

descriptions of a components failure. NEI

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement 96-07, Rev. 1, Sec. 4.3.6 begins with, Malfunctions of SSCs are generally postulated as potential single failures to evaluate plant performance with the focus being on the result of the malfunction rather than the cause or type of malfunction. [emphasis added] An SSCs functional level is generally too low to independently represent a malfunction result as discussed in NEI 96-07.

93. 4.3.6 A81 C See response to item #73. PDC and GDC provides incomplete consideration of design basis function.

Design Basis function is defined in NEI 96-07.

94. 4.3.6 A82 C The referenced text relates No further comments to Section 4.3.2 in NEI 96-07, Rev. 1 and would not be considered as part of Section 4.3.6.

95. 4.3.6 A83 C The interdependent No further comments activities being discussed are not "compensatory

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement actions." The actions being discussed are actions associated with the as-designed SSC. For example, a new digital system could be equipped with a "reset" button. If the operating procedure contains steps for manipulation of the reset button, then those instructions are NOT compensatory actions.

However, if after utilizing the reset button, the SSC still does not function properly and OTHER actions NOT COVERED by any other procedure are developed in response to or to address the degraded condition of the SSC, then those newly-developed actions would be compensatory actions.

These types of activities (i.e., compensatory actions) are not unique to digital and would be addressed in

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement accordance with the guidance in NEI 96-07, Rev.

1 (e.g., Section 4.3.2, Example 4, and Section 4.4).

96. 4.3.6 A84 C Section 4.3.6.2 does not The staff provided language exist in NEI 96-07, Rev. 1. to address this comment The quote is from NEI 96- (ADAMS Accession No.

07, Rev. 1, Section 4.3.2, ML18282A044). This which is not pertinent in language was not included Section 4.3.6 (of NEI 96-07 in the following sections of or Appendix D). the revision to Appendix D.

The staff will note this issue Clarification/explanation of as an exception in its the comment/concern is endorsement of Appendix D.

needed.

This is also applicable for Step 6 and associated examples.

97. 4.3.6 A85 C [First Paragraph] The The staff provided language Industry agrees that "...there to address this comment will never be any 'pre- (ADAMS Accession No.

existing safety analysis' for ML18282A044). This new types of events created language was not included by a change." That specific in the following sections of condition is not the subject the revision to Appendix D.

of Evaluation question (vi), The staff will note this issue but would be addressed as an exception in its endorsement of Appendix D.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement using Evaluation question This is also applicable for (v). Step 6 and associated examples.

The guidance in Section 4.3.6 is correct for the cases in which a pre-existing safety analysis does exist.

The statement regarding "no safety analysis involved" is to remind the 50.59 practitioner of the limitations of this particular question.

98. 4.3.6 A85 C [Second Paragraph] The The staff provided language Industry agrees with to address this comment statements made in this (ADAMS Accession No.

paragraph, but no ML18282A044). This suggested changes are language was not included identified. in the following sections of the revision to Appendix D.

The staff will note this issue as an exception in its endorsement of Appendix D.

This is also applicable for Step 6 and associated examples.

99. 4.3.6 A85 C [Third Paragraph] The The staff provided language Industry agrees with to address this comment statements made in this (ADAMS Accession No.

paragraph, but no ML18282A044). This

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement suggested changes are language was not included identified. in the following sections of the revision to Appendix D.

The staff will note this issue as an exception in its endorsement of Appendix D.

This is also applicable for Step 6 and associated examples.

100. 4.3.6 A85 C [Fourth Paragraph] The staff provided language Consequences (i.e., to address this comment radiological dose) are (ADAMS Accession No.

addressed in two separate ML18282A044). This Evaluation questions: (iii) language was not included and (iv). ALL 50.59 in the following sections of questions must be the revision to Appendix D.

addressed for any proposed The staff will note this issue activity (with the exception as an exception in its of activities involving endorsement of Appendix D.

Methods of Evaluation). If This is also applicable for there is an impact on the Step 6 and associated radiological dose result, examples.

either question (iii) or (iv) will be the appropriate location, not question (vi).

101. 4.3.6 A86 C The statement will be No further comments changed from "meeting the acceptance criteria" to "being bounded."

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement 102. 4.3.6 A87 C See Industry Responses in This comment is applicable Items #79a and #79d.

to the revised version of Example 4-19, which states that Although the software CCF likelihood was determined to be not sufficiently low, there are no safety analyses that directly or indirectly credit the design basis function or contain expected responses of the radiation monitors.

This is inconsistent with NEI 96-07, Section 4.3.2, The safety analysis assumes certain design functions of SSCs in demonstrating the adequacy of design. Thus, certain design functions, while not specifically identified in the safety analysis, are credited in an indirect sense.

This guidance should be added to Appendix D.

103. 4.3.6 A88 C See Industry Response in No further comments Item #77.

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement There are no partial quotations.

104. 4.3.6 A89 C The effect of the increased No further comments feedwater flow was incorporated into the example, as illustrated in the second paragraph for the response to Step #6.

Consistent with the Six Step Process, a Design Function that is not associated with a Design Basis Function is identified as part of Step #2.

That Design Function is then addressed as part of Step #s 5 and 6.

105. 4.3.6 A90 C The Industry agrees with the In this example, previously technical content of the separate functions are comment. However, ONLY combined in a single digital the impact on malfunction device, then the evaluation results is addressed in needs to consider whether Evaluation question (vi), for single failures that could which the stated conclusion previously have disabled is correct. The other valid only individual functions can concerns identified in the now disable multiple comment would be functions. NEI 96-07 addressed in other pertinent illustrates this concern when it states:

NRC TYPE OF NRC NRC Comments on APPENDIX D COMMENT: INDUSTRY Revision 0g COMMENT SECTION C = Correction RESPONSE IDENTIFIER(S) E = Enhancement Evaluation questions, such as (i), (ii) and (v). An example of a change that would create the possibility for a malfunction with a different result is a substantial modification or upgrade to control station alarms, controls, or displays that are associated with SSCs important to safety that creates a new or common cause failure that is not bounded by previous analyses or evaluations.

106. 4.3.6 A91 C The statement will be Edit required -

changed from "meeting the Accident Analysis acceptance criteria" to Acceptance Criteria was "being bounded." removed to satisfy this comment, but replace with the language below that needs to be revised:

maximum allowed peak RCS pressure, maximum allowed secondary pressure, minimum allowed DNBR, maximum allowed peak linear heat rate and the dose consequences

Below are comments that either: 1) require clarification of a new edit to the guidance; or 2) requests a response to a comment previously provided to NEI in the NRCs action item response document for the draft NEI 96-07, Appendix D, Revision 0g (ADAMS Accession Number ML18282A044).

1. In section 4.2.1, the unsolicited revision (shown below) was submitted. Please clarify the need for this revision.

A 10 CFR 50.59 Evaluation is required for digital modifications that adversely affect design functions, or the methods used to perform or control design functions. There is no regulatory requirement for a proposed activity involving a digital modification to default (i.e., be mandatorily "forced") to an adverse conclusion.

2. In the Screening section, specifically in Example 4-4, reductions and redundancy should be considered in the examples to be consistent with the revision to the guidance. Otherwise, change option 2 to adverse.

3. In section 4.3.6, page D-60, the unsolicited revision (shown below) was submitted. The new text is underlined. Please clarify why this additional language was added.

If all design basis functions continue to be performed/satisfied, and there are no other design functions involved, then the proposed activity does NOT create the possibility for a malfunction of an SSC important to safety with a different result because no malfunction occurs. With no malfunction occurring, there cannot be a different result.

4. On Page D47, the staff noted that the referenced 63 FR 56106 is a proposed rule and not the final rule. NEI should reference final rules in its guidance, as there are differences between the proposed rule and final rule. Comment previously provided (ADAMS Accession Number ML18282A044).