TSTF-17-09, TSTF Comments on Draft Safety Evaluation for Traveler TSTF-546, Revision 0, Revise APRM Channel Adjustment Surveillance Requirement.

TSTF Comments on Draft Safety Evaluation for Traveler TSTF-546, Revision 0, Revise APRM Channel Adjustment Surveillance Requirement.

ML17205A444
Person / Time
Site:	Technical Specifications Task Force
Issue date:	07/24/2017
From:	Gustafson O, Morris J, Redd J, Vaughan J, Linda Williams Technical Specifications Task Force
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TSTF-17-09
Download: ML17205A444 (22)

Text

TECHNICAL SPECIFICATIONS TASK FORCE TSTF A JOINT OWNERS GROUP ACTIVITY July 24, 2017 TSTF-17-09 PROJ0753 Attn: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

TSTF Comments on Draft Safety Evaluation for Traveler TSTF-546, Revision 0, "Revise APRM Channel Adjustment Surveillance Requirement"

REFERENCE:

Letter from Jennifer Whitman (NRC) to the TSTF, "Draft Safety Evaluation of Technical Specifications Task Force Traveler TSTF-546, Revision 0,

'Revise APRM Channel Adjustment Surveillance Requirement'," dated June 20, 2017 (ADAMS Accession No. ML17163A367).

On April 21, 2016, the TSTF submitted traveler TSTF-546, Revision 0, "Revise APRM Channel Adjustment Surveillance Requirement," to the Nuclear Regulatory Commission (NRC) for review (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16112A208),). In the referenced letter, the NRC provided the draft Safety Evaluations for comment.

Attachment 1 contains a summary table providing the TSTF's comments on the draft Safety Evaluations. Attachment 2 contains a mark-up reflecting the TSTF's comments.

Should you have any questions, please contact us.

James R. Morris (PWROG/W) Lisa L. Williams (BWROG)

Otto W. Gustafson (PWROG/CE) Jordan L. Vaughan (PWROG/B&W)

Jason P. Redd (APOG) 11921 Rockville Pike, Suite 100, Rockville, MD 20852 Phone: 301-984-4400, Fax: 301-984-7600 Administration by EXCEL Services Corporation TSTF Comments on the TSTF-546 Draft Safety Evaluations TSTF Markup of Draft Safety Evaluations cc: Michelle Honcharik, Technical Specifications Branch, NRC Robert Tjader, Technical Specifications Branch, NRC Jennifer Whitman, Technical Specifications Branch, NRC

Attachment 1 TSTF Comments on the TSTF-546 Draft Safety Evaluations Page(s) Line(s)1 Comment Traveler Draft Safety Evaluation 1 28-31 This paragraph should be moved to a note in the model plant-specific safety evaluation. There is no plant-specific information to be provided in the traveler SE and brackets are not used for the described purpose in the traveler SE.

Draft Model Safety Evaluation for Plant-Specific Adoption 1 16 The bolded phrase "Month, Day, 2017 (ADAMS Accession No. MLXXXX)" should be placed in brackets, consistent with similar information in the paragraph.

1 43-46 Recommend that these paragraphs be removed. A description of generic 2 1-30 analog and digital neutron monitoring systems and various methods of stability protection are not needed or applicable to a plant-specific SE. It is not necessary to describe the plant-specific neutron monitoring system or stability protection system as the traveler SE concluded that the change is appropriate for any of the designs.

2 39-43 The existing SR language should be placed in brackets and the plant-specific SR language should be included in the issued plant-specific SE.

3 45-48 The description of the existing SR requirement should be placed in brackets.

4 12-22 It is unclear why the bracketed Note describing stability solutions is included in the model plant-specific SE. The presentation implies that the information is not to be included in an issued plant-specific SE and the information is available to the NRC reviewer in the traveler SE. We recommend that it be removed for clarity.

4 36-37 To simplify the NRC review, we recommend including bracketed example discussions of the three variations included in the TSTF-546 model application.

1 Line numbers correspond to the documents provided by the NRC and not to the attached proposed revision.

Page 3

Attachment 2 TSTF Markup of Draft Safety Evaluations

June 20, 2017 Technical Specifications Task Force 11921 Rockville Pike, Suite 100 Rockville, MD 20852

SUBJECT:

DRAFT SAFETY EVALUATION OF TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER TSTF-546, REVISION 0, "REVISE APRM CHANNEL ADJUSTMENT SURVEILLANCE REQUIREMENT" (CAC NO. MF7622)

Dear Members of the Technical Specifications Task Force:

By letter dated April 21, 2016 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16112A208), the Technical Specifications Task Force (TSTF) submitted to the U.S. Nuclear Regulatory Commission (NRC) for review and approval traveler TSTF-546, Revision 0, Revise APRM [Average Power Range Monitor] Channel Adjustment Surveillance Requirement. The NRC staffs draft safety evaluation (SE) of the traveler and a draft model SE are enclosed.

Thirty calendar days are provided to you to comment on any factual errors or clarity concerns contained in the enclosed draft SEs. The final SEs will be issued after making any necessary changes. The NRC staff's disposition of your comments on the draft SEs will be discussed in the final SEs. To facilitate the NRC staff's review of your comments, please provide a marked-up copy of the draft SEs showing proposed changes and provide a summary table of the proposed changes.

If you have any questions, please contact Michelle Honcharik at 301-415-1774 or via e-mail at Michelle.Honcharik@nrc.gov.

Sincerely, Jennifer M. Whitman, Acting Chief /RA/

Technical Specifications Branch Division of Safety Systems Office of Nuclear Reactor Regulation Project No. 753

Enclosures:

1. NRC staffs draft Safety Evaluation of the traveler

2. Draft model Safety Evaluation cc: See next page

Technical Specifications Task Force Project No. 753 cc:

Technical Specifications Task Force c/o EXCEL Services Corporation Otto W. Gustafson 11921 Rockville Pike, Suite 100 Entergy Nuclear Operations, Inc.

Rockville, MD 20852 Palisades Nuclear Power Plant Attention: Brian D. Mann 27780 Blue Star Memorial Highway E-mail: brian.mann@excelservices.com Covert, MI 49043 E-mail: ogustaf@entergy.com James R. Morris Diablo Canyon Power Plant Jordan L. Vaughan Building 104/5/21A Duke Energy P.O. Box 56 EC2ZF / P.O. Box 1006 Avila Beach, CA 93424 Charlotte, NC 28202 E-mail: james.morris@pge.com Email: jordan.vaughan@duke-energy.com Lisa L. Williams Jason P. Redd Energy Northwest Southern Nuclear Operating Company Columbia Generating Station 42 Inverness Center Parkway PO Box 968 Bin B234 Mail Drop PE20 Birmingham, AL 35242-4809 Richland, WA 99352-0968 E-mail: jpredd@southernco.com E-mail: llwilliams@energy-northwest.com

Package: Cover letter and Draft traveler SE: ML17135A188, draft Model SE: ML17135A189;

• concurrence from internal memo (ML17040A085)

• • concurred via e-mail NRR-106 OFFICE DSS/STSB DSS/EICB* DSS/SRXB** DORL/BC**

NAME MHoncharik MWaters EOesterle DWrona DATE 5/15/2017 3/9/2017 5/17/2017 5/25/2017 OFFICE OGC (NLO) DSS/STSB DSS/STSB**

NAME JWachutka MHoncharik JMWhitman (TTjader for)

DATE 6/9/17 06/20/17 06/20/17 1 DRAFT SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION 2 TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER 3 TSTF-546, REVISION 0, 4 REVISE APRM CHANNEL ADJUSTMENT SURVEILLANCE REQUIREMENT 5

6 7

1.0 INTRODUCTION

8 9 By letter dated April 21, 2016 (Agencywide Documents Access and Management System 10 (ADAMS) Accession No. ML16112A208), the Technical Specifications (TS) Task Force (TSTF) 11 submitted Traveler TSTF-546, Revise APRM [Average Power Range Monitor] Channel 12 Adjustment Surveillance Requirement [SR], Revision 0, for U.S. Nuclear Regulatory 13 Commission (NRC) review and approval. By letter dated February 2, 2017 (ADAMS Accession 14 No. ML17033A264), the TSTF submitted a response to the NRC staffs request for additional 15 information (RAI). The RAI response did not result in any changes to TSTF-546.

16 17 Traveler TSTF-546 proposes changes to the Standard Technical Specifications (STS) and 18 Bases for boiling water reactor (BWR) designs BWR/4 and BWR/6.1 The changes would be 19 incorporated into future revisions of NUREG-1433, Volumes 1 and 2, and NUREG-1434, 20 Volumes 1 and 2. NUREG-1433 is based on the BWR/4 plant design, and is representative of 21 the BWR/2, BWR/3, and, in some cases, BWR/5 designs. NUREG-1434 is based on the 22 BWR/6 plant design, and is representative of, in many cases, the BWR/5 design.

23 24 The proposed changes would revise SR 3.3.1.1.2 in NUREGs-1433 and -1434 to only require 25 adjustment of the APRM channels if the calculated power exceeds the APRM output by more 26 than 2 percent rated thermal power (RTP).

27 28 Throughout this safety evaluation (SE), items that are enclosed in square brackets signify 29 plant-specific nomenclature or values. Individual licensees would furnish site-specific 30 nomenclature or values for bracketed items when submitting a license amendment request 31 (LAR) to adopt the changes described in this SE.

32 33

2.0 REGULATORY EVALUATION

34 35 2.1 SYSTEM DESCRIPTION 36 37 The APRMs monitor neutron flux within the core to provide an indication of core power. As 38 stated in the STS Bases, the APRM channels receive input signals from the local power range 1 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Vol. 1, Specifications, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A192.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Vol. 2, Bases, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A193.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/6 Plants, NUREG-1434, Vol. 1, Specifications, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A195.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/6 Plants, NUREG-1434, Vol. 2, Bases, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A196.

Enclosure 1

1 monitors (LPRM) within the reactor core to provide an indication of the power distribution and 2 local power changes. The APRM channels average these LPRM signals to provide a 3 continuous indication of average reactor power from a few percent to greater than RTP.

4 5 The APRM system is a safety-related system with two purposes. One purpose is to monitor the 6 core thermal power level. The other purpose is to provide reactor scram and control rod block 7 signals to preserve the fuel cladding integrity. The APRM system consists of a number of 8 APRM channels that each receive input signals from LPRMs located in the reactor core. The 9 APRM channels average the LPRM inputs and because the LPRMs assigned to specific APRM 10 channels are located in diverse axial and radial locations throughout the reactor core, each 11 APRM provides a continuous indication of average reactor power. A gain adjustment can be 12 made to each ARPM channel output allowing it to be calibrated to the calculated core thermal 13 power. The typical allowable absolute difference between calculated core thermal power and 14 the APRM channel output is 2 percent.

15 16 Both analog and digital neutron monitoring systems (NMS) are installed in BWRs and have 17 different APRM system designs. Additionally, there are several different methodologies for 18 addressing BWR instability protection including: Option I-D, Option II, Enhanced Option I-19 A (E1A), Option III, and Detect and Suppress Solution-Confirmation Density (DSS-CD) and the 20 automatic backup stability protection (ABSP) for DSS-CD. The APRMs only provide input for 21 Option I-D, Option II, Enhanced Option I-A, and the ABSP for DSS-CD.

22 23 A typical analog NMS has two groups of channels with three APRM inputs to each reactor 24 protection system (RPS) trip system. Three channels per group allow one channel in each 25 group to be bypassed because any one channel trip signal in each system can cause the 26 associated trip system to be actuated. Power Range Monitor Flow Biased Simulated Thermal 27 Power - High and the APRM Fixed Neutron Flux - High functions, four channels, with two 28 channels in each trip system, are typically required to be operable by Limiting Condition for 29 Operation (LCO) 3.3.1.1 to ensure that no single instrument failure will preclude a trip of the 30 APRM system on a valid signal. If one or more required channels are inoperable, Condition A 31 requires the channel or trip system be placed in the tripped condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. If one or 32 more functions with one or more required channels are inoperable in both RPS trip systems, 33 Condition B requires that the channel(s) or trip system(s) be placed in the tripped condition 34 within six hours.

35 36 A typical digital NMS is divided into four APRM channels and four 2-out-of-4 voter channels with 37 each channel providing input to each of the four 2-out-of-4 voter channels. The four voter 38 channels are divided into two groups of two each; each group of two voter channels provides 39 input to one RPS trip system. One APRM channel is allowed to be bypassed, but no voter 40 channels are allowed to be bypassed. A trip from any one APRM channel that is not bypassed 41 will result in a "half-trip" in all four of the voter channels, but no trip inputs to either RPS trip 42 system. A trip of any two channels of APRM flow biased or neutron flux trip that are not 43 bypassed will result in a full trip in each of the four voter channels, which in turn results in two 44 trip inputs to each RPS trip system logic channel. To ensure that no single instrument failure 45 will preclude a trip on a valid signal for the APRM Flow Biased Simulated Thermal Power - High 46 and the APRM Fixed Neutron Flux - High functions, three of the four APRM channels and all 47 four voter channels are typically required to be operable by TS LCO 3.3.1.1. If one or more 48 required channels are inoperable, Condition A requires the channel be placed in the tripped 49 condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

50 51

1

2.2 PROPOSED CHANGE

S TO THE STS 2

3 The proposed changes would revise SR 3.3.1.1.2, which is associated with LCO 3.3.1.1A, 4 Reactor Protection System (RPS) Instrumentation (Without Setpoint Control Program) and 5 LCO 3.3.1.1B, Reactor Protection System (RPS) Instrumentation (With Setpoint Control 6 Program).

7 8 SR 3.3.1.1.2 currently states:

9 10 Verify the absolute difference between the average power range 11 monitor (APRM) channels and the calculated power is < 2% RTP 12 [plus any gain adjustment required by LCO 3.2.4, Average Power 13 Range Monitor (APRM) Setpoints] while operating at > 25% RTP 14 15 The proposed SR 3.3.1.1.2 would state:

16 17 Compare the average power range monitor (APRM) channels to 18 the calculated power. Adjust the APRM channels if the calculated 19 power exceeds the APRM output by more than 2% RTP while 20 operating at 25% RTP 21 22 Corresponding changes are proposed to the STS Bases. A summary of the revised STS Bases 23 and the NRC staffs evaluation of the revised Bases are provided in an attachment to this SE.

24 25 2.3 APPLICABLE REGULATORY REQUIREMENTS AND GUIDANCE 26 27 Section IV, The Commission Policy, of the Final Policy Statement on Technical Specifications 28 Improvements for Nuclear Power Reactors (58 Federal Register 39132), dated July 22, 1993, 29 states in part:

30 31 The purpose of Technical Specifications is to impose those 32 conditions or limitations upon reactor operation necessary to 33 obviate the possibility of an abnormal situation or event giving rise 34 to an immediate threat to the public health and safety by 35 identifying those features that are of controlling importance to 36 safety and establishing on them certain conditions of operation 37 which cannot be changed without prior Commission approval.

38 39 [T]he Commission will also entertain requests to adopt portions 40 of the improved STS [(e.g., TSTF-546)], even if the licensee does 41 not adopt all STS improvements.

42 43 The Commission encourages all licensees who submit 44 Technical Specification related submittals based on this Policy 45 Statement to emphasize human factors principles.

46 47 In accordance with this Policy Statement, improved STS have 48 been developed and will be maintained for [BWR designs]. The 49 Commission encourages licensees to use the improved STS as 50 the basis for plant-specific Technical Specifications.

1 [I]t is the Commission intent that the wording and Bases of the 2 improved STS be used to the extent practicable.

3 4 As described in the Commissions Final Policy Statement on Technical Specifications 5 Improvements for Nuclear Power Reactors, recommendations were made by NRC and industry 6 task groups for new STS that include greater emphasis on human factors principles in order to 7 add clarity and understanding to the text of the STS, and provide improvements to the Bases of 8 STS, which provides the purpose for each requirement in the specification. Improved vendor-9 specific STS were developed and issued by the NRC in September 1992.

10 11 The regulation at Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) 12 requires an applicant for an operating license to include in the application proposed TS in 13 accordance with the requirements of 10 CFR 50.36. The applicant must include in the 14 application a summary statement of the bases or reasons for such specifications, other than 15 those covering administrative controls. However, per 10 CFR 50.36(a)(1), these technical 16 specification bases shall not become part of the technical specifications.

17 18 Additionally, 10 CFR 50.36(b) requires:

19 20 Each license authorizing operation of a utilization facility will 21 include technical specifications. The technical specifications will 22 be derived from the analyses and evaluation included in the safety 23 analysis report, and amendments thereto, submitted pursuant to 24 [10 CFR] 50.34 [Contents of applications; technical information].

25 The Commission may include such additional technical 26 specifications as the Commission finds appropriate.

27 28 The categories of items required to be in the TSs are provided in 10 CFR 50.36(c). As required 29 by 10 CFR 50.36(c)(2)(i), the TSs will include LCOs, which are the lowest functional capability 30 or performance levels of equipment required for safe operation of the facility. Per 10 CFR 31 50.36(c)(2)(i), when an LCO of a nuclear reactor is not met, the licensee shall shut down the 32 reactor or follow any remedial action permitted by the TSs until the condition can be met.

33 34 The regulation at 10 CFR 50.36(c)(3) requires TSs to include items in the category of SRs, 35 which are requirements relating to test, calibration, or inspection to assure that the necessary 36 quality of systems and components is maintained, that facility operation will be within safety 37 limits, and that the LCOs will be met.

38 39 Per 10 CFR 50.90, whenever a holder of a license desires to amend the license, application for 40 an amendment must be filed with the Commission, fully describing the changes desired, and 41 following as far as applicable, the form prescribed for original applications.

42 43 Per 10 CFR 50.92(a), in determining whether an amendment to a license will be issued to the 44 applicant, the Commission will be guided by the considerations which govern the issuance of 45 initial licenses to the extent applicable and appropriate.

46 47 The NRC staffs guidance for the review of TSs is in Chapter 16, Technical Specifications, of 48 NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for 49 Nuclear Power Plants (SRP), dated March 2010 (ADAMS Accession No. ML100351425). As 50 described therein, as part of the regulatory standardization effort, the NRC staff has prepared 51 STS for each of the light-water reactor nuclear designs.

1

3.0 TECHNICAL EVALUATION

2 3 The existing TS SR 3.3.1.1.2 requires verification that the absolute difference between the 4 APRM channels and the calculated power is 2 percent RTP [plus any gain adjustment 5 required by LCO 3.2.4, Average Power Range Monitor (APRM) Setpoints] while operating at 6 > 25 percent RTP. If the absolute difference is greater than 2 percent, the APRM channel is 7 declared inoperable. An acceptable way to restore operability is to adjust the gain for the APRM 8 channel to restore the absolute difference to 2 percent. If the APRM channel is reading higher 9 than the calculated thermal power, this adjustment would be non-conservative with respect to 10 the RPS trip setpoint. If the APRM channel is reading lower than the calculated thermal power, 11 this adjustment would be conservative with respect to the RPS trip setpoint.

12 13 The proposed change would require adjustment of the APRM channel only if the APRM is 14 non-conservative with respect to calculated thermal power (i.e., reading lower than calculated 15 thermal power). In this situation, the adjustment of the APRM channel is permitted, but not 16 required, if the APRM channel is conservative with respect to the calculated thermal power.

17 18 The NRC staff requested additional information on whether this proposed change would affect 19 the effectiveness of any of the stability solutions for BWRs. In the response dated February 2, 20 2017, the TSTF stated that stability solutions (e.g., Option III and DSS-CD) that rely on the 21 LPRMs are not affected by this change. For stability solutions that rely on the APRMs for the 22 main licensing basis protection (e.g., Option I-D, Option II, Enhanced Option I-A, and the ABSP 23 for DSS-CD), this change would result in earlier (i.e., conservative) RPS actuation. The NRC 24 staff reviewed this response and determined that it is not clear that a high APRM signal is 25 always conservative for the ABSP. However, this backup solution is only used when the normal 26 stability protection is inoperable and its use is limited to 120 days. Therefore, the proposed 27 change would negligibly affect the ABSP and is acceptable to the NRC staff.

28 29 The regulation at 10 CFR 50.36(c)(3) requires that the TS contain SRs, which are requirements 30 relating to test, calibration, or inspection to assure that the necessary quality of systems and 31 components is maintained, that facility operation will be within safety limits, and that the limiting 32 conditions for operation will be met. The NRC staff reviewed the changes proposed to SR 33 3.3.1.1.2 as described in this SE. The NRC staff determined that the SR, as modified, 34 continues to provide appropriate controls and acceptance criteria for adjustment of the APRMs 35 to ensure that the APRMs appropriately reflect actual reactor power. The NRC staff determined 36 that the SR continues to verify the operability of the APRMs and provide assurance that the 37 necessary quality of systems and components is maintained.

38 39

4.0 CONCLUSION

40 41 The NRC staff reviewed traveler TSTF-546, Revision 0, which proposed changes to 42 NUREG-1433, Volumes 1 (STS) and 2 (Bases), and NUREG-1434, Volumes 1 (STS) and 43 2 (Bases). The NRC staff determined that the proposed changes to the STS meet the 44 standards for TS in 10 CFR 50.36(b). The proposed changes to the SR assure that the 45 necessary quality of systems and components is maintained, that facility operation will be within 46 safety limits, and that the LCOs will be met, and satisfy 10 CFR 50.36(c)(3). Additionally, the 47 changes to the STS were reviewed for technical clarity and consistency with customary 48 terminology and format in accordance with SRP Chapter 16.

49 50 The proposed Bases, which will be added to future revisions to NUREG-1433, Volume 2, and 51 NUREG-1434, Volume 2, satisfy the Commissions Policy Statement by addressing the

1 questions specified in the policy statement, and cite references to appropriate licensing 2 documentation to support the Bases.

3 4 Technical contacts: Jennifer M. Whitman, NRR/DSS/SRXB 5 Gursharan Singh, NRR/DE/EICB 6

7

Attachment:

Basis for Accepting the Proposed Changes to the Standard Technical 8 Specification Bases, Volume 2 of NUREGs-1433 and -1434 9

10 Date: June 20, 2017 11 12 13 14

1 ATTACHMENT 2

3 BASIS FOR ACCEPTING THE PROPOSED CHANGES TO THE STANDARD TECHNICAL 4 SPECIFICATION BASES, VOLUME 2 OF NUREGS-1433 AND -1434 5

6 7

1.0 INTRODUCTION

8 9 Traveler Technical Specifications (TS) Task Force (TSTF) TSTF-546, Revise APRM [Average 10 Power Range Monitor] Channel Adjustment Surveillance Requirement [SR], Revision 0, 11 proposes changes to the Standard Technical Specifications (STS) and Bases for boiling water 12 reactor (BWR) designs BWR/4 and BWR/6.2 The changes would be incorporated into future 13 revisions of NUREG-1433, Volumes 1 and 2, and NUREG-1434, Volumes 1 and 2.

14 NUREG-1433 is based on the BWR/4 plant design, and is representative of the BWR/2, BWR/3, 15 and, in some cases, BWR/5 designs. NUREG-1434 is based on the BWR/6 plant design, and is 16 representative of, in many cases, the BWR/5 design.

17 18 The proposed changes would revise SR 3.3.1.1.2 in NUREGs-1433 and -1434 to only require 19 adjustment of the APRM channels if the calculated power exceeds the APRM output by more 20 than 2 percent rated thermal power (RTP). The Bases for SR 3.3.1.1.2 in NUREGs-1433 and -

21 1434 would also be revised. A summary of the revised Bases and the U.S. Nuclear Regulatory 22 Commission (NRC) staffs evaluation of the revised Bases are presented in this attachment.

23 24

2.0 REGULATORY EVALUATION

25 26 2.1 Applicable Regulations and Guidance 27 28 The regulation at Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) 29 states that each applicant for a license authorizing operation of a production or utilization facility 30 shall include in his application proposed technical specifications in accordance with the 31 requirements of this section. A summary statement of the bases or reasons for such 32 specifications, other than those covering administrative controls, shall also be included in the 33 application, but shall not become part of the technical specifications.

34 35 In its Final Policy Statement on Technical Specifications Improvements for Nuclear Power 36 Reactors, dated July 22, 1993 (58 Federal Register 39132), the Commission presented its 37 policy on the scope and purpose of the TS. The Commission explained how implementation of 38 the policy statement through implementation of the improved STS is expected to produce an 39 improvement in the safety of nuclear power plants through the use of more operator-oriented 2 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Vol. 1, Specifications, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A192.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Vol. 2, Bases, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A193.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/6 Plants, NUREG-1434, Vol. 1, Specifications, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A195.

U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/6 Plants, NUREG-1434, Vol. 2, Bases, Rev. 4.0, April 2012, ADAMS Accession No. ML12104A196.

1 TS, improved TS Bases, reduced action-statement-induced plant transients, and more efficient 2 use of NRC and industry resources.

3 4 The Final Policy Statement provides the following description of the scope and the purpose of 5 the Technical Specification Bases:

6 7 Appropriate Surveillance Requirements and Actions should be 8 retained for each LCO [limiting condition for operation] which 9 remains or is included in the Technical Specifications. Each LCO, 10 Action, and Surveillance Requirement should have supporting 11 Bases. The Bases should at a minimum address the following 12 questions and cite references to appropriate licensing 13 documentation (e.g., FSAR, Topical Report) to support the Bases.

14 15 1. What is the justification for the Technical Specification, i.e., which 16 Policy Statement criterion requires it to be in the Technical 17 Specifications?

18 19 2. What are the Bases for each LCO, i.e., why was it determined to 20 be the lowest functional capability or performance level for the 21 system or component in question necessary for safe operation of 22 the facility and, what are the reasons for the Applicability of the 23 LCO?

24 25 3. What are the Bases for each Action, i.e., why should this remedial 26 action be taken if the associated LCO cannot be met; how does 27 this Action relate to other Actions associated with the LCO; and 28 what justifies continued operation of the system or component at 29 the reduced state from the state specified in the LCO for the 30 allowed time period?

31 32 4. What are the Bases for each Safety Limit?

33 34 5. What are the Bases for each Surveillance Requirement and 35 Surveillance Frequency; i.e., what specific functional requirement 36 is the surveillance designed to verify? Why is this surveillance 37 necessary at the specified frequency to assure that the system or 38 component function is maintained, that facility operation will be 39 within the Safety Limits, and that the LCO will be met?

40 41 Note: In answering these questions the Bases for each number 42 (e.g., Allowable Value, Response Time, Completion Time, 43 Surveillance Frequency), state, condition, and definition (e.g.,

44 operability) should be clearly specified. As an example, a number 45 might be based on engineering judgment, past experience, or 46 PSA [probabilistic safety assessment] insights; but this should be 47 clearly stated.

48 49 The NRC staff used the guidance contained in the Final Policy Statement during its evaluation 50 of the proposed changes to the Bases.

51

1 2.2 Description of Changes 2

3 Volumes 2 of NUREGs-1433 and -1434 contain the Bases for each Safety Limit and each LCO 4 contained in Volumes 1 of NUREGs-1433 and -1434. The Bases for each LCO are organized 5 into the following sections:

6 7 Background; 8 Applicable Safety Analyses, LCO, and Applicability; 9 Actions; 10 Surveillance Requirements; and 11 References.

12 13 The Bases for SR 3.3.1.1.2 in NUREGs-1433 and -1434 are proposed to be revised. The 14 following discussion provides a summary of the revised Bases, followed by the NRC staffs 15 evaluation of the revised Bases.

16 17

3.0 TECHNICAL EVALUATION

18 19 The Bases for SR 3.3.1.1.2 are proposed to be revised by the insertion of a description of the 20 revised SR 3.3.1.1.2. The revised Bases state that the APRMs are adjusted to the reactor 21 power calculated from a heat balance if the heat balance calculated reactor power exceeds the 22 APRM channel output by more than 2 percent RTP. The Bases explain that, if the APRM 23 channel cannot be adjusted to within this tolerance, the channel is declared inoperable. The 24 revised SR 3.3.1.1.2 does not preclude adjusting the APRMs if the reactor power is less than 25 the APRM indication, but this adjustment is not required for APRM operability.

26 27 The NRC staff reviewed the revised Bases and determined that they adequately provide an 28 appropriate description of the SR, the conditions under which an APRM channel is considered 29 inoperable, and the basis for the SR.

30 31

4.0 CONCLUSION

32 33 The NRC staff determined that the proposed TS Bases changes are consistent with the 34 proposed TS changes and provide an explanation and supporting information for the SR.

35 Therefore, the NRC staff determined that the revised Bases are consistent with the 36 Commission's Final Policy Statement on Technical Specifications Improvements for Nuclear 37 Power Reactors, dated July 22, 1993 (58 Federal Register 39132).

1 DRAFT MODEL SAFETY EVALUATION 2 BY THE OFFICE OF NUCLEAR REACTOR REGULATION 3 TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER 4 TSTF-546, REVISION 0, 5 REVISE APRM CHANNEL ADJUSTMENT SURVEILLANCE REQUIREMENT 6

7 [NOTE: Throughout this safety evaluation (SE), items that are enclosed in square brackets 8 signify plant-specific nomenclature or values to be taken from the licensee's submittal.]

9 10

1.0 INTRODUCTION

11 12 By application dated [enter date] (Agencywide Documents Access and Management System 13 (ADAMS) Accession No. [MLXXXXXXXXX]), [name of licensee] (the licensee) requested 14 changes to the technical specifications (TSs) for [name of facility]. Specifically, the licensee 15 requested changes to the TSs to adopt Technical Specifications Task Force (TSTF) traveler 16 TSTF-546, Revision 0, Revise APRM [Average Power Range Monitor] Channel Adjustment 17 Surveillance Requirement, dated April 21, 2016 (ADAMS Accession No. ML16112A208). The 18 NRC approved the traveler on [Month, Day, 2017 (ADAMS Accession No. MLXXXX)].

19 20 The proposed changes would revise a surveillance requirement (SR) to only require adjustment 21 of the APRM channels if the calculated power exceeds the APRM output by more than 22 2 percent rated thermal power (RTP).

23 24

2.0 REGULATORY EVALUATION

25 26 2.1 SYSTEM DESCRIPTION 27 28 The APRMs monitor neutron flux within the core to provide an indication of core power. The 29 APRM channels receive input signals from the local power range monitors (LPRM) within the 30 reactor core to provide an indication of the power distribution and local power changes. The 31 APRM channels average these LPRM signals to provide a continuous indication of average 32 reactor power from a few percent to greater than RTP.

33 34 The APRM system is a safety-related system with two purposes. One purpose is to monitor the 35 core thermal power level. The other purpose is to provide reactor scram and control rod block 36 signals to preserve the fuel cladding integrity. The APRM system consists of a number of 37 APRM channels that each receive input signals from LPRMs located in the reactor core. The 38 APRM channels average the LPRM inputs and because the LPRMs assigned to specific APRM 39 channels are located in diverse axial and radial locations throughout the reactor core, each 40 APRM provides a continuous indication of average reactor power. A gain adjustment can be 41 made to each ARPM channel output allowing it to be calibrated to the calculated core thermal 42 power. The typical allowable absolute difference between calculated core thermal power and 43 the APRM channel output is 2 percent.

44 45 Both analog and digital neutron monitoring systems (NMS) are installed in BWRs and have 46 different APRM system designs. Additionally, there are several different methodologies for Enclosure 2

1 addressing BWR instability protection including: Option I-D, Option II, Enhanced 2 Option I-A (E1A), Option III, and Detect and Suppress Solution-Confirmation Density (DSS-CD) 3 and the automatic backup stability protection (ABSP) for DSS-CD. The APRMs only provide 4 input for Option I-D, Option II, Enhanced Option I-A, and the ABSP for DSS-CD.

5 6 A typical analog NMS has two groups of channels with three APRM inputs to each reactor 7 protection system (RPS) trip system. Three channels per group allow one channel in each 8 group to be bypassed because any one channel trip signal in each system can cause the 9 associated trip system to be actuated. Power Range Monitor Flow Biased Simulated Thermal 10 Power - High and the APRM Fixed Neutron Flux - High functions, four channels, with two 11 channels in each trip system, are typically required to be operable by Limiting Condition for 12 Operation (LCO) 3.3.1.1 to ensure that no single instrument failure will preclude a trip of the 13 APRM system on a valid signal. If one or more required channels are inoperable, Condition A 14 requires the channel or trip system be placed in the tripped condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. If one or 15 more functions with one or more required channels are inoperable in both RPS trip systems, 16 Condition B requires that the channel(s) or trip system(s) be placed in the tripped condition 17 within six hours.

18 19 A typical digital NMS is divided into four APRM channels and four 2-out-of-4 voter channels with 20 each channel providing input to each of the four 2-out-of-4 voter channels. The four voter 21 channels are divided into two groups of two each; each group of two voter channels provides 22 input to one RPS trip system. One APRM channel is allowed to be bypassed, but no voter 23 channels are allowed to be bypassed. A trip from any one APRM channel that is not bypassed 24 will result in a half-trip in all four of the voter channels, but no trip inputs to either RPS trip 25 system. A trip of any two channels of APRM flow biased or neutron flux trip that are not 26 bypassed will result in a full trip in each of the four voter channels, which in turn results in two 27 trip inputs to each RPS trip system logic channel. To ensure that no single instrument failure 28 will preclude a trip on a valid signal for the APRM Flow Biased Simulated Thermal Power - High 29 and the APRM Fixed Neutron Flux - High functions, three of the four APRM channels and all 30 four voter channels are typically required to be operable by TS LCO 3.3.1.1. If one or more 31 required channels are inoperable, Condition A requires the channel be placed in the tripped 32 condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

33 34 2.2 PROPOSED TECHNICAL SPECIFICATION CHANGES 35 36 The proposed changes would revise SR 3.3.1.1.2, which is associated with LCO 3.3.1.1, 37 Reactor Protection System (RPS) Instrumentation.

38 39 SR 3.3.1.1.2 currently states:

40 41 [Verify the absolute difference between the average power range 42 monitor (APRM) channels and the calculated power is 2% RTP 43 [plus any gain adjustment required by LCO 3.2.4, Average Power 44 Range Monitor (APRM) Setpoints] while operating at 25% RTP ]

45

1 The proposed SR 3.3.1.1.2 would state:

2 3 Compare the average power range monitor (APRM) channels to 4 the calculated power. Adjust the APRM channels if the calculated 5 power exceeds the APRM output by more than 2% RTP while 6 operating at 25% RTP 7

8 2.3 REGULATORY REQUIREMENTS AND GUIDANCE 9

10 The regulation at Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) 11 requires an applicant for an operating license to include in the application proposed TS in 12 accordance with the requirements of 10 CFR 50.36. The applicant must include in the 13 application a summary statement of the bases or reasons for such specifications, other than 14 those covering administrative controls.... However, per 10 CFR 50.36(a)(1), these technical 15 specification bases shall not become part of the technical specifications.

16 17 Additionally, 10 CFR 50.36(b) requires:

18 19 Each license authorizing operation of a utilization facility will 20 include technical specifications. The technical specifications will 21 be derived from the analyses and evaluation included in the safety 22 analysis report, and amendments thereto, submitted pursuant to 23 [10 CFR] 50.34 [Contents of applications; technical information].

24 The Commission may include such additional technical 25 specifications as the Commission finds appropriate.

26 27 The categories of items required to be in the TSs are provided in 10 CFR 50.36(c). As required 28 by 10 CFR 50.36(c)(2)(i), the TSs will include limiting conditions for operation (LCOs), which are 29 the lowest functional capability or performance levels of equipment required for safe operation 30 of the facility. Per 10 CFR 50.36(c)(2)(i), when an LCO of a nuclear reactor is not met, the 31 licensee shall shut down the reactor or follow any remedial action permitted by the TSs until the 32 condition can be met.

33 34 The regulation at 10 CFR 50.36(c)(3) requires TSs to include items in the category of SRs, 35 which are requirements relating to test, calibration, or inspection to assure that the necessary 36 quality of systems and components is maintained, that facility operation will be within safety 37 limits, and that the LCOs will be met.

38 39 The NRC staffs guidance for the review of TSs is in Chapter 16, Technical Specifications, of 40 NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for 41 Nuclear Power Plants (SRP), dated March 2010 (ADAMS Accession No. ML100351425).

42 43

3.0 TECHNICAL EVALUATION

44 45 The existing TS SR 3.3.1.1.2 requires [verification that the absolute difference between the 46 APRM channels and the calculated power is 2 percent RTP [plus any gain adjustment 47 required by LCO 3.2.4, Average Power Range Monitor (APRM) Setpoints] while operating at 48 25 percent RTP.] If the absolute difference is greater than 2 percent, the APRM channel is

1 declared inoperable. An acceptable way to restore operability is to adjust the gain for the APRM 2 channel to restore the absolute difference to 2 percent. If the APRM channel is reading higher 3 than the calculated thermal power, this adjustment would be non-conservative with respect to 4 the RPS trip setpoint. If the APRM channel is reading lower than the calculated thermal power, 5 this adjustment would be conservative with respect to the RPS trip setpoint.

6 7 The proposed change would require adjustment of the APRM channel only if the APRM is 8 non-conservative with respect to calculated thermal power (i.e., reading lower than calculated 9 thermal power). In this situation, the adjustment of the APRM channel is permitted, but not 10 required, if the APRM channel is conservative with respect to the calculated thermal power.

11 12 [NOTE: During the review of the traveler, the NRC staff requested additional information on 13 whether this proposed change would affect the effectiveness of any of the stability solutions for 14 BWRs. In the response dated February 2, 2017, the TSTF stated that stability solutions (e.g.,

15 Option III and DSS-CD) that rely on the LPRMs are not affected by this change. For stability 16 solutions that rely on the APRMs for the main licensing basis protection (e.g., Option I-D, Option 17 II, Enhanced Option I-A, and the ABSP for DSS-CD), this change would result in earlier (i.e.,

18 conservative) RPS actuation. The NRC staff reviewed this response and determined that it is 19 not clear that a high APRM signal is always conservative for the ABSP. However, this backup 20 solution is only used when the normal stability protection is inoperable and its use is limited to 21 120 days. Therefore, the proposed change would negligibly affect the ABSP and is acceptable 22 to the NRC staff.]

23 24 The regulation at 10 CFR 50.36(c)(3) requires that the TSs contain SRs, which are 25 requirements relating to test, calibration, or inspection to assure that the necessary quality of 26 systems and components is maintained, that facility operation will be within safety limits, and 27 that the limiting conditions for operation will be met. The NRC staff reviewed the changes 28 proposed to SR 3.3.1.1.2 as described in this SE. The NRC staff determined that the SR, as 29 modified, continues to provide appropriate controls and acceptance criteria for adjustment of the 30 APRMs to ensure that the APRMs appropriately reflect actual reactor power. The NRC staff 31 determined that the SR continues to verify the operability of the APRMs and provide assurance 32 that the necessary quality of systems and components is maintained.

33 34 3.1 VARIATIONS FROM THE APPROVED TRAVELER 35 36 [NOTE: Technical reviewers and/or project manager to discuss variations from the approved 37 traveler and whether they are acceptable. Choose the applicable paragraphs based on 38 information provided in the LAR.]

39 40 [The licensee is not proposing any variations from the TS changes described in TSTF-546 or 41 the applicable parts of the NRC staffs safety evaluation of TSTF-546.]

42 43 [The licensee is proposing the following variations from the TS changes described in TSTF-546 44 or the applicable parts of TSTF-546 or the NRC staffs safety evaluation. These variations do 45 not affect the applicability of TSTF-546 or the NRC staff's safety evaluation to the proposed 46 license amendment.]

47 48 [The [PLANT] TS utilize different [numbering][and][titles] than the Standard Technical 49 Specifications on which TSTF-546 was based. Specifically, [describe differences between the

1 plant-specific TS numbering and/or titles and the TSTF-546 numbering and titles.] These 2 differences are administrative and do not affect the applicability of TSTF-546 to the [PLANT]

3 TS.]

4 5 [The Traveler discusses the applicable regulatory requirements and guidance, including the 6 10 CFR 50, Appendix A, General Design Criteria (GDC). [PLANT] was not licensed to the 7 10 CFR 50, Appendix A, GDC. The [PLANT] equivalents of the referenced GDC are [discussion 8 from licensee's application.] These differences do not alter the conclusion that the proposed 9 change is applicable to [PLANT].]

10 11

3.2 CONCLUSION

12 13 The NRC staff reviewed the proposed changes to the TSs, and determined that they meet the 14 standards for TSs in 10 CFR 50.36(b). The proposed changes to the SR assure that the 15 necessary quality of systems and components is maintained, that facility operation will be within 16 safety limits, and that the LCOs will be met, and satisfy 10 CFR 50.36(c)(3). Additionally, the 17 changes to the TSs were reviewed for technical clarity and consistency with customary 18 terminology and format in accordance with SRP Chapter 16.

19 20

4.0 STATE CONSULTATION

21 22 [Note: This section is to be prepared by the PM.]

23 24 In accordance with the Commission's regulations, the [Name of State] State official was notified 25 of the proposed issuance of the amendment on [enter date]. The State official had [no]

26 comments. [If comments were provided, they should be addressed here].

27 28

5.0 ENVIRONMENTAL CONSIDERATION

29 30 [Note: This section is to be prepared by the PM. As needed, the PM should coordinate with 31 NRRs Environmental Review and Projects Branch (RERP) to determine the need for an EA.

32 Specific guidance on preparing EAs and considering environmental issues is contained in NRR 33 Office Instruction LIC-203, Procedural Guidance for Preparing Categorical Exclusions, 34 Environmental Assessments, and Considering Environmental Issues.]

35 36 The amendment changes a requirement with respect to the installation or use of facility 37 components located within the restricted area as defined in 10 CFR Part 20 or changes to SRs.

38 The NRC staff has determined that the amendment involves no significant increase in the 39 amounts, and no significant change in the types, of any effluents that may be released offsite, 40 and that there is no significant increase in individual or cumulative occupational radiation 41 exposure. The Commission has previously issued a proposed finding that the amendment 42 involves no significant hazards consideration, and there has been no public comment on such 43 finding [(XX FR XXX)]. Accordingly, the amendment meets the eligibility criteria for categorical 44 exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental 45 impact statement or environmental assessment need be prepared in connection with the 46 issuance of the amendment.

47 48

6.0 CONCLUSION

49

1 The Commission has concluded, based on the considerations discussed above, that (1) there is 2 reasonable assurance that the health and safety of the public will not be endangered by 3 operation in the proposed manner, (2) there is reasonable assurance that such activities will be 4 conducted in compliance with the Commission's regulations, and (3) the issuance of the 5 amendment will not be inimical to the common defense and security or to the health and safety 6 of the public.

7 7.08 REFERENCES 9

10 Optional section to be prepared by the PM and technical reviewers. If document is publicly 11 available, the ADAMS Accession No. should be listed.

12 13 [NOTE: Replace principal contributor names with the individual(s) who prepare the plant-specific 14 SE.]

15 Principal Contributors: Jennifer M. Whitman, NRR/DSS/SRXB 16 Gursharan Singh, NRR/DE/EICB 17 18 Date: June 20, 2017 19