ML18226A318
| ML18226A318 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force |
| Issue date: | 09/20/2018 |
| From: | Victor Cusumano NRC/NRR/DSS/STSB |
| To: | |
| Honcharik M, NRR/DSS, 301-415-1774 | |
| Shared Package | |
| ML18226A327 | List: |
| References | |
| CAC MF9955, EPID L-2017-PMP-0006 | |
| Download: ML18226A318 (11) | |
Text
Enclosure 2 General Directions: This Model SE provides the format and content to be used when preparing 1
the plant specific SE of an LAR to adopt TSTF 563, Revision 0. The bolded bracketed 2
information shows text that should be filled in for the specific amendment; individual licensees 3
would furnish site-specific nomenclature or values for these bracketed items. The italicized 4
wording provides guidance on what should be included in each section and should not be 5
included in the SE.
6 7
DRAFT MODEL SAFETY EVALUATION 8
BY THE OFFICE OF NUCLEAR REACTOR REGULATION 9
TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER 10 TSTF-563, REVISION 0 11 REVISE INSTRUMENT TESTING DEFINITIONS TO INCORPORATE THE SURVEILLANCE 12 FREQUENCY CONTROL PROGRAM 13 USING THE CONSOLIDATED LINE ITEM IMPROVEMENT PROCESS 14 (CAC NO. MF9955, EPID L-2017-PMP-0006) 15 16 17
1.0 INTRODUCTION
18 19 By application dated [enter date] (Agencywide Documents Access and Management System 20 (ADAMS) Accession No. [MLXXXXXXXXX]), [as supplemented by letter(s) dated [enter 21 date(s))), [name of licensee] (the licensee) submitted a license amendment request (LAR) for 22
[name of facility (abbreviated name), applicable units].
23 24 The amendment would revise the current instrumentation testing definitions of Channel 25 Calibration(( and Channel Functional Test] OR [, Channel Operational Test (COT), and Trip 26 Actuation Device Operational Test (TADOT))) to permit determination of the appropriate 27 frequency to perform the Surveillance Requirement (SR) based on the devices being tested in 28 each step. The proposed changes are based on Technical Specifications Task Force (TSTF) 29 Traveler TSTF-563, Revision 0, Revise Instrument Testing Definitions to Incorporate the 30 Surveillance Frequency Control Program, dated May 10, 2017 (ADAMS Accession 31 No. ML17130A819). The U.S. Nuclear Regulatory Commission (NRC or the Commission) 32 issued a final safety evaluation (SE) approving TSTF-563, Revision 0, on [enter date] (ADAMS 33 Accession No. [MLXXXXXXXXX]).
34 35
{NOTE: TSTF-563 is only applicable to plants that have already adopted TSTF-425 or have an 36 approved SFCP that uses NEI 04-10.}
37 38 An SFCP was incorporated into the [PLANT] TS in a license amendment dated [enter date]
39 (ADAMS Accession No. [MLXXXXXXXXX]).
40 41
((The licensee has proposed variations from the TS changes described in TSTF-563. The 42 variations are described in Section 2.2.1 of this SE and evaluated in Section 3.1.] OR [The 43 licensee is not proposing any variations from the TS changes described in TSTF-563 or 44 the applicable parts of the NRC staffs SE of TSTF-563.))
45 46
[The supplemental letters dated [enter date(s)], provided additional information that 1
clarified the application, did not expand the scope of the application as originally 2
noticed, and did not change the NRC staffs original proposed no significant hazards 3
consideration determination as published in the Federal Register on [enter date] (cite FR 4
reference).]
5 6
2.0 REGULATORY EVALUATION
7 8
2.1 DESCRIPTION
OF SURVEILLANCE FREQUENCY CONTROL PROGRAM AND 9
INSTRUMENT TESTING 10 11 The technical specifications (TSs) require the surveillances for instrumentation channels to be 12 performed within the specified frequency, using any series of sequential, overlapping, or total 13 channel steps. TSTF-425, Revision 3, Relocate Surveillance Frequencies to Licensee 14 Control - RITSTF [Risk-Informed TSTF] Initiative 5b, revised the TSs to relocate all periodic 15 surveillance frequencies to licensee control. Changes to the relocated surveillance frequencies 16 are made in accordance with the TS program referred to as the Surveillance Frequency Control 17 Program (SFCP). The SFCP allows a new surveillance frequency to be determined for the 18 channel, but that frequency must consider all components in the channel and applies to the 19 entire channel.
20 21 A typical instrument channel consists of many different components, such as sensors, rack 22 modules, and indicators. These components have different short-term and long-term 23 performance (drift) characteristics, resulting in the potential for different calibration frequency 24 requirements. Under the current TSs, the most limiting component calibration frequency for the 25 channel must be chosen when a revised frequency is considered under the SFCP. As a result, 26 all components that makeup a channel must be calibrated at a frequency equal to the channel 27 component with the shortest (i.e., most frequent) surveillance frequency.
28 29 Some channel components, such as pressure transmitters, are very stable with respect to drift 30 and could support a substantially longer calibration frequency than the other components in the 31 channel. Currently, the SRs in many plants are performed in steps (e.g., a pressure sensor or 32 transmitter is calibrated during a refueling outage and the rack signal conditioning modules are 33 calibrated while operating at power). The proposed change extends this concept to permit the 34 surveillance frequency of each step to be determined under the SFCP based on the 35 component(s) surveilled in the step instead of all components in the channel. This will allow 36 each component to be tested at the appropriate frequency based on the components long-term 37 performance characteristics.
38 39 Allowing an appropriate surveillance frequency for performing a channel calibration on each 40 component or group of components could reduce radiation dose associated with inplace 41 calibration of sensors, reduce wear on equipment, reduce unnecessary burden on plant staff, 42 and reduce opportunities for calibration errors.
43 44
2.2 PROPOSED CHANGE
S TO THE TECHNICAL SPECIFICATIONS 45 46 Currently, the Channel Calibration(( and Channel Functional Test] OR [, COT, and TADOT))
47 may be performed by any series of sequential, overlapping or total channel steps. The 48 proposed changes to the TSs would revise the definitions of Channel Calibration(( and Channel 49 Functional Test] OR [, COT, and TADOT)) to indicate that the step must be performed within 50 the most limiting frequency for the components included in that step by adding the words, and 1
each step must be performed within the Frequency in the Surveillance Frequency Control 2
Program for the devices included in the step at the end of the last sentence of each definition.
3 4
The following paragraph denotes the changes to the Channel Calibration definition. Changes 5
are shown in italics:
6 7
{NOTE: For B&W, CE, and GE plant designs use this paragraph.}
8 9
[A CHANNEL CALIBRATION shall be the adjustment, as necessary, of the 10 channel output such that it responds within the necessary range and 11 accuracy to known values of the parameter that the channel monitors. The 12 CHANNEL CALIBRATION shall encompass all devices in the channel 13 required for channel OPERABILITY and the CHANNEL FUNCTIONAL TEST.
14 Calibration of instrument channels with resistance temperature detector 15 (RTD) or thermocouple sensors may consist of an inplace qualitative 16 assessment of sensor behavior and normal calibration of the remaining 17 adjustable devices in the channel. The CHANNEL CALIBRATION may be 18 performed by means of any series of sequential, overlapping, or total 19 channel steps, and each step must be performed within the Frequency in 20 the Surveillance Frequency Control Program for the devices included in the 21 step.]
22 23
{NOTE: For Westinghouse plant designs use this paragraph.}
24 25
[A CHANNEL CALIBRATION shall be the adjustment, as necessary, of the 26 channel output such that it responds within the necessary range and 27 accuracy to known values of the parameter that the channel monitors. The 28 CHANNEL CALIBRATION shall encompass all devices in the channel 29 required for channel OPERABILITY. Calibration of instrument channels 30 with resistance temperature detector (RTD) or thermocouple sensors may 31 consist of an inplace qualitative assessment of sensor behavior and 32 normal calibration of the remaining adjustable devices in the channel. The 33 CHANNEL CALIBRATION may be performed by means of any series of 34 sequential, overlapping, or total channel steps, and each step must be 35 performed within the Frequency in the Surveillance Frequency Control 36 Program for the devices included in the step.]
37 38
{NOTE: For B&W, CE, and GE plant designs use this paragraph.}
39 40
[The following paragraph denotes the changes to the Channel Functional Test definition.
41 Changes are shown in italics:
42 43
...The CHANNEL FUNCTIONAL TEST may be performed by means of any 44 series of sequential, overlapping, or total [channel] steps, and each step 45 must be performed within the Frequency in the Surveillance Frequency 46 Control Program for the devices included in the step.]
47 48
{NOTE: For Westinghouse plant designs use this paragraph.}
49 50
[The following paragraphs denote the changes to the COT and TADOT definitions.
1 Changes are shown in italics:
2 3
A COT shall be the injection of a simulated or actual signal into the channel 4
as close to the sensor as practicable to verify OPERABILITY of all devices 5
in the channel required for channel OPERABILITY. The COT shall include 6
adjustments, as necessary, of the required alarm, interlock, and trip 7
setpoints required for channel OPERABILITY such that the setpoints are 8
within the necessary range and accuracy. The COT may be performed by 9
means of any series of sequential, overlapping, or total channel steps, and 10 each step must be performed within the Frequency in the Surveillance 11 Frequency Control Program for the devices included in the step.
12 13 A TADOT shall consist of operating the trip actuating device and verifying 14 the OPERABILITY of all devices in the channel required for trip actuating 15 device OPERABILITY. The TADOT shall include adjustment, as necessary, 16 of the trip actuating device so that it actuates at the required setpoint 17 within the necessary accuracy. The TADOT may be performed by means of 18 any series of sequential, overlapping, or total channel steps, and each step 19 must be performed within the Frequency in the Surveillance Frequency 20 Control Program for the devices included in the step.]
21 22 The various instrumentation functions in the TSs require surveillances to verify the correct 23 functioning of the instrument channel. The proposed change extends the definition of 24 instrumentation channel components to permit the surveillance frequency of each step to be 25 determined under the SFCP based on the component(s) surveilled in the step instead of all 26 components in the channel. This will allow each component to be tested at the appropriate 27 frequency based on the components long-term performance characteristics.
28 29 The proposed changes in the definition for instrument testing would allow the licensee to control 30 the frequency of associated components being tested in each step. The SR for the overall 31 instrumentation channel remains unchanged. The proposed change has no effect on the 32 design, fabrication, use, or methods of testing the instrumentation channels and will not affect 33 the ability of the instrumentation to perform the functions assumed in the safety analysis.
34 35 These instrumentation testing definitions state that, [t]he [test type] may be performed by 36 means of any series of sequential, overlapping, or total channel steps. The surveillance 37 frequency of these subsets would be established based on the characteristics of the 38 components in the step rather than the most limiting component characteristics in the entire 39 channel. Each of these steps are evaluated in accordance with the SFCP.
40 41 2.2.1 Variations from TSTF-563 42 43
{NOTE: Technical reviewers and/or project manager are to assess the adequacy of any 44 variations from the approved traveler and document their acceptability. Choose the applicable 45 paragraphs based on information provided in the LAR.}
46 47
[The licensee is proposing the following variations from the TS changes described in 48 TSTF-563 or the applicable parts of the NRC staffs SE of TSTF-563. [Describe the 49 variations and why TSTF-563 is still applicable.] These variations do not affect the 1
applicability of TSTF-563 or the NRC staff's SE to the proposed LAR.]
2 3
[The [PLANT] TSs utilize different [numbering][and][titles] than the Standard Technical 4
Specifications on which TSTF-563 was based. Specifically, [describe differences 5
between the plant-specific TS numbering and/or titles and the TSTF-563 numbering 6
and/or titles.] These differences are editorial and do not affect the applicability of 7
TSTF-563 to the proposed LAR.]
8 9
[The [PLANT] design is different than the model plant assumed in the Standard Technical 10 Specifications, but the TSTF-563 justification and the NRC staff's SE are still applicable.
11
[Describe differences and why TSTF-563 is still applicable.))
12 13 2.3 APPLICABLE REGULATORY REQUIREMENTS AND GUIDANCE 14 15 Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) requires each 16 applicant for a license authorizing operation of a utilization facility to include in the application 17 proposed TSs.
18 19 The regulation at 10 CFR 50.36(b) requires:
20 21 Each license authorizing operation of a utilization facility will include 22 technical specifications. The technical specifications will be derived from the 23 analyses and evaluation included in the safety analysis report, and amendments 24 thereto, submitted pursuant to [10 CFR] 50.34 [Contents of applications; 25 technical information]. 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). One such 29 category is SRs, which are defined in 10 CFR 50.36(c)(3) as requirements relating to test, 30 calibration, or inspection to assure that the necessary quality of systems and components is 31 maintained, that facility operation will be within safety limits, and that the limiting conditions for 32 operation will be met.
33 34 The regulation at 10 CFR 50.36(c)(5) requires TSs to include administrative controls, which are 35 the provisions relating to organization and management, procedures, recordkeeping, review and 36 audit, and reporting necessary to assure operation of the facility in a safe manner.
37 38 Traveler TSTF-425 revised and relocated most periodic surveillance frequencies to licensee 39 control. Changes to the relocated surveillance frequencies are made in accordance with the 40 SFCP. The SFCP requires that changes to the relocated frequencies be made in accordance 41 with NRC staff approved topical report NEI 04-10.
42 43 Topical report NEI 04-10 describes an evaluation process and a multi-disciplinary plant 44 decisionmaking panel that considers the detailed evaluation of proposed surveillance frequency 45 revisions. The evaluations are based on operating experience, test history, manufacturers 46 recommendations, codes and standards, and other deterministic factors, in conjunction with risk 47 insights. The evaluation considers all components being tested by the SR. Process elements 48 are included for determining the cumulative risk impact of the changes, updating the licensees 49 probabilistic risk assessment (PRA) models, and for imposing corrective actions, if necessary, 1
following implementation of a revised frequency.
2 3
The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of 4
NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for 5
Nuclear Power Plants: LWR [Light-Water Reactor] Edition (SRP), March 2010 (ADAMS 6
Accession No. ML100351425). As described therein, as part of the regulatory standardization 7
effort, the NRC staff has prepared STS for each of the LWR nuclear designs. Accordingly, the 8
NRC staffs review includes consideration of whether the proposed changes are consistent with 9
the applicable reference STS (i.e., the current STS), as modified by NRC-approved Travelers.
10 In addition, the guidance states that comparing the change to previous STS can help clarify the 11 TS intent.
12 13 Regulatory Guide (RG) 1.174, Revision 2, An Approach for Using Probabilistic Risk 14 Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis 15 (ADAMS Accession No. ML100910006), describes an acceptable risk-informed approach for 16 assessing the nature and impact of proposed permanent licensing basis changes by 17 considering engineering issues and applying risk insights. This regulatory guide also provides 18 risk acceptance guidelines for evaluating the results of such evaluations.
19 20 RG 1.177, Revision 1, An Approach for Plant-Specific, Risk-Informed Decisionmaking:
21 Technical Specifications (ADAMS Accession No. ML100910008), describes an acceptable 22 risk-informed approach specifically for assessing proposed TS changes.
23 24 RG 1.200, An Approach for Determining the Technical Adequacy of Probabilistic Risk 25 Assessment Results for Risk-Informed Activities (ADAMS Accession No. ML090410014),
26 describes an acceptable approach for determining the technical adequacy of PRAs.
27 28 The NRC staffs guidance for evaluating the technical basis for proposed risk-informed 29 changes is provided in SRP, Chapter 19, Section 19.2, Review of Risk Information Used to 30 Support Permanent Plant-Specific Changes to the Licensing Basis: General Guidance 31 (ADAMS Accession No. ML071700658). The NRC staffs guidance on evaluating PRA 32 technical adequacy is provided in SRP, Chapter 19, Section 19.1, Revision 3, Determining the 33 Technical Adequacy of Probabilistic Risk Assessment for Risk-Informed License Amendment 34 Requests After Initial Fuel Load (ADAMS Accession No. ML12193A107). More specific 35 guidance related to risk-informed TS changes is provided in SRP, Chapter 16, Section 16.1, 36 Revision 1, Risk-Informed Decision Making: Technical Specifications (ADAMS Accession 37 No. ML070380228), which includes changes to surveillance test intervals (STIs) (i.e.,
38 surveillance frequencies) as part of risk-informed decisionmaking. Section 19.2 of the SRP 39 references the same criteria as RG 1.177, Revision 1, and RG 1.174, Revision 2, and states 40 that a risk-informed application should be evaluated to ensure that the proposed changes meet 41 the following key principles:
42 43 The proposed change meets the current regulations, unless it explicitly relates to a 44 requested exemption or rule change.
45 46 The proposed change is consistent with the defense-in-depth philosophy.
47 48 The proposed change maintains sufficient safety margins.
49 50 When proposed changes result in an increase in risk associated with core damage 1
frequency or large early release frequency, the increase(s) should be small and 2
consistent with the intent of the Commissions Safety Goal Policy Statement.
3 4
The impact of the proposed change should be monitored using performance 5
measurement strategies.
6 7
{NOTE: Choose applicable STS}
8
[U.S. Nuclear Regulatory Commission, Standard Technical Specifications, Babcock and 9
Wilcox Plants, NUREG-1430, Volume 1, Specifications, and Volume 2, Bases, 10 Revision 4.0, dated April 2012 (ADAMS Accession Nos. ML12100A177 and ML12100A178, 11 respectively).
12 13 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, Westinghouse 14 Plants, NUREG-1431, Volume 1, Specifications, and Volume 2, Bases, Revision 4.0, 15 dated April 2012 (ADAMS Accession Nos. ML12100A222 and ML12100A228, respectively).
16 17 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, Combustion 18 Engineering Plants, NUREG-1432, Volume 1, Specifications, and Volume 2, Bases, 19 Revision 4.0, dated April 2012 (ADAMS Accession Nos. ML12102A165 and ML12102A169, 20 respectively).
21 22 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General 23 Electric BWR/4 Plants NUREG-1433, Volume 1, Specifications, and Volume 2, Bases, 24 Revision 4.0, dated April 2012 (ADAMS Accession Nos. ML12104A192 and ML12104A193, 25 respectively).
26 27 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General 28 Electric BWR/6 Plants NUREG-1434, Volume 1, Specifications, and Volume 2, Bases, 29 Revision 4.0, dated April 2012 (ADAMS Accession Nos. ML12104A195 and ML12104A196, 30 respectively).]
31 32
3.0 TECHNICAL EVALUATION
33 34 Revising the frequency of a Channel Calibration(( and Channel Functional Test] OR [, COT, 35 and TADOT)) instrument channel under the SFCP requires assurance that component 36 performance characteristics, such as drift between each test, will not result in undetected 37 instrument errors that exceed the assumptions of the safety analysis and supporting instrument 38 loop uncertainty calculations. These requirements are consistent with the methodology 39 described in NEI 04-10, which the SFCP requires to be followed. The SFCP does not permit 40 changes to the TS Allowable Values or Nominal Trip Setpoints; but allows only the surveillance 41 frequency to be changed when determined permissible by NEI 04-10. Therefore, prior to 42 extending the test intervals for an instrument channel component or components associated 43 with a given calibration step, the component performance characteristics must be evaluated to 44 verify the Allowable Value or Nominal Trip Setpoint will still be valid and to establish a firm 45 technical basis supporting the extension. In addition, each change must be reviewed by the 46 licensee to ensure the applicable uncertainty allowances are conservative (bounding) (e.g.,
47 sensor drift, rack drift, indicator drift). Documentation to support the changes shall be retained 48 per the guidance in NEI 04-10.
49 50 Five key safety principles that must be evaluated before changing any surveillance frequency 1
are identified in Section 3.0 of NEI 04-10. Principle 3 requires confirmation of the maintenance 2
of safety margins, which, in this case, includes performance of deterministic evaluations to 3
verify preservation of instrumentation trip setpoint and indication safety margins.
4 5
The evaluation methodology specified in NEI 04-10 also requires consideration of common 6
cause failure effects and monitoring of the instrument channel component performance 7
following the frequency change to ensure channel performance is consistent with the analysis to 8
support an extended frequency.
9 10 The method of evaluating a proposed surveillance frequency change is not dependent on the 11 number of components in the channel. Each step needs to be evaluated to determine the 12 acceptable surveillance frequency for that step. The proposed change to permit changing the 13 surveillance frequency of channel component(s) does not affect the test method or evaluation 14 method. The requirement to perform a Channel Calibration, Channel Functional Test, COT, or 15 TADOT on the entire channel is not changed.
16 17 For example, an evaluation in accordance with NEI 04-10 may determine that a field sensor 18 (e.g., a transmitter) should be calibrated every 48 months, the rack modules should be 19 calibrated every 30 months, and the indicators should be calibrated every 24 months. Under 20 the current TS requirements, all devices in the channel must be calibrated every 24 months.
21 However, under the proposed change, sensors, rack modules, and indicators would be 22 calibrated at the appropriate frequency for the tested devices. As required by the Channel 23 Calibration definition, the test would still encompass all devices in the channel required for 24 channel operability.
25 26 The NEI 04-10 methodology is used to evaluate surveillance frequency changes to determine if 27 such SR extensions could be applied. Process elements are used to determine the cumulative 28 risk impact of changes, updating the PRA, and imposition of corrective actions, if needed, 29 following implementation. Several steps are required by NEI 04-10, Step 7, to be evaluated 30 prior to determining the acceptability of changes. These steps include history of surveillance 31 tests, industry and plant specific history, impact on defense-in-depth, vendor recommendations, 32 required test frequencies for the applicable codes and standards, ensuring that plant licensing 33 basis would not be invalidated and other factors. The NRC staff finds these measures 34 acceptable in determining the SR extensions.
35 36 In addition, Step 16 of Section 4.0 of NEI 04-10 requires an Independent Decisionmaking Panel 37 (IDP) to review the cumulative impact of all STI changes over a period of time. This is also 38 required by RGs 1.174 and 1.177. The IDP is comprised of the site Maintenance Rule Expert 39 Panel, Surveillance Test Coordinator, and Subject Matter Expert who is a cognizant system 40 manager or component engineer. Based on the above information, the NRC staff finds that the 41 setpoint changes will be tracked in an acceptable manner.
42 43 Licensees with an SFCP may currently revise the surveillance frequency of instrumentation 44 channels. The testing of these channels may be performed by means of any series, sequential, 45 overlapping, or total channel steps. However, all required components in the instrumentation 46 channel must be tested in order for the entire channel to be considered Operable.
47 48 The NRC staff notes that industry practice is to perform instrument channel surveillances, such 49 as Channel Calibrations and Channel Functional Tests, using separate procedures based on 50 the location of the components. Each of these procedures may be considered a step. The 1
results of all these procedures are used to satisfy the SR using the existing allowance to 2
perform it by means of any series of sequential, overlapping, or total channel steps. The 3
proposed changes would allow for determining an acceptable surveillance frequency for each 4
step.
5 6
The NRC staff notes that the NEI 04-10 methodology includes the determination of whether the 7
structure, system, and components (SSCs) affected by a proposed change to a surveillance 8
frequency are modeled in the PRA. Where the SSC is directly or implicitly modeled, a 9
quantitative evaluation of the risk impact may be carried out. The methodology adjusts the 10 failure probability of the impacted SSCs based on the proposed change to the surveillance 11 frequency. Where the SSC is not modeled in the PRA, bounding analyses are performed to 12 characterize the impact of the proposed change to the surveillance frequency. Potential 13 impacts on the risk analyses due to screening criteria and truncation levels are addressed by 14 the requirements for PRA technical adequacy, consistent with the guidance contained in 15 RG 1.200, and by sensitivity studies identified in NEI 04-10. The licensee is not proposing to 16 change the methodology, or the acceptance criteria for extending STIs, and licensees will need 17 to changes in the frequency for performing each of the steps in the instrumentation surveillance 18 test per the methodology in NEI 04-10.
19 20 Therefore, the NRC staff concludes that the proposed change determine an acceptable test 21 frequency for individual steps within instrumentation channel surveillance tests is acceptable 22 because any extended STIs will be developed within the established constraints of the 23 SFCP and NEI 04-10.
24 25 The regulatory requirements in 10 CFR 50.36 are not specific regarding the frequency of 26 performing surveillance tests. The proposed change only affects the frequency of performance 27 and does not affect the surveillance testing method or acceptance criteria. Therefore, the 28 proposed change is consistent with the surveillance testing requirements of 10 CFR 50.36.
29 30 PRA Acceptability 31 32 The guidance in RG 1.200 states that the quality of a licensees PRA should be commensurate 33 with the safety significance of the proposed TS change and the role the PRA plays in justifying 34 the change. That is, the greater the change in risk or the greater the uncertainty in that risk as a 35 result of the requested TS change, or both, the more rigor that should go into ensuring the 36 quality of the PRA.
37 38 The NRC staff will have performed an assessment of the PRA models used to support the 39 approved SFCP that uses NEI 04-10, using the guidance of RG 1.200 to assure that the PRA 40 models are capable of determining the change in risk due to changes to surveillance 41 frequencies of SSCs, using plant-specific data and models. Capability Category II of the NRC-42 endorsed PRA standard is the target capability level for supporting requirements for the internal 43 events PRA for this application. Any identified deficiencies to those requirements are assessed 44 further to determine any impacts to proposed decreases to surveillance frequencies, including 45 the use of sensitivity studies where appropriate, in accordance with NEI 04-10.
46 47 The SFCP permits revising of the surveillance frequency for instrumentation channels. The 48 NRC staff evaluated whether NEI 04-10 can be applied to subsets in an instrument channel 49 when the SFCP currently specifies a surveillance interval that is applied to the entire channel.
50 The NRC staff notes that the current channel surveillance may be performed by means of any 1
series of sequential, overlapping, or total channel steps. In practice, this means that a channel 2
is divided into subsets and each subset is tested separately. Therefore, the current instrument 3
channel testing is already composed of a sequence of individual tests.
4 5
The instrument function may be modeled in the PRA differently depending on the site and the 6
function (e.g., channel may be modeled individually, subsets may be modeled, or the channel 7
function may be modeled as a single entity). There are different steps through the evaluation 8
methodology in NEI 04-10 that could be used based on the different PRA modeling approaches.
9 The appropriate modeling of these different approaches is included in the NRC staffs review of 10 the PRA modeling during the review of the application to implement an SFCP that uses 11 NEI 04-10.
12 13 The licensee is using a PRA that was used to support their application that implemented an 14 SFCP that uses NEI 04-10. The amendment will change the capability of the licensee to 15 change the surveillance frequency of an entire channel to now change the frequency of each 16 subset of the channel. The NRC staff finds that changes to the surveillance frequency caused 17 by defining and using individual, testable component subsets can be appropriately evaluated 18 with the current SFCP and the current PRAs. The NRC staff finds that the risk-informed 19 methodology review and the PRA acceptability review that was performed during the review of 20 the licensees application to implement an SFCP that uses NEI 04-10 is adequate.
21 22 The NRC staff determined that the proposed changes to the TS meet the standards for TS in 23 10 CFR 50.36(b). The regulations at 10 CFR 50.36 require that TSs include items in specified 24 categories, including SRs. The proposed changes modify the definitions applicable to 25 instrumentation channel components but do not alter the technical approach that was approved 26 by the NRC in NEI 04-10, and the TSs, as revised, continue to specify the appropriate SRs for 27 tests and inspections to ensure the necessary quality of affected SSCs is maintained.
28 29 Additionally, the changes to the TS were reviewed and found to be technically clear and 30 consistent with customary terminology and format in accordance with SRP Chapter 16.0. The 31 NRC staff reviewed the proposed changes against the regulations and concludes that the 32 changes continue to meet the requirements of Sections 50.36(b), 50.36(c)(3), and 50.36(c)(5),
33 of 10 CFR, for the reasons discussed above, and thus provide reasonable assurance that 34 adoption of these TSs will have the requisite requirements and controls to operate safely.
35 Therefore, the NRC staff concludes that the proposed TS changes are acceptable.
36 37
[3.1 VARIATIONS FROM TSTF-563 38 39 The licensee described variations from TSTF-563 in Section 2.2 of the LAR. The licensee 40 provided justification for the proposed variations and exceptions. The staff reviewed the 41 justifications and concluded the variations are [not] acceptable because.
42 43 The [PLANT] TSs utilize different [numbering][and][titles] than the Standard Technical 44 Specifications on which TSTF-563 was based. The NRC staff agrees these differences 45 are editorial and do not affect the applicability of TSTF-563 to the proposed LAR.]
46 47
4.0 STATE CONSULTATION
48 49
{This section is to be prepared by the plant project manager.}
50 1
In accordance with the Commissions regulations, the [Name of State] State official was notified 2
of the proposed issuance of the amendment(s) on [date]. The State official had [no]
3 comments. [If comments were provided, they should be addressed here.]
4 5
5.0 ENVIRONMENTAL CONSIDERATION
6 7
{This section is to be prepared by the plant project manager in accordance with current 8
procedures.}
9 10
6.0 CONCLUSION
11 12
{This section is to be prepared by the plant project manager.}
13 14 The Commission has concluded, based on the considerations discussed above, that: (1) there 15 is reasonable assurance that the health and safety of the public will not be endangered by 16 operation in the proposed manner, (2) there is reasonable assurance that such activities will be 17 conducted in compliance with the Commissions regulations, and (3) the issuance of the 18 amendment(s) will not be inimical to the common defense and security or to the health and 19 safety of the public.
20 21
7.0 REFERENCES
22 23
{Optional section to be prepared by the PM and primary reviewers. If document is publicly 24 available, the ADAMS Accession No. should be listed.}
25 26
{NOTE: These are the principal contributors for the model SE of the traveler. Replace these 27 names with those who prepared the plant-specific SE.}
28 29 Principal Contributors: M. Chernoff, NRR/DSS 30 G. Singh, NRR/DE 31 J. Evans, NRR/DRA 32 33 Date: September 20, 2018 34