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2018-6-20 Public Meeting - NEI Draft Presentation - an Alternate Approach to NUMARC 93-01
	ML18166A093
Person / Time
Site:	Nuclear Energy Institute
Issue date:	06/20/2018
From:	Burr J, Ellgass L, Linthicum R, Mclain M, Sibley C, Vaughn S, Zapetis J; Arizona Public Service Co, Exelon Corp, Nuclear Energy Institute, PWR Owners Group, Tennessee Valley Authority, Wolf Creek
To:	; Office of Nuclear Reactor Regulation
	Lewin A, NRR/DIRS, 415-2259
References
	Download: ML18166A093 (19)
	v • d • e

An Alternate Approach to NUMARC 93-01 Chuck Sibley (Wolf Creek)

Jenna Burr (Exelon)

Jim Zapetis (Exelon)

Mike McLain (APS)

Larry Ellgass (TVA)

Roy Linthicum (PWROG)

Steve Vaughn (NEI)

June 20, 2018

Outline

Background

Purpose

Proposed Changes

Overall Process

Proposed Pilot Effort

Challenges

Project Schedule

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Background===

Delivering the Nuclear Promise Initiative (early 2017)

Focus resources on high safety significant functions

Gain efficiencies in the interface between the Maintenance Rule program and other station programs

Leverage improvements in data collection/analysis and system monitoring

Purpose

Provide utilities with a risk-informed framework that supports the implementation and monitoring of a maintenance effectiveness program that complies with 10 CFR 50.65, effectively and efficiently leverages utility resources, and is focused on equipment performance commensurate with safety.

Proposed Changes

Focus energy on determining the effectiveness of the maintenance strategy, not whether performance criteria are met

- Address every High Safety Significant functional failure in near real time

- Trend Low Safety Significant failures in CAP and evaluate in the (a)(3) assessment

- Leverage the (a)(4) configuration risk management program (i.e.,

CDF Trending) for unavailability insights during the (a)(3) assessment

Consider using the Birnbaum importance measure as an additional tool in determining safety significance

Proposed Changes

Perform causal evaluations commensurate with safety

- A trend of low safety significant failures warrants an appropriate causal evaluation.

- All HSS functional failures and Plant Level Events warrant a near real time causal evaluation

Overall Process - The Start

Scoping Establish/Implement Maintenance

Safety Significance Determination Scoping Strategy - Establish HSS and LSS functions/SSCs considering insights from the Birnbaum importance measure (evaluated during pilot)

Establish/Implement Maintenance Safety Strategy (a)(1) - (a)(2)

Significance Determination - Currently well-established Determination equipment reliability program

(a)(1)-(a)(2) Determination

- Based on the effectiveness of the component-specific maintenance strategy

Overall Process - Steady State Establish/Implement Perform * (a)(1)-(a)(2) Determination Maintenance Maintenance - Based on the effectiveness of the Strategy Strategy component-specific maintenance strategy

(a)(1)

- Components that are not currently effectively controlled via preventive (a)(1) - (a)(2) maintenance (a)(1)

Determination (a)(2) * (a)(2)

- Components that are currently effectively controlled via preventive maintenance

Perform Maintenance Strategy

- Execute the planned preventive maintenance as described via the maintenance strategy

Overall Process - Reacting to Failures - Part I IR/CR for Scoped

Issue Report (IR)/Condition SSC Report (CR) Initiated

Plant Level Events (PLEs) receive Yes a CAP cause evaluation Plant Level

If the failure is associated with an CAP Cause Event?

Evaluation HSS function and is either a No Maintenance Rule Functional Yes failure (MRFF) or a Condition Yes Monitoring Event (CME) a CAP MRFF or HSS? cause evaluation is performed CME?

Overall Process - Reacting to Failures - Part II MRFF or Yes HSS?

LSS failures are inputs for CME?

trending under the (a)(3)

No No assessment

HSS failures that are not MRFF or CAP Cause CME are inputs for trending under Evaluation the (a)(3) assessment

If a trend is identified, a CAP cause evaluation is performed Yes Trend (a)(3) Assessment Identified?

Overall Process - (a)(1) Loop (a)(1) (a)(1) - (a)(2)

Determination

(a)(1) process is essentially the same Establish

Ensure that monitoring Corrective performance to goals is focused Actions and Goals on the effectiveness of changes to the Maintenance Strategy Monitor Performance to Goals No Yes Perform Cause Are Goals Met?

Evaluation

Overall Process - CDF Trending CAP Cause

Core Damage Frequency (CDF)

Evaluation Trending uses the (a)(4) configuration risk management process to provide unavailability Yes data for trending Trend (a)(3) Assessment Identified?

Both a holistic and detailed suite of unavailability data No CDF Trending

Overall Process - CDF Trending

Actual average CDF compared to present limits

Evaluate periods of higher risk

- Could they have been avoided?

- Indications of higher than average risk

- If evaluation results in changes to maintenance strategy, evaluate for (a)(1)

Overall Process - (a)(1) - (a)(2) Determination

If (a)(1) goals are met or there is a (a)(1)

(a)(1) - (a)(2) (a)(2) CAP cause evaluation performed Determination resulting from a PLE, HSS functional failure or CME, or identified trend from the (a)(3) assessment, then an (a)(1)-(a)(2)

Yes determination is performed CAP Cause Are Goals Met? Evaluation

Based on the (a)(1)-(a)(2) determination, the SSC is either placed in (a)(1) or (a)(2)

Overall Process - Example #1

Component: HPSI Injection Valve

Function: Indirect Radiation Release

Safety Significance: High

Description:

Body to bonnet leak estimated to exceed the TRM limit. Determined to be a MRFF. Cause: failure to follow work instructions resulting in an inadequate weld.

NUMARC 93-01: Performance criteria: 3 failures, 36 months, remained in (a)(2).

Proposed Process: (a)(1)-(a)(2) determination would consider changes to the maintenance strategy given the ineffectiveness of maintenance (inadequate weld).

Proposed Pilot Effort

At least one pilot in each Region

Some stations will pilot the entire MR program while others will pilot just several systems

Pilots will not be implementing the NUMARC 93-01 process in parallel for the systems being piloted

Pilot starts in 4th quarter 2018 or 1st quarter 2019

Challenges

Change management

Applicability of current enforcement and inspection guidance

50.65 is a performance-based rule

Project Schedule

September- Workshop/Training for pilot plants

Fall 2018 - Pilots develop station procedures

4th quarter 2018/1st quarter 2019 - Begin pilot process (1 year duration)

QUESTIONS?

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