ML24318B831

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TSTF Slides from 11/13/24 Implementation Workshop TSTF-585, Revise LCO 3.0.3 to Require Managing Risk
ML24318B831
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Site: Technical Specifications Task Force
Issue date: 11/13/2024
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Technical Specifications Task Force A Joint Owners Group Activity TSTF 1

TSTF-585, "Revise LCO 3.0.3 to Require Managing Risk,"

Implementation Workshop November 13, 2024

Technical Specifications Task Force A Joint Owners Group Activity TSTF INTRODUCTIONS & AGENDA 2

Technical Specifications Task Force A Joint Owners Group Activity TSTF Agenda

  • Revision of Other TS in Lieu of LCO 3.0.3 Entry
  • Risk Management Actions
  • Application of the Maintenance Rule Risk Assessment Tools
  • Case Studies 3

Technical Specifications Task Force A Joint Owners Group Activity TSTF OVERVIEW OF TSTF-585 REQUIREMENTS 4

Brian Mann TSTF Program Manager

Technical Specifications Task Force A Joint Owners Group Activity TSTF Why Revise LCO 3.0.3?

  • LCO 3.0.3 requires initiation of a plant shutdown within one hour of entry.

- It's based on the assumption that an immediate plant shutdown is always the safest course of action.

  • Operators are trained to perform a rapid shutdown under LCO 3.0.3. However:

- A shutdown is a major plant evolution that exercises an array of plant equipment and procedures. Some equipment will be inoperable if the plant is in LCO 3.0.3.

- A complex, infrequently performed, and time-limited shutdown should be avoided if plant risk is acceptable to provide the operators the opportunity to plan, respond, and potentially avoid the shutdown.

  • A review of ten years of LERs and Event Reports determined that more than half of the plant shutdowns initiated under LCO 3.0.3 could be avoided if licensees had some additional time to resolve the condition.

5

Technical Specifications Task Force A Joint Owners Group Activity TSTF TSTF-585 Evolution The TSTF first discussed the proposed revision to LCO 3.0.3 with the NRC in March 2020.

The TSTF and NRC held a workshop in October 2020 for a more detailed discussion.

- The NRC and TSTF agreed on the goals of the change, but the staff had questions on how it would be implemented.

The TSTF and NRC continued to discuss the traveler, with the TSTF providing drafts or submittals and the NRC providing comments or questions:

- Versions provided in April 2021, November 2021, March 2023, and December 2023.

- Multiple workshops and teleconferences were held to discuss the staff questions and comments.

There were many questions on the Maintenance Rule and how the risk assessment tools would be used to evaluate LCO 3.0.3 conditions.

In October 2022, the TSTF and NRC held a workshop that focused on the use of the Maintenance Rule risk assessment in TSTF-585.

This workshop is an extension of that 2022 meeting.

6

Technical Specifications Task Force A Joint Owners Group Activity TSTF Current LCO 3.0.3 LCO 3.0.3 requires a plant shutdown under three conditions:

1. An LCO is not met and the associated Actions are not met;
2. An LCO is not met and an associated Action is not provided; or
3. An LCO is not met and LCO 3.0.3 entry is directed by the associated Actions.

LCO 3.0.3 requires initiation of actions to shut down the plant within one hour.

- The one hour to prepare appeared in the 1980s versions of the standard TS with no explanation.

- GL 87-09 added the following Bases without discussion, One hour is allowed to prepare for an orderly shutdown before initiating a change in plant operation. This time permits the operator to coordinate the reduction in electrical generation with the load dispatcher to ensure the stability and availability of the electrical grid.

7

Technical Specifications Task Force A Joint Owners Group Activity TSTF Overview of TSTF-585 The three conditions for entering LCO 3.0.3 are unchanged.

The revised LCO 3.0.3 requires a risk assessment to be performed and the appropriate risk management actions to be implemented within six hours of entry into LCO 3.0.3.

If:

- Risk is assessed and deemed to be acceptable,

- Appropriate risk management actions have been implemented, and

- Entry into LCO 3.0.3 was unplanned, Then a delay time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after entry into LCO 3.0.3 is provided before initiating a shutdown.

Otherwise, a shutdown is initiated at the end of the six-hour period.

The shutdown requirements (e.g., lower Mode entry) in LCO 3.0.3 are unchanged.

8

Technical Specifications Task Force A Joint Owners Group Activity TSTF Revised LCO 3.0.3 PWR:

When an LCO is not met and the associated ACTIONS are not met, an associated ACTION is not provided, or if directed by the associated ACTIONS, the unit shall be placed in a MODE or other specified condition in which the LCO is not applicable.

Within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> perform a risk assessment addressing inoperable systems and components and implement appropriate risk management actions. If the risk assessment determines that continuing operation is acceptable, the appropriate risk management actions are implemented, and entry into LCO 3.0.3 was unplanned, then action shall be initiated within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to place the unit, as applicable, in:

a. MODE 3 within 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />,
b. MODE 4 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, and
c. MODE 5 within 60 hours6.944444e-4 days <br />0.0167 hours <br />9.920635e-5 weeks <br />2.283e-5 months <br />.

If the risk assessment determines that continuing operation is not acceptable, the risk assessment was not performed, the appropriate risk management actions were not implemented, or entry into LCO 3.0.3 was planned, then action shall be initiated to place the unit, as applicable, in:

a. MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />,
b. MODE 4 within 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />, and
c. MODE 5 within 42 hours4.861111e-4 days <br />0.0117 hours <br />6.944444e-5 weeks <br />1.5981e-5 months <br />.

All times are determined from entry into LCO 3.0.3.

Exceptions to this Specification are stated in the individual Specifications.

If corrective measures are completed that permit operation in accordance with the LCO or ACTIONS, then completion of the actions required by LCO 3.0.3 is not required.

LCO 3.0.3 is only applicable in MODES 1, 2, 3, and 4.

9 REVISE

Technical Specifications Task Force A Joint Owners Group Activity TSTF Why Six Hours?

  • Why are six hours provided to perform the risk assessment and implement the risk management actions?

- The earlier drafts provided one hour to assess and manage risk with provisions to "swap" from the one-hour delay time to the 24-hour delay time if the risk assessment or risk management action implementation occurred later.

  • This was confusing and complicated.

- The staff suggested proposing a longer period and requiring the risk assessment and risk management actions be completed within that time.

  • After discussing with industry experts, determined six hours was reasonable to perform the risk assessment, and implement appropriate risk management actions (brief staff, protect equipment, pre-stage FLEX equipment, set fire watches, etc.).

10

Technical Specifications Task Force A Joint Owners Group Activity TSTF Why Twenty-Four Hours?

  • Why is twenty-four hours provided prior to initiating a plant shutdown if the conditions are met?

- A review of the actions taken by licensees to ensure a safe evolution for planned shutdowns determined that 24-hours was an appropriate delay period if plant risk is acceptable.

  • Calling in additional staff,
  • Simulator refresher training,
  • Procedure reviews,
  • Coordinating with the load dispatcher
  • Also, 24-hours is a reasonable period to work to restore inoperable equipment, or to request and receive regulatory relief, if warranted.

11

Technical Specifications Task Force A Joint Owners Group Activity TSTF Meaning of "Risk is Assessed and Managed" What is meant by, risk is assessed and managed?

The requirement that risk be assessed and managed appears in:

- LCO 3.0.4 (Mode changes) (TSTF-359, approved 2003),

- LCO 3.0.8 (Nonfunctional Snubbers) (TSTF-372, approved 2005),

- LCO 3.0.9 (Nonfunctional Barriers) (TSTF-427, approved 2006), and

- SR 3.0.3 (Missed Surveillances) (TSTF-358, approved 2001).

In all of these cases and in TSTF-585, risk is assessed and managed using the existing 10 CFR 50.65(a)(4) tools. 50.65(a)(4) was promulgated in 1993.

- Section 11 of NUMARC 93-01, Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants,

- Endorsed by NRC Regulatory Guide 1.160, "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants."

- This will be discussed in detail later in the meeting.

12

Technical Specifications Task Force A Joint Owners Group Activity TSTF Meaning of "Risk is Assessed and Managed" TSTF-585 is not a risk informed traveler.

- The existing one-hour delay time is not based on risk.

- The proposed six-hour and 24-hour periods were not determined using risk.

- NRR LIC-206, "Integrated Risk-Informed Decision-Making for Licensing Reviews,"

discusses the difference between risk-informed submittals, submittals that utilize risk insights, and deterministic submittals.

- TSTF-585 leverages existing risk assessment methods implementing 10 CFR 50.65(a)(4) and does not include any PRA calculations or significant risk discussion.

- The existing tools are routinely inspected by NRC as part of the Maintenance Rule oversight.

- The traveler does not request NRC approval of those tools.

  • TSTF-585 does not contain PRA information or significant risk discussion (a Type 2 change).
  • TSTF-585 is a deterministic (Type 1) submittal, which "contains no PRA information and little to no risk discussion." The change to the delay time is a deterministically determined, administrative limit.

13

Technical Specifications Task Force A Joint Owners Group Activity TSTF Meaning of "Continuing Operation is Acceptable"

  • LCO 3.0.3 states, "If the risk assessment determines that continuing operation is acceptable,..."
  • NUMARC 93-01, Section 11.3.7.2 contains the following table regarding risk management actions:
  • This will be discussed in greater detail.

14

Technical Specifications Task Force A Joint Owners Group Activity TSTF Documentation Licensees log entry and exit from LCO 3.0.3. Logging practices are plant-specific but logging the entry into a TS Action is universally used.

NUMARC 93-01, Section 11.3.9, "Documentation," states:

- The normal work control process suffices as a record that the assessment was performed. It is not necessary to document the basis of each assessment for removal of equipment from service as long as the process is followed.

The LCO 3.0.4 Bases state that the LCO 3.0.4.b risk assessments do not have to be documented.

The SR 3.0.3 Bases discuss the reasonable expectation that an SR will be met with performed. It states:

- For Surveillances that have not been performed for a long period or that have never been performed, a rigorous evaluation based on objective evidence should provide a high degree of confidence that the equipment is OPERABLE. The evaluation should be documented in sufficient detail to allow a knowledgeable individual to understand the basis for the determination.

The TSTF sees this direction on documentation as a reasonable approach and will revise TSTF-585 to include this guidance.

15

Technical Specifications Task Force A Joint Owners Group Activity TSTF REVISION OF OTHER TS IN LIEU OF LCO 3.0.3 ENTRY 16 Brian Mann TSTF Program Manager

Technical Specifications Task Force A Joint Owners Group Activity TSTF Overview

  • At the October 2022 NRC/TSTF workshop, the NRC suggested that the traveler consider those TS Conditions in which the proposed 24-hour allowance would never be appropriate and incorporate TS restrictions, either by replacing the LCO 3.0.3 entry with shutdown requirements or making LCO 3.0.3 not applicable.
  • It's impossible to identify every circumstance under which LCO 3.0.3 could apply.
  • The TSTF also identified specifications that lacked Actions for obvious failures to meet the LCO, such as not providing an Action for two inoperable trains in specifications that require two trains to be operable.
  • The TSTF also reviewed the LERs and Event Reports from 2010-2022 describing situations in which LCO 3.0.3 was entered.

17

Technical Specifications Task Force A Joint Owners Group Activity TSTF Questions For each identified LCO 3.0.3 entry, the TSTF asked the following questions:

- Could the Condition affect safe plant operation assuming no other failures or accidents?

  • For example, loss of all DC distribution systems would have an immediate effect on plant safety due to loss of indication and control power regardless of whether a coincident DBA occurred.

- Could the Condition be assessed for its risk impact?

- Could the Condition be entered for failures that would not significantly degrade the ability of the system to perform its primary function?

  • For example, a component declared inoperable due to environmental qualification issues.

- Are there proceduralized actions that can be taken to diminish the impact of the failure?

- Would an immediate plant shutdown be complicated by the failure?

  • For example, all low pressure ECCS injection pumps inoperable when the pumps also are the RHR pumps.

18

Technical Specifications Task Force A Joint Owners Group Activity TSTF Other TS Changes

  • Based on the review, the TSTF-585 includes the following additional changes:

- NUREG-1430, TS 3.1.6, "Axial Power Shaping Rod (APSR) Alignment Limits," was revised to add an Action for more than one inoperable APSR. APSRs are not modeled in the PRA.

- NUREG-1431, TS 3.6.10, "Hydrogen Ignition System," was revised to add an action for both HIS trains inoperable or for a containment region with no operable HIS train. HIS is not modeled in the PRA.

- PWR NUREGs, TS 3.7.2, "Main Steam Isolation Valves," is modified to provide an Action when more than one MSIV is inoperable in Mode 1 that requires exiting Mode 1. This is an obvious omission and the MSIV Actions for Modes 2 and 3 are more appropriate than LCO 3.0.3.

19

Technical Specifications Task Force A Joint Owners Group Activity TSTF Other TS Changes

  • In PWR and BWR NUREGs, TS 3.8.4, "DC Sources - Operating," is revised to require a plant shutdown if both subsystems or divisions of DC power are inoperable. The condition would result in a loss of indication and control power and an immediate shutdown is appropriate.
  • In PWR and BWR NUREGs, TS 3.8.9, "Distribution Systems - Operating," is revised to require a plant shutdown if two or more inoperable subsystems or divisions result in a loss of safety function. In this condition, the remaining subsystems are no longer capable of supporting the minimum safety functions necessary to shut down the reactor and maintain it in a safe shutdown condition without assuming any additional failures and would likely result in a reactor trip.

20

Technical Specifications Task Force A Joint Owners Group Activity TSTF TS That Were Not Changed It's worth considering why some other systems were not included.

- The "ECCS - Operating" Actions for PWRs require entering LCO 3.0.3 when less than 100% of the ECCS flow equivalent to a single operable train is available. For BWRs, LCO 3.0.3 entry is required for several combinations of inoperable equipment that would prevent the ECCS from performing its required function.

- The TSTF determined that the proposed LCO 3.0.3 is appropriate for this condition. At most PWR and BWR plants, the low pressure ECCS components are also used for decay heat removal during shutdown. Requiring an immediate plant shutdown to a condition that could require the use of an inoperable decay heat removal system may be unwarranted. Also, high pressure injection is typically a low-risk system (risk informed Completion Times typically greater than 30 days).

- Therefore, we determined that the opportunity to assess risk in this situation and potentially provide time to respond is justified.

21

Technical Specifications Task Force A Joint Owners Group Activity TSTF TS That Were Not Changed

- The "AC Sources - Operating" specification requires entering LCO 3.0.3 when three or more required AC sources are inoperable.

- If both offsite circuits are inoperable, a plant trip will likely render LCO 3.0.3 entry moot.

- However, if the unit continues to operate in this TS condition (for example, if two DGs and one offsite circuit are inoperable), requiring an immediate plant shutdown and removal of the main generator as a power source may not be warranted.

- The proposed change does not alter the existing TS Actions that require restoring at least one of two inoperable DGs within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. If an offsite circuit and DG are both inoperable, the TS requires one to be restored within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. These Actions effectively limit the application of the proposed change to LCO 3.0.3.

- Therefore, we determined that the opportunity to assess risk in this situation and potentially provide time to respond is justified.

22

Technical Specifications Task Force A Joint Owners Group Activity TSTF TS That Were Not Changed

- These examples demonstrate that many systems or circumstances should be evaluated for the risk impact on the plant. If warranted, a delay to respond is appropriate. If not, a plant shutdown will be required.

23

Technical Specifications Task Force A Joint Owners Group Activity TSTF RISK MANAGEMENT ACTIONS (RMAs) 24 Drew Richards PWROG Vice Chair

Technical Specifications Task Force A Joint Owners Group Activity TSTF Background - NUMARC 93-01

  • NUMARC 93-01 (Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants), Section 11.3.7.5, Risk Management Actions:

- Risk management actions should be considered for configurations that result in a minimal increase from the plants baseline risk. [T]he benefits of these actions are generally not quantifiable. These actions are aimed at providing increased risk awareness of appropriate plant personnel, providing more rigorous planning and control of the activity, and taking measures to control the duration of the increased risk, and the magnitude of the increased risk.

25

Technical Specifications Task Force A Joint Owners Group Activity TSTF Risk-Management Action applicability

  • Risk-Management Actions (RMAs) are used in the following circumstances:

- Risk Informed Completion Times - planned and unplanned configurations (assess non-quantifiable factors)

- Routine maintenance activities - work week risk reduction (> 1E-06 Incremental Core Damage Probability)

- Tech Spec LCO 3.0.4.b - After performance of a risk assessment and establishment of risk management actions, if appropriate [W STS]

- Tech Spec SR 3.0.3 - Any [RMAs] recommended as part of the risk evaluation should be implemented at the earliest opportunity" [STP procedure 0POP01ZO0011]

26

Technical Specifications Task Force A Joint Owners Group Activity TSTF Maintenance Rule Thresholds 27

Technical Specifications Task Force A Joint Owners Group Activity TSTF Generic RMAs for Consideration (from NUMARC 93-01)

RMAs to provide increased risk awareness and control (*LCO 3.0.3 Likely Applicable)

- Discuss planned maintenance activity and the associated plant configuration risk impact with operations and maintenance shift crews and obtain operator awareness and approval of planned evolutions.

- *Conduct pre-job briefing of maintenance personnel, emphasizing risk aspects of plant evolutions.

- Request/require that system engineer(s) be present for the maintenance activity, or for applicable portions of the activity.

- Obtain station management approval of the proposed activity.

- *Identify return-to-service priorities.

- *Identify important remain-in-service priorities.

- *Place warning signs or placards in the entry ways to protect other in-service risk significant equipment.

28

Technical Specifications Task Force A Joint Owners Group Activity TSTF Generic RMAs for Consideration (continued)

RMAs to reduce duration of maintenance activity (*LCO 3.0.3 Likely Applicable)

-

  • Pre-stage required parts and materials accounting for likely contingencies.

- Walk-down the anticipated associated system tagout(s) and key equipment associated with the specified maintenance activity(ies) prior to conducting actual system tagout(s) and performing the maintenance.

- Develop critical activity procedures for risk-significant configurations, including identification of the associated risk and contingency plans for approaching/exceeding the RICT.

- Conduct training on mockups to familiarize maintenance personnel with the activity prior to performing the maintenance.

-

  • Perform maintenance around the clock rather than day-shift only.

-

  • Establish contingency plan to restore key out-of-service equipment rapidly if and when needed.

29

Technical Specifications Task Force A Joint Owners Group Activity TSTF Generic RMAs for Consideration (continued)

RMAs to minimize the magnitude of risk increase (*LCO 3.0.3 Likely Applicable)

-

  • Postpone plant activities, if appropriate, to maintain or reduce risk levels.

-

-

  • Identify remain-in-service priorities and minimize work in areas that could affect other redundant systems (e.g., SI & RHR rooms, auxiliary feedwater pump rooms), such that there is enhanced likelihood of the availability of the safety functions at issue served by the SSCs in those areas.

-

  • Establish alternate success paths (provided by either safety or non-safety related equipment) for performing the safety function of the out-of-service SSC.

-

  • Establish other compensatory measures as appropriate.

-

  • Return equipment to service to reduce risk levels.

-

  • Install/connect temporary equipment to substitute for permanent equipment that is out of service.

30

Technical Specifications Task Force A Joint Owners Group Activity TSTF Summary

  • RMAs have formally been around for about 30 years
  • RMAs address non-quantifiable factors
  • RMAs provide risk awareness
  • RMAs are integrated in the planning process
  • RMAs address risk magnitude and risk duration
  • RMAs are an integral part of the station risk culture 31

Technical Specifications Task Force A Joint Owners Group Activity TSTF APPLICATION OF THE MAINTENANCE RULE RISK ASSESSMENT TOOLS 32 Jim Lynde PWROG Chairman

Technical Specifications Task Force A Joint Owners Group Activity TSTF NUMARC 93-01 Risk Assessment Guidance The assessment method may use quantitative approaches, qualitative approaches, or blended methods. In general, the assessment should consider:

- Technical specifications requirements.

- The degree of redundancy available for performance of the safety function(s) served by the out-of-service SSC.

- The duration of the out-of-service or testing condition.

- The likelihood of an initiating event or accident that would require the performance of the affected safety function.

- The likelihood that the maintenance activity will significantly increase the frequency of a risk-significant initiating event (e.g., by an order of magnitude or more as determined by each licensee, consistent with its obligation to manage maintenance-related risk).

- Component and system dependencies that are affected

- Significant performance issues for the in-service redundant SSCs

- The risk impact of performing the maintenance during shutdown with respect to performing the maintenance at power.

- The impact of transition risk if the maintenance activity would require a shutdown that would otherwise not be necessary 33

Technical Specifications Task Force A Joint Owners Group Activity TSTF CASE STUDIES 34 Jim Lynde PWROG Chairman

Technical Specifications Task Force A Joint Owners Group Activity TSTF Introduction

  • The intention of the case studies is to illustrate how a licensee would use the existing 10 CFR 50.65(a)(4) tools to assess and manage risk when in LCO 3.0.3.
  • The NRC suggested several questions for the case studies. We will apply that approach for all of the case studies.

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be implemented?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

35

Technical Specifications Task Force A Joint Owners Group Activity TSTF Case Studies

1. PWR Loss of RCS Leakage Instrumentation
2. Loss of Two Trains of Safety Injection Pumps
3. Loss of Two Channels of High Containment Pressure
4. BWR Loss of RCS Leakage Instrumentation (NRC)
5. BWR/3 LPSI and Core Spray Inoperable (NRC)
6. PWR Essential Service Water Trains Inoperable (NRC) 36

Technical Specifications Task Force A Joint Owners Group Activity TSTF PWR Loss of RCS Leakage Instrumentation Westinghouse PWR has a failure of sump monitor power supply. As the maintenance crew prepares to perform emergent replacement of the power supply, the rad monitor check source window fails to fully close. The rad monitor fails to clear following the daily check source.

The TS Action for "All Required monitors inoperable" applies and directs immediate LCO 3.0.3 entry.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

37

Technical Specifications Task Force A Joint Owners Group Activity TSTF Loss of Two Trains of Safety Injection Pumps Westinghouse 4 loop plant has an ongoing maintenance window on the A train Safety Injection (SI) train. LCO 3.5.2, Condition A, "One train inoperable," is entered with a 7-day Completion Time.

After Maintenance has disassembled the SI pump for an overhaul, Operations noted a small through fitting leak on the lube oil line for the B train SI pump motor. Significant oil has drained from the B SI pump motor and no oil level is observed in the sight glass.

Two SI pumps inoperable would result in less than 100% of the flow equivalent to a single operable ECCS train. TS 3.5.2, Action C, directs immediate entry into LCO 3.0.3.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

38

Technical Specifications Task Force A Joint Owners Group Activity TSTF Loss of Two Channels of High Containment Pressure Westinghouse 4 loop plant has a failure of a containment pressure instrument used to initiate an automatic safety injection on high containment pressure (STS Function 1.c). TS 3.3.2, "ESFAS Instrumentation," Condition D, is entered.

The replacement of the instrument in containment would require two channels to be isolated for a duration of several hours. TS 3.3.2 has no Condition for two inoperable channels for this Function and entry into 3.0.3 is required.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

39

Technical Specifications Task Force A Joint Owners Group Activity TSTF BWR Loss of RCS Leakage Instrumentation BWR-4 with Mk-1 containment that is operating at 100% thermal power. high pressure coolant injection (HPCI) system was taken out of service for planned maintenance and declared inoperable on Monday at 0100 (T=0) and the unit is currently in LCO 3.5.1, Condition C.

At T=64h, 39m, Reactor Protection System (RPS) Bus 1A failed. Primary Containment Isolation System (PCIS) Groups 2, 3, 6, and 8 isolated in response to this event. The isolation rendered the RCS leakage detection instrumentation inoperable. TS LCO 3.4.5, Condition D, required entering LCO 3.0.3 immediately. Assume that LCO 3.0.3 is entered at T=65 hours.

At approximately T=67h, its determined that power to the RCS Leakage Detection Instrumentation systems cannot be restored until T=97 hours.

At T=90h, high winds occur.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

40

Technical Specifications Task Force A Joint Owners Group Activity TSTF BWR/3 LPCI and Core Spray Inoperable BWR/3 operating at 100% RTP. Division 2 of low-pressure coolant injection (LPCI) subsystem is declared inoperable for planned maintenance on Monday at 0100 (T=0) and the unit is currently in plant-specific LCO 3.5.1, Condition B.

At T=66 hours, Division 1 Core Spray is also declared inoperable. Plant-specific Condition K requires entering LCO 3.0.3 immediately.

The other Division 1 pumps will not be restored until T=90 h. The originally inoperable Division 1 LPCI pump wont be restored until T=138 h.

At T=81h 45m, LCO 3.8.1, Condition A, is entered for an inoperable offsite source.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

41

Technical Specifications Task Force A Joint Owners Group Activity TSTF PWR Essential Service Water Trains Inoperable Westinghouse 4 loop plant operating at 100% RTP. This plant-specific scenario requires the opposite unit Essential Service Water (SX) to be operable and a cross-tie between units is credited in the licensing basis.

At T=0, Train 1A of SX is declared inoperable for maintenance and TS 3.7.8, Condition A, entered. Required Action A.1 requires restoration by T=72 hours.

At T=33 h, the Train 1B of SX is declared inoperable. There is no Condition for two unit-specific SX trains inoperable, so LCO 3.0.3 is entered.

At T=43h, the 1B SX pump is secured. Train 1B is already inoperable.

Questions:

- What actions would the senior licensed operator responsible for plant operation take?

- What would be the likely outcome of the risk assessment and what risk management actions would likely be required by LCO 3.0.3?

- What aspects of the risk assessment would be captured in documentation?

- Would the condition qualify for the additional time permitted by LCO 3.0.3?

42

Technical Specifications Task Force A Joint Owners Group Activity TSTF CONCLUSION 43

Technical Specifications Task Force A Joint Owners Group Activity TSTF Next Steps

  • Discuss any suggested revisions to TSTF-585.
  • Schedule the next steps.

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