IP 71111.20, Refueling and Other Outage Activities

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Refueling and Other Outage Activities


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Issue Date: 11/28/17 1 71111.20

NRC INSPECTION MANUAL IRIB

INSPECTION PROCEDURE 71111 ATTACHMENT 20

REFUELING AND OTHER OUTAGE ACTIVITIES

Effective Date: January 1, 2018

PROGRAM APPLICABILITY: 2515 Appendix A

CORNERSTONE: Initiating Events

Mitigating Systems

Barrier Integrity

INSPECTION BASES: See IMC 0308, Attachment 2

SAMPLE REQUIREMENTS:

Sample Requirements Minimum Baseline Sample

Completion Requirements

Nominals and Budget

Sample Type Section Frequency Sample Size Samples Hours per site

Refueling/Other

Outage

03.01 One Each Outage* 1 unit: 71+/-15

2 units: 77+/-15

3 units: 81+/-15

  • An outage is a shutdown with a plant cooldown or a shutdown for containment entry, or both.

71111.20-01 INSPECTION OBJECTIVES

01.01 To verify that outage activities important to safety are appropriately managed.

01.02 To verify that safety-related and risk-significant structures, systems, and components in

inaccessible areas during power operations are appropriately maintained to support

required safety functions.

01.03 To verify that risk is appropriately managed during outage-related activities such as

during reduced-inventory and midloop conditions.

71111.20-02 GENERAL GUIDANCE

Use Inspection Procedure (IP) 71153, “Follow-Up of Events and Notices of Enforcement

Discretion,” for noncomplicated reactor trips where a startup is performed without entering the

containment. Use IP 71111.19, “Post-Maintenance Testing,” and IP 71111.22, “Surveillance

Testing,” to address testing activities that normally occur during refueling outages, such as

physics testing, emergency diesel generator time response testing, reactor coolant system

(RCS) hydrostatic testing, control rod scram time testing, rod drop time testing, reactor trip

Issue Date: 11/28/17 2 71111.20

breaker testing, and containment sump valve testing. However, IP 71111.20 should take

precedence for outage planning and configuration management reviews in areas where it

overlaps with other areas that require inspections, such as maintenance risk assessments and

emergent work control, equipment alignment, and inservice inspection activities.

IMC 0609, “Significance Determination Process,” Appendix G, “Shutdown Operations

Significance Determination Process,” contains checklists for various plant configurations that

can be used to assess mitigating capability. Higher risk configurations have more checklist

guidelines for each safety function. The following examples are high-risk configurations:

 pressurized-water reactors (PWRs)

 breached RCS boundary with steam generators that cannot be used for decay

heat removal (DHR)

 midloop conditions under which it is more likely that DHR can be lost because of

poor RCS-level control or poor DHR flow control

 boiling-water reactors (BWRs)

 cold shutdown conditions (i.e., technical specifications (TS) allow more

equipment to be inoperable during cold shutdown conditions than they do during

hot shutdown conditions)

inoperable safety relief valves under conditions in which such valves would be

needed to provide an alternate DHR path and pressure control during a loss of

the primary DHR system

For each sample, conduct a routine review of problem identification and resolution activities

using IP 71152, “Problem Identification and Resolution.”

Sample Considerations

Risk Priority Examples

Equipment or actions that could cause a loss of

DHR

Actions that could affect reactor vessel level

Activities that contribute to loss of offsite power

or station blackout

Inadvertent lowering of the reactor vessel

level in midloop as a result of operator

inattention

Improper hanging or restoration of clearance

tags that could affect reactor vessel level,

DHR, or electrical power availability

Actions that could cause the reactor vessel

level indication to be inaccurate.

Issue Date: 11/28/17 3 71111.20

Risk Priority Examples

Equipment used to mitigate a loss of DHR

Equipment used to mitigate a loss of reactor

vessel level

Activities that affect the ability of pumps

designated in the shutdown risk analysis to

add water to the reactor vessel

Activities that affect the water source for any

of the pumps designated in the shutdown

risk analysis

Activities that affect the electrical power

sources designated in the shutdown risk

analysis

Failure to verify refueling interlocks

Actions that affect the fuel cladding barrier,

reactor vessel/RCS integrity, or containment

integrity

Exceedance of heatup or cooldown rate

limits

Failure to establish containment integrity

during fuel movement

71111.20-03 INSPECTION SAMPLE

03.01 Refueling/Other Outage Sample

a. Outage Plan.

Before a planned outage, verify that the outage and risk control plan

appropriately considers risk, industry experience, and previous site-specific

problems.

Specific Guidance

1. Review the licensee’s outage risk control plan, related industry experience, and

previous site-specific problems. Confirm that the licensee has

mitigation/response strategies for losses of key safety functions.

2. Verify that the licensee maintains defense in depth. Evaluate risk insights

regarding the outage plan, including consideration of the overlap of work

activities, the handling of heavy loads, the erection of scaffolding, and the

increased potential for a fire or internal flooding. Verify that configuration

changes are controlled in accordance with the outage risk control plan and

applicable TS.

b. Fatigue Management.

Verify that the licensee manages worker fatigue appropriately during the outage.

Specific Guidance

Verify that the licensee has developed outage personnel work schedules that comply with Title 10 of the Code of Federal Regulations (10 CFR) 26.205(d)(4) and (5).

Consider the following:

1. Outage Work Schedules.

Review individual outage work schedules for operations, maintenance, and fire brigade personnel. Verify that the personnel who are working on outage activities are provided with the minimum days off to minimize the effects of cumulative fatigue. For multiple-unit sites, verify that the applicable control room staff for the operating unit remains on operating unit work hours control as specified in Regulatory Guide 5.73, “Fatigue Management for Nuclear Power Plant Personnel.” Verify that the reactor operators and senior reactor operators on the operating unit, if applicable, are under operating hours control and are not allowed the less-restrictive minimum days off requirements for outage activities. IP 93002, “Managing Fatigue,” provides additional guidance.

2. Waiver Requests, Self-Declarations, and Assessments.

Once during the outage, review three to five waiver requests (10 CFR 26.207, “Waivers and Exceptions”); self-declarations (10 CFR 26.209, “Self-Declarations”); and fatigue assessments (10 CFR 26.211, “Fatigue Assessments”), when they are available. Verify that the licensee is managing operator fatigue appropriately. IP 93002 provides additional guidance.

c. Shutdown.

Verify that the licensee conducts plant shutdown activities appropriately through the following activities:

1. Cooldown.

Observe portions of the cooldown process to verify that TS cooldown restrictions are followed.

2. Containment Opening.

If the containment is opened, conduct a walkdown of the containment promptly after it is opened.

Specific Guidance

If containment entry is available, conduct a thorough containment walkdown as soon as reasonably possible after shutdown to inspect plant areas that are inaccessible during power operations.

(a) Consider the following:
(1) ”as low as is reasonably achievable” controls
(2) industrial/personnel safety (heat stress)
(3) outage duration
(4) unidentified RCS leakage before shutdown
(b) Verify that structures, piping, and supports in containment do not include stains or deposited material that may indicate an unidentified RCS leakage. Verify that there is no evidence of RCS leakage (e.g., boric acid residue) that might later become obscured resulting from licensee outage work. IP 71111.08, “Inservice Inspection Activities,” requires an independent review of plant areas in which the licensee has recently conducted a boric acid walkdown.
(c) Verify that the containment sump is undamaged and debris free.
(d) Verify that supports, braces, and snubbers have no damage or deformation. Verify that hydraulic snubbers have no hydraulic fluid leaks and that the hydraulic fluid reservoir is adequately filled.
(e) Check for items that may be indicative of a larger problem. These problems may include, but are not limited to, the following:
(1) blistered paint and rust on containment liners
(2) leakage from containment ventilation and cooling systems
(3) cracks in concrete support structures
(4) damaged cable insulation
(5) presence of loose foreign material
(6) presence of temporary plant equipment left or stored in containment that the licensee’s design-basis analyses may not have considered

d. Outage.

Verify that the licensee has conducted outage-related activities appropriately.

Specific Guidance

Verify that the license maintains defense-in-depth when equipment is taken out of service. Verify that the licensee controls configuration changes in accordance with the outage risk control plan and applicable TS.

1. Isolation and Clearance/Cleanliness Activities.

Verify that tags are properly hung and removed and that associated equipment is appropriately configured to support the function during clearance restoration.

Specific Guidance

Examples of risk-significant clearance activities include the opening of water system boundaries for maintenance near risk-important equipment and power restorations that could adversely affect safety systems, such as the improper repositioning of a motor-operated value upon restoration of power. Pay particular attention to maintenance activities that could affect RCS, DHR, or spent fuel pool cooling.

2. Foreign Material Exclusion.

Verify that the licensee is implementing appropriate foreign material exclusion practices.

Specific Guidance

Review foreign material exclusion logs and records.

3. Reactor Coolant System Instrumentation.

Verify that RCS pressure, level, and

temperature instruments have been installed, calibrated, and configured to

provide accurate indications.

Specific Guidance

For level instruments, verify that the tubing runs do not have elevation changes

that could trap either liquid or vapor/gas in the instrument lines (i.e., loop seals).

If the plant uses normal operating level instrumentation, verify that the operators

have considered the effects of changes in water density (resulting from lower

temperature). Verify that the operators are aware of the effect of loss of DHR on

the plant's level instrumentation resulting from heatup and pressurization.

For temperature instruments, verify that the operators are aware of the effect of

loss of DHR on the plant’s temperature indication and the potential for

discrepancies between the temperature indications and the actual plant state.

Temperature may be measured in the DHR loop; in this case interruption,

bypass, or partial bypass of DHR flow could lead to incorrect and

nonconservative temperature indications.

4. Electrical Power.

Verify that the status and configurations of electrical

systems meet TS requirements and the licensee’s outage risk control plan.

Specific Guidance

Verify that switchyard activities are controlled commensurate with safety and are

consistent with the licensee’s outage risk control plan assumptions.

5. Containment.

Verify that the plant has the proper containment configuration

during risk-significant evolutions (e.g., PWR midloop operations, BWR

cavity drain down), including provisions for achieving prompt containment

closure during periods when containment is permitted to be open.

Specific Guidance

For BWRs, verify that secondary containment meets the TS requirements. Verify

that the containment closure procedures are available and that the licensee uses

them when applicable.

For PWRs, verify that containment penetrations meet TS requirements and that

containment closure1 can be achieved at all times.

1 Licensees of PWRs meet containment closure if all containment penetrations (including

temporary penetrations, the equipment hatch, and the personnel hatch) have a

6. Decay Heat Removal.

Observe DHR parameters to verify proper system

operation.

Specific Guidance

For BWRs, verify that training and procedures are in place for alternate DHR

systems.

For PWRs, when the licensee is relying on the steam generators to provide a

backup means of DHR by single-phase natural circulation, verify that the licensee

has confirmed the viability of this cooling method.

When the licensee is relying on the steam generators to provide a backup means

of DHR by single-phase natural circulation, verify the following:

(a) Procedures for these methods are derived from analyses, and the

required equipment is available.

(b) The RCS pressure boundary is closed.

(c) Steam generator tubes are full.

(d) Pressure control capability in the RCS is maintained to ensure the

subcooling margin.

(e) The plant has the capability to feed the steam generators.

(f) The plant has the capability to remove steam from the steam generators

(e.g., atmospheric relief valves, condenser with steam dump capability).

7. Inventory Control.

Verify that the flowpaths, configurations, and alternative

means for inventory addition are consistent with the outage risk plan.

Specific Guidance

For activities that have the potential to cause a loss of inventory, verify that

adequate controls are in place to prevent inventory loss. RCS pressure

boundary problems can pose significant shutdown risk.

(a) Examples of loss of inventory paths include the following:

(1) on BWRs—DHR to the suppression pool

differential capability equal to the ultimate pressure or would be expected to remain

intact following an accident. Leakage requirements, as described in Appendix J, are not

a concern. Results from the shutdown probabilistic risk analysis that the Office of

Nuclear Regulatory Research conducted at Surry Power Station shows that containment

pressure (in a subatmospheric containment) can be high at shutdown after a core

damage event.

(2) on BWRs—main steamline paths, including safety relief value

removal, automatic depressurization system testing, and main

steam isolation valve maintenance

(3) on PWRs—DHR system crosstie valves, thimble tube seals, and

steam generator nozzle dams

(4) maintenance activities on connected piping or components that

are at an elevation lower than the vessel flange on all plants

(5) paths for an intersystem loss-of-coolant accident, such as

maintenance and testing on the nonoperating loop low-pressure

injection (LPI) train or LPI testing on return back to the refueling

water storage tank

(b) For BWRs, verify the following:

(1) The automatic isolation on low level is aligned in accordance with

TS requirements that apply to the mode.

(2) The main steamline plugs are installed, and the systems required

for proper operation of the reactor cavity seal (e.g., instrument air)

are maintained to prevent seal failure.

(3) The plant has adequate vents to accomplish gravity feed and

low-pressure makeup when relied upon.

8. Reduced Inventory. Verify that the licensee safely controls plant conditions

during reduced inventory and midloop operations.

Specific Guidance

For BWR licensees that have adopted reactor pressure vessel water inventory

control, review the licensees’ drain time calculation and calculation assumptions.

Verify that the plant water inventory levels and limiting drain rate are consistent

with plant conditions. Verify that TS-required equipment and instrumentation is in

the required configuration.

For all other licensees, review their commitments from Generic Letter 88-17,

“Loss of Decay Heat Removal,” dated October 17, 1988, and confirm by

sampling that they are still in place and adequate. Review the

unit/outage-specific time-to-boil curves. During midloop operations, observe the

effect of distractions from unexpected conditions or emergent activities on the

operator’s ability to maintain the required reactor vessel level. In addition to

reduced inventory and midloop conditions, assess planned outage activities

occurring during other periods when there is a short time-to-boil.

Verify the following:

(a) The licensee has reviewed its controls and administrative procedures

governing midloop operation and has conducted training for midloop

operations.

(b) The licensee uses procedures for the following:

(1) identifying unexpected RCS inventory changes and verifying that

an RCS vent path is adequate during RCS draining to midloop

(2) emergency/abnormal operation during reduced inventory

(c) Indications of core exit temperature are operable and periodically

monitored (typically at least two independent and continuous indications).

(d) Indications of RCS water level are operable and periodically monitored

(typically at least two independent and continuous indications).

(e) RCS perturbations are avoided.

(f) Means of adding inventory to the RCS are available (typically at least two

means in addition to residual heat removal pumps).

(g) Reasonable assurance is obtained that not all hot legs are simultaneously

blocked by nozzle dams unless the upper plenum is vented.

(h) Contingency plans exist to repower vital electrical busses from an

alternate source if the primary source is lost.

The time-to-boil period can be less than 30 minutes when DHR is lost under

midloop conditions. During midloop operations, the operator provides the only

prevention/mitigating function for a loss of reactor vessel level before the loss of

DHR. The plant does not generally have alarms that indicate a loss of level

under midloop conditions. The operator’s attention to plant conditions is the key

preventative aspect for a loss of DHR event. Closely observe the operator’s

performance during drain down, and frequently observe control room activities

while the plant is under reduced inventory or midloop conditions. Observe how

potential control distractions, such as unexpected conditions and emergent work,

affect the operator’s focus.

9. Spent Fuel Pool Cooling.

Verify that outage work is not affecting the ability

of the operations staff to operate the spent fuel pool cooling system during

and after core offload.

Specific Guidance

Verify the following:

(a) Spent fuel pool cooling recovery procedures exist for situations that

involve loss of spent fuel pool cooling and are based on current/bounding

heat loads.

(b) Operators are trained on backup equipment and procedures for loss of

spent fuel cooling.

(c) Equipment designated in the recovery procedures is readily available, is

dedicated, is unobstructed by outage activities, and has compatible

equipment connections.

(d) Instrumentation, alarms, equipment, instructions, and training are

provided to alert operators of the need, and to enable them, to add water

to the spent fuel pool when necessary.

10. Refueling.

Verify that the licensee conducts reactor core refueling activities

appropriately.

Specific Guidance

Verify the following:

(a) Fuel handling operations (removal, inspection, sipping, reconstitution, and

insertion) and other ongoing activities are being performed in accordance

with TS requirements and approved procedures.

(b) Refueling seals have been properly installed and tested, and foreign

material exclusion is being maintained in the refueling, spent fuel, and

suppression pool areas.

(c) Fuel assembly locations are being tracked, including new fuel, from core

offload through core reload. Verify that coupling between the reactivity

monitoring instruments and fuel loading location within the core is

maintained.

(d) Fuel assembles are loaded in the reactor core locations as specified by

the design. Verify fuel assembly loading by reviewing video recording,

other core loading records, or physics testing results with as-predicted

core operating limit parameters.

(e) Discharged fuel assemblies are placed in allowable locations in the spent

fuel pool.

11. Reactivity Control.

Verify that reactivity is being controlled in accordance

with the TS. Verify that the outage risk plan identifies activities or

structures, systems, and components that could cause unexpected

reactivity changes and that the licensee is controlling them accordingly.

Specific Guidance

For PWRs, verify that the licensee has implemented appropriate administrative

controls on potential boron dilution paths. Verify that the licensee has

established adequate controls during refueling to preclude improper sequencing

of control rods or fuel assemblies to prevent any approach to criticality in any

core region without early source range monitor detection.

e. Startup.

Verify that the licensee conducts plant startup activities appropriately

through the following activities:

1. Heatup and Startup. Verify that the licensee has met TS; license conditions;

and other requirements, commitments, and administrative procedure

prerequisites for mode changes before it changes modes or plant

configurations.

Specific Guidance

(a) Review the reactor physics testing results. Verify that core operating limit

parameters are consistent with the design.

(b) Review the RCS boundary leakage calculations. Verify that the licensee

has met the TS leakage requirements before making the applicable mode

changes.

(c) Review the status of containment penetrations and containment isolation

valves. Verify that the licensee has established containment integrity

before entering the applicable TS mode.

(d) Verify that the licensee is appropriately considering and managing plant

risk.

2. Containment Closure. If containment is opened, conduct a walkdown of

containment just before closure.

Specific Guidance

During required containment walkdowns, verify the following:

(a) There is no evidence of leakage, and pay attention to areas recently

worked.

(b) There is no debris left adrift that might contribute to emergency core

cooling system sump blockage.

(c) Maintenance tags have been appropriately cleared.

(d) Passive systems have no obvious indications of damage.

71111.20-04 REFERENCES

Cross Reference of Generic Communications to IP 71111.20 and Inspection Resources:

http://nrr10.nrc.gov/rorp/ip71111-20.html

Operating Experience:

http://nrr10.nrc.gov/ope-info-gateway/index.html

IHS Codes and Standards:

http://www.internal.nrc.gov/TICS/library/standards/ihs.html

Issue Date: 11/28/17 12 71111.20

NRC Technical Library:

http://www.internal.nrc.gov/TICS/library/index.html

END

Issue Date: 11/28/17 Att 1-1 71111.20

Attachment 1 – Revision History for IP 71111.20

Commitment

Tracking

Number

Accession

Number

Issue Date

Change Notice

Description of Change Description

of Training

Required

and

Completion

Date

Comment and

Feedback

Resolution

Accession Number

(Pre-Decisional,

Non-Public

Information)

N/A 04/03/00

CN-00-003

Initial Issuance. Revision history reviewed for the last

four years

None

N/A 03/06/01

CN-01-006

Revised to clarify resource estimates for refueling,

non-refueling, and forced outages. The IP was also

revised to show the interaction between the shutdown

operations SDP and IP 71111.13, "Maintenance Risk

Assessments and Emergent Work Evaluation," in

performing risk assessments in accordance with 10 CFR 50.65(a)(4).

None

N/A 01/17/02

CN-02-001

Revised to integrate with IMC 0609, Appendix G,

"Shutdown Operations Significance Determination

Process," regarding risk insights and how to evaluate

inspection findings. It also addresses refueling

controls, improper sequencing of control rods or fuel

assemblies, reactivity control, and methods to ensure

fuel assembles are loaded in correct positions.

None

N/A ML033230221

11/05/03

CN-03-036

Revised to address licensee procedures for foreign

material exclusion, instruments tracking plant condition

changes, training procedures for BWR alternate decay

heat removal. It also cross references IMC 2515,

Appendix DProperty "Inspection Manual Chapter" (as page type) with input value "NRC Inspection Manual 2515,</br></br>Appendix D" contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process., "Plant Status" regarding plant status tours

of areas accessible only during outages.

None

N/A ML041280023

05/06/04

CN-04-011

Revised to add guidance for containment inspections,

when possible, and to add a completion status section.

None

Issue Date: 11/28/17 Att 1-2 71111.20

Commitment

Tracking

Number

Accession

Number

Issue Date

Change Notice

Description of Change Description

of Training

Required

and

Completion

Date

Comment and

Feedback

Resolution

Accession Number

(Pre-Decisional,

Non-Public

Information)

N/A ML052580099

09/02/05

CN-05-024

Revised to add the objective of evaluating licensee

activities during reduced inventory and mid-loop

conditions to ensure that they appropriately manage

risk using commitments made in response to GL 88-17

(Loss of Decay Heat Removal). The IP was also

revised to recognize that the need for containment

walkdown should factor in containment type with

regard to ALARA and heat stress.

None

NA ML080300064

01/31/08

CN-08-005

Revised as part of the 2007 ROP realignment to: (1)

clarifies when outages should be addressed via

IP 71111.20 vs IP 71153, and (2) clarifies annual

inspection resources for non-refueling and forced

outages.

Incorporated guidance regarding: (1) managing fatigue

(IP 93002), (2) containment walkthroughs, and (3)

inspection resources in accordance with the 2009 ROP

realignment. The revised inspection procedure will

take effect on January 1, 2010.

None ML080250276

NA ML092090694

11/09/09

CN 09-026

Guidance regarding (1) managing fatigue (IP 93002),

(2) containment walkthroughs, and (3) inspection

resources in accordance with the 2009 ROP

realignment.

Revised to group existing fatigue assessment

guidance into a new, separate section, and to add

IP 71111.11 as acceptable guidance to observe startup activities in the control room, based on the 2014

ROP Enhancement Project feedback.

None ML092780024

Issue Date: 11/28/17 Att 1-3 71111.20

Commitment

Tracking

Number

Accession

Number

Issue Date

Change Notice

Description of Change Description

of Training

Required

and

Completion

Date

Comment and

Feedback

Resolution

Accession Number

(Pre-Decisional,

Non-Public

Information)

NA ML15016A138

01/27/15

CN 15-001

(1) Grouped existing fatigue assessment guidance into

new, separate section; and (2) added IP 71111.11 as

acceptable guidance to observe start-up activities in

the control room (2014 ROP Enhancement Project

feedback)

None 71111.20-2046

ML15026A551

71111.20-2047

ML15026A552

71111.20-2048

ML15026A569

ML17179A651

11/28/17

CN 17-027

Added guidance to review calculations for reactor

pressure vessel water inventory control. Eliminated

redundancy and improved plain language. Relocated

optional requirements to the guidance section to better

align with the sample completion requirements in

IMC 2515, Section 08.04.

None ML17184A001

71111.20-2274

ML17205A326