NRC Inspection Manual 0609/Appendix A, The Significance Determination Process (SDP) for Findings At-Power

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The Significance Determination Process (SDP) for Findings At-Power

ML101400574

Issue Date: 06/19/12 1 0609 Appendix A Effective Date: 07/01/12 APPENDIX A

1.0 APPLICABILITY

The SDP described in this Appendix is designed to provide the staff and management with a simplified framework and associated guidance for use in screening at-power findings, directing the user to other applicable SDP appendices, and performing a detailed risk evaluation. This SDP is applicable to at-power findings within the Initiating Events, Mitigation Systems, and Barrier Integrity cornerstones.

2.0 ENTRY CONDITIONS

The SDP described in this appendix is implemented by direction from Inspection Manual Chapter (IMC) 0609, Attachment 4, “Initial Characterization of Findings.”

3.0 BACKGROUND

Over the years, maintaining the pre-solved tables and risk-informed notebooks from IMC 0609, App A proved to be a challenging task. As plants implemented equipment modifications and associated revisions to the plant risk model, the accuracy of the pre-solved tables and risk-informed notebooks began to degrade. Instead of separately maintaining and updating the plant specific pre-solved tables and risk-informed notebooks, the agency decided to transition to a software-based system called SAPHIRE (Systems Analysis Programs for Hands-on Integrated Reliability Evaluations). Using SAPHIRE a user can perform analyses on a regularly maintained site-specific Standardized Plant Assessment Risk (SPAR) model. Updating site-specific SPAR models provides an efficient and effective infrastructure that facilitates risk model fidelity. For legacy, reference, and knowledge transfer purposes, the pre-solved tables, risk-informed notebooks, and associated ROP guidance documents will be archived.

In the transition from the pre-solved tables and risk-informed notebooks to SAPHIRE and the site-specific SPAR models it is important to note process differences. The pre-solved tables and risk-informed notebooks, by process, provided a second layer of screening and an estimation of the risk impact of the finding. In lieu of the pre-solved tables and risk-informed notebooks, the SDP Workspace, a module within each SPAR model, was developed. The SDP Workspace performs a delta CDF calculation similar in many respects to the risk estimate performed by use of the risk-informed notebooks. However, use of SDP workspace is no longer intended to provide a prescriptive additional layer of screening beyond that which is outlined in section 5.0 “Screening” of this appendix. Rather, the SDP workspace is one of many tools the inspection staff and SRAs can utilize to support a detailed risk evaluation (see section 6.0 “Detailed Risk Evaluation” for more details).

4.0 SCREENING AND DETAILED RISK EVALUATION OVERVIEW

This appendix is divided into two functional parts. The first part is a screening tool that uses a series of logic questions to determine whether or not the finding can be characterized as having low safety significance (i.e., Green) and preclude a more detailed risk evaluation. The second part provides guidance in determining the risk significance of a finding that did not screen to Green in part one.

5.0 SCREENING

The screening questions are categorized by cornerstone, as such there is one set of screening questions for Initiating Events, one for Mitigating Systems, and one for Barrier Integrity (Exhibits 1, 2, and 3 respectively). If more than one cornerstone is affected, the screening questions in all the affected cornerstones apply. In addition, under each cornerstone the screening questions are categorized into sub-sections, so a finding and associated degraded condition might be applicable to more than one subsection. Typically the inspection staff completes the screening process with support from the regional SRAs, as needed. The screening questions cover a wide range of instances and scenarios, but are not intended to be all inclusive. Therefore, if the inspection staff and/or SRA do not agree with the screening results, other risk tools (e.g., the SDP workspace) and guidance provided in section 6.0 “Detailed Risk Evaluation” can be used to confirm or challenge the screening results. The screening process also directs the user to other applicable SDP appendices as needed (similar to Table 3 of IMC 0609, Attachment 4).

The screening logic questions are designed to systematically determine whether a degraded condition(s) resulting from a finding is of low safety significance (i.e., Green) or not. If all the logic questions under the applicable cornerstone(s) do not apply, then the finding is screened as Green and the risk evaluation is complete (assuming that the inspectors do not have any technical reservations with the screening results). Basically, the logic questions under a specific cornerstone are linked by a logical AND in that all the logic questions are required to be not applicable to the degraded condition(s) in order to screen as Green. Conversely, if any one of the logic questions under a specific cornerstone is applicable to the degraded condition(s), the finding cannot be screened as Green and further risk evaluation is warranted. In this case, the logic questions are linked by a logical OR in that only one of the logic questions is required to be applicable to the degraded condition to preclude screening the finding to Green.

Initiating Events

(Exhibit 1) The Initiating Events screening questions are categorized into five sub-sections titled Loss of Coolant Accident (LOCA) Initiators, Transient Initiators, Support System Initiators, Steam Generator Tube Rupture (SGTR), and External Event Initiators. Below is additional guidance to support answering the screening questions for each sub-section: LOCA Initiators – Considers small, medium, and large LOCA initiating events.

Transient Initiators – A transient initiator is an event that results in a reactor trip or scram. Some examples of transients are loss of main feedwater, loss of condenser heat sink, and loss of offsite power events.

Support System Initiators – A support system initiator involves a degraded condition of a support system that either causes an initiating event or increases the likelihood of an initiating event AND causes a degraded condition with an increase in the likelihood of a failure of one or more mitigating SSCs.

SGTR – No additional guidance External Event Initiators – In the initiating events cornerstone the external events of interest are limited to fire and internal flooding. Other external events, in the context of the initiating events cornerstone, are not applicable because the licensee does not have control over these events (e.g., tornado, hurricane). However, the licensee does have control over the systems used to mitigate an external event and that is covered in the

Mitigating Systems section

(Exhibit 2). Mitigating Systems (Exhibit 2) The Mitigating Systems screening questions are categorized into four sub-sections titled Mitigating Systems, Structures, Components (SSCs) and Functionality (except Reactivity Control Systems), External Event Mitigation Systems (Seismic/Fire/Flood/Severe Weather Protection Degraded), Reactivity Control Systems, and Fire Brigade. Below is additional guidance to support answering the screening questions for each sub-section: Mitigating SSCs and Functionality (except Reactivity Control Systems) – For the purposes of this subsection, the SSCs (and their associated functions) of concern are those that provide a risk significant or risk relevant mitigating function in response to an initiating event. Normally those SSCs that are in the risk model provide a risk significant or risk relevant function; however that is not always the case (e.g., some SSCs are not modeled explicitly). There are several ways to determine whether an SSC provides a risk significant or risk relevant mitigating function and below are some sources of information to support this determination:

1) Plant Risk Information eBook (PRIB) (Table 6) – Table lists systems/functions that are included in the SPAR model. It also provides specific success criteria given a particular initiating event. See PRIB definition in section 6.0 “Detailed Risk Evaluation”.
2) PRIB (Table 7) – Table lists the components included in the SPAR model with their associated risk importance measures.
3) SDP Workspace – The SDP workspace contains risk significant and risk relevant SSCs derived from the specific SPAR model.
4) UFSAR – Although the systems/function described in the UFSAR might be different than the systems/function modeled in the SPAR, the licensed design bases for systems/functions can provide useful information in determining safety significance.
5) Licensee Risk Insights – If provided, risk insights from the licensee risk model (e.g., importance measures, dominant sequences, delta CDF calculations, etc) and risk/safety significant SSCs from their maintenance rule program can be a good source of risk information.

External Event Mitigation Systems (Seismic/Fire/Flood/Severe Weather Protection Degraded) – No additional guidance Reactivity Control Systems – Reactor Protection System (RPS) – The main focus of the screening question is to screen findings that result in a minor functional degradation of RPS (e.g., one automatic trip from one instrument) but there are several redundant trips that provide the same function (e.g., three other automatic functional trips). If there is a significant functional degradation to RPS, a detailed risk evaluation is warranted. The determination of what a “significant” or “minor” functional degradation of RPS should be based on reasonable technical judgment of the inspectors, SRA, and management. Fire Brigade – No additional guidance

Barrier Integrity

(Exhibit 3) The Barrier Integrity screening questions are categorized into four sub-sections titled RCS Boundary, Reactor Containment, Control Room/Auxiliary/Reactor Building or Spent Fuel Pool Building, and Spent Fuel Pool. Below is additional guidance to support answering the screening questions for each sub-section: RCS Boundary – Pressurized thermal shock issues are addressed under the barrier integrity cornerstone. All other RCS boundary issues (i.e., leakage) are evaluated under the initiating events cornerstone.

Reactor Containment – No additional guidance

Control Room/Auxiliary/Reactor Building or Spent Fuel Pool Building – No additional guidance

Spent Fuel Pool – No additional guidance

6.0 DETAILED RISK EVALUATION

The inspection staff and regional SRAs should coordinate efforts, using their specific skills, training, and qualifications, to arrive at an appropriate risk evaluation given the specific circumstances associated with the risk impact of the degraded condition(s) that resulted from the finding. Typically inspectors develop the finding and the associated functional impact on the equipment and gather plant information to support the detailed risk evaluation. Then the inspectors and SRA collaborate to develop appropriate input assumptions while the SRA normally performs the detailed risk evaluation for greater than green findings using the SPAR model, the RASP handbooks, and other risk information as necessary. When the internal events detailed risk evaluation results are greater than or equal to 1.0E-7, the finding should be evaluated for external event risk contribution. Any internal events results that are less than 1.0E-7 can be evaluated for external event risk contribution at the discretion of the regional SRA. If an inspector uses the SDP Workspace to perform a detailed risk evaluation, a regional SRA should review the results to determine if any additional analyses need to be performed. If more than one cornerstone is affected by the finding and associated degraded condition(s), the risk evaluation of the finding should take into account all of the associated degraded condition(s) from all of the affected cornerstones. However, for the purposes of the power reactor assessment program, the cornerstone which captures the majority fraction of the overall risk evaluation should be identified as the affected cornerstone. The risk tools and guidance available to the staff to perform the detailed risk evaluation are discussed below: SAPHIRE and SPAR Models

1) SDP Workspace – The SDP Workspace provides the user with a delta CDF (and delta LERF) calculation with a comprehensive report of results. This tool only accounts for risk associated with internal events (i.e., does not account for external event risk contributions) and cannot be adjusted to change the model (e.g., recovery actions, common cause failure).
2) Event Condition Assessment – A workspace that is used by the SRA that allows the analyst more flexibility in adjusting basic events.
3) General Analysis – A workspace that is used by the SRA that allows more flexibility in adjusting both basic events and model logic.
4) Specific SPAR Model Changes – The SRA can alter the SPAR model logic and create a set of changed basic events to reflect the degraded condition(s) and/or event. This approach provides the most flexibility in performing a delta CDF calculation.
5) Plant Risk Information eBook (PRIB) – The PRIB is a summary document associated with the site-specific SPAR model that provides a variety of risk insights.

Changes to SAPHIRE and SPAR Models

NOTE: The risk tools (e.g., SDP workspace) and guidance to support the SDP are designed to have users engaged in the process and avoid a “blackbox” approach in determining the risk significance of deficient licensee performance. Users need to be aware of the limitations and specific capabilities of each risk tool and associated guidance to preclude misapplication.

Identified Errors or Discrepancies – Identified errors or discrepancies with SAPHIRE or the site-specific SPAR model should be discussed and vetted by the inspection staff and SRA and then reported to INL via the SAPHIRE webpage at https://saphire.inl.gov/. On the SAPHIRE webpage there is one module to request changes to SAPHIRE (i.e., software) and a separate module to request changes to the SPAR models (which includes changes to the PRIB). Timely SDP Evaluations – To support the SDP timeliness goal, a SRA may make changes to the SPAR model of record, as appropriate, based on information from the inspectors and/or the licensee, to accurately reflect the risk significance of the finding. These changes must be documented in the associated inspection report and/or SERP package. The SRA should subsequently review the model changes made to determine if those model changes should be incorporated into the plant SPAR model of record. Guidance

1) RASP Handbooks – Volume 1 (Internal Events), 2 (External Events), and Volume 4 (Shutdown) - These handbooks provide standardized risk guidance and best practices to support determinations across a variety of NRC programs (SDP, Accident Sequence Precursor (ASP), and Management Directive (MD) 8.3 “Event Evaluation”) 2) NUREGs – There are many NUREGs that can provide useful information when performing a detailed risk evaluation (e.g., initiating event and failure data, common cause failure modeling techniques). END


Exhibit 1 - Initiating Events Screening Questions Exhibit 2 - Mitigating Systems Screening Questions Exhibit 3 - Barrier Integrity Screening Questions Exhibit 4 - External Events Screening Questions

Exhibit 1 - Initiating Events Screening Questions

A. LOCA Initiators

1. After a reasonable assessment of degradation, could the finding result in exceeding the RCS leak rate for a small LOCA?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, continue.

2. After a reasonable assessment of degradation, could the finding have likely affected other systems used to mitigate a LOCA resulting in a total loss of their function (e.g., Interfacing System LOCA)?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green.

B. Transient Initiators

Did the finding cause a reactor trip AND the loss of mitigation equipment relied upon to transition the plant from the onset of the trip to a stable shutdown condition (e.g. loss of condenser, loss of feedwater)? Other events include high energy line-breaks, internal flooding, and fire.

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green.

C. Support System Initiators

Did the finding involve the complete or partial loss of a support system that contributes to the likelihood of, or cause, an initiating event AND affected mitigation equipment? Examples of support system initiators are loss of offsite power (LOOP), Loss of a DC Bus, Loss of an AC Bus, Loss of Component Cooling Water (LCCW), Loss of Service Water (LOSW), and Loss of Instrument Air (LOIA).

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green.

D. Steam Generator Tube Rupture

1. Does the finding involve a degraded steam generator tube condition where one tube cannot sustain 3 times the differential pressure across a tube during normal full power, steady state operation (3ΔPNO)?

a. If YES ➛Stop. Go to IMC 0609, Appendix J.
b. If NO, continue.

2. Does one or more SGs violate “accident leakage” performance criterion (i.e., involve degradation that would exceed the accident leakage performance criterion under design basis accident conditions).

a. If YES ➛Stop. Go to Detailed Risk Evaluation section and refer to IMC 0609, Appendix J as applicable.
b. If NO, screen as Green.

E. External Event Initiators

Does the finding impact the frequency of a fire or internal flooding initiating event?

a. If YES ➛ Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green.

Exhibit 2 – Mitigating Systems Screening Questions

A. Mitigating SSCs and Functionality

(except Reactivity Control Systems – see section C below) 1. If the finding is a deficiency affecting the design or qualification of a mitigating SSC, does the SSC maintain its operability or functionality?

If YES ➛Screen as Green.
b. If NO, continue.

2. Does the finding represent a loss of system and/or function?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, continue.

3. Does the finding represent an actual loss of function of at least a single Train for > its Tech Spec Allowed Outage Time OR two separate safety systems out-of-service for > its Tech Spec Allowed Outage Time?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, continue.

4. Does the finding represent an actual loss of function of one or more non-Tech Spec Trains of equipment designated as high safety-significant in accordance with the licensee’s maintenance rule program for >24 hrs?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green.

B. Does the finding involve the loss or degradation of equipment or function specifically designed to mitigate a seismic, flooding, or severe weather initiating event (e.g., seismic snubbers, flooding barriers, tornado doors)? External Event Mitigation Systems (Seismic/Fire/Flood/Severe Weather Protection Degraded)

a. If YES ➛Go to Exhibit 4
b. If NO ➛screen as Green

C. Reactivity Control Systems

1. Did the finding affect a single reactor protection system (RPS) trip signal to initiate a reactor scram AND the function of other redundant trips or diverse methods of reactor shutdown (e.g., other automatic RPS trips, alternate rod insertion, or manual reactor trip capacity)?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, continue.

2. Did the finding involve control manipulations that unintentionally added positive reactivity (e.g., inadvertent boron dilution, cold water injection, inadvertent control rod movement, recirculation pump speed control)?

a. If YES, ➛Stop. Go to IMC 0609, Appendix M
b. If NO, continue

3. Did the finding result in a mismanagement of reactivity by operator(s) (e.g., reactor power exceeding the licensed power limit, inability to anticipate and control changes in reactivity during crew operations)?

a. If YES, ➛Stop. Go to IMC 0609, Appendix M
b. If NO, screen as Green

D. Fire Brigade

1. Does the finding involve Fire Brigade training and qualification requirements, or brigade staffing?

a. If YES ➛check if one or more of the following apply:
The fire brigade demonstrated the ability to meet the required times for fire extinguishment for the fire drill scenarios, and the finding did not significantly affect the ability of the fire brigades to respond to a fire.
The overall time duration (exposure time) that the Fire Brigade was understaffed was short (< 2 hours).
b. If at least one of the above is checked ➛screen as Green.
c. If NO, continue

2. Does the finding involve the response time of the fire brigade to a fire?

a. If YES ➛check if one or more of the following apply:
The fire brigade’s response time was mitigated by other defense-in-depth elements, such as area combustible loading limits were not exceeded, installed fire detection systems were functional, and alternate means of safe shutdown were not impacted.
The finding involved risk-significant fire areas that had automatic suppression systems.
The licensee had adequate Fire Protection compensatory actions in place.
b. If at least one of the above is checked ➛screen as Green.
If NO, continue

3. Does the finding involve fire extinguishers, fire hoses, or fire hose stations?

a. If YES ➛check if one or more of the following apply:
There was no degraded fire barrier and the fire scenario did not require the use of water to extinguish the fire.
The missing fire extinguisher or fire hose was missing for a short time and other extinguishers or hose stations were in the vicinity.
b. If at least one of the above is checked ➛screen as Green.
c. If none of the boxes under D.1.a, D.2.a, or D.3.a are checked ➛Stop. Go to IMC 0609, Appendix M.

Exhibit 3 – Barrier Integrity Screening Questions

A. RCS Boundary

(e.g., pressurized thermal shock issues)

Stop. Go to Detailed Risk Evaluation section.

B. Reactor Containment:

1. Does the finding represent an actual open pathway in the physical integrity of reactor containment (valves, airlocks, etc), containment isolation system (logic and instrumentation), and heat removal components?

a. If YES ➛ Stop. Go to IMC 0609, Appendix H.
b. If NO, continue.

2. Does the finding involve an actual reduction in function of hydrogen igniters in the reactor containment?

a. If YES ➛ Stop. Go to IMC 0609, Appendix H.
b. If NO, screen as Green.

C. Control Room, Auxiliary, Reactor, or Spent Fuel Pool Building:

1. Does the finding only represent a degradation of the radiological barrier function provided for the control room, or auxiliary building, or spent fuel pool, or SBGT system (BWR)?

a. If YES ➛ Stop. screen as Green.
b. If NO, continue.

2. Does the finding represent a degradation of the barrier function of the control room against smoke or a toxic atmosphere?

a. If YES ➛ Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green

D. Spent Fuel Pool (SFP)

1. Does the finding adversely affect decay heat removal capabilities from the spent fuel pool causing the pool temperature to exceed the maximum analyzed temperature limit specified

in the site-specific licensing basis?

a. If YES ➛ Stop. Go to IMC 0609, Appendix M.
b. If NO, continue.

2. Does the finding result from fuel handling errors, dropped fuel assembly, dropped storage cask, or crane operations over the SFP that caused mechanical damage to fuel clad AND a detectible release of radionuclides?

a. If YES ➛ Stop. Go to IMC 0609, Appendix M (refer to IMC 0609, Appendix C as applicable).
b. If NO, continue.

3. Does the finding result in a loss of spent fuel pool water inventory decreasing below the minimum analyzed level limit specified in the site-specific licensing basis?

a. If YES ➛ Stop. Go to IMC 0609, Appendix M.
b. If NO, continue.

4. Does the finding affect the SFP neutron absorber, fuel bundle misplacement (i.e., fuel loading pattern error) or soluble Boron concentration (PWRs only)?

a. If YES ➛ Stop. Go to IMC 0609, Appendix M.
b. If NO, screen as Green.

Exhibit 4 – External Events Screening Questions

1. If the equipment or safety function is assumed to be completely failed or unavailable, are ANY of the following three statements TRUE? The loss of this equipment or function by itself during the external initiating event it was intended to mitigate:

would cause a plant trip or an initiating event
would degrade two or more trains of a multi-train system or function;
would degrade one or more trains of a system that supports a risk significant system or function.
a. If YES ➛STOP. Go to Detailed Risk Evaluation section.
b. If NO, Continue.

2. Does the finding involve the total loss of any safety function, identified by the licensee through a PRA, IPEEE, or similar analysis, that contributes to external event initiated core damage accident sequences (i.e., initiated by a seismic, flooding, or severe weather event)?

a. If YES ➛Stop. Go to Detailed Risk Evaluation section.
b. If NO, screen as Green

Attachment 1 – Revision History for IMC 0609 Appendix A

Commitment Tracking Number Accession Number Issue Date Change Notice Description of Change Training Required and Completion Date Comment and Feedback Resolution Accession Number Issue Date: 06/19/12 Att 1-2 0609 Appendix A Effective Date: 07/01/12 Commitment Tracking Number Accession Number Issue Date Change Notice Description of Change Training Required and Completion Date Comment and Feedback Resolution Accession Number 04/21/00 CN 00-007 Initial issue 12/28/00 CN 00-029 Revised to incorporate changes based on inspector feedback. Enhancements generated by IIPB and SPSB risk analysts based on initial implementation experience to date have also been added. A significant change is the credit given for operator actions in step 2.3 of the document. Clarification changes have also been made to the phase 1 screening worksheets. Phase 2 worksheets are in the process of being updated to include plant and site specific information. This document is an integral part of the Significant Determination Process for reactor inspection findings for At-Power operations and will be used by resident and region-based inspectors as well as by SRAs. 02/05/01 CN 01-003 Revised to correct formatting problems with charts and tables, and to make minor editorial changes. 03/18/02 CN 02-009 Revised: 1) to correct identified problems with the appendix, 2) to incorporate the rules for using the site specific risk-informed inspection notebook, 3) to simplify the process of accounting for external initiators in characterizing the risk significant inspection

Commitment Tracking Number Accession Number Issue Date Change Notice Description of Change Training Required and Completion Date Comment and Feedback Resolution Accession Number findings, and 4) to provide guidance on evaluating concurrent inspection findings. ML042600558 09/10/04 CN 04-023 Multiple editorial changes to enhance user friendliness of the document. For example, re-format action steps, provided additional examples, added the reference to Appendix J for steam generator issues. N/A ML043560116 12/01/04 CN 04-027 Corrected two errors on page 4 of the worksheet, under MS cornerstone for screening issues and under BI cornerstone guidance for question 3 for screening to Green. N/A ML052790196 11/22/05 CN 05-030 Enhanced guidance to help meet timeliness requirements for finalizing the SDP for inspection findings. N/A ML063470288 03/23/07 CN 07-011 Incorporate references to the site-specific inspection notebooks and associated Pre-Solved Tables; In Attachment 2, update the site specific risk-informed inspection notebooks usage rules; Attachment 3, provide user guidance for screening of external events risk contributions. 1. Training has been provided to the SRAs at last two SRA counterpart meetings, and the SRAs have provided training to the region based and resident inspectors (10/2006) 2. Formalized training will be introduced through the P-111 course (FY 2008) ML070720624 ML063060377 Removed the Phase 1 Initial Screening and N/A ML073460588 Issue Date: 06/19/12 Att 1-4 0609 Appendix A Effective Date: 07/01/12 Commitment Tracking Number Accession Number Issue Date Change Notice Description of Change Training Required and Completion Date Comment and Feedback Resolution Accession Number 01/10/08 CN 08-002 Characterization of Findings process to create the new IMC 0609, Attachment 4. Added clarification statement to Step 2.1.2 and Usage Rule 1.1 that the maximum exposure time used in SDP is limited to one year. ML101400574 06/19/12 CN 12-010 Updated the guidance to reflect the transition from the pre-solved tables and risk-informed notebooks to SAPHIRE and the site-specific SPAR models. Moved the Initiating Events, Mitigating Systems, and Barrier Integrity screening questions from IMC 0609, Attachment 4 to this appendix. Incorporated feedback from ROPFFs 0609.04-1458 and 0609A-1575. This is a complete reissue. Senior Reactor Analysts and headquarters staff provided detailed instructor-led training to resident inspectors, region based inspectors, and other regional staff. June 2012 ML12142A091 Closed FBF: 0609.04-1458 ML12171A225 0609A-1575 ML12171A231

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