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Notice

Notice of Availability of Model Application Concerning Technical Specification Improvement To Extend the Completion Times for Inoperable Containment Isolation Valves at General Electric Plants Using the Consolidated Line Item Improvement Process

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AGENCY:

Nuclear Regulatory Commission.

ACTION:

Notice of Availability.

SUMMARY:

Notice is hereby given that the staff of the Nuclear Regulatory Commission (NRC) has prepared a model application relating to changes to the Standard Technical Specifications (STSs) 3.6.1.3, “Primary Containment Isolation Valves (PCIVs),” for boiling-water reactors (BWR) in NUREG-1433, Revision 3, “Standard Technical Specifications, General Electric Plants, BWR/4,” and “NUREG-1434, Revision 3, “Standard Technical Specifications, General Electric Plants, BWR/6.” The proposed change to the STSs 3.6.1.3 would extend to 7 days the completion time (CT) (or allowed outage time (AOT)) to restore an inoperable PCIV to operable status or isolate the affected penetration flow path both for selected primary containment penetrations with two (or more) PCIVs and for selected primary containment penetrations with only one PCIV. This change is based on analyses provided in a generic topical report (TR) submitted by the BWR Owners' Group (BWROG). The BWROG, through its participation in the Technical Specification (TS) Task Force (TSTF) proposed this change to the STSs in Change Traveler No. TSTF-454, Revision 1. This notice also includes a model safety evaluation (SE) and a model no significant hazards consideration (NSHC) determination relating to this matter.

The purpose of these models is to permit the NRC to efficiently process amendments to incorporate this change into plant-specific TSs for General Electric (GE) BWRs. Licensees of nuclear power reactors to which the models apply can request amendments conforming to the models. In such a request, a licensee should provide supporting documentation to confirm the applicability of the SE and NSHC determination to its plant.

DATES:

The NRC staff issued a Federal Register Notice (70 FR 30151, May 25, 2005) which provided a model SE and a model NSHC determination relating to the extension of the CT for TS actions related to inoperable PCIVs at GE plants. The NRC staff hereby announces that the model SE and NSHC determination may be referenced in plant-specific applications to extend the PCIV completion times as described in Revision 1 to TSTF-454. The staff has posted a model application on the NRC Web site to assist licensees in using the consolidated line item improvement process (CLIIP) to request the subject TS change. The NRC staff can most efficiently consider applications based upon the model application if the application is submitted within a year of this Federal Register Notice.

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FOR FURTHER INFORMATION CONTACT:

Bhalchandra Vaidya, Mail Stop: O-7D1, Division of Operating Reactor Licensing, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone (301) 415-3308.

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SUPPLEMENTARY INFORMATION:

Background

Regulatory Issue Summary 2000-06, “Consolidated Line Item Improvement Process for Adopting Standard Technical Specifications Changes for Power Reactors,” was issued on March 20, 2000. The CLIIP is intended to improve the efficiency and transparency of NRC licensing processes. This is accomplished by processing proposed changes to the STSs in a manner that supports subsequent license amendment applications. The CLIIP includes an opportunity for the public to comment on proposed changes to the STSs, following a preliminary assessment by the NRC staff, and finding that the change will likely be offered for adoption by licensees. The CLIIP directs the NRC staff to evaluate any comments received for a proposed change to the STSs and to either reconsider the change or proceed with announcing the availability of the change for proposed adoption by licensees. Those licensees opting to apply for the subject change to TSs are responsible for reviewing the staff's evaluation, referencing the applicable technical justifications, and providing any necessary plant-specific information. Each amendment application made in response to the notice of availability would be processed and noticed in accordance with applicable NRC rules and procedures.

This notice involves an increase in the allowed CTs to restore an inoperable PCIV to operable status or isolate the affected penetration flow path when selected PCIVs are inoperable at BWRs. By letter dated September 5, 2003, the BWROG proposed this change, including corresponding changes to the TS Bases, for incorporation into the STSs as TSTF-454, Revision 0. By letter dated September 21, 2005, BWROG revised the proposed change as TSTF-454, Revision 1. This change is based on the NRC staff-approved generic analyses contained in BWROG TR NEDC-33046-A, “Technical Justification to Support Risk-Informed Primary Containment Isolation Valve AOT Extensions for BWR Plants,” transmitted to the NRC on January 20, 2005, which is accessible electronically from the Agencywide Documents Access and Management System's (ADAMS) Public Electronic Reading Room on the Internet (ADAMS Accession No. ML050240360) at the NRC Web site http://www.nrc.gov/​reading-rm/​adams.html. This transmittal incorporated TR NEDC-33046, submitted on May 3, 2002 (ADAMS Accession No. ML021280156), as supplemented by letter dated July 30, 2003 (ADAMS Accession No. ML032130164), and as approved by the NRC in its letter and SE dated October 8, 2004 (ADAMS Accession No. ML042660055). Persons who do not have access to ADAMS or who encounter problems in accessing the documents located in ADAMS, should contact the NRC Public Document Room Reference staff by telephone at 1-800-397-4209, 301-415-4737, or by e-mail to pdr@nrc.gov.

Applicability

This proposed change to revise the TS CTs for selected PCIVs is applicable to GE BWRs.

To efficiently process the incoming license amendment applications, the NRC staff requests each licensee applying for the changes addressed by TSTF-454, Revision 1, to use the CLIIP to address the seven plant-specific conditions and the one commitment identified in the model SE, as follows: Start Printed Page 73803

Conditions

1. Because not all penetrations have the same impact on core damage frequency (CDF), large early release frequency (LERF), incremental conditional core damage probability (ICCDP), or incremental conditional large early release probability (ICLERP), a licensee's application must provide supporting information that verifies the applicability of TR NEDC-33046, including verification that the PCIV configurations for the specific plant match the TR and that the risk parameter values used in the TR are bounding for the specific plant. Any additional PCIV configurations or non-bounding risk parameter values not evaluated by the TR should be included in the licensee's plant-specific analysis. [Note that PCIV configurations or non-bounding risk parameter values outside the scope of the TR will require NRC staff review of the specific penetrations and related justifications for the proposed CTs.]

2. The licensee's application must provide supporting information that verifies that external event risk, either through quantitative or qualitative evaluation, will not have an adverse impact on the conclusions of the plant-specific analysis for extending the PCIV CTs.

3. Because TR NEDC-33046 was based on generic plant characteristics, each licensee adopting the TR must provide supporting information that confirms plant-specific Tier 3 information in their individual submittals. The licensee's application must provide supporting information that discusses conformance to the requirements of the maintenance rule (10 CFR 50.65(a)(4)), as they relate to the proposed PCIV CTs and the guidance contained in NUMARC 93-01, Section 11, as endorsed by Regulatory Guide (RG) 1.182, “Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants.” This should include verification that the licensee's maintenance rule program, with respect to PCIVs, includes a LERF and ICLERP assessment as part of the maintenance rule process.

4. The licensee's application must provide supporting information that verifies that a penetration remains intact during maintenance activities, including corrective maintenance activities. Regarding maintenance activities where the pressure boundary would be broken, the licensee must provide supporting information that confirms that the assumptions and results of the TR remain valid. This includes the assumption that maintenance on a PCIV will not break the pressure boundary for more than the currently allowed CT.

5. The licensee's application must provide supporting information that it will verify the operability of the remaining PCIVs in the associated penetration flow path before applying an extended CT for an inoperable PCIV.

6. Simultaneously utilizing the proposed extended CT for multiple inoperable PCIVs and the resulting impact on risk were not specifically evaluated by the BWROG. However, TR NEDC-33046 does state that multiple PCIVs can be out of service simultaneously during extended CTs and does not preclude the practice. Therefore, the licensee's application must provide supporting information that confirms that its Tier 3 configuration risk management program (10 CFR 50.65(a)(4)) requires that simultaneous application of an extended CT to more than one inoperable PCIV in separate penetration flow paths is evaluated. The purpose of this evaluation is to ensure that the cumulative risk of continued plant operation with multiple inoperable PCIVs utilizing extended CTs does not exceed the plant risk value, as determined by the analysis presented in TR NEDC-33046.

7. The licensee must provide supporting information that verifies that the plant-specific probabilistic risk assessment (PRA) quality is acceptable for this application in accordance with the guidelines given in RG 1.174, “An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-specific Changes to the Licensing Basis.” To ensure the applicability of TR NEDC-33046 to a licensee's plant, each licensee requesting an amendment must provide additional information on PRA quality in the following areas:

a. Justification that the plant-specific PRA reflects the as-built, as-operated plant.

b. Applicable PRA updates including individual plant examinations (IPE) and individual plant examinations of external events (IPEEE) findings.

c. Conclusions of the peer review including any A or B facts and observations (F and Os) applicable to the proposed PCIV extended CTs.

d. The PRA quality assurance program and associated procedures.

e. PRA adequacy, completeness, and applicability with respect to evaluating the plant specific impact of the proposed PCIV extended CT.

Commitment

The RG 1.177, “An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications,” Tier 3 program ensures that, while the plant is in a limiting condition for operation (LCO) actions condition with an extended CT for restoring an inoperable PCIV to operable status, additional activities will not be performed that could further degrade the capabilities of the plant to respond to a condition the inoperable PCIV or associated system is designed to mitigate and, as a result, increase plant risk beyond that determined by the TR analysis. A licensee's implementation of RG 1.177 Tier 3 guidelines generally implies the assessment of risk with respect to CDF. However, the proposed PCIV extended CT impacts containment isolation and, consequently, LERF as well as CDF. Therefore, each licensee requesting extended CTs for PCIVs under TSTF-454, Revision 1, must commit to enhancing its configuration risk management program (CRMP), including those implemented under 10 CFR 50.65(a)(4), the maintenance rule, to include a LERF methodology and assessment. This commitment and the CRMP enhancements must be documented in the licensee's plant-specific application.

The CLIIP does not prevent licensees from requesting an alternative approach or proposing the changes without providing the information described in the above seven conditions, or making the requested commitment. Variations from the approach recommended in this notice may, however, require additional review by the NRC staff and may increase the time and resources needed for the review.

Public Notices

In a notice published in the Federal Register dated May 25, 2005 (70 FR 30151), the NRC staff requested comment on the use of the CLIIP to process requests to extend the CT for selected inoperable PCIVs at GE plants, as described in Revision 0 of TSTF-454.

TSTF-454, Revision 1, as well as the NRC staff's SE and model application, may be examined, and/or copied for a fee, at the NRC's Public Document Room, located at One White Flint North, Public File Area O-1 F21, 11555 Rockville Pike (first floor), Rockville, Maryland. Publicly available records are accessible electronically from the ADAMS Public Library component on the NRC Web site, (the Electronic Reading Room).

In response to the notice soliciting comments from interested members of the public about modifying the TS requirements regarding an increase in the specified CTs to restore an inoperable PCIV to operable status or Start Printed Page 73804isolate the affected penetration flow path when selected PCIVs are inoperable at BWRs, the NRC staff received three comments from the Owners Group TSTF members. These comments were specific to the model SE and are discussed as follows:

Comment 1 (as stated)

Condition 3, Condition 6, and the one required commitment of Section 3.2, Evaluation of Proposed Changes, of the model Safety Evaluation are not clear or consistent on the expectations for a containment performance assessment (i.e., large early release fraction [should be “frequency”], or LERF) as part of the configuration risk management program (CRMP). These conditions should be clarified either in the Safety Evaluation or in the CLIIP model application.

Condition 3 requires licensees to conform to the Maintenance Rule requirements of 10 CFR 50.65(a)(4), as it relates to Primary Containment Isolation Valve (PCIV) Completion Times and the guidance of NUMARC 93-01, “Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants,” Section 11, including a LERF and incremental conditional large early release probability (ICLERP) assessment as part of the process. In addition, Condition 6 requires the CRMP to confirm that simultaneous extended Completion Time entries in separate penetration flow paths will not exceed the Regulatory Guide 1.174 and Regulatory Guide 1.177 acceptance guidelines. The commitment required by the Safety Evaluation also requires the licensee's CRMP be enhanced to include a LERF methodology and assessment.

Many licensees do not currently have a probabilistic risk assessment (PRA) Level 2 model built into the CRMP for calculating a LERF risk value. Adding the LERF model will significantly delay adoption of the proposed Traveler [TSTF-454]. The containment risk management assessment is routinely addressed through qualitative methods and administrative controls. Section 11 of NUMARC 93-01 allows for qualitative assessment methods. Section 11.3.4, Assessment Methods for Power Operating Conditions, states, “Simultaneous removal from service of multiple SSCs [structures, systems, and components] requires that an assessment be performed using quantitative, qualitative, or blended (quantitative and qualitative) methods.” Sections 11.3.4.1 and 11.3.4.2 provide guidance regarding quantitative and qualitative considerations, respectively.

Is it the intent of the conditions and commitment to require a PRA calculation to quantify LERF risk values for the specific plant configurations each time a PCIV is inoperable? Would this apply only when the extended Completion Time is used or only when multiple penetration flow paths are affected as discussed in Condition 6? Would it be acceptable to assess and manage the containment performance impacts by qualitative methods and administrative controls as currently allowed by NUMARC 93-01 as endorsed by Regulatory Guide 1.182? For example, an assessment program could manage containment performance risk by limiting the number of affected penetration flow paths depending on factors such as the flow path size and not require a LERF calculation for each occurrence.

Response to Comment 1

The BWROG states that many licensee's do not have a level 2 PRA model built into the CRMP for calculating LERF. The BWROG further states that adopting a LERF model will significantly delay implementation of the proposed TSTF traveler. The BWROG references Sections 11.3.4.1 and 11.3.4.2 of NUMARC 93-01 for both quantitative and qualitative risk assessment methods in the evaluation of Tier 3. Although they are inter-related, the following questions were identified in BWROG Comment 1 concerning Conditions 3 and 6 of the staff model SE issued for comment on May 25, 2005 (70 FR 30151).

1. Is it the intent of the conditions and commitment to require a PRA calculation to quantify the LERF risk values for the specific plant configurations each time a PCIV is inoperable?

2. Would this apply only when the extended CT is used or only when multiple penetration flow paths are effected as discussed in Condition 6?

3. Would it be acceptable to assess and manage the containment performance impacts by qualitative methods and administrative controls as currently allowed by NUMARC 93-01, endorsed by RG 1.182?

Condition 3 of the model SE is intended to ensure that a licensee's CRMP includes a LERF and an ICLERP assessment for PCIVs as part of the CRMP and maintenance rule process. The intent of the conditions and commitment is to ensure an assessment of risk for the actual resulting plant configuration when a PCIV is inoperable. The concerns of the NRC staff are that PCIVs affect risk mainly through LERF, and that CRMP evaluations performed as part of Tier 3 may not address LERF in the risk evaluation. An additional concern of the NRC staff stems from the fact that TR NEDC-33046 only evaluated the risk of extending the CT for a single PCIV. However, the implementation of the TR allows separate concurrent extended CTs for multiple inoperable PCIVs because the current and proposed STSs for extended PCIVs allow separate actions condition entry for each penetration flow path (see the NRC staff's response to Comment 2). As stated by the BWROG in its comment, many licensees do not have a PRA level 2 model incorporated into the CRMP for the evaluation of LERF. The intent of Condition 3 is to ensure that Tier 3 evaluations of both CDF and LERF are performed to assess PCIV CTs when PCIVs are determined to be inoperable or taken out of service. As stated in Condition 3 of the NRC staff model SE, a licensee's application must provide supporting information that discusses the plant's conformance to the requirements of the maintenance rule (10 CFR 50.65(a)(4)) and the guidance contained in NUMARC 93-01, Section 11, as endorsed by RG 1.182. With respect to comment 1 in general, the NRC staff cannot provide a definitive response without reviewing a plant-specific approach. The assessment program chosen by a licensee or the BWROG (qualitative, quantitative, or combination) must be documented in the licensee's application because Tier 3 aspects of the proposed PCIV CT extensions were not specifically addressed by TR NEDC-33046. Therefore, the NRC staff does not believe that changes to Condition 3 are warranted.

Comment 2 (as Stated)

Condition 6 of Section 3.2, Evaluation of Proposed Changes, requires the licensee's application to provide supporting information that verifies that the potential for any cumulative risk impact of failed PCIVs and multiple PCIV extended Completion Time entries has been evaluated and is acceptable. The verb tense “has been evaluated” is confusing. Is [it] the intent to require an assessment of the plant's design and historical experience to verify that the potential for multiple extended Completion Time entries is low? Please clarify either in the Safety Evaluation or in the CLIIP model application what the evaluation involves.

Response to Comment 2

The following question was identified in BWROG Comment 2 concerning Condition 6 of the staff model SE issued for comment on May 25, 2005 (70 FR 30151).

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The verb tense “has been evaluated” is confusing. Is [it] the intent of condition 6 to require an assessment of the plant's design and historical experience to verify that the potential for multiple concurrent use of extended Completion Times is low? Please clarify in either the Safety Evaluation or the CLIIP model application what the assessment should address.

Condition 6 is concerned with the Tier 3 analysis that provides added assurance that the TR's conclusion that no risk significant configurations will result from the proposed extended PCIV CTs remains valid over extended periods of plant operation. However, in addition to Condition 6, as stated in the NRC staff's TR SE, a licensee adopting TR NEDC-33046 must confirm that the conclusions of the generic Tier 2 analysis are applicable to its facility.

As already stated, TR NEDC-33046 does not limit the number of PCIVs that can concurrently but separately be in an actions condition with an extended CT because the PCIV TS actions allow separate condition entry for each penetration flow path. The intent of Condition 6 is to ensure that, for multiple concurrently inoperable PCIVs, including those utilizing extended CTs, the licensee will evaluate the impact on risk to verify that the conditions of TR NEDC-33046 remain satisfied. As stated in Condition 3 of the NRC staff's model SE, a licensee's application to adopt TSTF-454, Revision 1, must provide supporting information that discusses the plant's CRMP and inoperable PCIV assessment program, the plant's conformance to the requirements of the maintenance rule (10 CFR 50.65(a)(4)), and the guidance contained in NUMARC 93-01, Section 11, as endorsed by RG 1.182 for the assessment of risk, including LERF and ICLERP resulting from PCIV maintenance.

Based on the above, the staff will revise Condition 6 of the model SE to clarify the applicability to Tier 3 CRMP as follows:

(6) Simultaneously utilizing the proposed extended CT for multiple inoperable PCIVs and the resulting impact on risk were not specifically evaluated by the BWROG. However, TR NEDC-33046 does state that multiple PCIVs can be out of service simultaneously during extended CTs and does not preclude the practice. Therefore, the licensee's application must provide supporting information that confirms that its Tier 3 configuration risk management program (10 CFR 50.65(a)(4)) requires that simultaneous application of an extended CT to more than one inoperable PCIV in separate penetration flow paths is evaluated. The purpose of this evaluation is to ensure that the cumulative risk of continued plant operation with multiple inoperable PCIVs utilizing extended CTs does not exceed the plant risk value, as determined by the analysis presented in TR NEDC-33046.

Comment 3 (as stated)

Condition 1 of Section 3.2, Evaluation of Proposed Changes, uses the terms “incremental conditional core damage frequency (ICCDP)” and “incremental conditional large early release frequency (ICLERP).” The word “frequency” in these two terms should be changed to “probability.”

Response to Comment 3

The staff agrees. The editorial errors for definitions of incremental conditional core damage frequency (ICCDP) and incremental conditional large early release frequency (ICLERP) will be corrected in the model SE.

Other Changes to the Notice of Opportunity To Comment, Published in the Federal Register Dated May 25, 2005 (70 FR 30151)

In addition to the changes mentioned in the above discussion of comments, editorial changes, such as consistent use of “TR” in place of “LTR,” use of “CT” in place of “AOT,” etc., have been made without altering the original intent to the Notice of Opportunity for Comments published in the Federal Register dated May 25, 2005 (70 FR 30151).

As described in the model application prepared by the NRC staff, licensees may reference in their plant-specific applications for adopting this change to STSs, the model SE, model NSHC determination, and the environmental consideration in this “Notice of Availability” published in the Federal Register.

Model Safety Evaluation

U.S. Nuclear Regulatory Commission; Office of Nuclear Reactor Regulation

Consolidated Line Item Improvement

Technical Specification Task Force (TSTF) Change; Traveler No. TSTF-454, Revision 1, “Extend PCIV Completion Times (NEDC-33046)”

1.0 Introduction

By application dated [ ], [Licensee] (the licensee) requested changes to the Technical Specifications (TSs) for [facility]. The proposed changes would revise TS 3.6.1.3, “Primary Containment Isolation Valves (PCIVs),” by extending to 7 days the completion time (CT) to restore an inoperable PCIV to operable status or to isolate the affected penetration flow path for selected primary containment penetrations with two (or more) PCIVs and for selected primary containment penetrations with only one PCIV.

2.0 Regulatory Evaluation

The existing Limiting Condition for Operation (LCO) 3.6.1.3, requires that each PCIV be operable. The operability of PCIVs ensures that the containment is isolated during a design-basis accident (DBA) and is able to perform its function as a barrier to the release of radioactive material. For boiling water reactor (BWR)/4 plants, if a PCIV is inoperable in one or more penetrations, the current required action is to isolate or restore the inoperable PCIV to operable status within 4 hours for penetrations with 2 PCIVs (except for the main steam line, in which case 8 hours is allowed), and within 4 hours for penetrations with a single PCIV (except for excess flow check valves (EFCVs) and penetrations with a closed system, and for other cases if justified with a plant-specific evaluation, in which case 72 hours is allowed). Regarding the leakage rate of EFCVs, 72 hours is also currently allowed to restore EFCV leakage to within limit. For BWR/6 plants, the current required actions are the same as those for the BWR/4 plants, with the exception that there are no TSs for EFCVs. The times specified for performing these actions were considered reasonable, given the time required to isolate the penetration and the relative importance of ensuring containment integrity during plant operation. In the case of a single EFCV PCIV or a single PCIV and a closed system, the specified CT takes into consideration the ability of the instrument and the small pipe diameter (associated with the EFCV) or the closed system to act as a penetration boundary.

On May 3, 2002, as supplemented by letter dated July 30, 2003, the BWR Owners Group (BWROG) submitted the generic Topical Report (TR) NEDC-33046, “Technical Justification to Support Risk-Informed Primary Containment Isolation Valve AOT [Allowed Outage Time] Extensions for BWR Plants,” which provided a risk-informed justification for extending the TS AOT (also referred to as CT), for a specific set of inoperable PCIVs from the current 4 hours or 72 hours to 7 days. Specifically, for BWR/4 plants, if a PCIV is inoperable in one or more penetrations, the proposed action is to isolate or restore the inoperable PCIV to operable status within 7 days for penetrations with 2 PCIVs (except for the feedwater isolation valves (FWIVs) and the residual heat removal (RHR) shutdown cooling suction line PCIVs, in which case the 4 hours is kept, and except for the main steam line isolation valves (MSIVs), in which case the 8 hours is kept) and within 4 hours for Start Printed Page 73806penetrations with a single PCIV, except for EFCVs and penetrations with a closed system, in which case 7 days is allowed (and except for other cases if justified with a plant-specific evaluation, in which case the 72 hours is kept). Regarding the leakage rate of EFCVs, 7 days is also proposed to restore EFCV leakage to within the limit. For BWR/6 plants, the proposed actions are the same as those for the BWR/4 plants with the exception that for penetrations with 2 PCIVs, there is an additional exception to the 7-day CT (for the low pressure core spray system PCIVs, in which case the 4 hours is kept); and with the exception that there are no TSs for EFCVs.

The NRC staff used the guidance of Regulatory Guide (RG) 1.174, “An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Current Licensing Basis, November 2002” and RG 1.177, “An Approach for Plant-Specific, Risk-Informed Decision Making: Technical Specifications, August 1998,” in performing its review of this TR. RG 1.174 provides the guidelines to determine the risk associated with the proposed change. RG 1.177 provides a three-tiered approach to evaluate the risks associated with proposed license amendments. The first tier evaluates the probabilistic risk assessment (PRA) model and the impacts of the changes on plant operational risk. The second tier addresses the need to preclude potentially high risk configurations, should additional equipment outages occur during the CT. The third tier evaluates the licensee's configuration risk management program (CRMP) to ensure that the removal of equipment from service immediately prior to or during the proposed CT will be appropriately assessed from a risk perspective. The NRC staff's safety evaluation (SE) dated October 8, 2004, also discusses the applicable regulations and additional applicable regulatory criteria and guidelines that were considered in its review of TR NEDC-33046. By letter dated January 20, 2005, BWROG transmitted TR NEDC-33046-A to NRC, which incorporated the TR NEDC-33046, submitted on May 3, 2002, as supplemented by letter dated July 30, 2003, and as approved by the NRC in a letter and SE dated October 8, 2004.

3.0 Technical Evaluation

3.1 Statement of Proposed Changes

The proposed changes to STS 3.6.1.3 for BWR/4 and BWR/6 plants, as approved in TSTF-454, Revision 1, include:

1. For the Condition of one or more penetration flow paths with one PCIV inoperable in a penetration flow path with two [or more] PCIVs, the Completion Times for isolating the affected penetration (in Standard Technical Specification (STS) 3.6.1.3 Required Action A.1) are revised from “4 hours except for main steam line AND 8 hours for main steam line,” to “4 hours [for feedwater isolation valves (FWIVs), residual heat removal (RHR) shutdown cooling suction line PCIVs, and Low Pressure Core Spray (LPCS) System PCIVs (NUREG-1434 only)] AND 8 hours for main steam line isolation valves (MSIVs) [AND 7 days except for FWIVs, RHR shutdown cooling suction line PCIVs, LPCS System PCIVs (NUREG-1434 only), and MSIVs.]” For PCIVs not analyzed in NEDC-33046-A (i.e., FWIVs and MSIVs), the current Completion Times of 4 hours and 8 hours of STS 3.6.1.3 Required Action A.1 are maintained; 4 hours for FWIVs and 8 hours for main steam lines (i.e., MSIVs as described in the current Bases for STS 3.6.1.3 Required Action A.1). For PCIVs analyzed in NEDC-33046-A that did not meet the criterion for extension (i.e., RHR shutdown cooling suction line PCIVs (for all BWRs) and LPCS System PCIVs (for BWR/5 and BWR/6 designs only)), the current Completion Time of 4 hours of STS 3.6.1.3 Required Action A.1 is maintained. The Completion Time for other PCIVs, associated with penetrations with two [or more] PCIVs, is extended to 7 days.

2. For the Condition of one or more penetration flow paths with one PCIV inoperable in a penetration flow path with only one PCIV, the Completion Times for isolating the affected penetrations (STS 3.6.1.3, Required Action C.1) are revised from “[4] hours except for excess flow check valves (EFCVs) and penetrations with a closed system AND [72] hours for EFCVs and penetrations with a closed system,” to “[4] hours except for excess flow check valves (EFCVs) and penetrations with a closed system AND [7days] for EFCVs and penetrations with a closed system.” (For NUREG-1434, the Completion Times for STS 3.6.1.3, Required Action C.1 are revised from “[4] hours except for penetrations with a closed system AND [72] hours for penetrations with a closed system,” to “[4] hours except for penetrations with a closed system AND [7days] for penetrations with a closed system.”)

3. For the Condition of one or more [secondary containment bypass leakage rate,] [MSIV leakage rate,] [purge valves leakage rate,] [hydrostatically tested line leakage rate,] [or] [EFCV leakage rate] not within limit, for NUREG-1433, the Completion Time for restoring leakage rate to within limit, when the leakage rate exceeded is the EFCV leakage rate (in STS 3.6.1.3 Required Action D.1), is revised from “[72 hours for hydrostatically tested line leakage [on a closed system] [and EFCV leakage]]” to “[72 hours for hydrostatically tested line leakage [on a closed system] [AND 7 days for EFCV leakage].” (The EFCV leakage rate Completion Time change is not applicable to NUREG-1434.)

3.2 Evaluation of Proposed Changes

The NRC staff's SE on TR NEDC-33046, dated October 8, 2004, found that, based on the use of bounding risk parameters for General Electric (GE)-designed plants, for the proposed increase in the PCIV CT from 4 hours (for penetrations with 2 or more PCIVs) or 72 hours (for penetrations with a single EFCV PCIV, and penetrations with a single PCIV and a closed system) or 72 hours (for EFCV leakage) to 7 days, the risk impact of the proposed 7-day CT for the PCIVs, as estimated by core damage frequency (CDF), large early release frequency (LERF), incremental conditional core damage probability (ICCDP), and incremental conditional large early release probability (ICLERP), is consistent with the acceptance guidelines specified in RG 1.174, RG 1.177, and NRC staff guidance outlined in Chapter 16.1 of NUREG-0800, “Standard Review Plan.” The NRC staff found that the risk analysis methodology and approach used by the BWROG to estimate the risk impacts were reasonable and of sufficient quality. The NRC staff's October 8, 2004, SE also found the following:

The Tier 2 evaluation did not identify any risk-significant plant equipment configurations requiring TSs, procedure, or compensatory measures. TR NEDC-33046 implements a CRMP (Tier 3) using 10 CFR 50.65(a)(4) to manage plant risk when PCIVs are taken out-of-service. PCIV reliability and availability will also be monitored and assessed under the maintenance rule (10 CFR 50.65) to confirm that performance continues to be consistent with the analysis assumptions used to justify extended PCIVs CTs.

3.2.1 Conditions and Commitment

The NRC staff's October 8, 2004, SE also found that certain conditions and a commitment must be addressed by licensees adopting TR NEDC-33046 (or TR NEDC-33046-A transmitted to NRC by letter dated January 20, 2005) in plant-specific applications. These conditions and the commitment, as clarified herein, that must be addressed Start Printed Page 73807by licensees adopting TR NEDC-33046-A in plant-specific applications that seek approval of TSTF-454, Revision 1, for their plants, are as follows:

3.2.1.1 Conditions

1. Because not all penetrations have the same impact on CDF, LERF, ICCDP, or ICLERP, a licensee's application must provide supporting information that verifies the applicability of TR NEDC-33046, including verification that the PCIV configurations for the specific plant match the TR and that the risk parameter values used in the TR are bounding for the specific plant. Any additional PCIV configurations or non-bounding risk parameter values not evaluated by the TR should be included in the licensee's plant-specific analysis. [Note that PCIV configurations or non-bounding risk parameter values outside the scope of the TR will require NRC staff review of the specific penetrations and related justifications for the proposed CTs.]

2. The licensee's application must provide supporting information that verifies that external event risk, either through quantitative or qualitative evaluation, will not have an adverse impact on the conclusions of the plant-specific analysis for extending the PCIV CTs.

3. Because TR NEDC-33046 was based on generic plant characteristics, each licensee adopting the TR must provide supporting information that confirms plant-specific Tier 3 information in their individual submittals. The licensee's application must provide supporting information that discusses conformance to the requirements of the maintenance rule (10 CFR 50.65(a)(4)), as they relate to the proposed PCIV CTs and the guidance contained in NUMARC 93-01, Section 11, as endorsed by RG 1.182, “Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants.” This should include verification that the licensee's maintenance rule program, with respect to PCIVs, includes a LERF and ICLERP assessment as part of the maintenance rule process.

4. The licensee's application must provide supporting information that verifies that a penetration remains intact during maintenance activities, including corrective maintenance activities. Regarding maintenance activities where the pressure boundary would be broken, the licensee must provide supporting information that confirms that the assumptions and results of the TR remain valid. This includes the assumption that maintenance on a PCIV will not break the pressure boundary for more than the currently allowed CT.

5. The licensee's application must provide supporting information that it will verify the operability of the remaining PCIVs in the associated penetration flow path before applying an extended CT for an inoperable PCIV.

6. Simultaneously utilizing the proposed extended CT for multiple inoperable PCIVs and the resulting impact on risk were not specifically evaluated by the BWROG. However, TR NEDC-33046 does state that multiple PCIVs can be out of service simultaneously during extended CTs and does not preclude the practice. Therefore, the licensee's application must provide supporting information that confirms that its Tier 3 CRMP (10 CFR 50.65(a)(4)) requires that simultaneous application of an extended CT to more than one inoperable PCIV in separate penetration flow paths is evaluated. The purpose of this evaluation is to ensure that the cumulative risk of continued plant operation with multiple inoperable PCIVs utilizing extended CTs does not exceed the plant risk value, as determined by the analysis presented in TR NEDC-33046.

7. The licensee must provide supporting information that verifies that the plant-specific probabilistic risk assessment (PRA) quality is acceptable for this application in accordance with the guidelines given in RG 1.174, “An Approach for using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-specific Changes to the Licensing Basis.” To ensure the applicability of TR NEDC-33046 to a licensee's plant, each licensee requesting an amendment must provide additional information on PRA quality in the following areas:

a. Justification that the plant-specific PRA reflects the as-built, as-operated plant.

b. Applicable PRA updates including individual plant examinations (IPE) and individual plant examinations of external events (IPEEE) findings.

c. Conclusions of the peer review including any A or B facts and observations (F and Os) applicable to the proposed PCIV extended CTs.

d. The PRA quality assurance program and associated procedures.

e. PRA adequacy, completeness, and applicability with respect to evaluating the plant specific impact of the proposed PCIV extended CT.

3.2.1.2 Commitment

The RG 1.177 Tier 3 program ensures that, while the plant is in a LCO actions condition with an extended CT for restoring an inoperable PCIV to operable status, additional activities will not be performed that could further degrade the capabilities of the plant to respond to a condition the inoperable PCIV or associated system is designed to mitigate and, as a result, increase plant risk beyond that determined by the TR analysis. A licensee's implementation of RG 1.177 Tier 3 guidelines generally implies the assessment of risk with respect to CDF. However, the proposed PCIV extended CT impacts containment isolation and, consequently, LERF as well as CDF. Therefore, each licensee requesting extended CTs for PCIVs under TSTF-454, Revision 1, must commit to enhancing its CRMP, including those implemented under 10 CFR 50.65(a)(4), the maintenance rule, to include a LERF methodology and assessment. This commitment and the CRMP enhancements must be documented in the licensee's plant-specific application.

3.3 Staff Findings

The NRC staff has reviewed the proposed TS changes and finds that they are consistent with previous staff reviews of TR NEDC-33046, submitted by letter dated May 3, 2002, as supplemented by letter dated July 30, 2003, and as approved by the NRC by letter and SE dated October 8, 2004, which are incorporated in TR NEDC-33046-A, transmitted to NRC by letter dated January 20, 2005, and TSTF-454, Revision 1, and are acceptable. The NRC staff has also reviewed the licensee's supporting information and the statements regarding the above conditions and commitment and finds them acceptable. Therefore, the NRC staff finds that the increase in the CTs from 4 hours (for penetrations with 2 or more PCIVs) or 72 hours (for penetrations with a single EFCV PCIV, and penetrations with a single PCIV and a closed system) or 72 hours (for EFCV leakage) to 7 days is justified.

4.0 Regulatory Commitment

The licensee's letter dated [   ], contained the following regulatory commitment: [state the licensee's commitment and ensure that it satisfies the commitment in this SE, in section 3.2 above.]

The NRC staff finds that reasonable controls for the implementation and for subsequent evaluation of proposed changes pertaining to the above regulatory commitment are best provided by the licensee's administrative processes, including its commitment management program. The above regulatory commitment does not warrant the creation of a license condition (item requiring prior NRC approval of subsequent changes). Start Printed Page 73808

5.0 State Consultation

In accordance with the Commission's regulations, the [State] State official was notified of the proposed issuance of the amendments. The State official had [Choose one: (1) No comments, OR (2) The following comments—with subsequent disposition by the staff].

6.0 Environmental Consideration

The amendment changes a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts and no significant change in the types of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding ([XX FR XXXXX, dated Month DD, YYYY]). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

7.0 Conclusion

The Commission has concluded, based on the considerations discussed above, that: (1) There is reasonable assurance that the health and safety of the public will not be endangered by the operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Model No Significant Hazards Consideration Determination

Description of Amendment Request: The proposed amendment extends the completion time (CT) for penetration flow paths with one valve inoperable from 4 hours or 72 hours to 7 days. The change is applicable to both primary containment penetrations with two (or more) primary containment isolation valves (PCIVs) and with one PCIV. This change is not applicable to the feedwater isolation valves (FWIVs), the residual heat removal (RHR) shutdown cooling suction line PCIVs, the low pressure core spray (LPCS) PCIVs (boiling water reactor (BWR)/6 only), the main steam isolation valves (MSIVs), and [list of plant-specific valves].

Basis for proposed no significant hazards consideration determination: As required by 10 CFR 50.91(a), an analysis of the issue of no significant hazards consideration is presented below:

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

The proposed change revises the completion times (CTs) for restoring an inoperable primary containment isolation valve (PCIV) (or isolating the affected penetration) within the scope of the Boiling Water Reactor (BWR) Owners Group (BWROG) Topical Report (TR) NEDC-33046-A, “Technical Justification to Support Risk-Informed Primary Containment Isolation Valve AOT [Allowed Outage Time] Extensions for BWR Plants,” transmitted to NRC by letter dated January 20, 2005, from 4 hours and 72 hours to 7 days. PCIVs are not accident initiators in any accident previously evaluated. Consequently, the probability of an accident previously evaluated is not significantly increased.

PCIVs, individually and in combination, control the extent of leakage from the primary containment following an accident. As such, PCIVs are instrumental in controlling the consequences of an accident. However, the consequences of any accident previously evaluated are no different during the proposed extended CTs than during the existing CTs. As a result, there would be no significant increase in the consequences of an accident previously evaluated. Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated. The proposed changes revise the CTs for restoring an inoperable PCIV or isolating the affected penetration within the scope of NEDC-33046-A, transmitted to NRC by letter dated January 20, 2005, from 4 hours and 72 hours to 7 days. PCIVs, individually and in combination, control the extent of leakage from the primary containment following an accident. The proposed CT extensions apply to the reduction in redundancy in the primary containment isolation function by the PCIVs for a limited period of time, but do not alter the ability of the plant to meet the overall primary containment leakage requirements. The proposed change does not alter the design, configuration, or method of operation of the plant. The proposed change does not involve a physical alteration of the plant and no new or different type of equipment will be installed. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

The proposed change does not involve a significant reduction in a margin of safety. The proposed change revises the CTs for restoring an inoperable PCIV or isolating the affected penetration within the scope of the NEDC-33046-A, transmitted to NRC by letter dated January 20, 2005, from 4 hours and 72 hours to 7 days. PCIVs, individually and in combination, control the extent of leakage from the primary containment following an accident. The proposed CT extensions apply to the reduction in redundancy in the primary containment isolation function provided by the PCIVs for a limited period of time, but do not alter the ability of the plant to meet the overall primary containment leakage requirements. In order to evaluate the proposed CT extensions, a PRA evaluation was performed in TR NEDC-33046 submitted on May 3, 2002, as supplemented by letter dated July 30, 2003, and as approved by the NRC by letter and SE dated October 8, 2004. The PRA evaluation concluded that, based on the use of bounding risk parameters for GE-designed plants, the proposed increase in the PCIV CTs from 4 hours or 72 hours to 7 days does not alter the ability of the plant to meet the overall primary containment leakage requirements. It also concluded that the proposed changes do not result in an unacceptable ICCDP or ICLERP according to the guidelines of RG 1.177. Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and accordingly, a finding of “no significant hazards consideration” is justified.

Start Signature

Dated at Rockville, Maryland, this 4th day of December, 2005.

Start Printed Page 73809

For the Nuclear Regulatory Commission.

David Terao,

Chief, Plant Licensing Branch G, Division of Operating Reactor Licensing, Office of Nuclear Reactor Regulation.

End Signature End Supplemental Information

[FR Doc. E5-7272 Filed 12-12-05; 8:45 am]

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