ML043420026

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License Amendments 215 and 220, Increased Flexibility in Mode Restraints
ML043420026
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 12/22/2004
From: Chernoff H
NRC/NRR/DLPM/LPD3
To: Koehl D
Nuclear Management Co
Chernoff, H, NRR/DLPM, 301-415-4018
Shared Package
ML043420030 List:
References
TAC MC1713, TAC MC1714
Download: ML043420026 (25)
v • d • e


Text

December 22, 2004 Dennis Koehl Site Vice President Point Beach Nuclear Plant Nuclear Management Company, LLC 6610 Nuclear Road Two Rivers, WI 54241-9516

SUBJECT:

POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 - ISSUANCE OF AMENDMENTS RE: INCREASED FLEXIBILITY IN MODE RESTRAINTS (TAC NOS. MC1713 AND MC1714)

Dear Mr. Koehl:

The Commission has issued the enclosed Amendment No. 215 to Facility Operating License No. DPR-24 and Amendment No. 220 to Facility Operating License No. DPR-27 for the Point Beach Nuclear Plant, Units 1 and 2, respectively. The amendments consist of changes to the Technical Specifications (TS) in response to your application dated December 23, 2003.

The amendments modify TS requirements to adopt the provisions of Industry/TS Task Force (TSTF) change TSTF-359, Increased Flexibility in Mode Restraints. The availability of TSTF-359 for adoption by licensees was announced in the Federal Register on April 4, 2003 (68 FR 16579).

A copy of our related safety evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.

Sincerely,

/RA/

Harold K. Chernoff, Project Manager, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-266 and 50-301

Enclosures:

1. Amendment No. 215 to DPR-24
2. Amendment No. 220 to DPR-27
3. Safety Evaluation cc w/encls: See next page

Point Beach Nuclear Plant, Units 1 and 2 cc:

Jonathan Rogoff, Esquire Mr. Jeffery Kitsembel Vice President, Counsel & Secretary Electric Division Nuclear Management Company, LLC Public Service Commission of Wisconsin 700 First Street P.O. Box 7854 Hudson, WI 54016 Madison, WI 53707-7854 Mr. F. D. Kuester Nuclear Asset Manager President & Chief Executive Officer Wisconsin Electric Power Company WE Generation 231 West Michigan Street 231 West Michigan Street Milwaukee, WI 53201 Milwaukee, WI 53201 John Paul Cowan Regulatory Affairs Manager Executive Vice President & Chief Nuclear Point Beach Nuclear Plant Officer Nuclear Management Company, LLC Nuclear Management Company, LLC 6610 Nuclear Road 700 First Street Two Rivers, WI 54241 Hudson, WI 54016 Mr. Ken Duveneck Douglas E. Cooper Town Chairman Senior Vice President - Group Operations Town of Two Creeks Palisades Nuclear Plant 13017 State Highway 42 Nuclear Management Company, LLC Mishicot, WI 54228 27780 Blue Star Memorial Highway Covert, MI 49043 Chairman Public Service Commission Site Director of Operations of Wisconsin Nuclear Management Company, LLC P.O. Box 7854 6610 Nuclear Road Madison, WI 53707-7854 Two Rivers, WI 54241 Regional Administrator, Region III U.S. Nuclear Regulatory Commission 801 Warrenville Road Lisle, IL 60532-4351 Resident Inspector's Office U.S. Nuclear Regulatory Commission 6612 Nuclear Road Two Rivers, WI 54241 January 2003

ML043420026 ADAMS Accession No.: ML043420030 (Package) ADAMS Accession No.: ML043650312 (TS) NRR-058 OFFICE PDIII-1/PM CLIIP LPM PDIII-1/PM PDIII-1/LA IROB OGC PDIII-1/(A)SC NAME LPadovan WReckley HChernoff DClarke TBoyce AOH MKotzalas DATE 12/10/04 12/10/04 12/10/04 12/09/04 12/15/04 12/20/04 12/22/04 NUCLEAR MANAGEMENT COMPANY, LLC DOCKET NO. 50-266 POINT BEACH NUCLEAR PLANT, UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 215 License No. DPR-24

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Nuclear Management Company, LLC (the licensee), dated December 23, 2003, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Facility Operating License No. DPR-24 is hereby amended to read as follows:

B. Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 215, are hereby incorporated in the license. The licensee shall operate the facility in accordance with Technical Specifications.

3. This license amendment is effective as of the date of issuance and shall be implemented within 120 days of the date of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

L. Raghavan, Chief, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of issuance: December 22, 2004

NUCLEAR MANAGEMENT COMPANY, LLC DOCKET NO. 50-301 POINT BEACH NUCLEAR PLANT, UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 220 License No. DPR-27

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Nuclear Management Company, LLC (the licensee), dated December 23, 2003, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Facility Operating License No. DPR-27 is hereby amended to read as follows:

B. Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 220, are hereby incorporated in the license. The licensee shall operate the facility in accordance with Technical Specifications.

3. This license amendment is effective as of the date of issuance and shall be implemented within 120 days of the date of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

L. Raghavan, Chief, Section 1 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of issuance: December 22, 2004

ATTACHMENT TO LICENSE AMENDMENT NO. 215 TO FACILITY OPERATING LICENSE NO. DPR-24 AND LICENSE AMENDMENT NO. 220 TO FACILITY OPERATING LICENSE NO. DPR-27 DOCKET NOS. 50-266 AND 50-301 Replace the following pages of the Appendix A Technical Specifications with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

REMOVE INSERT 3.0-1 3.0-1 3.0-2 3.0-2 3.0-3 3.0-3 3.0-4 3.0-4 3.0-5 3.0-5 3.3.3-1 3.3.3-1 3.4.11-1 3.4.11-1 3.4.12-1 3.4.12-1 3.4.15-1 3.4.15-1 3.4.15-2 3.4.15-2 3.4.16-1 3.4.16-1 3.5.3-1 3.5.3-1 3.7.4-1 3.7.4-1 3.7.5-1 3.7.5-1 3.8.1-1 3.8.1-1 3.8.1-2 3.8.1-2

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 215 TO FACILITY OPERATING LICENSE NO. DPR-24 AND AMENDMENT NO. 220 TO FACILITY OPERATING LICENSE NO. DPR-27 NUCLEAR MANAGEMENT COMPANY, LLC POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 DOCKET NOS. 50-266 AND 50-301

1.0 INTRODUCTION

Nuclear Management Company, LLCs (NMCs or licensees), application of December 23, 2003, requested changes to the Technical Specifications (TSs) for the Point Beach Nuclear Plant, Units 1 and 2. The requested changes would modify TS requirements for mode change limitations in Limiting Condition for Operation (LCO) 3.0.4 and Surveillance Requirement (SR) 3.0.4 to adopt the provisions of Industry/TS Task Force (TSTF) change TSTF-359, Increased Flexibility in Mode Restraints. The availability of TSTF-359 for adoption by licensees was announced in the Federal Register on April 4, 2003 (68 FR 16579). NMC included minor variations from the TSTF-359 wording to reflect plant-specific terminology, numbering, and configuration.

On July 17, 2002, the Nuclear Energy Institute (NEI) Risk Informed TS Task Force (RITSTF) submitted proposed change, TSTF-359, Revision 7, to the Standard TS (STS)

(NUREGs 1430-1434) on behalf of the industry. TSTF-359, Revision 7, proposed to change the STS LCO 3.0.4 and SR 3.0.4 requirements regarding mode change limitations by risk-informing limitations on entering the mode of applicability of an LCO. The Notice of Opportunity to Comment on the model safety evaluation (SE) using the Consolidated Line Item Improvement Process with respect to this change was published in the Federal Register on August 2, 2002 (67 FR 50475). The U.S. Nuclear Regulatory Commission (NRC or the Commission) staff prepared a model SE incorporating changes resulting from public comments.

The NRC staff has since made minor editorial changes to the SE. TSTF-359, Revision 8, as modified, provides the complete approved change as discussed in the Federal Register Notice dated April 4, 2003 (68 FR 16579). The RITSTF subsequently incorporated the modifications identified in the April 4, 2003, Notice into TSTF-359, Revision 9.

This proposal is one of the industrys initiatives under the risk-informed TS program. These initiatives are intended to maintain or improve safety while reducing unnecessary burden. They also make TS requirements consistent with the NRCs other risk-informed regulatory requirements, in particular 50.65 of Title 10 of the Code of Federal Regulations (10 CFR),

Requirements for monitoring the effectiveness of maintenance at nuclear power plants, or the maintenance rule.

The current TS specify that a nuclear power plant cannot go to higher modes of operation1 (i.e., move toward power operation) unless all TS systems normally required for the higher mode are operable. This limitation is included (with several exceptions for some plants) in LCO 3.0.4 and SR 3.0.4. LCO 3.0.4 and SR 3.0.4 in the STS currently state, in part, that when an LCO or SR is not met, entry into a MODE or other specified condition in the Applicability shall not be made except when the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time. The industry believes that this requirement is unnecessarily restrictive and can unduly delay plant startup while considerable resources are being used to resolve startup issues that are risk insignificant or low risk. A maintenance activity that takes longer than planned can delay a mode change and adversely impact a utilitys orderly plant startup and return to power operation. The objective of the proposed change is to provide additional operational flexibility without compromising plant safety.

The proposed changes to LCO 3.0.4 and SR 3.0.4 would allow, for systems and components, mode changes into a TS condition that has a specific required action and completion time (CT).

The licensee will use the LCO 3.0.4 and SR 3.0.4 allowances only when it determines that there is a high likelihood that the LCO will be satisfied within the LCO CT, after the mode change. In addition, the LCO 3.0.4 and SR 3.0.4 allowances can be applied to values and parameters in specifications when explicitly stated in the TS (non-system/component TS such as Reactor Coolant System Specific Activity). These changes are in addition to the current mode change allowance when a required action has an indefinite CT. The LCO 3.0.4 and SR 3.0.4 mode change allowances are not permitted for the systems and components (termed higher risk) listed below in Section 3.1.2, Identification of Risk-Important TS Systems and Components, for the modes specified. Two examples are as follows:

  • Westinghouse plants cannot transition from Mode 5 to Mode 4 without a high-head safety injection system train operable.

2.0 REGULATORY EVALUATION

In 10 CFR 50.36, Technical specifications, the NRC established its regulatory requirements related to the content of TS. Pursuant to 10 CFR 50.36, TS are required to include items in the following five specific categories related to station operation:

  • safety limits, limiting safety system settings, and limiting control settings
  • LCOs
  • SRs
  • design features 1

MODE numbers decrease in the transition up to a higher mode of operation; power operation is MODE 1.

  • administrative controls The regulation does not specify the particular requirements to be included in the plant TS. As stated in 10 CFR 50.36(c)(2)(i), the Limiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a limiting condition for operation of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the technical specifications... By convention, the LCOs and related SRs are contained in Sections 3.1 through 3.10 of the TS. STS Section 3.0 on LCO and SR Applicability gives details or ground rules for complying with the LCOs and related SRs. LCO 3.0.4 and SR 3.0.4 address requirements for LCO compliance when transitioning between modes of operation.

TS have taken advantage of risk technology as experience and capability have increased.

Since the mid-1980's, the NRC has been reviewing and granting improvements to the TS that are based, at least in part, on probabilistic risk assessment (PRA) insights. In its final policy statement on TS improvements of July 22, 1993, the Commission stated that it expects that licensees will use any plant-specific PRA or risk survey in preparing their TS-related submittals.

In evaluating these submittals, the NRC staff applies the guidance in Regulatory Guide (RG) 1.174, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis, dated July 1998 and in RG 1.177, An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications, dated August 1998. The NRC staff has appropriately adapted this guidance to assess the acceptability of upward mode changes with equipment inoperable. This review had the following objectives:

C To ensure that the plant risk does not increase unacceptably during the actual implementation of the proposed change (e.g., when the plant enters a higher mode while an LCO is not met). This risk increase is referred to as temporary.

C To compare and assess the risk impact of the proposed change to the acceptance guidelines of the Commissions Safety Goal Policy Statement, as documented in RG 1.174. The risk impact, which is measured by the average yearly risk increase associated with the change, aims at minimizing the cumulative risk associated with the proposed change so that the plants average baseline risk is maintained within a minimal range.

C To assess the licensees ability to identify risk-significant configurations resulting from maintenance or other operational activities and take appropriate compensatory measures to avoid such configurations.

The NRC staff reviewed the reliance on 10 CFR 50.65(a)(4) for the non-higher-risk systems and components, and related guidance to assess and manage the risk of upward mode changes. The Commission has found that complying with the industry guidance for implementation of 10 CFR 50.65(a)(4), as endorsed by RG 1.182, Assessing and Managing Risk before Maintenance Activities at Nuclear Power Plants, and mandated by LCO 3.0.4, SR 3.0.4, and SR 3.0.3, satisfies the configuration risk management objectives of RG 1.177 for TS surveillance interval and CT extensions. Reliance on 10 CFR 50.65(a)(4) processes that are consistent with the provisions of the NRC-endorsed industry guidance were also found adequate for managing risk of missed surveillances as described in the Federal Register on

September 28, 2001 (66 FR 49714).

The NRC staff review also had the objective of ensuring that existing inspection programs have the necessary controls in place to allow the NRC staff to oversee the implementation of the proposed change and reliance on 10 CFR 50.65(a)(4) processes or programs. The inspection program also allows the NRC staff to adequately assess the licensees performance associated with risk assessments. The NRC review encompassed the following:

  • NRC inspection procedure (IP) 62709 dated December 28, 2000, Configuration Risk Assessment and Risk Management Process, and IP 71111.13 dated January 17, 2002, Maintenance Risk Assessments and Emergent Work Control
  • enforcement guidance in draft Enforcement Manual Section 8.1.11, Actions Involving the Maintenance Rule
  • the associated reactor oversight process (ROP).

2.1 Proposed Changes to LCO 3.0.4 and SR 3.0.4 Currently, LCO 3.0.4 does not allow entrance into a higher mode (or other specified condition) in the Applicability when an LCO is not met, except when the associated actions to be entered permit continued operation in that mode or condition indefinitely or a specific exception is granted. Similarly, when the LCO surveillances have not been met within their specified frequency, entry into a higher mode (or other specified condition) is not allowed by SR 3.0.4.

The current STS2 LCO 3.0.4 reads as follows:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall not be made except when the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time. This LCO 3.0.4 Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

Exceptions to this Specification are stated in the individual Specifications.

LCO 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

2 Plant-specific wording for current equivalent LCO 3.0.4 is similar to current STS LCO 3.0.4 wording.

NMCs revised LCO 3.0.4 will read as follows:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall only be made:

a. When the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time;
b. After performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate; exceptions to this Specification are stated in the individual Specifications, or
c. When an allowance is stated in the individual value, parameter, or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

The current STS3 SR 3.0.4 reads as follows:

Entry into a MODE or other specified condition in the Applicability of an LCO shall not be made unless the LCOs Surveillances have been met within their specified frequency.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

SR 3.0.4 is only applicable for entry into a MODE or other specified conditions in the Applicability in MODES 1, 2, 3, and 4.

NMCs revised SR 3.0.4 will conform to the changes to LCO 3.0.4 and read as follows:

Entry into a MODE or other specified condition in the Applicability of an LCO shall only be made when the LCO's Surveillances have been met within their specified Frequency, except as provided by SR 3.0.3.

When an LCO is not met due to Surveillances not having been met, entry into a MODE or other specified condition in the Applicability shall only be made in accordance with LCO 3.0.4.

3 Plant-specific wording for current equivalent SR 3.0.4 is similar to current STS SR 3.0.4 wording.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

NMCs proposed LCO 3.0.4.a retains the current allowance for when the required actions permit indefinite operation. Proposed LCO 3.0.4.b allows entering modes or other specified conditions in the Applicability, except when higher-risk systems and components (listed in Section 3.1.2) for the mode being entered are inoperable. The decision for entering a higher mode or condition in the Applicability of the LCO will be made by plant management after the required risk assessment has been performed and requisite risk management actions established through the program established to implement 10 CFR 50.65(a)(4). Entry into the modes or other specified conditions in the Applicability of the TS shall be for no more than the duration of the applicable required actions CT, or until the LCO is met. Current notes in individual specifications that permitted mode changes are now encompassed by LCO 3.0.4.b and can be removed. Notes that prohibit mode changes under LCO 3.0.4.b must be added (i.e., for higher-risk systems and components).

The proposed LCO 3.0.4.b allowance can involve multiple components in a single LCO or in multiple LCOs. However, use of the LCO 3.0.4.b provisions are always contingent upon completion of a 10 CFR 50.65(a)(4)-based risk assessment.

The current STS LCO 3.0.4 and STS SR 3.0.4 include notes limiting the applicability of those provisions to Modes 1, 2, 3, and 4, for pressurized-water reactors (PWRs). The notes limiting the applicability of LCO 3.0.4 and SR 3.0.4 are no longer needed and are removed by TSTF-359, Revision 9. Industry owners-group (Boiling-Water Reactors (BWRs) Owners Group, Babcock & Wilcox Owners Group, Combustion Engineers Owners Group (CEOG), and Westinghouse Owners Group (WOG)) analyses would subsequently support adding notes to various TS, as defined by the tables of higher-risk systems, precluding entry into Modes 5 and 6 for PWRs, and Modes 4 and 5 for BWRs. However, the addition of notes in these cases is made unnecessary by action statements that require immediate CTs, which means that entry into the Mode or other specified condition in the Applicability is not allowed and the notes would be superfluous.

LCO 3.0.4 allowances related to values and parameters of TS are not typically addressed by LCO 3.0.4.b risk assessments, and are, therefore, addressed by a new 3.0.4.c. LCO 3.0.4.c refers to allowances already in the TS and annotated in the individual specifications.

LCO 3.0.4.c also allows for entry into the modes or other specified conditions in the applicability of a TS for no more than the duration of the applicable required actions CT or until the LCO is met or the unit is not within the applicability of the TS.

3.0 TECHNICAL EVALUATION

During the development of the current STS, improvements were made to LCO 3.0.4, such as clarifying its applicability with respect to plant shutdowns, cold shutdown mode, and refueling mode. In addition, during the STS development, almost all the LCOs with CTs greater than or equal to 30 days, and many LCOs with CTs greater than or equal to 7 days, were given individual LCO 3.0.4 exceptions. During some conversions to the STS, individual plants provided acceptable justifications for other LCO 3.0.4 exceptions. All of these specific LCO 3.0.4 exceptions allow entry into a mode or other specified condition in the TS applicability

while relying on the TS required actions and associated CTs. The proposed change under evaluation would provide standardization and consistency to the use and application of LCO 3.0.4, both internal to and between each of the specifications and STS NUREGs. This proposed change will also ensure consistency by using appropriate levels of risk assessment of plant configurations for application of LCO 3.0.4. However, nothing in this SE should be interpreted as encouraging upward mode transition with inoperable equipment. Good practice should dictate that such transitions should normally be initiated only when all required equipment is operable and that mode transition with inoperable equipment should be the exception rather than the rule.

The current LCO 3.0.4.a allowances are retained in the proposal and do not represent a change in risk from the current situation. The LCO 3.0.4.b allowances apply to systems and components, and require a risk assessment prior to use to ensure an acceptable level of safety is maintained. The LCO 3.0.4.c allowances apply to parameters and values that have been previously approved by the NRC in a plants specific TS. NMC will put in its TS Bases a discussion and list of each NRC-approved, LCO 3.0.4.c-specific value and parameter allowance. The bases of LCO 3.0.4 will be revised to explain the new allowances and their use.

The NRC staff did a qualitative assessment of the risk impact of the proposed change in LCO 3.0.4.b allowances by evaluating how NMCs implementation of the proposed risk-informed approach is expected to meet the guidance of the applicable RGs. The NRC staff referred to the guidance provided in RG 1.174 and in RG 1.177. RG 1.177 provides the NRC staffs recommendations on using risk information to assess the impact of proposed changes to nuclear power plant TS on the risk associated with plant operation. Although RG 1.177 does not specifically address the type of generic change in this proposal, the NRC staff considered the approach documented in RG 1.177 in evaluating the risk information provided in support of the proposed changes in LCO 3.0.4.

The NRC staffs evaluation of how the implementation of the proposed risk-informed approach, used to justify LCO 3.0.4.b allowances, agrees with the objectives of the guidance outlined in RG 1.177 is discussed below in Section 3.1. Oversight of the risk-informed approach associated with the LCO 3.0.4.b allowances is discussed below in Section 3.2.

3.1 Evaluation of Risk Management Both the temporary and cumulative risks of the proposed change are adequately limited. The temporary risk is limited by the exclusion of higher-risk systems and components, and CT limits contained in Section 3.1.1. The cumulative risk is limited by the temporary risk limitations and by the expected low frequency of the proposed mode changes with inoperable equipment as discussed below in Section 3.1.4. Adequate NRC oversight of NMCs ability to use the LCO 3.0.4.b provisions under appropriate circumstances (i.e., to identify risk-significant configurations when entering a higher mode or condition in the applicability of an LCO as discussed below in Section 3.1.5) is provided by NRC inspection of NMCs implementation of 10 CFR 50.65(a)(4) as applied to the proposed change.

3.1.1 Temporary Risk Increases RG 1.177 proposes the incremental conditional core damage probability (ICCDP) and the incremental conditional large early release probability (ICLERP) as appropriate measures of the increase in probability of core damage and large early release, respectively, during the period of implementation of a proposed TS change. In addition, RG 1.177 stresses the need to preclude potentially high risk configurations introduced by the proposed change. The ICCDP associated with any specified plant condition, such as the condition introduced by entering a higher mode with plant equipment inoperable, is expressed by the following equation:

ICCDP = R d = (R1 - Ro) d where:

R = the conditional risk increase, in terms of core damage frequency (CDF),

caused by the specified condition d = the duration of the specified plant condition R1 = the plant CDF with the specified condition permanently present Ro = the plant CDF without the specified condition The same expression can be used for ICLERP by substituting the measure of risk (i.e., large early release frequency (LERF) for CDF). The magnitude of the ICCDP and ICLERP values associated with plant conditions applicable to LCO 3.0.4.b allowances can be managed by controlling the conditional risk increase, R (in terms of both CDF and LERF) and the duration, d, of such conditions. The following sections discuss how the key elements of the proposed risk-informed approach, used to justify LCO 3.0.4.b allowances, are expected to limit R and d and, thus, prevent any significant temporary risk increases.

3.1.2 Identification of Risk-Important TS Systems and Components A major element that limits the risk of the proposed mode change flexibility is the exclusion of certain systems and associated LCOs for the mode change allowance. TS allow operation in Mode 1 (power operation) with specified levels of inoperability for specified times. This provides a benchmark of currently acceptable risk against which to measure any incremental risk inherent in the proposed LCO 3.0.4.b. If a systems inoperability accrues risk at a higher rate in one or more of the transition modes than it would in Mode 1, then an upward transition into that mode should not be allowed without demonstration of a high degree of experience and sophistication in risk management. However, the risk management process evaluated in Section 3.1.5 is adequate if higher-risk systems/components are excluded from the scope of LCO 3.0.4.b.

The importance of most TS systems in mitigating accidents increases as power increases.

However, some TS systems are relatively more important during lower power and shutdown operations, because of the following:

  • Certain events are peculiar to modes of plant operation other than power operation.
  • Certain events are more probable at modes of plant operation other than power operation.
  • Some modes of plant operation have less mitigation system capability than power operation.

The risk information submitted in support of the proposed changes to LCO 3.0.4 and SR 3.0.4 includes qualitative risk assessments performed by each owners group to identify higher-risk systems and components at the various modes of operation, including transitions between modes, as the plant moves upward from the refueling mode of operation toward power operation. The owners groups' generic qualitative risk assessments are included as attachments to TSTF-359, Revision 9. Each of the owners groups' generic qualitative risk assessments discusses the technical approach used and the systems/components subsequently determined to be of higher risk significance; the systems/components not to be granted the LCO 3.0.4 allowances for the various modes are listed. The owners groups' generic qualitative risk assessments are:

  • BWR Owners Group Risk-Informed Technical Specification Committee, Technical Justification to Support Risk-Informed Improvements to Technical Specification Mode Restraints for BWR Plants, General Electric Company GE-NE A13-00464 (Rev. 2).
  • B&W Owners Group Qualitative Risk Assessment for Increased Flexibility in MODE Restraints, Framatome Technologies BAW-2383, October 2001.
  • Combustion Engineering Owners Group Task 1181, Qualitative Risk Assessment for Relaxation of Mode Entry Restraints, CE Nuclear Power LLC, CE NPSD-1207 (Rev. 0).
  • WOG Qualitative Risk Assessment Supporting Increased Flexibility in MODE Restraints, January 2002.

Following interactions with the NRC staff, all owners groups used the same systematic approach in their qualitative risk assessments to identify the higher-risk systems in the STS.

The approach consisted of steps to identify the following:

  • plant conditions (i.e., plant parameters and availability of key mitigation systems) associated with changes in plant operating modes while returning to power
  • key activities that have the potential to impact risk and which are in progress during transitions between modes while the plant is returning to power
  • applicable accident initiating events for each mode or other specified condition in the applicability
  • higher-risk systems and components by combining the information in the first three steps (qualitative risk assessment)

The risk assessments properly used the results and insights from previous deterministic and probabilistic studies to systematically search for plant conditions in which certain key plant components are more important in mitigating accidents than during operation at power (Mode 1). This search was systematic, taking the following factors into account for the various stages of returning the plant to power:

  • status of accident mitigation and normally operating systems
  • key activities that are in progress during transitions between modes which have the potential to impact risk (e.g., the transfer from auxiliary to main feedwater at some PWR plants when Mode 1 is entered)
  • design and operational differences among plants or groups of plants The CEOG identified the following systems and components as higher-risk systems and components, when the plant is entering a new mode.

WOG Plants System Entering Mode Emergency Diesel Generation 5, 4, 3, 2, 1 Auxiliary Feedwater (AFW) System (for plants depending on AFW for startup) 4, 3, 2 ,1 High-Head Safety Injection System 4 Cold Overpressure Protection System 5, 4 Residual Heat Removal System 5 If the licensee identifies a higher-risk system for only some of the modes of applicability, the TS for that system would be modified by a note that reads, for example, "LCO 3.0.4.b is not applicable when entering MODE 1 from MODE 2." Systems identified as higher risk for Modes 5 and 6 for PWRs, and Modes 4 and 5 for BWRs, are also excluded from transitioning up to the mode of higher risk and, as previously discussed, notes for those transitions are superfluous. In addition, mode transitions for Modes 5 and 6 for PWRs, and Modes 4 and 5 for BWRs, will be addressed by administrative controls.

In summary, the NRC staffs review of the owners groups' qualitative risk assessments finds that they are of adequate quality to support the application (i.e., they identify the higher-risk systems and components associated with entering higher modes of plant operation with equipment inoperable while returning to power).

NMC has adopted the TSTF-359 wording for LCO 3.0.4 and SR 3.0.4. Existing notes stating that LCO 3.0.4 is not applicable have been deleted from various TS LCOs as described in TSTF-359 and the supporting documentation. The format and numbering of the Point Beach TS vary from the STS, but the changes proposed are consistent with TSTF-359 and this SE.

LCO 3.0.4.c has been referenced appropriately for the TS defining limits on parameters and values to maintain the flexibility provided by the existing statement that LCO 3.0.4 is not applicable. NMC has, consistent with the above table, added notes to the appropriate TS to state that the revised LCO 3.0.4.b allowing mode changes with inoperable equipment is not applicable to the identified higher-risk systems.

3.1.3 Limited Time in TS Required Actions Any temporary risk increase will be limited by, among other factors, duration constraints imposed by the TS CTs of the inoperable systems. For the systems and components that are not higher risk, any temporary risk increase associated with the proposed allowance will be smaller than what is considered acceptable when the same systems and components are inoperable at power. This is due to the fact that CTs associated with the majority of TS systems and components were developed for power operation and pose a smaller plant risk for action statement entries initiated or occurring at lower modes of operation as compared to power operation.

The LCO 3.0.4.b allowance will be used only when the licensee determines that there is a high likelihood that the LCO will be satisfied following the mode change. This will minimize the likelihood of additional temporary risk increases associated with the need to exit a mode due to failure to restore the unavailable equipment within the CT. In most cases, the licensee will enter into a higher mode with the intent to move up to Mode 1 (power operation). As discussed below in Section 3.2, the revised ROP monitors unplanned power changes as a performance indicator. The ROP, thus, discourages licensees from entering a mode or other specified condition in the applicability of an LCO, and moving up in power, when there is a likelihood that the mode would have to be subsequently exited due to failure to restore the unavailable equipment within the CT. Another disincentive for the licensee to enter a higher mode when an LCO is not met is related to reporting requirements. It clearly states in 10 CFR 50.72, Immediate notification requirements for operating nuclear power reactors, that a report is required when the initiation of a nuclear plant shutdown is required by TS. The NRCs oversight program will provide the framework for inspectors and other staff to follow the history at a specific plant of entering higher modes while an LCO is not met, and use such information in assessing the licensees actions and performance.

3.1.4 Cumulative Risk Increases The cumulative risk impact of the change to allow the plant to enter a higher mode of operation with one or more safety-related components unavailable (as proposed here), is measured by the average yearly risk increase associated with the change. In general, this cumulative risk increase is assessed in terms of both CDF and LERF (i.e., CDF and LERF, respectively).

The increase in CDF due to the proposed change is expressed by the following equation, which integrates the risk impact from all expected specified conditions (i.e., all expected plant conditions caused by mode changes with various TS systems and components unavailable).

CDF = j(CDFi) = j ICCDPi fi where:

CDFi = the CDF increase due to specified condition i ICCDPi = the ICCDP associated with specified condition i fi = the average yearly frequency of occurrence of specified condition i A similar expression can be used for LERF by substituting the measure of risk (i.e., LERF for CDF). The magnitude of the CDF and LERF values associated with plant conditions applicable to LCO 3.0.4.b allowances can be managed by controlling the temporary risk

increases, in terms of both CDF and LERF (i.e., ICCDP and ICLERP), and the frequency (f), of each of such conditions. In addition to the points made in the previous section regarding temporary risk increases, the following points put into perspective how the key elements of the proposed risk-informed approach, used to justify an LCO 3.0.4.b allowance, are expected to prevent significant cumulative risk increases by limiting the frequency of its use:

  • The frequency of risk significant conditions will be limited by not providing the LCO 3.0.4.b allowances to the higher risk systems and components.
  • The frequency of risk significant conditions will be limited by the requirement to assess the likelihood that the LCO will be satisfied following the mode change.
  • The frequency of risk significant conditions is limited by the fact that such conditions can occur only when the plant is returning to power following shutdown (i.e., during a small fraction of time per year). Data over the past 5 years indicate that the plants are averaging 2.1 startups per year.
  • The addition of the proposed LCO 3.0.4.b allowances to the plant maintenance activities is not expected to change the plants average (cumulative) risk significantly.

3.1.5 Risk Assessment and Risk Management of Mode Changes With all safety systems and components operable, a plant can transition up in mode to power operation. With one or more system(s) or component(s) inoperable, this change permits a plant to transition up in mode to power operation if the following occur:

  • The inoperable system(s) or component(s) are not in the pre-analyzed higher risk category.
  • A 10 CFR 50.65(a)(4)-based risk assessment is performed prior to the mode transition.
  • The requisite risk management actions are taken.

NMCs proposed TS Bases for LCO 3.0.4 states that, LCO 3.0.4.b allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate. The risk assessment may use quantitative, qualitative, or blended approaches, and the risk assessment will be conducted using the plant program, procedures, and criteria in place to implement 10 CFR 50.65(a)(4), which requires that risk impacts of maintenance activities to be assessed and managed. It should be noted that the risk assessment, for the purposes of LCO 3.0.4.b, must take into account all inoperable TS equipment regardless of whether the equipment is included in NMCs normal 10 CFR 50.65(a)(4) risk assessment scope. The risk assessments will be conducted using the procedures and guidance endorsed by RG 1.182. The results of the risk assessment shall be considered in determining the acceptability of entering the MODE or other specified condition in the Applicability, and any corresponding risk management actions. A risk assessment and establishment of risk management actions, as appropriate, are required for determination of acceptable risk for entering MODES or other specified conditions in the Applicability when an LCO is not met. Elements of acceptable risk assessment and risk

management actions are included in Section 11 of NUMARC 93-01, Assessment of Risk Resulting from Performance of Maintenance Activities, as endorsed by RG 1.182, which addresses general guidance for conduct of the risk assessment, gives quantitative and qualitative guidelines for establishing risk management actions, and provides example risk management actions. These risk management actions include actions to plan and conduct other activities in a manner that controls overall risk, actions to increase risk awareness by shift and management personnel, actions to reduce the duration of the conditions, actions to minimize the magnitude of risk increases (establishment of backup success paths or compensatory measures), and determination that the proposed MODE change is acceptable.

The guidance references state that a licensees risk assessment process should be sufficiently robust and comprehensive to assess risk associated with maintenance activities during power operation, low power, and shutdown conditions (all modes of operation), including changes in plant conditions. NUMARC 93-01 states that the risk assessment should consider the following:

  • degree of redundancy available for performance of the safety function(s) served by the out-of-service equipment
  • duration of the out-of-service condition
  • component and system dependencies that are affected
  • risk impact of performing the maintenance during shutdown versus at power
  • impact of mode transition risk For power operation, key plant safety functions are those that ensure the integrity of the reactor coolant pressure boundary, ensure the capability to shut down and maintain the reactor in safe shutdown condition, and ensure the capability to prevent or mitigate the consequences of accidents that could result in potentially significant offsite exposures.

While the inoperabilities permitted by the CTs of TS required actions take into consideration the safety significance and redundancy of the system or components within the scope of an LCO, the CTs generally do not address or consider concurrent system or component inoperabilities in multiple LCOs. Therefore, performing the 10 CFR 50.65(a)(4) risk assessment, which looks at the entire plant configuration, is essential (and required) prior to changing operational mode.

The 10 CFR 50.65(a)(4)-based risk assessment will be used to confirm (or reject) the appropriateness of transitioning up in mode given the actual status of plant safety equipment.

The risk impact on the plant condition of invoking an LCO 3.0.4.b allowance will be assessed and managed through the program established to implement 10 CFR 50.65(a)(4). This program is consistent with RG 1.177 and RG 1.174 in its approach. The implementation guidance for paragraph (a)(4) of the Maintenance Rule addresses controlling temporary risk increases resulting from maintenance activities. This guidance, consistent with guidance in RG 1.177, establishes action thresholds based on qualitative and quantitative considerations and risk management actions. Significant temporary risk increases following an LCO 3.0.4.b allowance are unlikely to occur unless:

  • High-risk configurations are allowed (e.g., certain combinations of multiple component outages), or
  • Risk management of plant operation activities is inadequate.

The requirements associated with the proposed change are established to ensure that such conditions will not occur.

The thresholds of the cumulative (aggregate) risk impacts, assessed pursuant to 10 CFR 50.65(a)(4) and the associated implementation guidance, are based on the permanent change guidelines in RG 1.174. Therefore, the licensee will manage the risk by exercising LCO 3.0.4 in conjunction with the risk from other concurrent plant activities to ensure that any increase, in terms of CDF and LERF, will be small and consistent with the Commissions Safety Goal Policy Statement.

3.2 Oversight The ROP provides a means for assessing the licensees performance in the application of the proposed mode change flexibility. The adequacy of the licensees assessment and management of maintenance-related risk is addressed by existing inspection programs and guidance for 10 CFR 50.65(a)(4). Although the current versions of that guidance do not specifically address application of the licensees Section 50.65(a)(4) program to support risk-informed TS, it is expected that risk assessment and management associated with risk-informed TS would be required by Section 50.65(a)(4) because maintenance activities will be involved.

Adoption of the proposed change will make failure to assess and manage the risk of an upward mode change with inoperable equipment covered by TS, prior to commencing such a mode change, a violation of TS. Further, as explained above in general, under most foreseeable circumstances, such a change in configuration would also require a risk assessment under 10 CFR 50.65(a)(4). Inoperable systems or components will necessitate maintenance to restore them to operability, and, hence, a 10 CFR 50.65(a)(4) risk assessment would be performed prior to the performance of those maintenance actions (except for immediate plant stabilization and restoration actions if necessary). Further, before altering the plant configuration, including plant configuration changes associated with mode changes, the licensee must update the existing Section 50.65(a)(4) risk assessment to reflect those changes.

The July 19, 1999, Federal Register notice (64 FR 38551) issuing a revision to the maintenance rule along with NRC IP 71111.13 and Section 11 of NUMARC 93-01, indicate that to determine the safety impact of a change in plant conditions during maintenance, a risk assessment must be performed before changing plant conditions. The bases for the proposed TS change mandate that the risk assessment and management of upward mode changes will be conducted under the licensees program and process for meeting 10 CFR 50.65(a)(4).

Oversight of licensee performance in assessing and managing the risk of plant maintenance activities is conducted principally by inspection in accordance with ROP Baseline IP 71111.13.

Supplemental IP 62709 is used to evaluate the licensees process, when necessary.

The ROP is described in overview in NUREG-1649, Revision 3, Reactor Oversight Process, and in detail in the NRC Inspection Manual. IP 71111.13 provides for verification of adequacy

of risk assessments when they are required by 10 CFR 50.65(a)(4) and in accordance with licensee procedures. The procedure also provides for verification of the adequacy of those risk assessments and verification of effective implementation of licensee-prescribed risk management actions. The rule itself requires such assessment and management of risk prior to maintenance activities, including preventive maintenance, surveillance, and testing (and promptly for emergent work) during all modes of plant operation. The guidance documents for both industry implementation of Section 50.65(a)(4) and NRC oversight of that implementation indicate that changes in plant configuration (which would include mode changes) in support of maintenance activities must be taken into account in the risk assessment and management process. Revisions to NRC inspection guidance and licensee implementation procedures will be needed to address oversight of risk assessment and management required by TS in support of mode changes that are not already required under the circumstances by Section 50.65(a)(4).

This consideration provides performance-based regulatory oversight of the use of the proposed flexibility, and a disincentive to use the flexibility without the requisite care in planning.

In addition, the NRC staff is in the process of developing detailed SDP guidance for use in assessing inspection findings related to 10 CFR 50.65(a)(4). This guidance was issued in draft for comment and is anticipated to become final during 2004. The ROP considers inspection findings and performance indicators in evaluating licensee ability to operate safely. The SDP is used to determine the significance of inspection findings related to licensee assessment and management of the risk associated with performing maintenance activities under all plant operating or shutdown conditions. Unplanned reactor scrams and unplanned power changes are two of the Reactor Safety Performance Indicators that the ROP utilizes to assess licensee performance and inform the public. The ROP will provide a disincentive to entering into power operation (Mode 1) when there is a significant likelihood that the mode would have to be subsequently exited due to failure to restore the unavailable equipment within the CT.

NMC included in its application the revised TS Bases to be implemented with the TS change.

The NRC staff finds that the TS Bases Control Program is the appropriate process for updating the affected TS Bases pages and has, therefore, not included the affected Bases pages with these amendments.

3.3 Summary The industry, through the NEI RITSTF, has submitted a proposed TS change to allow entry into a higher mode of operation, or other specified condition in the TS applicability, while relying on the TS conditions, and associated required actions and CTs, provided a risk assessment is performed to confirm the acceptability of that action. The proposal revises STS LCO 3.0.4 and SR 3.0.4, and their application to the TS. New paragraphs a, b, and c are proposed for LCO 3.0.4.

The proposed LCO 3.0.4.a retains the current allowance, permitting the mode change when the TS required actions allow indefinite operation. Proposed LCO 3.0.4.b is the change to allow entry into a higher mode of operation, or other specified condition in the TS applicability, while relying on the TS conditions and associated required actions and CTs, provided a risk assessment is performed to confirm the acceptability of that action for the existing plant configuration. The NRC staff review finds that the process proposed by industry for assessing and managing risk during the implementation of the proposed LCO 3.0.4.b allowances meets Commission guidance for TS changes. Key elements of this process are listed below.

C A risk assessment shall be performed before any LCO 3.0.4.b allowance is invoked.

C The risk impact on the plant condition of invoking an LCO 3.0.4.b allowance will be assessed and managed through the program established to implement 10 CFR 50.65(a)(4) and the associated guidance in RG 1.182. Allowing entry into a higher mode or condition in the applicability of an LCO after a 10 CFR 50.65(a)(4)-based risk assessment and appropriate risk management actions are taken for the existing plant configuration will ensure that plant safety is maintained.

C The LCO 3.0.4.b allowance will be used only when NMC determines that there is a high likelihood that the LCO will be satisfied within the required actions CT.

C TS systems and components that may be of higher risk during mode changes have been identified generically by each owners group for each plant operational mode or condition.

The licensee will identify such plant-specific systems and components in the individual plant TS. The proposed LCO 3.0.4.b allowance does not apply to these systems and components for the mode or condition in the applicability of an LCO at which they are of higher risk.

C Plants adopting LCO 3.0.4.b will ensure that plant procedures in place to implement 10 CFR 50.65(a)(4) address the situation where entering a mode or other specified condition in the applicability is contemplated with plant equipment inoperable. Such plant procedures typically follow the guidance in NUMARC 93-01, Section 11, as revised in February 2000, and endorsed by NRC RG 1.182.

The NRCs ROP provides the framework for inspectors and other staff to oversee the implementation of 10 CFR 50.65(a)(4) requirements at a specific plant and assess NMCs actions and performance.

The LCO 3.0.4.b allowance does not apply to values and parameters of the TS that have their own respective LCOs (e.g., Reactor Coolant System Specific Activity), but instead those values and parameters are addressed by LCO 3.0.4.c. The TS values and parameters for which mode transition allowances apply will have a note that states 3.0.4.c is applicable. The objective of the proposed change is to provide additional operational flexibility without compromising plant safety.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Wisconsin State official was notified of the proposed issuance of the amendment. The Wisconsin State official had no comments.

5.0 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 (69 FR 55844). 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.

6.0 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 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.

Principal Contributor: T. Tjader W. Reckley Date: December 22, 2004

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