ML020310114

Issuance of License Amendment - Revises the Allowed Outage Time from 72 Hours to 7 Days for One Low Pressure Injection Train, and One Containment Spray System Train

ML020310114
Person / Time
Site:	Davis Besse
Issue date:	09/17/2002
From:	Hopkins J NRC/NRR/DLPM/LPD3
To:	Myers L FirstEnergy Nuclear Operating Co
Hopkins J , NRR/DLPM, 301-415-3027
Shared Package
ML022610687	List: ML020310114 ML022610102
References
TAC MA9694
Download: ML020310114 (15)

Text

September 17, 2002 Mr. Lew W. Myers Vice President-Nuclear, Davis-Besse FirstEnergy Nuclear Operating Company Davis-Besse Nuclear Power Station 5501 North State Route 2 Oak Harbor, OH 43449-9760

SUBJECT:

DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - ISSUANCE OF AMENDMENT (TAC NO. MA9694 )

Dear Mr. Myers:

The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment No. 253 to Facility Operating License No. NPF-3 for the Davis-Besse Nuclear Power Station (DBNPS),

Unit 1. The amendment revises the Technical Specifications (TSs) in response to your application dated November 9, 2000, as supplemented by letter dated November 3, 2001.

This amendment revises the allowed outage time from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days for one low pressure injection train, and one containment spray system train. The supporting analysis for the request is based on the Babcock & Wilcox Owners Group (B&WOG) Topical Report BAW-2295A, Revision 1 & 2, Justification for the Extension of Allowed Outage Time for Low pressure Injection and Reactor Building Spray Systems, and its review by the staff documented in a safety evaluation report. The DBNPS is the lead B&WOG plant requesting these changes to be made to the TSs.

A copy of the Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's next biweekly Federal Register notice.

Sincerely,

/RA/

Jon B. Hopkins, Senior Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-346

Enclosures:

1. Amendment No. 253 to License No. NPF-3

2. Safety Evaluation cc w/encls: See next page

ML020310114

• See Previous Concurrence OFFICE PM:LPD3-2 LA:LPD3-2*

SPSB*

OGC*

SC:LPD3-2 NAME JHopkins CRosenberg MCaruso AFernandez AMendiola DATE 9/11/02 8/26/02 1/28/02 9/10/02 9/16/02

Mr. Lew W. Myers Davis-Besse Nuclear Power Station, Unit 1 FirstEnergy Nuclear Operating Company cc:

Mary E. OReilly Dennis Clum FirstEnergy Radiological Assistance Section Supervisor 76 South Main Street Bureau of Radiation Protection Akron, OH 44308 Ohio Department of Health P.O. Box 118 Manager - Regulatory Affairs Columbus, OH 43266-0118 FirstEnergy Nuclear Operating Company Davis-Besse Nuclear Power Station Carol OClaire, Chief, Radiological Branch 5501 North State - Route 2 Ohio Emergency Management Agency Oak Harbor, OH 43449-9760 2855 West Dublin Granville Road Columbus, OH 43235-2206 Director Ohio Environmental Protection Agency Ohio Department of Commerce DERR--Compliance Unit Division of Industrial Compliance ATTN: Zack A. Clayton Bureau of Operations & Maintenance P.O. Box 1049 6606 Tussing Road Columbus, OH 43266-0149 P.O. Box 4009 Reynoldsburg, OH 43068-9009 Public Utilities Commission of Ohio Transportation Department Regional Administrator 180 East Broad Street U.S. Nuclear Regulatory Commission Columbus, OH 43215-3793 801 Warrenville Road Lisle, IL 60523-4351 Attorney General Department of Attorney Michael A. Schoppman 30 East Broad Street Framatome ANP Columbus, OH 43216 1911 N. Ft. Myer Drive Rosslyn, VA 22209 President, Board of County Resident Inspector Commissioners of Ottawa County U.S. Nuclear Regulatory Commission Port Clinton, OH 43252 5503 North State Route 2 Oak Harbor, OH 43449-9760 Plant Manager, Randel J. Fast FirstEnergy Nuclear Operating Company Davis-Besse Nuclear Power Station 5501 North State - Route 2 Oak Harbor, OH 43449-9760

FIRSTENERGY NUCLEAR OPERATING COMPANY DOCKET NO. 50-346 DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 253 License No. NPF-3 1.

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

A.

The application for amendment by the FirstEnergy Nuclear Operating Company (the licensee) dated November 9, 2000, as supplemented by letter dated November 3, 2001, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions 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 Commissions 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 Commissions 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 2.C.(2) of Facility Operating License No. NPF-3 is hereby amended to read as follows:

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 253, are hereby incorporated in the license. FirstEnergy Nuclear Operating Company shall operate the facility in accordance with the 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/

Anthony J. Mendiola, Chief, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance: September 17, 2002

ATTACHMENT TO LICENSE AMENDMENT NO. 253 FACILITY OPERATING LICENSE NO. NPF-3 DOCKET NO. 50-346 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 3/4 5-3 3/4 5-3 3/4 6-11 3/4 6-11 B 3/4 5-1 B 3/4 5-1 B 3/4 5-1a

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 253 TO FACILITY OPERATING LICENSE NO. NPF-3 FIRSTENERGY NUCLEAR OPERATING COMPANY DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 DOCKET NO. 50-346

1.0 INTRODUCTION

By letter dated November 9, 2000, as supplemented by letter dated November 3, 2001, FirstEnergy Operating Company, the licensee for the Davis-Besse Nuclear Power Station (DBNPS), submitted a license amendment application to revise the DBNPS Technical Specifications (TS). The requested changes extend the allowed outage time (AOT) for one low pressure injection (LPI) train (including the associated decay heat cooler) and one containment spray system (CSS) train. The decay heat cooler is included with its associated LPI train because the LPI system in Babcock & Wilcox (B&W) plant designs, such as the DBNPS, is combined with the decay heat removal (DHR) system. The AOT extension for one CSS train is requested because each CSS train shares some common suction piping with its corresponding LPI system train and may be impacted by the inoperability of the associated LPI train.

The proposed AOT extension will allow additional pump and valve maintenance and testing to be performed at power (on-line), including both corrective maintenance and voluntary entry into the limiting condition of operation (LCO) for preventative maintenance and testing. Thus, the licensee will be able to perform at power preventative maintenance that is now being performed during a plant refueling outage when the DHR system, which is combined with the LPI system, is in service.

The supporting analysis for the licensees request is based on the Babcock & Wilcox Owners Group (B&WOG) Topical Report BAW-2295A, Revision 1 & 2, Justification for the Extension of Allowed Outage Time for Low pressure Injection and Reactor Building Spray Systems, which was submitted to the Nuclear Regulatory Commission (NRC) by letter dated October 9, 1998.

This topical report, which addressed seven B&W plant units (including DBNPS), was reviewed by the staff and its findings were documented in a safety evaluation report (SER). The DBNPS is the lead B&W plant requesting these changes to be made to the TSs.

2.0 PROPOSED TS CHANGES Current DBNPS TS Action statements require a 72-hour AOT for one LPI/decay heat cooler train (LCO 3.5.2). The licensee proposes the extension of this AOT from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 7 days (168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />). In addition, because one CSS train may be impacted by the inoperability of the associated LPI train, the licensee also proposes to extend the current 72-hour AOT for one CSS train (LCO 3.6.2.1) to 7 days (168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />).

3.0 EVALUATION 3.1 Deterministic Evaluation The CSS is designed to remove heat and fission product iodine from the post-accident containment atmosphere. The system consists of two independent trains. Each train consists of a pump, a spray header, valves, and associated piping, instrumentation, and controls. Each train is capable of performing the required safety functions by taking suction from the borated water storage tank on a containment spray actuation signal or transferring suction to the containment emergency pump during the recirculation phase of operation.

The DBNPS stated that the proposed changes are based on the B&WOG topical report, BAW-2295A, Revision 1 and 2, Justification for the Extension of Allowed Outage Time for Low Pressure Injection and Reactor Building Spray Systems. This topical report addressed seven B&W plants, including the DBNPS. The topical report included both deterministic evaluation and probabilistic evaluation. In the deterministic evaluation, the NRC staff evaluated and concluded in the SE dated June 30, 1999, that the proposed allowable outage time of 7 days was acceptable.

In 10 CFR 50.36 it states that LCO in TS are the lowest functional capability or performance levels of equipment required for safe operation of the facility. In the deterministic evaluation, based on the conclusion of the SER for the topical report and the adequacy of one train of the spray system satisfying the minimum capability requirement for the safety function of the containment spray system, the staff finds the proposed allowable outage time of 7 days acceptable.

The DBNPS deterministic evaluation was submitted as part of topical report BAW-2295A and has been previously approved in the staff SER dated June 30, 1999. The plant-specific information submitted in support of this license amendment request was reviewed to ensure conformance to the referenced topical report and the associated staff SER, and found to be acceptable.

3.2 Probabilistic Safety Assessment Evaluation 3.2.1 Evaluation Criteria In evaluating the risk assessment information provided in topical report BAW-2295A, the staff followed the three-tiered approach documented in regulatory guide (RG), RG 1.177, An approach for Plant-Specific, Risk-Informed Decision Making: Technical Specifications. The first tier of the three-tiered approach includes the assessment of the risk impact of the proposed change for comparison to acceptance guidelines consistent with the Commissions Safety Goal Policy Statement, as documented in RG 1.174 entitled, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis. In addition, the first tier aims at ensuring that the plant risk does not increase unacceptably during the period the equipment is taken out of service. The second tier addresses the need to preclude potentially high risk configurations which could result if equipment in addition to that associated with the change are taken out of service simultaneously. The third tier addresses the establishment of an overall configuration risk management program (CRMP) for identifying risk significant configurations resulting from maintenance or other operational activities and taking appropriate compensatory measures to avoid such configurations. In addition, the staffs evaluation of the topical report, BAW-2295A, discusses what additional plant-specific information each licensee is expected to furnish with its application to ensure adequate probabilistic risk assessment (PRA) quality.

The plant-specific information, submitted by DBNPS in support of its license amendment application, was evaluated to ensure conformance with requirements listed in the staffs SER of the referenced topical report. These requirements include the need on the part of the licensee to:

• implement four compensatory measures,

• provide plant-specific information about any changes in the PRA model or the plant which could affect the conclusions of the risk assessment documented in the referenced topical report, and

• discuss whether a CRMP or other administratively controlled document is in place which contains the key elements stated in the staffs SER of the topical report.

The staff has determined, as stated in the referenced topical report SER, that the satisfaction of these requirements satisfies the criteria of the three-tiered approach and ensures the quality of the PRA model used to assess the risk impact of the proposed change.

3.2.2 Risk Impact of the Proposed Change (Tier 1)

An acceptable approach to risk-informed decision making is to show that the proposed change to the licensing basis meets several key principles outlined in RG 1.174. One of these principles is to show that the proposed change results in an increase in risk, in terms of core damage frequency (CDF) and large early release frequency (LERF), which is small and consistent with the Commissions Safety Goal Policy Statement. Acceptance guidelines for meeting this principle are presented in RG 1.174.

In the topical report BAW-2295A, and its associated staff SER, the mean yearly increases in CDF and LERF due to the proposed change were assessed to be less than 1E-6/yr and less than 1E-7/yr, respectively. These increases meet the acceptance guidelines of RG 1.174. The licensee did not quantify the potential reduction in the shutdown risk of the plant due to the fact that a significant portion of the preventive and corrective maintenance, currently performed during shutdown, would be performed during operation at power. Another potential benefit, which was also not quantified, is the avoidance of multiple entries into a LCO to complete LPI and CSS maintenance.

In addition to changes in the mean values of CDF and LERF, the licensee assessed the incremental conditional core damage probability (ICCDP) and the incremental conditional large early release probability (ICLERP). These quantities are a measure of the increase in probability of core damage and large early release, respectively, during a single outage assumed to last for the entire duration allowed by the proposed change. In the topical report BAW-2295A, and the associated staff SER, the following values of ICCDP and ICLERP, associated with internal events and power operation only, are reported:

• ICCDP: 1.5E-6

• ICLERP: 7.3E-8 These ICCDP and ICLERP estimates do not include the reduction in the shutdown risk of the plant due to the fact that a significant portion of maintenance, currently performed during shutdown, would be performed during operation at power. Another potential benefit, which was also not quantified, is the avoidance of multiple entries into a LCO to complete LPI and CSS maintenance. The estimated ICCDP and ICLERP values indicate that the proposed AOT increases are slightly above the acceptance guidance criteria of 5E-7 for ICCDP and 5E-8 for ICLERP, respectively, outlined in RG 1.177. For this reason, specific compensatory measures are discussed in the staffs SER of topical report BAW-2295A. These compensatory measures that would lower the risk impacts are the following:

• Avoiding simultaneous outages of additional risk-significant components during the AOT of the LPI and CSS trains. These components include both auxiliary feedwater (AFW) system trains, both high pressure injection (HPI) system trains (for reasons other than inoperable for high pressure recirculation due to the unavailability of the associated LPI train), both containment air cooler trains, and their power supplies.

• Defining specific criteria for scheduling only preventive maintenance which can be completed within the 7-day AOT, such that the chance for needing a forced outage for failing to complete the maintenance is negligible.

• Assuring that the frequency of entry into the allowable outage time and consequently, the average maintenance duration per year remains within that assumed in the topical report.

• Taking measures to assure that when maintaining the LPI and CSS trains, both are not made unavailable unless it is necessary.

• The licensee has committed in this license amendment request that the above listed compensatory measures will be implemented for outages involving LPI and/or CSS trains. As part of its implementation plan for these AOT changes, the licensee has identified controlling documents (under its License Amendment implementation plan) to assure that the above listed four compensatory measures will be properly implemented.

The staff finds that the implementation of the above listed compensatory measures ensures that the plant risk will not increase unacceptably when a LPI and/or CSS train are taken out of service for the entire proposed new AOT.

3.2.3 Avoidance of High Risk Plant Configurations (Tier 2)

An underlying assumption of the risk assessment, performed by the licensee in support of its AOT extension request, is that the entry into an extended LPI and CSS train AOT (7 days) will not be permitted if severe whether conditions are expected. In addition, it was assumed that when a LPI and/or CSS train is planned to be taken out of service, the availability of other risk important components will be verified. Analyses of the PRA results (cut sets and risk importance rankings), performed by the licensee, identified risk-significant components whose unavailability should be avoided during the AOT of one LPI and/or one CSS trains. These components include:

• both AFW system trains,

• both HPI system trains (for reasons other than inoperable for high pressure recirculation due to the unavailability of the associated LPI train),

• both containment air cooler trains, and

• all power supplies for the above listed systems.

The licensee committed to include precautions in the appropriate plant procedures for the above listed components to preclude high risk plant configurations during a planned outage of one LPI and/or one CSS train. The licensees documents used to implement the above compensatory measures are manual WPG-1, Administrative Work Process Guidelines Manual, procedure NG-DB-00001, On-Line Risk Management, and procedure DB-PF-00003, Maintenance Rule. Procedure NG-DB-00001 requires that risk-related maintenance activities be evaluated for risk and that appropriate levels of controls, approvals, and contingencies be applied. In addition, manual WPG-1 implements the protected train concept which allows only one risk-significant system, structure, or component to be taken out-of-service at any one time.

The staff finds that the proposed precautions, as well as their proposed implementation, are adequate for preventing the identified high risk plant configurations.

3.2.4 Configuration Risk Management Program (Tier 3)

The intent of a CRMP is to ensure that plant safety is maintained and monitored during an extended outage. The implementation of this program allows the licensee to make decisions and take appropriate actions to control risk when performing on-line maintenance. The DBNPS has been using PRA to assess the impact of daily planned activities on plant risk and has in place a CRMP that determines the risk associated with the removal of equipment from service and establishes minimum compensatory actions based on the risk level. The CRMP also prohibits entry into extended LPI system and/or CSS allowable outage times for scheduled maintenance purposes if external events conditions or warnings are in effect. The DBNPS guidance for its CRMP is contained in the administratively controlled Administrative Work Process Guidelines Manual, Work Scheduling Guideline, WPG-1. The CRMP that has been implemented per WPG-1 contains the four key elements described in the staffs safety evaluation of the referenced topical report BAW-2295A. The staff believes that the DBNPS CRMP provides adequate assurance that risk-significant configurations resulting from maintenance or other operational activities will be avoided during extended LPI system and/or CSS outages at the DBNPS.

3.2.5 PRA Quality The staffs safety evaluation of the referenced topical report BAW-2295A provides guidance regarding additional plant-specific information each licensee is expected to furnish with its application to ensure that the PRA model is of adequate quality to support the requested TS changes. In conformance with such guidance, the DBNPS included with its application the following information:

• Updates of the PRA model since the last review cycle, including corrections of weaknesses identified by past reviews and verification that the PRA reflects the as-built, as-operated plant,

• A description of the PRA peer review process, a summary of the peer review findings, and a discussion of the independence of internal reviews/reviewers, and

• A description of the DBNPS PRA quality assurance methods.

The licensee indicates that the PRA model was updated since the referenced topical report was submitted to include various design and procedural changes as well to address technical comments provided by the peer review process. This information indicates the living nature of the DBNPS PRA model which reflect the as-built, as-operated plant. Although several PRA updates (improvements) were made, since the original calculations for the topical report were performed, such calculations were repeated with the updated PRA model and the information provided in the Topical Report remained bounding.

Based on the above considerations and the applicable findings from the staffs review of the topical report BAW-2295A, the staff finds that the DBNPS PRA models of the plant are of adequate quality for assessing the impact of the proposed change on plant risk.

4.0

SUMMARY

AND CONCLUSION The staff reviewed the risk assessment information submitted by DBNPS to support its AOT extension request for one LPI train and one CSS train. This assessment is based on the three-tiered approach documented in RG 1.177. The plant-specific information, submitted by DBNPS in support of its license amendment application, was reviewed to ensure conformance with requirements listed in the staffs SER of the referenced topical report. These requirements include the need on the part of the licensee (1) to implement four compensatory measures, (2) to provide plant-specific information about any changes in the PRA model or the plant which could affect the conclusions of the risk assessment documented in the referenced topical report, and (3) to discuss whether a CRMP, or other administratively controlled document, is in place which contains the key elements stated in the staffs SER of the topical report. The major findings of the staffs review are summarized below:

• The staff finds that the DBNPS PRA model is of adequate quality to be used to assess the risk impact of the proposed change in the current allowed LPI/CSS AOT.

• The risk assessment indicates that the proposed change results in an increase in risk, in terms of CDF and LERF, which is small and consistent with the Commissions Safety Goal Policy Statement. The CDF would increase by less than 1E-6/yr and the LERF would increase by less than 1E-7/yr.

• The risk assessment indicates that the proposed change would not unacceptably increase the plant risk during the outage of one LPI/CSS train when the following compensatory measures are implemented as committed by the licensee:

• Avoiding simultaneous outages of additional risk-significant components during the AOT of the LPI and CSS trains. These components include both AFW system trains, both HPI system trains (for reasons other than inoperable for high pressure recirculation due to the unavailability of the associated LPI train), both containment air cooler trains, and their power supplies.

• Defining specific criteria for scheduling only preventive maintenance which can be completed within the 7-day AOT, such that the chance for needing a forced outage for failing to complete the maintenance is negligible.

• Assuring that the frequency of entry into the allowable outage time, and consequently the average maintenance duration per year, remains within that assumed in the topical report, BAW-2295A.

• Taking measures to assure that when maintaining the LPI and CSS trains, both are not made unavailable unless it is necessary.

• The licensee has identified controlling documents (under its license amendment implementation plan) to assure that the four compensatory measures will be properly implemented.

• The licensee used PRA to identify components whose unavailability should be avoided during the extended AOT and committed to include precautions in the appropriate plant procedures for the above listed components to preclude high risk plant configurations. These components include:

• both AFW system trains,

• both HPI system trains,

• both containment air cooler trains, and

• all power supplies for the above listed systems.

• The licensee has been using a risk-based CRMP which provides adequate assurance that risk-significant configurations resulting from maintenance or other operational activities will be avoided during the extended LPI/CSS outage.

The staff expects the licensee to implement the proposed TS change in accordance with the three-tiered approach described above. Also, the licensee will monitor LPI/CSS performance in relation to the Maintenance Rule performance criteria. Application of these implementation and monitoring strategies will help to ensure that the proposed AOT extension does not degrade operational safety over time and that the risk expected when one LPI and/or CSS train is taken out of service is minimized. The staff concludes that the risk information included in the DBNPS application supports the proposed AOT extension from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to seven days.

5.0 STATE CONSULTATION

In accordance with the Commissions regulations, the Ohio State official was notified of the proposed issuance of the amendment. The State official had no comments.

6.0 ENVIRONMENTAL CONSIDERATION

This amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluent 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 (65 FR 81919). 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 staff 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 Commissions regulations, and (3) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributors: N.Saltos C.Y.Li Date:

September 17, 2002