ML15261A245

Summary of 990311 Meeting with Duke in Rockville,Md Re Oconee License Renewal Application & Scoping Process Used by Duke to Comply with 10CFR54.4.List of Meeting Attendees & Util Presentation Matls Discussed at Meeting Encl

ML15261A245
Person / Time
Site:	Oconee
Issue date:	04/02/1999
From:	Joseph Sebrosky NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9904070403
Download: ML15261A245 (16)

Text

GV pRPREG, UNITED STATES 0

NUCLEAR REGULATORY COMMISSION t

WASHINGTON, D.C. 20555-0001 April 2-1999 LICENSEE:

Duke Energy Corporation (Duke)

FACILITY:

Oconee Nuclear Station, Units 1, 2, and 3

SUMMARY

OF MEETING BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION (NRC) STAFF AND DUKE REPRESENTATIVES REGARDING SCOPING FOR THE OCONEE LICENSE RENEWAL APPLICATION On March 11, 1999, representatives of Duke met with the NRC staff in Rockville, Maryland, to discuss the Oconee license renewal application. A list of meeting attendees is provided as. A copy of the staff's and Duke's presentation materials discussed at the meeting are provided as Enclosures 2 and 3, respectively.

The purpose of the meeting was to discuss the scoping process that was used by Duke to comply with 10 CFR 54.4. Duke had provided responses to the staff's requests for additional information (RAI) in this area in a February 17, 1999, letter. Based on an initial review of these responses the staff determined that it had-several questions still remaining regarding scoping. It was determined that a meeting would be the best avenue for attempting to answer the staff's questions. The staff developed the agenda in Enclosure 2 as an aid for the meeting. Duke slightly revised the agenda, which can be seen on the first page of Enclosure 3.

Duke began the meeting with an overview of the Oconee Safety Related Designation Clarification (OSRDC) project. A portion of the OSRDC program was used by Duke in the license renewal application. Duke explained that the OSRDC process involved 4 initiatives and that only the second initiative, although initiated for other purposes, was used for the license renewal application. Enclosure 2, agenda item 2, provides an overview of the initiatives for this process. Duke stated that the purpose of the first initiative was to verify Oconee's QA-1 licensing basis by developing a list of all QA-1 systems, structures, and components (SSCs) at Oconee in response to commitments made to the NRC as a result of Generic Letter (GL) 83-28, "Required Action Based on Generic Implications of Salem ATWS Event, dated July 8, 1983."

The QA-1 designation originally applied to Oconee SSCs which were relied upon to mitigate a large break loss-of-coolant accident (LBLOCA) coincident with a loss of offsite power (LOOP) event while not encompassing all SSCs requiring seismic design or single failure design criteria.

According to Duke, the purpose of the second initiative of the OSRDC project was to clarify Oconee's licensing basis with respect to design basis event mitigation requirements, i.e., to identify non QA-1 SSCs credited with accident mitigation functions.

The staff and Duke then discussed agenda item 9 of enclosure 2 regarding which design basis events (DBEs) were considered in-the Oconee license renewal scoping process. Specifically, the staff was interested in how Duke complied with the requirements of 10 CFR 54.4(a)(1) and with the definition of DBE in 10 CFR 50.49(b)(1). Duke reiterated its belief that the set of DBEs contained in Chapter 15 of the Oconee updated final safety analysis report (UFSAR) complies with the requirements of 10 CFR 54.4(a)(1) and meets the definition of 10 CFR 50.49(b)(1).

However, Duke stated that in order to be conservative it considered additional events based on plant-specific risk insights. As a result, Duke also considered: loss of main feedwater, turbine building flooding, tornado, seismic, external floods and groundwater, and snow and ice. Duke believes that its approach is consistent with the draft "Standard Review Plan (SRP) for the Review of License Renewal Applications for Nuclear Power Plants," and NEI 95-10 "Industry Guideline for Implementing the Requirements of 10 CFR Part 54-The License Renewal Rule."

Specifically, Duke noted that the draft SRP section Ill.A and NEI 95-10 Table 3.1-1 provided guidance on what documents should be reviewed in order to determine design basis events.

9904070403 990402 PDR ADOCK 05000269 P

PDR April 2, 1999 The staff's feedback was that the set of DBEs identified in Chapter 15 of the Oconee UFSAR do not satisfy the criteria in 10 CFR 54.4(a)(1) and that Duke's consideration of these additional DBEs is a requirement of the rule rather than an option. Accordingly, the staff and Duke agreed that resolution of this issue would require further senior management attention.

Duke provided a process overview for how the mechanical scoping was performed to satisfy 10 CFR 54.4(a)(1) and (a)(2) criteria. Agenda Item 3 of Enclosure 3 provides a high level description of this process. The process involves 4 steps. Step 1 identifies all mechanical flowpaths required to remain functional for successful design basis event mitigation. Step 2 identifies all physical pressure boundaries whose loss of fluid pressure integrity could impact the mechanical functions identified in Step 1. Step 3 identifies all portions of mechanical systems whose loss of pressure boundary or structural integrity would physically interfere with the function of any essential system and component. Step 4 of the process identifies all portions of mechanical systems designated as safety-related (QA-1), or seismic-related piping or as components that do not meet the criteria of 10 CFR 54.4(a)(1) or (a)(2). Duke then provided examples of drawings that reflected the results of the mechanical scoping process. Specifically, Duke showed the staff marked-up drawings at the 4 different steps in the process for 5 Oconee systems. The 5 systems presented were: (1) the standby shutdown facility reactor coolant makeup system, (2) the caustic addition portion of the chemical addition system, (3) the keowee turbine generator cooling water system, (4) the emergency feedwater system, and (5) the low pressure service water system.

Duke also explained its electrical scoping process. Duke discussed with the staff its RAI responses in this area to aid in the discussion. The main RAI in this area was RAI 2.6-1, however, the staff also discussed RAls 2.6-9, 2.6.1-1, 2.6.1-2, 2.6.1-3, 2.6.1-4, 2.6.7-1, and 2.6.7-2. Additionally, Duke provided the answers to the staff's agenda items 5, 6, 7, and 8, of enclosure 2 during this discussion.

As a result of the meeting Duke agreed to revise the responses to RAls 2.2-6, 2.6-1, 2.6.1-3, and 2.6.7-1 in order to address some of the staff's concerns. (Duke subsequently provided revised responses to these RAls in a March 18, 1999, letter). Specifically, Duke agreed to revise the response to RAI 2.2-6 to provide additional clarification that the staff requested. Duke also agreed to revise the response to RAI 2.6-1 to clarify the electrical scoping description and to indicate how the validation of the electrical results was performed. Duke also agreed to make conforming changes to RAI 2.6.1-3 and to provide a revised response to RAI 2.6.7-1 to indicate how the validation of structural results was performed. Finally, Duke agreed to consider making changes to RAI G-1 to address what type of quality assurance program would apply to corrective actions, confirmation process, and administrative controls to cover non-safety-related structures and components subject to aging management review.

Joseph M. Sebrosky, Project Manager License Renewal and Standardization Branch Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270, and 50-287

Enclosures:

As stated (3) cc w/encls: See next page DISTRIBUTION:

See next page

• See previous concurrence DOCUMENT NAME:G:\\SEBROSKY\\3-11 SUM.WPD OFFICE LA IQMB/DIPM RLSB/DRIP:PM RLSB:D NAME EHylton RLatta JSebrosky ClGrime DATE 4/01/99*

4/01 /99*

J / \\ 1i9 4 / /99 OFFICIAL RECORD COPY

-2 The staff's feedback was thatt of DBEs identified in Chapter 15 of the Oconee UFSAR do not satisfy the criteria in 10 CFR 54.4(a)(1) and that Duke's consideration of these additional DBEs is a requirement of the rule rather than an option. Accordingly, the staff and Duke agreed that resolution of this issue would require further senior management attention.

Duke provided a process overview for how the mechanical scoping was performed to satisfy 10 CFR 54.4(a)(1) and (a)(2) criteria. Agenda Item 3 of Enclosure 3 provides a high level description of this process. The process involves 4 steps. Step 1 identifies all mechanical flowpaths required to remain functional for successful design basis event mitigation. Step 2 identifies all physical pressure boundaries whose loss of fluid pressure integrity could impact the mechanical functions identified in Step 1. Step 3 identifies all portions of mechanical systems whose loss of pressure boundary or structural integrity would physically interfere with the function of any essential system and component. Step 4 of the process identifies all portions of mechanical systems designated as safety-related (QA-1), or seismic-related piping or as components that do not meet the criteria of 10 CFR 54.4(a)(1) or (a)(2). Duke then provided examples of drawings that reflected the results of the mechanical scoping process. Specifically, Duke showed the staff marked-up drawings at the 4 different steps in the process for 5 Oconee systems. The 5 systems presented were:*(1) the standby shutdown facility reactor coolant makeup system, (2) the caustic addition portion of the chemical addition system, (3) the keowee turbine generator cooling water system, (4) the emergency feedwater system, and (5) the low pressure service water system.

Duke also explained its electrical scoping process. Duke discussed with the staff its RAI responses in this area to aid in the discussion. The main RAI in this area was RAI 2.6-1, however, the staff also discussed RAls 2.6-9, 2.6.1-1, 2.6.1-2, 2.6.1-3, 2.6.1-4, 2.6.7-1, and 2.6.7-2. Additionally, Duke provided the answers to the staff's agenda items 5, 6, 7, and 8, of enclosure 2 during this discussion.

As a result of the meeting Duke agreed to revise the responses to RAls 2.2-6, 2.6-1, 2.6.1-3, and 2.6.7-1 in order to address some of the staff's concerns. (Duke subsequently provided revised responses to these RAls in a March 18, 1999, letter). Specifically, Duke agreed to revise the response to RAI 2.2-6 to provide additional clarification that the staff requested. Duke also agreed to revise the response to RAI 2.6-1 to clarify the electrical scoping description and to indicate how the validation of the electrical results was performed. Duke also agreed to make conforming changes to RAI 2.6.1-3 and to provide a revised response to RAI 2.6.7-1 to indicate how the validation of structural results was performed. Finally, Duke agreed to consider making changes to RAI G-1 to address what type of quality assurance program would apply to corrective actions, confirmation process, and administrative controls to cover non-safety-related structures and components subject to aging management review.

Joseph M. Sebrosky, Project Manager License Renewal and Standardization Branch Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation Docket Nos. 50-269, 50-270, and 50-287

Enclosures:

As stated (3) cc w/encls: See next page DISTRIBUTION:

See next page DOCUMENT NAME:G:\\SEBROSKY\\3-11 SUM.WPD OFFICE LA IQMB/DIPM RLSB/DRIP:PM RLSB:D NAME J,

RLatta 71/7 JSebrosk /

ClGrimes DATE

/199

/ (199

/ /99

/ 99 OFFICIAL RECORD COPY

Distribution:

Hard copy PBEF fQ Except for the attendees list in Enclosure 1, an advance copy of the handouts to EHylton this meeting summary was sent directly to the PDR on 3/15/99 Docket File PDLR RF N. Dudley, ACRS T2E2 R. Zimmerman D. Matthews C. Grimes F. Akstulewicz J. Strosnider G. Bagchi H. Brammer T. Hiltz G. Holahan S. Newberry C. Gratton R. Correia R. Latta J. Peralta J. Moore R. Weisman M. Zobler E. Hackett A. Murphy F. Cherny D. Martin W. McDowell S. Droggitis PDLR Staff H. Berkow D. LaBarge C. Ogle R. Trojanowski M. Scott C. Julian R. Architzel J. Wilson R. Gill, Duke D.. Walters, NEI r) e-V

Oconee Nuclear Station (License Renewal) cc:

Mr. J. E. Burchfield Ms. Lisa F. Vaughn Compliance Manager Duke Energy Corporation Duke Energy Corporation 422 South Church Street Oconee Nuclear Site Mail Stop PB-05E P. 0. Box 1439 Charlotte, North Carolina 28201-1006 Seneca, South Carolina 29679 Anne W. Cottingham, Esquire Ms. Karen E. Long Winston and Strawn Assistant Attorney General 1400 L Street, NW.

North Carolina Department of Justice Washington, DC 20005 P. 0. Box 629 Raleigh, North Carolina 27602 Mr. Rick N. Edwards Framatome Technologies L. A. Keller Suite 525 Manager - Nuclear Regulatory Licensing 1700 Rockville Pike Duke Energy Corporation Rockville, Maryland 20852-1631 526 South Church Street Charlotte, North Carolina 28201-1006 Manager, LIS NUS Corporation Mr. Richard M. Fry, Director 2650 McCormick Drive, 3rd Floor Division of Radiation Protection Clearwater, Florida 34619-1035 North Carolina Department of Environment, Health, and Senior Resident Inspector Natural Resources U. S. Nuclear Regulatory Commission 3825 Barrett Drive 7812B Rochester Highway Raleigh, North Carolina 27609-7721 Seneca, South Carolina 29672 Gregory D. Robison Regional Administrator, Region II Duke Energy Corporation U. S. Nuclear Regulatory Commission Mail Stop EC-12R Atlanta Federal Center P. 0. Box 1006 61 Forsyth Street, SW, Suite 23T85 Charlotte, North Carolina 28201-1006 Atlanta, Georgia 30303 Robert L. Gill, Jr..

Virgil R. Autry, Director Duke Energy Corporation Division of Radioactive Waste Management Mail Stop EC-12R Bureau of Land and Waste Management P. 0. Box 1006 Department of Health and Charlotte, North Carolina 28201-1006 Environmental Control RLGILL@DUKE-ENERGY.COM 2600 Bull Street Columbia, South Carolina 29201-1708 Douglas J. Walters Nuclear Energy Institute County Supervisor of Oconee County 1776 1 Street, NW Walhalla, South Carolina 29621 Suite 400 Washington, DC 20006-3708 W. R. McCollum, Jr., Vice President DJW@NEI.ORG Oconee Site Duke Energy Corporation Chattooga River Watershed Coalition P.O. Box 1439 P.O. Box2006 Seneca, SC 29679 Clayton, GA 30525

ATTENDANCE LIST MARCH 11, 1999, NRC MEETING WITH DUKE REGARDING SCOPING FOR THE OCONEE LICENSE RENEWAL APPLICATION NAME ORGANIZATION Robert Gill Duke Energy Corporation Steve Nader Duke Energy Corporation Rounette Nader Duke Energy Corporation Michael Semmler Duke Energy Corporation Debbie Ramsey Duke Energy Corporation Paul Colaianni Duke Energy Corporation Joe Sebrosky NRR/DRIP/PDLR Robert Prato NRR/DRIP/PDLR P. T. Kuo (part time)

NRR/DRIP/PDLR Norihisa Yuki NRR/DRIP/PDLR Steve Hoffman (part time)

NRR/DRIP/PDLR Juan Peralta NRR/DIPM/HQMB R. M. Latta NRR/DIPM/HQMB Dale Thatcher NRR/DE/EELB Paul Shemanski NRR/DE/EELB Duc Nguyen NRR/DE/EELB Jit Vora NRC/RES/DET/EMMEB Caudle Julian (via phone)

NRC/Region II George McDonald (via phone)

NRC/Region II Billy Crowley (via phone)

NRC/Region II Jerry Dozier NUS Information Services Preston Dougherty Virginia Power Alice Carson Bechtel Power John O'Donnell GSI, Inc.

Will Kenworthy GSI

Meeting with Duke Power Company Agenda A. SCOPE Duke's response to.RAIs 2.2-6 (12/1/98B), 2.6-1 (11/25/98A), 2.6-9 (11/25/98A), 2.6.1-1 (12/01/98B), 2.6.1-2 (12/01/98B), 2.6.1-3 (12/01/98B), 2.6.1-4 (12/01/98B), 2.6.7-1 (12/01/98B),

and 2.6.7-2 (12/01/98B.

B. SPECIFIC DISCUSSION TOPICS

1. Describe OSRDC effort as it applies to license renewal and its current status.

2. Provide a list of sources used to determine what SSCs satisfy Duke's definition of "Design Basis Events" that is required to include the following:

(a) Conditions of normal operation, including anticipated operational occurrences, (b) design basis accidents, (c) external events, and (d) natural phenomena for which plants must be designed to ensure functions encompassed by §50.49 (b)(1)(i) (A) through (C)

3. Provide a copy of the OSRDC specification and implementing procedures (these copies need not be docketed, they will be returned).

4. Provide the documentation of the implementation of the OSRDC process for the following SSCs:

(a) EFW (b) Low Pressure Service Water (c) Caustic Chemical Addition (d) SSF

5. Describe the role of the OSRDC process in electrical scoping.

6. Describe the electrical screening process, step 1 (Table 2.6-1, Column 2). If applicable, be prepared to discuss the intended functions used to determine if the commodity performed its intended function with moving parts or change in configuration or properties. Be prepared to provide a justification for those intended functions used as it relates to the discussion of intended function under NEI 95-10, Subsection 3.2 and 4.1.2. Be prepared to state if you used "basic component-type intended functions" in your revised scoping and screening process.

7. Describe the electrical screening process, step 2 (Table 2.6-1, Column 3). Be prepared to discuss the intended functions used to screen out a commodity group. Be prepared to discuss how you screened out component commodities using the scoping criteria under 54.4(a), especially if the OSRDC was not used to identify which electrical components meet the scoping criteria.

-2

8. The ONS structural intended functions appropriately include the following three functions:

• "provide structural and/or functional support to safety related equipment" "provide shelter/protection to safety related equipment (including radiation shielding)"

• "provide structural and/or functional support to non-safety related equipment where failure of this structural component could directly prevent satisfactory accomplishment of any of the required safety-related functions,"

Be prepared to discuss how Duke verified that every structure is included within the scope of the rule (regardless of its Class 3 rating under the CLB and the license), that provides applicable structural support, functional support, shelter, and protection (include III I equipment) to any electrical and mechanical component identified as being within the scope of the rule regardless of aging management requirements (or lack thereof) for those mechanical and electrical components. Be prepared to discuss how Duke accomplished this if the OSRDC was not used to identify which electrical components meet the scoping criteria.

NRC / Duke License Renewal Meeting March W 1999 AGENDA

1. Introduction

2. Oconee Safety Related Designation Clarification (OSRDC) Project Overview (NRC Discussion Topic #1)

3. Oconee License Renewal Mechanical 54.4 (a)(1) & (a)(2) Scoping Process Overview (NRC Discussion Topic #1)

4. Oconee License Renewal Mechanical 54.4 (a)(1) & (a)(2) Scoping Process Examples (NRC Discussion Topic #4)

• SSF Reactor Coolant Makeup System

• Chemical Addition System (Caustic Addition Portion)

• Keowee Turbine Generator Cooling Water System

• Emergency Feedwater System

• Low Pressure Service Water System BREAK

5. Oconee License Renewal Structural 54.4 (a)(1) & (a)(2) Validation Process (NRC Discussion Topic #8)

6. Oconee License Renewal Electrical Screening & Scoping Process (NRC Discussion Topics #6 and #7)

7. Oconee License Renewal Electrical Scoping Validation Process (NRC Discussion Topic #5)

8. Clarify (mark-up) 54.4 (a)(1) & (a)(2) Scoping Process information in support of Safety Evaluation and Scoping & Screening Inspection BREAK

9. Return to Item 1 above:

NRC Discussion Topics #2 (Oconee Design Basis Event Definition) and #3 (Review OSRDC documents)

10.

Wrap-up details / actions to move forward

AGENDA ITEM 2 Oconee Safety Related Designation Clarification (OSRDC) Project Overview (NRC Discussion Topic #1)

I. Initiative 1

• Obtain NRC agreement on QA-1 definition at ONS Completed:

Issued April 12, 1995 letter to NRC summarizing QA-1 definition SER received Aug. 3, 1995 II.

Initiative 2

• Research and clarify docketed mitigation strategy for Design Basis Events

• Develop event mitigation calculations

• Capture the results in a component database Completed:

Issued approved calculations documenting results 111.

Initiative 3

• Identify those components used in event mitigation not required to be QA-1 (This is the "delta" between Initiative I and Initiative 2)

Ongoing:

Results will be documented in approved calculations IV.

Initiative 4

• Develop a QA-5 program based on a subset of Appendix B 18 point criteria

• Update station directives, write/revise testing procedures Ongoing:

QA Topical revised

AGENDA ITEM 2 Oconee Safety Related Designation Clarification (OSRDC) Project Overview (NRC Discussion Topic #1)

Detailed discussion of OSRDC input to License Renewal Initiative 2 Background

• Clarify design basis (identify events, system functions, components)

• Improve level of documentation (relational database)

• Provide a structured source for scoping for regulated programs Identify all active equipment required to mitigate design basis events, using the standard 3-part definition of safety-related as the success criteria Initiative 2 Process

• Map all Maintenance Rule system functions onto flow diagrams

• Pick an event

• Identify required system functions to address each critical safety function Two uses of the identified mapped functions

-OSRDC identified active equipment for each function and populated our event mitigation database. All Mechanical and Electrical active components necessary for event mitigation were identified

-LR used the mapped functions as an input to their project

AGENDA ITEM 3 Oconee License Renewal Mechanical 54.4(a)(1) & (a)(2) Scoping Process Overview (NRC Discussion Topic #1)

Stel2 #1 Identify all mechanical flowpaths required to remain functional for successful design basis event mitigation This information came from the results of second initiative of OSRDC.

This step is described in Section 2.2.1.1(a) of the Application and in the fourth paragraph of response to RAI 2.2-6.

Step #2 Identify all physical pressure boundaries whose loss of fluid pressure boundary could impact the mechanical functions identified in Step #1 This information was generated by the License Renewal Project and documented in a QA-1 calculation.

This step is described in Section 2.2.1.1(b) of the Application.

Step #3 Identify all portions of mechanical systems whose loss of pressure boundary or structural integrity would physically interfere with the function of any essential system and component.

This information was retrieved directly from Oconee flow diagrams as Oconee Pipe Class D piping and documented in a QA-1 calculation.

This step is described in Section 2.2.1.1(c) of the Application and in response to RAIs 3.5.3-1, 3.5.6-2, 3.5.7-2, 3.5.13-2, and 3.5.14-4.

Step #4 Identify all portions of mechanical systems designated as safety-related or seismic-related piping or components that do not meet the criteria of 10 CFR 54.4(a)(1) or (a)(2).

This information was retrieved directly from Oconee flow diagrams as Oconee Pipe Classes A, B, C, or F piping not already identified as within the scope of license renewal and documented in a QA-1 calculation.

This step is described in Section 2.2.1.1(d) of the Application.

The OLRFD highlights capture the results from Steps #1, #2, #3, and #4, and represent the complete mechanical scoping evaluation boundaries for 10 CFR 54.4(a)(1) and (a)(2).

Note: OLRFD highlights also represent 10 CFR 54.4(a)(3) evaluation boundaries.

AGENDA ITEM 4 Oconee License Renewal Mechanical 54.4(a)(1) & (a)(2) Scoping Process Examples (NRC Discussion Topic #2)

Step #1 Identify all mechanical flowpaths required to remain functional for successful design basis event mitigation This information came from the results of second initiative of OSRDC.

This information is shown on the multi-colored highlighted flow diagrams. Each function is highlighted a separate color.

Step #2 Identify all fluid pressure boundaries whose loss of fluid pressure boundary could impact the mechanical functions identified in Step #1 This information was generated by the License Renewal Project and documented in a QA-1 calculation.

This information is shown on the dual-colored highlighted flow diagrams. The multi colored flowpaths are highlighted in orange. The fluid pressure boundaries are highlighted in blue.

Step #3 Identify all portions of mechanical systems whose loss of pressure boundary or structural integrity would physically interfere with the function of any essential system and component.

This information was retrieved directly from Oconee flow diagrams as Oconee Pipe Class D piping and documented in a QA-1 calculation.

This information is captured on the OLRFD highlights.

Step #4 Identify all portions of mechanical systems designated as safety-related or seismic-related piping or components that do not meet the criteria of 10 CFR 54.4(a)(1) or (a)(2).

This information was retrieved directly from Oconee flow diagrams as Oconee Pipe Classes A, B, C, or F piping not already identified as within the scope of license renewal.

This information is captured on the OLRFD highlights and documented in a QA-1 calculation.

The OLRFD highlights capture the results from Steps #1, #2, #3, and #4, and represent the complete mechanical scoping evaluation boundaries for 10 CFR 54.4(a)(1) and (a)(2).

Note: OLRFD highlights also represent 10 CFR 54.4(a)(3) evaluation boundaries.

MECHANICAL LICENSING RENEWAL SCOPING SYSTEM FUNCTIONS EXAMPLES Reactor Coolant Makeup System - DBE, FP, SBO RCM.01 Supply makeup water from the SFP to the RCS for inventory control. (DBE, FP)

RCM.02 Supply cooling water from the SFP to the RCP seals to prevent seal LOCA. (DBE, FP, SBO)

RCM.03 Provide RCS letdown capability to the SFP. (DBE, FP, SBO)

Chemical Addition System - DBE, FP, EQ, SBO CA.03 Maintain RCS pressure boundary.(DBE, SBO)

CA.05 Provide caustic addition to sump. (DBE)

CA.06 Maintain containment integrity.(DBE, SBO)

CA.07 Provide manual sampling capability via Post-Accident Liquid Sampling RCS sample line.(FP)

Turbine Generator Cooling Water System - DBE, FP WL.01 Provide cooling water to the following: - Turbine Guide Bearing Oil Cooler - Turbine Packing Box - Generator Thrust Bearing Coolers - Generator Air Coolers. Back to penstock, including screens. (DBE, FP)

Emergency Feedwater System - DBE, FP, EQ, ATWS EFW.01 Provide an assured source of feedwater to the steam generators to remove decay heat until the LPI system may be operated or the main feedwater system is restored. (DBE, FP, ATWS)

EFW.04 Provide isolation of EFW flow following a main steam line break or SG Tube rupture or to prevent dilution of the RB sump. (DBE)

EFW.05 Provide shell cooling of an isolated SG during plant cooldown when the main feedwater system is unavailable. (DBE)

EFW.06 Prevent EFW pump runout and steam generator tube flow-induced vibration.(DBE)

EFW.07 Isolate to prevent uncontrolled feedwater flow to steam generators during use of the SSF ASW pump.(FP)

Low Pressure Service Water System - DBE, FP, EQ, SBO, D LPS.01 Provide cooling water from the CCW intake piping to the following equipment: - Reactor Building Cooling Units - Decay Heat Removal Coolers - HPI Pump Motor Bearing Coolers - Turbine Driven EFW Pump Bearing Cooling Jackets - Motor Driven EFW Pump Motor. (DBE, FP)

LPS.08 Maintain containment integrity. (DBE, SBO)

AGENDA ITEM 9 NRC Discussion Topic #2 Design Basis Events

• Definition of Design Basis Events came from 10CFR50.49

• Oconee was licensed to its own unique set of DBEs

• Oconee DBEs are Chapter 15 events

• This definition was used and approved in our 10CFR50.49 submittal Chapter 15 Events Loss of Offsite Power Turbine Trip (included in our new topical, under review)

Loss of Electric Power Large Break Loss of Coolant w/ LOOP Steam Generator Tube Rupture Main Steam Line Break Fuel Handling Accident.

Moderator Dilution Accident Post Accident Hydrogen Control Control Rod Misalignment Cold Water Accident Locked Rotor/Sheared Shaft Loss of Coolant Flow Startup Accident Small Break Loss of Coolant Accident Maximum Hypothetical Accident Rod Ejection Accident Uncompensated Reactivity Change Waste Gas Tank Rupture Rod Withdrawal Accident Additional events are also considered using risk based input Additional Scoping Events Loss of Main Feedwater Turbine Building Flood Tornado Seismic External Floods and Groundwater Snow and Ice

2.2 IDENTIFICATION OF SYSTEMS, STRUCTURES, AND COMPONENTS WITHIN THE SCOPE OF LICENSE RENEWAL 2.2.1 REVIEW TO CRITERIA IN §§54.4(a)(1) AND (a)(2) 2.2.1.2 Structures

[Insert at end of Section]

In order to validate the list of structures that satisfy the criteria contained in §§54.4(a)(1) and (a)(2), a review was performed to ensure that all structures which contain mechanical and electrical components that satisfy the criteria contained in §§54.4(a)(1) and (a)(2) were identified. The review verified that all structures that contain mechanical and electrical components that satisfy the criteria contained in §§54.4(a)(1) and (a)(2) of the Rule have been identified.