ML021630270

Public Meeting with Firstenergy Nuclear Operating Company (FENOC) and Their Consultants Regarding On-Going Pressurized Thermal Shock Rulemaking Effort

ML021630270
Person / Time
Site:	Beaver Valley
Issue date:	06/11/2002
From:	Woods H Office of Nuclear Regulatory Research
To:
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Download: ML021630270 (17)

Text

June 11, 2002 LICENSEE:

FirstEnergy Nuclear Operating Company (FENOC)

FACILITY:

Beaver Valley Power Station (BVPS), Unit 1

SUMMARY

OF MAY 14, 2002, PUBLIC MEETING WITH FIRSTENERGY NUCLEAR OPERATING COMPANY (FENOC) AND THEIR CONSULTANTS REGARDING ON-GOING PRESSURIZED THERMAL SHOCK (PTS)

RULEMAKING EFFORT

Background

The Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research (NRC Research), staff is currently conducting an analysis of the risk due to PTS at U.S. Pressurized Water Reactors (PWRs).

The results will be used as part of the bases for a subsequent evaluation (and possible change) of the PTS rule, Title 10 of the Code of Federal Regulations, Section 50.61. BVPS Unit 1 is one of four PWRs that have volunteered to be evaluated as part of the analysis.

Discussion On May 14, 2002, members of the NRC Research staff met in a public meeting at the BVPS in Shippingport, Pennsylvania, with representatives of FENOC, Westinghouse Electric Co. (W),

Sandia National Laboratories (SNL), Science Applications International Corp. (SAIC), and Information Systems Laboratory (ISL), to discuss preliminary results of the NRC Research staffs analysis of the risk at BVPS Unit 1 due to hypothetical PTS events. Enclosure 1 is the agenda and Enclosure 2 is the list of attendees.

The meeting started with an NRC Research staff presentation of the overall organization of the joint NRC Research & Industry PTS risk analysis effort, showing how the Probabilistic Risk Analysis (PRA), Human Reliability Analysis (HRA), Thermal Hydraulic (TH), and Probabilistic Fracture Mechanics portions of the analysis will be utilized, along with their associated uncertainty analyses, to produce the final PTS-related risk for each of the four plants included in the study (Oconee, Beaver Valley, Palisades, and Calvert Cliffs).

The NRC Research staff presentation also discussed the major objectives of the meeting, which were to present draft results of the preliminary BVPS Unit 1 PRA, HRA, and TH analyses, and obtain the FENOC staffs comments and suggestions. The presentation indicated that the preliminary analyses were performed in a somewhat conservative way, which would CONTACT:

H. Woods, RES 301-415-6622

FirstEnergy Nuclear Operating Company nevertheless be able to identify the PTS-risk-significant areas and thus allow subsequent efforts to concentrate on making the PRA analysis of those areas more realistic. This process saves the expenditure of scarce resources in areas that do not contribute significantly to PTS risk. is the NRCs and NRC contractors slides used during this discussion.

Next, the principal PRA/HRA contractors (from SNL and SAIC) discussed the preliminary results, stressing areas identified by the analyses that contribute significant PTS risk, and inviting comments from the FENOC and W staffs, particularly about ways those parts of the analyses might be made more complete and realistic.

In discussions that followed, the FENOC staff expressed general agreement with the models and techniques used by the staff and their contractors in the analyses. However, in keeping with the primary purpose of the meeting (i.e., to discuss ways the analysis results might be made more complete and realistic) the FENOC staff offered the following preliminary comments:

1) During feed and bleed, only two high-head safety injection (HHSI) pumps can operate. A third (standby) pump cannot be loaded to a bus with an operating HHSI pump. TH calculations should be examined to ensure that only two pumps are operating.

2) The following scenario should be considered: the steam dump valve down stream of the main steam isolation valves (MSIVs) opens resulting in cool down and depressurization of the primary reactor coolant system. HHSI starts. MSIVs close, but HHSI continues to run resulting in repressurization. Repressurization causes a pressurizer safety relief valve (SRV) to open.

The SRV sticks open.

3) For loss of feedwater sequences, both the dedicated auxiliary feedwater (AFW) pump and the condensate booster pumps should be included in the model. Procedures applicable to each sequence (e.g., RT1-2 sequence #9) should be used to determine which pump should be used first.

4) On loss of red or white 120 VAC bus, only one HHSI pump is available. Determine if this is modeled correctly in the PRA and TH calculations (the same issue applies to loss of 125 VDC buses).

5) Determine whether the loss of a 4 kV/480 VAC bus initiator should be added to the model.

If so, only one HHSI pump would be left.

6) For AFW, on loss of blue or yellow 120 VAC bus, only partial flow is available to steam generators. Determine if effects of this need to be included in the models.

These comments will be considered by the NRC staff and their contractors, along with any additional comments received from the FENOC or W staffs after their further review.

Summary, Action Items, and Agreements The FENOC staff volunteered to provide additional, more detailed comments in writing to the NRC Research staff during June 2002, providing justifications for any modifications they might

FirstEnergy Nuclear Operating Company request to the analysis. The NRC Research staff and its contractors will review any requested changes, and will modify their analyses to reflect any changes they find to be acceptable.

This meeting was not an inspection. Instead, it was an information exchange meeting with a licensee who has volunteered to cooperate with NRC Researchs PTS evaluation effort. As such, no open items were identified that require future actions or NRC approvals. No requests or agreements resulting from the meeting are required to be met, nor are they enforceable in any way.

The NRC Research staff appreciates the cooperation and suggestions that were made by the FENOC staff. NRC Research understands that it is very much dependent upon such voluntary cooperation to obtain the information and feedback needed to reach the joint NRC and nuclear industry goal of achieving a PTS analysis of BVPS as it is actually built and operated. We look forward to continued interactions with FENOC so that we can achieve that mutually desired goal.

Hugh W. Woods, Senior Task Manager Probabilistic Risk Analysis Branch Division of Risk Analysis and Applications Office of Nuclear Regulatory Research Docket No. 50-334

Enclosures:

1. Agenda

2. List of Attendees

3. NRC's and NRC contractors' slides used at the meeting cc w/encls: See next page HWoods SNewberry DBessette MCunningham TBergman, EDO RI ACRS SRichards RLaufer DCollins MOBrien JRogge, RI RConte, RI DScrenci, OPA RI DKern, RI DMcCain NSiu, RES BPlatchek, RI PUBLIC PDI-1 RF OGC JZwolinski/TMarsh DOCUMENT NAME:g:\\pts\\2ndMtgMins.wpd OAR in ADAMS? (Y or N) Y ADAMS ACCESSION NO.: TEMPLATE NO. RES-Publicly Available? (Y or N) Y DATE OF RELEASE TO PUBLIC SENSITIVE? N To receive a copy of this document, indicate in the box: "C" = Copy without enclosures "E" = Copy with enclosures "N" = No copy OFFICE DRAA/PRAB DRAA/PRAB DRAA NRR/PM/

PDI-1 NRR/SC/

PDI-1 NAME H. Woods*

M. Cunningham*

S. Newberry*

D. Collins*

R. Laufer*

DATE 05/22/02 05/23/02 05/27/02 06/11/02 06/11/02 (RES File Code) RES -2C-1A2

• See previous concurrence

Mary OReilly, Attorney FirstEnergy Nuclear Operating Company FirstEnergy Corporation 76 South Main Street Akron, OH 44308 FirstEnergy Nuclear Operating Company Regulatory Affairs/Corrective Action Section Larry R. Freeland, Manager Beaver Valley Power Station Post Office Box 4, BV-A Shippingport, PA 15077 Commissioner James R. Lewis West Virginia Division of Labor 749-B, Building No. 6 Capitol Complex Charleston, WV 25305 Director, Utilities Department Public Utilities Commission 180 East Broad Street Columbus, OH 43266-0573 Director, Pennsylvania Emergency Management Agency 2605 Interstate Dr.

Harrisburg, PA 17110-9364 Ohio EPA-DERR ATTN: Zack A. Clayton Post Office Box 1049 Columbus, OH 43266-0149 Dr. Judith Johnsrud National Energy Committee Sierra Club 433 Orlando Avenue State College, PA 16803 L. W. Pearce, Plant Manager (BV-IPAB)

FirstEnergy Nuclear Operating Company Beaver Valley Power Station Post Office Box 4 Shippingport, PA 15077 Bureau of Radiation Protection ATTN: Larry Ryan P O Box 2063 Harrisburg, PA 17120 Mayor of the Borough of Shippingport P O Box 3 Shippingport, PA 15077 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Resident Inspector U.S. Nuclear Regulatory Commission Post Office Box 298 Shippingport, PA 15077 FirstEnergy Nuclear Operating Company Beaver Valley Power Station ATTN: M. P. Pearson, Director Services and Projects (BV-IPAB)

Post Office Box 4 Shippingport, PA 15077 FirstEnergy Nuclear Operating Company Beaver Valley Power Station Mr. B. F. Sepelak Post Office Box 4, BV-A Shippingport, PA 15077 Mr. Mark B. Bezilla Senior Vice President FirstEnergy Nuclear Operating Company Beaver Valley Power Station Post Office Box 4 Shippingport, PA 15077

AGENDA MEETING WITH FIRSTENERGY NUCLEAR OPERATING COMPANY (FENOC)

AND THEIR CONSULTANTS REGARDING ON-GOING PRESSURIZED THERMAL SHOCK (PTS) RULEMAKING EFFORT May 14, 2002 - 9:00 - 4:00 PM 9:00-9:30 Introduction/Overview H. (Roy) Woods (NRC)

Introduction of Attendees (NRC and FENOC)

Purpose/Goals of Meeting Status/Schedule of PTS Program 9:30-11:00 Presentation of Probabilistic Risk Donnie Whitehead (SNL)

Analysis Approach and Preliminary Results Alan Kolaczkowski (SAIC) 11:00-12:00 Discussion All (NRC and FENOC) 12:00-1:00 Lunch 1:00-3:30 Continuation of Discussion All (NRC and FENOC) 3:30-4:00 Summary (Action Items, Commitments)

All (NRC and FENOC)

LIST OF ATTENDEES MEETING WITH FIRSTENERGY NUCLEAR OPERATING COMPANY (FENOC)

AND THEIR CONSULTANTS REGARDING ON-GOING PRESSURIZED THERMAL SHOCK (PTS) RULEMAKING EFFORT MAY 14, 2002 NAME ORGANIZATION David Bessette NRC/RESEARCH Hugh (Roy) Woods NRC/RESEARCH Alan Kolaczkowski Science Applications International Corp. (SAIC)

Donnie Whitehead Sandia National Laboratories Robert Beaton Information Systems Laboratory Dennis Weakland FENOC Chris Hynes FENOC Ken Frederick FENOC Bill Etzel FENOC Bruce Bishop Westinghouse Electric Corp.

Eric Frantz Westinghouse Electric Corp.

Barry Sloane Westinghouse Electric Corp.

SLIDES USED AT THE MEETING WITH FIRSTENERGY NUCLEAR OPERATING COMPANY (FENOC) AND THEIR CONSULTANTS REGARDING ON-GOING PRESSURIZED THERMAL SHOCK (PTS) RULEMAKING EFFORT

PRA/HRA & TH for PTS Rule Revision Roy Woods Office of Nuclear Regulatory Research U.S. Nuclear Regulatory Commission Presented to FirstEnergy Nuclear Operating Co. (FENOC) at Beaver Valley Power Station (BVPS)

May 14, 2002

FirstEnergy Nuclear Operating Company Use Public Meetings to Identify Open Technical Questions in:

--Identify and Bin PTS Events (PRA)

--Thermal Hydraulics

--Probabilistic Fracture Mechanics

--Overall Uncertainty Analysis Use Public Meetings to Identify Areas in 10CFR 50.61 that need Re-assessment (RG 1.99 Rev.)

--Embrittlement Correlations

--Margin Terms, etc.

Collect Information, Develop Methods, Do Specific Analyses, Involve Public, to

--Resolve Open Questions

--Involve PRA in All Aspects Identify & Bin Events (PRA)

--Use IPTS 3-plant study

--Update plant-specific PRAs, if available

--Update Events Frequencies (INPO, plant info, etc.)

Thermal Hydraulics

--Use expert panel and

--Limited TH analyses to estimate (1) Effect of TH improvements (2) Uncertainty bounds in TH results Probabilistic Fracture Mechanics

--Revise Flaw Distributions

--Revise Embrittlement Correlations

--Revise Fracture Toughness Models

--Material Property Variability

--Develop Up-to-date Fluence Maps, etc.

Re-assess PTS Risk Acceptance Criterion

--Base on Risk Informed Guidance

--Consider LERF, Effect on Containment

--Develop Commission Papers Public Meetings to Gain Understanding on Developed Methods and Input Parameters Calculate Vessel Fracture Frequency

--Mean Value and Variance

--Sensitivity & Uncertainty Analyses

--Evaluate IPTS and Other Plants

--Evaluate SECY 82-465 Analyses

--Evaluate Effect on Containment Re-evaluate PTS Screening Criterion

--Use Vessel Fracture Frequency

--PTS Risk Acceptance Criterion

--Generic Sensitivity Analyses Results Staff Develops Proposed Changes To 50.61 Areas. Potentially Use

--Fully Participatory Rule Making with Public Involvement Public Meetings to Resolve Outstanding Issues PROPOSE TECHNICAL BASIS FOR REVISION TO 10 CFR 50.61

--Specific Regulatory Approach

--Risk Informed

--Can it be Performance Based?

Development of Technical Basis to Revise PTS Rule 10 CFR 50.61 PRA/HRA Objective Support development of technical basis for revised rule

Ensure overall process is coherent, risk-informed



Appropriate integration of T/H, PFM, and PRA/HRA



Consistent treatment of uncertainties



Support development of screening criteria



Derivation of embrittlement criteria from risk figures of merit



Criteria for risk figures of merit



Update old PTS/PRA studies



Reflect changes to study plants



Reflect changes to PRA state of the art, knowledge base



Update HRA



Address other plants Expectation: PFM provides most of the margin Overall Analysis Framework Overall PTS/PRA/HRA Analysis Approach

Estimate PTS-induced through-wall crack frequencies (TWCFs) for 4 plants, including uncertainties



Develop PTS/PRA/HRA models for Oconee and Beaver Valley



Review PTS/PRA/HRAs for Calvert Cliffs and Palisades



Resolve inconsistencies, generalize results to population

Develop TWCF vs. RTPTS relationship, e.g.,

PTS/PRA/HRA Analysis Status

Oconee



Kickoff meeting: March, 2000



Initial PRA/HRA & TH results: December, 2000



Review meeting at Duke Energy: January, 2001



Model revised, preliminary TWCF: Dec., 2001



Final TWCF: late May, 2002

Beaver Valley



Kickoff meeting: July, 2000



Initial PRA/HRA & TH results: April, 2002



Review meeting at FENOC: May 14, 2002



TWCF results: June, 2002

Palisades



Kickoff meeting: March, 2001



HRA Quant. meeting Nov., 2001



Initial PRA/HRA & TH results: April, 2002



TWCF results: June or July, 2002

Calvert Cliffs



Early meeting August, 2001



Kickoff meeting June 5-7, 2002



Initial results: TBD



TWCF: TBD Meeting Objectives

Present draft results of PTS PRA/HRA and TH analysis for Oconee

Obtain feedback on analysis results Include in the package so they are an official part of these Public Meeting Minutes the slides in the two.pdf files as follows (they're on the G drive).

2ndMtgSldsRB.pdf 2ndMtgSldsAK&DW.pdf Hardcopies of these two files follow. However, I do not want the hardcopies to be scanned - I want the.pdf files to be part of the package that's available on ADAMS with the preceeding file.

PLEASE DELETE THIS PAGE FROM THE PACKAGE - ITS A NOTE TO PATTY OR DANIELLE