ML20071H798

Forwards Response to RAI Re Application for Amend to TS 3/4.4.5, Steam Generators. RAI Withheld

ML20071H798
Person / Time
Site:	Braidwood
Issue date:	07/13/1994
From:	Saccomando D COMMONWEALTH EDISON CO.
To:	Russell W NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
Shared Package
ML19304C393	List: ML20071H798 NRC-94-4197, Forwards NDS-TAP-3079, Response to Rai,Items 2B-2G in Support of Braidwood Unit 1 SG Tube Interim Plugging Criteria. Response Withheld (Ref 10CFR2.790)
References
NUDOCS 9407210179
Download: ML20071H798 (2)

Text

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[ Commonwrith Edison t- A < ' 1400 Opus Place Downers Grove. Illinois 60515 j

'~~'[ July 13,1994 i l

l Mr. William T. Russell, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Document Control Desk

Subject:

Response to Request for Additional Information Relating to the Request to Amend Technical Specification Section 3/4.4.5,

" Steam Generators" Braidwood Station Unit 1 NPF-72; NRC Docket No. 50-456

References:

1) N. J. Liparulo (Westinghouse) letter to B. Sheron (NRC) dated July 13,1994, addressing the proprietary nature of Westinghouse supplied information

2) R. Assa letter to D. Farrar dated July 7,1994, transmitting a Request for Additional Information

3) D. Saccomando letter to W. Russell, dated June 20,1994, transmitting a request to amend Technical Specification Section 3/4.4.5, " Steam Generators"

Dear Mr. Russell:

Reference 2 (attached) transmitted a Nuclear Regulatory Commission Request for j Additional Information pertaining to Commonwealth Edison Company's request to I amend Section 3/4.4.5 of Technical Specifications for Braidwood Unit 1, as transmitted in Reference 3.

Attachment 1 provides the requested information regarding primary-to-secondary leakage monitoring. Attachments 2 and 3 address the questions pertaining to the tube support plate deflection analysis.

Please note that Attachments 2 and 3 contain proprietary information as specified in the attached Westinghouse letter (NTD-NRC-94-4197) dated July 13,1994.

This letter defines how Westinghouse Corporation will comply with the requirements of 10 CFR 2.790. Accordingly, it is respectfully requested that the information which is proprietary to Westinghouse be withheld from public disclosure.

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Mr. W. '/. R'ussell 2 July 13,1994 Correspondence with respect to the proprietary aspects of Attachments 2 and 3 should be addressed to N. J. Liparulo, Manager of Nuclear Safety & Regulatory Activities, Westinghouse Electric Corporation, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.

If you have any questions concerning this correspondence please contact this office.

Sincerely, o f // . W h m s.) h r enise M. Saccomando Nuclear Licensing Administrator Attachments cc: R. Assa, Braidwood Project Manager-NRR S. Dupont, Senior Resident Inspector-Braidwood B. Clayton, Branch Chief-Region III Office of Nuclear Facility Safety-IDNS I

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i s>O M Gli pe t UNITED STATES l 8 E NUCLEAR REGULATORY COMMISSION l

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• July 7, 1994 I Docket No. STN 50-456 1

Mr. D. L. Farrar Manager, Nuclear Regulatory Services Commonwealth Edison Company Executive Towers West III, Suite 500. .

1400 OPUS Place Downers Grove, Illinois 60515  !

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION (TAC NO. MS9116)

By letter dated June 20, 1994, Commonwealth Edison Company (Comed) requested a revision to Technical Specification (TS) 3/4.4.5, " Steam Generators." The revision would allow Braidwood, Unit 1, to continue operations pass the 100 day limit imposed by Amendment No. 50 issued on May 7 1994. Prior to the amendment request, by letter of May 4,1994 ComEdsubmittedinformation concerning primar Based on our review of yoursubmittals,y-to-secondaryleakagemonitoring.

we have determined that we need additional information to continue our review. The enclosed list of questions identifies the information needed. The questions are in two parts: part one seeks to clarify the information you provided regarding the leakage monitoring and part two addresses the tube support plate deflection analysis. Please review these questions and submit your response by July 13, 1994. The staff requests your prompt response to these questions in order to support your requested date for completion of this review.

The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under P.L.96-511.

Should you have any further questions regarding this request, please contact me at (301) 504-1391.

Sincerely, I

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Ramin R. Assa, Acting Project Manager '

Pro. ject Directorate III-2 Division of Reactor Projects -III/IV Office of Nuclear Reactor Regulation

Enclosure:

Request for Additional Information cc w/ enclosure:

See next page Cd'i l

Mr. D. L. Farrar Braidwood Station Commonwealth Edison Company Unit I cc:

Mr. William P. Poirier Chairman Westinghouse Electric Corporation Will County Board of Supervisors Energy Systems Business Unit Will County Board Courthouse Post Office Box 355, Bay 236 West Joliet, Illinois 60434 Pittsburgh, Pennsylvannia 15230 Ms. Lorraine Creek Joseph Gallo Rt. 1, Box 182 Gallo & Ross Manteno, Illinois 60950 1250 Eye St., N.W., Suite 302 Washington, D.C. 20005' Attorney General 500 South 2nd Street Regional Administrator Springfield, Illinois 62701 U. S. NRC, Region III 801 Warrenville Road Michael Miller, Esquire Lisle, Illinois 60532-4351 Sidley and Austin One First National Plaza Ms. Bridget Little Rorem Chicago, Illinois .60690 Appleseed Coordinator 117 North Linden Street George L. Edgar Essex, Illinois 60935 Newman & Holtzinger, P.C.

1615 L Street, N.W.

Howard A. Learner Washington, D.C. 20036 Environmental Law and Policy Center of the Midwest Illinois Dept. of Nuclear Safety 203 North LaSalle Street Office of Nuclear Facility Safety Suite 1390 1035 Outer Park Drive Chicago, Illinois 60601 Springfield, Illinois 62704 U.- S. Nuclear Regulatory Commission Commonwealth _ Edison Company Braidwood Resident Inspectors Office Braidwood Station Manager Rural _ Route #1, Box 79 Rt. 1, Box 84 Braceville, Illinois 60407 Braceville, Illinois 60407 Mr. Ron Stephens EIS Review Coordinator Illinois Emergency Services U.S. Environmental Protection Agency and Disaster Agency 77 W. Jackson Blvd.

110 East Adams Street Chicago, Illinois 60604-3590 Springfield, Illinois 62706

ENCLOSURE RE0 VEST FOR ADDITIONAL INFORMATION TO SUPPLEMENT RE0 VESTED TECHNICAL SPECIFICATION AMENDMENT COMMONWEALTH EDISON COMPANY BRAIDWOOD STATION. UNIT 1

1. The response offered in the attachment to Comed's letter of May 4,1994, addressed the expected impact of installing N-16 steam line monitors.

The response discussed existing radiation monitoring capabilities considered equivalent to N-16 monitors. To more clearly compare the monitoring methods, please address the following:

a. Furnish a comparison of the sensitivity of the steam jet air ejector / gland steam process radiation monitor and the N-16 monitor considered under the proposal to install N-16 monitors discussed in the May 4, 1994, letter. Sensitivity should be characterized by the minimum detectable primary-to-secondary leakage levels compared at the same power level, the response time of the instruments, and the delay involved from instrument leakage response to indication available in the control room. Also contrast the ability of the monitoring methods to differentiate the leaking steam generator (SG) in terms of the time from leak initiation to indication available to the operators.

b. Considering the detection methods covered in 1(a), discuss the ability to furnish leak rate trending information to the control room operators.

c. Explain how the portable N-16 monitor is to be used during a primary-to-secondary leak event. Include what conditions prompt its use, how the instrument is calibrated, the time required to obtain an indication from the time an order is issued to use the portable monitor. Also furnish a sensitivity comparison of this device to the permanently installed monitoring equipment as discussed under 1(a).

d. Discuss, in detail, the method used to estimate primary-to-secondary leak rate from area radiation monitors and process radiation monitor indications.

e. Regarding the monitoring methods discussed in 1(a) and 1(c), compare the work load encountered by the operators during a tube failure event. Discuss sources of errors and chances of operator faults for the monitoring alternatives.

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2. The first step in the tube support plate (TSP) deflection analysis is to predict the hydraulic loads on the TSPs during a limiting event. The l TRANFLO code was used to calculate the loads for a steam line break (SLB) occurring from hot standby and normal operating conditions for the D3 SG design and from operating conditions for the D4 design (it is our understanding that further analysis for the D4 design is underway). In order to take any credit for the TSP deflection analysis, more information is needed to qualify the results of the hydraulic loading calculations.

a. Provide detailed information on the noding used in the TRANFLO model, i.e., for the noding used in WCAP-14046, give volumes and junction flow areas, loss coefficients and flow areas they are based on, and heat slabs in the model. Supplement this with detailed diagrams of the D4 SG internal layout, showing dimensions and all internal components. Provide details of the initial secondary flow distribution for the SLB calculation.

b. Explain, in further detail, why the secondary side SG water levels chosen for the analyses are most conservative. Were sensitivity studies performed to determine the effect of varied water level?

c. Provide complete documentation on the TRANFLO code, including all changes made since WCAP-8821, "TRANFLO Steam Generator Code Description" (September 1976) was issued. Include experimental data used for verification and results of TRANFLO simulations used in the verification.

d. Discuss the assumptions and uncertainties associated with the TRANFLO model . Include an assessment of the level of uncertainty of the differential pressures depicted in the graphs in Chapter 4 of WCAP-14046.

e. Discuss the extent to which pressure differentials on the TSPs may be asymmetric about the SG centerline.

f. Does TRANFLO account for acoustic effects at the initiation of the SLB event? If not, what is the expected magnitude of such an effect compared to the differential pressures determined by TRANFLO?

g. Page 4-10 of WCAP 14046 states that " pressures are scaled" and that

" pressure drops were modified" in the hydraulic analysis for application to the structural analysis. Please explain in detail the procedure referred to by these statements.

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