ML20003H030
| ML20003H030 | |
| Person / Time | |
|---|---|
| Site: | Zimmer |
| Issue date: | 04/23/1981 |
| From: | Tedesco R Office of Nuclear Reactor Regulation |
| To: | Borgmann E CINCINNATI GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8105040581 | |
| Download: ML20003H030 (6) | |
Text
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8 NUCLEAR REGULA10RY COMMISSION
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Docket No. 50-358 The Cincinnati Gas & Electric Company ATTN: Mr. Earl A. Borgamann Vice President, Engineering P. O. Box 960 Cincinnati, Ohio 45201
Dear Mr. Borgmann:
Subject:
Request for Additional Information - Wm. Zimmer Nu: lear Power Station - Licensing Review Group Issues In order to complete our Reactor Systems review we will need your response to the enclosed requests for additional infonnation. Most of the items were identified previously during the BWR Licensing Review Group (LRG) activities on the LaSalle Docket. We expect similar resolution on the Zimmer Docket. Please advise us when you will respond to the enclosed requests.
W S *Owi Robert L. Tedesco, Assistant Director for Licensing Division of Licensing
Enclosure:
As stated cc: See next page 4
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s Mr. Eari A. Borgmann
~Vice President - Engineering Cincinnati Gas & Electric Company P. O. Box 960 Cincinnati, Ohio 45201 Troy B. Conner, Jr., Esq.
Leah S. Kosik, Esq.
cc:
Conner, Moore & Corber 3454 Cornell Place 1747 Pennsylvania Avenue, N.W.
Cincinnati, Ohio 45220
'l Washington, D.C.
20006 Mr. William J. Moran W. Peter Heile, Esq.
General Counsel Assistant City Solicitor Room 214, City Hall Cincinnati Gas & Electric Company Cincinnati, Ohio 45220 P. O. Box 960 Cincinnati, Ohio 45201 John O. Woliver, Esq.'
Mr. William G. Porter, Jr.
Clermont County Community Council Box 181 Porter, Stanley, Arthur and Platt Batavia, Ohio 45103 37 West Broad Street firs. Mary Reder Columbus, Ohio 43215 Box 270, Rt. 2 Mr. James 0. Flynn, Manager California, Kentucky 41007 Licensing Environmental Affairs Cincinnati Gas & Electric Company Andrew B. Dennison, Esq.
P. O. Box 960 200 Main Street Batavia, Ohio 45103 Cincinnati, Ohio 45201 David Martin, Esq.
Robert A. Jones, Esq.
Office of the Attorney General Prosecuting Attorney of Clermont 209 St. Clair Street County, Ohio First Floor 154 flain Street Batavia, Ohio 45103 Frankfort, Kentucky 40601 Dr. Frank F. Hooper Resident Inspector /Zimmer School of Natural Resources RF0 1, P. O. Box 2021 U. S. Route 52 University of Michigan Moscow, Ohio 45153 Ann Arbor, Michigan 48109 Mr. John Youkilis Charles Bechhoefer, Esq., Chairman Atomic Safety & Licensing Board Panel Office of The Honorable William Gradison U.S. Nuclear Regulatory Commission United States House of Representatives Washington, D. C.
20515 Washington, D.C.
20555 Mr. Glenn 0. Bright Atomic Safety & Licensing Board Panel
' O.S. fluclear Regulatory Commission Washington, D.C.
20555
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e LRG Issue RSB-7 Shutdown Unintentionally of the Reactor Core Isolation Cooling System (5.4.1)
"Show how the design of the RCIC protection system prevents unintentional shutdown of the system, when the system is required, because of spurious ambient temperature signals from areas in and around the system (especially in the RCIC pump room).
LRG Issue (RSB-8) Residual Heat Removal System (5.4.2)
"Section 15.1.27 of ZPS-1 FSAR considered alternate shutdown cooling methods in the event the residual heat removal (RHR) system in the suction line may
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not be used because of valve failure.
In the analysis, valves in the automatic depressurization system (ADS) were used to transfer fluid (steam, water or a combination of.these) from the reactor vessel to the suppression pool.: The RHR system removes the added heat by cooling water removed from the suppression pool and injecting it into the reactor vessel.
We require that you perform a test or cite previous test results to demonstrate that the ADS valves can discharge the fluid flow under the most limiting con-ditions when the fluid is all water. Show that this alternate method is a viable means of shutdown cooling by comparing the system hydraulic losses with the available pump head.
Hydraulic losses should be provided for each system component and, wherever possible, should be derived from experimental results."
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% 4 LRG Issue RSB-12 (5.4.2)
"Show that the air supply to operate the ADS valves is sufficient in the event of:
1.
Small LOCA's.
2.
ADS valve system used as an alternate cooling method, because of valve failure in the RHR suction line.
3.
Seismic event with no credit for non-seismic components and structures.
The evaluation should cover the total period during which ADS valve system operates or may be required to operate.
Identify the core cooling mode which is used following completion of ADS operation."
't LRG' Issue RSB-16 LOCA Analysis (6.3.4)
"You have analyzed the effect on the DBA-LOCA of instantaneous closure of the flow control valve (FCV) in the unbroken loops, in, SAR Appendix S,'Section E
i 3.1.2.
This overly conservative result indicated an increase in peak clad 0
4 temperature (PCT) of 300 F which, if added to the DBA-LOCA PCT, would be in excess of the maximum PCT criterion of 10 CFR 50.46. Provide an analysis showing the effect of realistic maximum FCV closing rate upon the DBA, indicate i
l which single failure of ESF was taken and discuss the details of the analysis and results."
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- 1 LRG Issue RSB-17 Operator Action (6.3 A)
" Provide the following information related to pipe cracks in moderate energy lines outside containment associated with the RHR system when the plant is in a shutdown cooling mode.
(1) Provide the discharge rate from pipe cracks for the systems outside containment used to maintain core cooling. This value should be consistent with the requirements of SRP 3.6.1 and BTP APCSB 3-1.
(2) Determine the time frame available for recovery based on these discharge rates and their effect on core cooling.
(3) Describe the alarms available to alert the operator to the event, the recovary procedures to be utilized by the operator, and the time available for operator action A single failure criterion consistent with SRP 3.6.1 and BTP ABCSB 3-1 should be applied in the evaluation of the recovery procedures utilized."
'LRG Issue RSB-19 Failure of the Feedwater Controller (15J
'The calculated consequences for the Loss of Feedwater Heating (LFWH) event are currently based on the maximum feedwater (FW) temperature reduction which could be associated with the loss of a single feedwater heater string.
For Zimmer, the
' loss of a single FW heater string results in a temperature drop no greater than l
100 F, which is used in the licensing basis LFWH analysis. As indicat'ed in the l!
plant's FSA8, the 100 F assumption stems from the maximum loss of feedwater heating capability which could result from the worst malfunction of a single valve within the FW heating system, i.e., spurious opening or spurious closure of one valve. Thus, the severity of the LFWH event is based on a single mechanical i
component malfunction.
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j' "However, an actual FW temperature transient which occurred at a domestic l
BWR demonstrated that a single electrical compunent failure, e.g., circuit II breaker-trip (of a motor control center) could precipitate an even more if l)l severe FW temperature transient. The subject electrical equipment mal.
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-function, which temporarily caused a complete loss of all FW heating due if to total loss of extraction steam resulting in a FW temperature drop of about 150*F. Accordingly, the staff requests that Zimmer either (1) submit a suffi-
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ciently detailed failure modes and effects analysis (FMEA) to demonstrate the t
adequacy of a 100*F feedwater temperature reduction relative to a single electrical malfunction or (2) submit calculations using a limiting FW tempera-ture drop which clearly bounds current operating experience."
Available Net Positive Suction Head i
NPSH _ values given in ECCS process diagrams are not complete with pressure, temperature and elevation data applicable to Zimmer.
Identify the operating modes which give the limiting NPSH requirements for ECCS pumps and RCIC pump.
Provide a table indicating the calculated and required NPSH for ECCS pumps and RCIC pump.
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