ELV-05103, Suppls 920731 Application for Amend to Licenses NPF-68 & NPF-81,adding New TS for Feedwater Isolation Sys.Suppl Submitted for Consistency W/Rev 0 to NUREG-1431 Re STS for Westinghouse Plants,Issued by NRC on 920928
| ML20128B080 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 01/22/1993 |
| From: | Mccoy C GEORGIA POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20128B085 | List: |
| References | |
| RTR-NUREG-1431 ELV-05103, ELV-5103, NUDOCS 9302020394 | |
| Download: ML20128B080 (7) | |
Text
I e rr n
y Pon Otke Bon 1W5 hD hr i
k L
C. K. McCoy Georgia Power
$N$$ ~"
ov mwnpewc sstem January 22, 1993 ELV-05103 002752 Docket Nos. 50 424 50-425 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen:
V0 GILE ELECTRIC GENERATING PLANT REVISION TO REQUEST TO REVISE TECHNICAL SPECIFICATIONS
{
ADDITION OF FEEDWATER ISOLATION SYSTEMS By letter ELV-03723 dated July 31, 1992, Georgia Power Company requested that a new Technical Specification for feedwater isolation systems be added for the Vogtle Electric Generating Plant (VEGP).
On September 28, 1992, the NRC issued NUREG-1431 rev 0, the standard technical specifications (STS) for Westinghouse pl ants.
In order to be as consistent as possible with the new STS, we have revised the wording of the proposed Technical Specification. The revised wording does not affect the. conclusions of the significant hazards evaluation that accompanied the request; however, some revisions to the previous submittal are appropriate.
The three enclosures that were attached to letter ELV-03723 should be replaced with the three enclosures attached to this letter.
In accordance with 10 CFR 50.91, the designated state official will be sent a copy of this letter and all enclosures.
Mr. C. K. McCoy states that he is a vice president of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company and that, to the best of his knowledge and belief, the facts set forth in this letter and enclosures are true.
GEORGIA POWER COMPANY
.k 290025 sy:
C K. McCoy Sworntoandsubscribedbeforemethis2 day of ud>us
, 1993.
Wadfut%
Notary' Public wrecausSDufnist,:MkL%lld 93020dD3i 930122 1
i DR ADOCK 0500 4
7
GeorgiaPower A U. S. Nuclear Regulatory Commission ELV-05103 Page 2 CKM/HWM/gmb
Enclosures:
1.
Basis for Proposed Change 2.
10 CFR 20.92 Evaluation 3.
Instructions for Incorporation and Revised Pages c(w): Georaia Power Company
~
Mr. W. B. Shipman Mr. M. Sheibani NORMS U. S. Nuclear Reaulatory Commission Mr. S. D. Ebneter, Regional Administrator Mr. D. S. Hood, licensing Project Manager, NRR Mr. B. R. Bonser, Senior Resident Inspector, Vogtle State of Georaia Mr. J. D. Tanner, Commissioner, Dept. of Natural Resources W
7tMf?$
ENCLOSURE 1 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS ADDITION OF FEEDWATER ISOLATION SYSTEMS BASIS FOR PROPOSED CHANGE Pronosed Chance The proposed change adds new specification 3/4.7.1.6, entitled Main Feedwater Isolation Systems, and associated bases.
The specification requires that the main feedwater isolation and regulating valves and their respective bypass valves be operable or isolated when the reactor is in Modes 1 or 2.
Appropriate action statements and surveillance requirements are included.
The exact text of the new specification is included with enclosure 3.
Basis A main feedwater isolation valve (MFIV) and an associated main feedwaror isolation bypass valve (DFIV) is provided for each of the feedwr.ter lines to the four steam generators.
Each of these lines also contains a main feedwater regulating valve (MFRV) and its associated main feedwater regulating bypass valve (BFRV).
The feedwater line to each steam generator can be isolated by the closure of either a MFIV or MFRV and its associated bypass valve.
These valves provide redundant isolation for each main feedwater line.
All of these valves receive automatic isolation signals from bcth trains of engineered safety features actuation system instrumentation as listed in table 3.3-2 of the Technical Specifications.
The safety-related function of the MFIVs and the MFRVs and their associated bypass valves is to provide isolation for main feedwater flow to the secondary side of the steam generators.
The evaluations of a feedwater malfunction, main steam line break, feedwater line break, small break loss of coolant accident, and steam generator tube rupture take credit for isolating the feedwater lines.
The design basis for the isolation of the feedwater lines was established by the analysis of the main steam line break.
Failure to isolate the feedwater lines would result in additional feedwater to the steam generators that could result in additional cooling and additional mass and energy release.
Since these valves are part of the primary success path for mitigation of a main steam line break, Georgia Power Company has determined that it is appropriate to include them in the Technical Specifications.
The addition of this Technical Specification does not require design changes to the plant or any changes to the safety analyses that are currently in place.
El-1
ENCLOSURE 1 (CONTINUED)
VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS ADDITION OF FEEDWATER ISOLATION SYSTEliS.
BASIS FOR PROPOSED CHANGE The MFIVs and MFRVs (and their associated bypass valves) provide a redundant feedwater isolation capability.
The allowable times for operating with one of the isolation valve combinations inoperable (and open) are consistent with the allowable operating times for operation with inoperable trains of redundant systems.
E The surveillance requirements are met by testing in accordance with Section XI of the ASME Code.
The valve operation time of 5 seconds is consistent with the response time of 7 seconds recorded in table 16.3-2 of the Final Analysis Report (FSAR), since the response time in this table includes an allowance of 2 seconds for signal delay.
El-2
ENCLOSURE 2 VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS ADDITION OF FEEDWATER ISOLATION SYSTEMS 10 CFR 50.92 EVALUATION Pursuant to 10 CFR 50.92, Georgia Power Company (GPC) has evaluated the proposed revision to the Technical Specifications and has determined that operation of the facility in accordance with the proposed amendment would not involve any significant hazards considerations.
Backaround Automatic isolation of the feedwater system has always been a part of the Vogtle Electric Generating Plant (VEGP) design.
The addition of a Technical Specification for the main feedwater isolation system will provide assurance that this system will be maintained operable in a manner consistent with its intended
}
function.
Analysis Automatic isolation of the main feedwater system is provided when required to mitigate the consequences of a feedwater malfunction, main steam line break, feedwater line break, small break loss of coolant accident, or steam generator tube rupture.
The electro-hydraulic fail-closed main feedwater isolation valves (MFIV) and fail-closed air-operated bypass isolation valvo close within 5 seconds on receipt of an engineered safety feature (ESP) actuation signal.
Redundant safety grade feedwater line isolation is provided by the air-operated fail-closed main feedwater regulating (MFRV) and bypass regulating valves, which also close within 5 seconds on receipt of an ESF actuation signal.
Each valve receives a closure signal from both trains of the ESF actuation system.
These closure times are consistent with the values used in the transient and accident analyses described in chapter 15 of the Final Safety Analysis Report (FSAR).
The allowable operating time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for operation with an inoperable isolation system is acceptable because the redundant isolation system is operable.
This time is consistent with the allowable operating time provided in Technical Specification 3.7.1.5 for an inoperable main steam line isolation system.
The proposed Technical Specification allows continued operation with an inoperable isolation valve, provided that the valve is closed within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and is verified to be closed or isolated once per 7 days.
This is acceptable because the safety function of the isolation valve is performed when it is closed.
E2-1
ENCLOSURE 2 (CONTINUED)
VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS ADDITION OF FEEDWATER ISOLATION SYSTEMS 10 CFR 50.92 EVALUATION Since the VEGP is designed to start up using auxiliary feedwater with the MFIVs, MFRVs, and associated bypass valves closed, and since the safety function of the valves is met when closed, the specification is applicable in Modes 1 and 2 except when the MFIV, MFRV or associated bypass valve is closed and deactivated.
The specification allows the isolation system to be considered operable even if a valve in the system is inoperable, provided the valve is closed and deactivated.
It is understood that in Mode 1 a closed main feedwater isolation or main feedwater regulating valve would not allow full power operation because VEGP is not licensed for operation with one loop isolated.
Conclusion Based on the above considerations, GPC has concluded the following concerning 10 CFR 50.92.
- 1. The proposed addition to the Technical Specifications does not involve a significant increase in the probability or consequences of an accident previously evaluated because it adds requirements to maintain the feedwater isolation systems in a state that is consistent with the accidents previously analyzed.
- 2. The proposed addition to the Technical Specifications does not create the possibility of a new or different kind of accident from any accident previously evaluated because it requires the feedwater isolation system to be maintained operable in a manner that is consistent with the current accident analyses and does not introduce any new or different operating requirements for the feedwater isolation systems.
- 3. The proposed addition to the Technical Specifications does not involve a significant reduction in a margin of safety because it will require the feedwater isolation system to perform in accordance with the assumptions used in the safety analyses.
Therefore, operation in accordance with the proposed specification will not affect any of the acceptance limits or analyses used to demonstrate operation within the acceptance limits.
E2-2
s ENCLOSURE 2 (CONTINUED)
VOGTLE ELECTRIC GENERATING PLANT REQUEST TO REVISE TECHNICAL SPECIFICATIONS ADDITION OF FEEDWATER ISQLATION SYSTEMS 10 CFR 50.92 EVALUATION Based upon the preceding information, it has been determined that the proposed Technical Specifications addition does not involve a significant hazards consideration as defined by 10 CFR 50.92(c).
L l.
E2-3
_ _ - _ - _ _ _ _ _ _ - _ _ _ -