ML18036A546
| ML18036A546 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 03/12/1992 |
| From: | Zeringue O TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TVA-BFN-TS-251, NUDOCS 9203190150 | |
| Download: ML18036A546 (14) | |
Text
ACCELERATED DISTRIBUTION DEMONSTFMTION SYSTEM Os" REGULATG.
INFORMATION DISTRIBUTION STEM (RIDS)
ACCESSION NBR:9203190150 DOC.DATE: 92/03/12 NOTARIZED:
NO DOCKET FACIL:50-260 Browns Ferry Nuclear Power Station, Unit 2, Tennessee 05000260 AUTH.NAME AUTHOR AFFILIATION ZERINGUE,O.J.
Tennessee Valley Authority RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Provides addi info on primary containment isolation valve configurations to follow-up 920116 telcon w/NRC.Info supplemental to info provided in 910627 ltr re TS 251 on subj valve App J program.
DISTRIBUTION CODE:
A017D COPIES RECEIVED:LTR 2 ENCL SIZE:
TITLE: OR Submittal:
Append J Containment Leak&ate Testing NOTES:
RECIPIENT ID CODE/NAME SANDERS,M.
ROSS,T.
INTERNAL: ACRS OC/LFNB R
~FTIl R
DSTR/SA'T EXTERNAL: NRC PDR COPIES LTTR ENCL 1
0 2
2 6
6 1
0 1
1 1
1 1
1 RECIPIENT ID CODE/NAME HEBDON,F NRR/DST/SPLB 8D OGC/HDS3 RES/DE/SEB RES/DSR/RPSB NSIC COPIES LTTR ENCL 1
1 NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAMEFROM DISTRIBUTION LINIS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 19 ENCL 17
if'
Tennessee Valley Authority, Post Office Sox 2000, Decatur,'Alabama 35609 O. J. 'Ike'eringue Vice President. Browns Ferry Operations TVA-BFN-TS-251 10 CFR 50.90 t-gg i2 t997 U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk Washington, D.C.
20555 Gentlemen:
In the Matter of Tennessee Valley Authority Docket No. 50-260 BROWNS FERRY NUCLEAR PLANT (BFN) TVA BFN TECHNICAL SPECIFICATION (TS)
NO. 251 PRIMARY CONTAINMENT ISOLATION VALVES AND BFN APPENDIX J PROGRAM
References:
1.
TVA letter to NRC dated June 27,
- 1991, TS 251 Withdrawal of TS for Units 1 and 3 and Comments on Safety Evaluation Report (SER) for Unit 2 Primary Containment Isolation Valves and BFN Appendix J Program 2.
NRC letter to TVA dated March 22,
- 1991, Issuance of Amendment and Compliance Review of 10 CFR 50 Appendix J, and TMI Item II.E.4.2.1-4 (TAC Nos.
0081 and 74609)(TS-251) 3.
TVA letter to NRC dated September 17,
- 1990,
Response
to NRC Recommendations Regarding Primary Containment Isolation (TAC Nos.
- R00080, R00081, and R00082)
By Reference 1,
TVA submitted comments on the SER issued by Reference 2.
To resolve the comments, TVA and NRC representatives held a teleconference on January 16, 1992.
This letter provides additional information on BFN primary containment isolation valve configurations to follow-up the information discussed in the teleconference.
This information is supplemental to the information provided in Reference 1.
TVA's responses to items that were discussed in the teleconference are enclosed.
9203190i50 9203l2
.PDR '>ADQCK 05000260 P
igy ii
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, U.S. Nuclear Regulatory Commission Fi"'~R X 2 H92 There are no commitments contained in this letter.
Please refer any questions concerning this submittal to R. R. Baron, Manager of Site Licensing, at (205) 729-7566.
Sincerely,
- 0. J. Zeringue Enclosure cc:
See page 3
ii
, U.S. Nuclear Regulatory Commission NR l2 )ssz Enclosure cc '(Enclosure):
American Nuclear Insurers ATTN:
Librarian The Exchange, Suite 245 270 Farmington Avenue Farmington, Connecticut 06032 Mr. Johnny Black, Chairman Limestone County Commission 310 Washington Street
- Athens, Alabama 35611 Dr. C. E. Fox State Health Officer State Department of Public Health State Office Building Montgomery, Alabama 36194 Mr. J. E. Jones General Electric Company 735 Broad Street
,Suite 1108 James Building Chattanooga, Tennessee 37402 NRC Resident Inspector Browns Ferry Nuclear Plant Route 12, Box 637
- Athens, Alabama 35611 Mr. Thierry M. Ross, Project Manager U.S'. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 Mr. B. A. Wilson, Project Chief U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
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t ENCLOSURE ADDITIONALINFORMATIONCONCERNING BFN CONTAINMENTISOLATIONVALVES 1 ~
Concerni.ng, item (1) in the enclosure to TVA's June 27, 1991 letter, TVA stated that it was believed that the inboard and outboard'alves were powered from separate and diverse power supplies and agreed to confirm this.
~Res onse Main Steam Drain isolation valves 2-FCV-1-55 and 2-FCV-1-56 are powered by 480 Volt RMOV boards
'2A and 250 V DC RMOV board 2B respectively, which are diverse power supplies.
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Concerning item (2) in the enclosure to TVA's June 27, 1991 lette'r, TVA stated that it was believed that during normal operation, the inboard valve is not opened and is in TVA's locked valve program.
TVA agreed to confirm this information.
~Res onse The inboard manual globe valve (2-2-3353) is included in TVA's locked valve program; 3.
Concerning item (3) in the enclosure to TVA's June 27, 1991 letter, NRC stated that the feedwater heater outlet valves should be listed in procedures to aid operators for long term isolation purposes.
TVA agreed to report the procedural references to these valves.
~Res ense TVA evaluated the ieedwater heater outlet valves (2
FCV 3 -75,--
-76,.and -77) as potential isolation sources in the secondary containment control section of 2-EOI-3.
As stated in TVA's June 27, 1991 letter, these valves are physically located in the turbine building and therefore would not represent
.an isolation point for high energy primary systems into secondary containment.
Based on.this analysis, the valves were not identified in 2-EOI-3.
In addition, Operating Instruction 2-OI-3 REACTOR FEEDWATER SYSTEM instructs operators to close the feedwater heater outlet valves when shutting down the RFW System.
Operators would operate the feedwater heater outlet valves, as necessary, to secure the system in post-accident situations and these instructions provide adequate operator guidance.
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t ENCLOSURE ADDITIONALINFORMATIONCONCERNING BFN CONTAINMENTISOLATIONVALVES Concerni.ng item (5) in the enclosure to TVA's June 27, 1991 letter--
recirculation system, NRC asked if there were other valves in these lines outside primary containment.
TVA agreed to provide the necessary clarifying information.
~Res onse The 3/4 inch lines at penetrations 37C and 38C provide recirculation pump seal injection water to reactor recirculation pumps A
and B respectively.
Major system design features are as follows a common seal injection line is fed by the CRD hydraulic pumps, equipped with discharge check valves and inlet and outlet isolation valves.
The common seal injection line splits into two lines.
Each has a manual seal supply shutoff valve, manual flow control valve and manual isolation valve outside containment.
At the containment penetration for each line are the containment isolation check valves -- one inside and one outside primary containment.
Another manual isolation valve is located inside primary containment before the respective recirculation pump.
For long-term accident situations, recirculation pumps would not be operating.
To prevent damage to the recirculation pump seals, operating procedure 2-OI-68 'REACTOR RECIRCULATION SYSTEM contains a caution to never isolate a recirculation pump with the CRD seal supply isolation valve open.
Upon each recirculation pump shutdown, the procedure includes steps to locally close seal supply shutoff valve 2-68-568 (559) to the recirculation pump(s),
and to monitor seal pressure to ensure the valve is not leaking.
Thus, existing procedures instruct operators to close these valves which provide the desired additional, positive means of isolation for long-term isolation purposes.
The system design provides additional barriers against leakage out of primary containment into secondary containment.
If seal supply shutoff valves 2-68-568 and 2-68-559 are inaccessible, additional failures must occur (beyond the postulated accident and failure of the check valves to seal against low differential pressure) before containment integrity is jeopardized.
The following additional barriers are available for scenarios where the CRD pumps are and are not running:
The CRD system pumps are expected to be kept running in post-accident situations to supply charging water to the CRD units.
The pressure from the supply water would prevent backleakage through the containment isolation double check valves.
If a CRD pump is not operating, by normal procedure the pumps would be isolated from the seal injection lines via the pump isolation valves.
Also, each pump has a discharge check valve.
These features provide additional barriers even if water leaks past the containment isolation double check valves.
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t ENCLOSURE t ADDITIONALINFORMATIONCONCERNING
'BFN CONTAINMENTISOLATIONVALVES Concerning item (6) in the enclosure to TVA's June 27, 1991 letter, NRC asked if there were other valves in these lines outside primary containment.
TVA agreed to review drawings for the valves and ascertain the function of these valves.
~Res onse For the RWGU in2ection line, 2
F-CV 6-9 1-2 is located outside primary containment and controls water flow from RWCU into the feedwater lines.
This valve is listed in 2-EOI-3 as a potential isolation source for RWCU.
For the RWCU supply line, inboard and outboard motor operated isolation valves 2-FCV-69-1 and 2-FCV-69-2 isolate automatically on a group 3 signal.
These valves are also listed as potential isolation sources in 2-EOI-3 and are acceptable as stated on page 10 of the SER.
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