ML17290A827
| ML17290A827 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 12/06/1993 |
| From: | WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | |
| Shared Package | |
| ML17290A826 | List: |
| References | |
| NUDOCS 9312160182 | |
| Download: ML17290A827 (10) | |
Text
CONTAINMENT SYSTEMS CONTROLLED COPY MSIV LEAKAGE CONTROL SYSTEM LIMITING CONDITION FOR OPERATION 3.6. 1.4 Two p( @de~!
HSIV leakage control system (LCS) subsystems shall be OPERABLE.
APPLICABILITY:
OPERATIONAL CONDITIONS 1, 2, and 3.
ACTION:
With one MSIV leakage control system subsystem inoperable, restore the inoperable subsystem to OPERABLE status within 30 days, or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
J,
(~snab (r <<oZello~'up~gc)
SURVEILLANCE RE UIREMENTS 4.6. 1.4 Each MSIV leakage control system subsystem shall be demonstrated OPERABLE:
a.
At least once per 31 days by:
1.
Starting the blower(s) from the control room and operating the blower(s) for at least 15 minutes.
(us. b 4r.
Pa(o~,
Z T-m) ug
$ e-t- <>
At least once er 18 months byj o CAP 4401 g g$ emw r an o-,,
nc n
-hi-n d
v
->-f-
. au mat.'vale
- b.
we -su t-io
'y verifying the flow, pressure and temperature instrumentation to be OPERABLE by performance of a:
1.
CHANNEL FUNCTION TEST at least once per 31 days, and 2.
CHANNEL CALIBRATION at least once per 18 months.
WASHINGTON NUCLEAR - UNIT 2 9312160182 931206 PDR ADOCK 05000397 F
PDR 3/4 6"7 Amendment No. 1OO
4
~
~
0
Insert to Page 3/4 6-7, MSIV Leakage Control System
~AT~IN b.
With two MSIV leakage control system subsystems inoperable, restore one MSIV leakage control system to OPERABLE status within 7 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
SURVEILLANCERE UIREMENT 4.6.1.4....
ao 2.
Verifying electrical continuity of each inboard MSIV leakage control system subsystem heater element circuitry.
CONTAINMENT SYSTEMS BASES 0
CONTRGLLED COPY sc<4.
MSIV LEAKAGE CONTROL SYSTEM (Continued Des>gn specifications require t system to accommodate a leak rate of five times the Technical Specificat on leakage allowed for the MSIVs while maintaining a negative pressure nstream of the MSIVs.
The al]owed leakage value per each valve is 11.5 scfm or a total of 230 scfh (3.8 scfm).
Mhen corrected for worst case press e, temperature and humidity expected to be seen during surveillance testing conditions, the flow would never exceed an indi-'Red@~
~~
cated value uncorrected readin from local flow instrumentation) of 5 cfm.
The 30 acc ance terio rovide gnif t ma n
is+efl bas'equ'ent rovi s
a be mark f eval sn n
term bi@ er rform e.
he Technical Specification lsmst for pressure of -17" Hq0 M.C.
was also es ablished based on a benchmark of the installed system performance capability.
This -17" H>0 M.C. provides assurance that the negative pressure criterion can be met.
3/4.6.1.5 PRIMARY CONTAINMENT STRUCTURAL INTEGRITY This ltmitatson ensures that the structura 1ntegrity of the containment steel vessel will be maintained comparable to the original design standards for the life of the unit.
Structural integrity is required to ensure that the containment will withstand the maximum pressure of 34.7 psig in the event of a LOCA.
A visual inspection in conjunction with Type A leakage tests is sufficient to demonstrate this capability.
3/4.6. 1.6 DRYWELL AND SUPPRESSION CHAMBER INTERNAL PRESSURE The l>mstatsons on drywell and suppression chamber internal pressure ensure that the containment peak pressure of 34.7 psig does not exceed the design pressure of 45 psig during LOCA conditions or that the external pressure differential does not exceed the design maximum external pressure differential of 2 psid.
The limit of 1.75 psig for initial positive contain-ment pressure will limit the total pressure to 34.7 psig which is less than the design pressure and is consistent with the safety analysis.
3/4.6.1.7 DRYWELL AVERAGE AIR TEMPERATURE The limitation on drywell average air temperature ensures that the containment peak air temperature does not exceed the design temperature of 340'F during LOCA conditions and is consistent with the safety analysis.
3/4.6.1:8 DRYMELL AND SUPPRESSION CHAMBER PURGE SYSTEM The 24-inch and 30-inch drywell and suppress>on chamber purge supply and exhaust isolation valves are required to be sealed closed during plant operation since these valves have not been -',demonstrated capable of closing during a LOCA or steam line break accident.:
Maintaining these valves sealed closed during plant operations ensures that'xcessive quantities of radio-active materials will not be released via the purge system.
To provide assurance that the 24-inch and 30-inch valves cannot be inadvertently opened, they are sealed closed in accordance with Standard Review Plan 6.2.4, which includes mechanical devices to seal or lock', the valve closed or prevent power from being supplied to the valve operator.
(a)
Letter, G02-75-238, dated August 18, 1975, NO Strand (SS) to OD Parr (NRC), "Response to Request for Information Main Steam Isolation Valve Leakage Control System" WASHINGTON NUCLEAR " UNIT 2
~
B '3/4 6-,2 Amendment No.
iOO
I P
Insert A to Bases 3/4.6.1.4, page 3/4 6-2 The 30 + 6 cfm acceptance criterion provides adequate margin to the value necessary to accommodate this leakage rate while maintaining adequate system vacuum.
Also, the 30 + 6 cfm acceptance criterion, given worst case flow, temperature and humidity values, provides the necessary blower fan cooling to assure proper operation of the MSIVLCS and ensure that the process stream delivered by the MSIVLCS is within the capabilities of the SGT.
Further, it provides a benchmark for evaluating long term blower performanc'e.
4
Insert B to Bases 3/4.6.1.4, page B 3/4 6-2 The system functional test, Surveillance 4.6.1.4.b of each subsystem is performed to ensure that the MSIVLCS will operate through its operating sequence.
This includes verifying that the automatic positioning of the valves and the operation ofeach interlock and timer are correct, that the blowers start and develop the required flowrate and the necessary vacuum (at least -17" H~O at the blower suction, with 30 + 6 cfm dilution flow), and that the upstream heaters control temperature adequately.
, ~
P
'W A
STATE OF WASHINGTON)
)
COUNTY OF BENTON
)
Subject:
Request for Amend to TS 3/4.6.1.4 MSIV ka e on rol tern I. J. V. PARRISH, being duly sworn, subscribe to and say that I am the Assistant Managing
- Director, Operations for the WASHINGTON PUBLIC POWER SUPPLY SYSTEM, the applicant herein; that I have the full authority to execute this oath; that I have reviewed the foregoing; and that to the best of my knowledge, information, and belief the statements made in it are true.
DATE
, 1993 J.. Parrish, Assistant Managing Director perations On this date personally appeared before me J. V. PARRISH, to me known to be the individual who executed the foregoing instrument, and acknowledged that he signed the same as his free act and deed for the uses and purposes herein mentioned.
GIVEN under my hand and seal this~day of D
1993.
Notary Public in and for the STATE OF WASHINGTON Residing at My Commission Expires