ML17289A405
| ML17289A405 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 03/18/1992 |
| From: | WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | |
| Shared Package | |
| ML17289A404 | List: |
| References | |
| NUDOCS 9203250294 | |
| Download: ML17289A405 (7) | |
Text
The following'ages will be affected by this Technical Specification amendment.
REMOVE 3/4 6-44 B 3/4 6-5 INSERT 3/4 6-44 B 3/4 6-5 B 3/4 6-6 9203250294 920318 PDR ADOCK 05000397 P
~1
CONTAINMENT SYSTEMS 3/4.6.6 PRIMARY CONTAINMENT ATMOSPHERE CONTROL DRYWELL AND SUPPRESSION CHAMBER HYDROGEN RECOMBINER SYSTEMS LIMITING CONDITION FOR OPERATION 3.6.,6. 1 Two independent drywell and suppression chamber hydr'ogen recombiner systems shall be OPERABLE.
APPLICABILITY:
OPERATIONAL CONDITIONS 1 and 2.
SURVEILLANCE RE UIREMENTS 4.6.6. 1 Each drywell and suppression chamber hydrogen recombiner system shall be demonstrated OPERABLE:
b.
At least once per 6 months by verifying during a recombiner system warmup test that the minimum recombiner heater outlet temperature increases to greater than or equal to 500QF within 90 minutes.
At least once per 18 months by:
1.
Performing a
CHANNEL CALIBRATION of all recombiner operating instrumentation and control circuits.
2.
Verifying the integrity of all heater electrical circuits by performing a resistance to ground test within 30 minutes following the above required functional test.
The resistance to ground for any heater phase shall be greater than or equal to 10,000 ohms.
c,g
/t 0+
t %
3.
Verifying during a recombiner system functional est that, upon introduction of by volume hydrogen cant~~
me-ox3tg ut-es.
ACTION:
With one drywall and suppression chamber hydrogen recombiner system s noperable, restore the inoperable system 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 />.
Q)
Dy O
5U Ql ~
5-st5 Vl 5
Q5 ~
E E OJ st5 CJ5-it5 M O
+J'J Q5 rC5 ti-QI tl-QJ CI 5
CJ O. N O
QI JD L3' MO V) O st5 M C5 lt5 Ql O OX Q)
CJ O
Q O
~r QlE O
VI VI CI
~J O
O
~r st55-CJO QO 4.
Verifying through a visual examination that there is no evidence of abnormal conditions within the recombiner enclosure; i.e.,
loose wiring or structural connections, deposits of foreign materials, etc.
c.
By measuring the system leakage rate:
2.
As a part of the overall integrated leakage rate test required by Specification 3.6. 1.2, or By measuring the leakage rate of the system outside of the containment isolation valves at P
, 34.7 psig, on the schedule required by Specifiation 4.6. 1.2, and including the measured leakage as a part of the leakage determined in accordance with Specification 4.6. 1.2.
WASHINGTON NUCLEAR - UNIT 2 3/4 6-44 Amendment No.
26
II I
CONTASNMENV SYSTEMS BASES 3/4.6.4 VACUUM RELIEF Vacuum relief breakers are provided to equalfle the pressure between the suppression chamber and drywall and between the reactor bufldfng and suppres-sion chamber.
This system will maintain the structural integrity of the primary containment under conditions of large differential pressures.
The vacuum breakers between the suppression chamber and the drywell must not be inoperable in the open posftion since this would allow bypassing of the suppression pool fn case of an accfdent.
There are nine pairs of valves to provide redundancy and capacity so that operatfon may continue indefinitely with no more than two pairs of vacuum breakers inoperable in the closed pos ltlon.
3/4.6s5 SECONDARY CONTAINMENT Secondary containment is designed to mfnfmfze any ground level release of radioactive material which may result from an accident.
The reactor building and associated structures provide secondary containment during normal opera-tion when the drywell fs sealed and in service.
At other times the drywell may be open and, when required, secondary containment integrity fs specified.
Establfshfng and maintaining a vacuum fn the reactor building with the standby gas treatment system ance per 18 months, along with the surveillance of the doors,
- hatches, dampers, and valves, fs adequate to ensure that there are no violations of the fntegrfty of the secondary containment.
The OPERABILITY of the standby gas treatment systems ensures that suf" ficient iodine removal capability will be available in the event of a LOCA.
The reduction in containment iodine inventory reduces the resulting SITE BOUNDARY radiation dases associated with containment leakage.
The operation of thfs system and resultant iodine removal capacity are consistent with the assumptions used in the LOCA analyses.
Continuous operation of the system with the heaters OPERABLE for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> during each 31 day period is sufficient to r educe the buildup of mofsture on the adsorbers and HEPA filters.
~ ~ pXy'g 3/4.6.6 PRIMARY CONTAINMENT ATMOSPHERE CONTROL AÃ g~qp fAtXV~
The OPERASILITY of the systems required for the detectio and contr/1 ot oayg<A /hydrogen gas ensures that these systems uf 1 1 he aval lahle to aintain the, yg IM 5 t" u
'th'" tl p"I Y
I f b
WaI+ during post-lOCA conditions.
Efther drywell and suppression chamber Qpy9eo/hydrogen recombiner system fs capable of controlling the expected 4ydmgen <<yg~
generation associated with radiolytfc decomposition of water The y
9ejly hydrogen control syst is consistent with the recommendations of Regulatory Guide 1.7, "Control of Combustfble Gas Concentrations fn Containment Following a LOCA," September 1S76.
$ JQ gases c.
4!ASHINGTON NUCLEAR - UNIT 2
'8 3/4 6-5 Amendment No.i00
Addition for 3/4.6.6 Basis
- (will become page B 3/4 6-6)
Following an accident the inerted primary containment oxygen level is controlled to not exceed 4.8%
by volume with the catalytic recombiner system.
By FSAR Figure 6.2-26 the containment will reach 4.8% oxygen between 10 and 60 hours6.944444e-4 days <br />0.0167 hours <br />9.920635e-5 weeks <br />2.283e-5 months <br /> after the accident if the recombiner system is not operating.
To provide assurance that recombiners are capable of achieving the required oxygen removal, the feed and effluent streams will be sampled for the surveillance to establish that the effluent hydrogen concentration is less than 25 ppm by volume for a feed of at least 1% hydrogen by volume.
This will confirm a minimum efficiency of 99.75% for the expected range of post-accident conditions.
This efficiency will be adequate to maintain the.post-accident oxygen level below 4.8% by volume.
The CAC system employs a platinum on alumina catalyst to recombine the oxygen and hydrogen flow from the containment.
During accident conditions, the gas mixture is preheated to appr'oximately 450 to 550'F prior to entering the catalyst.
This preheat increases the effectiveness of the hydrogen/oxygen recombination because it limits the potential for bed poisoning.
For testing purposes, the gas mixture will be preheated prior to entering the catalyst to ensure the required activation energy of the recombination is reached.
In the test configuration, the blower is used as the only source of gas stream heating and the catalyst preheaters are not energized.
The blowers are capable of heating the gas stream by compression.
Temperatures at the blower exit are limited for test purposes to approximately 300'F due to the blower gas exit temperature trip setpoint.
~'w
'%J
~p '