ML20137T454
| ML20137T454 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 04/11/1997 |
| From: | ENTERGY OPERATIONS, INC. |
| To: | |
| Shared Package | |
| ML20137T451 | List: |
| References | |
| NUDOCS 9704160098 | |
| Download: ML20137T454 (7) | |
Text
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i CONTAINMENT SYSTEMS i
BASES i
3/4.6.1.7 CONTAINMENT VENTILATION SYSTEM (Continued)
I Leakage integrity tests with a maximum allowable leakage rate for purge supply and exhaust isolation valves will provide early indication of resilient material seal degradation and will allow the opportunity for repair before gross leakage failure develops. The 0.60 La leakage limit shall not be exceeded when the leakage rates determined by the leakage integrity tests of these valves are added to the previously determined total for all valves and i
i penetrations subject to Type B and C tests.
3/4.6.2 DEPRESSURIZATION AND C0OLING SYSTEMS i
I 3/4.6.2.1 and 3/4.6.2.2 CONTAINMENT SPRAY SYSTEM and CONTAINMENT COOLING SYSTEM The OPERABILITY-of the Containment Spray System and the Containment Cooling System ensures that containment depressurization and cooling-capability will be available in the event of a LOCA or MSLB for any double-1 i
ended break of the largest reactor coolant pipe or main steam line. Under post-accident conditions these systems will maintain the containment pressure l
below 44 psig and temperatures below 269.3*F during LOCA conditions or 413.5'F during MSLB conditions. The systems also reduce the containment pressure by a l
factor of 2 from its post-accident peak within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, resulting in lower l
containment leakage rates and lower offsite dose rates.
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The Containment Spray System also provides a mechanism for removing 1
iodine from the containment atmosphere under post-LOCA conditions to maintain doses in accordance with 10 CFR Part 100 limits as described in Section 6.5.2 I
of the FSAR.
l In MODE 4 when shutdown cooling is placed in operation, the Containment j
Spray System is realigned in order to allow isolation of the spray headers.
This is necessary to avoid a single failure of the spray header isolation i.
valve causing Reactor Coolant System depressurization and inadvertent spraying j
of the containment. To allow for this realienment, the Containment Spray l
System may be taken out-of-service when RCS pressure is s 400 psia. At this i
reduced RCS pressure and the reduced temperature associated with entry into MODE 4, the probability and consequences of a LOCA or MSLB are greatly i
reduced. The Containment Cooling System is required OPERABLE in MODE 4 and is j
available to provide depressurization and cooling capability.
I 97o416co9s 970411 ADOCK0500g2' I
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WATERFORD UNIT 3 8 3/4 6-3 Amendment No. 89 4
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4 NPF-38-194 ATTACHMENTB l
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CONTAINMENT SYSTEMS CONTAINMENT COOLING SYSTEM 1
LIMITING CONDITION FOR OPERATION 3.6.2.2 Two independent trains of containment cooling shall be OPERABLE with two fan
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coolers to each train.
APPLICABILITY: MODES 1,2, 3, and 4.
ACTION:
With one train of containment cooling inoperable, restore the inoperable train to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />; restore the inoperable containment cooling train to OPERABLE status within the next 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in COLD SHUTDOWN within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
SURVEILLANCE REQUIREMENTS i
4.6.2.2 Each train of containment cooling shall be demonstrated OPERABLE:
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- a. At least once per 31 days by:
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- 1. Starting each operational fan not already running from the control room and verifying that each operational fan operates for at least 15 minutes.
- 2. Verifying a cooling water flow rate of greater than or equal to 625 gpm to each cooler.
- b. At least once per 18 months by:
- 1. Verifying that each fan starts automatically on an SIAS test signal.
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- 2. Verifying a cooling water flow rate of greater than or equal to 1200 gpm to each cooler.
- 3. Verifying that each cooling water control valve actuates to its full open position on a SIAS test signal.
WATERFORD - UNIT 3 3/4 6-18 AMENDMENT NO. 30
- CONTAINMENT SYSTEMS I
BASES' i
3/4 6.1.7 CONTAINMENT VENTILATION SYSTEM (Continued) d Leakage integrity tests with a maximum allowable leakage rate for purge supply and exhaust isolation valves will provide early indication of resilient material seal degradation and will allow the opportunity for repair before gross leakage failure
- develops. The 0.60 L, leakage limit she.Il not be exceeded when the leakage rates determined by the leakage integrity tests of these valves are added to the previously determined total for all valves and penetrations subject to Type B and C tests.
3/4.6.2 DEPRESSURIZATION AND COOLING SYSTEMS 3/4.6.2.1 ano 3/4.6.2.2 CONTAINMENT SPRAY SYSTEM and CONTAINMENT COOLING SYSTEM The OPERABILITY of the Containment Spray System and the Containment Cooling System ensures that containment depressurization and cooling capability will be available in the event of a LOCA or MSLB for any double-ended break of the largest reactor coolant pipe or main steam line. Under post-accident conditions these systems will maintain the containment pressure below 44 psig and temperatures below 269.3 F during LOCA conditions or 413.5*F during MSLB conditions. The systems also reduce the containment pressure by a factor of 2 from its post-accident peak within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, resulting in lower containment leakage rates and lower offsite dose rates.
The Containment Spray System also provides a mechanism for removing iodine from the containment atmosphere under post-LOCA conditions to maintain doses in accordance with 10 CFR Part 100 limits as described in Section 6.5.2 of the FSAR.
In Mode 4 when shutdown cooling is placed in operation, the Containment Spray System is realigned in order to allow isolation of the spray headers. This it necessary to avoid a single failure of the spray header isoiation valve causing Reactor Coolant System depressurization and inadvertent spraying of the containment. To allow for this realignment, the Containment Spray System may be taken out-of-service when RCS
. pressure is s 400 psia. At this reduced RCS pressure and the reduced teraperature associated with entry into Mode 4, the probability and consequences of a LOCA or MSLB are greatly reduced. The Containment Cooling System is required OPERABLE in Mode
-4 and is available to provide depressurization and cooling capability.
WATERFORD - UNIT 3 B 3/4 5-1 AMENDMENT NO. 34
j CONTAINMENT SYSTEMS i
BASES 3/4.6.2.1 and 3/4.6.2.2 CONTAINMENT SPRAY SYSTEM and CONTAINMENT COOLING SYSTEM (con't) l A train of Containment Cooling consists of two fans (powered from the same safety bus) and their associated coolers (supplied from the same cooling water loop). One j
Containment Cooling train and Containment Spray train has sufficient capacity to
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meet post accident heat removal requirements.
Operating each containment cooling train fan unit for 15 minutes and verifying a cooling water flow rate of 625 gpm ensures that all trains are OPERABLE and that all associated controls are functioning properly. It also ensures that blockage, fan or i
motor failure, or excessive vibration can be detected and corrective action taken.
The 16 month Surveillance Requirement verifies that each containment cooling fan i
j actuates upon receipt of an actual or simulated SlAS actuation signal. The 18 month frequency is based on engineering judgment and has been shown to be I
acceptable through operating experience.
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Verifying a cooling water flow rate of 1200 gpm to each cooling unit provides assurance that the design flow rate assumed in the safety analyses will be
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achieved. The safety analyses assumed a cooling water flow rate of 1100 gpm.
The 1200 gpm requirement accounts for measurement instrument uncertainties and 1
j potential flow degradation. Also considered in selecting the 18 month frequency 1
were the known reliability of the Cooling Water System, the two train redundancy, and the low probability of a significant degradation of flow occurring between i
j surveillances. The flow measurement for the 18 month test shall be done in a configuration equivalent to the accident lineup to ensure that in an sccident situation adequate flow will be provided to the containment fan coolers for them to perform their safety function.
Verifying that each valve actuates to the full open position provides further i
assurance that the valves will travel to their full open position on a Safety injectica r
Actuation Signal.
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j WATERFORD - UNIT 3 B 3/4 5-1a AMENDMENT NO.
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NPF-38-194 ATTACHMENT A i
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CONTAINMENT SYSTEMS CONTAINMENT COOLING SYSTEM LIMITING CONDITION FOR OPERATION j
i 3.6.2.2 Two independent groups of containment cooling fans shall be OPERABLE j
with one fan system to each group.
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APPLICABILITY:
MODES 1, 2, 3, and 4.
1 ACTION:
With one group of the above requiNd containment Cooling fans inoperable, restore i
the inoperable coolins fan to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least l
HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />; rostore the inoperable containment ecoling i
fan to OPERABLE status within the next 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> or be in COLD SHUTDOWN within j
the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
SURVEILLANCE REQUIREMENTS 4
lo 4.6.2.2 Each group of containment cooling fans shall be demonstrated j
OPERABLE:
i a.
At least once per 31 days by:
1.a Starting each fan group not already running from the control room and verifying that each fan group operates for at least 15 minutes.
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2.
Verifying a cooling water flow rate of greater than or equal to j
625 gpa to each cooler.
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At least once per 18 months by:
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Verifying that each fan group starts automatically on an SIAS test signal.
2.
Verifying a. cooling water flow rate of greater than or equal f
to 1325 gpm to each cooler.
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WATERFORD - UNIT 3 3/4 6-18 Amendment No. 39
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