ML20080H689
| ML20080H689 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 02/16/1995 |
| From: | VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | |
| Shared Package | |
| ML20080H687 | List: |
| References | |
| NUDOCS 9502230262 | |
| Download: ML20080H689 (2) | |
Text
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.i b. 9 VYNPS s
3.*7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION Treatment System 2.
a.
The tests and and an alternate sample analysis of electrical power Specification source, consisting 3.7.B.2 shall be of the associated performed initially Emergency Diesel and at least once Generator or Vernon per operating cycle tie, for each not to exceed standby gas 18 months, and treatment circuit following painting, shall be operable fire or chemical at all times when release in any secondary ventilation zone containment communicating with integrity is the system, while required.
the system is operating, that 2.
a.
The results of the could contaminate in-place cold DOP the HEPA filters or and halogenated charcoal adsorbers.
hydrocarbon tests at design flows on b.
Cold DOP testing HEPA and charcoal shall be performed filter banks shall after each complete show 199% DOP or partial removal and 199%
replacement of the halogenated HEPA filter bank.
hydrocarbon removal.
c.
Halogenated hydrocarbon testing b.
The results of shall be performed laboratory carbon after each completo sample analysis or partial shall show 195%
replacement of the radioactive methyl charcoal filter iodide removal.
bank.
(130*C, 95% RH).
Laboratory analysis In addition, the results shall be sample analysis of verified acceptable Specification within 31 days 3.7.B.2.b and the following sample halogenated removal or the hydrocarbon test applicable train of shall be performed the Standby Gas after every Treatment System 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of normal l shall be considered system operation.
in-operable and the requirements of d.
Each circuit shall Specification be operated with 3.7.B.3 shall the heaters on at apply.
least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> every month, c.
System fans shall be shown to operate e.
An ultrasonic leak within 10% of test shall be design flow, performed on the gaskets sealing the housing panels downstream of the HEPA filters and 9502230262 950216 adsorbers at least PDR ADOCK 05000271 P
PDR Amendment No. M, 49 153
ja e
VYNPS BASES:
3.7 (Cont'd) l The Standby Gas Treatment System (SGTS) is designed to filter and exhaust the Reactor Building atmosphere to the stack during secondary containment isolation conditions, with a minimum release of radioactive materials from the Reactor Building to the environs. To insure that the standby gas treatment system will be effective in removing radioactive contaminates fram the Reactor Building air, the system is tested periodically to meet the intent of ANSI N510-1975.
Both standby gas treatment fans are designed to automatically start upon containment isolation and to maintain the Reactor Building pressure to approximately a negative 0.15 inch water gauge pressure; all leakage should be in-leakage. Should the fan fail to start, the redundant alternate fan and filter system is designed to start automatically. Each of the two fans has 100% capacity. This substantiates the availability of the operable circuit and results in no added risk thus, reactor operation or refueling operation can continue.
If neither circuit is operable, the plant is brought to a condition where the system is not required.
j When the reactor is in cold shutdown or refueling the drywell may be open and the Reactor Building becomes the only containment system.
During cold shutdown the probability and consequences of a DBA LOCA are substantially reduced due to the pressure and temperature i
limitations in this mode. However, for other situations under which significant radioactive release can be postulated, such as during operations with a potential for draining the reactor vessel, during core alterations, or during movement of irradiated fuel in the secondary containment, operability of standby gas treatment is i
required. An alternate electrical power source for the purposes of Specification 3.7.B.1.b shall consist of either an Emergency Diesel Generator (EDG) or the Vernon Hydro tie line. Maintaining availability of the Vernon Hydro tie line as an alternative to one of the EDGs in this condition provides assurance that standby gas treatment can, if required, be operated without placing undue constraints on EDG maintenance availability.
Inoperability of both circuits of the SGTS or both EDGs during refueling operations requires suspension of activities that represent a potential for releasing radioactivs material to the secondary containment, thus placing the plant in a conditior. that minimizes risk.
Use of the SGTS, without the fan and the 9 kW heater in operation, as a vent path during torus venting does not impact subsequent adsorber capability because of the very low flows and because humidity control is maintained by the standby 1 kW heaters, therefore operation in j
this manner does not accrue as operating time.
D.
Prima *v Containment Isolation Valves Double isolation valves are pro.fded on lines that penetrate the primary containment and communicate directly with the reactor vessel and on lines that penetrate the primary containment and communicate with the primary containment free space. Closure of one of the valves in each line would be sufficient to naintain the integrity of the pressure suppression system. Automatic initiation is required to minimize the potential leakage paths from the containment in the event of a loss-of-coolant accident.
/
4.7 STAT 70N CONTAINMENT S'ISTEMS A.
Primary Containment Sv9 tam The water in the suppression chamber is used only for cooling in the enat of an accident, i.e.,
it is not used for normal operation; therefore, a weekly check of the temperature and volume is adequate to assure that adequate heat removal capability is present.
Amendment No. H, 49 166