ML20151J326
| ML20151J326 | |
| Person / Time | |
|---|---|
| Site: | 05000054 |
| Issue date: | 07/21/1988 |
| From: | CINTICHEM, INC. |
| To: | |
| Shared Package | |
| ML20151J324 | List: |
| References | |
| NUDOCS 8808020225 | |
| Download: ML20151J326 (4) | |
Text
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ENG.06URE 3-1 R-81 License - Technical Specifications PRESENT TECHNICAL SPECIFICATION Section 3.3.4 - Measuring mannels The minimum number and type of measuring channels operabl e and providing Inf ormation to the control roca operator required for reactor operation are give In Table 3.1.
Table 3.1 Minimum number and operating mode of measuring channels mannel Minimum No. Operable Operatina Mode Reautred Power Level (normal) 2 All l
- Power Level (Intermediate) 1 All l Period Channel 1 All l Count Rate la Startup j Cool ant FI ou 1 Forced Cooling
- Core Delta T 1 Forced Cooling Rod Position 1/ rod All Pool Temperature 1 All
]
I Pool Level 1 All
' Operable below 50 W
)
1 Basis: The normal power level Instruments (level saf eties) provide redundant
] Information on reactor power in the range 255 - 150% of the normal operating j pow er l ev el of 5 m.
l The Intermediate power instrument (Log N) provides usable reactor power Information in the logarithmic range 10-45 to 300% of the normal power of SMW.
l PROPOSED CHANGE l The Intermediate pow er Instrument (Log N) provides usable reactor power i
inf ormation with a minimum locarithmic rence of 10-45 to 2005 of the normal l power of 5 W. 5
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i DNLOSURE 3-2 Section 5.2.2 Power Level (Intermediate) Qiannel PRESENT TE04NICAL SPEClFICATION i
i for this f unction, a single channel i s prov ided, covering reliably the range 10-35 to 3005 (of 5 *) with a logarithmic output Indication on both a panel l meter and a chart recorder. To cover the range under all core cenditions, a
, gamme-compensated boron-lon chamber is used to suppiv a logarithmic mplifier.
l The chamber can be changed in position, over a l talted range, so as to allow 1 the channel reading to be standardized against reactor thermal power. Rate of 1 change of power Inf ormation is also derived, in the f orm of a period, that can e produce a f ast scram (and backup slow serem) In the same way as in Section
- 5.2.1. Control and inhibit actions (viz., bypassing of count rate channel j functions, bypassing of flow and flapper scrans) are also deriv 9d from this channel, i To negate the of feet of over compensation in the ton chanter, which can occur
- under certain conditions, even in an initially under compensated chamber, provlslon i s made to su an adjustable small current to the channel
- ampilfler (up to 1.5 x 10-glymps) so as to f acilitate startup.
I l
! PROPOSED 04ANGE For th i s' f unction, a single channel i s prcv ided, covering reliably the range j 10-35toQ0.0)(of5W) with a logarithmic output Indiretton on both a panel 1 meter and a chart r9 corder. To cover the range under all core conditions, a j game-ccepensated boron-lon chamber is used to supply a logarithmic ampilfler.
4 The chamber can be changed in position, over a limited range, so as to allov the channel reading to be standardized egelnst reactor thermal pomer. Rate of I change of power information is also derived, in the f orm of a period, that can
! produce a f ast scram (and backup slow scr am) in the swo way as in Section
' 5.2.1. Control and inhibit actions (viz., bypassing of count rate channel functions, bypassing of fica and flapper scrams) are also derived frca this i ch annel, s
To negate the of feet of over compensation in the ton chamber, which can occur under certair. condi tions, even in an initially eder ccupensated ch asber, l provision mov be made to current to the channel supl i f ier up to 1.5 x 10-1gupply an adjustable smallamps) so as to fiellita+e startup.
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. ENCLOSURE 4-1 l
Basis: The power level scram provides redundant automatic protective action Q~ ' to prevent exceeding the safety limit on reactor power.
l The period scram, assisted by the intermediate level per iod reverse and rod inhibit, limits the rate of increase in reactor power to values that are ;
controllable without reaching excessive power levels or temperature. These l functions are not limiting safety system settings. ,
The two inhibits on'the count rate channel prevent inadvertent critica11ty during cold startup that could arise from lack of neutron information or from too rapid reactivity insertion by control rods.
The scram pool on level provides an adequate head of water above the core and ,
guards against loss of coolant and loss of building containment. l i
The coolant flow and flapper valve scrams ensure adequate coolant flow to !
prevent boiling in the core.
1 1 The scrams on bridge lock and guide tubes prevent unplanned reactivity changes i
that could occur through corg and control element movements, respectively,
, The keyswitch scram prevents unauthorized operation of the reactor.
Bypass is permitted on those parameters that can be monitored by alternate !
means if the initiating circuit malfunctions. I i
< 3.4 Radiation Monitoring Systems j Applicability: This specification applits to the radiation monitoring systems .
i required for safe operation of the reactor, operating personnel protection, and i protection of the public.
- a Cbjective: The objective is to ensure that operation of the reactor is within '
! the goal of ALARA and to detect the release of fission products within Union L Carbide Subsidiary (UCS) set limits. [
i specifications: The specifications for the minimum acceptable monitoring instrumentation required for reactor operation are given in Table 3.3. l I
l Basis: These setpoints produce less personnel exposure than indicated in Td CTR Part 20, and permit early identification of fuel cladding or process ,
- system failure. -
3.5 Engineered Safety Features Apolicability: These specifications apply to required equipment for the con- !
l Tinement of activity through controlled -elease of reactor ouilding air to the !
j atmosphere.
I i j Objective: The objective is to ensure personnel are notified about high radi- l l
ation incidents and to initiate engineered safeguards systems for safe shutdown i
)
of the reactor and mitigation of release of radioactivity to the environment. [
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. , . ENCLOSURE 4-2 Table 3.3 Radiation monitoring systems Sc No. Max alarm Type operable setpoint Function Excursion monitor 1 5 R/hr Detect high radiation:
Alarm and isolate at >5 R/hr Exhaust duct monitor
- 1 Detect particulate, gas, and
("stack monitor") iodine activities; alarm in control room Building continuous 1 **
Detect particulate activity air monitor (CAM) in reactor building; alarm in control room Fixed area monitor 3 50 mr/hr Detect radiation (y) in key '
locations; alarm in control room Evacuation switch 1 --
Alarn and initiate evacuation sequence (manual)
Note: For maintenance or repiir, required radiation monitors (except for
,n excursion monitor) may be replaced by portable or substitute q) instruments for periods up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> provided the function will still R be accomplished. Interrt.otion for brief periods to permit checking or calibration is permissible.
- The alarm setpoint for the stack gas monitor shall not be set above a value that would result in an exposure greater than 2 mrem per hour assu,ing a dilution factor of 2000 and the isitope mixture determined by the annual environ.: ental report or nost recent analysis. The alarm setpoint for the stack I-131 and stack particulate monitor shall not be set above a value corresponding to that listed in~Apperdix 0. Table II, Colum.n I of 10 CFR Part 20, assuming a dilution factor of 2000 and averaging over one week.
"25', of the maximum permissible concentt ation at restrim ! areas according to Appendix S of 10 CFR Part 20.
5:ecificaticos: The specifications are as f ollows:
3.5.1 Excursion Monitor Specific!tien- See Section xkiix 3.4 f Basis: This ?;nitor ienses excessive rcdi3 tion at the reactor D'iMe arJ n. t o '
natically in'tiates tne "ev 3cuation sequence," which censists of a ilist'n;tt' e
,3 ala n , closure of da ;er valves in the building ventilation system anJ ralc up G ~
tank vent, and starting of the erergency eth3ust fan (see Section 5.5.2).
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