ML17228B189
ML17228B189 | |
Person / Time | |
---|---|
Site: | Saint Lucie ![]() |
Issue date: | 06/21/1995 |
From: | FLORIDA POWER & LIGHT CO. |
To: | |
Shared Package | |
ML17228B188 | List: |
References | |
NUDOCS 9506280119 | |
Download: ML17228B189 (29) | |
Text
3/4.5 EMERGENCY CORE COOLING SYSTEMS ECCS SAFETY INJECTION TANKS 5 tT)
LIMITING CONDITION FOR OPERATION 3.5.1 Each reactor coolant system safety injection tank shall be OPERABLE with:
- a. The isolation valve open,
- b. Between 10'70 and 1170 cubic feet of borated water,
- d. A nitrogen cover-pressure of between 200 and 250 psig.
APPLICABILITY: MODES 1, 2 and 3.*
ACTION:
of a close alve, res 'erable tank to OPERABLE stat oor~M HOT SHUTDOWN within ours sa e y ingection an snopera e ue o valve being c , er immediately-ope e isolation valve or be in HOT ST DSY~4tlriw on be in HOT SHUTDOWN
'M~ e next 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
SURVEILLANCE RE UIREMENTS 4.5.1 Each safety injection tank shall be demonstrated OPERABLE:
- a. At leas't once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by: horeg~g uoXev voIume.
- l. Verif in the and nitrogen cover-pressure in
~k the tanks and, ax~ ~'Ahtn Whee hiui+s
- 2. Verifying that each safety injection tank isolation valve is open.
With pressurizer pressure > 1750 psia.
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St. Lucie Unit 1 and Unit 2 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension IN ERT-A a~ With one SIT inoperable due to boron concentration not within limits, or due to an inability to verify the required water volume or nitrogen cover-pressure, restore the inoperable SIT to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />; otherwise, 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 /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
INSERT - B
- b. With one SIT inoperable due to reasons other than those stated in ACTION-a, restore the inoperable SIT to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; otherwise, 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 /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
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EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE RE UIREMENTS (Continued)
- b. At least once per 31 days and within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after each solution
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volume increase of > 1% of tank volume by verifying the boro concentration of the safety injection tank solution. This atte~
surveillance is not required when the volume increase makeup source is the RMT and the RN'as not been diluted since verifying that the RWT boron concentration is equal to or greater than the safety injection tank boron concentration limit.
- c. At least once per 31 days when the RCS pressure is above 1750 psia, by verifying that power to the isolation valve operator is removed by maintaining the breaker open under administrative control.
- d. At least once per 18 months by verifying that each safety injec-tion tank isolation va ve o ens automatically under each of the following conditions
- 1. When the RCS pressure exceeds 350 psia, and JOE LPyr
- 2. Upon receipt of a safety injection test signal.
ST. LUCIE - UNIT 1 3/4 5-2 Amendment No.
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3/4.5 EMERGENCY CORE COOLING SYSTEMS ECCS BASES 3 4.5.1 SAFETY INJECTION TANKS The OPERABILITY of each of the RCS safety injection tanks ensures hat a sufficient volume of borated water will be immediately forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of the safety injection tanks. This initial surge of water into the core provides the initial cooling echanism during large RCS pipe ruptures.
The limits sn safety injection tank volume, boron concentration and pressure ensure that the assumptions used for safety injection tank injection in the accident analysis are met.
i 'ne njection tank minimiz hour for operation with an the- ex os f-th inopera ant to a LOCA event ccurring concurrent w h failur o an dditia safety injection tan hic es in unacceptable peak cladding tempera es.
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@Nod-C 4.5.2 and 3 4.5.3 ECCS SUBSYSTEMS The OPERABILITY of two separate and independent ECCS subsystems nsures that sufficient emergency core cooling capability will be avail-ble in the event of a LOCA assuming the loss of one subsystem through ny single failure consideration. Either subsystem operating in conjunc-tion with the safety injection tanks is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double ended break of the largest RCS cold leg pipe downward. In addition, each, ECCS subsystem provides long term core cooling capability in the recirculation ode during the accident recovery period.
The Surveillance Requirements provided to ensure OPERABILITY of ach component ensure that at a minimum, the assumptions used in the ccident analyses are met and that subsystem OPERABILITY is maintained.
The limitations on HPSI pump operability when the RCS temperature is ( 270'F and ( 236'F, and the associated Surveillance Requirements provide additional administrative assurance that the pressure/temperature limits (Figures 3.4-2a and 3.4- b) will not be exceeded during a mass addition transient mitigated by a single PORV.
T. LUCIE - UNIT 1 B 3/4 5-1 Amendment Nn. ~,AA
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St. Lucie Unit 1 and Unit 2 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension The limit of 72 hours for operation with an SIT that is inoperable due to boron concentration not within limits, or due to the inability to verify liquid volume or cover-pressure, considers that the volume of the SIT is still available for injection in the event of a LOCA. If one SIT is inoperable for other reasons, the SIT may be unable to perform its safety function and, based on probability risk assessment, operation in this condition is limited to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
St. Lucie Unit 1 and Unit 2 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension ATTACHMENT 4 ST. LUCIE UNIT 2 MARKED-UP TECHNICAL SPECIFICATION PAGES Page 3/4 5-1 INSERT-A/INSERT-B Page 3/4 5-2 Page B 3/4 5-1 INSERT C
3/4.5 EMERGENCY CORE COOLING SYSTEMS ECCS 3/4.5.1 SAFETY INJECTION TANKS (5 A )
LIMITING CONDITION FOR OPERATION 3.5.1'ach Reactor Coolant System safety injection tank shall be OPERABLE with:
- a. The isolation valve .open,
- b. A contained borated water volume of between 1420 and 1556 cubic feet,
- d. A nitrogen cover-pressure of between 500 and 650 psig.
APPLICABILITY: MODES 1, 2., 3", and 4".
ACTION:
44 safety injection tank inoperable, except as a closed isola sonmalve~estore th opera ank to OPERABLE status within 1 ~v-b~n a least-HOT STANDBY within the next our n HOT SHUTDOWN within the following hou ith-on safety injection tank inoperable due to the i ~flVe being close, esther-immediately~oe~he-i~o1 1on valve or be in at least HOT S~TNOBY-withi~ lioU~nd>>b HOT SHUTDOWN within h~ext 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
SURVEILLANCE RE UIREMENTS 4.5. 1. 1 Each safety injection tank shall be demonstrated OPERABLE:
- a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by:
~gg vt 1 ~ Verif in h~b n the contained borated 4 Q+
water volume and nitrogen cover-pressure in the tank , and ~< IAL 1
- 2. Verifying that each safety injection tank isolation valve is open.
With pressurizer pressure greater than or equal to 1750 psia. When pressur izer pressure is less than 1750 psia, at least three safety injection tanks shall be OPERABLE, each with a minimum pressure of 235 psig and a maximum pressure of 650 psig and a contained water volume of between 1250 and 1556 cubic feet with a boron concentration of between 1720 and 2100 ppm of boron.
With all four safety injection tanks OPERABLE, each tank shall have a minimum pressure of 235 psig and a maximum pressure of 650 psig and a contained water volume of between 833 and 1556 cubic feet with a boron concentration of between 1720 and 2100 ppm of boron. In MODE 4 with pressurizer pressure less than 276 psia, the safety injection tanks may be isolated.
ST. LUCIE - UNIT 2 3/4 5-1 Amendment No.gg;P8",
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St. Lucie Unit 1 and Unit 2 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension I ERT-A a~ With one SIT inoperable due to boron concentration not within limits, or due to an inability to verify the required water volume or nitrogen cover-pressure, restore the inoperable SIT to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />; otherwise, 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 /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
INSERT - B
- b. With one SIT inoperable due to reasons other than those stated in ACTION-a, restore the inoperable SIT to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; otherwise, 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 /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
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EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REOUIREMENTS (Continued)
- b. At least once per 31 days and within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after each solution volume increase of greater than or equal to LC of tank volume by verifying the boron concentration of the safety injection tank solution. This surveillance is not required when the volume increase ma eup source is the RMT and the RMT has not been diluted since verifying that the RMT boron concentration is equal to or greater than the safety injection tank boron concentration limit.
C. At least once per 31 days when the 'RCS pressure is above 700 psia, by verifying that, power to the isolation valve operator is disconnected by maintaining the breaker open by administrative controls.
- d. At least once per 18 months by verifying that each safety injection tank isolation valve opens automatically under each of the following conditions:
- I. When an actual or simulated RCS pressure signal exceeds 515 psia, and
- 2. U p on t recei p of a safet in 3 ection test si g nal.
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-CALISRATION Amendment No.
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3/4.5 EMERGENCY CORE COOLING SYSTEMS (ECCS)
BASES 3/4. 5. 1 SAFETY'NJECTION TANKS The OPERABILITY of each of the Reactor Coolant System (RCS) safety injection tanks ensures that a sufficient volume of borated water will be immediately forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of the safety injection tanks. This initial surge of water into the core provides the initial cooling mechanism during large RCS pipe ruptures.
The limits on safety injection tank volume, boron concentration, and pressure ensure that the assumptions used for safety injection tank injection in the safety analysis are met.
The safety injection tank power-operated isolation valves are considered to be "operating bypasses" in the context of IEEE Std. 279-1971, which requires that bypasses of a protective function be removed automatically whenever permissive conditions are not met. In addition, as these safety injection tank isolation valves fail to meet single failure criteria, removal of power to the valves is required.
reason except plant to a a
'ion 'cur rent its for operation with event occu valve a safety injection tank inoperable closed minimizes the tim with of an e of the additional safety injection tank which may result in - le peak cladding temperatures.
If a closed isolation v not be immediate ed, the full capability
's required to of one safet ion tank is not available and prompt a e reactor in a mode where this ca abilit is not re uired 3/4.5.2 and 3/4.5.3 ECCS SUBSYSTEMS The OPERABILITY of two separate and independent ECCS subsystems ensures that sufficient emergency core cooling capability will be available in the event of a LOCA assuming the loss of one subsystem through any single failure consideration. Either subsystem operating in conjunction with the safety injection tanks is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double-ended break of the largest RCS hot leg pipe downward. In addition, each ECCS subsystem provides long-term core cooling capability in the recirculation mode during the accident recovery period.
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St. Lucie Unit 1 and Unit 2 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension INSERT-The limit of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for operation with an SIT that is inoperable due to boron concentration not within limits, or due to the inability to verify liquid volume or cover-pressure, considers that the volume of the SIT is still available for injection in the event of a LOCA. If one SIT is inoperable for other reasons, the SIT may be unable to perform its safety function and, based on probability risk assessment, operation in this condition is limited to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
St. Lucie Unit 1 and Unit 2 L-95-134 Docket Nos. 50-335 and 50-389 Proposed License Amendments Safet In'ection Tank AOT Extension ENCLOSURE Joint Applications Report for SAFETY INJECTION TANK AOT/STI EXTENSION CE NPSD-994, Final Report CEOG Task 836; May, 1995, with PSL1 and PSL2 corrections to Table 6.3.2-1
ATTACHMENTA "Mark-up" of NUREG-1432 SECTIONS 3.5.1 & B 3.5.1
SITs 3.5.1 3.5 EHERGENCY CORE COOLING SYSTEHS (ECCS) 3.5.1 Safety Injection Tanks (SITs)
LCO 3.5.1 [Four] SITs shall be OPERABLE.
APPLICABILITY: MODES 1 and 2, MODE 3 with pressurizer pressure ~ [700] psia.
ACTIONS COND I T ION RE(UIRED ACTION COHPLET ION TIME A. One SIT inoperable due A. 1 Restore boron 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to boron concentration concentration to not within limits. within limits.
I-j( One SIT inoperable reasons other than for Restore SIT to OPERABLE status.
MM ~q-mrs Condition D
Required Action and P.l Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition A AND or B not met. D p.E Reduce pressurizer 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> pressure to
< L'700] psia.
E Two or more SITs P.l Enter LCO 3.0.3. Imnediately inoperable.
GEOG STS 3.5-1 Rev. 0, 09/28/92
INSERT A B. One SIT inoperable due B.1 Restore SIT to OPERABLE .72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to inability to verify level status.
or pressure.
BASES ACTIONS A.l (continued) injection. Thus, 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is allowed to return the boron concentration to within limits.
ZNScPT H8 If one is inoperable, for a reason other than on concentratio , the SIT must be returned to OP BLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. this Condition, the r ~red contents of three SITs cannot be umed to rea e core during a LOCA. Due to the severit f consequences should a LOCA occur in these conditions hour Completion Time to open the valve, remov ower to t alve, or restore the proper water vol or nitrogen cover sure ensures that prompt aetio ill be taken to return the > erable accumul to OPERABLE status. The Completion e min zes the exposure of the plant to a LOCA in the nditions.
.1 and .2 If the SIT cannot be restored to OPERABLE status within the associated Completion Time, the plant must be brought to a HOOE in which the LCO does not apply, To achieve this status, the plant must be brought to at least HOOE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and pressurizer pressure reduced to < 700 psia within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.
If more than one SIT is inoperable, the unit is in a condition outside the accident analyses. Therefore, LCO 3.0.3 must be entered inmediately.
(continued)
CEOG STS B 3.5-7 Rev. 0, 09/28/92
INSERT AA B1 Section 7.4 of Reference 5, NUREG-1366, discusses surveillance requirements in technical specifications for the instrument channels used in the measurement of water level and pressure in SITs.
The following statement is made in Section 7.4 of Reference 5:
'Me combination of redundant level and pressure instrumentation [for any single SIT] may provide sufficient information so that it may not be worthwhile to always attempt to correct drift associated with one instrument [with resulting radiation exposures during entry into containment] if there were sufficient time to repair one in the event that a second one became inoperable. Because these instruments do not initiate a safety action, it is reasonable to extend the allowable outage for them.
The [NRC] staff, therefore, recommends that an additional condition be established for the specific case, where "One accumulator [SIT] is inoperable due to the inoperability of water level and pressure channels,"
in which the completion time to restore the accumulator to operable status will be 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. While technically inoperable, the accumulator would be available to fulfillits safety function during this time and, thus, this change would have a negligible increase in risk."
INSERT AB If one SIT is inoperable, for a reason other than boron concentration or the inability to verify level or pressure, the SIT must be returned to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. In this Condition, the required contents of three SITs cannot be assumed to reach the core during a LOCA as is assumed in Appendix K to 10 CFR 50.
Reference 6 provides a series of deterministic and probabilistic Qndings that support 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as being either "risk bene6cial" or "risk neutral" in comparison to shorter periods for restoring the SIT to OPERABLE status. Reference 6 discusses best-estimate analysis that confirmed that, during large-break LOCA scenarios, core melt can be prevented by either operation of one Low Pressure Safety Injection (LPSI) pump or the operation of one High Pressure Safety Injection (HPSI) pump and a single SIT. Reference 6 also discusses plant-specific probabilistic analysis that evaluated the risk-impact of the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> recovery period in comparison to shorter recovery periods.
SITs 8 3.5.1 BASES (continued)
SURVEILLANCE SR 3.5.1.1 RE(UIREHENTS Verification every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> that each SIT isolation valve is fully open, as indicated in the control room, ensures that SITs are available for injection and ensures timely discovery if a valve should be partially closed. If an isolation valve is not fully open, the rate of injection to the RCS would be reduced. Although a motor operated valve should not change position with power removed, a closed valve could result in not meeting accident analysis assumptions. A 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency is considered reasonable in view of other administrative controls that ensure the unlikelihood of a mispositioned isolation valve.
SR 3.5.1.2 and SR 3.5.1.3 SIT borated water volume and nitrogen cover pressure should be verified to be within specified limits every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> in order to ensure adequate injection during a LOCA. Oue to the static design of the SITs, a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency usually allows the operator sufficient time to identify changes before the limits are reached. Operating experience has shown this Frequency to be appropriate for early detection and correction of off normal trends.
SR 3.5.1.4 Thirty-one days is reasonable for verification to determine that each SIT's boron concentration is within the required limits, because the static design of the SITs limits the ways in which the concentration can be changed. The 31 day Frequency is adequate to identify changes that could occur from mechanisms such as stratification or inleakage.
Sampling the affected SIT within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after a 1~ volume increase will identify whether inleakage has caused a reduction in boron concentration to below the required limit. It is not necessary to verify boron concentration the added water is from the RMT, because the water contained if in the RMT is within the SIT boron concentration requirements. This is consistent with the recommendations of NUREG-1366 (Ref. 5).
(continued)
CEOG STS 8 3.5-8 Rev. 0, 09/28/92
INSERT AC
, Reference 6, and Reference 7.
SITs B 3.5.1 BASES SURVEILLANCE SR 3.5.1.5 RE(UIREHENTS (continued) Verification'every 31 days that power is removed from each SIT isolation valve operator when the pressurizer pressure is ~ 2000 psia ensures that an active failure could not result in the undetected closure of an SIT motor operated isolation valve. If this were to occur, only two SITs would be available for injection, given a single failure coincident with a LOCA. Since installation and removal of power to the SIT isolation valve operators is conducted under administrative control, the 31 day Frequency was chosen to provide additional assurance that power is removed.
This SR allows power to be supplied to the motor operated isolation valves when RCS pressure is < 2000 psia, thus allowing operational flexibility by avoiding unnecessary delays to manipulate the breakers during unit startups or
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shutdowns. Even with power supplied to the valves, inadvertent closure is prevented by the RCS pressure interlock associated with the valves. Should closure of a valve occur in spite of the interlock, the SI signal provided to the valves would open a closed valve in the event of a LOCA.
REFERENCES ). IEEE Standard 279-1971.
- 2. FSAR, Section [6.3] .
- 3. 10 CFR 50.46.
- 4. FSAR, Chapter [15].
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INSERT AD
- 6. NRC Generic Letter 93-05, "Line-Item Technical Specifications Improvements To Reduce Surveillance Requirements For Testing During Power Operations," September 27, 1993