ML20203J921

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Forwards Corrected Proposed Tech Spec Changes,Modifying Containment Pressure Setpoint & Deleting Biweekly MSIV Surveillance,Per NRC Review Identifying Administrative/ Typographical Errors in 841127 Submittal
ML20203J921
Person / Time
Site: Quad Cities  Constellation icon.png
Issue date: 07/22/1986
From: Wojnarowski J
COMMONWEALTH EDISON CO.
To: Harold Denton
Office of Nuclear Reactor Regulation
References
1885K, NUDOCS 8608060075
Download: ML20203J921 (18)
v • d • e


Text

-

'9 - Commonweath Edison

, f4 72 West Adams Street, Chicigo, lilinois

"' Address Reply to: Post Offica Box 707 Chicago, lilinois 60690-0767 July 22, 1986 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Quad Cities Station Units 1 and 2 Supplement to Proposed Technical Specification Amendment - Containment Pressure Setpoint/MSL Isolation Valve Surveillance NRC Docket Nos. 50-254 and 50-265

Reference:

Letter from B. Rybak to H. R. Denton dated November 27, 1984.

Dear Mr. Denton:

The referenced letter proposed revised Technical Specifica-tions for Quad Cities Units 1 and 2 to modify the containment pressure setpoint and delete the bi-weekly main steam isolation valve surveillance. During your staff's review, a number of

administrative / typographical errors were identified. Attachments 1 i and 2 provide corrected copies of the proposed Technical i Specification changes for Units 1 and 2 respectively. These changes replace those transmitted with the referenced letter. Since this

! transmittal does not materially change the proposed amendment, our i previous technical justification and determination of No Significant i Hazards Consideration remains valid.

a

! Please direct any questions you may have concerning this j natter to this office.

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l PDR ADOCK 05000254 j P PDR i

Mr. H. R. Denton July 22, 1986 Three (3) signed originals and thirty-seven (37) copies of this transmittal and its attachment are provided for your use.

Very truly yours, s

1 J. R. Wojnarowski Nuclear Licensing Administrator 1m l

Attachment cc: NRC Resident Inspector - Quad Cities R. Bevan - NRR M. C. Parker - IDNS SUBSCRIBED AND S O to befo e m this & _ o day

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Om Notary Public

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ATTACHMENT 1 4

i PROPOSED CHANGES TO DPR-29 i

Revised Pages: 3.1/4.1-8 l 3.1/4.1-9

! 3.1/4.1-10 1

3.2/4.2-11 l 3.2/4.2-12 3.7/4.7-10 I 3.7/4.7-18 i

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QUAD-CITIES DPR-29 TABLE 3.1-1 REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENTATION REQUIREMENTS REFUEL MODE Minimum Number ~'

of Operable or Tripped Instrument Channels per Trio System (l) Trio Function Trio Level Setting Action (2) 1 Mode switch in shutdown A 1 Manual scram A 3 IRM High Flux A i 1.20/125 of full scale 3 Inoperative APRM(3) 2 High Flux (15% scram) Specification j 2.1.A.2 A 2 Inoperative A 2 (per bank) High water level in scram -< 40 gallons per bank A discharge volume (4) 2 High reactor pressure i 1060 psig A 2 High drywell pressure (5) i 2.5 psig A 2 Reactor low water level > 8 inches (8) A 2 Turbine condenser low -> 21 inches Hg vacuum A l vacuum (7) 2 Main steamline high < 7 X normal full power A radiation (12) background A

4 Main steamline isolation -< 10% valve closure valve closure (7) l l

0538H 3.1/4.1-8 Amendment No.

1 I

l

. QUAD-CITIES OPR-29 TABLE 3.1-2 REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENTATION REQUIREMENTS STARTUP/ HOT MODE Minimum Number of Operable or Tripped Instrument Channels pe Trip System I) Trip Function Trio Level Setting Action (2) 1 Mode switch in shutdown A 1 Manual scram A IRM 3 High Flux i 110/125 of full scale A 3 Inoperative A APRM(3) 2 High Flux (15% scram) Specification 2.1.A.2 A 2 Inoperative r A 2 High-reactor pressure i 1060 psig A 2 High drywell pressure (5) i 2.5 psig A 2 Reactor low water level > 8 inches (8) A 2 (per bank) High water level in scram -< 40 gallons per bank A discharge volume <4) 2 Turbine condenser low -> 21 inches Hg vacuum A vacuum (7) 2 Main steamline high < 7 X normal full power A radiation (12) background Main steamline isolation A 4 -< 10% valve closure valve closure (7) 0538H 3.1/4.1-9 Amendment No.

QUAD-CITIES

- DPR-29 TABLE 3.1-3 REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENTATION REQUIREMENTS RUN MODE Minimum Number of Operable or Tripped Instrument Channels pe Trio System I) Trip Function Trio Level Setting Action (2)

A 1 Mode switch in shutdown A

1 Manual scram APRM(3) 2 High Flux (flow biased) Specification 2.1.A.1 A or 8 2 Inoperative A or B 2 Downscale (II) > 3/125 of full scale A or B 2 High-reactor pressure 1 1060 psig A 2 High drywell pressure 1 ,2.5 psig A 2 Reactor low water level > 8 inches (8) A 2 (per bank) High-water level in scram discharge volume 1 40 gallons per bank A 2 Turbine condenser low > 21 inches Hg vacuum A or C vacuum 2 Main Steamline high ( 7 X normal full power A or C radiation (12) power background 4 Main steamline isolation -< 10% valve closure A or C valve closure (6) 2 Turbine control valve fast > 40% turbine / enerator A or C Toadmismatch(g0) closure (9) 2 Turbine stop valve 1 10% valve closure A or C closure (9) 2 Turbine EHC control fluid ~> 900 psig A or C low pressure (9)

(

3.1/4.1-10 Amendment No.

0538H

QUAD-CITIES DPR-39 TABLE 3.2-1 INSTRUMENTATION THAT INITIATES PRIMARY CONTAINMENT !$0LATION FUNCTIONS Minimum Number of Operable or Tripped Instrumept, ChannelsLLA Instruments Trio Level settina Action M 4 Reactor low water [5] >144 inches above top of A active fuel

  • 4 Reactor low low water 2.84 inches above top of A active fuel
  • 4 High drywell pressure [5] 12.5 psig I33 A 16 High flow main steamline[5] 11407,of rated steam flow 8 16 High temperature main 1200 0 F 8 steamline tunnel 4 Highradiationmpgg 17 r normal rated power 8 steam 11ne tunnell J background 4 Low main steam pressureI43 2.825 psig 8 4 High flow RCIC steamline 1300(y)ofratedsteam C flow 16 RCIC turbine area high 1200 0 F C temperature 4 High flow HPCI steamline 1300y7gf rated steam D flow 3 16 HPCI area high temperature 1200 0 F D Notes
1. Whenever primary containment integrity is required, there shall be two operable or tripped systems for each function, except for low pressure main steamline which only need be available in the Run position.
2. Action. if the first column cannot be met for one of the trip systems, that trip system shall be tripped.

If the first column cannot be met for both trip systems, the appropriate actions i listed below shall be taken, l

i A. Inttiate an orderly shutdown and have the reactor in Cold Shutdown condition in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

l l B. Initiate an orderly load reduction and have reactor in Hot Standby within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

C. Close isolation valves in RCIC system.

D. Close isolation valves in HPCI subsystem.

3. Need not be operable when primary containment integrity is not required.
4. The isolation trip signal is bypassed when the mode switch is in Refuel or Startup/

Hot Shutdown.

5. The instrumentation also isolates the control room ventilation system.

! 6. This signal also automatically closes the mechanical vacuum pump discharge line iso-L, lation valves.

7. Includes a time delay of 3 i t i 10 seconds.

l Top of active fuel is defined as 360* above vessel zero for all water levels used in the l

LOCA analysis (see Bases 3.2).

0539H 3.2/4.2-11 Amenenent No.

I

. . _ - . . . . . _ , - _ - - - . . . . . . - ~ - . _ , . -. . - . . _ . . . - _ _

QUAD-CITIES DPR-29 TABLE 3.2-2 INSTRUMENTATION THAT INITIATES OR CONTROLS THE CORE AMO CONTAINMENT COOLING SYSTEMS Minimum Number of Operable or Tripped Instrume

  • Channels Trio Function Trio Level Settina Remarks 4 Reactor low low 184 inches (+ 4 1. In conjunction with low-water level inches /-0 inch) reactor pressure initiates above top of core spray and LPCI.

active fuel

  • 2. In conjunction with high-drywell pressure 120-second time delay and low-pressure core cooling interlock inttt-ates auto blowdown.
3. Initiates HPCI and RCIC.
4. Initiates starting of diesel generators.

4[4] High-drWg1I3I 12.5 psig 1. Initiates corre spray. LPCI, pressuret HPCI, and SGTS.

2. In conjunction with low low water level,120-second time delay, and low-pressure core cooling interlock initiates auto blowdown.
3. Initiates starting of diesel generators.
4. Initiates isolation of control room ventilation.

2 Reactor low 300 psigip1350 psig 1. Permissive for opening core pressure spray and LPCI ammission valves.

2. In conjunction with low low reactor water level initiates core spray and LPCI.

Containment spray Prevents inadvertent operation of interlock containment spray during accident conditions.

2I3} 2/3 core height 12/3 core height

, 4[3] containment 0.5 psigipil.5 psig high pressure 1

2 Timer auto 1120 seconds In conjunction with low low blowdown reactor water level high-drywell pressure, and low-pressure core cooling interlock initiates auto blow-down.

4 Low-pressure 100 psigip1150 psig Defers APR actuation pending con-core cooling pump firmation of low-presure core discharge pressure cooling system operation.

2/8US [5] Undervoltage on 3045 1 5% volts 1. Initiates starting of diesel emergency buses generators.

2. Permissive for starting ECCS pumps.
3. Removes nonessential loads from buses
4. Bypasses degraded voltage timer.
  • Top of active fuel is defined at 360* above vessel zero for all water levels used in the LOCA analysis 0539H 3.2/4.2-12 Amendment No.

l QUAD-CITIES DPR-29 reopened.

2) The main steamline isolation valves (one at a time) shall be verified for closure time. -
2. In the event any isolation valve 2. When an isolation valve listed specified in Table 3.7-1 becomes in Table 3.7-1 is inoperable, inoperable, reactor power opera- the position of at least one tion may continue provided at other valve in each line having least one valve in each line an inoperable valve shall be having an inoperable valve is in recorded daily.

the mode corresponding to the isolated condition.

3. If Specifications 3.7.D.1 and 3.7.D.2 cannot be met, an orderly shutdown shall be initi-ated and the reactor shall be in '

the cold shutdown condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

4. The temperature of the main stearaline air pilot valves shall be less than 1700F except as specified in Specifications 3.7.D.5 and 3.7.D.6 below.
5. From and after the date that the temperature of any main steam-line air pilot valve is found to be greater than 1700F reactor operation is permissible only during the succeeding 7 days unless the temperature of such valve is sooner reduced to less than 1700F provided the main steamline isolation valves are operable.
6. If Specification 3.7.D.5 cannot i be met, the main steamline isolation valve shall be considered inoperable and action taken in accordance with Specification 3.7.0.2.

l l 0540H 3.7/4.7-10 Amendment No.

l

QUAD-CITIES DPR-29 will be replaced with filters qualified pursuant to regulatory guide position C.3.d. of Regulatory Guide 1.52 Revision 1 (June 1976). Once per operating cycle demonstration of HEPA filter pressure drop, operability of inlet heaters at rated power, air distribution to each HEPA filter, and automatic initiation of each standby gas treatment system circuit is necessary to assure system performance capability). Note: bases within parentheses will not be applicable until about December 31, 1976, when equipment modifications are completed to allow increased testing.

D. Primary Containment Isolation Valves Those large pipes comprising a portion of the reactor coolant system, whose failure could result in uncovering the reactor core, are supplied with auto-matic isolation valves (except those lines needed for emergency core cooling system operation or containment cooling). The closure times specified herein are adequate to prevent loss of more coolant from the circumferential rupture of any of these lines outside the containment than from a steamline rupture.

Therefore, this isolation valve closure time is sufficient to prevent un-covering the core.

In order to assure that the doses that may result from a steamline break do no exceed the 10 CFR 100 guidelines, it is necessary that no fuel rod per-foration resulting from the accident occur prior to closure of the main steam line isolation valves. Analyses indicate that fuel rod cladding perforations would be avoided for main steam valve closure times, including instrument delay, as long as 10.5 seconds. However, for added margin, the technical specifications require a valve close time of not greater than 5 seconds.

For reactor coolant system temperature less than 2120F, the containment could not become pressurized due to a loss-of-coolant accident. The 2120F limit is based on preventing pressurization of the reactor building and rup-ture of the blowout panels. These valves are hl'ghly reliable, have low ser-vice requirement, and most are normally closed. The initiating sensors and associated trip channels are also checked to demonstrate the capability for automatic isolation (reference SAR Section 5.2.2 and Table 5.2.4).

The test interval at once per operating cycle for automatic initiation re-suits in a failure probability of 1.1 x 10-7 that a line will not isolate.

More frequent testing for valve operability results in a more reliable sys- -

tem.

The containment is penetrated by a large number of small diameter instrument lines which contact the primary coolant system. A program for periodic testing and examination of the flow check valves in these lines is performed by blowing down the instrument line during a vessel hydro and observing the following conditions, which will verify that the flow check valve is operable:

?

0540A 3.7/4.7-18 Amendment No.

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L i Revised Pages: 3.1/4.1-8 i 3.1/4.1-9

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b QUAD-C8 TIES DPR-30 TABLE 3.1-1 REACTOR PROTECTION SYSTCM (SCRAM) INSTRUMENTATION REQUIREMENTS REFUEL MODE Minimum Number of Operable or Tripped Instrument Channels per Trin svitan(I) Trio Function Trin Level settina &c11gn(2)

A 1 Mode Switch in shutdown Manual scram A 1

IRM 3 High flux i 120/125 of full scale A 3 Inoperative APRM(3) 2 High flux (15% scram) Specification 2.1.A.2 A Inoperative A 2

2 (per bank) High water level in scram i 40 gallons per bank A discharge volume (4)

High-reactor pressure i 1060 psig A 2

2 High-drywell pressure (5) i 2.5 psig A Reactor low water level 1 8 inches (8) A 2

2 Turbine condenser low 1 21 inches Hg vacuum A vacuumI7) 2 Main steamline high i 7 X normal full power A radiation (12) background i 10% valve closure A 4 Main steamline isolation valve closure (7) 3.1/4.1-8 0154H/00682 Amenenent No.

QUAD-CITIES

  • DPR-30 TABLE 3.1-2 REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENTATION REQUIREMENTS STARTUP/ HOT STAND 8Y MODE Minimum Number of Operable or Tripped Instrument Channels per Trin system (l) Trin Function Trio Level settina Action (2)

A 1 Mode Switch in shutdown Manual scram A 1

IRM 3 High flux i 120/125 of full scale A A

3 Inoperative APRM(3)  !

High flux (15% scram) Specification 2.1.A.2 A 2

Inoperative A 2

i 1060 psig A 2 High-reactor pressure A

2 High-drywell pressure (5) i 2.5 psig A

2 Reactor low water level 1 8 inches (8) 2 (per bank) High water level in scram 1 40 gallons per bank A discharge volumeI4I 2 Turbine condenser low 1 21 inches Hg vacuum A vacuum (7) 2 Main steamline high i 7 X normal full power A radiation (12) background A

4 Main steamline tsolation i 10% valve closure valve closure (73 3.1/4.1-9 Amenenent No.

0154H/0068Z

QUAD-CITIES

  • OPR-30 TABLE 3.1-3 REACTOR PROTECTION SYSTEM (SCRAM) INSTRUMENTATION REQUIREMENTS RUN MODE Minimum Number of Operable or Tripped Instrument Channels per Trin System (I) Trin Function Trin Levet Settina Action (2)

A 1 Mode Switch in shutdown A

1 Manual scram APRM(3I 2 High flux (flow biased) Specification 2.I.A.I A or 8 Inoperative A or 8 2

Dewnscaleill) 1 3/125 of full scale A or B 2

A 2 High-reactor pressure i 1060 psig A

2 High-drywell pre'sure s i 2.5 psig 1 8 inches (8) 4 2 Reactor low water level 2 (per bank) High-water level in scram i 40 gallons per bank A discharge volume Turbine condenser low 1 21 inches Hg vacuum A or C 2

vacuum Main steinline high i 7 X normal full power A or C 2

radiation (12) background i

4 Main steamline isolation i 10% valve closure A or C valve closure (6)

Turbine control valve fast 140% turbtne/ generator A or C 2

closureI9) load mismatch (10)

Turbine stop valve i 10% valve closure A or C 2

! closure (9)

Turbine EHC control fluid 1 900 psig A or C 2

low pressure (9) l I

3.1/4.1-10 Amenenent No.

OlS4H/00682

QUAD-CITIES

. DPR-30 TABLE 3.2-1 INSTRUMENTATION THAT INITIATES PRIMARY CONTAIMMENT ISOLATION FUNCTIONS Minimum Number of Operable or Tripped Instrumep$,

thannels w Instruments Trio Level Settina ActionEId 4 Reactor low water [5] >144 inches above top of A active fuel

  • 4 Reactor low low water 184 inches above top of A active fuel
  • 4 High drywell pressure [5] 12.5 ssig E33 A 16 High flow main steam 11ne[5] 1140% of rated steam flow B 16 High temperature main 1200 0 F B stcamline tunnel 4 Highradiationggg 17 x normal rated power B steamitne tur.nelt 3 background 4 Low main steam pressureI43 1825 psig B 4 High flow RCIC steamitne of rated steam C 1300(}I flow i

16 RCIC turbine area high 1200 0 F C temperature 4 High flow HPCI steam 11ne 1300'(logf rated stemn D

flow 16 HPCI area high tenperature 1200 0 F 0 Notes

1. Whenever primary containment integrity is required, there shall be two operable or tripped systems for each function except for low pressure main steamline which only need be available in the Run position.
2. Action, if the first column cannot be met for one of the trip systems, that trip system shall be tripped.

If the first column cannot be met for both trip systems, the apprcpriate actions listed below shall be taken.

A. Initiate an orderly shutdown and have the reactor in Cold Shutdown condition in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

8. Initiate an orderly load reduction and have reactor in Hot Standby within B

, bours.

C. Close isolation valves in RCIC system.

l l 0. Close isolation valves in HPCI subsystem.

t

3. Need not be operable when primary containment integrity is not required.
4. The isolation trip signal is bypassed when the mode switch is in Refuel or Startup/

Hot Shutdown.

l

5. The instrumentation also isolates the control room ventilation system.
6. Yhts signal also automatically closes the mechanical vacuum pump discharge line iso-lation valves.

I 7. Includes a time delay of 3 1 t i 10 seconds.

Top of active fuel is defined as 360* above vessel zero for all water levels used in the LOCA analysis (see Bases 3.2).

0539H 3.2/4.2-11 Amendment No.

+ QUAD-CITIES OPR-30 TABLE 3.2-2 INSTRUMENTATION THAT INITIATES OR CONTROLS THE CORE AND CCNTAINMENT COOLING SYSTEMS Minimum Number of Operable or Tripped Instrume channels Trio Function Trio tevel settina Remarks 4 Reactor low low 184 inches (+ 4 1. In conjunction with low-water level inches /-0 inch) reactor pressure initiates above top of core spray and LPCI.

active fuel

  • 2. In conjunction with high-drywell pressure 120-second time delay and low-pressure core cooling interlock intti-ates auto blowdown.
3. Initiates HPCI and RCIC.
4. Initiates starting of diesel generators.

4(41 12.5 psig 1. Initiates core spray LPCI, High-drng1*

pressurel E33 HPCI. and SGTS.

2. In conjunction with low low water level 120-second time delay and low-pressure core cooling interlock inittates auto blowdown.
3. Initiates starting of diesel generators.
4. Initiates isolation of control room ventilation.

2 Reactor low 300 psigipi350 psig 1. Permissive for opening core pressure spray and LPCI aenission valves.

2. In conjunction with low low reactor water level initiates core spray and LPCI.

Containment spray Prevents inadvertent operation of interlock containment spray during accident conditions.

2I3I 2/3 core height 12/3 core height 4[3} contatnment 0.5 pstgipil.5 psig high pressure 2 Timer auto 1120 seconds In co9 junction with low low blowdown reactor water level, high-drywell pressure, and low-pressure core cooling interlock inittates auto blow-down.

4 Low-pressure 100 psigip1150 psig Defers APR actuation pending con-core cooling pump firmation of low-presure core discharge pressure cooling systen operation.

2/ BUS (S] Undervoltage on 3045 i 5% volts 1. Initiates starting of diesel emergency buses generators.

2. Permissive for starting ECCS pumps.
3. Removes. nonessential loads from buses
4. Bypasses degraded voltage timer.
  • Top of active fuel is defined at 360* above vessel zero for all water levels used in the LOCA analysis 3.2/4.2-12 Amendment No.

0539H

QUAD-CITIES DPR-30 reopened.

2) The main steamline isolation valves (one at a time) shall be verified for closure time. -
2. In the event any isolation valve 2. When an isolation valve listed specified in Table 3.7-1 becomes in Table 3.7-1 is inoperable, inoperable, reactor power opera- the position of at least one tion may continue provided at other valve in each line having least one valve in each line an inoperable valve shall be having an inoperable valve is in recorded daily.

the mode corresponding to the isolated condition.

3. If Specifications 3.7.D.1 and 3.7.D.2 cannot be met, an orderly shutdown shall be initi-ated and the reactor shall be in r

the cold shutdown condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

4., Tha temperature of the main steamline air pilot valves shall be less than 1700F except as specified in Specifications 3.7,0.5 and 3.7.D.6 below.

5. From and after the date that the temperature of any main steam-line air pilot valve is found to be greater than 1700F reactor operation is permissible only during the succeeding 7 days unless the temperature of such valve is sooner reduced to less than 1700F provided the main steamilne isolatloa valves are operable.
6. If Specification 3.7.0.5 cannot be met, the main steamline isolation valve shall be considered inoperable and action taken in accordance with Specification 3.7.D.2.

0540H 3.7/4.7-10 Amendment No.

QUAD-CITIES OPR-30 will be replaced with filters qualified pursuant to regulatory guide position C.3.d. of Regulatory Guide 1.52 Revision 1 (June 1976). Once per operating cycle demonstration of HEPA filter pressure drop, operability of inlet heaters at rated power, air distribution to each HEPA filter, and automatic initiation of each standby gas treatment system circuit is necessary to assure system performance capability). Note: bases within parentheses will not be applicable until about December 31, 1976, when equipment modifications are completed to allow increased testing.

D. Primary Containment Isolation Valves Those large pipes comprising a portion of the reactor coolant system, whose failure could result in uncovering the reactor core, are supplied with auto-matic isolation valves (except those lines needed for emergency core cooling system operation or containment cooling). The closure times specified herein are adequate to prevent loss of more coolant from the circumferential rupture of any of tnese lines outsloe the containment than from a steamline rupture.

Therefore, this isolation valve closure time is sufficient to prevent un-covering the core.

In order to assure that the doses that may result from a steamline break do no exceed the 10 CFR 100 guidelines, it is necessary that no fuel rod per-foration resulting from the accident occur prior to closure of the main steam line isolation valves. Analyses indicate that fuel rod cladding perforations would be avoided for main steam valve closure times, including instrument delay, as long as 10.5 seconds. However, for added margin, the technical specifications require a valve close time of not greater than 5 seconds.

For reactor coolant system temperature less than 2120F, the containment could not become pressurized due to a loss-of-coolant accident. The 2120F limit is based on preventing pressurization of the reactor building and rup-ture of the blowout panels. These valves are highly reliable, have low ser-vice requirement, and most are normally closed. The initiating sensors and

. associated trip channels are also checked to demonstrate the capability for automatic isolation (reference SAR Section 5.2.2 and Table 5.2.4).

The test interval at once per operating cycle for automatic initiation re-suits in a failure probability of 1.1 x 10-7 that a line will not isolate.

More frequent testing for valve operability results in a more reliable sys-tem.

The containment is penetrated by a large number of small diameter instrument lines which contact the primary coolant system. A program for periodic testing and examination of the flow check valves in these lines is performed by blowing down the instrument line during a vessel hydro and observi q the following conditions, which will verify that the flow check valve is o,'rable:

0540H 3.7/4.7-18 Amendment No.

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