ML20002E039

Forwards Proposed Change 27 to Permit Installation of Modified post-incident Spray Sys to Provide Redundancy Re Single Failure Criteria & Vessel Jump Accident

ML20002E039
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	02/02/1971
From:	Haueter R, Wall H CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	Morris P, Skovholt D US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20002E040	List: ML20002E039 ML20002E048
References
NUDOCS 8101260169
Download: ML20002E039 (23)

Text

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General Offices: 212 Weu

.m. gen Avenue, Jackson, Michigan 49201. Area Code 517 788-0550 C) tP February 2,1971 Regulatory Filo Cy.

Dr. P. A. Morris, Director Re: Docket 50-155 Division of Reactor Licensing DPR-6 ZEK United States Atomic Energy Proposed Tech Speci-fication Change 27 Commission Washington, DC 20545

Dear Dr. Morris :

Attention: Mr. D. J. Skovholt Transmitted herewith are three (3) executed and thirty-seven (37) conformed copies of a request for change to the Technical Specifications of License DPR-6, Docket No 50-155, issued to Con-sumers Power Company on May 1,1964, for the Big Rock Point Nuclear Plant.

This propteed change (No 27) will enable Consumers Power Company to complete nstallation and place into service at Big Rock Point a modified post-incident spray system designed to provide re-dundancy with respect to single failure criteria and a vessel jump accident.

The set points associated with the time delay for M07070 and M07071 and the valve position switch open limits for MO7051, M07061 and M0706h submitted in this proposed change (Section 6.1.h(d))

represent the best engineering estimates available as to proper set points. Testing following installation will be conducted to verify the ad.equacy of these set points. If a change is necessary, a fur-ther request for change to the technical specifications will be sub-mitted.

It is our intention to complete the modifications ci"cribed in this proposed change during our next refueling outage which is cur-rently scheduled for February 1971. We would, therefore, be most appre-clative of an expeditious handling of this Request for a Technical Specifications Change so that we might receive approval before March 1, 1971.

On June 29, 1970, the United States Atomic Energy Commission responded to our letter of February 9, 1970 which stated our intentions with respect to the installation of a Modified Core Spray System. In your letter, you requested further information regarding "small primary EC7 F ([Ia G//69 h

a 6 2

, Dr. P. A. Morris February 2, 1971 system breaks." This information is herewith submit +.ed as Appendix 2 to this Request for a Technical Specifications Change.

Yours very truly, e s'; '

RBS/db Robert L. Haueter e-Electric Production Superintendent - Nuclear

J t

CONSUMERS POWER COMPANY l

Docket No 50-155 Request for Change to the Technical Specifications Change No 27 License No DPR-6 For the reasons hereinafter set forth, the following changes to the Technical Specifications of License DPR-6 issued to Consumers

Power Company on May 1,1964, for the Big Rock Point Nuclear Plant, are requested:

I.

Changes A. 'In Section 3 5.l(d), change to read as follows :

" System Actuation 1 Set Automatic DC Operated, 1 Set Automatic AC Operated" B.

In Section 3 5 2(a), ch3,ge to read as follows:

" Automatic operation of the containment spray system and backup containment spray system involves a time delay not to exceed five minutes after system actuation to allow the operator to everride a possible spurious actuation. This time delay feature may be manually overriden to actuate the spray system prior to the expiration of the five-minute delay period."

C.

In Section h.l.2(a), add a new section between " Core Spray System" and " Core Spray Recirculation" as follows:

" Backup Core Spray System:

IYpe Sparger Nozzle Centered Over Core Capacity of Sparger, Gpm h70 Nozzle Pressure, Psia 115" D.

In Section 4.1.2(b), change to read as follows :

"(b) Operatirg Requirements A minimum of one reactor recirculating loop or its equivalent shall be used during all reactor power

n 2

operations when reactor power level is above 1.0 Mwt.

The maximum operating pressure and temperature shall be the same as the reactor vessel. The controlled rate of change of temperature in the reactor vessel shall be limited to 100 F per hour. All other compon-ents in the system shall be capable of following this temperature change rate. The safety relief valves shall be set appropriately for all planned reactor operating pressures so that the allowable pressure of 1870 psia (1700 plus 10%) in the nuclear steam supply system is not exceeded. Th' emergency condenser, core spray and backup core spray systems shall be operable and ready for service at all times during power operation. The core spray system and shutdown cooling system shall be operable and ready for service during refueling operations.

The primary coolant shall be sampled and analyzed daily during periods of power operation. The following are absolute limits which if exceeded shall necessitate reactor shutdown. Corrective action will necessarily be taken at more stringent limits to minimize the pos-sibility of these absolute limits cver being reached."

E.

In Section h.2.1(a), a6d the following items to the list of equip-ment which receive their power supply from the 125-volt d-c bat-tery system:

" Post-Incident Enclosure Spray Valves Core Spray Valves" F.

In Section h.2.6, change to read as follows :

" Fire Protection System In addition to furnishing water for conventional plant fire-fighting equipment, the fire protection system shall furnish water as follows :

Core Spray Cooling System Backup Core Spray Cooling System Containment Sphere Post-Incident Spray System Sackup Service Water System to the Containment Sphere

~l 3

One electric fire pump and one diesel fire pump, each rated at 1000 gpm, 254-foot head shall be provided.

The fire protection syr, tem shall be operable and ready for service during power operation and refueling operation."

In Section 6.1.2, " Reactor Safety System During Power Operation,"

G.

the tabulation has been changed as indicated by a double dash

(--) in front of the item.

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3

. l 4

6.1.2

' Reactor Safety' System During Power Operation

-The following tabulation gives the arrangement of the' reactor. safety system that shall be effective z

. 7 during power operation:

Trip Scram Contacts Coincidence Setting Warningi

~

Sensor and in Each

'in Each and Instmment.:

Annunciation Trip Device Channel Channel Tolerance Special Features

' Ranges' Trip Set-Point':

-High reactor pres-2 1 out of 2 30 I 5 psi above

. 1'OO-1TOO'psig ~

25 I 5 psitabovei E

sure (k pressure reactor operating.

reactor-opera- -

switches )

pressure ting pressure Iow -reactor water 2

1 cut of 2 Elevation 610' Closes containment

- Fixed level trip level'(h level 6" I 1 inch sphere isolation valves.

point no range' switches)

,If reactor pressure is less than 200 psig, actu-ates core spray system.

(Note: Spray water will not enter reactor vessel until reactor pressure drops below fire header pressure.);

. t Iow steam drum 2

1 out of 2 8.0 I 0 5 inches

-30" to +30"

-h" below oper-water level (h below operating vster ating level level switches) level Msin steam line 2

1 out of 2 50 I 5 percent of Position switch backup isolation full closure

- trains adjust-valve closure _(h able full valve position switches) travel-

.High condenser 2

1 out of 2 8.0 I O.5 inches Bypassed by pressure in-

'0 - 30" Hg vae pressure (4 pres-of Hg absolute terlock as described in

. sure switches) pressure Section 6.1 3 c.

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6.1-2,(Contd)

'l Trip Scram Contacts Coincidence Setting Warning Sensor and in Each in Each and Instrument'

' Annunciation Trip Device Channel Channel Tolerance Special Features

' Ranges Trip Set Point

(--)Highenclosure 2

1 cut of 2 15 1 0.v psi Closes containment l sphere 0 - 20 ' psig :

.g pressure (4 pres-'

above atmospheric, isolation valves. (Twoi

..sure switches) independent pressure I

switches actuate a time

]

mechanism that initiates containment spray system t

within 5 minutes unless the control is manually overridden.)

i High scram dump 2

1 out of 2 5/16 1 1/2 inch Alarms at-level of 10 Fixed level at

-10" 1 1/2" be-tank level (h~

below tank center inches below tank center

-trip pol'nt (no low tank center; level switches) line line.

range) line i

4 Recirculation line

- 12 1 set out Approximately 10 Position switch valves closed (two of 2 percent of full adjustable for sets of 6 position simultaneous clo-full valve switches in each sure of both dis-travel of 2 channels) charge or both-l suction valves or simultaneous clo-1 sure of the butter-fly valves to the positions comparable to a 55 percent de-crease in flow from full flow or any

. combination of two i

of these valves, one in each-loop.

f

. Loss of auxiliary 1

1 out of 1 52 I 20 volts Closes all automatically power supply actuated containment l

(voltage relay).

sphere isolation volves.

• ^

en

. 6.1.2 (Conta)

~ Trip Scram Contacts. Coincidence Setting

.-Warning..

Sensor. and in Each in Fr.ch and

.InstrumentJ Annunciation Trip Device Channel' Channel Tolerance Special Features Ranges-Trip Set Point "

High neutron flux 3

2 'out' of 3 120.1 5' percent'of. ' Interlocks prevent control, O to'125%.

jm

. (each of 3 power.

the o to 125 per-rod withdrawal as'de-range flux monitors

~ cent scale, or 38 ! ' scribed in Section 6.2.1.

has a trip contact 2 M rcent of the O in each channel) to h0 percent' scale (any range}

Protection against 3

1 downscale 5 percent low trip Except that the.three picoammeter circuit' 1 upscale and 1 additional downscale trips may be failure instrument at 120%

simultaneously bypassed high trip when the picoammeter range switches are.simultane-ouslyseg% power.

to operate below 40 x 10' The by-pass becomes ineffective when the range for any'of the detector" is set above i

the hO x 10 % power.

Short period (each 2

1 out of 2 10 I 2 second Placement of any 2 out of

- -100-see to 15'see interme-of intermediate period

'3 range switches of.the infinity to +10. 'diate range.

range Icg-N period high leval neutron flux.

seconds.

(There is also monitors has a trip channels in the power an annunciator contact in each range position will by-operated by the.

channel) paes this period trip start-up' channel fenture.

period-contr'ts.)

Manual scram 1

1 out of 1 (1 switch) os j-1 1

'k _ =

T 1H.

In Section 6.1.h:

1.

Renumber " resent ~ Section "6.1.h(b), Emergency Condenser Con- -

trol,". to "6.1.h(d), Emergency Condenser Control."

2.

Insert new paragraph 6.1.4(h) as follows :

"(b) Backup Core Spray System Control The backup core spray' system shall be automatically.

actuated by simultaneous tripping of the-reactor safety

~ system sensor ' low reactor water level' along with the

' low reactor pressure device' if the core spray sys-tem has not actuated (actuation being' determined by both core spray system admission valves being in the

' full open position). The ' low reactor pressure trip device' consists of a pressure switch interlock which prevents backup core spray system admission valves opening while reactor pressure is above ~ 150 psig."

3 Insert new Table 6.1.4(c).as follows :

"(c) Core Spray, Backup Core Spray, Containment Spray and Backuo Containment Spray System Set Points The following tabulation gives the actuation set points for devices associated with the core spray, backup core spray, containment spray and backup containment spray systems:

-Actuation Setting and-

-Sensor Contacts Tolerance Function Low reactor sater 2 switches / valve Elevation 610' Actuates M07051 ana 7061 level (4 level 1 out of 2 6" I 1 inch in conjunction with re-switches) coincidence actor pressure.

Low reactor water 2 switches / valve Elevation 610' Actuates M07070 and 7071 level (4 level' 1 out of 2 6" ! 1 inch in conjunction with re-switches )

coincidence actor pressure.

Low reactor pres-2 switches / valve 200 psig I 20 psi Actuates M07051 and 7061 sure switches.(h 1 out of 2 in conjunction with low

' pressure switches) coincidence reactor water level.

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i-Actuation

' Setting and Sensor Contacts Tolerance Function-

- Low reactor pressure 2 switches / valve 150 psig' I 20 psi Actuates-MOTOTO and.7071

~ switches 1 out of 2 in conjunction with low coincidence reactor level, valve po-sition of M07051 and 7061 and time delay.

4

-Valve position 2 - 2 of '2 -

75 - 100% of full ' Blocks automatically switches'M07051'a'nd.

required open actuation of'M07070 and 1

7061 (2 switches, 7071 when M07051 and one per' valve)-

7061 are full open.

~

~

4

- Time delay'(2 1 per valve 40 I 5 see Block' opening of M07070 switches) and 7071 until time de-l' lay elapses.

High enclosure pres-2 - 1 of 2 15 I'O.2 psig Actuates a time-delay sure switches (2-required mechanism that initiates-

^

pressure switches)

M07064 (containment spray system) within 5 minutes unless the con-trol is manually over-ridden.

_ High enclosure pres-2 - l'or 2 2.0 I 0.2_psig Actuates a_ time delay 1

sure switches _

required mechanism.that initiates.

M07068 (backup contain-ment spray system)within 5

five minutes unless-M07064 is open as the control is manually.

overridden.

Valve L position 1

75 - 100% of full Blocks automatic actua-4 switch M07064 open tion of M07068 when M07064 is full open."

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In Section 6.15(b), change to read as follows:

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"(b) - The core spray system, backup core spray. system and emergency condenser system control initiation sensors shall be functionally tested not less frequently than once every 12 months."

-J.

In Section 6.1.6, change to read as follows :

"The automatic actuation of the' containment spray system and the backup containment spray system shall occur within five minutes of _ the receipt of a high containment pressure signal if more than one-half of' the. fuel bundles in the core are

. zirconium-clad."

K.

In Section 8.2.1, delete Item 8.2.l(d).

II.

Discussion A.

System Description

1.

General The original Big Rock Point Plant post-incident cooling and core spray cooling systems each consisted of essentielly single systems with initial water supply from the plant fire protection system followed by water supply from the core spray recirculation system.

Each water-supply system had two full-capacity pumps which were arranged to supply water through an automatic and/or remote-manual' controlled pair of motor-operated valves, in series (M07051 and M07061), to the core spray or through an automatic and/or remote-manual controlled motor-operated single valve (M07064) to the enclosure spray nozzles. The backup enclosure sprey was provided with a ormally closed manual-operated valve.

4 New criteria requiring that safety related systems be designed with redundancy to meet the. single failure criteria for active components have resulted in required modifications of the two systems. The modifi-cations are covered belos and as shown on attached Drawing M-123, Rev 15 2.

Core Spray System A second core spray system (called the backup core spray t-a.

system) has been added and is in parallel with and redundant to the original core spray system. The water supply to the backup core spray system can be remote manually or automatically selected from either of the two existing h" and 6" fire system supply headers or from the core

m k.

'10 spray: recirculation system.

(See Paragraph b. ) Selection-of the supply source can be. accomplished' by-operating a new.a-c motor-ope' rated valve

?(M07069) cross connecting the two fire system supply -headers. M07069 f s actuated by remote-manual-controller RMC-5526 -located on the control i

-- board.

The' backup core spray system valves (M07070 Land M07071) are '

a-c motor operated and are,.therefore, redundant Jto the existing d-c operated' valves (M07051 and M07061). Operation of the backup core spray-system valves is automatically initiated by primary system level switch upon water level falling below 610'-6", and concurrent permissive pres-sure switch action at less than 150 psig. Automatic operation of the backup core spray system valves will be blocked if both M07051 and M07061 are open. _ In addition, to prevent automatic initiation from opening both core spray system valves and both backup core spray system valves at the same time, a time delay is installed in the backup core spray system valves circuitry. Primary system level switches LS-RE09E,F,G,&H and pressure switches PS-1G11E,F,G,&H have been added and are separate and redundant to the control switches for the existing core spray valves, b.

Another source of water from the fire protection system can

'be remote manually routed from the core spray heat exchanger shell inlet to the channel outlet which supplies either of the two core spray systems.

Heat' exchanger bypassing is accomplished through a d-c motor-operated valve (M07072) actuated by remote-manual controller RMC-5529 c.

All piping and valves added fct the core spray and backup core spray systems are manufactured in accordance with appropriate sec-tions of USAS B31.1, USAS B31 7 and the ASME Draft Code for Pumps and Valves for Nuclear Service.

d. - All electrical wiring f or actuation of the backup core spray 1

' system is routed in metal conduit or raceways physically and electrically i

separate from the existing core spray system electrical system.

Electrical and instrumentation modifications have been designed to meet IEEE 279

" Proposed IEEE Criteria for Nuclear Power Plant Protection Systems."

e.

All piping sections in the enclosure spray system, spray re-L circulation system and core spray system have been missile-protected where required 'to prevent a single failure from causing total loss of function

.1 v.

11 of the affected system. Missiles considered are those originating from the high-pressure reactor system.

f.

The' backup core spray system utilizes a single spray nozzle mounted on a " bayonet". type pipe fixture extending through the center 10-inch port in the reactor vessel head. The nozzle will be centered over the core and would spray-down from about 7 fee' -bove the top of the core. Details of this. spray nozzle are shown on General Electric Draw-ings 1117C4323, 117c4594, 117C4595, 158B7986, 761E293 and 921D739 (attached).

The design and construction of the nozzle is in accordance with USAS B31.1.

A vibration analysis was performed on the core spray nozzle. The results of this analysis showed that no significant vibration will occur in the nozzle. This analysis is contained in Attachment I.

g.

A flow orifice will be installed to insure that at least one gallon per minute per bundle is delivered by the backup core spray nozzle when the system is aligned for all normal flow paths. The design of this orifice based on the criteria established by Attachment I, General Electrit i.bution to Big Rock Point Redundant Core Spray Sparger Design ano

_llation. Only one flow path exists that does not meet the one gallon per minute criteria. This is the flow path that can be established through M07072, M07069, M070TO and M07071. This flow path is considered abnormal and is not required to meet the single failure criteria established for design of the system.

It will be adminstrative1y controlled such that it will not be used except as a last resort. The orifice will be installed between FE2812 and M07070 as shown on Bechtel Drawing M-123, Rev 15 (attached).

h.

No heavily sensitized stainless steel will be incorporated into facility systems during these modifications to the core spray system and backup core spray systems.

3 Post-Incident Cooling a.

The existing post-incident cooling system consists of one automatic actuated spray, through Valve MOTO64, and a backup enclosure spre.y vnch is actuated by manual opening of a normally closed gate valve outside of the containment. The post-incident cooling system has been modified by the addition of an automatic a-c motor-operated valve (M07068) in the backup containment spray header. This new valve is automatically

i is 3

12 opened within 'five minutes of receipt of an actuation signal from one of two containment high-pressure. switches (PS-636 and PS-637 set at 2

'psig).

[=

_ The containment spray d-c operated valve (M07064) opens.

~

' and by interlock Valve:M07068 (a-c) remains closed unless the d-c valve fails to open. Vater. supply to either of the two full-capacity spray

~

systems can now be aligned from either of.the two fire system headers or from the spray recirculation system.

b.

The existing enclosure spray valve (M0706h) has been modi-fied.from a-c motor to d-c motor operated. This arrangement now insurer

~

.that one enclosure spray l system and one core spray system will remain operative in the event of either a-c or d-c power failure and tto oper-ative systems can be supplied from either the fire system or the spray recirculation system. This valve is opened autoLatically within five minutes of receipt of an actuation signal from one of two1 containment high-pressure switches (PS-7064A and PS-706hB set at 15 psig).

i

'4.

Miscellaneous Modifications-a.

Interconnection of the existing systems has required that

~ containment isolation check valves be added in the spray recirculation return line and the fire header which initially supplied only the back-up enclosure sprays. Thus, a total of two h-inch check valves were added.

b.

A flow indicator and switch for annunciation on high flow has been added to the existing core' spray system and to each enclosure spray as well as the new backup core spray system. The indicators and I

alarms are located in the main control room.

Two duplex type basket strainers (BS-5760 and BS-5761) have c.

been added to the fire protection system. These strainers are located to insure that all fire system water into the containment sprays and reactor 3

sprays does not contain solids that could plug any spray equipment.

Each strainer, including existing Strainer BS-5759, is equipped with a local

^

_ differential pressure indicator and high differential and normal alarms located in the main control room.

5 Summary of Modifications a.

Addition of a h-inch core spray header originating from the

. existing backup enclosure spray line within the containment. This line

i.

13 contains two h-inch a-c motor-operated valves (M07070 'and M070Tl) and

-one k'-inch check valve similar to_'the. existing core spray valving.

b.

Addition'of a h-inch a-c motor-operated valve (M07069) cross connecting the existing core spray line to the new core spray line.

Addition of a h-inch d-c motor-operated -valve (M07068) in c.

the exi. sting backup enclosure spray line.

. d.

' Addition of a 4-inch d-c ' motor-operated valve (M07072) cross connecting the fire system supply to the shell side of core spray heat exchanger to the_ spray recirculation line.

e.

Addition of two 4-inch containment isolation check valves in the existing backup enclosure spray line and the spray recirculation line.

f.

Addition of a bypass with a h-inch manual valve around the existing valve (M07066) in the fire system cooling water-supply line in the core spray heat exchanger.

g.

- Addition of two duplex strainers (BS-5761 and BS-5760) in the fire protection system; one in the alternate flow path off the outside fire loop, the other in the fire system supply line to the core spray.

heat exchanger with three pressure differential indicating switches s

(PDIS); one across each duplex strainer and the existing strainer, plus separate annunciators for each strainer, to indicate a plugged strainer 4

condition.

h.

Addition of. four flow indicators and high flow alarms, one in each of the two core spray lines, and one on each of the enclosure

. spray lines.

i. Addition of four reactor pressure and eight yarway level switches to control the backup core spray valves and replace the exist-ing Reactor Safeguard Post-Incident Cooling System level switches.

j. Addition of two containment high-pressure switches to con-I trol the new backup enclosure spray valve.

k.

Addition of a single spray nozzle mounted on a " bayonet" type

]

pipe fixture. This nozzle is mounted through the center lO~ inch port on the reactor vessel head.

6.

Failure Analysis The modified core spray and post-incident culing systems' failure nnalysis is.. summarized on the following Table 1:

I-(.

14 f

TABLE.

Big Rock Point Plant

- Core Spray System - Failure Analysis Component Malfunction Comments and Consequencec

' l.-

Diesel' fire pump Fails t start Electric-driven' fire pump from emergency diesel generator will-deliver required flow.

4 2.

Electric fire. pump Fails to start Diesel-driven fire pump will de-liver required flow.

i 3

Strainer BS-5759

~ Plugged Alternate flow path' to spray system from yard outside loop through Strainer BS-5761 will provide re-quired flow.

.h. Core spra'y Valve Fails to.open or Required flow is available through 4

M07051 or M07061 d-c power. failure the redundant core spray eystem.

(d-c motor operated)

5. fCore spray valve Fails to open or Required flow is availat.s through M07070 or M07071 (a-c.

a-c power failure the redundant core spray system.

motoroperated)~

6.. Containment penetra--

Sticks closed

. Required flow is available through tion check valve in the second fire supply line. or by

'either fire system the cross connection from the re-supply header circulation piping by opening M07072 manually.

7 Core spray line check Sticks closed Required flow is available through valve in'either spray the second core spray line.

system.

~

8.

Core spray ring or Plugged Either core spray system provides core spray nozzle 100% of required flow.

~

9

' Recirculation suction P. lugged Sufficient capacity is available to strainers insure adequate flow in the event that 3 of the 5 strainers become plugged.

- 10.

Core spray heat ex-Fails to open 1.

Manually operated bypass valve changer cooling water-- _ or a-c power will allow full rated flow supply Valve M07066 tailure through the core spray HX.

(a-c motor operated) 2.

Bypass around the HX (M07072) will allow required flow to enclosure spray or core spray ring directly from the fire main.

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TABLE'1

= Big Rock Point Plant Core Spray System - Failure Analysis'(Contd)

' Component

^

Malfunction ~

Comments and Consequences 11.

Cross-connecting valve. Fails.to.open on 1.

Required flow is available Ebetween fire system.

a-c power - failure through either core spray system supply Headers Mo7069-and'either containment spray (a-c motor operated).

header from the ' fire system.

2.

Required flow is available through the enclosure spray

. headers or the core spray ring from-the spray recirculation-

?

system.

12.

Valve cross connecting-. Fails to.open on-Required flowf is available through the fire system to the

-d-c power failure - the new core spray or backup en-recirculation Piping closure spray.

M07072 (d-c motor orerated) 13 Containment isolation Sticks closed Required flow is available through check valve in re--

the existing core spray or contain--

-circulation.line-ment spray headers. The spray re-circulation system is -provided with j

a test tank and piping arrangement to permit' periodic system testing.

Recirculation through the check valve during testing will insure valve operability.

lb.

Reacter level pressure Electrical Required capacity flow is available control ' circuit to failure On.cugh the second spray. system con-either core spray trolled by redundant level' pressure system switches.

15. - Cont'ainment - pressure Electrical Required capacity flow is available

' control. circuit to failure through the second spray system con-either enclosure trolled by redundant pressure spray system switches.

'16.

A-c power supply Failure D-c_ power supply available from emergency generator through in-verter.

Required flow is available through the enclosure spray and through the core spray ring.

17 D-c power supply Failure A-c power supply available from sta-tion power Transformer 11.

Required flow is available through the re-dundant core spray nozzle-and through the backup. enclosure sprays.

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Preoperational Test Procedures-

.Preoperational test procedures are being = developed to demonstrate the proper. functioning of the backup core spray system equipment additions F

- and the proper functioning of the existing core and enclosure spray systems which'have been modified asfdescribed in Section II-A above. These. test procedures shall include but not be limited to:

1.

All systems added or in which valve or piping modifications-have occurred will be flushed with water.following installation with the 9

exception of the-backup core spray nozzle and the back.up. enclosure spray system. - The backup' core spray nozzle will be flushed prior to installation.

The acceptance criteria are that the existing flush water-be~ free from par-ticulate matter ~.

2.. Hydrostatic tests will be performed on all newly installed and modified piping systems with the exception of the backup core spray nozzle Land' the backup enclosure sprays. The pressure boundary portions of the

~ backup core spray nozzle will be hydrostatically tested prior to installa-tion. Acceptance criteria are no visual leakage at a pressure equal to 2550 psi for portions of the system subject to reactor pressure, and 210 psi for systems subject to fire header pressure.

.3 All flow elements, level sensors and pressure switches will be calibrated and trip points tested prior to preoperational testing. Flow I

will be established -through basket strainers to insure flow alarms annun-

~

ciate normal flow. Differential pressure switches will be tested under these' flow conditions to insure they do not annunciate high differential i

pressure.

4.

M07069 and M07072 shall be test operated to verify the following :

Command Acceptance Criteria a.

Remote-manual open.

Valve travels from full shut to full open. Indication agrees with actual position.

I l

b.~ Remote-manual shut.

Valve travels from full open to full shut.

Irf.ication agrees with valve position.

No flow will be established during these tests.

Ip

3 17.

5. I M07051,' M07061,- M07070 and M07071 shall-be : test operated to l

verify the following:

Command Acceptance Criteria a.

Simulate low reactor-level an'd

. M07051 and' M07061 cpen; M07070 pressure ~ sensor. contact closure and MOT 071 remain shut.

4 I

to both sets of valves.

b. LMaintain signal's Step "a" and M07051 and M07061 shut; M07070

' remote manually shut M07051 and M07071 open.

Jand.M07061.

c. " Maintain' signal's Step "c" and M07051 and MOT 061 remain shut;.

remote manually shut M07070 M07070 and M07071 shut.

and M07071.

d.

' Remove signal's Step "a."

N07053, M07061, M07070 and M07071 remain shut.

e.. Block' operation of both sets

.M07051, M07061, M07070 and M07071

~

-of valves.in the control room, remain shut.

Repeat Step "a."

f.

Maintait, signal's Step "a" and M07051 and M07061 remain shut;

~

remove block signal on M07070 M07070 and M07071 open.

and M07071.

l g.

Remove signal's Step "a."

M07051 and M07061 remain shut;-

M07070 and M07071 remain open.

h.

Remote manually shut M07070 MOT 070 and M07071 shut.

t

'and M07071.

I' i.

Block operation of M07051 and M07070 and MOTO71 open after proper M07061. Repeat Step "a."

time delay; M07051 and M07061 re-main shut.

Note: During the.above testing, all position indication will be checked to verify that it indicates actual valve position. No flow will be established during these tests.

}-

6.

M0706h and M07068 shall be test operated to verify the following:

Command Acceptance Criteria a.

Simulate high-containment pres-MOT 06h opens after proper time -

sure to both valves.

delay; M07068 re=ains shut.

3 i

c.-.

-r,,

s

s k

i-18

' Command Acceptance Criteria b.

Maintain signal's Step "a"~and

- M07064 shuts; M07068-opens.

+

remote manually shut M07064.

c. -Maintain signal's Step "a"'and M07064 remains shut; M07068 shuts.

remote manually shut M07068.

d.

Remove signal's Step "a."

M07064 and M07068 remain shut.

'e.

Block operation of:M07064 and M07064 remains shut; M07068 opens repeat Step "'a. "

after proper time delay.

f.

Maintain signal's Step "a" and M07064-remains shut; M07068 shuts.

remote manually shut M07068.

l g.

. Block operation of both valves M07064 and M07068 remain closed.

- from the control room. Remove and-reinsert. signal from l

Step "a."

I h.'.

l.hintain signal's Step "a" and M07064 opens; M07068 remains shut.

remote manually open M07064.

i. Maintain' signal's " Step "a" and M07064 shuts; M07068 remains shut.

i remote manually shut M0706k.

mj.

Maintain signal's Step "a" and MOT 064 remains shut; M07068 opens.

remote manually open M07068.

Note: During the above testing, all position indication will be checked to verify that it indicates actual valve position. No flow will be established during these tests.

C.

Design, Engineering, Construction and Quality Assurance 4

1.

Design The modifications discussed in Section A resulted from the new criteria requiring that safety related systems be designed with re-j

'dundancy with respect to single failure criteria for active components.

The design. concept has been to provide an automatic backup core spray system that will withstand a six-inch vessel jump accident and is redun-dant to, the original core spray system. The backup enclosure spray sys-l

-tem has been modified to allow automatic and remote-manual operation instead of manual operation. In addition, two piping cross connections controlled by remote manually operated valves and two basket strainers

.have been incorporsted in the design to provide added flexibility and

= - -

m m

T

-e

'--+--

-wr

'-w

- w

-(-

r 19 reliability. Thes'e changes to the core spray, backup core spray, enclosure spray and-backup enclosure spray ' system are further described in Section II-A' and Bechtel Drawing M-123, Rev 15 2.

Engineering The General Electric Company designed the backup core spray sparger a'nd' supplied flow-data required to insure proper. system design to insure adequate core cooling. The _ Bechtel Corporation provided engineering and pro-curement services for all modifications with the exception of the backup core The efforts of these two_ companies were reviewed and moni-spray sparger.

tored by' Consumers Power Company personnel.

- 3 construction 1The Bechtel Corocration has been engaged as thes contractor for the construction portion of these modifications.

During the February-March 1970 refueling outage, modifications affecting the low-pressure portions of the systems were installed. During the February 1971 refueling-outage, the remainder of the piping modifications will be installed, the backup core spray sparger installed and electrical and instrumentation wiring connected.

The backup core spray sparger is being fabricated by the General Electric Company.

4.

Quality Assurance Quality. control and quality assurance requirements were - specified -

in the mechanical bid specifications. These requirements in general-covered radiography, magnetic particle testing, materials certification, hydro-

]

static testing, cleaning, shipping and welding procedures.

Bechtel Cor-poration was engaged to insure that vendors met the requirements of the specifications. The electrical cable installed was tested in a timed water immersion high-voltage and insulation-resistance tests. In addition, each type of cable is certified to be of a construction that passes a ver-tical flame-resisting-test in accordance with IPCEA S-61-402, Part 6.5 During construction activitiec in February and March 1970, the contractor implemented a quality assurance program as follows :

a.

Piping and Valves (1) Receiving Reports - Prepsred for materials requiring QA documentation.

(2) Final Inspection Report - Prepared upon completion of pipeline installation.

k 4

20 t

(3) Hydrostatic Test Reports b.

Welding (1)~ Receiving Report - Prepared for welding rod.

(2) Field Weld Checkoff List - Prepared for each field weld.

(3) Filler Metal Withdrawal Authorizations - Prepared for each field weld.

(4) P; ping Inspection Record - Prepared for each iso-actric drawing and showing the complete record for each field weld.

(5) Installed Inspection Report - Prepared for each line.

In addition to the above, welder performance qualification te 't records and material certifications for welding rod were obtained.

Consumers Power Company developed a program to monitor construc-tion. This program was used to monitor welding, electrical, site.

s.

age and housekeeping and radiography construction activities.

Audios were made of the contractors quality assurance in each activity.

Documentation covering the manufacture and testing of procured materiala, and construction activities were obtained and are filed.

A similar program will be conducted during the remainder of construction activities in February 1971.

III. Hazard's Considerations Based upon the above description and systems' comparison, the following conclusions may be drawn:

1.

Operation and control of the original core spray system will remain essentially as it was originally installed.

2.

The backup core spray system is redundant to the original core spray with respect to single failure criteria and will operate to prevent fuel-clad melting in the event of a failure in the original core spray system.

3 The backup core spray system is designed to withstand a six-inch _

vessel jump.

4.

The single core spray recirculation line has been missile shielded to provide added reliability.

l

m, 7-t 21 '-

l

.5.

The backu'p containment spray system has been modified

- to' provide for automatic or remote-manual operation in the event of a failure in the~ containment spray system.

26..No heavily sensitized stainless steel components will be

installed within the primary coolant system pressure

. boundaries as a result of these modifications.

7 Instrumentation and alarms have been added to the post-incident. cooling systems to provide' the operator with

-more system status in.ormation.

' Based upon' the above considerations, we have concluded that the

. use of these modified post-incident cooling systems do not present a sig-

~

nificant change.in the hazard's considerations described or implicit in the Final Hazards Summary Report.

CONSUMERS POWER COMPAhT By Senior Vice President Date: February 2,1971 Sworn and subscribed to before me this second day of February 1971.

O.

vas.. O amu h i Notary Public, Jackson County, Michigan My commission expires January 15, 1972 i

4