ML20205Q905

From kanterella
Revision as of 18:00, 6 December 2021 by StriderTol (talk | contribs) (StriderTol Bot change)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
Forwards Response to NRC Request for Info Re Status of Reg Guide 1.97 Implementation.Util Intends to Provide Category 3 Containment Temp Indication as Originally Committed in
ML20205Q905
Person / Time
Site: Rancho Seco
Issue date: 03/30/1987
From: Julie Ward
SACRAMENTO MUNICIPAL UTILITY DISTRICT
To: Miraglia F
Office of Nuclear Reactor Regulation
References
RTR-REGGD-01.097, RTR-REGGD-1.097 JEW-87-455, NUDOCS 8704060109
Download: ML20205Q905 (19)


Text

r

$SMUD SACRAMENTO MUNICIPAL UTluTY DISTRICT C P. O. Box 15r330, Sacramento CA 95852-1830,(916) 452 3211 AN ELECTRIC SYSTEM SERVING THE HEART OF CALIFORNIA JEW 87-455 March 30,1987 Director of Nuclear Reactor Regulation Attention: Frank J. Miraglia, Jr.

Division of PWR Licensing-B U S Nuclear Regulatory Commission Washington D C 20555 Docket 50-312 Rancho Seco Nuclear Generating Station Unit #1 REGULATORY GUIDE 1.97 IMPLEMENTATION STATUS

Dear Mr. Miraglia:

As requested by the Rancho Seco Project Manager, the District has reviewed the status of Regulatory Guide 1.97 implementation. In preparing this status report a review of the previous documentation was performed and resulted in the chronological listing found as Attachment 1 to this submittal. Retracing these documents reveals that the District's September 14, 1984 letter provided the dates for each of the twelve items which, at that point in time, had not yet been installed. The scheduled completion dates were determined using the District's Living Schedule. All of the original 12 open items have been, or will be, implemented prior to restart of the unit with the exception of the coolant inventory variable (14). As noted on Attachment 2 this represents an acceleration of the original schedule on several of these items.

On August 19, 1985 the staff provided an interim report on the District's .

Regulatory Guide 1.97 positions and requested additional information on eleven variables. The letters which followed this request provided additional justification as well as committing to install or upgrade several additional variables listed in Attachment 2 (6, 35, 47, 57, 62A, 45). The implementation of these new variables was scheduled as noted in Attachment 2 and all but one were subsequently accelerated per the staff's request. This brief outline and l the chronology provided in Attachment 1 provides indication that the District has been responsive, timely and cooperative with the staff in resolving the Regulatory Guide 1.97 issue. The implementation schedules provided in Attachment 2 are based on current priorities and the resources available for implementation. Therefore, the District considers the schedule described in Attachment 2 to be reasonable and acceptable for implementation of the remaining Regulatory Guide 1.97 variables.

8704060109 870330 g PDR ADOCK0500g2 P  ;

8lt DISTRICT HEADQUARTERS O 6201 S Street, Sacramento CA 95817-1899 m

s

. Frank J. Miraglia, Jr. March 30,1987 JEW 87-455 The staff also requested justification for interim operation without each of the variables currently scheduled for Cycle 8. Attachment 3 provides the information for each of these variables as requested.

During the performance of this review the District discovered the staff has accepted a Category 3 containment temperature monitor (SMUD Variable #57) on another Docket. A review of the particulars in that case, provided as Attachment 4, has indicated that the staff's acceptance is equally applicable to the District. Based on this review and the recent staff decision, the District intends to provide Category 3 containment temperature indication as originally committed in our July 13, 1984 letter.

Attachment 5 contains revision 4 to the District's Regulatory Guide 1.97 position paper originally submitted to the staff on September 14, 1984. The changes are mostly typographical with the exception of the changes to variables 26 and 17. These changes delete tag numbers of instruments which are non-qualified backups to the listed instruments. In addition, the change made to variable 55 provides consistency with the information in Attachment 4.

If there are any questions contact John Atwell of my staff.

Sincerely, f

ohn E. Ward Deputy General Manager, ear j Attachment cc: George Kalman, NRC - Bethesda A. D'Angelo, NRC - Rancho Seco I

I I

/

ATTACHMENT 1 REG. GUIDE 1.97 CHRONOLOGY i-The following provides a short history of ,the District's response to Regulatory Guide 1.97.

  • July 13, 1984 - Letter transmitting SMUD's original Regulatory Guide.
. 1.97 positions.

,

  • September 14, 1984 - District transmittal of the revised Reg. Guide 1.97 paper incorporating the description of SPDS.
  • July 9, 1985 - SMUD provided a listing of Reg. Guide items which had

! not been completed and the schedules.

  • August 19, 1985 - NRC interim report on Reg. Guide 1.97 plus 11 requests for additional information.
  • September 30, 1985 - The Dis.trict provided a detailed discussion of

, each item listed in the July 1985 letter.

  • October 31, 1985 - SMUD.provided the responses to the questions from the NRC August 1985 letter.

.

  • January 13, 1986 - SMUD provides additional information on the pressurizer level and heater current variables.
  • November 12, 1986 - The District provides an updated status of the items not yet installed with accelerated implementation dates for all but 2 items. Dates were changed as a result of a meeting held with

] the staff on August 14, 1986.

I i

i 1

i i

ATTACHMENT 2 , ,

MTE OF ORIGINAL VARIABLE VARIABLE COMMITNENT COMITMENT NEW NUISER* UPGRADE TO: LETTER DATE DATE ORIGINAL 14 Coolant Inventory (ICC) New 9/14/84 Cycle 8 Cycle 8 OPEN Variable (No Change)

ITEMi (Cat 1) +

4 Steam Generator Cat 1 9/14/84 Cycle.9 Restart 87 Level 5 Steam Generator Pressure Cat 1 9/14/84 , Cycle 9 Restart 87 1 RCS Hot Le'g Temperature Cat 1 9/14/84 Cycle 8 Restart 87 44 Pressurizer Level Cat 1 9/14/84 Cycle 9 Restart 87 Density Compensation N/A SPDS Upgrade Cat 1 9/14/84. Cycle 9 Restart 87 (Class 1 redundant indication)

NEW E Neutron Flux Cat 1 10/31/85 Cycle 9 Cycle 8 C0lGETMENTS MADE AFTER 35 RHR (Decay Heat) Heat Cat 2 10/31/85 Cycle 9 Cycle 8 4 NRC LETTER Exchanger Outlet (8/19/85) 47 Quench Tank (PRT) Temperature Low Range 10/31/85 Cycle 8 Cycle 8 (Remains (No Change)

Cat 3) 57 Containment Atmosphere Cat 2 10/31/85 Cycle 9 N/A Temperature (See Attachment 4). ,

l 62A Component cooling Water Cat 2 10/31/85 Cycle 9 Cycle 8 Temperature to ESF System (NSCW) 45 Pressurizer Heater Status Direct 1/13/86 Cycle.9 Cycle 8 Indication l (Remains Cat 3)

O As identified.in the District's October _31 1985 g and September 149 .198_4 - submittals.

3, 7 . , - . ,

y,. N i'I ] _e Y# . , , b 'P~ '

}' y g  %  ;

- l x 's a l

[ t j \,f, et .

r p'

. ATTACHMENT 3 4 P

y n r .y.

s t s.: v 6N Variable Jame: Coolant Inventory /Reect'or Vessel Level (14) g 4 4

Category / Variable Type
Category 1/ Type 3 Y w s, ..

% > t

' Variable Purpose (R.G. 1.97):- Provide information to indicate whether plant \'

safety functions are being accomplished.- (Veriff. cation; accomplishment of ,Q'J' mitigation). [' ,

i

. I c , y e,1 Justification until Cycle 8: The purpose of this variable.is the verification .. c 'g ,;

that cooling water is reacliing the core. This verification can be ok,tained~

  • Q' 's "

via alternate means, direct as well as indirect, currently eva11able. The ,' ,

operator,.viaSPDS,hasavailableCategory1 variables (bot 1eptemperatpedl/W! '

hot leg level, core exit tseperature RCS pressure, pressMfgerilevel) which ')f will provide indication that adequate . cooling is being prov;de? in the cms.' r s ,

In additi6n, Category 2 subcooling margin curves are available'['.SP?S) asj W11 as Class 1 indication of Tsat and Psat in the control room. This}$.emperakure and pressure Indication anMthe flow monitoring (Category 2) of thh Lecay'f' Heat, high pressure and low iressure injection systems (SPDS) wil11 provide the W be-operator sufficient'ini%rmation to determine that, thCcore is being provide.4 t ' s adequate' cooling. Since the intended function is\ me via other variables; % /

operation during the interkperiod is cons *dered ach'tytable. ..

,s h

~

) i  %

  • ; * ? .

N e

{ y 7_ .

g7 , s s

\. \ l

  • g, s< V,.

s

' _ i- '4 s

[ \

o

,7 s

st<t. s ., t / 3 ,

y o

, p. j u

/ ,'y /

~'

l, Q.

y ' i. , l

3s j 'y, j s  ; 'ti >

s s J. /

4 l y s o. s ) c

4 -t sy, t s

5

, j

~. q, s\.s 11- s

(

3 c 1 J. \'

, l' .s - U s( '\, * . ), ,

b I,4

,. g

. .. i.

i

'v k' '

4 s p m

b' s . ,'., ,

N _,

s; 'y Q. c, \'  ; l ? W; qe[: .y y c . _ s 1 -

,1

< s t

. t 3 s, p I

I

\ s 4 Qt -(

( ,. o , m ..,( ,. - 5 - f 3

k '" .

s, \ 1, 4,

f U

,. v .

g' ')~ .

V sf*

) . , ,* ( c s

r ,

'y

~

{'

l 'lg ^~

t  ?, , ,,

h $ h f .. r i i, \' ,5 - /y' [N_ ,

e. -

i- (

('*_' f' j ,

)

i \ s t 'k< ' 5. c i

'S 1 , ','

N /  %

fr T. er ,

lg - .' mv..,e. .,

-3

4 "{ 7 Gy , 'i. . [ .
s

. * % ,_ _ J __

h L-L - . J . L; _ , , - . 't; _] m

3:,

~ '

ATTACHMENT 3 (CONT.)

4 < 1.Va iable Name: ~ Neutron Flux (6)

Cetegory/ Variable Type: Category 1/ Type B J' ,!

Variable Purpose (R.G. 1.97): Provide information to include whether plant s'afety Junctions are being accomplished. (Function detection; accomplishment l

of mitigation).

Justification until Cycle 8: In determining the amount of reactivity. control available to the core several methods already exist. The plant currently has excore neutron flux instrumentation, control rod position indication and boron I concentration neasurement capability via the normal and Post Accident Sampling System which could provide indication of the reactivity levels in'the core.

i s During post-accident conditions additional means of reactivity indication is available by the use of the Borated Water Storage Tank level (Category 3),

containment sump level (Category 1) and safety injection flow indication (Category 2). Thus the operator will have adequate indication during the

'interim operation period to determine that adequate reactivity control is available to the core.

{

v L

2 4  %~ s b 1 -

),

i v

[ ':k,r

.e/

    • \ '

'i; t  :

i N 's

~s.' ' *

( s A 5;N_.'- -

. ;. , .,, 7 l. +

J l s t

I t '

lg 0 ,

s\

i.

c m. -) .,. --.,

A 3$ l

. .t l

,  : y i

\

,, ATTACHMENT 3 (CONT.)

Variable Name: RHR (Decay Heat) Heat Exchanger Outlet (35) >

gi

.1 x

-J Category / Variable Type: Category 2/ Type D 1

. D.

q t-Variable Purpose (R.G. 1.97): Provide'information to indicate the c'peration 3 of individual safety systems and other systems important to safety. -(To 1

~

monitor operation and for analysis.) - '- '

4 Justification until Cycle 8: Proper operation of the Decay Heat Removal (DHR) .'

System can be obtained from information currently available to the operator. - c The combination of the Category 3 heat exchanger outlet temperature indication

, & Category 2 ficw indication will provide the operator indication of proper ,

DHR system operationn Alternate /means are also available'using the DHR suction temperature and Nuclear-Service Cooling water differential.

temperature. . Thus adequate information is available to the operator to verify proper DHR operation during the interim period of operation.

c.

a s t

4 .(

t  !

' N 3

t 7j i y

l j i i

& s / k i.

s ,

r, s t

< V: _ -i _ . 1

  • y} -,)

r 9 .

's

  • i i I

i t .y l s

)

i i I~ .i '

1 ', ,

f 6 s  :

at.  ! tl

..  ! ~

N!. , ,, - -.

J ti

'2 A, '

.g4

).ji ,

i [ .O 1 ATTACHMENT 3 (CONT.)

'g.

Variable Name: Quench. Tank (PRT) Temperature (47)

,y +

[ Category / Variable Type:- Category 3/ Type D Variable Pur' pose (R.G.'1.97): Provide information to indicate the operation of individual safety systems and other systems important to safety. (To

, monitor operation).

O

. Justificat3on until Cycle _8
The PRT temperature indication currently

-installed on the auction of the PRT recirculation pump has been determined to be acceptable (NRC letter dated 8/19/85) for temperature indication for this variable. The modification required to provide full compliance is the lowering of the temperature range from 1000 to 500F. Since post-accident water / steam temperatures anticipated to be relieved to the PRT would be at

. temperatures greater than 1000F, interim operation without the extended range will not be affected.

o I

\

t 4

f wr- ,-

yl w- -we.- i - --. , , -

s - - - - ./ y +---g .

-wge. p. - we - i

a ATTACHMENT 3 (CONT.)

Variable Name: Component Cooling Water Temperature to ESF System (NSCW) (62A)

~

Category / Variable Type: Category 2/ Type D Variable Purpose (R.G. 1.97): Provide information to indicate the operation of individual safety systems and other systems important to safety. (To monitor operation).

Justification until Cycle 8: Proper operation of the NSCW can be determined by the use of the Class 1 pump and valve status indication. With indication of proper system alignment and the pond providing an assured source of sufficiently low temperature coolant the operator will have adequate

'information of proper system function. In addition, Category 3 NSCW temperature indication is provided which gives direct indication that heat removal by the NSCW is occurring. Thus adequate indication is available to the operator to determine proper operation of the NSCW system.

i i

l l

l l

-l l

ATTACHMENT 3 (CONT.)

Variable Name: Pressurizer Heater Status (45)

Category / Variable Type: Category.2/ Type D Variable Purpose (R.G. 1.97): Provide information to indicate the operation of individual safety systems and other systems important to safety. (To determine operating status.)

l Justification until Cycle 8: The control.of the pressurizer heater bank is i either "on" or "off" and not by modulation of the current. Thus the existing I

heater status lights will provide the operator with the state of the heaters.

The effectiveness of the heaters can be determined by the use of the Category 1 RCS pressure and pressurizer level indications available via SPDS.

Consequently the operator has available indications which will provide a .

status of the operation of the heaters during the interim period.

i i

i y.<

--ra- --

r-w- , w , .-e, -

1 l

l 1

4

.- ATTACHMENT 4 l l

CONTAINMENT ATMOSPHERE TEMPERATURE The District has reviewed its position on variable no. 57 in light of the recent acceptance of Category 3 indication for this variable by the staff on the South Texas Project (Docket l's 50-498 & 499, SSER-2). A review of-the position taken by HL&P reveals that the indication available to the operator at Rancho Seco is comparable.

The key variables for controlling the containment building environment are radiation, hydrogen concentration and containment pressure. All of these variables have been-provided by the District as Category 1 variables. -As stated in the original District position on Regulatory Guide 1.97 (July 13, 1984) the primary variable required to show accident mitigation and.

containment integrity is containment pressure. The temperature indication is only a backup to containment pressure. This is based on the post-accident containment atmosphere pressure and temperature being coupled due to the -

i 3

saturated conditions which would exist af ter containment spray initiation.

Therefore the post-accident containment temperature could be obtained based on the saturated containment pressure. This will provide a better indication of the general containment temperature rather than a localized temperature that

).

would be provided by' individual temperature elements.

j i To assure containment cooling is being provided, the operator has several

, indicators available. As an indicator of cooling provided by the containment spray systet instrumentation is provided for pump status (Category 2), Class 1 valve position, spray flow, spray water temperature, and containment sump

] water level (Category 1) all of which are available to the operator..

Containment cooling provided by the Reactor Building Emergency Cooling System is indicated by Class 1 fan status as well as pump and valve status for the Nuclear Service Cooling Water System.

Based on this information and the indication available to the operator, l

^

containment temperature is considered a back-up to containment pressure. As a l result of the staff's review on South Texas and the information provided here the District feels justified in providing containment temperature as a l Category 3 variable as originally presented to the staff in the District's July 13,1984 submittal.

l l

l l

4 ATTACHMENT 5 REVISION TO REGULATORY GUIDE 1.97 POSITION PAPER 1

l l

i I

Var. Variable Per SED SRD Compiter MC sin n). R.G. 1.97 Rev. 3 Tag Nr>a. Cat. Display hoge hnge Commenta l

HPE B VEN'.TTS corit!d.

16 ICS Pressure IT-21050 1 SIDS 0-3000 pelg Comply Same as Varlable 2 (category 1) IT-21051 IDADS i

17 Containment IE-26112 C,D 2 SIDS Top to Botton Comply See Variable 3 Sine Eter Tavel IDADS Plant See M>te I (Category 2) New 12-20509 A,B 1 Slecific 17 (category 1) Wide IE-20510 A,B i

18 -Containment IT-53621 1 SIUS 0-design Comply

, Pressure IT-53622 IDADS Pressure (Category 1) (59 poig) 19 Cont. Tao. Valve See 1 Sms Closed / Open/

Iba (excl. Table IDADS Not Closed Closed Check valves) 5.2-2 See n>te (Category 1) in IISAR 19 20 Containment IT-53621 1 SmS -5 peig Couply Same as Wriable 18 Pressure IT-53622 IDADS to dealgn (Category 11 preamire (59 pelg)

+

e la aey.4 k

e

, . e.

l Var. Variable Per SBlUD Sti1D Contuter URC SMUD l 110 R.G. 1.97 Rev. 3 Tag ibs. Cat. Display Range Ramje Cor.nia:nts

'ivpg c trARTARLF9 21 Core Exit See Variable 1 SPDS 200 to Conply Living Schedule ~

Teg erature 13 TDADS 23000P Sanc as Variable 13 (Category 1) l ~22 Radioactivity Hone M/A 1/2 Tech N/A See Variable 23 l Concentration See Spec to 100 (Category 1) Note x Toch spec 22 ,

l 23 Analynis of Pass 3 10-6 to 10-6 to l Prinary Coolant 10 Ci/ml 3.75Ci/ml (Category 31 See Note 23 1

24 RCS Pressure (Category 1)

PT-21050 IT-21051 1 SPDS IDADS 0-3000 psig Conply' Sane as Variable 2 d 25 _Containnent IT-53621 1 SPDS. -5 psig'to Conply Sane as Var f able 18 Pressure PT-53622 IDADS 3 x design (Category 1) (177 tsig)

Containnr:nt LE-26112 C,n 26 Sune Ititer Level 2 SmS

IDADS

'Ibp to

. Bottom conply See Ibte Sann as variable 17 g (Category 2) Urs LC-20'iO9 A,B -1 Plant 17-(Category 1) Wiele LE-20510 A,B Specific 19 Rev.' 4 '

. o.

I I Var. Variable Per 9tD StD Compiter PRC stb No. R.G. 1.97 Rev. 3 Tag the. Cat. Display Range Range Conse:nts l; - _

TYl%.Il_YMIflRfFS Cor1L'd, -

f 39 Flow in IIPI ET-23805 2 SIDS 0-1104 Comply i System ET-23806 IDADS design flow

{

(Category 2) ET-23807 (300 gpn) i EP-23808

, l 40 Plow in IPI FT-26003 2 SEDS 0-1106 Comply r

System ET-26004 IDADS dealgn flow

(category 2) (3000 gpn) g i

i ,

' livDS 41 Refueling E ter  !!P-25001 3 ibp to Comply i Storage tank Imvel LI-25008 See Dottosa

! (Category 2) tbte (0-50')

41 i

42 Reactor Coolant Panels 3 Motor Comply l Fung Status If2PS, 32, Ostrent- (Motor (category 3) 33, 34, 35 Ostrent) 43 Prim. Sys. Safety XE-21520 2 IDADS Closed / Open/mt f.1ving Sciudsle

.Re1fef VaIve Pos. XE-21521 Wt Closed Ot en See (Category 2) XE-21522 Note 43 XE-21523 i XE-21524 .

XE-21525 44 Pressurizer T.7-21503A 1 - Sins Top to 0-320" f.iving Scludsle Icvel I.T-215038 IDADS Bottosa See >bte (Category 1)  !?P-21503C .

(0-503") 44 1

22 Rev. 4

- _ - . _ _- __. .- =_ _- - _.

I f Var. Variable Per fMD SMID Compiter M4C SMID 2

M1 R.G. 1.97 Rev. 3 Tag tes. Cat. Display hnge Enge Comments -

TYPE E VARTABIFS

~

68 Containment R-15049 1 SHIS 1 to 107 Comply Same as Variable 27 I

Area bdiation R-15050 IDADS R/hr

(Category 1) Diets i

69 Radiation R-15025 3 10-1 to Comply Estouure Rate R-15030 104 R/hr (category 3) thru' 38 Ibrtable Analyzers 70 Containment or WA WA 10-6 to WA ' Same as Variable 32 lbrge Effluent See 105u C1/cc (Category 2) mte 0-110% vent 32 design flow 71 Reactor Shield WA WA 10-6 to WA mt in Rancio Bldg. Annulus N)t In 104u C1/cc Seco Design (If in Design) Deal

te 0-110% vent

72 design flow 73 Condenser Air WA WA 10-6 to WA See Variables Rem. Sys. Exhaust (Category 2)

See mte 105 u Ci/cc 0-110% vent 28 and 72 k 73 design flow 9 27 Rev. 6 e - .- - m I Var. Variable Per Ste p fMD Coopster DEC SBED Pb. R.G.1.97 Ih:v. 3 Tag tha. Cat. Display Range Hange cw ta 3YPE E VARIABfIN C6, 74 Common Plant WA WA 10-6 to WA See variables vent See 10h Ci/cc 32 asul 72 ' Category 2) R>te 0-110% went 74 design flow 75 Vent from Steam R-15047 WA IDADS 10-1 to Comply

Cen., Safety R-15048 See I*stS 103u C1/cc Rel. Valves M>te seconds 75 masa (Category 21 76 All Other~ WA WA 10-6 to WA See Variables
in Release Ibinta See 102u Ci/cc 34, 35, 74, 77, 79 (Category 2) M>te 0-1104 vent 76 design flow 77 All ID Plant R-15001 A,B,E 3 IDADS 10-3 to See Ibtes See varJables l Release Points R-15002 A,B IWptS 102u C1/cc 32 and 75 28, 32, 33, 72 , 75 d l (Category 3) R-15004 0-110% went l R-15017 A,B design flow

! R-15044 k-15045 l R-150046A k-15047 l R-15048 re-15050 PP-54206 t1t-95108 tT-54612 FI-24211 78 Alttw>rne Portable 3 - 10-9 to Comply Radiohalogens & Analyzers

  • 10-3u C1/cc Particulates j (category 3)

- 28 new. 4 .. - . . . . . = - .- . - ~ 47mriable Exe11 nation . 72 These Radiation Monitors were installed to meet'the requirements of NUREG 073 7, Clarification -II.F.1, ~ Attachment 1, and as such, the Reg. Guide 1.97 Category classification is not applicable (accepted by the NRC in the letter dated 5/1/80, Reid to Mattimoe). 73 The condenser air jet ejector discharge is vented through1the Auxiliary Building common stack (variable 72). Therefore, this variable is not applicable as a post accident monitored i variable. In addition, the condenser air removal system is monitored by a Category 3 Type E system (see variable 281 jpg i j 74 The. Common Plant Vent is the Auxilliary Building vent  ! 4 (variable 72) and, therefore, this variable is not } applicable. The containment purge discharges through  :

dedicated vents. However, the Reactor Building purge fans are tripped off on a high radiation signal of approximately 10-8 micro Ci/cc for the particulate monitor or 10-4 micro Ci/cc for the gas monitor (variable 32, Containment Effluent
Radiation).

4 2 75 Externally mounted radiation monitors were installed to provide combined noble gas effluent monitoring for the Steam Generator Safety-Relief Valves and Atmospheric Dump Valves (ADV) meeting the requirements of NUREG 0737, Clarification

Item II.F.1, Attachment 1 and, as such, the Reg. Guide 1.97 category classification is not applicable (accepted by the l NRC in the letter dated 5/1/80, Reid to Mattimoe) .
These radiation monitors, along with the Steam Generator j Safety valve and Aqv position indications (acoustic leak i detection system), and the plant computer which monitors the i number and duration of valves actuated, provide the necessary input for calculation of release rates per unit time as j '

i . required by NUREG 0737, Clarification II.F.1, Attachment 1. 1 (This is consistent with the B&WOG Reg. Guide 1.97 task . force's generic position.) ' 4 other variables which may be used to refine the calculation 3_ are steam Generator Pressure (Category 1, variables 2,12, i 16, 24, and 29) I 76 Effluents are discharged through other monitored plant vents , (see variables 3 2, 33, 72, 75, and 77) . Therefore, this variable is not applicable. ! i 1 i ! l 4 i \ 4 ! 41 Rev. 4 l - 1 p ,a Variable . Explanation: 55 All RB spray piping is Rancho'Seco-QA Class 1 and seismic-category 1. All piping inside the.RB is designed to ANSI B31.1. All remaining piping and connections to the spray system are in accordance with ANSI B31.7. The controls for the pumps and all valves which are not~1ocked open are Class 1 with indication in the main control room. The District has performed single failure analysis on all active components of the RB spray system to show that the failure of any single active component will not prevent the fulfilling of the design function following a LOCA. Each train of the RB spray system also includes a non-qualified flow transmitter which provides indication in the Control Room. The primary indication of the adequacy of the containment cooling systems are building pressure and temperature. At Rancho Seco RB pressure is Category 1 and RB temperat'ure Category 3. The Class 1 pump and valve control monitors indicate RB spray system actuation. In conclusion, the District maintains that indication of RB spray flow is a backup variable and therfore should be Category 3. 38A Rev. 4-L__.___.__ _____.__.________________._._____._____.________.____________.__.________._._____._________.__________.__.__._______________J -