ML20097D927

From kanterella
Jump to navigation Jump to search
Proposed Tech Specs Re Scram Discharge Vol & Control Rod Operability
ML20097D927
Person / Time
Site: LaSalle  Constellation icon.png
Issue date: 06/02/1992
From:
COMMONWEALTH EDISON CO.
To:
Shared Package
ML20097D918 List:
References
NUDOCS 9206110203
Download: ML20097D927 (23)
v • d • e


Text

.

k ATTACHMENT B Proposed changes to Appendix A, Technical Specifications of Facility Operating Licenses NPF-11 and NPF-18.

NPF-11 NPF-16 3/4 1-3* 3/4 1-3*

3/41-4" 3/41-4" 3/4 1 -5*" 3/415"*

  • This page has been included for information only. No changes have been made.

"This page was revised in the Reference (a) submittal, and has been included for information only.

"'This page was revised in the Reference (a) submittal, and is being further revised in this supplemental submittal. All proposed changes to this page are shown.

9206110203 920602 PDR ADOCK 05000373 P PDR ZNLD/1847/7

~rr

, ho lChany 5vy\

.% for mdtion C4 I N REACTIVITY CONTROL SYSTEM

~

G^-

~

3/4.1.3 CONTROL RODS CONTROL ROD OPERABILITY LIMITIN.G CONDITION FOR OPERATION .

3.1.3.1 All control rods shall be OPERABLE.

APPLICABILITY: OPERATIONAL CONDITIONS 1 and 2.

ACTION:

a. With one control rod inoperable due to being immovable, as a result of excessive friction or mechanical interference, or known to be untrippable:
1. Within 1 hour: l a) Verify that the inoperable control rod -if withdrawn, is-separated from all other inoperable control rods by-at-least two control cells in all directions, -

b)- Disarm the associated directional control valves

  • either:- _j.
1) Electrically, or-2)- Hydraulically _by_ closing the drive water and exhaust water isolation valves.

c) Comply with Surveillance Requirement 4.1.1.c,

, 2. Otherwise, be in at least HOT SHdTDOWN within the next 12 -hours.

3. Restore the ir.opsrable control rod to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or 5e in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
b. With one or more control rods trippable but inoperable for causes other than addressed in ACTION a,- above:--
1. If the inoperable l control rod (s) is withdrawn:

a) Immediately verify:

1) That the inoperable withdrawn control rod (s) is separated l_

from all- other inoperable withdrawn control rod (s): by at -

least two control cells in all directions, and

2) Thel insertion capability of the Linoperable withdrawn control rod (s) by. inserting the control rod (s) at least one notch by drive water pressure within the normal-operating range **. l b)- Otherwise, insert the-inoperable withdrawn control rod (s) and disarm the associated directional control valves
  • either:- l
1) -Electrically, or 2)- -Hydraulically by closing the' drive-. water and exhaust-water
  • olation valves

'*May be rearmed intermittently, under administrative control, to permit testing

(

~ /- l associated with restoring the control rod to OPERABLE status.

    • The inoperable control . rod may then be withdrawn to a position no further l withdrawn than its position when found. to be inoperable.

LA SALLE - UNIT 1 3/4 1-3 - Amendment No.18

\

i REACTIVITY CONTROL SYSTEM LIMITING CONDITION FOR OPERATION (Continued)

ACTION (Continued)

2. If the inoperable control rod (s) is inserted: -

a) Within 1 nour disarm the associated directional control ltg valves

  • either:
1) Electrically, or
2) Hydraulically by closing the drive water and exhaust water isolation valves.

b) Otherwise, be in at least HOT SHUTDOWN within the next 7

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

37ngg7t A ) 3. The provisions of Specification 3.0.4 are not applicable. lis

'-> #~

c. With more than 8 control rods inoperable, be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, k 2,,

SURVEILLANCE REQUIREMENTS

(

4.1.3.1.1 The scram discharge volume drain and vent valves shall be demonstrated OPERABLE by:

a. At least once per 31 days verifying each valve to be open**, and lio
b. At least once per 92 days cycling each valve through at least one complete cycle of full travel.

4.1.3.1.2 When above the low power setpoint of the RWM and RSCS, all withdrawn control rods not required to have their directional control valves disarmed electrically or hydraulically shall be demonstrated OPERABLE by moving each control rod at least one notch:

a. At least once per 7 day;, and
b. At least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when any control rod is immovable as a result of excessive friction or mechanical interference.

4.1.3.1.3 All control rods shall be demonstrated OPERABLE by performance of Surveillance Requirements 4.1.3.2, 4.1.3.4, 4.1.3.5, 4.1.3.6 and 4.1.3.7.

  • May be rearmed intermittently, under administrative control, to permit testing l 18

( associated with restoring the control rod to OPERABLE status.

    • These valves may be closed intermittently for testing under administrative j is control.

LA SALLE - UNIT 1 3/4 1-4 Amendment No. 18

REACTIVITY CONTROL SYSTEM SURVEILLANCE REQUIREMENTS (Continued) 4.1.3.1.4 The scram discharge volume shall be determined OPERABLE by '

demonstrating]~

Q _s N

a., ,The scram _ discharge volume drain aiid . vent valves APE _RABLy, when ~

l b.ontrol ion of lessrods than are or scram equal totested 50% ROD from a normal DENSITY at least control oncerod per configura-18TonthTp9~verifyingthatthe'drainandventvalves: l J '1. Close within 30 seconds af ter receipt of a signal for control rods to scram, and

', 2. Open after the scram signal is reset.

l __

r

b. Proper float response t,y performance of a CHANNEL FUNCTIONAL TEST C of the scram discharge volume scram and control rod block level (y instrumentation after each scram from a pressurized condition.

(

~

" ~ ~ ~ ~ 'N__

/',*The provisions of Specification 4.0.4 are not applicable for entry into ' A OPERATIONAL CONDITION 2 provided the surveillance is performed within

_2 hours after achieving _less than or.. equal to 50% ROD DENSITY.

LA SALLE - UNIT 1 3/4 1-5 Amendment No. 18

% Choq/5 %h REACTIVITY CONTROL SYSTEM T/4.1. 3 CONTROL RODS ((To 4g h t - uw ,d Ca k )

CONTROL R00 OPERABILITY LIMITING CONDITION FOR OPERATION E 1,3.1 All control rods shall be OPERABLE.

APPLICABILITY: OPERATIONAL CONDITIONS 1, and 2. l ACTION:

a. With one control rod inoperable due to being immovable, as a result of excessive friction or mechanical interference, or known to be untrippable:
1. Within 1 hour:

a) Verify that the inoperable control rod, if withdrawn, is separated from all other inoperable control rods by at least two control cells in all directions.

b) Disarm the associated directional control valves

  • either:  ;
1) Electrically, or
2) Hydraulically by closing the drive water and exhaust water isolation valves. -

c) Comply with Surveillance Requirement 4.1.1.c.

} 2. Otherwise, be in at least HOT SHUTOOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

3. Restore the inoperable control rod to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT SHUTOOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

( b. With one or more control rods trippable but inoperable for causes other than addressed in ACTION a, above:

1. If the inoperable control rod (s) is withdrawn:

a) Immediately verify:

1) That the inoperable withdrawn control rod (s) is separated from all other inoperable withdrawn control rod (s) by at least two control cells in all directions, and
2) The insertion capability of the inoperable withdrawn control rod (s) by inserting the control rod (s) at least one notch by drive water pressure within the normal operating range **.

b) Otherwise, insert the inoperable withdrawn control rod (s) and disarm the associated directional control valves

  • either:
1) Electrically, or
2) Hydraulically by closing the drive water and exhaust water isolation valves "May be rearmed intermittently, under administrative control, to permit testing associated with restoring the control rod to OPERABLE status.

(

LA SALLE - UNIT 2 3/4 1-3 Amendment No. 53

REACTIVITY CONTROL SYSTEM LIMITING CONDITION FOR OPERATION (Continued)

ACTION (Continued)

2. If the inoperable control rod (s) is inserted:

a) Within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> disarm the associated directional control valves

  • either:
1) Electrically, or
2) Hydraulically by closing the drive water and exhaust water isolation valves, b) Otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, cru < < 3. The provisions of Specification 3.0.4 are not applicable, b' b j c. With more than 8 control rods inoperable, be in at least HOT SHUTDOWN s u within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

( SURVEILLANCE REQUIREMENTS 4.1.3.1.1 The scram discharge volume drain and vent valves shall be demonstrated OPERABLE by:

a. At least once per 31 days verifying each valve to be open**, and
b. At least once per 92 days cycling each valve through at least one complete cycle of full travel.

4.1.3.1.2 When above the low power setpoint of the RWM and RSCS, all withdrawn control rods not required to have their directional control valves disarmed electrically or hydraulically shall be demonstrated OPERABLE by moving each control rod at least one notch:

a. At least once per 7 days, and
b. At least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when any control rod is imovable as a result of excessive-friction or mechanical interference.

4.1.3.1.3 All control rods shall be demonstrated OPERABLE by performance of Surveillance Requirements 4.1.3.2, 4.1.3.4, 4.1.3.5, 4.1.3.6, and 4.1.3.7.

"May be rearmed intermittently, under administrative control, to permit testing associated with restoring the control rod to OPERABLE status.

I

    • These valves may be closed intermittently for testing under administrative control.

LA SALLE - UNIT 2 3/4 1-4

  • ~

REACTIVITY CONTROL SYSTEM SURVEILLANCE REQUIREMENTS (Continued)

. 4.1.3.1.4 The scram discharge volume shall be determined OPERABLE by demonstrating:?q

&' ,m

' A (' Jhe_ scram _ discharge volume drain _ and v_ent valy.es _0RER

/ control rods are scram fested from a normal control rod configura .

ktiqn of less than or equal to 50% ROD DENSITY .at'l~e~ait~once per' 18 MnEis{by verifying thiEIhe~d~r~iin and vent valves:

3 'h Close within 30 seconds after receipt of a signal for control rods to scram, and

} 'R. Open after__the scram signal is reset.

m

,- b. ProperfloatandlevelsensorresponsebyperformanceofaCHANNELh FUNCTIONAL TEST of the scram discharge volume scram and control rod )~q block level instrumentation at least once per 31 days. /

. . . ./'

(

l' OPERATIONAL CONDITION 2 provided the surveillance is perfor . a.__

k 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after achieving less than or equal to 50% R00 DENSITY.

N #

t LA SALLE - UNIT 2 3/4 1-5

i a

INSERT A

d. With one scram discharge volume vent valve and/or one scram discharge volume drain valve inoperable and open, restore the inoperable valve (s) to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
e. With any scram discharge volume vent valve (s) and/or any scram discharge volume drain valve (s) otherwise inoperable, restore the inoperable valve (s) to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

s ZNLD/1847/8

1 ATTACHMENT C Evaluation of Significarit Hazards Consideration Commonwealth Edison has evaluated the proposed Technical Specification Amendment and determined that it does not represent a significant hazards consideration. Based on the criteria for defining a significant hazards consideration established in 10 CFR50.92, operation of LaSalle County Station Units 1 and 2 in accordance with the proposed amendment will not:

1) Involve a significant increase in the probability or consequences of an accident previously evaluated because; The deletion of the requirement for control rods to be withdrawn to perform surveillance requirement 4.1.3.1.4.a and the associated Note
  • does not increase the probability or consequences of a previously evaluated accident. This is ustified because the ability of the valves to close in the required time and reopen s still tested, and the difference in initial test conditions has little affect on the results of the test. Therefore operability of the SDV Vent and Drain valves is verified by performing the surveillance in shutdown conditions.
2) Create the possibility of a new or different kind of accident from any accident previously evaluated because:

The change to the initial conditions for the SDV vent and drain valve timing does not involve any changes to the facility or the operation of the facility as described in the UFSAR.

3) Involve n significant reduction in the margin of safety because:

There is not an overall significant reduction in the margin of safety. Conducting the test at a reduced pressure may be considered a minor reduction in the margin of safety; however, this is mitigated by the increase in safety as a result of eliminating a required scram from high reactor pressure and low power (5 to 15%), which -

challenges safety systems on an 18 month frer3uency. The closin,g time of the SDV vent and dra,in valves is minimally effected by the change in initial conditions because the SDV is of sufficient size and is initially vented such that peak pressure

- prior to the closing of the valves is not substantial. The current Technical Specification requires demonstrating the reopening capability of the SDV vent and drain valves against a high backpressure (normal operating reactor pressure) and with this amendment the backpressure will normally be low during the performance of this surveillance. However, the ability of the valves to open against rated pressure would be demonstrated after a reactor scram during normal operation or, if failure to reopen occurred, then repairs would have to be done prior to startup.

Therefore, conducting this surveillance during shutdown is acceotable due to the minimal effect on surveillance results and the increased safety c ue to less challenges to safety systems.

ZNLD/1847/9

Guidance has been provided in " Final Procedures and Standards on No Significant Hazards Considerations," Final Rule,51 FR 7744, for the application of standards to license change requests for determination of the existence of significant hazards considerations. This document provides examples of amendments which are and are not considered likely to involve significant hazards considerations. This -

proposed amendment most closely fits the example of a change which may result in some increase to the probability or consequences of a prev lously analyzed accident or may reduce in some way a safety margin, but where the results of the change are clearly within all acceptable criteria with respect to the system or components specified in the Standard Review Plan. Since these changes are to-the surveillance requirements for determining valve operability, these changes are clearly within the acceptance criteria of sections 3.9.4 and 4.6 of the Standard Review Plan. This pro:>osed supplemental amendment does not involve a-significant relaxation oi the criteria used to establish safety limits, a significant relaxation of the bases for the limiting safety system settings or a significant relaxation of the bases for the limiting conditions for operations. Therefore, based -

on the guidance provided in the Federal Register and the criteria established in 10-CFR50.92(c), the proposed changes does not constitute a significant hazards -

consideration.

ZNLD/1847/10

9 ATTACHMENT D Environmental Assessment Statement Applicability Review Commonwealth Edison has evaluated the proposed amendment against the criteria for the identification of licensing and regulatory actions requiring environmental assessment in accordance with 10 CFR51.21. It has been determined that the proposed change meets the criteria for a categorical exclusion as provided for under 10 CFR51.22(c)(9). This determination is based on the fact that this change is being proposed as an amendment to a license issued pursuant to 10 CFR50. This proposed change involves no significant hazards consideration or a significant change in the types or significant increase in the amounts of any effluents that may be released offsite. In addition, this amendment request does not involve a significant increase in Individual or cumulative occupational radiation exposure.

ZNLD/1847/11

l 4'

ATTACHMENT E-Additional Support Material-A. Appropriate pages of LaSalle UFSAR B. Simplified SDV drawing C. Appropriate pages of Technical Specifications for_.the following plants:

River Bend Unit 1, NUREG-1172, November 1985 -

3

-'ZNLD/1847/12 -

LSCS-UTSAR 4.6.1.1.2.4.2.3 Drive Water Pressure Drive water pressure required in the drive header is maintained by the drive pressure control valve, which is ranually adjusted from the control room. A flow rate of approxime,tely 6 gpm (the sum of the flo- rate required to insert and withdraw a control rod) normally passes from the drive water pressure stage through two solenoid-operated stabilizing valves (arranged in parallel) ,

and then goes into 'he cooling water line. The ' low through one stabilizing valve equals the drive insert flow; that of the other stabilizing valve equals the drive withdrawal flow, When-opertting a drive, the required flow is diverted to that drive by closing the appropriate stabilizing valve. Thus, flow through the drive pressure control valve is always constant.

Flow indicators in the drive water header and in the line downstream from the stabilizing valves allow the flow rate through the stabilizing valves to be adjusted when necessary.

Differential pressure between the reactor vessel and the drive pressure stage is indicated in the control room.

Cooling Water Header e 4.6.1.1.2.4.2.4 The cooling water header is located downstream from the drive pressure control valve. When not moving a CRD, all system flow returns to vessel through the cooling water header.-

The flow through t?. flow control valve is virtually constant.

Therefore, once ad3st.ed, the' drive pressure control valve maintains the required pressure independent of reactor pressure.

3 Changes in setting of the pressure controi 7alves are required only to aojust for changes in the cooling requirements of the drives, as their seal characteristics change with time. A flow indicator in the control room monitors cooling water flov, A differential pressure indicator in the control room indicates the difference between reactor vessel pressure and drive cooling water pressure. Although the drives can function without cooling water, seal life is shortened by long teen exposure to reactor temperatures. The temperature of each drive is recorded in the control roca, and excessive temperatures are annunciated.

4.6.1.1.2.4.2.5- Return Line The B2 0 discharged from the BCD during a normal control rod positioning operation is discharged back to the RPV through the insert / exhaust directional solenoid valves of adjoining BCOs.

s 4.6.1.1.2.4.2.6 Scram Discharoe Volume The scram discharge volume consists of header piping which The connects to each BCD and drains into an instrument' volume.

header piping is sized to receive and contain all the water discharged by the drives during a scran, independent of the instrument volume.

4.6-10 REV. 0 - APRIL 1984

LSCS-UPSAR During normal plant operation the scram discharge volume is empty and ventec to atmosphere through its open vent and drain valve. When a scram occurs, upon a signal from the safety circuit. these vent and drain valves are closed to conservc reactor water. L.ghts in the control room indicate the position of these valves.

Dur'.ng a scram, the scram discharge volume partly fills with water discharged from above the drive pistons. Vhile scrammed, the control rod drive seal leakage from the reactor continues to flow into the scram discharge volume until the discharge volume pressure equals the reactor vessel pressure. A check valve in each HCU prevents reverse flow from the scram discharge header volume to the drive. When the -initial scram signal is cleared from the reactor protection system, the scram discharge volume signal is overridden with a keylock override switch, and the scram discharge volume is drained and returned to atmospheric pressure.

Remote manual switches in the pilot valve solenoid circults allow the discharge volume vent and drain valves to be tested without disturbing the .

reactor protection system, closing the scram discharge volume valves allows the outlet scram valve seats to be leaktested by timing the accumulation of leakage inside the scram discharge volume.

Six liquid-level switches are-connected to aech instrument volume to monitor l the volume for abnormal water level. TP> ere set at three different levels.

At the lowest level, a level switch actus'.ea to indicate that the volume is not completely empty during postscram draining or to indicate that the volume starts to fill through leakage accumulation at other times during reactor operation. At the second level, one level switch produces rod withdrawal block to prevent turther withdrawal of any control rod when leakage accumulates to approximately half the capacity of the instrument volume. The remaining four level switches are interconnected with the trip channels of the l reactor protection system (RPS) and will initiate a reactor scram should water accumulation fill the instrument volume. Two of these scram switches are float type and two are differential pressure type. All Four Scram Switches are interconnected to the essential service Bus, with Two switches in each division.

Redundant Vent & Drain Valves, placed in series, are located in the vent and drain piping for the scram discharge volume.

This system configuation is in compliance with those guidelines given in IF.

Bulletin No. 80-17.

9 4.6-11 REV. 3 - APRIL 1987

). .. .. . .

1 flwas.

NEIAT2DLECRM_PlSCRMGg_yowgg _

h.$.'*/v' VENT TO RWCM p3gg relASC KEPARATO A , ,

. . AAGM EC.

I- r r

, . .h l s py y

[ sov ] ( c

~

C / kb 0 s A

/ h ~5 e o (A

t j s" *

~

$Al>E9

~

, [u-N0'll gsv' i p,g,,

% FLCAT TYVE LEVEL SWRCHES y see

  1. .DIFFEA5NTIAL 9AESSut5 TAANSmirrEAS t, $EL 8' -

MDicATCATRIPIAMlT9.

ea44'd ptspf

REACTIVITY CONTROL SYSTEMS _

3/4.1.3 CONTROL R005 CONTROL R00 OPERA 8!LITY LIMITING CONOTTION FOR OPERATION 3.1.3.1 All control rods shall be OPERABLE.

APPLICA8ILITY: OPERATIONAL CONDITIONS 1 and 2.

ACTION:

a. With one control rod inoperable due to being immovable, as a result of excessive friction or mechanical interference, or known to be untrippable:
1. Within one hour: ,

a) Verify that the inoperable control rod, if withdrawn, is separated from all other inoperable control rods by at least two control cells in all directions.

Disarm the associated directional cs roi valves

  • either:

b)

1) Electrically or
2) Hydraulically by closing the drive watr,r and eihaust water isolation valyes.

Otherwise, be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

2. Comply with Surveillance Requirement 4.1.1.c.
3. Restore the inoperable control rod to GPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
b. With one or more control rods trippable but inopereble for cause ' other than addressed in ACTION a, abova:
1. If the inoperable control rod (s) is withdrawn, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />; a) Verify that the inoperable withdrawn control rod (s) is separated from all other iroperable control rods by at least two control cells in all dir":tions and b) Demonstrate tha insertion capability of the inoperable withdrawn control rod (s) by inserting the control rod (s) at least one notch by drive water pressure within the normal operating range **.
  • May be rearned intermittently, under administrative control, to permit testing associated with restoring the control rod to OPERA 8LE status.

3/4 1-3 CLINT01 - UNIT 1

REACTIVITY CONTROL SYSTEMS CONTROL R00 OPERABILIT_Y LIMITING CONDITION FOR OPERATION (Continued) 3.1.3.1 ACTION (Continued):

Othentise, insert the inoperable withdrawn control rod (s) and disarm the associated directional control valves" either:

a) Electrically or b) Hydraulically by closing the drive water and exhaust water isolation vaives.

2. If the inoperable control rod (s) is inserted, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> disarm the associated directional control valves
  • either:

a) Electrically or b) Hydraulically by closing the drive water and a haust water isolation valves. . .

Othentise, be in at least HOT SHUTDON within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. .

3. The provisions of Specification 3.0.4 are not applicable.

a With more than 8. control rods inoperable, be in at least HOT SHUTDOWN c.

within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. ,

, ,j

d. With one scram dischargs volume , vent valve and/or one scram discharge volume drain valve inoperable and open, restore the inoperable valve (s) to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
a. With any scram discharge volume vent valvs(s) and/or any scram discharge vol-uma drain valve (s) otherwise inoperable, restore the inoperable valves (s) to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.1.3.1.1 The scram discharge volume drain and vent valves shall be demon-strated OPERABLE by:

a. 'At least once per 31 days verifying each valve to be open** and ,
b. At least once per 92 days cycling each valve through at least one complete cycle of full travel.

"May be ' rearmed intermittently, under administrative control, to permit tasting associated with restoring the control rod to OPERABLE status.

    • These valves may be closed intermittently for testing under administrative ,

controls.

CLINTON - UNIT 1 3/4 1-4 .

s .' . .1 ' ' 'h A .

REACTIVITY CONTROL SYSTEMS CONTROL R00 OPERA 81LITY, SURVEILLANCE REQUIREMENTS (Continued)__

4.1.3.1.2 hn abeve the low power setpoliit of the RPCS or hydraulically shall be demonstrated CPERABLE by moving each control rod

) least one notch:

a. At least once per 7 days and b.

At least once per 24 Lours when any control rod is innovable as a nsult of excessive friction or mechanical interference.

4.1.3.1.3 All control rods shall be demonstrated OPERABLE by performance of Surveillance Requirements 4.L3.2, 4.L3.3, 4.L 3.4 and 4.L3.5.

4.h 3.1.4 The scras discharge volume shall be determined OPERA 8LE by demonstrating the scres discharge volume drain and vent valves are OPERA 8LE at least once per 18 months, by verifying that the drain and vent valves:

} Close within 30 seconds after receipt of a signal for control rods a.

to seres and

b. Open when.the seres signal is reset.

CLINTON - UNIT 1 3/4 1-5

4 3/4.1 REACTIVITY CONTROL SYSTEMS sASES 3/4.1.1 SHUTDOWN MARGIN A sufficient SHUTDOWN MARGIN ensures that (1) the reactor can be made sub-critical from all operating conditions, (2) the reactivity transients associated with postulated accident conditions are controllable within acceptable limits, and (3) the reactor will be saintained sufficiently suberitical to preclude inadvertent criticality in the shutdown condition.

Since core reactivity values will vary through core 1tfe as a function of fuel depletion and poison turnup, the demonstration of SHUTDOWN MARGIN will be para formed in the culd. :snon-free condition and shall show the core to be swr-critical by at least R + 0.385 A k/k or R + 0.285 A k/k, as appropriat9. The value of R in units of X A k/k is the difference between the esictilated value of maximum core reactivity during the opersting cycle and the calculated begin-ning-of-life core reactivity. The value of R ast' te positive or zero and must be determined for each fuel loading cycle.

Two different values are supplied in the Limiting Condition for Operation to '

provice for the different methods of demonstration of the SHUTDOWN MARGIN. The 1

highest worth rod any be determined analytically or by tast. The SHUTDOWN J MARGIN is demonstrated by an insequence control rod withdrawal at the begin-

.ning of life fuel cycle conditions, and, if necessary, at any future time in 2.he cycle if the first demonstration indicates that the required margin could be reduced as a function of exposure. Observation of subcriticality in this condition assures subcriticality with the most reactive control rod fully withdrawn.

This reactivity characteristic has been a basic assumption in the analysis of plant performance and can be best demonstrated at the time of fuel loading, but the margin must also bo determined anytime a control rod is incapable of insertion.

3/4.1.2 REACTIVITY ANOMALIES Since the SHUTDOWN MARGIN requirement for the reactor is small, a careful check on actual conditions to the predicted conditions is necessary, and the changes in reactivity can be inferred from these comparisons of rod patterns. Since the comparisons are easily done, frequent checks are not an imposition on normal operations. A 1% change is larger than is expected for normal operation so a change of this magnitude should be thoroughly evaluated. A change as large as 1% would not exceed the design conditions of the reactor and is on the safe side-of the postulated transients.

3/4.1.3 CONTROL RODS The specification of this section ensure that (1) the minimus SHUTDOWN MARGIN is maintained, (2) the control rod insertion times tre consistent with those used in the safety analyses, and (3) limit the potantial effects of the rod drop accident. The ACTION statements permit variations from the basic requirements but at the same time impose more restrictive critaria for continued operation.

CLINTON - UNIT 1 8 3/4 1-1

REACTIVITY CONTROL SYSTEMS BASES 3/4.1.3 CONTROL RODS (Continued)

A limitation on inoperable rods is set such that the resultant effect on total rod worth and scraa shape will be kept to a sintaus. The requirements for the various scras time measurements ensure that any indication of systematic pro-blems with rod drives will be investigated on a timely basis.

Damage within the control rod drive mechanisa :ould be a generic probles, there-fore with a control rod immovable because of excessive friction or mechanical interference, operation of the reactor is limited to a time period which is reas' enable to determine the cause of the inoperability and at the same time prevent operation with a large number of inoperable control rods.

Control rods that are inoperable for other reasons are permitted to be taken out of service provided that those in the nonfully-inserted position are con-sistent with the SHUTDOWN MARGIN requirements.

The number of control rods permitted to be inoperable could be more than the eight allowed by the specification, but the occurrence of eight inoperable rods could be indicative of a generic probles and the reactor must be shut down for investigation and resolution of the problem.

The control rod system is designed to bring-the reactor suberitical at a rate fast.enough to prevent the MCPR from becoming less than the fuel cladding safety limit during the limiting power transient analyzed in Section 15.4 of the FSAR.

This analysis shows that the negative reactivity rates resulting from the scram with the average response of all the drives as given in the specifications, provide the required protection and MCPR remains knater than the fuel cladding safety limit. The occurrence of scras times longer then those specified should be viewed as an indication of a systemic problem with the rod drives and there-fore the surveillance interval is reduced in order to prevent operation of the reactor for long periods of time with a potentially serious problem.

The scran discharge volume is required to be OPERABLE so that it will be avail-able when needed to accept discharge water from the control rods during a reactor seras and will isolate the reactor coolant system from the containment when required.

Control rods with inoperable accumulators an declared inoperable and Specifi-cation 3.1.3.1 then applies. This prevents a pattern of inoperable accumulators that would result in less reactivity insertion on a scram thar. has been analyzed even though, control rods with inoperable accumulators may still be inserted with normal drive water pressure. Operability of the accumulator ensures that there is a means available to insert the control rods even under the most unfavorable depressurization of the reactor.

Control rod coupling integrity is required to ensure compliance with the analAis of the rod drop accident in the FSAR. The overtravel position feature provides the only poritive means of determining that a rod is properly coupled and there-fore this check must be performed prior to achieving criticality after completing CLINTON - UNIT 1 B 3/4 1-2

REACTIVITY CONTROL SYSTEMS i-

+

t

' EASES 3/4.1.3 CONTROL R005 (Continued)

CORE ALTERATIONS that could have affected the control rod coupling integrity. .

The subsequent check is perfomed as a backup to the initial demonstration.

In order to ensure that the control rod patterns can be followed and therefore that other parameters are within their limits, the control rod position indica-tion system must be OPERABLE. s The control rod housing support restricts the outward movement of a control rod >

7 to less than 3 inches in the event of a housing failure. The amount of rod  ;

reactivity which could be added by this-small amount of r2d withdrawal is less -

than a nomal withdrawal-increment and will- not contribute to any damage to the

- primary coolant system. The support is not required when there is no pressure to act as a driving force to rapidly, eject a drive housing.

The required surveillance intervals are. adequate to datamine that the rods are -

OPERA 8LE and not s,o frequent as to cause excessive we.r on the systes components.

3/4.1.4 CONTROL R00 PROGRAM CONTROLS The rod withdrawal limitar system input power signal orginates frw the ff rst stage tuttine pressure. When operating with the steam bypass valvet open, this signal indicates a core power level W ch is less than the true core odwer.

Consequently, near the low power setpoint and high power setpoint of \he rod -

pattern control system, the potential exists for nonconservative contrel rod withdrawals. Therefore, when operating at a sufficiently high power le'el, there is a small probability of violating fuel- Safety Limits during a licensing basis rod withdrawal error transtant. -To ensure that fuel safety Limits are not violated,-this specification prohibits control rod withdrawal when a biased power signal exists and core power _-exceeds the specified level.

Control rod withdrawal and insertion sequences are established to assure that the maximum insequence individual control . rod or control rod segments which are withdrawn at any time during the fuel cycle could not be worth enough to result in a peak fuel enthalpy greater than 280 cal /gm in the event of a control rod drop accident. The specified sequences are characterized by homogeneous, scat-tered patterns of control rod withdrawal. When THERMAL POWER is greater than - '

20% of RATED Tr" MAL POWER, there is no possible rod worth which, if dropped at.

the design rate of the velocity limiter, could result in a peak enthalpy of 280 cal /gm. Thus requiring the RPCS to be OPERABLE when THERMAL POWER is less than or equal to 20% of RATED THERMAL POWER provides adequate control.

The RPCS provide automatic supervision t.o assure that out-of-sequence rods will not he withdrawn or inserted.

CLINTON - UNIT 1 ,

8 3/4 1-3

-- -- _ _ _ _ - _ _ _ - _ _ _ _ _ . _ _ _ _ _ __ - - - - - - - - - - - - ______m____ _ ___ ___ __ _____

REACTIVilY CONTROL SYSTEMS SURVEltLANCE REQUIREK NTS (Continued) __

4.1.3.1.3 All control rods shall be demonstrated OPERA 8LE by performance of Surveillance Requirements 4.1.3.2, 4.1.3.3, 4.1.3.4 and 4.1.3.5.

4.1. 3.1. 4 The scran discharge volume shall be detarsined OPERA 8LE by demonstrating:

a. The scran discharge volume crain and vent valves OPERA 8LE at least once per 13 months by verifying that the drain and vent valves:
1. Close within 10 seconds after receipt of a signal for control rods to scras, and
2. Open when tne scras signal is reset.
b. Proper level sens r response by performance of a CHANNEL FUNCTIONAL TEST of the scram discharge volume scram and control rod block level instrumentation at least once per 31 days.

2 PERRY - UNIT 1 3/4 1-5

a l

REACTIVITY CONTROL SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) 4.1.3.1.3 All control rods shall be demonstrated CPERA8LE by performance of Survalliance Requirements 4.1. 3. 2, 4.1. 3. 3, 4.1. 3. 4 and 4.1. 3. 5.

4.1.3.1.4 The scran discharge voltne shall be determined OPERABLE by demonstrating th< scram discharge volume drain and vent valves OPERABLE, at least coce per 18 months, by verifying that the drain and vent valves:

a. Close within 30 seconds af ter receipt of a signal for control rods to scram, and
b. Open when the scraa signal is reset.

RIVER 3END - UNIT 1 3/4 1-5

- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _

Retrieved from "https://kanterella.com/w/index.php?title=ML20097D927&oldid=2782246"