Text

Amend 234 to License DPR-56,changing TS in Response to 990301 Application & Suppls ,1001 & 06,to Support PBAPS Mod P00507,which Will Install Digital Pr Neutron Monitoring Sys
	ML20217K976
Person / Time
Site:	Peach Bottom
Issue date:	10/14/1999
From:	Clifford J; NRC (Affiliation Not Assigned)
To:	;
Shared Package
ML20217K929	List: ML20217K924; ML20217K976; ML20217K993;
References
	NUDOCS 9910270041
	Download: ML20217K976 (48)
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l p e vea \

p% 1 UNITED STATES l g j t

NUCLEAR REGULATORY COMMISSION o WASHINGTON, D.C. 2066&4001 i

.s**

PECO ENERGY COMPANY l

PUBLIC SERVICE ELECTRIC AND GAS COMPANY l DELMARVA POWER AND LIGHT COMPANY ATLANTIC CITY ELECTRIC COMPANY l l

DOCKET NO. 50-278 PEACH BOTTOM ATOMIC POWER STATION. UNIT NO. 3 l l

AMENDMENT TO FACILITY OPERATING LICENSE I

, Amendment No. 234 License No. DPR 56

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by PECO Energy Company, et al. (the licensee) dated March 1,1999, as supplemented June 14, October 1, and October 6,1999, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I.

B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (i@ that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied. t

2. Accord.ngly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C(2) of Facility Operating License No. DPR-56 is hereby amended to read as follows:

9910270041 991014 PDR ADOCK 05000278 P PDR

(2) Technical Soecifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 234 , are hereby incorporated in the license. PECO shall operate the facility in accordance with the Technical Specifications.

3. This license amendment is effective as of its date of issuance and shall be implemented prior to restart from the Peach Bottom Atomic Power Station, Unit 3, October 1999 refueling outage.

FOR THE NUCLEAR REGULATORY COMMISSION Ja es W. Clifford, hief, Section 2 Project Directorate l Division of Licensing Project Management Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance: (ttober 14, 1999

l L

ATTACHMENT TO LICENSE AMENDMENT NO. 234 l

FACILITY OPERATING LICENSE NO. DPR 56 !

I DOCKET NO. 50-278

( Replace the following pages of the Appendix A Technical Specifications with the attached !'

l revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

Remove insert l 3.3-1 3.3-1 !

3.3-4 3.3-4 i 3.3-5 3.3-5 I 3.3-6 3.3-6 !

3.3-7 3.3-7 3.3-18 3.3-18 l

3.3 19 3.3-19 3.3 20 3.3-20 3.3-21 3.3-21 3.4-1 3.4-1

! 3.10-20 3.10-20 3.10 22 3.10-22 B3.3-7 B3.3-7 I

B3.3-8 B3.3-8 !

B3.3-9 B3.3-9 B3.3-10 B3.311 B3.3-10 B3.3-11

)

' B3.312 B3.3-12 B3.3-23 B3.3-23 B3.3-24 B3.3-24 B3.3 '

B3.3-25 B3.3 26 B3.3-26 B3.3-27 B3.3-27 B3.3-28 B3.3-28 B3.3-29 B3.3 29 B3.3-30 B3.3-30 B3.3 31 B3.3-31 :

B3.3-32 B3.3-32 !

. B3.3-33 B3.3-33 B3.3-34 B3.3-34

= B3.3 35 B3.3-35 B3.3-36 B3.3-36 B3.3-46 B3.3-46 i

l 1

l

o s ..

, l ATTACHMENT TO LICENSE AMENDMENT NO. 234 i FACILITY OPERATING LICENSE NO. DPR-56 DOCKET NO; 50-278 4

Replace the following pages of the Appendix A Technical Specifications with the attached revised pages. The rc' ised pages are identified by amendment number and contain marginal lines indicating the areas of change.

Remove Insert B3.3-47 B3.3-47 B3.3 53 B3.3-53 B3.3-54 B3.3-54 B3.3-55 B3.3-55 B3.3-56 B3.3-56 B3.3-58 B3.3-58 B3.4-3 B3.4-3 ,

B3.4-5 B3.4 5 ,

B3.4-6 B3.4-6 B3.10-32 83.10.32 B3.10-35 B3.10-35 L

l 1

E RPS Instrumentation 3.3.1.1-3.3 INSTRUMENTATION-.

3.3.1.1 Reactor Protection System (RPS) Instrumentation

.LC0 _3.3.1.1 The RPS instrumentation for each Function in Table 3.3.1.1-1

'shall- be OPERABLE.

APPLICABILITY: According to Table 3.3.1.1-1.

l l ACTIONS ~

_____________________________________ NOTE-------------------------------__--__

Separate

_________' Condition entry is allowed for each channel .

CONDITION REQUIRED ACTION COMPLETION TIME A. 'One or more required A.1 Place channel in 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months channels inoperable. trip.

, M L

l- A.2 --------NOTE--------- 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months l' Not applicable for Functions 2.a, 2.b, 2.c, or 2.d.

Place associated trip system in trip.

l B. ---------NOTE--------- B.1 Place channel in one 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Not applicable ~ for trip system in trip.

Functions 2.a, 2.b, 1 E

2.c, or-2.d.

~

One or more Functions- B.2 Place one trip system 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months with one or more in trip.

required channels-inoperable-in both tr_ip systems.

1 (continued) l PBAPS UNII;3 3.3 I Amendment No.214,234

)

RPS Instrumentation 3.3.1.1 SURVEILLANCE REQUIREMENTS (continued) l-SURVEILLANCE FREQUENCY l- SR 3.3.1.1.3 (Not Used.)

l SR 3.3,1.1.4 - Perform CHANNEL FUNCTIONAL TEST. 7 days SR 3.3.1.1.5 -----------------NOTE-------------------

Not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2.

l Perform CHANNEL FUNCTIONAL TEST 31 days SR 3.3.1.1.6 Perform CHANNEL FUNCTIONAL TEST. 31 days l

l' SR 3.3.1.1.7 (Not Used.)

l

~

SR 3.3.1.1.8- Calibrate the local power range monitors. 1000 MWD /T aveiage core expo'.ure (continued) t i

PBAPS UNIT 3 3.3-4 Amendment No. 224,234 l

l J

r i i

L RPS Instrumentation 1 3.3.1.1 j l

SURVEILLANCE REQUIREMENTS (continued) , , ,

SURVEILLANCE FREQUENCY SR 3.3.1.1.9 Perform CHANNEL FUNCTIONAL TEST. 92 days 1

SR 3.3.1.1.10 ------------------NOTE-------------------

Radiation detectors are excluded. !

Perform CHANNEL CALIBRATION. 92 days .

4 SR 3.3.1.1.11 -------

NOTES------------------

l 1. For Function 2.a, not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2.

2. For Function 2.b, the CHANNEL FUNCTIONAL TEST includes the ;

recirculation flow input processing, )

excluding the flow transmitters.

l Perform CHANNEL FUNCTIONAL TEST. 184 days i

SR 3.3.1.1.12 ------------------NOTES------------------

1. Neutron detectors are excluded.

l 2. For Function 1, not required to be performed when entering MODE 2 from ,

MODE 1 until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering j MODE 2. t i

3. For Function 2.b, the recirculation l flow transmitters that feed the APRMs are included.

\

l Perform CHANNEL CALIBRATION. 24 months i l

i (continued) !

I I

PBAPS UNIT 3 3.3-5 Amendment No. 223, 234 j

l. i l ,

l

4

. j RPS Instrumentation 3.3.1.1 SURVEILLANCE REQUIREMENTS (continued)

-SURVEILLANCE FREQUENCY SR 3.3.1.1.13 Verify Tu' rbine' Stop Valve-Closure and 24 months Turbine Control Valve Fast Closure, Trip 011 Pressure-Low Functions are not-bypassed when THEFSAL POWER is a 30% RTP.

SR 3.3.1.1.14 Perform CHANNEL FUNCTIONAL TEST. 24 months .

SR--3.3.1.1.15 Perform CHANNEL CALIBRATION. 24 months SR 3.3.1.1.16 Calibrate each radiation detector. 24 months SR 3.3.1.l'.17 Perform LOGIC SYSTEM FUNCTIONAL-TEST. 24 months SR 3.3.1.1.18 Verify the RPS RESPONSE TIME is within' 24 months limits.

PBAPS UNIT 3 3.3-6 Amendment No. 222, 234

RPS Instrumentation 3.3.1.1 l l

Table 3.3.1.1 1 (page 1 of 3)

Reactor Protection System Itstrumen:ation APPLICABLE CONDITIONS MODES OR REQUIRED REFERENCED OTHER CHANNELS FROM SPECIFIED PER TRIP REQUIRED SURVEILLANCE ALLOWABLE FUNCTION CONDITIONS $YSTEM ACTION 0.1 REQUIREMENTS VALUE l

1. Wide Range Neutron Monitors 1

e. Period-Short 2 3 G SR 3.3.1.1.1 2 13 seconds l SR 3.3.1.1.5 i SR ~3.3.1.1.12 l SR 3.3.1.1.17 I SR 3.3.1.1.18 j 5(a) 3 H SR 3.3.1.1.1 a 13 seconds l SR 3.3.1.1.6 l SR 3.3.1.1.12 i SR 3.3.1.1.17 j SA 3.3.1.1.18 l

b. Inop 2 3 G SR 3.3 1.1.5 NA SR 3.3.1.1.17 5(a) 3 H SR 3.3.1.1.6 NA j SR 3.3.1.1.17 '

2. Average Power Range Monitors

a. Neutron Flux High 2 3(C) G SR 3.3.1.1.1 5 15.0% RTP (Setdown) SR 3.3.1.1.8 SR 3.3.1.1.11 SR 3.3.1.1.12

b. Simulated Thermal 1 3(C) F SR 3.3.1.1.1 5 0.66 W Power-Nigh SR 3.3.1.1.2 + 64.9% RTPID) i and 5 118.0%

RTP 6

SR 3.3.1.1.8 SR 3.3.1.1.11 SR 3.3.1.1.12

c. Neutron Flux High 1 358) F SR 3.3.1.1.1 5 119.7% RTP SR 3.3.1.1.2 l SR 3.3.1.1.8 SR 3.3.1.1.11 SR 3.3.1.1.12

d. 'Inop 1,2 3(*) G SR 3.3.1.1.11 NA

e. 2 Out 0f-4 Voter 1,2 2 G SR 3.3.1.1.1 NA SR 3.3.1.1.11 SR 3.3.1.1.17 SR 3.3.1.1.18 (continued)

(a) With any control rod withdrawn from a core cett containing one or more fuel assen6 ties.

l(b) 0.66 W + 64.9% 0.66 AW RTP when reset for single loop operation per LCO 3.4.1, Recirculation Loops Operating."

(c) Each APRM channet provides inputs to both trip systems.

PBAPS UNIT 3 3.3-7 Amendment No.22#, 234

l Control Rod Block Instrumentation 3.3.2.1 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME E. One or more Reactor E.1 Suspend control rod Immediately Mode Switch-Shutdown withdrawal.

Position channels

! inoperable. AND l

j E.2 Initiate actior to Immediately fully insert all insertable control rods in core cells containing one or more fual assemblies. l SURVEILLANCE REQUIREMENTS

NOTES------------------------------------

1. Refer to Table 3.3.2 ' to determine which SRs apply for each Control Rod Block Function.

2. When an RBM channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months provided the associated Function maintains control rod block capability.

SURVEILLANCE FREQUENCY

-l SR 3.3.2.1.1 Perform CHANNEL FUNCTIONAL TEST. 184 days (continued)

PBAPS UNIT 3 3.3-18 Amendment No. 214, 23;

I Control Rod Block Instrumentation l 3.3.2.1 l

, SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.3.2.1.2 ------------------NOTE-------------------

l Not required to be performed until I hour after any control rod is withdrawn at s 10% RTP in MODE 2.

Perform CHANNEL FUNCTIONAL TEST. 92 days SR 3.3.2.1.3 ------------------NOTE-------------------

Not required to be. performed until I hour ]

after THERMAL POWER is s'10% RTP. in MODE 1.

I 92 days Perform CHANNEL FUNCTIONAL. TEST.

SR 3.3.2.1.4 ------------------NOTE-------------------

Neutron detectors are excluded. l i

l Verify the RBM: 24 months

a. Low Power Range-Upscale Function is not bypassed when THERMAL POWER is

-l 2 28.4% RTP. {

I

b. Interrediate Power Range-Upscale l Function is not bypassed when THERMAL i l POWER is 2 63.4% RTP. t

c. High Power Range-Upscale Function is !

not bypassed when THERMAL POWER is l 2 83.4% RTP.

(contir.ued) s !

PBAPS UNIT 3 3.3_19 Amendment No.2#, 234 l

e Control Dod Block Instrumentation 3.3.2.1 SURVEILLANCE REQUIREMENTS (continued) i SURVEILLANCE FREQUENCY

'SR 3.3.2.1.5 ------------------NOTE-------------------

Neutron detectors are excluded.

l . Perform Ct.ANNEL CALIBRATION. 24 months SR 3.3.2.1.6. Verify the RWM is not bypassed when 24 months

. THERMAL POWER is s 10% RTP.

SR 3.3.2.1.7 ------

2----------NOTE-------------------

Not required to be performed until I hour i after reactor mode switch is in the shutdown position.

Perform CHANNEL FUNCTIONAL TEST. 24 months )

l l

SR 3.3.2.1.8 Verify control rod sequences input to the Prior to RWM are in conformance with BPWS. declaring RWM OPERABLE following loading of sequence into RWM l

l PBAPS UNIT 3 3.3-20 Amendment No. 2fft, 234

J' Control Rod Block Instrumentation 3.3.2.1 1 l

I l-l- Table 3.3.2.1 1 (page 1 of 1)

Control Rod Stock Instrunentation l

l l

APPLICABLE l MCOES 04 OTHER SPECIFIED REQUIRED SURVEILLANCE ALLOWABLE FUNCTION CON 0!TIONS CMANNELS REQUIREMENTS VALUE 1 Rod Stock Monitor

a. Low Power Range - Upscale (a) 2 SR 3.3.2.1.1 (h)

SR 3.3.2.1.4 SR 3.3.2.1.5

b. Intermediate Power (b) 2 SR 3.3.2.1.1 R ange - Upeca t e (h)

SR'3.3.2.1.4 SR 3.3.2.1.5 l c. nigh power Range -Upscale (c) 2 SR 3.3.2.1.1 (h) ,

SR 3.3.2.1.4 l SR 3.3.2.1.5

d. Inop (a) 2 SR 3.3.2.1.1 NA i

2. Rod worth Minimiter 1(f) 2, 0) - .1 SR 3.3.2.1.2 NA SR 3.3.2.1.3 SR 3.3.2.1.6

- SR 3.3.2.1.8 i

3. Reactor Mode Switch - Shutdoui (g) 2 SR 3.3.2.1.7 NA Position 1

1 l

l (a) THERMAL POWER t 28.4% RTP and MCPR less than the timit speelfled in the COLR. I l (b) THERMAL POWER t 63.4% RTP and MCPR tess than the limit specified in the COLR.

l l.(c)- TNiRMAL POWER a 83.4% and MCPR tess than the limit specified in the COLR.

l (d). Deleted.

l (e) Deleted.

.(f) With TNERMAL POWER s 10% RTP.

.(g) Reactor mode switch in the shutdown position.

(h) Less than or equal to the Allowable value specified in the COLR.

L PBAPS UNIT 3 3.3-21 Amendment No. 21#, 234 l

r ]

l L Recirculation Loops Operating 3.4.1 l

l 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.1 Recirculation loops Operating l

! l LC0 3.4.1 Two recirculation loops with matched flows shall be in operation with core flow as a function of THERMAL POWER in the " Unrestricted" Region of Figure 3.4.1-1.

DB One recirculation loop shall be in operation with torm flow as a function of THERMAL POWER in the " Unrestricted" Region j of Figure 3.4.1-1 and with the following limits applied when 1 the associated LC0 is applicable:

a. LC0 3.2.1, " AVERAGE PLANAR LINEAR HEAT GENERATION RATE (APLHGR)," single loop operation limits specific in the COLR; I

b. LC0 3.2.2, " MINIMUM CRITICAL POWER RATIO (MCPR)," single loop operation limits specified in the COLR; and

c. LC0 3.3.1.1, " Reactor Protection System (RPS)

Instrumentation," Function 2.b (Average Power Range l Monitors Simulated Thermal Powar-High), Allowable Value of Table 3.3.1.1-1 is reset for single loop operation.

NOTE----------------------------

-Required limit modifications for single recirculation loop l operation may be delayed for up to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after trantition from two recirculation loop operation to single recirculation loop operation.

APPLICABILITY: MODES 1 and 2.

PBAPS UNIT 3 3.4-1 Amendment No. 214,234 i

I

0 SDM Test-Refueling 3.10.8 3.10 SPECIAL OPERATIONS I

3.10.8 SHUTDOWN MARGIN (SDM) Test-Refueling I l I LC0 3.10.8 The reactor mode switch position specified in Table 1.1-1 l for MODE 5 may be changed to include the startup/ hot standby l position, and operation considered not to be in MODE 2, to l allow SDM testing, provided the following requirements are l met:

l a. LC0 3.3.1.1, " Reactor Protection System Instrumentation," MODE 2 requirements for Functions 2.a, 2.d and 2.e of Table 3.3.1.1-1;

b. 1. LC0 3.3.2.1, " Control Rod Block Instrumentation,"

MODE 2 requirements for Function 2 of Table 3.3.2.1-1, with the banked position withdrawal sequence requirements of SR 3.3.2.1.8 changed to require the control rod sequence to conform to the SDM test sequence, DE

2. Conformance to the approved control rod sequence for the SDM test is verified by a second licensed operator or other qualified member of the technical staff;

c. Each withdrawn control rod shall be coupled to the associated CRD;

d. All control rod withdrawals during out of sequence control rod moves shall be made in notch out mode;

e. No other CORE ALTERATIONS are in progress; and

f. CRD charging water header pressure 2 940 psig.

APPLICABILITY: MODE 5 with the reactor mode switch in startup/ hot standby position.

I

'PBAPS UNIT 3 3.10-20 Amendment No.214, 221, 234

i l l SDM Test-Refueling l 3.10.8 SUPVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY j 1

SR 3.10.8.1 Perform the MODE 2 applicable SRs for According to l LC0 3.3.1.1, Functions 2.a, 2.d and 2.e of the applicable Table 3.3.1.1-1. SRs SR 3.10.8.2 -------------------NOTE--------------------

Not required to be met if SR 3.10.8.3 satisfied.

Perform the MODE 2 applicable SRs for According to LC0 3.3.2.1, Function 2 of Table 3.3.2.1-1. the applicable SRs SR 3.10.8.3 -------------------NOTE--------------------

Not required to be met if SR 3.10.8.2

satisfied.

Verify movement of control rods is in During control compliance with the approved control rod rod movement sequence for the SDM test by a second licensed operator or other qualified member of the technical staff.

SR -3.10.8.4 Verify no other CORE ALTERATIONS are in 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months progress.

I (continued) l l

PBAP. UNIT 3 3.10-22 Amendment No.214, 234 I

1 L.

r RPS Instrumentation B 3.3.1.1 l

BASES i APPLICABLE 1.b. Wide Ranae Neutron Monitor-Inop (continued)

SAFETY ANALYSES, LCO, and Six channels of the Wide Range Neutron Monitor-Inop i APPLICABILITY Function, with three channels in each trip system, are required to be OPERABLE to ensure that no single instrument failure will preclude a scram from this Function on a valid signal. Since this Function is not assumed in the safety analysis, there is no Allowable Value for this Function.

This Function is required to be OPERABLE when the Wide Range Neutron Monitor Period-Short Function is required.

Averaae Power Ranae Monitor (APRM)

The APRM channels provide the primary indication of neutron flux within the core and respond almost instantaneously to neutron flux increases. The APRM channels receive input signals from the local power range monitors (LPRMs) within the reactor core to provide an indication of the power distribution and local power changes. The APRM channels average these LPRM signals to provide a continuous indication of average reactor power from a few percent to greater than RTP.

The APRM System is divided into four APRM channels and four 2-out-of-4 voter channels. Each APRM channel provides inputs to each of the four voter channels. The four voter channels are divided into two groups of two each, with each group of two providing inputs to one RPS trip system. The system is designed to allow one APRM channel, but no voter channels, to be bypassed. A trip from any one unbypassed APRM will result in a " half-trip" in all four of the voter channels, but no trip inputs to either RPS trip system. A trip from any two unbypassed APRM channels will result in a full trip in each of the four voter channels, which in turn results in two trip inputs into each RPS trip system, thus resulting in a full scram signal. Three of the four APRM channels and all four of the voter channels are required to be OPERABLE to ensure that no single failure will preclude a scram on a valid signal. In addition, to provide adequate coverage of the entire core, consistent with the design bases for the APRM functions, at least 20 LPRM inputs, with at least three LPRM inputs from each of the four axial levels at which the LPRMs are located, must be operable for each APRM channel, and the number of LPRM inputs that have i become inoperabl'e (and bypassed) since the last APRM i

calibration (SR 3.3.1.1.2) must be less than ten for each I APRM channel.

(continued)

PBAPS UNIT 3 8 3.3-7 Revision No.

A,enchent fb. 234

RPS Instrumentation B 3.3.1.1 BASES APPLICABLE 2.a. Averaae Power Ranae Monitor Neutron Flux-Hiah SAFETY ANALYSES, (Setdown) (continued)

LCO, and APPLICABILITY For operation at low power (i.e., MODE 2), the Average Power

} Range Monitor Neutron Flux-High (Setdown) Function is capable of generating a trip signal that prevents fuel damage resulting from abnormal operating transients in this power range. For most operation at low power levels, the l Average Power Range Monitor Neutron Flux-High (Setdown)

Function will provide a secondary scram to the Wide Range Neutron Monitor Period-Short Function because of the relative setpoints. At higher power levels, it is possible that the Average Power Range Monitor Neutron Flux-High (Setdown) Function will provide the primary trip signal for a corewide increase in power.

No specific safety analyses take direct credit for the

} Average Power Range Monitor Neutron Flux-High (Setdown)

Function. However, this Function indirectly ensures that before the reactor mode switch is placed in the run position, reactor power does not exceed 25% RTP when operating at low reactor pressure and low co(SL 2.1.1.1) re flow.

Therefore, it indirectly prevents fuel damage during significant reactivity increases with THERMAL POWER

< 25% RTP.

The Allowable Value is based on preventing significant increases in power when THERMAL POWER is < 25% RTP.

l The Average Power Range Monitor Neutron Flux-High (Setdown)

Function must be OPERABLE during MODE 2 when control rods may be withdrawn since the potential for criticality exists.

l In MODE 1, the Average Power Range Monitor Neutron Flux-High Function provides protection against reactivity transients and the RWM and rod block monitor protect against control rod withdrawal error events.

2.b. Averaae Power Ranae Monitor Simulated Thermal Power-Hiah l The Average Power Range Monitor Simulated Thermal Power-High Function monitors average neutron flux to approximate the THERMAL POWER being transferred to the reactor coolant. The APRM neutron flux is electronically filtered with a time constant representative of the fuel heat transfer dynamics to generate a signal proportional to the THERMAL POWER in the reactor. The trip level is varied.as a function of recirculation drive flow (i.e., at lower core flows, the setpoint is reduced proportional to the reduction in power experienced as core flow is reduced with a fixed control rod pattern) but is clamped at an upper limit that is always lower than the Average Power Range Monitor Neutron Flux-High Function Allowable Value.

(continued)

PBAPS UNIT 3 B 3.3-8 Revision No.

Anenchent No. 234 e . . .

[

RPS Instrumentation B 3.3.1.1 l

BASES l APPLICABLE 2.b. Averaae Power Ranae Monitor Simulated Thermal SAFETY ANALYSES, Power-Hiah (continued)

LCO, and l APPLICABILITY The Average Power Range Monitor Simulated Thermal Power-High Function is not specifically credited in the safety analysis but is intended to provide an additional margin of protection from transient induced fuel damage during operation where recirculation flow is reduced to below tb9 minimum required for rated power operation. The Averagt Power Range Monitor Simulated Thermal Power-High Function provides protection against transients where THERMAL POWER increases slowly. (such as the loss of feedwater heating event) and protects the fuel cladding integrity by ensuring ;

that the MCPR SL is not exceeded. During these events, the THERMAL POWER increase does not significantly lag the neutron flux scram. For rapid neutron flux increase events, the THERMAL POWER lags the neutron flux and the Average '

Power Range Monitor Neutron Flux-High Function will provide a scram signal before the Average Power Range Monitor Simulated Thermal Power-High Function setpoint is exceeded.

Each APRM channel uses one total drive flow signal representative.of total core flow. The total drive flow signal is generated by the flow processing logic, part of the APRM channel, by summing up the flow calculated from two flow transmitter signal inputs, one from each of the two recirculation loop flows. The flow processing logic OPERABILITY is part of the APRM channel 0PERABILITY i requirements for this Function. The APRM flow processing '

logic is considered inoperable whenever it cannot deliver a flow signal less than or equal to actual Recirculation flow conditions for all steady state and transient reactor l conditions while in Mode 1. Reduced or Downscale flow conditions due to planned maintenance or testing activities during derated plant conditions (i.e. end of cycle coast down) will result in conservative setpoints for the APRM >

Simulated Thermal Power-High function, thus maintaining that ;

function operable.

(continued)

]

1 l

l !

l PBAPS UNIT 3 8 3.3-9 Revision No. )

t kend1ent No. 234 i

u j

l RPS Instrumentation !

B 3.3.1.1 !

BASES i

~ APPLICABLE 2.b. Averaae Power Ranae Monitor Simulated Thermal SAFETY ANALYSES, Power-Hiah (continued)

LCO, and _

APPLICABILITY The Allowable Value is based on analyses that take credit for the Average Power Range Monitor Simulated Thermal Power-High Function for the mitigation of non-limiting events. l The THERMAL POWER time constant of < 7 seconds is based on '

the fuel heat transfer dynamics and provides a signal proportional to the THERMAL POWER.

l The Average Power Range Monitor Simulated Thermal Power-High Function is required to be OPERABLE in MODE 1 when there is the possibility of generating excessive THERMAL POWER and potentially exceeding the SL applicable to high pressure and core flow conditions (MCPR SL). During MODES 2 and 5, other WRNM and APRM Functions provide protection for fuel cladding integrity.

I 2.c. Averaae Power Ranae Monitor Neutron Flux-Hiah l The Average Power Range Monitor Neutron Flux-High Function is capable of generating a trip signal to prevent fuel damage or excessive RCS pressure. For the overpressurization protection analysis of Reference 4, the I l Average Power Ranga Monitor Neutron Flux-High Function is i assumed to terminate the main steam isolation valve (MSIV) ,

closure event and, along with the safety / relief valves ]

(S/RVs), limit the peak reactor pressure vessel (RPV). '

pressure to less than the ASME Code limits. The control rod drop accident (CRDA) analysis (Ref. 5) takes credit for the

! Average Power Range Monitor Neutron Flux-High Function to terminate the CRDA. l I

i (continued)

PBAPS UNIT 3 8 3.3-10 Revision No.

Amndmnt No. 234

a RPS Instrumentation B 3.3.1.1 BASES l APPLICABLE 2.c. Averaae Power Ranae Monitor Neutron Flux-Hiah 1 SAFETY ANALYSES, (continued) l LCO, and APPLICABILITY The Allowable Value is based on the Analytical Limit assumed

) in the CRDA analysis.

l The Average Power Range Monitor Neutron Flux-High Function is required to be OPERABLE in MODE 1 where the potential consequences of the analyzed transients could result in the SLs (e.g., MCPR and RCS pressure) being exceeded. Although I l the Average Power Range Monitor Neutron Flux-High Function is assumed in the CRDA analysis, which is applicable in MODE 2, the Average Power Range Monitor Neutron Flux-High (Setdown) Function conservatively bounds the assumed trip and, together with the assumed WRNM trips, provides adequate protection. Therefore, the Average Power Range Monitor J. Neutron Flux-High Function is not required in MODE 2.

i l

l l

I (continued)

I PBAPS UNIT 3 B 3.3-11 Revision No.

kerd ent No. 234

! RPS Instrumentation B 3.3.1.1 BASES l

l APPLICABLE 2.d. Averaae Power Ranae Monitor-Inoo SAFETY ANALYSES, LCO, and Three of the four APRM channels are required to be OPERABLE APPLICABILITY for each of the APRM Functions. This Function (Inop)

(continued) provides assurance that the minimum number of APRM channels are OPERABLE.

For any APRM channel, any time its mode switch is not in the

" Operate" position, an APRM module required to issue a trip is unplugged, or the automatic self-test system detects a critical fault with the APRM channel, an Inop trip is sent to all four voter channels. Inop trips from two or more non-bypassed APRM channels result in a trip output from each i of the four voter channels to it's associated trip system. l This Function was not specifically credited in the accident analysis, but it is retained for the overal' redundancy and ,

diversity of the RPS as required by the NRC approved' licensing basis.

There is no Allowable Value for this function.

This Function is required to be OPERABLE in the MODES where l; the APRM Functions are required.

2.e. 2-Out-0f-4 Voter The 2-Out-0f-4 Voter Function provides the interface between the APRM Functions and the final RPS trip system logic. As such, it is required to be OPERABLE in the MODES where the APRM Functions are required and is recessary to support the safety analysis applicable to each of those Functions.

Therefore, the 2-Out-Of-4 Voter Function needs to be OPERABLE in MODES 1 and 2.

All four voter channels are required to be OPERABLE. Each voter channel includes self-diagnostic functions. If any veter channel detects a critical fault in its own processing, a trip is issued from that voter channel to the associated trip system.

There is no Allowable Value for this Function.

(continued)

PBAPS UNIT 3 8 3.3-12 Revision No.

Amnchent No. 234

7..

RPS Instrumentation 4 l

8 3.3.1.1 j BASES l APPLICABLE 14. RPS Channel Test Switch (continued)

SAFETY ANALYSES, LCO, and RPS Functions, described in Reference 9, were not affected APPLICABILITY by the difference in configuration, since each automatic RPS channel has a test switch which is functionally the same as the manual scram switches in the generic model. As such, the RPS Channel Test Switches are retained in the Technical Specifications.

There is no Allowable Value for this Function since the ;

channels are mechanically actuated based solely on the l position of the switches.

Four channels of RPS Channel Test Switch with two channels in each trip system arranged in a one-out-of-two logic are available and required to be OPERABLE in MODES 1 and 2, and in MODE 5 with any control rod withdrawn from a core cell containing one or more fuel assemblies, since these are the MODES and other specified conditions when control rods are withdrawn.

ACTIONS A Note has been provided to modify the ACTIONS related to RPS instrumentation channels. Section 1.3, Completion Times, specifies that once a Condition has been entered, subsequent divisions, subsystems, components, or variables expressed in the Condition, discovered to be inoperable or not within limits, will not result in separate entry into the Condition. Section 1.3 also specifies that Required Actions of the Condition continue to apply for each additional failure, with Completion Times based on initial entry into the Condition. However, the Required Actions for inoperable RPS instrumentation channels provide appropriate compensatory measures for separate inoperable channels. As such, a Note has been provided that allows separate Condition entry for each inoperable RPS instrumentation channel.

A.1 and A.2 Because of the diversity of sensors available to provide trip signals and the redundancy of the RPS design, an allowable out of service time of 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months has been shown to l be acceptable (Refs. 9, 12 & 13) to permit restoration of any inoperable channel to OPERABLE status. However, this out of service time is only acceptable provided the esociated (continued)

PBAPS UNIT 3 B 3.3-23 Revision No.

A1entent No. 234

I e l RPS Instrumentation B 3.3.1.1 l l

1 BASES I l'

ACTIONS .A.l'and A.2 (continued)

Function's inoperable channel is in one trip system and the

, Function still maintains RPS trip capability (refer to l Required Actions.B 1, B.2, and C.1 Bases). If the

inoperable channel cannot be restored to OPERABLE status l l

within.the allowable out of-service time, the channel or the l l associated trip system must be placed in the trippeti l condition per Required Actions A.1 and A.2. Placing the l inoperable channel _in trip (or the associated trip system in 1 trip) would conservatively compensate for the inoperability, I restore capability to accomodate a single failure, and allow operation to continue. Alternatively, if it is not i

desired to place the channel (or trip system) in trip (e.g.,

l as in the case where placing the inoperable channel in trip would result in a full scram), Condition,D must be entered and its Required Action taken.

As noted, Action A.2 is not applicable for APRM Functions l' 2.a. 2.b, 2.c, and 2.d. Inoperability of one required APRM channel affects both trip systems. For that condition,

' Required Action A.1 must be satisfied, and is the only action (other than restoring operability) that will restore capability to accomodate a single failure. Inoperability of more than one required APRM channel of the same trip function results in loss of trip capability and entry into Condition C, as well as entery into Condition A for each

channel.

B.1 and 8.2 Condition B exists when, for any one or more Functions, at least one required channel is inoperable in each trip system. In this condition, provided at least one channel per trip system is OPERABLE, the RPS still maintains trip capability for that Function, but cannot accomodate a j single failure in either trip system.

l Required Actions B.1 and B.2 limit the time the RPS scram L logic, for any Function, would not accomodate single l j failure in both trip systems (e.g., one-out-of-one and one-out-of-one arrangement for a typical four channel Function). The reduced reliability of this logic

'l arrangement was not evaluated in References 9,12 or 13 for the 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Completion Time. Within the 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months allowar.e, the associated Function will have all required channels l OPERABLE or in trip (or any combination) in one trip system.

(continued)

L PSAPS UNIT 3 8 3.3-24 Revision No.

kentent tb. 234

RPS Instrumentation B 3.3.1.1 BASES-l ACTIONS B.1 and B 2 (continued)

Completing one of these Required Actions restores RPS to a reliability leval equivalent to that evaluated in i

l. References 9, 12 or 13, which justified a 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months allowable !

out of service time as presented in Condition A. The trip i system in the more degraded state should be placed in trip l or, alternatively, all the inoperable channels in that trip l system should be placed in trip (e.g., a trip system with !

two inoperable channels could be in a mo.e degraded state i than a trip system with four inoperable channels if the two j inoperable channels are in the same Function while the four .

inoperable channels are all in different Functions). The !

decision of which trip system is in the more degraded state should be based on prudent judgment and take into account.

current plant conditions (i.e., what MODE the plant is in).

l If this action would result in a scram or RPT, it is permissible to place the other trip system or its inoperable channels in trip.

The 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months Com)letion Time is judged acceptable based on the ;

remaining capa)ility to trip, the diversity of the sensors '

available to provide the trip signals, the low probability ,

of extensive numbers of inoperabilities affecting all '

diverse Functions, and the low probability of an event requiring the initiation of a scram.

Alternately, if it is not desired to place the inoperable channels (or one trip system) in trip (e.g., as in the case where placing the inoperable channel or associated trip system in trip would result in a scram, Condition D must be entered and its Required Action taken.

As'noted, Condition B.is not applicable for APRM Functions 2.a, 2.b, 2.c, and 2.d. 'Inoperability of an APRM channel affects both trip systems and is not associated with a specific trip system as are the APRM 2-Out-Of-4 voter and other non-APRM channels for which Condition B applies. For an inoperable APRM channel, Required Action A.1 must be satisfied, and is the only action (other than restoring operability) that will restore capability to accommodate a single failure. Inoperability of more than one required l APRM channel results in loss of trip capability and entry l

into Condition C, as well as entry into Condition A for each channel. Because Condition A and C provide Required Actions that are appropriate for the inoperability of APRM Functions 2.a, 2.b, 2.c, and 2.d, and these functions are not associated with specific trip systems as are the APRM 2-Out-Of-4 voter and other non-APRM channels, Condition 8 does not apply.

(continued)

PBAPS UNIT 3 8 3.3-25 Revision No.

Anendwt No. 234

RPS Instrumentation B 3.3.1.1

, BASES ACTIONS U (continued)

Required Action C.1 is intended to ensure that appropriate actions are taken if multiple, inoperable, untripped l channels within the same trip system for the same Function 1 l result in an automatic Function, or two or more manual 1 Functions, not maintaining RPS trip capability. A Function is considered to be maintaining RPS trip capability when sufficient channels are OPERABLE or in trip (or the l associated trip system is in trip), such that both trip l systems will generate a trip signal from the given Function !

on a valid signal. For the typical Function with one-out- i

, of-two taken twice logic and the IRM and APRM Functions, this would require both trip systems to have one channel 0PERABLE or in trip (or the associated trip system in trip). ,

! For Function 5 (Main Steam Isolation Valve-Closure), this l l would require both trip systems to have each channel '

! associated with the MSIVs in three main steam lines (not i

l. necessarily the same main steam lines for both trip !

l systems)0PERABLE or in trip (or the associated trip system !

l in trip). For Function 8 (Turbine Stop Valve-Closure), j this would require both trip systems to have three channels, :

each OPERABLE or in trip (or the associated trip system in l trip). For Functions 12 (Reactor Mode Switen-Shutdown Position) and 13 (Manual Scram), this would require both trip systems to have one channel, each OPERABLE or in trip (or the associated trip system in trip).

The Completion Time is intended to allow the operator time to evaluate and repair any discovered inoperabilities. The 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Completion Time is acceptable because it minimizes risk while allowing time for restoration or tripping of channels.

M Required Action D.1 directs entry into the appropriate Condition referenced in Table 3.3.1.1-1. The applicable condition specified in the Table is Function and MODE or other specified condition dependent and may change as the Required Action of a previous Condition is completed. Each time an inoperable channel has not met any Required Action of Condition A, B, or C and the associated Completion Time has expired, Condition D will be entered for that channel and provides for transfer to the appropriate subsequent Condition.

(continued)

PBAPS UNIT 3 B 3.3-26 Revision No.

kendient tb. 234

,. .o-

,, RPS Instrumentation l B 3.3.1.1 BA3ES

~ ACTIONS E,1. F D nd G.l'

-(continued)

If the channel (s) is not restored to OPERABLE status or ,

-placed in trip (or the associated trip system placed in i trip).within the allowed Completion Time, the plant must be I placed in a MODE or other specified condition in which the l LCO does not apply. .The allowed Completion Times are reasonable, based on operating experience, to reach the specified condition from full power conditions in an orderly manner and without challenging plant systems. In addition, the Completion Time of Required Action E.1 is consistent with the Completion Time provided in LCO 3.2.2, " MINIMUM CRITICAL POWER RATIO (MCPR)."

M l

If the channel (s) is not restored to OPERABLE status or l placed in trip (or the associated trip system placed in j trip) within the allowed Completion Time, the plant must be i placed in a MODE or other specified condition in which the LC0 does not apply. This is done by immediately initiating action to. fully insert all insertable control rods in core l cells containing one or more fuel assemblies. Control rods in core cells containing no fuel assemblies do not affect i the reactivity of the core and are, therefore,.not required '

to be inserted. Action must continue until all insertable l control rods in core cells containing one or more fuel l assemblies are fully inserted.

SURVEILLANCE As noted at the beginning of the SRs, the SRs for each RPS REQUIREMENTS instrumentation Function are located in the SRs column of Table 3.3.1.1-1.

The Surveillances are modified by a Note to indicate that when a channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , provided the associated Function maintains RPS trip capability.- Upon completion of the Surveillance, or '

expiration of the 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months allowance, the channel must be returned to OPERABLE status or. the applicable Condition '

entered and Required Actions taken.' This Note is based on l the reliability analysis (Refs. 9, .12 & 13) assumption of the average time required to perform channel Surveillance.

That analysis demonstra'ed that the 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months testing allowance does not significantly reduce the probability that the RPS will trip when necessary.

(continued)

PBAPS UNIT.3 B 3.3-27 Revision No.

Amnchent No. 234

7 i

RPS Instrumentation B 3.3.1.1 BASES

~ SURVEILLANCE SR 3.3.1.1.1 REQUIREMENTS (continued) Performance of the CHANNEL CHECK once every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months ensures

'that a gross failure of instrumentation has not occurred. A CHANNEL . CHECK is normally a comparison of the parameter indicated on one channel to a similar parameter on other channel s. It is based on the assumption that instrument channels monitoring the same parameter should read approximately the same value. Significant deviations between instrument channels could be an indication of excessive instrument drift in one of the channels or something even more serious. A CHANNEL CHECK will detect i gross channel failure; thus, it is key to verifying the instrumentation continues to operate properly between each CHANNEL CALIBRATION.

Agreement criteria are determined by the plant staff' based on a combination of the channel instrument uncertaint'ies, including indication and readability. If a channel is outside the criteria, it may be an indication that the instrument has drifted outside its limit.

The Frequency is based upon operating experience that demonstrates channel failure is rare. The CHANNEL CHECK supplements less formal, but more frequent, checks of ,

channels during normal operational use of the displays I associated with the channels required by the LCO.

SR 3.3.1.1.2 To ensure that the APRMs are accurately indicating the true core average power, the APRMs are calibrated to the reactor power calculated from a heat balance. The Frequency of once per 7 days is based on minor changes in LPRM sensitivity, which could affect the APRM reading between performances of SR 3.3.1.1.8.

. (continued) i PBAPS UNIT 3 B 3.3-28 Revisinn No.

l ken &ent tb. 234

I l' .

RPS Instrumentation B 3.3.1.1 BASES l SURVEILLANCE SR 3.3.1.1.2 (continued)

REQUIREMENTS A restriction to satisfying this SR when < 25% RTP is l l

provided that requires the SR to be met only at 2 25% RTP because it is difficult to accurately maintain APRM indication of core THERMAL POWER consistent with a heat balance when < 25% RTP. At low power levels, a high degree of accuracy is unnecessary because of the large, inherent margin to thermal limits (MCPR and APLHGR). At 2 25% RTP, the Surveillance is required to have been satisfactorily performed within the last 7 days, in accordance with SR 3.0.2. A Note is provided which allows an increase in THERMAL POWER above 25% if the 7 day Frequency is not met per SR 3.0.2. In this event, the SR must be performed within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reaching or exceeding 25% RTP. Twelve hours.is based on operating experience and in consideration of providing a reasonable time in which ' ot complete the SR.

SR 3.3.1.1.3 l (Not Used.)

SR 3.3.1.1.4 A CHANNEL FUNCTIONAL TEST is performed on each required channel to ensure that the entire channel will perform the intended function. A Frequency of 7 days provides an acceptable level of system average availability over the Frequency and is based on the reliability analysis of References 9 and 10. (The RPS Channel Test Switch Function's CHANNEL FUNCTIONAL TEST Frequency was credited in the analysis to extend many automatic scram Functions' Frequencies.)

SR 3.3.1.1.5 and SR 3.3.1.1.6 A CHANNEL FUNCTIONAL TEST is performed on each required channel to ensure that the entire channel will perform the intended function. Any setpoint adjustment shall be made consistent with the assumptions of the current plant specific setpoint methodology.

_(. continued 1 PBAPS UNIT 3 8 3.3-29 Revision No.

kendaent tb. 234 l

t:

1 c ;

RPS Instrumentation B 3.3.1.1 BASES

. SURVEILLANCE 'SR 3.3.1.1.5 and SR 3.3.1.1.6 (continued)

REQUIREMENTS As noted, SR 3.3.1.1.5 is not required to be performed when

. entering MODE 2 from MODE 1, since testing of the MODE 2 required WRNM Functions cannot be performed in MODE 1 without utilizing jumpers, lifted leads, or movable links.

This allows entry into MODE 2 if the 31 day Frequency is not met per SR'3.0.2. In this event, the SR must be performed within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after entering MODE 2 from MODE 1. Twelve hours is based on operating experience and in consider.ation of providing a reasonable time in which to complete the SR.

L A frequency of 31 days provides an acceptable level of system average unavailability over the Frequency interval and is based on fixed incore detectors, overall reliability, .

l and self-monitoring features. 1 I

I SR 3.3.1.1.7 (Not Used.)

4 l

(continued)

U l

V .

l l

PBAPS UNIT 3 B 3.3-30 Revision No.

Anendnent bb. 234

E RPS Instrumentation B 3.3.1.1 BASES l SURVEILLANCE . SR' 3.3.1.1.8 s REQUIREMENTS j- (continued) LPRM gain settings. are determined from the local flux

-profiles meartred by the Traversing Incore Probe (TIP)

System. This establishes the relative local flux profile for appropriate representative input to the APRM System. 4 The-1000 MWD /T Frequency is based on operating experience with LPRM sensitivity changes.

l

! SR 3.3.1.1.9 and SR 3.3.1.1.14

-A CHANNEL FUNCTIONAL _ TEST is performed on each required l- channel to ensure that the entire channel will perform the i intended function. Any setpoint adjustment shall be L consistent with the assumptions of the current plant specific setpoint methodology. For Function 5, 7, and 8 L

channels, verification that the trip settings are less than or equal to the specified Allowable Value during the CHANNEL FUNCTIONAL TEST is not required since the channels consist l of mechanical switches and are not subject to drift. An exception to this are two of the Function 7 level switches which are not mechanical. These Scram Discharge Volume L (SOV) RPS switches (Fluid Components Inc.) are heat l- sensitive electronic level detectors which actuate by l- sensing a' difference in temperature. The temperature

detectors are permanently affixed within the scram discharge

. volume piping conservatively below the level (allowable value as measured in gallons) at which an RPS actuation f signal will occur. Since there is no drift involved w'th the physical location of these switches, verifying thi. trip settings 'are less than or equal to the specified allowable value during the CHANNEL FUNCTIONAL TEST is not required.

Additionally, historical calibration data has indicated that i

the FCI level switches have not exceeded their Allowable Value when tested.

(continued) l v

PBAPS UNIT 3 B 3.3-31 Revision No.

Amentent tb. 234 l

b

RPS Instrumentation B 3.3.1.1 BASES j SURVEILLANCE SR 3.3.1.1.9 and SR 3.3.1.1.14 (continued)

REQUIREMENTS In addition, Function 5 and 7 instruments are not accessible while it t is operating at power due to high radiation and the a !!ed indication instrumentation does not provide accurate indication of the trip setting. For the Function 9 channels, verification that the trip settings are less than or equal to the specified Allowable Value during the CHANNEL FUNCTIONAL TEST is not required since the instruments are not accessible while the unit is operating at. power due to high radiation and the installed indication instrumentation does not provided accurate indication of the trip setting. Waiver of these verifications for the above functions is considered acceptable since the magnituda of drift assumed in the setpoint calculation is based on a'24 month calibration interval. The 92 day Frequency of SR 3.3.1.1.9 is based on the reliability analysis of Reference 9.

The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the. potential for an unplanned transient if the Surveillance were performed with the reactor at power.

Operating experience has shown that these components will pass the Surveillance when performed at the 24 month Frequency.

l SR 3.3.1.1.10. SR 3.3.1.1.12. SR 3.3.1.1.15.

and SR 3.3.1.1.16 A CHANNEL CALIBRATION is a complete check of the instrument loop and the sensor. This test verifies that the channel ,

responds.to the measured parameter within the necessary -

range and accuracy. CHANNEL CALIBRATION leaves the channel adjusted to account for instrument drifts between successive calibrations, consistent with the current plant specific setpoint methodology. SR 3.3.1.1.16, however, is only a l calibration of the radiation detectors using a standard l radiation source.

l l As noted for SR 3.3.1.1.12, neutron detectors are excluded from CHANNEL CALIBRATION because they are passive devices,

! with minimal drift, and because of the difficulty of simulating a meaningful signal. Changes in

)

i (continued) l PBAPS UNIT 3 B 3.3-32 Revision No.

l kendnent No. 234 L

RPS Instrumentation B 3.3.1.1

-BASES

.l SURVEILLANCE SR 3.3.1.1.10. SR 3.3.1.1.12. SR 3.3.1.1.15.

REQUIREMENTS and SR 3.3.1.1.16 (continued) neutron detector sensitivity are compensated for by

' performing the 7 day calorimetric calibration (SR 3.3.1.1.2) and the 1000 MWD /T LPRM calibration against the TIPS (SR 3.3.1.1.8). A second note is provided for SR 3.3.1.1.12 that allows the WRNM SR to be performed within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months of entering MODE 2 from MODE 1. . Testing of the MODE 2 WRNM Functions cannot be performed in MODE 1 without utilizing jumpers, lifted leads or movable links. This Note allows I entry into MODE 2 from MODE 1, if the 24 month Frequency is not met per SR 3.0.2. Twelve hours is based on operating experience and in consideration of providing a reasonable time in which to complete the SR. For the APRM Simulated Thermal Power-liigh Function, SR 3.3.1.1.12 also includes calibrating the as'sociated recirculation loop flow channel. '

A third note is provided for SR 3.3.1.1.12 to include the recirculation flow transmitters that feed the APRMs as applied to Function 2.b. The Average Power Range Monitor Simulated Thermal Power-High Function uses the recirculation loop drive flows to vary the trip setpoint. This SR ensures that the recirculation flow transmitters that supply the recirculation flow signal to the APRMs respond to the measured recirculation flow within the necessary range and accuracy by use of a standard pressure source.

As noted for SR 3.3.1.1.10,. radiation detectors are excluded from CHANNEL CALIBRATION due to ALARA reasons (when the plant is operating, the radiation detectors are generally in a high radiation area; the steam tunnel). This exclusion is acceptable because the radiation detectors are passive devices, with minimal drift. The radiation detectors are calibrated in accordance with SR 3.3.1.1.16 on a 24 month Frequency.

The 92 day Frequency of SR 3.3.1.1.10 is conservative with respect to the magritude of equipment drift assumed in the l setpoint analysis. The Frequencies of SR 3.3.1.1.12, SR 3.3.1.1.15 and SR 3.3.1.1.16 are based upon the

, assumption of a 24 month calibration interval in the

determination of the magnitude of equipment drift in the l.

applicable setpoint analysis.

SR 3.3.1.1.11 A CHANNEL FUNCTIONAL TEST is performed on each required channe) to ensure that the entire channel will perform the (continued)

PBAPS UNIT.3 B 3.3-33 Revision No.

l Anenient No. 234 l

L L i

L RPS Instrumentation

l. B 3.3.1.1 i BASES SURVEILLANCE SR 3.3.1.1.11 (continued)

REQUIREMENTS intended function. For the APRM Functions, this test supplements _the automatic self-test functions that operate continuously in the APRM and voter channels. The APRM CHANNEL FUNCTIONAL TEST covers the APRM channels (including recirculation flow processing - applicable to Function 2.b only), the 2-Out-Of 4 voter channels, and the interface connections into the RPS trip systems from the voter channels. Any setpoint. adjustment shall be consistent with the assumptions of the current plant specific setpoint methodology. The 184 day Frequency of SR 3.3.1.1.11 is based on the reliability analyses of References 12 and 13.

(NOTE: The actual voting logic of the 2-Out-0f-4 Voter Function is tested as part of SR 3.3.1.1.17.)

A Note is provided for Function 2.a that requires this SR to be performed within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months of entering MODE 2 from MODE 1.

Testing of the MODE 2 APRM Function cannot be performed in MODE 1 withcut utilizing junipers or lifted leads. This Note allows entry into MODE 2 from MODE 1 if the associated frequency is not met per SR 3.0.2.

l A second Note is provided for Function 2.b that clarifies that the CHANNEL FUNCTIONAL TEST for Function 2.b includes testing of the recirculation flow processing electronics ,

excluding the flow transmitters.

SR 3.3.1.1.13 This SR ensures that scrams initiated from the Turbine Stop Valve-Closure and Turbine Control Valve Fast Closure, Trip 011 Pressure-Low Functions will not be inadvertently bypassed when THERMAL POWER is a 30% RTP. This involves calibration of the bypass channels. Adequate margins for the instrument setpoint methodologies are incorporated into the Allowable Value (s 29.4% RTP which is equivalent to s 138.4 psig as measured from turbine first stage pressure) and the actual setpoint. Because main turbine bypass flow can affect this setpoint nonconservatively (THERMAL POWER is i derived from turbine first stage pressure), the main turbine bypass valves must remain closed during the. calibration at THERMAL POWER 2 30% RTP to ensure that the calibration is i valid.

If any bypass channel's setpoint is nonconservative (i.e.,

the Functions are bypassed at 2 30% RTP, either due to open main turbine bypass valve (s) cr other reasons), then the (continued) l PBAPS UNIT 3 8 3.3-34 Revision No.

Aenwit tb. 234

RPS Instrumentation B 3.3.1.1 h

L CASES SURVEILLANCE. SR 3.3.1.1.13 (continued)

REQUIREMENTS.

affected Turbine Stop Valve-Closure and Turbine Control Valve Fast Closure, Trip 011 Pressure-Low Functions are considered inoperable. Alternatively, the bypass channel can be placed in the conservative condition (nonbypass). If l placed in the nonbypass condition, this SR is met and the l channel is considered OPERABLE.

The Frequency of 24 months is based on engineering judgment and reliability of the components. ;

SR 3.3.1.1.17 l l The LOGIC SYSTEM FUNCTIONAL TEST demonstrates the l

OPERABILITY of the required trip logic for a specific I channel.. The functional testing of control rods !

(LC0 3.1.3), and SDV vent and drain valves LC0 3.1.8),

overlaps this Surveillance to provide comple(te testing of the assumed safety function.

i The-24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for an un)lanned transient if the l

Surveillance were performed with t1e reactor at power. ,

Operating experience has shown that these components will pass the Surveillance when performed at the 24 month Frequency.

The LOGIC SYSTEM FUNCTIONAL TEST for APRM Function 2.e simulates APRM trip conditions at the 2-Out-0f-4 voter channel inputs to check all combinations of two tripped i l inputs to the 2-Out-0f-4 logic in the voter channels and L APRM related redundant RPS relays.

SR 3.3.1.1.18 This SR ensures that the individual channel response times are maintained less than or equal to the original design value. The RPS RESPONSE TIME acceptance criterion is incluoed in Reference 11.

RPS RESPONSE TIME tests are conducted on a 24 month Frequency. The 24 month Frequency is consistent with the PBAPS refueling cycle and is based upon plant operating experience, which shows that random failures of instrumentation components causing serious response time degradation, but not channel failure, are infrequent occurrences.

(continued) l-

-PBAPS' UNIT 3 B 3.3-35 Revision No.

Aitadvd No. 234 ;

L

l RPS Instrumentation j B 3.3.1.1 l BASES (continued) j l

~ REFERENCES 1. UFSAR, Section 7.2. I

2. UFSAR, Chapter 14.

l

3. NED0-32368, " Nuclear Measurement Analysis and Control !

Wide Range Neutron Monitoring System Licensing Report i for Peach Bottom Atomic Power Station, Units 2 and 3," {

November 1994. j

4. NEDC-32183P, " Power Rerate Safety Analysis Report for Peach Bottom 2 & 3," dated May 1993.

f j

5. UFSAR, Section 14.6.2. l

)

6. UFSAR, Section 14.5.4.

7. UFSAR, Section 14.5.1.

8. P. Check (NRC) letter to G._Lainas (NRC), "BWR Scram i Discharge System Safety Evaluation," December 1, 1980. j

9. NED0-30851-P-A , " Technical Specification Improvement l Analyses for BWR Reactor Protection System," l March 1988.

10. MDE-87-0485-1, " Technical Specification Improvement .

Analysis for the Reactor Protection System for Peach !

Bottom Atomic Power Station Units 2 and 3," October 1987.

11. UFSAR, Section 7.2.3.9.

12. NEDC-32410P-A, " Nuclear Measurement Analysis and Control Power Range Neutron Monitor (NUMAC PRNM)

Retrofit Plus Option III Stability Trip Function",

March 1995.

13. NEDC-32410P Supplement 1, " Nuclear Measurement Analysis and Control Power Range Neutron Monitor (NUMAC PRNM) Retrofit Plus Option III Stability Trip i Function, Supplement 1", November 1997.

PBAPS UNIT 3 B 3.3-36 Revision No.

Anentent No. 234

1

,, A i Control Rod Block Instrumentation B 3.3.2.1 I

B 3.3 , INSTRUMENTATION

. B_3.3.2.1 Control Rod Block Instrumentation BASES 1

1 BACKGROUND < Control rods provide the-primary means for control of reactivity changes. Control rod block instrumentation includes channel sensors, logic circuitry, switches, and relays that are designed to ensure that specified fuel design limits are not exceeded for postulated transients and accidents. During high power operation, the rod block monitor (RBM) provides protection for control rod withdrawal i error events. During low power operations, control rod I blocks from.the rod worth' minimizer (RWM) enforce specific control rod sequences designed to mitigate the consequences of the control rod drop accident (CRDA). During shutdown-conditions, control rod blocks from the Reactor Mode Switch-Shutdown Position Function ensure that all control rods remain inserted to prevent inadvertent criticalities.

The purpose of the RBM is to limit control rod withdrawal if localized neutron flux exceeds a predetermined setpoint during control' rod manipulations. It is assumed to function to block further control rod withdrawal to preclude a MCPR Safety Limit (SL) violation. The RBM supplies a trip signal to the Reactor Manual Control System (RMCS) to appropriately inhibit control rod withdrawe.1 during power operation above the low power range setpoint. The RBM has two channels, either of which can initiate a control rod block when the channel output exceeds the control rod block setpoint. One RBM channel inputs into one RMCS rod block circuit and the other RBM channel' inputs into the second RMCS rod block circuit. The RBM channel signal is generated by averaging a set.of local ~ power range monitor (LPRM) signals at various core heights surrounding the control rod being withdrawn. A signal from one of the four redundant average power range

, monitor-(APRM) channels supplies a reference signal for one of the RBM channels and a signal from another of the APRM channels supplies the reference signal to the second RBM channel. This reference signal is used to determine which RBM range se_tpoint (low,: intermediate, or high) is enabled.

o . If'the APRM is indicating less than the low power range s~

setpoint, the- RBM is automatically bypassed. The RBM is also. automatically bypassed if a peripheral control rod is selected (Ref.1). A rod. block signal is also generated if an RBM inoperable trip occurs, since this could indicate a problem with the RBM channel.

(continued).

PBAPS UNIT:3; B 3.3-46 Revision No.

Mendnent No. 234

Control Rod Block Instrumentation B 3.3.2.1 BASES l

BACKGROUND The inoperable trip will occur if, during the nulling I (continued) (normalization) sequence, the RBM channel fails to null or i too few LPRM inputs are available, if a critical self-test i fault has been detected, or the RBM instrument mode. switch I is moved to any position other than " Operate". A bypass time delay ensures that the normalized signal is passed to i the. trip logic in the appropriate time. The delay is ;

between the time the signal is nulled to the reference and !

the signal is passed to-the trip logic.

The purpose of the RWM is to control rod patterns during startup and shutdown, such that only specified control rod sequences and relative positions are allowed over the operating range from all control rods inserted to 10% RTP.

The sequences effectively limit the potential amount and rate of reactivity increase during a CRDA. Prescribed control rod sequences are stored in the RWM, which will initiate control rod withdrawal and insert blocks when the actual sequence deviates beyond allowances from the stored sequence. The RWM determines the actual sequence based position indication for each control rod. The RWM also uses feedwater flow and steam' flow signals to determine when the reactor power is above the preset power level at which the RWM is automatically bypassed (Ref. 2). The RWM is a single channel system that provides input into both RMCS rod block circuits.

With the reactor moda switch in the shutdown position, a control rod withdrawal block is applied to all control rods to ensure that the shutdown condition is maintained. This t

Function prevents inadvertent criticality as the result of a l control rod withdrawal during MODE 3 or 4, or during MODE 5 when the reactor mode switch is required to be in the shutdown position. The reactor mode switch has two channels, each inputting into a separate RMCS rod block circuit. A rod block in either RMCS circuit will provide a control rod block to all control rods.

APPLICABLE 1. Rod Block Monitor l SAFETY ANALYSES, LCO, and The RBM is designed to prevent violation of the MCPR l APPLICABILITY 'SL and the cladding 1% plastic strain fuel design limit that l may result from a single control rod withdrawal error (RWE) i event. The analytical methods and assumptions used in evaluating the RWE event are summarized in Reference 1. A (continued)

PBAPS 'AIT 3 B 3.3-47 Revision No.

AnenMent tb. 234 i

3 Control Rod Block Instrumentation B 3.3.2.1 BASES l

ACTIONS E.1 and E.2 (continued) i affect the reactivity of the core and are therefore not required to be: inserted. Action must continue until all insertable control rods in core cells containing one or more !

' fuel assemblies are fully inserted.

l-SURVEILLANCE As noted at the beginning of the SRs, the SRs for each REQUIREMENTS Control Rod Block instrumentation Function are found in the !

SRs column of Table 3.3.2.1-1.

1 The Surveillances are modified by a Note to indicate that when an-RBM channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed .

for up to S hours provided the associated Function ma'i,ntains control rod block capability. Upon completion of the Surveillance, or expiration of the 6 hour6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months allowance, the channel must be returned to OPERABLE status or the applicable Condition entered and Required Actions taken.

This Note is based on the reliability analysis (Refs. 8, 9,

& 10) assumptions of the average time required to perform channel surveillances. That analysis demon:trated that the 6' hour testing allowance does not significantly reduce the probability that a control rod block will be initiated when necessary.

SR 3.3.2.1.1 A CHANNEL FUNCTIONAL TEST is performed for each RBM channel to ensure that the entire channel will perform the intended function. Any setpoint adjustment shall be consistent with the assumptions of the current plant specific setpoint methodology. The Frequency of 184 days is based on reliability analyses (Refs. 7, 9 & 10).

1 (continued)

PBAPS UNIT 3- B 3.3-53 Revision No.

Amendaent No. 234

rn 1 l

i Control Rod Block Instrumentation l l B 3.3.2.1 ;

p l i

l MIRVEILLANCE I

REQUIREMENTS (continued) l

)

l 9

SR 3.3.2.1.2 and SR 3.3.2.1.3 l 1

A CHANNEL FUNCTIONAL TEST is performed for the RWM to ensure l that the entire system will perform the intended function. j The CHANNEL FUNCTIONAL TEST for the RWM is performed by .i attempting to withdraw a control rod not in compliance with j the prescribed sequence and verifying a control rod j blockoccurs. SR 3.3.2.1.2 is performed during a startup and )

SR 3.3.2.1.3 is performed during a shutdown (or power ;

reduction to s 10% RTP). As noted in the SRs, SR 3.3.2.1.2 !

is not required to be performed until I hour after any i control- rod .is withdrawn at s 10% RTP in MODE 2. As noted, SR 3.3.2.1.3 is not required to be performed until I hour after THERMAL POWER is s 10% RTP in MODE 1. This allows entry at s 10% RTP in MODE 2 for SR 3.3.2.1.2 and entry into 1 MODE 1 when THERMAL POWER is s 10% RTP for SR 3.3.2.1.3 to i' perform the required Surveillance if the 92 day Frequency is not met per SR 3.0.2. The I hour allowance is based on operating experience and in consideration of providing a reasonable time in which to complete the SRs. The Frequencies are based on reliability analysis (Ref. 7).

SR 3.3.2.1.4 The RBM setpoints are automatically varied as a function of !

power. Three Allowable Values are specified in the COLR, each within a specific power range. The power at which the ,

control rod block Allowable Values automatically change are '

based on the APRM signal's input to each RBM channel. Below the minimum power setpoint, the RBM is automatically i bypassed. These power Allowable Values must be verified using a simulated or actual signal periodically to be less than or equal to the specified values. If any power range setpoint is nonc.onservative, then the affected RBM channel is considered inoperable. Alternatively, the power range j (continued)

PBAPS UNIT 3 B 3.3154 Revision No.

Amntent No. 234

1

, Control Rod Block Instrumentation B 3.3.2.1 BASES SURVEILLANCE SR 3.3.2.1.4 (continued)

REQUIREMENTS channel can be placed in the conservative condition (i.e.,

encbling the proper RBM setpoint). If placed in this condition, the SR is met and the RBM channel is not ,

considered inoperable. As noted, neutron detectors are I excluded from the Surveillance because they are passive devices, with minimal drift, and because of the difficulty i of simulating a meaningful signal.

Neutron detectors are adequately tested in SR 3.3.1.1.2 and i SR 3.3.1.1.8. The 24 month Frequency is based on the actual trip setpoint methodology utilized for these channels.

SR 3. 3. 2.1J .

A CHANNEL CALIBRATION :s a complete check of the instrument loop and the sensor. This test verifies the channel responds to the measured parameter within the necessary range and accuracy. CHANNEL CALIBRATION leaves the channel adjusted to account for instrument drifts between successive calibrations consistent with the plant specific setpoint methodology.

As noted, neutron detectors are excluded from the CHANNEL CALIBRATION because they are passive devices, with minimal drift, 'and because of the difficulty of simulating a meaningful signal. Neutron detectors are adequately tested in SR 3.3.1.1.2 and SR 3.3.1.1.8. The Frequency is based l upon the assumption of a 24 month calibration interval in the determination of the magnitude of equipment drift in the setpoint analysis.

1 (continued)

PBAPS UNIT 3 B 3.3-55 Revision No.

kenchent No. 234

r o

l Control Rod Block Instrumentation B 3.3.2.1 BASES i -l SURVEILLANCE E

' REQUIREMENTS (continued) i SR 3.3.2.1.6 l The RWM is automatically bypassed when power is above a

specified value. The power level is determined from I

, feedwater flow and steam flow signals. The automatic bypast l setpoint must be verified periodically to be > 10% RTP. If i the RWM low power setpoint is nonconservative, then the RWM i is considered inoperable. Alternately, the low power l setpoint channel can be placed in the conservative condition (nonbypass). If placed in the nonbypassed condition, the SR ;

is met and the RWM is not considered inoperable. The '

Frequency is based on the trip setpoint methodology utilized for the low power setpoint channel.

i SR 3.3.2.1,7 l

l A CliANNEL FUNCTIO"#L TEST is performed for the Rea tor Mode Switch-Shutdown niettion Function to ensure that t?e entire channel will-perform the intended function. The CHANNEL FUNCTIONAL lEST for the Reactor Mode Switch-Shutdown Position function is performed by attempting to withdr o any l control rod with the reactor mode switch in the shutdown l position and verifying a control rod block occurs.

As noted in the SR, the Surveillance is not required to be performed until I hour after the reactor mode switch is in the shutdown position, since testing of this interlock with the reactor mode switch in any other position cannot be performed without using jumpers, lifted leads, or movable links. This allows entry into MODES 3 and 4 if the 24 nonth Frequency is not met per SR 3.0.2. The 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months allowance is j based on operating experience and in consideration of '

providing a reasonable time in which to complete the SR. J (continued)

PBAPS' UNIT 3 B 3.3-56 Revision No.

A e d m L No. 234

B Control Rod Block Instrumentation B 3.3.2.1 00SE3 FERENCES 7. NEDC-30851-P-A, " Technical Specification Improvement i (continued) Analysis for BWR Control Rod Block Instrumentation,"

October 1988.

8. GENE-770-06-1, " Addendum to Bases for Changes to Surveillance Test Intervals and Allowed Out-of-Service j Times for Selected Instrumentation Technical ;

Specifications," February 1991.

9. NEDC-32410P-A, " Nuclear Measurement Analysis and l Control Power Range Neutron Monitor (NUMAC PRNM)

Retrofit Plus Option III Stability Yrip Function",

March 1995.

10. NEDC-32410P Supplement 1, " Nuclear Measurement )

Analysis and Control Power Range Neutron Monitor I (NUMAC PRNM) Retrofit Plus Option III Stability Trip i Function, Supplement 1", November 1997. }

i l

i i

i

?

l l

i I i i

l PBAPS UNIT 3 B 3.3-58 Revision No.

konchent No. 234

l Recirculation Loops Operating B 3.4.1 BASES 1

APPLICABLE Plant specific LOCA and average power range monitor / rod l

SAFETY-ANALYSES block monitor Technical Specification / maximum extended load (continued) line limit analyses have been performed assuming only one operating recirculation loop. These analyses demonstrate l that, in the event of a LOCA caused by a pipe break in the ,

t operating recirculation loop, the Emergency Core Cooling l System response will provide adequate core cooling (Refs. 2, 3, and 4).

The transient analyses of Chapter 14 of the UFSAR have also been performed for single recirculation loop operation I

(Ref._5) and demonstrate sufficient flow coastdown ;

characteristics to maintain fuel thermal margins during the I abnormal operational transients analyzed provided the MCPR requirements are modified. During single recirculation loop operation, modification to the Reactor Protection System (RPS) average power range monitor (APRM) instrument setpoints is also required to account for the different relationships between recirculation drive flow and reactor ,

core flow. The MCPR limits and APLHGR limits (power-

~

dependent APLHGR multipliers, MAPFAC,, and flow-dependent APLHGR multipliers, MAPFAC,) for single loop operation are specified in the COLR. The APRM Simulated Thermal Power-High Allowable Value is in LC0 3.3.1.1, " Reactor Protection System (RPS) Instrumentation."

Safety analyses performed for UFSAR Chapter 14 implicitly assume core conditions are stable. However, at the high power / low flow corner of the power / flow map, an increased probability for limit cycle oscillations exists (Ref. 6) depending on combinations of operating conditions (e.g.,

power shape, bundle power, and bundle flow). Generic evaluations indicate that when regional power oscillations become detectable on the APRMs, the safety margin may be insufficient under some operating conditions to ensure actions taken to respond to the APRMs signals would prevent violation of the MCPR Safety Limit (Ref. 7). NRC Generic Letter 86-02 (Ref. 8) addressed stability calculation methodology and stated that due to uncertainties, 10 CFR 50, Appendix A, General Design Criteria (GDC) 10 and 12 could not be met using analyt's procedures on a BWR 4 design.

However, Reference 8 concluded that operating limitations which provide for the detection (by monitoring neutron flux noise levels) and suppression of flux oscillations in operating regions of potential instability consistent with (continued)

PBAPS UNIT B 3.4-3 Revision No.

Arentent No. 234

L l

l

' Recirculation Loops Operating ;

B 3.4.1 l BASES

]

l LC0 assumptions of the LOCA analysis are satisfied. In {

addition, the core flow expressed as a function of THERMAL )

POWER must be in the " Unrestricted" Region of !

Figure 3.4.1-1, " THERMAL POWER Versus Core Flow Stability ;

Regions." Alternatively, with only one recirculation loop i in operation, modifications to the required APLHGR limits i (power- and flow-dependent APLHGR multipliers, MAPFAC, and :

MAPFAC,, respectively of LC0 3.2.1, " AVERAGE PLANAR LINEAR l HEAT GENERATION RATE (APLHGR)"), MCPR limits (LC0 3.2.2, '

" MINIMUM CRITICAL POWER RATIO (MCPR)") and APRM Simulated j Thermal Power-High Allowable Value (LC0 3.3.1.1) must be j l applied to allow continued operation consistent with the l assumptions of References 5 and 6. j The LC0 is modified by a Note which allows up to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months before having to put in effect the required modifications to . j required limits after a change in the reactor operatil!g i conditions from two recirculation loops operating to single recirculation loop operation. If the required limits are i not'in compliance with the applicable requirements at the i end of this period, the associated equipment must be declared inoperable or the limits "not satisfied," and the ACTIONS required by nonconformance with the applicable specifications implemented. This time is provided due to the need to stabilize operation with one recirculation loop, including the procedural steps necessary to limit flow in the operating loop, limit total THERMAL POWER, monitor for !

excessive APRM and local power range monitor (LPRM) neutron flux noise levels; and the complexity and detail required to fully implement and confirm the required limit modifications.

APPLICABILITY In MODES 1 and 2, requirements for operation of the Reactor Coolant Recirculation System are necessary since there is considerable energy in the reactor core and the limiting design basis transients and accidents are assumed to occur.

In MODES 3, 4, and 5, the consequences of an accident are reduced and the coastdown characteristics of the recirculation loops are not important.

(continued) l PBAPS UNIT 3 B 3.4-5 Revision No.

Anendmnt No. 234

, l Recirculation loops Operating i B 3.4.1 l BASES l ACTIONS M With one or two recirculation loops in operation with core flow as a function of THERMAL POWER in the " Restricted" Region of Figure 3.4.1-1, the plant is operating in a region where the potential for thermal hydraulic instability exists. In order to assure sufficient margin is provided for operator response to detect and suppress potential limit l cycle oscillations, APRM and local power range monitor (LPRM) neutron flux noise levels must be periodically monitored and verified to be s 4% and s 3 times baseline noise levels. Detector levels A and C of one LPRM string per core quadrant plus detectors A and C of one LPRM string in the center of the core shall be monitored. A minimum of l three APRMs shall also be monitored. The Completion Times of this verification (within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months thereafter and within I hour after completion of any THERMAL POWER increase 2 5% RATED THERMAL POWER) are acceptable for ensuring potential limit cycle oscillations are detected to allow operator response to suppress the oscillation. These Completion Times were developed considering the operator's inherent knowledge of reactor status and sensitivity to potential thermal hydraulic instabilities when operating in this condition.

M With the Required Action and associated Completion Time of Condition A not met, sufficient margin may not be available for operator response to suppress potential limit cycle oscillations since APRM or LPRM neutron flux noise levels may be > 4% and > 3 times baseline noise levels. As a result, action must be immediately initiated to restore noise levels to within required limits. The 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Completion Time for restoring APRM and LPRM neutron flux noise levels to within required limits is acceptable because it minimizes risk while allowing time for restoration before subjecting the plant to transients associated with shutdown.

(continuedj.

s PBAPS UNIT 3 8 3.4 6 Revision No.

Merdmnt tb. 234

SDM Test-Refueling B 3.10.8 BASES APPLICABLE CRDA analyses assume that the reactor operator follows SAFETY ANALYSES prescribed withdrawal sequences. For SDM tests performed (continued) within these defined sequences, the analyses of References 1 and 2 are applicable. However, for some sequences developed for the SDM testing, the control rod patterns assumed in the safety analyses of References 1 and 2 may not be met.

Therefore, special CRDA analyses, performed in accordance with an NRC approved methodology, are required to demonstrate the SDM test sequence will not result in unacceptable consequences should a CRDA occur during the testing. For the purpose of this test, the protection provided by the normally required P'0DE 5 applicable LCOs, in addition to the requirements of this LCO, will maintain normal test operations as well as costulated accidents ,

within the bounds of the appropriate safety analyses I (Refs. 1,and 2). In addition to the added requirements for l the RWM, WRNM, APRM, and control rod coupling, the notch out I mode is specified for out of sequence withdrawals.

Requiring the notch out mode limits withdrawal steps to a single notch, which limits inserted reactivity, and allows adequate monitoring of changes in neutron flux, which may occur during the test.

As described in LC0 3.0.7, compliance with Special Operations LCOs is optional, and therefore, no criteria of the NRC Policy Statement apply. Special Operations LCOs provide flexibility to perform certain operations by appropriately modifying requirements of other LCOs. A discussion of the criteria satisfied for the other LCOs is provided in their respective Bases.

LC0 As described in LC0 3.0.7, compliance with this Special Operations LC0 is optional. SDM tests may be performed while in MODE 2, in accordance with Table 1.1-1, without meeting this Special Operations LC0 or its ACTIONS. For SDM tests performed while in MODE 5, additional requirements must be met to ensure that adequate protection against potential reactivity excursions is available. To provide additional scram protection beyond the normally required WRNMs, the APRMs are also required to be OPERABLE (LC0 l 3.3.1.1, Functions 2a, 2.d and 2e) as though the reactor were in MODE 2. Because multiple control rods will be withdrawn and the reactor will potentially become critical, the approved control rod withdrawal sequence must be enforced by the RWM (LC0 3.3.2.1, Function 2, MODE 2), or must be verified by a (continued)

PBAPS UNIT 3 B 3.10-32 Revision No.

kentent tb. 234

l SDM Test-Refueling B 3.10.8 BASES (continued)

SURVEILLANCE SR 3.10.8.1. SR 3.10.8.2. and SR 3.10.8.3 REQUIREMENTS ,

l LC0 3.3.1.1, Functions 2a, 2.d and 2e, made applicable in d this Special Operations LCO, are required to have their Surveillances met to establish that this Special Operations 1 LC0 is being met. However, the control rod withdrawal l sequences during the SDM tests may be enforced by the RWM I (LC0 3.3.2.1, Function 2, MODE 2 requirements) or by a second licensed operator or other qualified member of the technical staff. As noted, either the applicable SRs for -

the RWM (LCO 3.3.2.1) must be satisfied according to the applicable Frequencies (SR 3.10.8.2), or the proper movement I of control rods must be verified (SR 3.10.8.3). This latter i verification (i.e., SR 3.10.8.3) must be performed during !

control rod movement to prevent deviations from the !

specified sequence. These surveillances provide adequate i assurance that the specified test sequence is being followed. l SR 3.10.8 4 Periodic verification of the administrative controls established by this LC0 will ensure that the reactor is operated within the bounds of the safety analysis. The 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Frequency is intended to provide appropriate assurance that each operating shift is aware of and verifies compliance with these Special Operations LC0 requirements.

SR 3.10.8.5 Coupling verification is performed to ensure the control rod is connected to the control rod drive mechanism and will perform its intended function when necessary. The verification is required to be performed any time a control rod is withdrawn to the " full out" notch position, or prior to declaring the control rod OPERABLE after work on the control rod or CRD System that could affect coupling. This i Frequency is acceptable, considering the low probability that a control rod will become uncoupled when it is not being moved as well as operating experience related to uncoupling events.

(cor.tinued) t PBAPS UNIT 3 8 3.10-35 Revision No.

l kenchent No. 234

ML20217K976

Text

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