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Proposed Tech Specs,Revising Tech Spec Associated W/Reactor Protection Sys Instrumentation
	ML13331B109
Person / Time
Site:	San Onofre
Issue date:	12/29/1988
From:	; SOUTHERN CALIFORNIA EDISON CO.
To:	;
Shared Package
ML13331B107	List: ML13331B106; ML13331B108; ML13331B109;
References
	NUDOCS 8901030285
	Download: ML13331B109 (16)
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ATTACHMENT 2 PROPOSED TECHNICAL SPECIFICATIONS n-00020 8910:30285 SS31229 PDR ADOClK 05

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TABLE 3.5.1-1 REACTOR TRIP SYSTEM INSTRUMENTATION MINIMUM TOTAL NO.

CHANNELS CHANNELS APPLICABLE FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERABLE MODES ACTION

1. Manual Reactor Trip 2

1 2

1, 2 1

2 1

2 3*, 4*, 5*

7

2. Power Range, Neutron Flux 4

2 3

1, 2 2#

3. Power Range, Neutron Flux 4

1**

4 1, 2 28#

Dropped Rod Rod Stop

4. Intermediate Range, 2

1 2

1###, 2 3

Neutron Flux

5. Source Range, Neutron Flux A. Startup 2

1**

2 2##

4 B. Shutdown 2

1**

2 3*, 4*, 5*

7 C. Shutdown 2

0 1

3, 4 and 5 5

6. NIS Coincidentor Logic 2

1 2

1, 2 29 3*, 4*, 5*

7

7. Pressurizer Variable 3

2 2

l####

2#

Low Pressure Calculator

8. Pressurizer Pressure 3

2 2

1, 2 2#,***

9. Pressurizer Level 3

2 2

1 2#

10.

Reactor Coolant Flow A. Single Loop 1/loop 1/loop in any 1/loop in each 1

6#

(Above 50% of Full Power) operating loop operating loop B. Two Loops 1/loop 1/loop in two 1/loop in each l####

6#

(Below 50% of Full Power) operating loops operating loop

11.

Steam/Feedwater Flow Mismatch 3

2 2

1, 2 2#

TABLE 3.5.1-1 (Continued)

REACTOR TRIP SYSTEM INSTRUMENTATION MINIMUM TOTAL NO.

CHANNELS CHANNELS APPLICABLE FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERABLE MODES ACTION

12.

Turbine Trip A. Low Fluid Oil Pressure 3

2 2

1####

2#

13.

Reactor Trip Breakers 2

1 2

1, 2 30 2

1 2

3*, 4*, 5*

7

14.

Sequencer Input to 2

1 2

1, 2 29***

Reactor Trip

TABLE 3.5.1-1 (Continued)

TABLE NOTATION With the reactor trip system breakers in the closed position, the control rod drive system capable of rod withdrawal.

A "TRIP" will stop all rod withdrawal.

Comply with the provisions of Specification 3.5.5 for any portion of the channel required to be OPERABLE by Specification 3.5.5.

The provisions of Specification 3.0.4 are not applicable.

Below the Source Range High Voltage Cutoff Setpoint.

1. 1. Below the P-7 (At Power Reactor Trip Defeat) Setpoint.

1. 1. 1. Above the P-7 (At Power Reactor Trip Defeat) Setpoint.

ACTION STATEMENTS ACTION 1 - With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, restore the inoperable channel to OPERABLE status within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months or be in HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

ACTION 2 - With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed provided the following conditions are satisfied:

a. The inoperable channel is placed in the tripped condition within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. The Minimum Channels OPERABLE requirement is met; however, the inoperable channel may be returned to the untripped condition for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for surveillance testing of other channels per Specification 4.1.

ACTION 3 -

With the number of channels OPERABLE one less than the Minimum Channels OPERABLE requirement and with the THERMAL POWER level:

a. Below the Source Range High Voltage Cutoff Setpoint, restore the inoperable channel to OPERABLE status prior to increasing THERMAL POWER above the Source Range High Voltage Cutoff Setpoint.

b. Above the Source Range High Voltage Cutoff Setpoint but below 10 percent of RATED THERMAL POWER, restore the inoperable channel to OPERABLE status prior to increasing THERMAL POWER above 10 percent of RATED THERMAL POWER.

However, one channel may be bypassed for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for surveillance testing per Specification 4.1, provided the other channel is OPERABLE.

ACTION 4 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement suspend all operations involving positive reactivity changes.

TABLE 3.5.1-1 (Continued)

TABLE NOTATION ACTION 5 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, verify compliance with the SHUTDOWN MARGIN requirements of Specification 3.5.2 as applicable, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter.

ACTION 6 -

With the number of OPERABLE channels one less than the Total Number of Channels, STARTUP and/or POWER OPERATION may proceed until performance of the next required OPERATIONAL TEST provided the inoperable channel is placed in the tripped condition within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

ACTION 7 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, restore the inoperable channel to OPERABLE status within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months or open the reactor trip breakers within the next hour.

ACTION 28 -

With the number of OPERABLE channels less than the Minimum Channels OPERABLE requirement, within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months reduce THERMAL POWER such that Tave is less than or equal to 551.5 degrees F, and place the rod control system in manual mode.

ACTION 29 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; however, one channel may be removed from service for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for surveillance testing per Specification 4.1.1, provided the other channel is OPERABLE.

ACTION 30 -

With the number of OPERABLE channels one less than the Minimum Channels OPERABLE requirement, be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and apply ACTION 7.

MJT:8346F

TABLE 4.1.1 REACTOR TRIP SYSTEM INSTRUMENTATION SURVEILLANCE REQUIREMENTS TRIP ACTUATING DEVICE CHANNEL CHANNEL CHANNEL OPERATIONAL ACTUATION FUNCTIONAL UNIT CHECK CALIBRATION TEST TEST LOGIC TEST

1. Manual Reactor Trip N.A.

N.A.

R (8)

N.A.

2. Power Range, Neutron Flux S

D (2,3),

S/U (1),

N.A.

R (3,4)

Q (10)

3. Power Range, Neutron Flux, N.A.

N.A.

Q (10)

N.A.

Dropped Rod Rod Stop

4. Intermediate Range, S

R (3,4)

S/U (1),

N.A.

Neutron Flux Q (10)

5. Source Range, Neutron Flux S

R (3)

S/U (1),

N.A.

Q (10)

6.

NIS Coincidentor Logic N.A.

N.A.

M (5)

7. Pressurizer Variable Low S

R Q (10)

N.A.

Pressure Calculator

8. Pressurizer Pressure S (12)

R Q (10,11)

N.A.

9. Pressurizer Level S (12)

R Q (10)

N.A.

10.

Reactor Coolant Flow S (12)

R Q

N.A.

11.

Steam/Feedwater Flow S (12)

R Q (10)

N.A.

Mismatch

12.

Turbine Trip-Low Fluid N.A.

N.A.

S/U (1,6)

N.A.

Oil Pressure

13.

Reactor Trip Breakers N.A.

N.A.

R (9)

N.A.

14.

Sequencer Input to N.A.

N.A.

R (11)

N.A.

Reactor Trip

TABLE 4.1.1 (Continued)

TABLE NOTATION (1) -

If not performed in previous 31 days.

(2) -

Heat balance only, above 15% of RATED THERMAL POWER. Adjust channel if absolute difference greater than 2 percent.

(3) -

Neutron detectors may be excluded from CHANNEL CALIBRATION.

(4) -

The provisions of Specification 4.0.4 are not applicable for entry into MODE 2 or 1.

(5) -

Each train shall be tested at least every 62 days on a STAGGERED TEST BASIS.

(6) -

Setpoint verification is not applicable.

(7) -

If not performed in the previous 92 days.

(8) -

The TRIP ACTUATING DEVICE OPERATIONAL TEST shall independently verify the OPERABILITY of the undervoltage and shunt trip circuits for the Manual Reactor Trip Function.

(9) -

The TRIP ACTUATING DEVICE OPERATIONAL TEST shall independently verify the OPERABILITY of the undervoltage and shunt trip attachments of the Reactor Trip Breakers.

(10) -

Each channel shall be tested at least every 92 days on a STAGGERED TEST BASIS.

(11) -

Comply with the surveillance requirements of Specification 4.1.4 for any portion of the channel required to be OPERABLE by Specification 3.5.5.

(12) -

Monitor parameter not setpoint (i.e., check pressurizer pressure not pressurizer high pressure trip).

ATTACHMENT 3 SCE Positions to NRC Imposed Conditions

NRC IMPOSED CONDITIONS The NRC has imposed five conditions on utilities seeking to implement the technical specification changes approved generically as a result of their review of WCAP-10271.

These conditions must be addressed by each utility in the plant specific technical specification change request. SCE's position is provided for each condition.

1. The first condition requires the use of a staggered test plan for the RPS channels changed to the quarterly test frequency as stated by NRC in the safety evaluation for WCAP-10271:

System unavailability, or probability of failure due to common cause, is proportional to the time between staggered tests.

Therefore, if the test interval is expanded, the failure probability will increase. A staggered plan which "spreads" the channel testing over the quarter rather than "concentrating" the channel testing would reduce the potential for common cause function failure and at the same time still accomplish the goals set forth by the Owners Group. Accordingly, the staff's acceptance of less frequent surveillance is contingent on the implementation of a staggered test plan.

SCE currently has a staggered test plan which will satisfy the NRC condition of acceptance contained in the SER. Under this plan one channel of a four channel function must be tested every three weeks such

4 0

-2 that all channels are tested each quarter. One channel of a three channel function must be tested every month. One channel of a two channel function must be tested every six weeks.

The staggered testing requirement was made part of the technical specifications for surveillance testing of certain non-RPS instrument channels in 1984. This testing requirement will be incorporated in the RPS surveillance schedule table. The RPS surveillance table has been modified to reference a footnote wherever quarterly testing is specified.

2. The second condition requires that plant procedures require a common mode evaluation for failure in the RPS channels changed to the quarterly test frequency and additional testing for plausible common cause failures. As stated by NRC in the safety evaluation for WCAP-10271:

The staff's evaluation of RPS unavailability assumed that common cause failures would be identified during testing. The staff's assumption was that the identification would occur because all the additional channels in a function would be tested whenever one channel failed a test. However, from a practical standpoint, there are several kinds of failures which the staff does not regard as common cause failures, e.g., instrument drift and failure of power to a single channel.

Additional testing is not necessary for these failures or other failures if the cause of those failures can be evaluated and shown not to affect multiple channels. In order to

-3 validate the staff's underlying assumption, the staff's acceptance of less frequent surveillance is contingent on implementation of procedures to identify common cause failures and to test the other channels which may be affected by the common cause.

SCE confirms the existence of procedures which require the evaluation of a failure of any RPS channel on the quarterly test program to determine if that failure could be a common cause failure. These procedures satisfy the NRC condition of acceptance contained in the SER. The plant procedure requires that the appropriate remedial action, such as additional testing of the other channels in that function, occur if the failure is determined to be a plausible common cause failure. As noted above, failures such as instrument drift and power supply failures to a single channel are not considered common cause failures. Additional testing is not required for these types of failures. Additionally, failures of the sort that are "announced" through control room alarms or annunciation or through other readily observed means need not be considered to be plausible common cause problems and do not require additional testing. Any additional testing that is performed will be consistent with the types of problems to be found.

For example, if the failure cannot be detected by standard channel tests, testing other than the standard channel test should be performed.

-4 In making a determination about common cause, appropriate personnel consider the nature of the failure, the experience of their equipment, and industry experience in general.

For example, a transistor failure may be considered a plausible common mode failure because that type of transistor is used in other circuits. However, this may not be a plausible common mode failure if similar failures in equipment have been rare and no significant problems have been identified through the industry experience review program.

Plausible common cause problems will be identified only where failure can be shown to be attributable to processes which are common to redundant equipment. That is, the underlying failure mechanism must be shown to have had the potential for causing failure in redundant channels.

Failures and/or failure mechanisms which do not satisfy this criteria are not considered as a plausible common cause problem. Some examples of plausible common cause problems are presented. A simple transistor failure that has no distinguishing characteristics may be considered a random failure. However, if the failure is attributed to a temperature excursion in the rack cabinet, it may be considered a plausible common cause problem. In this case testing of the circuits affected by the temperature excursion may be warranted. The failure may also be considered a plausible common cause problem if the failure was attributed to an improper test method that damaged components and that damage can only be found by subsequent testing. In this case a review of the test records may indicate other channels subjected to the improper test method that warrant additional testing.

p0 0

-5 The intent of this condition is not to judge every failure as a potential common cause problem. Rather, the intent is to make the utility conscious of common mode problems and to take additional action when a plausible common mode problem is identified. This condition need not require supplemental experience review when a channel problem is identified. The normal industry experience review programs currently in place are sufficient to identify problems that may contain elements of common cause.

3. The third condition requires installed hardware capability for testing in the bypass mode. As stated by the NRC in the safety evaluation for WCAP-10271:

Testing of the RPS analog channels in the bypassed condition by use of temporary jumpers or by lifting leads is not acceptable. The chance of personnel errors leaving a number of channels in the bypassed condition would be too large for the routine use of such methods. Therefore, licensees choosing this option to perform routine channel testing in the bypass mode should ensure that the plant design allows testing in bypass without lifting leads or installing temporary jumpers. The staff's acceptance of this option is contingent on confirmation of this capability.

-6 San Onofre Unit 1 does not have the capability to test all of the RPS analog channels in the bypassed condition without reliance on lifted leads or jumpers. It is SCE's intention to make hardware changes in the future to provide this testing capability for some of these RPS channels. Currently, however, routine testing of RPS analog channels will not be performed in the bypassed condition for channels that require lifting of leads or jumpers. Once the plant modifications are made, routine testing of the channels with a bypass switch will be performed with the channel in bypass.

4. The fourth condition involves channels that provide input to both the RPS and the engineered safety feature actuation system (ESFAS).

As stated by the NRC in the safety evaluation for WCAP-10271:

In order to avoid confusion in plant technical specifications regarding such dual function channels, the staff concludes that either (1) the channels should not be changed in the RPS tables until the ESFAS review is finished or (2) cautionary notes in the RPS tables should refer to the more stringent ESFAS requirements.

The proposed changes to the RPS technical specifications include appropriate cautionary statements to the action statements referencing the more stringent requirements for the ESFAS channels. Administrative controls will be established to ensure that the more restrictive requirements are observed.

-7 For those channels which have both RPS and ESFAS functions all failures and testing will either involve parts of the channel that are common to both the ESFAS and RPS function or they will be limited to one or the other. Testing and failures in the common part of the channels will follow the more restrictive technical specification requirements for the ESFAS equipment. Testing and failures that are limited to the RPS portion of the channel will follow the relaxed requirements.

For example, a failure of a RPS bistable card would be subject to the relaxed RPS portion of the system. On the other hand, a failure of the transmitter that provides a signal to both RPS and ESFAS bistables would be subject to the more restrictive ESFAS action time. Also, in cases where a separate bistable card is used for RPS and ESFAS setpoints, the RPS card may be tested on the relaxed RPS schedule.

5. The fifth condition addresses setpoint drift. As stated by the NRC in the safety evaluation for WCAP-10271:

Based on review of previous Westinghouse topical reports, the staff notes that margin is included in the channel setpoint determination to account for possible instrument drift over a one month surveillance interval.

Accordingly, the staff's acceptance is contingent on confirmation that the instrument setpoint methodology includes sufficient adjustments to offset the drift anticipated as a result of less frequent surveillance.

-8 The setpoint methodology allowance for drift is chosen to conservatively bound any anticipated drift over a one month surveillance interval.

SCE does not have sufficient data to conclude that the setpoint allowance also conservatively bounds any anticipated drift over a quarterly surveillance interval.

SCE will review plant specific instrument calibration records for these channels to determine equipment performance A review of the "as found" and "as left" data over a twelve month period should provide sufficient information to address the adequacy of the existing setpoints and allowable values.

Changes to the setpoints and allowable values will be made as necessary after the data has been reviewed.

MJT:8337F

ML13331B109

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