ML19332F748

Proposed Tech Specs Re Limiting Condition for Operation & Surveillance Requirements for Ac Sources

ML19332F748
Person / Time
Site:	Summer
Issue date:	12/11/1989
From:	SOUTH CAROLINA ELECTRIC & GAS CO.
To:
Shared Package
ML19332F746	List: ML19332F745 ML19332F748
References
NUDOCS 8912180210
Download: ML19332F748 (9)

Text

3/4.8 ELECTRICAL POWER SYSTEMS

< 3/4.8.1 A.C. SOURCES OPERATING LIM 111NG CONDITION FOR OPERA 110N 1

3.8.1.1 As a minimum, the following A.C. electrical power sources shall be.

OPERABLE:

a. Two physically independent circuits between the of fsite transmission ,

network and the onsite Class 1E distribution system, and

b. Two separate and independent Emergency Diesel Generators (EDG), each with:

1. A separate day fuel tank containing a minimum volume of 300

.gallo'ns of fuel, ,

2. A separate fuel storage system containing a minimum volume of 47 g -42f00- gallons of f uel, and

'3. A separate fuel transfer pump.

APPLICABILITY: N0 DES 1, 2, 3 and 4.

ACTION:

a. With one of f site circuit of 3.8.1.1.a inoperable:

1. Demonstrate the OPERABillTY of the remaining offsite A.C.

sources by performing Surveillance Requirement 4.8.1.1.1.a within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and

2. If either CDG has not been successfully tested within the past 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, demonstrate its OPERABILITY by performing Surveillance Requirement 4.8.1.1.2.a.3 separately for each such EDG within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> unless the diesel is already opercting, and

3. Restore the offsite circuit to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at-least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOW within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

b. With oneEDG of 3.8.1.1.b inoperable:

1. Demonstrate the OPERABILITY of the A.C. offsite sources by l performing Surveillance Requirement 4.3.1.1.1.a within I hour l^ and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and

2. If the EDG became inoperable due to any cause other than preplanned preventive maintenance or testing, demor. strate the i OPERABILITY of t5c remaining EDG by perforn,~ng Surveillance Requirements 4 3.1.1.2.a.3 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> *, and

• This test is required to be completed regardless of when the inoperable EDG

is restored to OPERABILITY.

l AMENDMENT NO.77 SUMMER - UNIT 1 3/4 8-1 08912180210 891211  ?

T  ;PDR ADOCK 05000395

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~ ' ELECTRICAL POWER SYSTEMS

,e A.C. SOURCES SHUlDOWN '

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-LIMIT!.NC. CON 0lTION'FOR OPERATION 3.8.1.2 As a minimum, the following A.C. electrical power sources shall be OPERABLE:

a.

One circuit Class.1E betweensystem, distribution the offsite and transmission network and the onsite '

b. One diesel generator

• with:

1. , A. day fuel tank coataining a minimum volume of 300 gallons of fuel, ,

2. 4 A fuel storage system containing a mit.imum volume of -30,000=

gallons of fuel, and 33 2sst) i

3. A fuel transfer pump.

l APPLICABILITY: MODES 5 and 6. I ACTION: i With less than the above minimum required A.C. electrical power sources 0PERABLE, immediately suspend all operations involving CORE ALTERATIONS positive reactivity changes, movement of irradiated fuel, or crane-operation with loads over the fuel storage pool. In addition, when in MODE S with the Reactor Coolant loops

'l not filled, or in MODE 6 with the water level less than 23 feet above the i reactor-vessel flange, immediately initiate corrective action to restore the required sources to OPERABLE status as soon as possible.

SURVEILLANCE REQUIREMENTS

4. 8.1. 2 The above required A.C. electrical power sources snall be demonstrated OPERABLE by the performance of each of the Surveillance Requirements of 4.8.1.1.1,-

4.8.1.1. 2 (with the exception of 4. 8.1.1. 2. a.4) and 4. 8.1.1. 3.

• ESF load sequencer may be deenergized in Modes 5 and 6 provided that the loss of voltage and degraded voltage relays are disabled.

SUMMER - UNIT 1 3/4 8-8 AMENDMENT NO. 77

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. 3/4.8 ElEC1RICAL POWER _SYSl[MS I 4"

BASES-3/4.8.1 3/4.8.2 AND 3/4.8.3 A.C. SOURCES, D.C. SOUPEES AND ONSITE POWER DT5T m u,TT W 3Y5TUIS The OPERABILITY of the A.C. and 0.C power sources and associated i

distribution systems during operation ensures that suf ficient power will be available to supply the safety related equipment required for 1) the safe i shutdown of the f acility and 2) the mitigation and control of accident condi-tions within the facility. The minimum specified independent and redundant A.C. and D.C. power sources and distribution systems satisfy the requirements of General Design Criterion 17 of Appendix "A" to 10 CFR 50. q The ACTION requirements specified'for the levels of degradation of the power sources provide restriction upon continued facility operation commensurate l with the level of degradation. The OPERABILITY of' the power sources are J consistent with the initial conditicn assumptions of the safety analyses and' L are based upon maintaining at least one redundant set of onsite A.C. and D.C.  :

power sources and associated distribution systems OPERABLE during accident  ;

conditions coincident with an assumed loss of-offsite power and single failure -

of the other onsite A.C. source. The A.C. and D.C. source allowable out-of-service times are based on Regulatory Guide 1.93, " Availability of Electrical Power Sources," December 1974. When one diesel generator is inoperable, th re is an additional ACTION requirement to verif i

i subsystems, trains, components and devices, y that that all required depehd systems, on the remaining OPERABLE diesei generator as a source of emergency power, are also OPERABLE, and that the steam-driven auxiliary feedwater pump is OPERABLE. This require-ment is intended to provide assurance that a loss of offsite power event will L

.not result in a complete loss of safety function of critical systems during the period one of the diesel generators is inoperable. The term verify as used in this context means to administratively check by examining logs or other information to determine if certain components are out-of-service for maintenance or other reasons. It does not mean to perform the surveillance requirements needed to demonstrate the OPERABILITY of the component.

The OPERABILITY of the minimum specified A.C. and D.C. power sources and associated distribution systems during shutdown and refueling ensures that  !

1) the facility can be maintained in the shutdown or refueling condition for extended time' periods and 2) sufficient. instrumentation and control capability

-is available for monitoring and maintaining the unit status.

The Surveillance Requirements for demonstrating the OPERABILITY of the  !

l diesel generators are in accordance with the recommendations of Regulatory Guides 1.9, " Selection of Diesel Generator Set Capacity for Standby Power Supplies," Harch 30,1971,1.108, " Periodic Testing of Diesel Generator Units L'

H Used as Onsite Electric Power Systems at Nuclear Power Plants," Revision 1,  ;

August 1977, and 1.137, " Fuel-Oil Systems for Standby Diesel Generators," '

Revision 1, October 1979, as modified by the NRC's review and . approval of South  !

Carolina Electric & Gas Company's June 10, 1985 and December 6,1985 amendment i requests.

TA/MRT /  ?

c SUMMER - UNIT 1 B 3/4 8-1 AMENDMENT 77

ATTACHMENT 1-I TECHNICAL SPECIFICATION PAGES WITH THE REQUESTED CHANGES ,

INDICATED l- Paae Specification Chance Description

.e s 3/48-1 3.8.1.1 Changes item b.2 limit from 42,500 gallons to 47,100 gallons 3/48-8 3.8.1.2 Changes item b.2 limit from 30,000 gallons to 33,200 gallons B 3/4 8-1 Bases for Adds specific references to the origin 3/4.8.1, 3/4.8.2 of the volume requirements and 3/4.8.3

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Insert I to Attachment i

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t The fue's storage system minimum volume of fuel to demonstrate operability of the diesel generators was based on fuel consumotion determined from time dependent loads following a design basis accident and a loss of1 off site power as listed in FSAR Table 8.3-3 for seven days plus a 10% fuel margin as recommended in Regulatory Guide 1.137 Revision 2, " Fuel-011 Systems for Standby Diesel Generators " position C.1.C(2).

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'E ATTACHMENT 2 DESCRIPTION OF AMENDMENT REQUEST I

SAFETY EVALUATION v

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_D Attachment 2'to Document Control Desk Letter December 11, 1989 3 Pags 1 of 1-DESCRIPTION OF AMENDMENT REQUEST:

Technical Specifications 3/4.8.1 and 3/4.8.1.2 "A. C. Sources" ensures that sufficient power is available to supply safety related equipment that is required for the safe shutdown of the plant or mitigation and control of accident conditions. One way this is accomplished is by maintaining the fuel oil storage volume requirements of these specifications which is 42,500 gallons for specification 3/4.8.1.1 (Modes 1-4) and 30,000 gallons for specification 3/4.8.1.2 (Modes 5 & 6).

i On April 28,1989 SCE&G recognized that the current design basis calculations l

.per ANSI' standard N195-1976 yeilded Fuel Oil Storage requirements of 47,100 gallons in Modes 1 thru 4 and 33,200 gallons in Modes 5 and 6. Therefore, it is requested that the Fuel Oil Storage System requirements be changes from 42,500 gallons to 47,100 gallons for Specification 3/4.8.1.1 and from 30,000 gallons to 33,200 gallons for Specification 3/4.8.1.2, and that a change to the specification bases 3/4.8 " Electrical Power Systems" be made to clarify the origin of the fuel Oil System volume requirements.

SAFETY EVALUATION:

The following is an evaluation to determine if safety is compromised by sincreasing the required volume _in the Fuel Oil Storage System with regards to the ability of Diesel Generator to meet General Design Criteria 17 of 10CFR50 Appendix "A".

ANSI standard NI95-1976 " Fuel Oil Systems for Stand-By Diesel Generators" provides the method of calculation for Fuel Oil Storage Volume Requirements.

This standard is accepted by the NRC as meeting General Design Criterion 17 of 100FR50, Appendix "A", and is referenced by Regulatory Guide 1.137. .

The current calculation results, based on the ANSI standard, indicated increased volume storage requirements were necessary; 47,100 gallens for specification 3.8.1.1 and 33,200 gallons for specification 3.8.1.2.

Therefore, increasing the minimum volume requirement brings the limit inside the standards of General Design Criterion 17 of 10CFR50 Appendix "A", and results in a greater benefit to safety.

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,; . I ATTACHMENT 3 k

- DESCRIPTION OF AMENDMENT REQUEST NO SIGNIFICANT HAZARDS DETERMINATION t

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[- & -Attachment 3 to Document Control Desk Letter 1,~.  ; December 11, 1989 e Page 1 of l' DESCRIPTION OF AMENDMENT REQUEST:

p Technical Specifications 3/4.8.1 and 3/4.8.1.2 "A. C. Sources" ensures that sufficient power is available-to supply safety related equipment that is required for the safe shutdown of the plant or mitigation and control of accident conditions. One way this is accomplished is by maintaining the fuel oil storage volume requirements of these specifications which is 42,500.

gallons for specification 3/4.8.1.1 (Modes 1-4) and 30,000 gallons for specification 3/4.8.1.2 (Modes 5 & 6).

On April 28,1989 SCE&G recognized that the current design basis calculations per ANSI standard N195-1976 yeilded Fuel Oil Storage requirements of 47,100

gallons in Modes 1 thru 4 and 33,200 gallons in Modes 5 and 6. Therefore, it  !

is requested that the fuel Oil Storage System requirements be changes from l 42,500 gallons to 47,100 gallons for Specification 3/4.8.1.1 and from 30,000

-gallons to 33,200 gallons for Specification 3/4.8.1.2, and that a change to the specification bases 3/4.8 " Electrical Power Systems" be made to clarify the origin of the fuel Oil System volume requirements.

SIGNIFICANT HAZARDS DETERMINATION:

Upon review of the proposed amendment, it has been determined that no significant hazard considerations exist as explained by the following:

1. This change does not involve a significant increase in the ,

probability or consequences of any accident previously accidents.  !

This is due to the change imposing.more restrictive limits than j currently exist thus relaxing, the potential for, and, the results y of, any of the previously evaluated accidents involving the l operability of the Diesel Generators.

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2. This change does not create the possibility of a new or different of l accident from any accident previously evaluated because the increase-in the Fuel Oil Storage requirement ensures a higher level of reliability for the Diesel Generators. j

3. This change does not involve a significant reduction in a margin of l safety since the increase in fuel oil storage requirements represents a more restrictive limit than currently exist and, therefore, represents and enhancement to safety. j i

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