ML15113A083

Amends 127,127 & 124 to Licenses DPR-38,DPR-47 & DPR-55, Respectively,Revising Tech Specs to Implement Limiting Conditions for Operation in Event One Startup Transformer Out of Svc

ML15113A083
Person / Time
Site:	Oconee
Issue date:	03/02/1984
From:	Stolz J Office of Nuclear Reactor Regulation
To:	Duke Power Co
Shared Package
ML15113A084	List: ML15113A083 ML15113A085
References
DPR-38-A-127, DPR-47-A-127, DPR-55-A-124 NUDOCS 8403150335
Download: ML15113A083 (21)

Text

~pR REG(J UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 DUKE POWER COMPANY DOCKET NO. 50-269 OCONEE NUCLEAR STATION, UNIT NO. 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 127 License No. DPR-38

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

A. The application for amendment by Duke Power Company (the licensee) dated March 17, 1983, 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 (ii) 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.

2. Accordingly, the license is amended by changes to the Technical Specifications as.indicated in the attachment to this license amendment, and paragraph 3.B of Facility Operating License No. DPR-38 is hereby amended to read as follows:

3.8 Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 127are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

8403150335 840302 PDR ADOCK.05000269 P

PDR

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3. This license amendment is effective as of the date of its issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Joh F. Stolz, Chie Op rating Reactors Branch No. 4 vision of Licensing

Attachment:

Changes to the Technical Specifications Date of Issuance:

March 2, 1984

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 DUKE POWER COMPANY DOCKET NO. 50-270 OCONEE NUCLEAR STATION, UNIT NO. 2 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 127 License No. DPR-47

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

A. The application for amendment by Duke Power Company (the licensee) dated March 17, 1983, 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 (ii) 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.

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Facility Operating License No. DPR-47 is hereby amended to read as follows:

3.B Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 127are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

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3. This license amendment is effective as of the date of its issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Joh F. Stolz, Chief&

O rating Reactors Branch No. 4 ivision of Licensing

Attachment:

Changes to the Technical Specifications Date of Issuance:

March 2, 1984

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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 DUKE POWER COMPANY DOCKET NO. 50-287 OCONEE NUCLEAR STATION, UNIT NO. 3 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No.124 License No. DPR-55

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

A. The application for amendment by Duke Power Company (the licensee) dated March 17, 1983, 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 (ii) 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.

2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Facility Operating License No. DPR-55 is hereby amended to read as follows:

3.B Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No.124 are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

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3. This license amendment is effective as of the date of its issuance.

FOR THE NUCLEAR REG LATORY COMMISSION oh F. Stolz, Chief Op ating Reactors Branch No. 4 vision of Licensing

Attachment:

Changes to the Technical Specifications Date of Issuance:

March 2, 1984

ATTACHMENTS TO LICENSE AMENDMENTS AMENDMENT NO. 127 TO DPR-38 AMENDMENT NO. 127 TO DPR-47 AMENDMENT NO. 124 TO DPR-55 DOCKETS NOS. 50-269, 50-270 AND 50-287 Replace the following pages of the Appendix "A" Technical Specifications with the attached pages.

The revised pages are identified by amendment numbers and contain vertical lines indicating the area of change.

Remove Pages Insert Pages vi vi 3.7-1 3.7-1 3.7-2 3.7-2 3.7-4 3.7-4 3.7-5 3.7-5 3.7-6 3.7-6 3.7-7 3.7-7 3.7-8 3.7-8 3.7-9 3.7-9 3.7-10 3.7-10 3.7-11 3.7-11 3.7-12 3.7-12 3.7-13 3.7-13 3.7-14 3.7-14

LIST OF TABLES Table No.

Page 2.3-LA Reactor Protective System Trip Setting Limits - Unit 1 2.3-11 2.3-1B Reactor Protective System Trip Setting Limits -

Unit 2 2.3-12 2.3-10 Reactor Protective System Trip Setting Limits -

Unit 3 2.3-13 3.5-1-1 Instruments Operating Conditions 3.5-4 3.5-1 Quadrant Power Tilt Limits 3.5-14 3.5.5-1 Liquid Effluent Monitoring Instrumentation Operating 3.5-36 Conditions 3.5.5-2 Gaseous Process and Effluent Monitoring Instrumentation 3.5-38 Operating Conditions 3.7-1 Operability Requirements for the Emergency Power 3.7-14 Switching Logic Circuits 3.17-1 Fire Protection & Detection Systems 3.17-3 4.1-1 Instrument Surveillance Requirements 4.1-3 4.1-2 Minimum Equipment Test Frequency 4.1-9 4.1-3 Minimum Sampling Frequency and Analysis Program 4.1-10 4.1-4 Radioactive Effluent Monitoring Instrumentation 4.1-16 Surveillance Requirements 4.2-1 Oconee Nuclear Station Capsule Assembly Withdrawal 4.2-3 Schedule at Crystal River Unit No. 3 4.4-1 List of Penetrations with 10 CFR 50 Appendix J Test 4./-6 Requirements 4.11-1 Radiological Environmental Monitoring Program 4.11-3 4.11-2 Maximum Values for the Lower Limits of Detection (LLD)

.11-5 4.11-3 Reporting Levels for Radioactivity Concentrations in 4.11-8 Environmental Samples 4.17-1 Steam Generator Tube Inspection 4.17-6 6.1-1 Minimum Operating Shift Requirements with Fuel in Three 6.1-6 Reactor Vessels Vi Amendments Nos. 127, 127, 124

3.7 AUXILIARY ELECTRICAL SYSTEMS Applicability Applies to the availability of off-site and on-site electrical power for station operation and for operation of station auxiliaries.

Objective To define those conditions of electrical power availability necessary to provide for safe reactor operation and to provide for continuing availability of engineered safety features systems in an unrestricted manner and to pre scribe safety evaluation and reporting requirements to be followed in the event that the auxiliary electric power systems become degraded.

Specifications 3.7.1 Except as permitted by 3.7.2, 3.7.3, 3.7.4, 3.7.5, 3.7.6, 3.7.7, and 3.7.8, the reactor shall not be above 200 0F unless the following con ditions are met.

(a) At least two 230KV transmission lines, on separate towers, shall be in service.

(b) Two independent on-site emergency power paths shall be operable and shall consist of:

1.. One Keowee hydro unit; through the underground feeder path; through transformer CT4; and to one 4160V standby bus.

2. The second Keowee hydro unit; through the Keowee main step-up transformer; through the overhead path and breaker PCB9; the 230KV switchyard yellow bus and safety related PCB-18, -27, or -30; through the respective operating unit's startup trans former (CT-1, 2, or 3) of the aligned and connected alternate startup transformer. One startup transformer may not be aligned to supply power to more than one unit.

(c) The Emergency Power Switching Logic (EPSL) circuitry shall be operable as specified by the conditions of Table 3.7-1 for normal operation. Furthermore, if the reactor is subcritical, the conditions of Table 3.7-1 for normal overation shall be satisfied before the reactor is returned to criticalicy.

(d) Two 4160 volt main feeder buses shall be energized.

(e) The three 4160 volt Engineered Safety Features switchgear buses (TC, TD, and TE), three 600 volt load centers (X8, 9, and 10),

and the three 600-208 volt Engineered Safety Features MCC Buses shall be energized.

(f) For each unit, the 125 VDC Instrumentation and Control Power System shall be operable as specified below:

3.7-1 Amnd..ncmnts -s. 117, 127, 124

1.- Both 125 VDC instrumentation and control distribution centers (DCA and DCB);

2.

All four 125 VDC instrumentation and control panelboards (DIA, DIB, DIC, and DID),

including the associated isolating transfer diodes and diode monitors (ADA I & 2, ADB I & 2.

ADC 1 & 2, ADD 1 & 2);

3.

All four 120 VAC vital instrumentation power panelboards (KVIA, KVIB, KVIC, and KVID), including the associated static inverters;

4.

The 240/120 VAC regulated power panelboard (KRA).

Additionally, the 125 VDC instrumentation and control batteries with an associated charger shall be operable as follows:

1. For operation of Unit 1 only, ICA or ICB, and 2CA and 2CB Unit 2 only, 2CA or 2CR, and 3CA and 3CB Unit 3 only, 3CA or 3CB, and ICA and ICB

2. For op.eration of any two units, ICA or ICB, 2CA or 2CR, and 3CA or 3CB.

3. For operation of all three units, five of the six batteries with their associated chargers.

(g) Both of the 125 VDC 230KV switching station batteries (SY-1, SY-2),

with associated chargers,. distribution centers, and panel boards shall be operable.

(h) Both of the 125 VDC Keowee batteries (Bank 1 & 2) with as sociated chargers and distribution centers (IDA & 2DA) shall be operable.

(i) The level of Keowee Reservoir shall be at least 775 feet above sea level.

3.7.2 With the reactor above 200aF, provisions of 3.7.1 may be modified to allow the following conditions to exist:

(a) One of the two independent on-site emergency power paths, as defined in 3.7.1(b), may be inoperable for periods not exceeding 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for test or maintenance, provided the alternate cower path is verified overable within one hour of the Loss and every eight hours thereafter.

(b) The circuits or channels of any single functional unit of the EPSL may be inoperable for test or maintenance for periods not exceeding 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, provided that:

1. The conditions of Table 3.7-1 for degraded operation are satisfied for that specific functional unit; and

2. The conditions of Table 3.7-1 for normal operation are satisfied for all other functional units.

3.7-2

.2 d!c,'t 2S.2,17 2

an equalizer charge after the surveillance requirements of Specifica tion 4.6.10.

1. 230 KV Switching Station 125VDC Power System

2. Keowee Hydro Station 125VDC Power System

3. Each unit-'s 125VDC Instrumentation and Control Power System, provided that the unit's remaining battery is operable.

However, for operation of 1 or 2 units, no more batteries than those allowed to be inoperable per 3.7.1 (f) may be removed from service. For operation of 3 units, at least 4 of the 6 station I&C batteries shall be"operable.

(h) One 120 VAC vital instrumentation power panelboard per unit and/or

-its associated static inverter may be inoperable for periods as snecified below:

Maximum Allowed Period Panelboard of Inoperabilitv KVIA 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> KVIB 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> KVIC 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> KVID 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> A single vital bus static inverter per unit may continue to be inoperable beyond the specified period, but no longer than 7 days total, provided that its associated 120 VAC vital.instrumentation power panelboard is connected to the 240/120.VAC Regulated Power System and verified to be operable once every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

(i) 1. A startup transformer may be inoperable for periods not ex ceeding 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for test or maintenance, provided the under ground feeder pat4, through transformer CT4; and to one 4160V standby bus is verified operable within one hour of loss and every eight hours thereafter. The remaining oper able startup transformers can be shared between units withi in the same 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of the above startup transformer being determined inoperable. Prior to exceeding 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, :hev shall be aligned and connected such that each one is pro viding a path for power to one and only one unit.

2. In the event that a startup transformer becomes inoperable for unplanned reasons, then one unit shall be in cold-shut down within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with its loads powered from the stand by buses. The remaining operable startup transformers can be shared between units within the same 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of the above startup transformer being determined inoperable. Prior to exceeding 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, they shall be aligned and connected such that each one is.

providing a path for power to one and only one unit.

3.7-4 mr drMnen

• i 27 1,,S7,SI 124

3.7.3 In the event that the conditions of Specifications 3.7.1 are not met within the time specified in Specification 3.7.2, except as noted below in Specification 3.7.4, 3.7.5, 3.7.0, 3.7.7, and 3.7.3, the reactor shall be placed in a hot shutdown condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

if these requirements are not met within an additional 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, the reactor shall be olaced in the cold shutdown condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3.7.4 In the event that all conditions in Specification 3.7.1 are met ex cept that one of the two Keowee hydro units is expected to be un available for longer than the test or maintenance period of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the reactor may be heated above 200 0F if previously shutdown or be permitted to remain critical or be restarted provided the following restrictions are observed.

(a) Prior to heating the reactor above 200'F or prior to the re start of a shutdown reactor or within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of the loss of one Keowee hydro unit, the 4160 volt standby buses shall be energized by a Lee gas turbine through the 100 kV circuit.

The Lee gas turbine and 100 kV transmission circuit shall be electrically separate from the system grid and offsite non safety-related loads.

(b) The remaining Keowee hydro unit shall be connnected to the under ground feeder circuit and this path shall be verified operable within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and weekly thereafter.

(c) The remaining Keowee hydro unit shall be available to the overnead transmission circuit but generation of the system grid shall be prohibited except for periods of test.

(d) Operation in this mode is restricted to periods not to exceed 45 days and the provisions of this specification may be utilized without prior NRC approval only once in three years for each Keowee hydro unit.

The U.S. NRC Regional Office, Region II, will be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3.7.5 In the event that all conditions of Specification 3.7.1 are met ex cept that all 230 kV transmission lines are lost, the reactor shall be permitted to remain critical or be restarted provided the following restrictions are observed:

(a) Prior to the restart of a shutdown reactor or within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of losing all 230 kV transmission lines for an.operating reac tor, the 4160 volt standby buses shall be energized. by one of the Lee gas turbines through the 100 kV transmission circuit.

The Lee gas turbine and the 100kV transmission circuit shall be completely separate from the system grid and offsite non-safety-.

related loads.

(b) The reactor coolant T shall be above 325 0F. Reactor cooLant avg pump power may be used to elevate the temperature from 500OF to 5250 in the case of restart.

If I

aecreases below 5000F, restart is not permitted by this speciication.

3.-

'~

Amendments Nos.

127, 127, 124

(c) If all 230 kV transmission lines are lost, restore at least one of the inoperable 230 kV offsite sources to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in at least hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

With only one offsite source restored, restore at least two 230 kV offsite circuits to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from time of initial loss 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 in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

(d) After loss of all 230 kV transmission lines, this information shall be reported within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to the U.S.

NRC Regional Office, Region II.

If the outage is expected to exceed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, a written report snail oe submitted detailing :he cir cumstances of the outage and the estimated time to return the 230 kV transmission lines to operating condition.

3.7.6 In the event that all conditions of Specification 3.7.1 are met, and planned tests or maintenance are required which will make both Keowee units unavailable, the 4160 volt standby buses shall first be ener gized by a Lee gas turbine through the 100 kV transmission circuit and shall be separate from the system grid and offsite non-safety-related loads.

The reactor shall then be permitted to remain critical for periods not to exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with both Keowee units unavailable.

Prior to hot restart of a reactor from a tripped condition, the causes and the effects of the shutdown shall be established and analyzed.

A restart will be permitted if the cause of. such trips is the result of error or of minor equipment malfunctions. A restart will not be permitted if the trip is a result of system transients or valid pro tection system action.

3.7.7 In the event that all conditions of Specification 3.7.1 are met except that both Keowee hydro units become unavailable for unplanned reasons, the reactor shall be permitted to remain critical for periods not to exceed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> provided the 4160 volt standby buses are energized within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> by the Lee gas turbine through the 100 kV transmission circuit and it shall be separate from the system grid and all offsite non safety-related loads.

Prior to hot restart of a reactor from a tripped condition, the causes and the effects of the shutdown shall be established and analyzed. A restart will be permitted if the cause of such trips is the result of error or of minor equipment malfunctions. A restart will not be per mitted if the trip is a result of system transients or valid protec tion system action.

3.7.8 In the event that all conditions in Soecification 3.7.1 are met excevt that the Keowee Main Step-up Transformer is expected to be unavailable for longer than the test or maintenance period of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, as allowed by 3.7.2(a), the reactor may be heated above 200 degrees F if previously shutdown or be permitted to remain critical or be restarted provided the following restrictions are observed:

3d-n a..0Amendments Nos. 127, 127, 124

(a) Prior to heating the reactor above 200 degrees F or prior to the restart of a shutdown reactor or within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of the loss of the Keowee Main Step-up Transformer, the 4160 volt standby buses shall be energized by a Lee gas turbine through the 100kV circuit.

The Lee gas turbine and 100kV transmission circuit shall be elec trically separate from the system grid and off-site and non-safety related loads.

(b) A Keowee hydro unit shall be connected to the underground feeder circuit and this path shall be verified operable within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and weekly thereafter.

(c) The remaining Keowee Hydro Unit shall be available to the under ground feeder circuit.

(d) Operating in this mode is restricted to periods not to exceed 23 days and the provisions of this specification may be utilized without prior NRC approval.

The U.S. NRC Regional Office, Region II, will be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3.7.9 Any degradation beyond Specifications 3.7.2, 3.7.'4, 3.7.5, 3.7.6, 3.7.7, and 3.7.3 above shall be reported to the U.S.

NRC Regional Office,,Region II, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. A safety evaluation shall be performed by Duke Power Company for the specific situation involved which justifies the safest course of action to be taken. The results of this evaluation together with plans for expediting the return to the unrestricted operating conditions of Specification 3.7.1 -above shall be submitted in a written report to the Office of Nuclear Reactor Regulation with a copy to the U.S.

NRC Regional Office, Region II, within five days.

Bases The auxiliary electrical power systems are designed to supply the required Engineered Safeguards loads in one unit and safe shutdown loads of the other two units and are so arranged that no single contingency can inactivate enough engineered safety features to jeopardize plant safety. These systems were designed to meet the following criteria:

"Alternate power systems shall be provided and designed with adequate independency, redundancy, capacity and testability to permit the functions required of the engineered safety features of each unit."

The auxiliary power system meets the above criteria and the intent 3f Criterion 17 of Appendix A to 10 CFR Part 50.

The adequacies of the AC and DC systems are discussed below as are the bases for permitting degraded conditions for AC power.

Canacitv of AC Systems The auxiliaries of two units in hot shutdown (6.0MVa each) plus the auxiliaries activated by ESG signal in the other unit (4.3 MVa) require a total AC power capacity of 16.8 MVa.

The continuous AC power capacity available from the on site power systems (Keowee Hydro Units) is 20 Va (limited by transformer CT) 3.7-7 Amendments Nos. 127, 127, 1241

if furnished by the underground circuit or 30 -Va (limited by CTI or CT2) if furnished through the 230 kV off-site transmission lines.

CaDacity available from the backup 100 kV off-site transmission line (Lee Station Gas Turbine Generator) is 20 MVa (limited by CT5).

Thus, the minimum available capacity from any one of the multiple sources of AC power, 20 fVa, is adequate.

The adequacy of the Oconee electrical distribution system voltages has been evaluated. Under the conservative assumptions of the analysis, it has been established that a: single startup transformer should not be shared between two operating units. In the event a startup transformer becomes inoverable, it effectively causes one onsite emergency power path to the affected.unit to become inoperable. The time frames for the degraded mode of an inoperable startup transformer are thus consistent with those for an inoperable onsite emergency power path. Because the preferred mode of unit shutdown is with reactor coolant pumps providing forced circulation and because of the low likelihood of an accident during a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> -period, the unit which is being shut down is allowed to share a startup transformer with another unit until the unit is in cold shutdown with loads-being powered from.the standby buses.

Caoacity of DC Systems Normally, for each unit AC power is rectified and supplies the DC system buses as well as keeping the storage batteries on these buses in a charged state.

Upon loss of this normal AC source of power, each unit's DC auxiliary systems important to reactor safety have adequate stored capacity (ampere-hours) to indenendentiv supply their required emergency loads for at least one hour. One hour is consider2-d to be conservative since there are redundant sources of AC power providing energy to these DC auxiliary systems. The loss of all AC power to any DC system is ex pected to occur very infrequently, and for very short periods of time. :he follCwi:;

taoulation demonstrates the margin of installed battery charger rating and baztery capacity when compared to one hour of operation (a) with AC power (in amps) and (b) without AC power (in ampere hours) for each of the three safety-related DC.. systems installed at Oconee:

A.

125 VDC Instrumentation and Control Power System Charger XCA, XCB, or XCS

a.

600 amps each Battery XCA or XCB Capacity

b.

600 amere-dours each (X = 1, 2, or 3)

Combined total connected loads

a.

inrush (2 sec',-

1160 amns on both 125 VDC I & C buses DCA and DCB aext 59 min.

506 amps during 1st hour of LOCA

b.

316.9 ampere-hours' (x

1,2, or 3)

B.

125 VDC Switching Station Power System Charger SY-1, SY-2, or SY-s Rating

a.

50 amps each Battery SY-1 or SY-2 Capacity

b.

14.4 amoere-hours Active load per battery

a.

nrush (2 seconds) -60 am during 1st hour of LOCA next 59 min. -

'10 amus 3.7-8 Amendments Nos. 127,

127, 124

b.

12 ampere-hours C.

125 VDC Keowee Station Power System Charger No. 1, No. 2 or Standby Rating

a.

200 amps each Battery No. 1 or No. 2 Capacity

b.

200 ampere-hours Active load per battery

a.

Inrush (14 seconds) -

1031 amps during 1st hour of LOCA next 59 min.. -

179.4 amps

b.

193.6 ampere-hours Redundancy of AC Systems There are three 4160 V engineered safety feature switchgear buses per unit. Each bus can receive power from either of the two 4160 V main feeder buses per unit.

Each feeder bus in turn can receive power from the 230 kV switchyard through the startup transformers, through the unit auxiliary transformer by backfeeding through the main step-up transformer, or from the 4160V standby bus.

Another unit's start up transformer serving as an alternate supply can be placed in service in one hour.

The standby. bus can receive power from the hydro station through 'the underground feeder circuit or from a combustion turbine generator at the Lee Steam Station over an isolated 100 kV transmission line. The 230 kV switchyard can receive power from the on-site Keowee hydro station or from several off-site sources via transmission lines which connect the Oconee Station with the Duke Power system power distribution network.

Redundancy of DC System A.

125 VDC Instrumentation and Control Power System The 125 VDC Instrumentation and Control (I&C) Power System consists of two batteries, three battery chargers, and two I&C distribution centers per unit. All reactor protection and engineered safety features loads on this system can be powered from either the Unit 1 and Unit 2 or Unit 2 and Unit 3 or Unit 3 and Unit 1 125 VDC I&C distribution centers.

The 125 VDC I&C distribution centers are normally supplied from their associated battery and charger. For one unit, in the event that only one of its bat teries and associated chargers are operable, both I&C distribution centers will be tied together allowing operation of the DC Loads from the unit's operable battery and charger. As shown above, one I&C battery (e.g., ICA) can supply both I&C distribution centers (e.g., IDCA and IDCB) and their associated panelboard loads.

Also, one of the three battery chargers for each unit can supply all connected ESF.and reactor protection Loads.

In order to find and correct a DC ground on the 125 VDC instrumentation and Control system each unit's DC system must be separated from the other two units. This is due to the interconnected design of the system. 'With the backup function disabled the units would be in a degraded mode but would in fact have all of its own DC system available if needed.

Each unit's batteries either CA or CB is capable of carrying all the 125 VDC Instrumentation and Control loads on that unit.

3.7-9 Amendments Nos.

127, 127, 124

B.

125 VDC Switching Station Power System There are two essentially independent subsystems each complete with an AC/DC power supply (battery charger), a battery bank, a battery charger bus, motor control center (distribution panel).

Except for the support racks for the batteries, all safety-related equipment and the relay house in which it is located are seismic Category I design. The support racks for the batteries will be upgraded to seismic Category I as soon as possible. Each sub-system provides the necessary DC power to:

a.

Continuously monitor operations of the orotective relaying

b.

Isolate Oconee (including Keowee) from all external 230 kV grid faults,

c.

Connect on-site power to Oconee from a Keowee hvdro unit or,

d.

Restore off-site power to Oconee from non-faulted portions of the external 230 kV grid.

Provisions are included to manually connect a standby battery charger to either battery/charger bus.

C.

125 VDC Keowee Station Power System There -are essentially two independent physically separated seismic Category7 7 subsystems, each complete with an AC/DC power supply (charger), a batter-7 bank, a battery/charger bus and a DC distribution center.

Each subsy-stem provides the necessary power to automatically or manually start, control and protect one of the hydro units.

An open or short in any one battery charger, or DC distribution center, cannot cause loss of both hydro uni:s.

The 230 KV sources, while expected to have excellent availabilicy, are not under the direct control of the Oconee station and, based on past experience, cannot be assumed to be available at all times.

However, the operation of the onsite hydro-station is under the-direct control of the Oconee Station and requires no offsite power to startup. Therefore, an onsite backun source of auxiliary power is provided in the form of twin hydro-electric turbine generators powered through a common penstock by water taken from Lake Keowee. The use of a common penstock is justified on the basis of past hydro plant experience of the Duke Power Company (since 1919) which indicates that the cumulative need to dewater the penstock can be expected to be limited to about one day a year, principally for inspection. plus perhaps four days every tenth year.

Operation with one Keowee Hydro unit out of service for periods less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is permitted.

The operability of the remaining Keowee hvdro unit is verified within one hour by starting the unit and energizing the standby buses through the underground feeder circuit. This action is reveated once every eight hours thereafter until the Keowee hydro unit is restored to service and will provide additional assurance of the ooerability of the remaining unit.

3.7-10 Amendments Nos. 127, 127, 124

Provisions have been established for those conditions in which long term pre ventative maintenance of a Keowee Hydro unit are aecessary. The primary long term maintenance items are expected to be hydro turbine runner and discharge ring welding repairs which are estimated to be necessary every six to eight years.

Also, generator thrust and guide bearing replacements will be necessary.

Other items which manifest as failures are expected to be extremely rare and could possibly be performed during the permitted maintenance periods.

Time periods of up to 45 days for each Keowee Hydro unit are permitted every three years.

During these outages the remaining Keowee Hydro unit will be verified to be operable within one hour and weekly thereafter by starting the unit and energizing the underground feeder circuit. The remaining Keowee hydro unit will also be available through the overhead transmission path and will not be used for system peaking. Additionally, the standby buses will be energized continuously by one of the Lee gas turbines through the 100 kV transmission circuits.

This transmission circuit would be electrically separated from the system grid and all off-site non-safety-related loads.

This arrangement provides a high degree of reliability for the emergency power systems.

Operation with both Keowee Hydro units out of service is permitted for planned or unplanned outages for periods of 72 or 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> respectively. Planned outages are necessary for the inspection of common underwater areas such as the penstock and to enable the removal of one Keowee unit from service. This would be a controlled evolution in which the availability and condition of the offsite grid, startup transformers and weather would be evaluated and a Lee gas turbine would be placed in operation on the isolated 100 kV transmission Line prior to commencement of the outage.

A time period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for unplanned outages of both Keowee units is accept able since a Lee gas turbine will be started within one hour and will energize the standby buses through the dedicated 100 kV transmission line.

This period of time is reasonable to determine and rectify the situation which caused the:

loss of both Keowee units.

If the overhead power path from Keowee is inoperable for more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> due to an extended outage of the Keowee main step-up transformer, operation is per mitted provided that certain actions are taken to ensure the quick availability of emergency power. These actions include:

continuous energization of the standby buses by a Lee gas turbine through the 100kV transmission circuits; connection of a Keowee.unit to the underground feeder path and periodic veri fication of its operability; and, availability of the remaining Keowee unit to the underground feeder path. Operation in this mode is permitted for a maximum of 28 days, which allows a reasonable period of time to remove the existing trans former and install a replacement.

In the event that none of the sources of off-site power are available and it is considered important to continue to maintain an Oconee reactor critical or return it to criticality from a hot shutdown condition, one of the Lee gas turbines can be made available as an additional backup source of power, thus assuring continued availability as an auxiliary power to perform an orderly shutdown of a unit should a problem develop requiring shutdown of both hydro units.

.7-11 mendments 'os.

127, 127, 124

7mereencv Power Switching Logic Circuits The Emergency Power Switching Logic (EPSL) in conjunction with its assoc:ates circuits, is designed with sufficient redundancy to assure that oower is suotied to the unit Main Feeder Buses and, hence, to the unit's essential loads, under accident conditions.

The logic system monitors the normal and emergency power sources and, upon loss of the normal power source (the unit auxiliary transformer),

the logic willseek an-alternate source or Dower.

Operation of the unit with certain circuits or channels of the EPSL inoverable for test or maintenance is permitted for periods of up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, provided that the inoperable circuits/channels are in only one portion, or functional unit,. of the EPSL' and provided that a sufficient number of circuits/channels in the affected functional unit remain operable such that the functional unit does not lose its ability to perform its designed safety function. These provisions ensure that only one portion of the EPSL is degraded at a time for test or maintenance and that the affected portion remains operable although degraded.

If the circuits or channels of more than one functional unit are inooerable, con

inued operation is permitted provided that the inoperabilizy results from a loss of power due to the inoperability of a 125 VDC instrumentation and control oanel board. In addition, the affected functional units must remain canable of Der forming their designed safety functions in spite of the inoperaole circuits/channels.

By itself, the inoperability of a 125 VDC instrumentation and control panelboard will not.cause the complete loss of any EPSL functional unit.

It will, however, degrade some of the functional units because of the resulting loss or oower to some of the circuits/channels.

If other circuits/channels of the ESL functional units are already inoperable, then a 125 VDC instrumentation and control canel board becoming inoperable could cause a loss oi function in portions of :e EPSL.

For that reason, operation is permitted with an inoperaile oanelboard oniv if the EPSL was not in a degraded mode prior to the panelboard becoming inoperable.

In the event that the EPSL is in a degraded mode while the reactor is subcritical.

a return to criticality may not be made until the EPSL is returned to a normal operational status.

This ensures the availability of the EPSL during all reactor startups.

120 VAC Vital Instrument Power Panelboards For each unit, four redundant 120 VAC vital instrument Dower oanelboards are provided to supply power in a predetermined arrangement to vital power, instru mentation, and control loads under all operating conditions.

Each paneiboard is supplied power separately from a static inverter connected to one or one four 125 VDC instrumentation and control power panelboards.

In addition, a :ie with breakers is provided to each of the 120 VAC vital Danelboards from the alcernate 120 VAC regulated bus to provide backup for each vital panelboard and to permit servicing of the inverters.

For each unit, each of the four redundant channels of the nuclear instrumentation and reactor protective system (RPS) equipment is supplied power from 3 separate 120 VAC vital panelboard.

Also for each unit, each of the three redundant engin eered safety features actuation system (ESFAS) analog channels and each of the two redundant ESFAS digital channels are powered from separate vital panelboards.

3.7-12 Amendments Nos. 127, 127, 124

The period allowed for corrective action on an inoperable vital panelboard depends on the loads carried by the affected panelboard. For example, panelboards KVIA and KVIB are allowed to be inoverable for only four hours because tHey provide power to the digital ESFAS channels, which are in turn allowed to be inoperable for only four hours by Technical Specification 3.5.1.

In contrast, panelboards KVIC and KVID carry loads which do not necessarily become inoperabie upon Loss of power (e.g., RPS channels and ESFAS analog channels go to a tripped state upon loss of power) and thus do not necessitate immediate corrective action. Thus, these panelboards have been limited to a period of inoperability which does not exceed that allowed for their normal source of power, the 125 VDC instrumentation and control panelboards.

In the event that 'failure of a static inverter results in the inoperability of its associated vital panelboard, the affected panelboard may be tied to the 240/

120 VACregulated power system and unit operation may continue for seven days.

This specification allows sufficient time for the inverter to be repaired without penalizing unit operation by permitting the use of.alternate power sources.

3.7-13 Amendments Nos. 127, 127, 124

TABLE 3.7-1 OPERABILITY REQUIREIMENTS FOR THE EIERGENCY POWER SWITCHING LOGIC CIRCUITS Minimum Operable Circuits/Channels Functional Unit Normal Operation Degraded Operation Per Spec 3.7.1(c).

Per Spec 3.7.2(b) 1.. Normal Source Voltage 3

Sensing Circuits (One per Phase)

2. Startup Source Voltage 3

2 Sensing Circuits (One per Phase)

3. Standby Bus Voltage 6

4a Sensing Circuits (One per Phase on each bus)

4. Main Feeder Bus Undervoltage 6

4a Relays (Three per bus)

5. Load Shed and Transfer to Standby 2

1 Circuits (Channels A and B)

6. Keowee Emergency Start Circuit 2

1 (Channels A and B)

7. Normal Source Breakers N1 b

2c and N2 Control Circuitry

8. Startup Source Breakers El and E2 Control Circuitry 4

9. Standby Bus to Main Feeder Bus 4b Breakers, SI and S2, Control Circuitry (Including Retransfer to Startup Circuits)

10.

Standby Bus Keowee Feeder Breakers, 4b SKI and SK2, Control Circuitry Notes:

a.

2 per bus.

b.

1 primary and 1 secondary* for each breaker.

c.

1 primary and 1 secondary* on the same breaker.

• A primary circuit includes the closing coil and one trip coii. a secondary circuit includes only one trip coil.

3.7-14 A

e d r.n S

'os.

117, 1n 7, 1 n1