ML15112A922

Amends 82,82 & 79 to Licenses DPR-38,DPR-47 & DPR-55, Respectively,Authorizing Changes in Tech Specs Re Auxiliary Electrical Sys & Emergency Power Periodic Testing

ML15112A922
Person / Time
Site:	Oconee
Issue date:	05/02/1980
From:	Reid R Office of Nuclear Reactor Regulation
To:
Shared Package
ML15112A923	List: ML15112A922 ML15112A924 ML15112A925
References
NUDOCS 8005210484
Download: ML15112A922 (20)

Text

lb UNITED STATES NUCLEAR REGULATORY-COMMISSION WASHINGTON, D. C. 20555 DUKE POWER COMPANY DOCKET NO.

50-269 OCONEE NUCLEAR STATION, UNIT NO. I AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 82 License No. DPR-38

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

A. The applications for amendment by Duke Power Company (the licensee) dated February 1, 1978, and June 12, 1978, as supplemented October 31, 1978, and August 22, 1979, comply with the standards and requirements of the Atomic Enerqy Act of 1954, as amended (the Act), and the Commission's rules and regulations set torth in 10 CFR Chapter I; B. The facility will operate in conformity with the applications, the pro visions 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 satis fied.

2. Accordingly, the license is anended 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.B Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 82 are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

so s 052 0u

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

FOR THE NUCLEAR REGULATORY COMMISSION Robert W. Reid, Chief Operating Reactors Branch #4 Division of Operating Reactors

Attachment:

Changes to the Technical Specifications Date of Issuance:

May 2, 1980

• oW UNITED STATES 4

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. 82 License No. DPR-47

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

A. The applications for amendment by Duke Power Company (the licensee) dated February 1, 1978, and June 12, 1978, as supplemented October 31, 1978,.and August 22, 1979, comply with the standards and requirements of the Atomic Enerqy 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 applications, the pro visions 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 satis fied.

2. Accordingly, the license is anended 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:

3.8 Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 82 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 REGULATORY COMMISSION Robert W. Reid, Chief Operating Reactors Branch #4 Division of Operating Reactors

Attachment:

Changes to the Technical Specifications Date of Issuance: May 2, 1980

UNITED STATES NUCLEAR REGULATORY-COMMISSION WASHINGTON. D. C. 20555 DUKE POWER COMPANY DOCKET NO. 50-287 OCONEE NUCLEAR STATION, LplT NO. 3 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 79 License No.

DPR-55

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

A. The applications for amendment by Duke Power Company (the licensee) dated February 1, 1978, and June 12, 1978, as supplemented October 31, 1978, and August 22, 1979, comply with the standards and requirements of the Atomic Enerqy 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 applications, the pro visions 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 reaulations and all applicable requirements have been satis fied.

2. Accordingly, the license is anended by changes to the Technical Specifications as indicated in the attachment to this license amendment and paraaraph 3.8 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. 79 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 REGULATORY COMMISSION Robert W. Reid, Chief Operating Reactors Branch #4 Division of Operating Reactors

Attachment:

Changes to the Technical Specifications Date of Issuance:

May 2, 1980

-ATTACHMENT TO LICENSE AMENDMENTS AMENDMENT NO. g TO DPR-38 AMENDMENT NO. py TO DPR-47 AMENDMENT NO. 79 TO DPR-55 DOCKETS NOS. 50-269, 50-270 AND 50-287 Revise Appendix A as follows:

Remove Pages Insert Pages 3.7-1 through 3.7-2 3.7-1 through 3.7-2 3.7-2T 3.7-3 through 3.7-8 3.7-3 through 3.7-9 4.6-1 through 4.6-3 4.6-1 through 4.6-3 Substantive changes on the revised pages are indicated by a marginal line.

3.7 AUXILIARY ELECTRICAL SYSTEMS Applicability Applies to the availability of offsite and onsite 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.

3.7.1 Except as permitted by 3.7.2, 3.7.3, 3.7.4, 3.7.5, 3.7.6, and 3.7.7, the reactor shall not be heated above 200OF unless the following conditions are met.

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

(b) Two independent onsite 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 4160 volt standby bus.

2. The second Keowee hydro unit; through the overhead path and breaker PCB9; the 230kV switchyard yellow bus; through the respective operating unit's start-up transformer or the aligned and connected alternate startup transformer. One start-up transformer may not be aligned to supply power to more than two units.

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

(d) The three 4160 volt Engineered Safety Features switchgear buses, three 600 volt load centers, and the three 600-208 volt Engineered Safety Features MCC buses shall be energized.

(e) For each unit, all 125 VDC distribution centers, diode monitors, diodes required to supply the unit's four 125 VDC instrumenta tion and control panelboards and the 120 VAC auxiliary control power panelboards shall be operable. The 125 VDC instrumentation and control batteries with an associated charger shall be oper able as follows:

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

2. For operation of any two units, ICA or 1CB, 2CA or 2CB, and 3CA or 3CB.

3.7-1 Amendments Nos.

82, 82 & 79

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

(f)

Both of the 125 VDC 230kV switching station batteries, with their respective chargers, distribution centers, and panel boards shall be operable.

(g)

Both of the 125 VDC Keowee batteries with their respective chargers and distribution centers shall be operable.

(h)

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

3.7.2 During hot standby or power operation, provisions of 3.7.1 may be modified to allow the following conditions to exist:

(a) One of the two independent onsite 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 power path is verified operable within one hour of the loss and every eight hours thereafter.

(b)

One 4160 volt main feeder bus may be inoperable for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

(c) One complete single string (i.e., 4160 volt switchgear, 600 volt load center, 600-208 volt MCC, and their loads) of each unit's 4160 volt Engineered Safety Features Power System may be inoper able for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

(d)

One or more of the following DC distribution components may be inoperable for periods not exceeding 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (except as noted in 3.7.2(e) and (f) below):

1.

One complete single string or single component (i.e., 125VDC battery, charger,.distribution center, and panelboards) of the 125VDC 230kV Switching Station Power System.

2.

One complete single string or single component (i.e., 125VDC battery, charger, and distribution center) of the Keowee 125VDC Power System may be inoperable provided the remaining string of Keowee is operable and electrically connected to an operable Keowee hydro unit.

3.

One complete single string or single component (i.e., 125VDC battery, charger, distribution center, and associated isolat ing and transfer diodes) of any units 125VDC Instrumentation and Control Power System.

4.

One 125VDC instrumentation and control panelboard and its associated loads, provided no additional AC buses are made inoperable beyond the provisions of 3.7.2.(a), (b), and (c).

(e) One battery each, from one or more of the following 125VDC systems may be simultaneously inoperable for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> in order to perform an equalizer charge after the surveillance reouirements of Specification 4.6.10.

3.7-2 Amendments Nos. 82, 82 & 79

3.7.2T (Temporary Technical Specification)

During hot standby or power operation, provisions of Tethnical Specification 3.7.1 and 3.7.2 may be modified on a one time basis to allow each of the two switchyard batteries to be removed from service for a period not to exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> in order to install upgraded (seismic design) battery racks. Whenever one of the two batteries is removed from service for installation of a battery rack, the other battery and its complete 125 VDC power string (charger, distribution center, and panelboards) must be operable.

When installation of the two racks is completed, this Technical Specification will expire and this temporary page should be removed from the Technical Specifications.

Amendments Nos. 82, 82 & 79 3.7-2T (Temporary)

1. 230KV Switching Station 125VDC Power System

2. Kteowee Hydro Station 125 VDC Power System

3. Each unit's 125VDC Instrumentation and Control Power System 3.7.3 In the event that the conditions of Specification 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, 3.7.6, and 3.7.7 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 placed 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 0 F 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 200oF 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 100kV circuit.

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

(b) The remaining Keowee hydro unit shall be connected 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 overhead transmission circuit.but generation to 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. Office of Inspection and Enforcement, 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:

Amendments Nos.

82, 82 & 79 3.7-3

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 100 kV transmission circuit shall be complately separate from the system grid and Wttaite non-safetym related loads.

(b) The reactor coolant Tays shall be above 525 F. Reactor coolant PUME power may be vgused to elevate the temperature from 500 F to 525 0in the case of restart.

If T decreases below 500aF, restart is not permitted by this specification.

(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 Office of Inspection and Enforcement, Region

h.

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 shall be submitted detailing the 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 are 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.

3.7-4 Amendments Nos.

82, 82 & 79

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

3.7.8 Any degradation beyond Specification 3.7.2, 3.7.4, 3.7.5, 3.7.6, or 3.7.7 above shall be reported to the Office of Inspection and Enforce aent, 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 per formed 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 Office of Inspection and Enforcement, 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 of AEC Criterion

17.

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

Capacity of AC Systems The auxiliaries of two units in hot shutdown (6.OMVa each) plus the auxiliaries activated by ESG signal in the other unit (4.8 MVa) require a total AC power capacity of 16.8 WVa. The continuous AC power capacity available from the on site power systems (Keowee hydro units) is 20 MVa (limited by transformer CT4) if furnished by the underground circuit or 30 MVa (limited by CT1 or CT2) if furnished through the 230 kV offsite transmission lines.

Capacity available from the backup 100 kV offaite 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 MVa, is adequate.

Amendments Nos. 82, 82 & 79 3.7-5

Capacity 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 ha adequate stored capacity (ampere-hours) to independently supply their required emergency loads for at least one hour.

One hour is considered 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. The following tabulation demonstrates the margin of installed battery charger rating and battery 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 [CA, XCB, or ICS

a.

600 amps each Battery [CA or [CB Capacity

b.

600 ampere-hours each (X -

1, 2, or 3)

Combined total connected loads

a.

Inrush (2 sec) -

1160 amps on both 125 VDC I & C buses XDCA and KDCB next 59 min. - 506 amps during 1st hour of LOCA

b.

516.9 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 ampere-hours Active load per battery

a.

Inrush (2 seconds) 130 amps during 1st hour of LOCA next 59 min. -

10 amps

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 features switchaear 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.

Amendments Nos. 82, 82 & 79 3.76

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, onsite Keowee hydro station or from several offsite sources via transmission lines which connect the Oconee station with the Duke Power system power distribution network.

Redundancy of DC Systems 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 the Unit 2 and Unit 3 or the 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.

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 tor 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 protective relaying,

b.

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

c.

Connect onsite power to Oconee from a Keowee hydro unit, or

d.

Restore offsite 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 Category I subsystems, each complete with an AC/DC power supply (charger) a battery bank, a battery/charger bus and a DC distribution center.

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

Amendments Nos. 82, 82 & 79 3.7-7

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

The 230 kV sources, while expected to have excellent availability, 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.wstation is under the direct control of the Oconee station and requires no offsite power to startup.

Therefore, an onsite backup source ot 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 hydro unit is verified within one hour by starting the unit and energizing the standby buses through the underground feeder circuit. This action is repeated once every eight hours thereafter until the Keowee hydro unit is restored to service and will provide additional assurance of the operability of the remaining unit.

Provisions have been.established for those conditions in which long term pre ventative maintenance of a Keowee hydro unit is necessary. 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 offsite 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 offaite 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.

Amendments Nos. 82, 82 & 79 3.7-8

A 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 Keovee units is spcept able since a Lee gas turbine will be started within one hour and will eneraize the standby buses through the dedicated 100 kV transmission line.

This period of time is reasonable to determine apd rectify the situation vhich caused the loss of both Keovee units.

In the event that none of the sources of offsite pover 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.

Amendments Nos.

82, 82 & 79

4.6 EMERGENCY POEMERIODIC TESTING Applicability Applies to the periodic testing surveillance of the emergency power sources.

Ob ective To verify that the emergency power sources and equipment will respond promptly and properly when required.

Specification 4.6.1 Monthly, a test of the Keowee hydro units shall be performed to verify proper operation of these emergency power sources and associated equip ment. This test shall assure that:

a.

Each hydro unit can be automatically started from the Unit 1 and 2 control room.

b.

Each hydro unit can be synchronized through the 230 kV overhead circuit to the startup transformers.

c.

Each hydro unit can energize the 13.8 kV underground feeder.

d.

The 4160 volt startup transformer main feeder bus breakers and standby bus breaker shall be exercised.

4.6.2

a. Annually, the Keowee hydro units will be started using the emergency start circuits in each control room to verify that each hydro unit and associated equipment is available to carry load within 25 sec onds of a simulated requirement for engineered safety features.

b. Promptly following the above annual test, each hydro unit will be loaded to at least the combined load of the auxiliaries actuated by ESG signal in one unit and the auxiliaries of the other two units in hot shutdown by synchronizing the hydro unit to the offsite power system and assuming the load at the maximum practical rate.

4.6.3 Monthly, the Keowee Underground Feeder Breaker Interlock shall be verified to be operable.

4.6.4 Annually, a simulated emergency transfer of the 4160 volt main feeder buses to the startup transformer (i.e., CT1, CT2 or CT3) and to the 4160 volt standby buses shall be made to verify proper operation.

4.6.5 Quarterly, the External Grid Trouble Protection System logic shall be tested to demonstrate its ability to provide an isolated power path between Keowee and Oconee.

4.6.6 Annually and prior to planned extended Keowee outages, it shall be demonstrated that a Lee station combustion turbine can be started and connected to the 100 kV line. It shall be demonstrated that the 100 kV line can be separated from the rest of the system and supply power to the 4160 volt main feeder buses.

Amendments 5os. 82, 82 & 79 6.6-1

4.6.7 Annually, it shall be demonstrated that a Lee station combustion turbine can be started and connected to the isolated 100 kV line and carry the equivalent of the maximu safeguards load of one Oconee unit (4.8 MVA) within one hour.

4.6.8 Annuafly, it shall be demonstrated that a Lee station combustion turbine can be started and carry the equivalent of the maximum safeguards load on one Oconee unit plus the safe shutdown loads of two Oconee units on the system grid.

4.6.9 Batteries in the Instrumentation and Control, Keowee, and Switching Station shall have the following periodic inspections performed to assure maximum battery life. Any battery or cell not in compliance with these periodic inspection requirements shall be corrected to meet the requirements within 90 days or the battery shall be declared inoperable.

a.

Weekly verify that:

(1)

The electrolyte level of each pilot cell is in between the minimum and maximum level indication marks.

(2) The pilot cell specific gravity, corrected to 770F and full electrolyte level, is > 1.200.

(3)

The pilot call float voltage is > 2.12 VDC.

(4)

The overall battery float voltage is > 125 VDC.

b.

Quarterly verify that:

(1) The specific gravity of each cell corrected to 770 F and full electrolyte level, is > 1.200 and is not less than 0.010 below the average of all cells measured.

• (2) The voltage of each cell under float charge is > 2.12 VDC.

(3) The electrolyte level of each connected cell is between the minimum and maximum level indication marks.

c.

Annually verify that:

(1) The cells, end-cell plates and battery racks show no visual indication of structural damage or degradation.

(2) The cell to cell and terminal connections are clean, tight and coated with anti-corrosion grease.

4.6.10 Annually, a one hour discharge service test at the required maximum load shall be made on the instrument and control batteries, the Keowee batteries, and the switching station batteries.

4.6.11 Monthly, the operability of the individual diode monitors in the Instru ment and Control Power System shall be verified by imposing a simulated diode failure signal on the monitor.

4.6-2 Amendments N s. 82, 82 & 79

4.6.12 Semiannually, the peak inverse voltage capability of each auctioneering diode in the 125 VDC Instrument and Control Power System shall be seasured and recorded.

Bases The Keowee lydro units in addition to serving as the emergency power sources for the Oconee Nuclear Station, are power generating sources for the Duke system requirements. As power generating units, they are operated frequently, normally on a daily basis at loads equal to or greater than required by Table 8.5 of the FSAR for ESF bus loads. Normal as well as emergency startup and operation of these units will be from the Oconee Unit 1 and 2 Control Room. The frequent starting and loading of these units to meet Duke system power requirements assures the continuous availability for emergency power for the Oconee auxiliaries and engineered safety features equipment.

It will be verified that these units will carry the equipment of the maximum safeguards load within 25 seconds, including instrumentation lag, after a simulated re quirement for engineered safety features. To further assure the reliability of these units as emergency power sources, they will be, as specified, tested for automatic start on a monthly basis from the Oconee control room.

These tests will include verification that each unit can be synchronized to the 230 kV bus and that each unit can energize the 13.8 kV underground feeder.

The interval specified for testing of transfer to emergency power sources is based on maintaining maximum availability of redundant power sources.

Starting a Lee station gas turbine, separation of the 100 kV line from the remainder of the system, and charging of the 4160 volt main feeder buses are specified to assure the continuity and operability of this equipment.

The one hour time limit is considered the absolute maximum time limit that would be required to accomplish this.

REFERENCE FSAR Section 8 Amendments Nos. 82, 82 & 79