Text

Application for Amend to License DPR-54,consisting of Rev 1 to Proposed Amend 147,changing Electrical Distribution Sys. Design Basis Repts,Response to NRC Question from 861125 Telcon & Summary of Changes Encl
	ML20212B378
Person / Time
Site:	Rancho Seco
Issue date:	12/19/1986
From:	Julie Ward; SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Miraglia F; Office of Nuclear Reactor Regulation
Shared Package
ML20212B386	List: ML20212B378; ML20212B420;
References
	JEW-86-968, TAC-63030, NUDOCS 8612290232
	Download: ML20212B378 (53)
	v • d • e

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gd SMUD SACRAMENTO MUNICIPAL UTILITY DISTRICT O P. o. Box 15830, Sacramento CA 95852-1830,(916) 452-3211 AN ELECTRIC SYSTEM SERVING THE HEART OF CALIFORNIA JEW 86-968 December 19, 1986 Director of Nuclear Reactor Regulation Attention: Frank J. Miraglia, Jr.

Director PWR-B Division U S Nuclear Regulatory Commission Washington DC 20555 Docket 50-312 Rancho Seco Nuclear Generating Station Unit #1 License No.DPR-54 PROPOSED AMENDMENT 147, REVISION 1

Dear Mr. Miraglia:

By letter dated October 2, 1986, the District submitted to the Commission Proposed Amendment No. 147 and further stated that Revision 1 would be submitted to address additional changes to the electrical distribution system.

The October 2, 1986 letter stated that Revision 1 would be submitted by November 14, 1986.

However, the District held a meeting with the NRC on November 11 and 12, 1986 to facilitate the NRC review of the design and to explain the additional proposed modifications.

In this review meeting, the District stated that Revision 1 would be submitted by December 15, 1986.

Proposed Amendment No. 147, Revision 1 is a complete resubmittal except as indicated below, of the material in the October 2, 1986 letter plus the revisions due to the planned modifications to the i

inverter power supply system and the undervoltage/overvoltage l

protection system.

All of the Technical Specification changes are discussed in detail in Enclosure 1 which is the Description of Proposed Changes, Associated Safety Analysis, and the "No Significant Hazards Evaluation". is the Proposed Technical Specifications.

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RANCHO SECO NUCLEAR GENERATING STATION : 14440 Twin Cities Road, Herald, CA 95638-9799;(209) 333 2935 i

Frank J. Miraglia December 19, 1986 To assist in the review, the District is providing design information that supports this proposed Technical Specification amendment. Also, all revisions to the October 2, 1986 submittal have been indicated by revision bars.

The enclosures include the following information: -

Summary of Diesel Generator Modification and Present Status of Emergency Power; -

Design Basis Report (DBR) Revision 7 for ECN A-3748, - the installation of the TDI diesel generators, the associated i

building and supporting systems; -

a)

Description of the Electrical Distribution System at Rancho Seco; b)

DBR Revision 8 for ECN A-3660, expansion of the electrical distribution system including tie-in of the new diesel generators; c)

DBR for ECN R-1045 - modification to 4160 volt bus overvoltage and undervoltage alarm and trip relaying schemes; and d)

DBR for ECN-0955 - modifications to i

the inverter power supply system. -

A comparison of the TDI diesel system and electrical tie-in designs to the latest NRC rqquirements of the Standard i

Review Plan (SRP) in NUREG-0800; 1 -

A Fire Hazards Analysis Report (FHAR) for the diesel generator building; -

Three revised electrical drawings -

remaining drawings in October 2, 1986 submittal did not change. -

Response to NRC question from a November 25, 1986 conference call.

i i

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Frank J. Miraglia December 19, 1986 The testing program will satisfy the refueling outage and ten year testing requirements of this proposed amendment.

The next testing interval will be the cycle 8 refueling outage for the refueling cycle testing and the next ten year testing will be performed in approximately ten years from the and of the current extended outage.

The diesel fuel oil storage tanks are protected from corrosion by a coating inside and outside the tank surfaces and by the station cathodic protection system.

However, the station cathodic protection for the new diesel fuel oil storage tanks requires an upgrade in order to conform to the latest standards.

This long term corrective action will be completed by December 31, 1987.

The District has decided to install the TDI diesel generators and implement changes associated with its electrical distribution system during the current extended outage.

Therefore, NRC approval of proposed amendment is required prior to startup.

Pursuant to 10CFR50.91(b)(1), the Radiological Health Branch of the California State Department of Health Services has been informed of this proposed amendment by mailed copy of this submittal.

Since this is a revision to Proposed Amendment No.147, no additional license fee is required.

If you have any questions concerning this submittal, please contact Mr. Ron Colombo of my staff at Rancho Seco Nuclear Generating Station.

I Sincerely, i

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D General Manager, Nuc j

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ENCLOSURE 1 DESCRIPTION OF PROPOSED CHANGES.

ASSOCIATED SAFETY ANALYSIS. AND THE "NO SIGNIFICANT HAZARDS EVALUATION" t

J

FACILITY CHANGE SAFETY ANALYSIS PROPOSED AMENDMENT 147 REV. 1 LOG NO. 760 REV. 3 Dgsettettgel Proposed Amendment 147 consists of changes and additions to the Rancho Seco Technical Specifications to permit operation of two TDI diesel generators in the essential electrical system, the revision to the inverter power supply system and the undervoltage/overvoltage protection system.

BR!sgg igt Cbgeggi The safety analysis /50.59 review for ECN R-0955, ECN R-1045, ECN A-3660 and ECN A-3748 determined that Technical Specification changes were required for these Mods.

Eygiugtigg god D3 sis igt ggfgly Eindings1 The following is a discussion of each Technical Specification change.

The changes are divided into five groups or sections depending on the type of change.

Each section lists the existing specification, the new specification, and a discussion of the change.

Each section also includes a safety analysis and a no significant hazards consideration for the changes.

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1.

3.7.1.D.

Emergency diesel generators A and B are operable and at least 35.000 gallons of fuel are in each storage tank.

Bases:

All of the normal power supply to plant auxiliarv loads is provided through the two unit auxiliary transformers connected to the generator buses.

Emergency power for the nuclear service loads is obtained from two on-site diesel generators.

The 35 000 gallons of fuel stored in each storage tank permit operation of the two diesel generators for seven davs.

Ued EEEELitcatigni 3.7.1.F.

Two' separate and independent diesel generator trains (train A is both diesel generators A and A2. train B is both diesel generators B and B2) are operable each with:

1.

Separate day tanks containing a minimum volume of 65 percent of tank capacity (265 gallons) of fuel for each A and B and 50 percent of tank capacity (315 gallons) of fuel for A2 and B2.

2.

A separate fuel storage system containing a minimum usable volume of 35.000 gallons of fuel for each A and B and 42.000 gallons of fuel for each A2 and B2.

3.

A separate fuel transfer pump for each engine of a train.

Danen:

All of the normal power supply to plant auxiliary loads can be provided through the two unit auxiliary transformers connected to the generator buses.

Emergency power for the nuclear service loads is ob'tained from two on-site diesel generator trains (train A is both diesel generators A and A2. train B tu both diesel generators B and D2).

The 35.000 gallons of fuel stored in each storage tank permit operation of the diesel generators A and b for seven davn.

The 42.000 gallons at fuel stored in each

storage tank permit operation of the diesel generators A2 and 82 for seven davs.

DiscusgLggi This change adds the two new TDI diesel generators A2 and 82.

Diesel generators A and A2 (one old and one news comprise train A and diesel generators B and B2 (one old and one now) comprise train B.

All diesel generator specifications are written using this train approach to simplifv the required limiting condition for operation for the operating staff.

This is a conservative approach since there are aniv limited instances where a safety function cannot be provided by only one old diesel generator per train.

The requirements for the day tanks and the fuel transfer pumps for each diesel generator are new additions to the specification.

These support systems are present1v required to be operable by plant procedures.

This change is consistent with the recommendations of Generic Letter 84-15.

E>1 sting Sgec(ficettgqi 2.

i 3.7.1.K.

The interconnections between 480 volt switchgear 3A and 3A2. and 3B and 3B2 are operable.

Ngw Seegifigatiggi N/A DiscusgLggi This specification has been proposed to be deleted.

This reouirement was originally added to reflect the Cvcle 7 interim power supply configuration.

Buses 3A2 and 3B2 will be powered by the new TDI diesel oenerators and will no longer require the interconnect.

3.

gnistieg Saggifigatigot 3.7.1.E.

Plant batteries are charged and in service.

3.7. Bases

The set of four 125 volt DC control panelboards (SOA.

SOD. SOC. SOD) and the set of two 125 volt DC control panelbaards (SOA2. SOB 2) are arranged so that loss of one bus will not preclude safe shutdown or operation of safety features systems.

Durino periods when one plant batterv is de eneroined for tout or maintenance. the associated 125 volt DC bus can be supplied from its batterv charoer.

U2M EREciflGG iget t

3.7.1.G.

Nuclear Service batteries BA. BB, BC. IBD, BA2, BB2. BC2 and BD2, which supply vital 125 volt buses SOA, SOB. SOC, SOD, SOA2, SOB 2, SOC 2, and SOD 2 are charged and in service.

3.7 Bases

The set or eight 125 valt DC control panelboards (SOA.

SOB, SOC. SOD. SOA2 SOB 2, SOC 2.

and SOD 2) are arranged so that loss of one bus will not preclude safe shutdown or operation of safety features systems.

During periods when one plant batterv is de-energized for test or maintenance, the associated 125 voit DC bus can be supplied from its batterv charger.

D12S9321001 Proposed Amendment 135 dated June 13, 1986 revises Specification 3.7.1.E shown to 3.7.1.G (above) without batteries BC2 and BD2 and buses SOC 2 and SOD 2.

This change adds batteries DC2 and BD2 and buses SOC 2 and SOD 2.

These batteries and buces are being added to support loads being added to the electrical distribution svstem.

This change maintains consistency in the specifications by listing all nuclear service batteries and the vital buses thev supply.

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Egint109 EDES111gatiggi N/A i

Ngu $gggt[Lge(tegt 1

Table 3.14-1 i

FIRE DETECTION INSTRUMENTS FOR SAFETY SYSTEMS j

i Minimum Operable j

Zone Instrument Location Heat Flame Smoke 105 Diesel Generator Building O

3 o

106 Diesel Generator Duilding O

3 6

i, 3.14.3.1 m.

Dienel Generator Buildino (Zone 105) i l

n.

Diesel Generator Building (Zone 106) i i

i i

i

[

3.14-2 INSIDE BUILDING FIRE HOSE STATIONS

- - - - _ - _ _ = = - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - -

ID No.

Location

_ _ _ _ _ _ _ _ _ = - - - - - -

III Diesel Generator Building Hose Stations FPHS-D-OO1 Train A Engine Room Elevation O' FPHS-D-OO2 Train A Control Room Elevation O' FPHS-D-OO3 Train A Mezzanine Elevation 18'6" FPHS-D-OO4 Train B Enoine Room Elevation O' FFHS-D-OO5 Train B Control Room Elevation O' FPHS-D-OO6 Train B Mez=anine Elevation 18' 6"

Diggggsiggi These changes add the fire detection instruments. the sprinkler systems. and the fire hose stations in the new diesel generator building.

These are additions to the specifications that provide fire protection features for portions of redundant systems important to safe shutdown e

as described in the Rancho Seco Fire Hazard Analysis Report.

5.

E31st1D9 59ecifigat get i

3.7.1.F.

Two out of three batterv chargers are operable for 125 voit DC buses "A"

and "C".

and "B"

thru "D".

3.7.1.G.

One out of two batterv chargers are operable for each 125 VDC bun "A2" and "B2."

Da59D Each redundant pair

("A" and "C",

"B" and "D")

of safety features actuation and reactor protection 125 volt DC buses has a standbv batterv charger in addition to a battery charger for each bus.

Thu 125 volt DC buses "A2" and "D2" each. has a standbv batterv charger.

Loss of oower from one batterv charger per pair of redundant DC buses of for DC bus "A2" or "B2" has no significant consuouence nince a standbv battery charoer is

available.

In addition. each 125 volt DC bus can continue to receive power from its respective battery without interruption.

Ucw Enesiilsat1901 3.7.1 H.

Each vital 125 valt DC bus SOA. SOB, SOC, SOD.

SOA2. SOB 2, SOC 2.

and SOD 2 shall have its normal batterv charger aligned to it.

Baseg Each redundant pair

("A" and "C".

"B" and "D")

of the eight 125 volt DC control buses (SOA and SOC. SOB and SOD. SOA2 and SOC 2, and SOB 2 and SOD 2) has a standby battery charger in addition to its normal battery charger.

On the loss of power from one batterv charger per pair the standby battery charger is put in service.

However, the standby charge can be aligned in place of its normal charger for only 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months because the standby battery charge is powered from a different diesel generator than the normal battery charger.

There are potential interactions after 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months that could occur upon the loss of off-site power and a single diesel generator failure.

This situation has not been analyzed but by limiting the time this configuration could exist, the probability of occurrence is sufficiently low to justify limited coeration in this condition.

Olgcuggiggt This change adds the battery chargers for vital 125 volt DC buses SOC 2 and SOD 2 which are not presently in the specifications.

The change is revised to only address the normal nuclear service batterv chargers required for reactor criticality and does not address the installed spare batterv chargers.

The change in designation for vital buses (A.B.C,D,A2.B2 vs. SOA, SOB, SOC, SOD, SOA2.

SOD 2, SOC 2, SOD 2) is addressed in proposed amendment 135 dated June 13, 1906.

This requirement on the standbv charger is addressed in specification 3.7.2J.

6.

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Nsw Sensifisati901 3.28 IDL Diegel Ggagtatgt Cgettgl Eggm Essential

- Venti tetten system egaticab(LLiv ennLLEcbtLity This specification applies to the operability of the TDI Diesel Generator Control Room Essential Ventilation System.

Qbjggtiye To assure that this system will be able to perform its design function.

S eELilEBtL90 E

3.28.1 Both TD1 Diesel Generator Control Room Essential Ventilation trains shall be operable at all times except as noted in 3.28.2 and 3.28.3.

3.28.2 With one TDI Diesel Generator Control Room Essential Ventilation train inoperable, demonstrate the operability of the remaining train.

Restore the inoperable train to operable status within 15 davs or be in at least hot shutdown within six hours and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

3.20.3 With both TDI Diesel Generator Control Room Essential Ventilation trains inoperable, restore at least one inoperable train to operable status within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months or be in at least hot shutdown within six hours and in cold shutdown within the followino 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

With one inoperable train restored to operable status, follow 3.28.2.

DaS99 The TDI Diesel Generator Control Room Essential Ventilation Svstem is required to provide cooling whenever the temperature in the control room reaches 122 F to protect reouired electrical comoonents.

DLMEU2Hl908 This new specification is added to assure operability of this ventilation avstem.

The ventilation system is recuired to provide coolino tar the electrical comoonents in the TDI Diesel Generator Control Room and not human Habitahi1itv constderat ons.

Safgty 6931y313 Igc Itgms in Sggtigg 11 The addition of the TDI diesel generators and the modification of the electrical distribution system.

results in a two train, two diesel generator per train limiting condition for operation power-system.

The District has reviewed this modification in accordance with 10 CFR 50.59 and determined that it required a change in the technical specifications. but was not an unreviewed safetv question.

A review of the Licensing documents for Rancho Seco show the following:

1.

The Bases for Technical Specification 3.7.

69ElliaCY EleEttical Systems states "The auxiliarv electrical power systems are arranged so that no single failure can inactivate enough safety features equipment to jeopardize plant safety."

2.

USAR section 8.2.3.4 gigglg Eailurg Agalygis fgc tb2 09G19dC 59CYicy Sygtgm. states

"...a single fault within the system, with postulated loss of offsite power combined with a design basis accident. does not preclude the reactor protective system. safety features actuation system, and the safety features equipment from performing their safety function."

tc Powet states 3.

USAR section 14.1.2.8 Loss of Elect i

b that "The unit is designed to withstand the effects of load re_tection or loss of all ac power.

Emergencv systems are described in Section 0.2.3."

Dased on this review, it was concluded that the design basis for the emergency power system is that a single failure of the system (including diesel generators) will not preclude the reactor protection system and safety feature system from performing their intended safety function.

The loads on the new diesel generators were evaluated to determine the effects of loss of ono diesel generator and associated power distribution system in the two diesel generator per train configuration.

The systems interaction evaluation included a review of system components with regard to their power supplies and whether failure of components within a system could escalate or aggravate an uvent or prusent confuqing information to the control room operators (i.e..

failure of one diesel generator in a train would not cause confusion or an unacceptable plant configuration).

The evaluation found that the diesel generators and associated power distributton uvstems for each train wer e independent and that no unacceptable interactions exist.

The following three sets of electrical loads were identified as system interactions.

Each of these cases were individually evaluated and no adverse system interactions were identified.

1.

The Eteege Etgtectign Ciccuits gf Eiging and Tubing Cganected te ewsi ttacy Eeequatet eusga Ie: sis and E:3191 These pumps are powered from the new diesel generators GEA2 and GEB2 while the freeze protection circuits are powered from the old diesel generators GEA, GEB MCC's S2A1 and S2B1.

These circuits will not cause system failure.

2.

Ibs C9DtE91 C1Ecu11 19c the UniD Essdwatst eump IuEbiDg 1sglatigD yelvs 30Y:295bD1 The MOV is powered from the old diesel generator GED, MCC S2B1, while the EFIC initiated close signals are powered from batteries off the new diesels GEA2 and GEB2.

This is not an interaction but a single failure which is addressed in the EFIC Design Basis Report (see Proposed Amendment 152 submitted December 5,

1986).

Additionally, the scenario would have happened even in a

single diesel generator per train system.

Byd ggen Mggitqting Analytet Eanels 164dM0s, 64dMBl.

3.

t These panels are supplied by either the A2 and D2 diesel generators while the hydrogen sample pumps are supplied by either A or D unit, respectively.

However, based on failure analyses of each individual power supply to each hydrogen monitor system, the hydrogen monitors will go downscale to zero.

This same downscale reading would result even if each system was fed by a single power source.

Hence, there is no confusing informati6n presented to the control room operators.

The DDR and Systems Interaction Study show that the 4 Diesel Generators and associated electrical systems are load independent and that the safety related loads powered by the Diesel Generators are redundant.

i.e..

GEA2 and GED2 are redundant and GEA and GED are redundant.

Dased on this the Dianel Generator combinations available are not only GEA and GEA2 or GED and GED2 for the two train configuration discussed in Technical Specifications, but also GEA and GED2 or GED and GEA2.

Dased on this the District in taking a conservative approach, 2 trains with 2 diesel generators por train (GEA and GEA2, GED and GED2).

However, for emergency situations 4 diesel generator combinations are available; GEA and GEA2 GED and GED2, GEA and GED2, and j

2

GEB and GEA2.

Based on this review the District concludes that this modification does not change the single failure requirements in USAR Chapter 8 or Technical Specification 3.7 Bases because redundancy of trains and system independence is still maintained.

It also does not reduce the margin provided in the accident analysis i

of USAR Chapter 14 because the additional capacity will support required safety related loads.

Basta igt Ug SLgelfLqant Ugtetds DeletmlecLLgn igt items Le Se El lGG ll' e

i The proposed change does not involve a significant hazards consideration because operation of Rancho Seco in accordance with this change would not:

(1) involve a significant increase in the probability

}

or consequences of an accident previously evaluated.

This modification does not significantly

]

alter the accident analysis in Chapters 8 and 14 of the USAR.

The modification of the electrical j

distribution system was designed to meet single failure criteria and withstand the effects of load i

rejection.

The systems interaction evaluation concluded that a failure of one diesel generator and p

associated poner distribution system would not introduce any unacceptable interactions or any failures in the remaining electrical distribution I

with its train.

Therefore, this change does not increase the probability or consequences of an accident.

(2) create the possibility of a new or different kind of accident from any previously analyzed.

The i

accident analysis in Chapter 14 of the USAR is not changed because the additional capacity unsures'.

that the power distribution system will support

.l required safety related loads.

The systems

'l interaction review shows that no new or different failures modes were created.

This modification i

does not therefore create the possibility of a new or different kind of accident.

(3) involve a significant reduction in a margin of I

safety.

The design basis for the emergency power system is that a single failure of the system j

(including diosul generators) will not preclude the l

reactor protection system and safety features syntum from performing their safety function.

The i

modification of the emergency power system does not l

change this basis.

Based on the systems interaction review and the dusign basis documents l

I

this change will not reduce the margin of safety.

The-modification to the emergency power system will provide redundant emergency power sources for the control room, TSC, and NSEB essential HVAC systems.

It will also provide additional capacity for future loads while ensuring that the existing emergency power system is not overloaded.

This therefore increases the existing margin of safety.

The emergency power system at Rancho Seco is based on a dual train (A and B) concept.

The existing diesel generators (A and B) primarily support ECCS loads.

With the addition of the new diesel generators (A2 and B2) the dual train-concept is maintained.

The ECCS loads are still on A and B, with A2 and B2 supporting HVAC loads, loads required by NUREG 0737 modifications, AFW/EFIC loads and other loads due to modifications to the plant.

This change therefore does not involve a significant reduction in the margin of safety.

t i

e Y

Eastten 11 - Ghaneen te the inyattet Eetent Sunalz System Egist(qq SagcLiteetigni 3.7.1.H.

Three out of four inverters S1A. S1B, S1C, and-S1D. and both inverters SLA2 and S1B2 are operable for 120 volt AC vital bus power.

Bases-3.7:

Sufficient redundancy is available with any three of the four 120 volt AC vital power buses (S1A. S1B, S1C. S1D) in service such that reactor safety is assured.

Every reasonable effort will be made to maintain all safety instrumentation in operation.

Following criticality, continued operation with inverters out-of-service as stated in Specification 3.7.1.H is governed by the individual LCOs for the components powered by the out-of-service inverter.

Ugw ggggifigatiggi 3.7.1.I.

Nuclear service inverters S1A2, S182, 51C2, and S1D2, and static switches HSTA3. H8TB3, H8TC3 and H8TD3, are operable for 120 volt AC vital bus power.

3.7.2.K.

Nuclear service inverters and static switches as listed in 3.7.1.1 shall be operable except should one inverter or static switch become inoperable for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .-the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

A static switch shall not be aligned to the backup source in place of an operable nuclear service inverter except during switching periods.

If more than one nuclear service inverter or static switch as listed in 3.7.1.1 should become inoperable.

within one hour take action to place the reactor in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Bases-3.7:

Four nuclear service inverters (S1A2. S192. S1C2. and S1D2) and static switches (HOTA3, HOTD3. HOTC3. and HOTD3) are required to be operable to power the 120 volt AC vital buses.

The nuclear service inverters are power from diesel generators A2 and D2 and the static switches are powered from diesel cenerators A and B.

This desion ensures that upon loss of an inverter or a single diesel oenerator the 120 volt AC vital buse=s will continue to receive power and that there are no system 1

1

interactions.

One nuclear service inverter or static switch is permitted to be inoperable for up to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

The static switch is only used as a backup for the inverter.

It is not permitted to be used when an inverter is operable except for switching period because it receives power from the nuclear service 480 V buses and there is no battery backup available.

Discussioni This change identifies the nuclear service inverters in the NSEB as the power sources for the 120 volt AC vital buses in the Auxiliary Building and the NSEB.

It also identifies the static transfer switches which provide an independent vital 480 volt AC backup source for each nuclear service inverter.

The existing specification allows one inverter to be out of service indefinite 1v.

The new specification requires that all the listed inverters be operable for startup and defines the amount of time inverters can be inoperable prior to shutting down the plant.

SAFETY ANALYSIS FOR ITEMS IN SECTION II:

Systems, Subsystems, Components Affected NSEB inverters SlA2, SlB2, SlC2, and SID2 presently supply vital 120V ac power to their associated inverter buses CIA 2-1, SlB2-1, SIC 2-1 and SID2-1.

This modification relocates the power sources of the Auxiliary Building inverter buses SlA, S1B, SIC, and SID from their dedicated inverters to the NSEB inverters of the same channels. This power source reassignment affects the loading of the NSEB inverters, their associated batteries and battery chargers, and in addition, the loads served by inverter buses S1A, SlB, SlC, and SlD.

Safety Functions of Affected Systems / Components and Effects of Safety Functions Batteries BA2, BB2, BC2, and BD2 and the associated battery chargers provide 125V de power to the NSEB vital 125V de buses SOA2, SOB 2, SOC 2, and S0D2.

The loads on these de buses include NSEB inverters SlA2, SlB2, SlC2, and SID2. The reassignment of the power sources for the Auxiliary Building inverter buses (SlA, SlB, SlC, and SID) to the NSEB inverters of the same channel increases the actual load on the NSEB inverters and subsequently on the associated batteries and battery chargers. The NSEB batteries, battery chargers and inverters have adequate capacity to supply the additional loads.

The District has verified that the backup ac power supply, regulating transformer and cable sizes are satisfactory for load capacity and voltage regulation. The sizing ensures that acceptable voltage levels will be maintained from the inverters or the backup supplies.

Analysis of Effect on Safety Functions e

This modification does not change the assignments of individual loads on their respective inverter buses.

It changes only the power sources to the Auxiliary Building inverter buses. The design change and the associated calculations verify that adequate power is available at the assigned sources and acceptable voltage levels are maintained feeding either from the inverters or the backup sources. This design change improves the availability and reliability of the power supplied to the Auxiliary Building inverter buses without any detrimental affects on the power supplied to the NSEB inverter buses. This design will provide two paths of standby ac power to each inverter bus backed with the second diesel generator of the same train. One path is through the standby battery charger, vital 125V de bus and inverter; the second path is through the voltage regulating transformer to the vital 120V ac bus.

Additionally, a systems interaction study of the "Two Diesel Generator Electrical Train Design (ERPT-E0179)* was performed and results confirm that there is very good "intrattain load separation" of electrical loads. The study concluded that no unacceptable system interactions were noted in cases where plant systems are supplied by both diesel generators in an electrical train.

Two additional failure modes are introduced by this modification.

They are f ailures of the static switch or manual bypass switch.

These failures meet the single failure requirements of the USAR and are additions to the failure

SAFETY ANALYSIS FOR ITEMS IN SECTION II: (Continued)

Analysis of Effect on Safety Punctions (Cont.)

modes that do not change the bases in the USAR.

The District considers that the transferability of the inverter bus to the standby power source more than compensates for these 2 additional failure modes.

Summary The changes covered by this modification represent improvement over the existing arrangement regarding the reliability and availability of power supplies to vital 120V ac buses SlA, SlB, SlC, and SID.

The District has verified the following:

(1) NSEB inverters SIA2, SlB2, SlC2, and SID2 can carry the additional loads assigned to buses SIA, S1B, SIC, and S1D, as the result of this design change.

(2) Batteries BA2, BB2, BC2 and BD2 have adequate capacity to supply the loads assigned to 120V ac buses SlA, SlB, SIC, SlD, SlA2-1, SIB 2-1, SIC 2-1, and SID2-1.

(3) Circuit breakers of the vital 120V ac system, affected by this design change, are properly coordinated.

(4) Cable sizes are satisfactory for ampacity and voltage regulation, and the sizing ensures that acceptable voltage levels will be maintained supplied from the inverter or the backup power supply.

USAR Section 8.2 i s impacted by this modification. Sub-section 8.2.2.7 and Figure 8.2-4 will be modified to reflect this design change. Based on the 2

discussion above, the District has determined that this is not an Unteviewed Safety Question.

Basis for No Significant Hazards Determination for Items in Section II:

The proposed change does not involve a significant hazards consideration i

because operation of Rancho Seco in accordance with this change would not (1) involve a significant increase ira the probability or consequences of an accident previously evaluated. This modification does not change the accident analysis in Chapters 8 and 14 of the USAR.

The modification increases the availability of the inverter buses by providing two diesel backed paths for power to each inverter.

Therefore, this modification does not increase the probability or consequences of an accident.

(2) create the posaibility of a new or different kind of accident from any previously analyzed. The accident analysis in the USAR is not changed by this modification.

It returns the vital 120 VAC power system to a 4 t

-. -. - ~. _

Basis for No Significant Hazards Determination for Items in Section II: (Cont.)

inverter configuration while providing an additional power path to each inverter. Therefore, this modification does not create the possibility of a new or different kind of accident.

(3) involve a significant reduction in a margin of safety. This modification increases the availability of the inverter buses.

It also provides a reliable inverter system capable of supporting the vital 120 VAC loads.

This modification therefore does not involve a significant reduction in the margin of safety.

i j

i i

I

EREllEn ill - GhAQREE ig the Qvgagliagg/_Un_dervoltagg P,y_gtgglign_

Ermite 1.

Egisting Egecificatiget l

TABLE 3.7-1 VOLTAGE PROTECTION SYSTEM RELAY TRIP VALUES

-=.

_ __=-

UNDERVOLTAGE RELAYS 4160 BUS VOLTS (SECONDS) NOTE 2 3

- _ _______lYOLIS1___ -

Trip Set Point 3771 !38 (Note 1) 98% of set point 3695 8.2 t 0.82 90% of set point 3394 5.2 i O.52 70% of set point 2640 3.1 1 0.31 0% of set point O.

1.5 t 0.15

- - = - -

OVERVOLTAGE RELAYS 4160 BUS VOLTS (SECONDS) NOTE 2 (VOLTS)

=____________________

Trip Set P'oint 4580 146 102% of set point 4672 7.2 10.72

= = _ _ _ _ - - --

=_______________

NOTE 1 - The relay voltage values shown have been converted by the PT ratio (40:1) for review convenience NOTE 2 - For bus tripping an additional O.5 time delay must be added.

NOTE 3 - The delay times shown are based on an initial of 4160 volts.

bus voltage I

I i

TABLE 3.7-2 e

= _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

f:

Minimum l

Total Number Channels Channels Action t

Functional Unit Of Channels To Trip OPERABLE (Note 1) b e

I G

undervoltage 3/ Bus 2/ Bus 2

A

[;

h t.

Overvoltage 3/ Bus 2/ Bus 2

A k

h i'.'

M 9

EREllGG 111 - GheG921 kg the Orgtvettegg[Undgrvottage P etectign t

Ermlem Egistiog SgecLiicatiggi TABLE 3.7-1 VOLTAGE PROTECTION SYSTEM RELAY TRIP VALUES EQUIVALENT TIME DELAY UNDERVOLTAGE RELAYS 4160 BUS VOLTS (SECONDS) NOTE 2 3

lVOLISl_______--__--_-__

Trip Set Point 3771 138 (Note 1) 98% of. set point 3695 8.2 i O.82 90% of set point 3394 5.2 + 0.52 0.31 70% of set point 2640 3.1 e

0% of set point O.

1.5 ! O.15

g- - g -----

- = -

OVERVOLTAGE RELAYS 4160 BUS VOLTS (SECONDS) NOTE 2

__--__-__---_______1VO61SL____________________________

Trip Set Point 4580 146 8

102% of set point 4672 7.2 10.72 NOTE 1 - The relay voltage values shown have been converted by the PT ratio (40:1) for review convenience NOTE 2 - For bus tripping an additional O.5 time delay must be added.

NOTE 3 - The delav times shown are based on an initial bus voltage of 4160 volts.

TABLE 3.7-2 Minimum Total Number Channels Channels Action Functional Unit Of Channels To Trip OPERADLE (Note 1)

Undervoltage 3/ Bus 2/ Bus 2

A Overvoltage 3/Duu 2/ Bus 2

4

, 651190 Etgiemenig Action A --With the number of OPERABLE channels one less than the total Number of' Channels operation may proceed provided both of the following conditions are satisfied:-

~

a.

The Inoperable channel is placed in the tripped condition within one hour.

b.

The Minimum Channels OPERABLE requirement is met; however. one additional channel may be bypassed for surveillance testing.

Note 1:

The above table is not applicable when the plant is in cold shutdown.

Bgggsi The voltage protection system is designed to isolate the nuclear service buses from the startup transformers when the bus voltage exceeds the allowable operating limits of the equipment.

The allowable operating range for the 4160 volt nuclear service buses is 3733 to 4626 volts-and 397 to 521 volts for the 480 volt nuclear service buses.

This corresponds to a switchyard voltage range of 215 to 244 KV.

This range of switchyard voltage encompasses the normal operating range of 221 to 239 KV.

U953 SDSSifiSal19Di S'

TABLE 3.7-1 VOLTAGE PROTECTION SYSTEM RELAY TRIP VALUES EQUIVALENT TIME DELAY UNDERVOLTAGE RELAYS 4160 BUS VOLTS (SECONDS) NOTES 1

______________________________JY96IS1__________________________

A.

Definite 3771 38 5.0 ! O.5 Time Delay Trip (Note 1)

Set Poin' (Drop Out)

B.

Inverse 3771 t 30 N/A Time Delay Trip Set Point (Drop Out) 70 Percent of Set 2640 1 27 3.0 t 0.5 Note 1 - For bus tripping. an additional O.5 second timo delay must be added.

TABLE 3.7-2 (Note 1)

=-------------------------------

=

Total No. of Minimum Functional Number of Relavs/

Channels Channels Action Unit Channelg Chaquel Io It g OEE888LE i

Under-3/ Bus 2

2/ Bus 2

A voltage 6CIJON SIBIEMENIS Action A - With the number of OPERABLE channels one less than the total Number of Channels. operation may proceed until performance of the next required CHANNEL FUNCTIONAL TEST provided the Inoperable Channel is placed in the tripped condition within one hour.

Note 1:

The table is not applicable when the plant is in cold shutdown.

Basesi The voltage protection system is designed to isolate the nuclear service buses from the startup transformers before the voltage drops below the allowable operating limit of the equipment.

The undervaltage protection for the 4160 volt nuclear service buses is 3771 + 38 volts.

N This corresponds to a nominal switchyard voltage range of 219 KV.

Discuggiggi The overvoltage protection was deleted to prevent automatic diesel generator start due to transient overvaltage conditions (i. e.

overvoltage conditions occurring with the starting of the reactor coolant pumps or the occurrence of high grid voltage of short duration).

This will prevent unnecessary challenges to the plant's safety features system in the 4160 V buses.

Also added is a definite time delay, undervoltage trip relay in each trip channel parallel with the existing relays within each 4160 V bus.

i I

2.

.Egistigg Egggifigatiggi.

Table 4.1-1 INSTRUMENT SURVEILLANCE REQUIREMENTS Channel Description Check Test Calibrate Remarks

_=

57.

Voltage Protection S(1)

(1) Compare voltmeter readings a.

Undervoltage M

R b.

Overvoltage M

R c.

Time Delay M

R MEM EEgelficatign 57.

Voltage Protection S(1)

(1) Compare voltmeter readings a.

Undervoltage M

R b.

Time Delay M

R Digggggiggi j

This revision deletes the monthly surveillance requirement associated with the overvoltage relay which i s being deleted f rom Table 3.7-1.

l l

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m.,_

_ ~, _.. _ _,.... _., _,.. _. -., _., _.,. -.,,.... _... _..,.., _

SAFETY ANALYSIS FOR ITEMS IN SECTION III:

Systems, Subsystems, Components Affected The primary system affected is the electrical distribution system (USAR Section 8.2) which encompasses the 4160.VAC, 480 VAC, 120 VAC and 125 VDC voltages.- Each voltage is used in its own unique power distribution scheme, however, all function together to supply the vital plant electrical loads.

This modification is confined to the 4160 VAC distribution scheme (USAR Section 8.2.2.4).

The 4160 VAC vital distribution scheme is comprised of nuclear service buses S4A, S4B, S4A2 and S4B2. These buses have independent and redundant electrical schemes, whose normal power sources are two different switchyard ring buses. The power from the ring buses is supplied to S4A, S4A2 and S4B, S4B2 through separate startup transformers. Normally S4A, S4A2 is supplied from startup transformer No. 1, and S4B, S4B2 is supplied from startup transformer No. 2.

Either startup transformer is capable of supplying either set of vital buses. The transfer of S4A, S4A2, S4B or S4B2 from one startup transformer to another can only be done manually. There is no automatic transfer of power supplies between the buses. Each bus is provided with its own emergency diesel generator, which automatically starts and picks up the bus loads upon loss of bus voltage from the normal power supply.

All the components in the facility modifications associated with this

. modification are Quality class 1 and Seismic Category I, including all installed cabling and raceways.

The relays, transducers and cabling associated with the modifications are environmentally and seismically qualified to IEEE 323/344.

There are no adverse effects from this facility change on other power sources within the Electrical Distribution System.

Effects on Safety Punctions

.This facility change provides enhanced control (alarm only instead of trip) of bus voltages and prevents bus trips from overvoltage conditions. Currently, requirements are to trip the 4160 V Class 1 busses when they are in an overvoltage condition.

The decision to alarm only for overvoltage conditions instead of trip is based on the need to reduce the probability of inadvertent actuation of the Standby Diesel Generator from overvoltages that are transient in nature.

It will also give the operator an opportunity to bring the Class 1, 4160 ESF bus voltage to the acceptable limit by following plant operating procedures.

If the operator'cannot reduce the overvoltage to the normal operating range of the 4160 V Class 1 bus, the operator must start the diesel generator, parallel it with the offsite power source, reduce the load on the 4160V ESP buses to the allowable limit of diesel generator loading, and then manually trip the offsite power circuit breaker. The operator must transfer from offsite power to diesel generator before 4626V ESP bus voltage (244KV Switchyard voltage) is reached.

SAFETY ANALYSIS FOR ITEMS IN SECTION III: (Continued)

The high voltage alarm is set at 4500 volts. The allowable operating range for 4160 V Class 1 buses is 3733 to 4626 volts, which corresponds to a switchyard voltage range of 215kV to 244kV. This range of switchyard voltage encompasses the normal operating range of 221 to 239kV.

4500 volts at the 4160 V Class 1 bus corresponds to a switchyard voltage of 237.5KV.

The operator will start taking action at 4500 V and completes transferring loads to diesel generator before the bus voltage reaches 4626 V.

For undervoltage protection the total number of protection channels is 3 per bus and the number of relays per channel is 2.

Both undervoltage relays I

ITE-27N and ITE-27 in each trip channel are connected to the same bus potential transformer. Output contacts that open when the input voltage drops below the relay dropout setting are connected in series to operate an auxiliary relay. The auxiliary relays are deenergized for an undervoltage detection by either ITE-27N or ITE-27.

The auxiliary trip relays and bus tripping logic is exactly the same as the existing scheme; that is the contacts from the auxiliary relays are arranged in a two-out-of-three logic.

This logic string is used to operate a bus unicading relay with a 0.5 sec.

time delay upon energization. The 0.5 sec. time delay is used to prevent an accidental bus unloading when the logic circuit is initially energized. The ITE-27 relay is used for first level of undervoltage (UV) protection, loss of offsite power (70% of trip setpoint or less). The ITE-27N relay is used for the second level of UV protection, long time degraded bus voltage (98% of trip setpoint).

Analysis of Effects on Safety Functions A single failure of any of the following new devices (voltage transducers and undervoltage relays) installed per this modification will not prevent the scheme from operating properly or cause it to operate when it is not required. Overvoltage conditions will be mitigated by the operator.

The two-out-of-three logic used in the design, to detect an undervoltage condition allows a single failure of the previously mentioned undervoltage relays without any effect on the operation of the system.

Summary This modification is an operational enhancement to the Electrical Distribution System and is bounded by the Licensing Design Basis.

Failure modes were analyzed and it has been determined that thete are no significant failures to compromise plant safety. No adverse impact on nuclear safety has been identified and no Unreviewed Safety Question is involved.

l Basis for No Significant Hazards Determination for Items in Section III:

The proposed change does not involve a significant hazards consideration because operation of Rancho Seco in accordance with this change would not i

Basis for No Significant Hazards Determination for Items in Section III:(Cont.)'

(1) involve a significant increase in the probability or consequences of an accident previously evaluated. The elimination of the overvoltage trip reduces the probability of standby diesel generator actuation due to transient overvoltage conditions while providing enhanced control (alarm instead of trip). Therefore, this modification does not increase the probability or consequences of an accident.

(2) create the possibility of a new or different kind of accident from any previously analyzed. This modification is an operational enhancement and is within the USAR design basis. Therefore, this modification does not create the possibility of a new or different kind of accident.

(3) involve a significant reduction in a margin of safety. This modification does not change the switchyard voltage allowable operating range and it reduces the probability of standby diesel generator actuation. Therefore, this modification does not involve a significant reduction in the margin of safety.

l t

E=51190 IV - Ade101sitative Cbm09esi 1.

Egisting Spegifiggliggi 3.7.1.C.

One 6900 volt reactor coolant pump motor bus is energized.

09W SDESifiSati901 N/A Discussiggi Specification 3.7.1.C has been proposed to be deleted since this specification is already addressed in Specification 3.1.1.1.

This change is consistent with the overall format of the Technical Specification and eliminates a redundant requirement.

2.

Egisting Sgggifigatiggi 3.7.2.E.

The essential nuclear service electrical buses, switchgear, load shedding, and automatic diesel start systems shall be operable except as provided in C above and as required for surveillance testing.

UEW 59ESif1SBli901 If N/A Discussioni This specification has been proposed to be deleted.

The requirements for the buses, switchgear, load shedding and automatic diesel start systems are addressed in Specifications 3.7.1.D, 3.7.1.E, 3.7.1.F, and 3.7.2.

This change is consistent with the overall format of the specifications.

E:l sting Sgecificatigni 3.

i 3.7.5 The voltage protection system trip setting shall be as stated in Table 3.7-1.

3.7.6 Voltage Protection System Limiting Conditions A.

Startup and operation are not permitted unless the minimum requirements and action statements of Table 3.7-2 are met.

B.

In the event the number of protective channels falls below that listed in Table

m 3.7-2, the plant will be brought to a. hot shutdown within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months .

New SEEEiiigatiggi 3.7.3 The voltage protection system trip setting shall be as stated in Table 3.7-1.

3.7.4 Voltage Protection System Limiting Conditions A.

Startup_and operation are not permitted unless the minimum requirements and action statements of Table 3.7-2 are met.

B.

In the event the number of protective channels falls below the listed in Table 3.7-2.

the plant will be brought to a hot shutdown within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months .

D1559521901 I

This changes the numberine of these specifications only, i.e..

3.7.5 to 3.7.3 and ~3.7.6 to 3.7.4.

Existing Specification 3.7.3 is being incorporated into 3.7.2 and

.i existing specification 3.7.4 is being changed to 3.1.1.7.

4.

Egistieg Sggcificatiggi 4.6.6 The pressurizer shall be tested as follows:

A.

The pressurizer water level shall be determined to be within its limi ts at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

B.

The power supply for the pressurizer heaters shall be demonstrated OPERABLE at least once per 18 months by using the gluclear Service Bus to energize the j

heaters.

Ugw Sessifisatigos 4.5.2.2.C.The pressurizer shall be tested as follows:

1.

The pressuriner water level shall be

[

determined to be within its limits at

{

least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

2.

The power supply for the nuclear service i

backed pressurizer heaters shall be demonstrated OPERABLE at least once per l

18 months by using the Nuclear Service Bus to energize the heaters.

t

~,~e-e

.e-...~4 4

y m-----r--

.----,,--,-.,,-----v

-~

4.5. Bases

The operabilitv of the nuclear service bus backed pressurizer heaters is demonstrated by energi:ing the heaters once per 18 months.

Di359551901 This~ change moves this specification from the Emergency Power System Periodic Testing section to the components tests section.

It also adds. clarification to identify the specific pressurizer heaters to be tested.

This change enhances the format of the Technical Specifications.

E isting Sgecificationsi 5.

t 3.7.1.B.

Two 220 KV lines'are in service.

3.7.1.I.

Both startup transformers, No. 1 and 2, are in service.

New Spegifigaliggi 3.7.1.A.

At least two 220 KV lines are in service.

3.7.1.C.

Both startup transformers, No. 1 and No.

2, are in service.

91359551901 This change renumbers these specifications to be consistent with the other changes to this section.

It also clarifies the requirement for two 220 KV lines to make it clear that more than two lines may be in service.

i 6.

Egigiigg ggggifigatiggi

~

3.7.1.J.

The switchyard voltage is 215 KV or above.

Uew 59esifisaii901 3.7.1.B.

The switchyard voltage is 219 KV or above.

91559551901 l

This change corrects an error in the voltaae at which the reactor can be brought critical.

The undervoltage trip setpoint listed in Table 3.7-1 results in an i

equivalent 216.5 KV setpoint (3771 138 volts on the 1

4160V Bus).

Based on this, the reactor cannot be brought critical without the switchvard voltage above 216.5 KV.

E:l sting Sgecificatigni i

7.

3.7.1.A.

All nuclear service buses, nuclear service switchgear, and nuclear service load shedding systems are' operable.

Ngg Sgggificatiggi 3.7.1.D.

Nuclear services 4160V buses 4A, 4A2, 4B, and 4B2 are operable.

3.7.1.E.

Nuclear services 480V buses 3A, 3A2, 3B, 3B2, 2A1, 2B1, 2A3, 2B3, 2A4, and 2B4 are operable.

Disgyggiggi This is a clarification to specifically identify _which nuclear services buses are required to be operable.

The nuclear service switchgear and load shedding systems are deleted from this specification.

They are part of the nuclear service buses and without them being operable, the bus is not operable.

E>1 st i ng Sgec i fi c ati gni 8.

i 4.31 Bases:

The system is automatically started when the temperature in the NSEB Switchgear Room exceeds 95 F, except upon loss of offsite power; in which case, the system can be manually started by the operator.

New Sgecificatigg 4.31 Bases:

The system is automatically started when the temperature in the NSEB Switchgear Room exceeds 95 F.

Discusgiget The modified electrical distribution system will now au'tomatically start the system without operator action upon loss of offsite power.

I 9.

EEiStiOg Sgggificaliggi 4.10 Bases:

During an SFAS and a loss of offsite power, the "B"

Train of essential HVAC equipment is sequenced to automatically start upon its actuation signals approximately 6 minutes after the diesel generator breaker closes.

The "A" Train of HVAC equipment can be manually energized and started as before following automatic application of all essenti al loads.

New Saecifisat1901 4.10 Bases:

The filtering system is automatically started and the normal system isolated when the radiation level or when the chlorine level increases.

Disegssiggi This section is deleted from the bases.

The modified electrical distribution system will now automatically start the system without operator action upon loss of offsite power.

Safety Anglysis igt items in Sectigg IVE The changes listed above are administrative changes.

They are made to improve the overall Technical Specification editorial consistency and format, clarify requirements and correct errors.

Basis [gt Ug Siquiticqqt Hagatds Detetmi nati ggi The proposed change does not involve a significant hazards consideration because operation of Rancho Seco in accordance with this change would not:

1) involve a significant increase in the probability or consequences of an accident previously evaluated.

This enhanced clarity should decrease the potential for unacceptable consequences or accidents..

These are editorial and administrative changes which do not increase the probability or consequences of an accident.

2)'

create the possibility of a new or different kind of accident from any previousiv evaluated. A new or different kind of accident will not be created due to these editorial and administrative changes.

These administrative changes do not create the possibility of a new or different kind of accident.

3) involve a significant reduction in a margin of safety.

These editorial and administrative changes ensure.that the Technical Specifications address proper plant conf.iguration following the installation of the new diesel generators and will preserve the margin of safety.

Therefore, the administrative changes will not reduce the margin of safety.

1 3

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f r

fi$

4 e

J f

V 4

t i

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EEEllGQ M - 1GEtte1R EC A_dditige tg Eutygillgact R,gggicamenig and 6teLietLQns 1.

Existing Snecificatign:

3.7.4 The pressurizer shall be OPERABLE with at least 126 kw of pressurizer heaters.

With the pressurizer inoperable due to inoperable emergency power supplies to the pressurizer heater either restore the inoperable emergency power supply within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in HOT SHUTDOWN within the following 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

Bases-3.7:

The requirement that 126 KW of pressurizer heaters and their associated controls being capable of being supplied with electrical power from an emergency bus provides assurance that these heaters can be energized during a loss of offsite power condition to maintain natural circulation at HOT SHUTDOWN.

S eqLiicatiget New R

3.1.1.7 The pressurizer shall be operable, except when the reactor is in cold shutdown, with 3 groups of heaters in two separate banks that are capable of being powered by the diesel generator trains.

With the heaters in one bank inoperable, either restore the bank to operabl e status within 15 days or be in at least hot standbv within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in hot shutdown within the following 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

.With the heaters in oath banks inoperable, either restore one bank to operable status within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months or be in at least hot standby within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in hot shutdown within the following 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

l Bases-3.1:

l There are 3 groups of heaters in bank 2, and 3 groups of heaters in bank 3 that are capable of being powered by the diesel generator.

Each set of the 3 groups of i

heaters has a nominal rating of 126 kw which provides assurance that these heaters can be energized during a loss of offsite pcwer condition to maintain natural l

l circulation at HOI SHUIDOWN.

l l

Discussion:

1 Specification 3.7.4 is renumbered to 3.1.1.7 (3.7.4 and Bases from 3.7 deleted, 3.1.1.7 and Bases for 3.1 added).

This chance makes this item consistent with the

~

r overall format of the Technical Specifications.

The revision to this specification:

1)

More clearly identifies the requirements for operability of. pressurizer heaters by specifically identifying the number of heaters required.

2)

Reduces the time permitted in a limiting condition for operation (LCO)'to be consistent with Specification 3.7.2.B.and 3.7.2.E.

This change more clearly reflects the evaluation made by the NRC in their Mav 1,

1980 letter which evaluated the Districts actions to satisfy NUREG 0578.

2.

E>1Lsting Sgeq((Lcetigni 3.7.2.A.

One 220 KV line shall be fully operational and capable of carrying nuclear service and auxiliary power except as specified in D belou.

New Spegifigaliggi 3.7.2.A.

At least two 220 KV lines shall be in service except should all but one 220 KV line be removed from service the operability of the remaining 220 KV line shall be demonstrated by performing surveillance requirement 4.6.1.A within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 8 ha'urs thereafter and surveillance requirement 4.6.3.A.4 is performed within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

If at least two 220 KV lines are not in service within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Disgyssiggi This change incorporates the recommendations of Generic Letter 84-15.

It provides clear requirements for number of lines in service and defines the actions required if this requirement is not met.

The present Technical Specifications allow indefinite operation with only one 220 KV line in service.

The new specification limits the tirte onlv one 220 KV line is in service.

3.

Enisting Specifigatigni 3.7.2.C.

Both diesel generators shall be operable except that from and after the date that one of the diesel generators is made or found to be inoperable for any reason, reactor

operation is permissible for the succeeding 15 days provided that during such 15 days the operable diesel generator shall be load tested daily and both startup transformers are available.

If the diesel is not returned to service at the end of 15 days, the other diesel will be started and run with at least minimum load continuously for an. additional 15 days.

If at the end of the second 15 days the diesel is not returned to service, the reactor shall be brought to the cold shutdown condition within an additional 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

New Spegificatiggi 3.7.2.B.

Both diesel generator trains shall be operable except should one diesel generator train become inoperable the operability of at least I.

two 220 KV lines circuits shall be demonstrated by performing surveillance requirement 4.6.1.A within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months thereafter and.surveillince requirement 4.6.3.A.4 is performed within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months and at least once per 7 days thereafter.

If the diesel generator train is not restored to operable status within 15 days, the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Disgussiggi This change incorporates the recommendations of IE Information Notice 84-69, Supplement I,

" Operation of Emergency Diesel Generators."

It eliminates the 15 day period where the operable diesel is run continuously with minimum load.

Running the diesel with minimum load may reduce its operability.

The surveillance requirements are revised to reduce the number of starts and more clearly define the operability of offsite sources to be consistent with the recommendations of Generic Letter 84-15.

i 4.

Existing Specificatign-N/A New Sgegificatiggi 3.7.2.C.

At least two 220 KV lines and both diesel generator trains shall be operable except should all but one 220 KV line and one diesel generator train both become inoperable l

the operability of the remaining 220 KV line i

i

~

shall be demonstrated by performing surveillance requirement 4.6.1.A within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months thereafter, and the_ diesel generator train shall be demonstrated to be operable by performing surveillance requirement 4.6.3.A.4 within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

If either the 220 KV line or the diesel generator train is not restored to operable status within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

With the diesel generator train restored t

7o operable status within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , follow 3.7.2.A.

With the 220 KV line restored to service within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , follow 3.7.2.B.

Digggggiggi

,4

_The new specification is being added to clearly identify the requirements if only one 220 KV line and one diesel generator train are operable.

It also incorporates the recommendation in Generic Letter 84-15.

i 5.

E:l stino Spec _ificatigni i

3.7.2.D.

If the plant is separated from the system

[

while carrying its own auxiliaries, or if all 220 KV lines are lost, continued reactor operation is permissible provided that one

?*

emergency diesel generator is started and run l

continuously until a transmission line is restored.

New Spegifigatiggi 3.7.2.D.

At least two 220 KV lines shall be in service except should all 220 KV lines become inoperable the operability of the two diesel generator trains shall be demonstrated by performing surveillance requirement 4.6.3.A.4 within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

This surveillance requirement 1

I does not have to be performed if the two diesel generator trains are already in service.

If at least one 220 KV line is not returned to service in 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

With one off-site circuit restored to service within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , follow 3.7.2.A.

l Diggyssiggi i

The existing specification allows continuous operation with the loss of all 220 KV lines provided one diesel generator is running continuously.

The change I

incorporates the recommendations of Generic Letter 84-15 and'IE Information Notice 84-69 by requiring restoration of one 220 KV line within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months and eliminating the requirement to continuously run a diesel generator.

E i sting Speci ficatigni 6.

E 3.7.3 If both diesel generators become inoperable, the. unit shall be placed in the cold shutdown condition.

New Spegificgtigni 3.7.2.E.

Both diesel generator trains shall be operable except should both trains be inoperable the operability of at least two 220 KV lines shall be demonstrated by performing surveillance requirement 4.6.1.A within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months thereafter.

If one diesel generator train is not restored to operable status within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

With one diesel generator train restored to operable status within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months , follow 3.7.2.B.

Disguggiggi g

This change identifies the specific actions required if both diesel generator trains are inoperable.

This change is consistent with the recommendations in Generic Letter 84-15.

}

7.

Egisting Sgecificatign-1 3.7.2.B.

Both startup transformers shall be in service j

except that one will be sufficient if during J

the time one startup transformer is inoperable, the associated diesel generator is started and run continuously.

New Spegifigailggi 3.7.2.F.

Both startup transformers shall be in service except should one startup transformer become inoperable the operability of at least two 220 KV lines shall be demonstrated by perf orn.ing surveillance 4.6.1.A within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and at least once per 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months thereafter and the diesel generator trains shall be demonstrated with 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

If startup transformer no. 1 is not restored to operable status within 24 i

hours. the reactor shall be in hot shutdown i

?

within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and'in cold shutdown within the following 205 hours0.00237 days 0.0569 hours 3.38955e-4 weeks 7.80025e-5 months .

If startuu transformer no. 2 is not restored to operable status within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in

- cold shutdown wit.hin the following 205 hours0.00237 days 0.0569 hours 3.38955e-4 weeks 7.80025e-5 months .

Diggyspiggi This change providet operability requirements for the startup transformers that eliminates the requirement to-continucusiv run a diesel generator.

This i s consistent with the recommendations in Generic Letter 84-15.

8.

EListi no Egeci ficatigni N/A New Egesifigatiggi 3.7.2.G.

If both startup transformers become inoperable, within one hour take action to place the reactor in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 205 hours0.00237 days 0.0569 hours 3.38955e-4 weeks 7.80025e-5 months .

Diggyssiggi The existing specifications do not address loss of both I

g startup transformers.

This change defines the actions required if both startup transformers are inoperable.

This change is consistent with the recommendations of Generic Letter 84-15.

The 205 hour0.00237 days 0.0569 hours 3.38955e-4 weeks 7.80025e-5 months time is consistent with the Districts November 7, 1985 revised request for exemption to some requirements of 10 CFR 50, App.

R.

/

9.

Egisiing Sgggifigatiggi 3.7.2.G.

Both sets of nuclear services buses 4A, 4A2, and 4B, 4B2 are operable except that one set of nuclear service buses (4A, 4A2 or 4B. 4B2) may be removed from service for not more than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months provided that all equipment on the 4

other set of nuclear service buses is operable.

l Ngg ggggifigatiggi 3.7.2.H.

Nuclear service buses as licted in 3.7.1.D and j

3.7.1.E shall be operable except should one nuclear service bus become inoperable for l

greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months 3 the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in l

I i

r--

--wy-y-my,,-- w - w-gpr w ww wwgrweryw-,~n,.y-wq.wy-yy,-+-w---wayv.m-e-,,wwww-eww--.wwm m my.g p w,wavi w w-wy e------in-e--wy vvw--erw-n-wy--w-m--mw w-in-r um w y-

)

cold shutdown within the.following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If more than one nuclear service bus as listed in 3.7..l.D and 3.7.1.E should become inoperable, within one hour take action to place the reactor in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Diggyssiggi This change more clearly defines the actions required if one nuclear service bus becomes inoperable.

It also defines the actions required if-more than one bus becomes inoperable.

This change is consistent with the format and intent of the other changes to the specifications.

10.

Egi sting Egeci ficatignt 3.7.2.F.

Nuclear service batteries are charged and in service except that one nuclear service battery may be removed from service for not more than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

Ngts ggggifigatiggi 3.7.2.I.

Nuclear service batteries as listed in 3.7.1.G shall be charged and in service except should one nuclear service battery become inoperable g#"'.

for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If more than one nuclear service battery as listed in 3.7.1.G should become inoperable, within one hour take action to place the reactor in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

2 Disgyssiggi This change defines actions required if one or more nuclear service batteries are out of service.

This change is consistent with the recommendations of Generic Letter 84-15.

d 11.

ggtstida gancificattent N/A i

mw=---,-rm--n-----~n-n-

-,m-r-=-------wv---

w-..m,-

NEW E9EEifigatiggi 3.7.2.J.

Nuclear service battery. chargers as listed in.3.7.1.H shall.be' operable except should one nuclear service battery have no battery charger for greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the 4

following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If a standby charger is aligned in place of its normal charger for greater that 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

If more than one nuclear service battery has no battery charger as listed in 3.7.1.H, within one hour take action to place the reactor in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

91259221901 This revision adds operability requirements for nuclear service battery chargers.

This revision incorporates the recommendations of Generic Letter 84-15.

12.

Enigting Sgegificatiggi 3.7.2.H.

If the switchyard voltage goes below 219KV, positive actions, within the District's procedures, will be implemented in an attempt to return the voltage to 219KV.

If the switchyard voltage goes below 217KV or remains below 219KV for 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months , one electrical division will be operated on its diesel generator independent of off-site power.

The other electrical division will be operated on off-site power with its associated diesel generator on standby status.

The switchyard voltage must be returned to 219KV within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

Switchyard voltage above 219KV will allow unrestricted plant operation.

Ued SDEEifigatiggi 3.7.2.L.

Should the switchyard voltage drop below l

219KV, positive actions, within the District's procedures, will be implemented in an attempt to return the voltage to at least 219 KV.

If the switchyard voltage goes below 219 KV, both l'

operable within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months bv performing diesel generator trains shall be demonstrated l

surveillance requirement 4.6.3.A.4.

Should the switchvard voltage not be restored above i

i k

i

219 KV within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , the reactor shall be in hot shutdown within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Qigguggiggi The change eliminates the requirement to continuously run a diesel generator.

The revised surveillance requirements are consistent with the recommendations of Generic Letter 84-15 and IE Information Notice 84-69, Supplement I.

13.

Egisting ggegifigatigni N/A NRW EnEElilEalieGi 3.27 NucLgat @etvicg (Lgchttcal Building Emetgengy dealtun Ventilatten and Bi t Cendilleeine System ennlicability This specification applies to the operability of the Nuclear Service Electrical Building Emergency Heating Ventilation and Air Conditioning System.

obiectlye To assure that this system will be able to perform its designed function.

SERElilCalieG 3.27.1 Both Nuclear Service Electrical Building Emergency Heating Ventilation and Air Conditioning trains shall be operable at all times except as noted in 3.27.2.

3.27.2 With one Nuclear Service Electrical Building Emergency Heating Ventilation and Air Conditioning train inoperable, restore the train to operable status within 7 days or be in at least hot standby within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in cold shutdown within following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

With both Nuclear Service Electrical Building Emergency Heating Ventilation and Air Conditioning trains inoperable, restore the trains to operable status within 3.5 days or be in at least hot standby within the next 6

hours and in cold shutdown within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

Bageg The Nuclear Service Electrical Building (NSEB) Emergency Heating Ventilation and Air Conditioning system is required to provide cooling to protect required electrical components in the NSEB.

Discuggigg-This new section is added to provide a LCO for the surveillances required by Specification 4.31.

It defines the operability requirements for the system to be consistent with Amendment 68 dated June 3, 1985 where the NRC stated that the system was required to be operable even though a LCO specification was not provided.

Since the system is now backed by the diesel generators during loss of offsite power, the time to restore the system to operable status it it is found to be inoperable has been increased from 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to 7 days for one train and 3.5 days for both trains.

This approach is consistent with the requirements of specification 3.13.3 on the Control Room /TSC Emergency Filtering System.

14.

Enigting Specificatiggi N/A New Specificatiggi 4.6.1 Offsite Power Sources A.

Each of the 220 KV lines required by 3.7.1.A shall be:

Determined OPERABLE at least once per 7 days by verifying correct breaker alignments and indicated power availability, and B.

Each Start-up Transformer required in 3.7.1.C shall be demonstrated OPERABLE at least once per refueling shutdown by transferring nuclear service buses as listed in 3.7.1.D from the normal startup transformer supply circuit to the alternate startup transformer supply circuit.

Bageg The operability of the 220 KV lines, the nuclear service 4160V buses, and the nuclear service 480V buses are demonstrated by verifying correct breaker alignments and 4

n,-

n,.,

v.

indicated power availability.

Surveillance 4.6.1.B can only be performed during a refueling shutdown when both diesel generator trains are operable or the core is flooded to 37 feet to ensure the required decay heat removal capability is available.

Disqugsiggi This new specification adds surveillance requirements to demonstrate the operability of the 220 KV lines and startup transformers required by Specifications 3.7.1.A and 3.7.1.C.

This is a new surveillance requirement since the existing specifications do not require a surveillance to demonstrate operability of the 220 KV lines or startup transformers.

15.

Egisligg Spegifigatiggi I

N/A New SEEci fi cati 901 4.6.2 Nuclear service buses required by 3.7.1.D and 3.7.1.E shall be determined to be OPERABLE at least once per 7 days by verifying correct breaker alignment and indicated power availability.

Digggggiggi c

This adds surveillance requirements to demonstrate the operability of the nuclear service 4160 V and 480V buses required by Specifications 3.7.1.D and 3.7.1.E.

This is consistent with the overall format of these technical specifications.

16.

Egigting Sgggifiggliggi 4.6.1 At intervals not to exceed one month, a test of the diesel generators will be performed to verify proper operation of these emergency power sources and associated equipment.

This test will be performed to assure that:

A.

Each diesel generator can be started from the control room.

B.

Each diesel generator can be synchronized with its associated 4160 volt nuclear service bus.

4.6.5 Diesel generator fuel oil supplv shall be tested as follows:

A.

During the monthly diesel generator test, the diesel fuel oil transfer pumps shall be monitored for operation.

B.

Once a month, quantity of the diesel fuel oil shall be logged and checked against minimum specifications.

The tests specified will be considered satisfactory if control room indication and/or visual examination demonstrates that all components have operated properly.

New E2egifigatiogi 4.6.3 Each diesel generator shall be demonstrated OPERABLE by verifying that both diesel generators in the train are OPERABLE (A and A2, B and B2).

Each diesel generator shall be demonstrated OPERABLE.

A.

In accordance with the frequency specified in Table 4.6-1 by:

1.

Verifying the fuel level in the day

tank, 2.

Verifying the fuel level in the fuel storace tank, a

~

3.*

Verifying the fuel transfer pump starts and transfers fuel from the storage system to the day tank, 4.*

Verifying the diesel starts from a manual signal and accelerates to a nominal 900 rpm for A and B and 450 rpm for A2 and B2.

The generator voltage and frequency shall be 4160 (1420) volts and 60 (tl. 2) Hz after the start signal.

(Note 1) 5.*

Verifying the generator is synchronized and operates with its full load of 2650 (1100) kw for A and B and 2475 (1100) kw for A2 and B2 for at least 60 minutes, (Note 1).

6.*

Verifving the diesel oenerator is aligned to provide emergency power to the nuclear services buses at the conclusion of the test.

.~ -- - -.., - ------- - ---,- - - -

r

Surveillance shall not be performed when a diesel generator train is not operable in accordance with TS 3.7.2.

Note 1:

All planned engine starts for the purpose of

.this surveillance testing may be preceded by an engine prelube period.

Further, all surveillance tests, with the exception of once per 184 days and 10-year duration test, may be preceded'by warmup procedures recommended by the manufacturer and may also include slow starting and gradual loading so that mechanical stress and wear on the diesel engine is minimized.

The testing performed once every 184 days shall include fast starting (less than or equal to 10 seconds).

Testing performed every refueling shutdown shall include fast loading.

Iable 4 6:1 t

DIESEL GENESAIOB IESI SGHEDULE Number of Failures in best:20 Yelid Iests*

Iest Eceguegev 1

At least once per 31 days 2

At least once per 7 days **

Criteria for determining number of failures and number of valid test shall be in accordance with Regulatory Position C.2.e of Regulatory Guide 1.108, Revision 1,

August 1977, where the number of tests and failures is determined on a per diesel generator basis.

For the purposes of this test schedule, only valid tests conducted after the license amendment issuance date shall be included in the computation of the "last 20 valid tests."

- This test frequency shall be maintained until seven consecutive failure free demands have been performed i

and the number of failures in the last 20 valid demands has been reduced to one or less.

Bgses The limi ting of the maximum load on the TDI diesel generators A2 and B2 to less than the qualified load of 3300 kw provides assurance that the crankshafts will stay within the proven limits for high-cycle fatigue cracks.

l

Diesel generators A2 and B2 will be loaded during surveillance testing to 1650 KW which provides assurance that the qualified load of 3300 KW will not be exceeded.

The 1650 KW loading is one half the.

qualified load and over twice maximum load of safety equipment during the loss-of-offsite power.

Discussiggi This change incorporates recommendations from Generic Letter 84-15 and IE Information Notice 84-69,_ Supplement 1.

These include the reduction of fast starts and test frequency based on failures.

The change more clearly identifies the requirements for demonstratin( the operability of the diesel generators.

17.

Ex i st i ng Sgeci fi cat i gni N/A New Sgggifigatiggi 4.~6.3.B By sampling at least once per 92 days the oil in each fuel oil storage tank and by sampling new fuel oil prior to addition to the storage tanks and verifying:

1.

A water and sediment content of less than or equal to.05 volume percent when tested in accordance with ASTM-D975-77, 2.

A kinematic viscosity at 40 C of greater than or equal to 1.9 but less than or equal to 4.1 when tested in accordance with ASTM-D975-77.

}

Distyssiggi This requirement is presently being performed by plant surveillance procedures even though the items were not

'in the specifications.

This is consistent with the i

requirements of Regulatory Guide 1.137, Fuel-Oil Systems For Standby Diesel Generators.

18.

Existing Sgegifigatiggi 4.'6. 2 During each refueling interval, a test of the diesel generators and emergency start circuits shall be performed to verify that these emergency power sources and associated i

equipment are operable by:

l

r A.

Simulating a loss of offsite power in conjunction with a safety features actuation signal, and:

1)

Verifying de-energi=ation of the nuclear. services buses and operation of the load shedding circuitry.

2)

Verifying the diesel starts from ambient condition on the auto-start signal.and energizes the nuclear services buses, and by verifying proper operation of the automatic load sequencing circuitry, including-manual closing of the A Train intertie breakers from.the Control Room and manual energi ation of the A Train essential HVAC from the Control Room.

The B Train intertie breakers are automatically closed and the B Train Control Room essential HVAC System is automatically energized.

The diesel generators will be operated for at least 5 minutes in this condition.

B.

Simulating a loss of offsite power and verifying that on interruption of the emergency power sources the loads are shed from the nuclear services buses in accordance with design requirements and d

that subsequent loading of the emergency power sources is through the automatic load sequencing circuitry.

The diesel generator will be operated for at least 5 minutes in this condition.

C.

Load testing the diesel generators for SFAS capacity.

4.6.3 Each diesel generator shall be given a thorough inspection at least biannually following the manufacturer's recommendations for this class of standby service.

Bases:

They assure the 3B, 3B2 Intertie breakers are automatically closed and the B Train Control Room esbential HVAC System is automatically energized.

The

]

3A-3A2 and 3B-3B2 interties are not required if the event is only a safety features actuation.

i l

l l

L

r' New Spegifigatiggi 4.6.3.C.

At each refueling shutdown, by:

1.

Diesel Generator Inspections a.

Subjecting the diesel generators A and B to an inspection in accordance with procedures prepared in conjunction with the maintenance recommendations provided by its manufacturer for this class of standby service.

6.

Subjecting the diesel generators A2 and B2 to an inspection in accordance with procedures prepared in conjunction with the maintenance and surveillance program recommended by the TDI Owners Group in " Design and Revalidation Report for Rancho Seco," Appendix II.

2.

Simulating a loss of off-site power in conjunction with a safety features actuation signal (Note 2), and a)

Verifying de-energization of the nuclear service buses and operation of the load shedding circuitry.

f. *.

b)

Verifying the diesel starts on the auto-start signal (Note 1),

energizes the nuclear service buses, verifying proper operation of the automatic load sequencing circuitry, and operates for greater than or equal to 5 minutes in this condition.

After energization, the steady state voltage and frequency of the emergency buses shall be maintained at 4160 (1420) volts and 60 (11.2) Hz during this test.

3.

Simulating a loss of off-site power and verifying that on interruption of the emergency power sources the loads are shed from the nuclear services buses in accordance with design requirements and that subsequent loading of the emergency power sources is through the automatic load sequencing circuitry.

The diesel generator will be operated for at least 5 minutes in this condition.

r~

4.

Verifying the diesel generator operates for at least 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

During the first 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months of this test, the diesel generator shall be loaded to 2750 (t100) kw for A and B and 2475 (1100) kw for A2 and B2 and for the remaining 22 hours2.546296e-4 days 0.00611 hours 3.637566e-5 weeks 8.371e-6 months of this test, the diesel generator shall be loaded to 2650 (1100) kw for A and B an't 2475'(1100) kw for A2 and B2.

Note 1 All planned engine starts for the purpose of this surveillance testing may be preceded by an engine prelube period.

Further, all surveillance tests, with the exception of once per 184 days and 10 year duration tests,_may be preceded by warmup procedures recommended by the manufacturer and may also include slow starting and gradual loading so that mechanical stress and' wear on the diesel

~

engine is minimi. zed.

The testing per, formed 0 include fast once everv 184'aays shal1 starting sless thad or equal to 10 seconds).

Testing performed overy refueling shutdown shall ' include f ast loading.

L Note 2 Prior to the performance'of this test the,"

diesel generators,sh511 'be operated at 2650 1 (100). kw for A Mid B and 2475 1 (100) kw for

~

A2 and B2 for I hour or until operating tempera,ture has stabilized.

dN Discussion:

This change expands and'clearlN identifies the requirements for load testing the' diesel generators.

This change incorporates,the recommendations in Generic Letter 84-15.

The Cycle. 7 testing requirements for the Control Room HVAC'a're also deleted 1 With the addition of the TDI diesel generators the Control Room HVAC will be automatically loaded in accordance with the District's commitment to meet NU, REG 0737, item III.D.3.4, Control Room Habitability.

19.

Egisting Specificaliggi N/A New SpgqLitcatigni 4.6.3.D.

At least once per 10 years, by starting all four diesel generators simultaneously and verifying that they accelerate to a nominal 900 rpm.+cr n and B and 450 rp;a for A2 and B2 within 10 seconds after the start signal.

The

generator voltage and frequency shall be 4160 (1420) volts and 60 (11.2) Hz within 10.0 seconds after the start signal.

4.6.3.E.

In lieu of performing 4.6.3.C.2 at least once per 10 years simulating a loss of off-site power in conjunction with a simulated SFAS, and 1.

Verifying de-energization of the nuclear service buses and load shedding from the nuclear service buses.

2.

Verifying the diesel starts on the auto-start signal, energizes the nuclear service buses with permanently connected loads, loads through the load sequencer and operates for greater than or equal to 5 minutes while its generator is loaded with the emergency loads.

After energization, the steady state voltage and frequency of the emergency buses shall be maintained at 4160 (142O) volts and 60 (11.2) Hz during this test.

3.

Verifying for the A and B diesel generators that all automatic diesel generator trips, except engine overspeed.

ground fault and generator differential, b,#,

and verifying for the diesel generators A2 and B2 that all automatic diesel generator trips, except engine overspeed, low lube oil pressure and generator differential, are automatically bypassed with an SFAS.

Basesi At least once per 10 years a diesel generator test will be performed simulating a loss of offsite power in conjunction with a simulated SFAS and loading of actual loads to the maximum extent possible without damaging plant systems (i. e.

use of recirculation flow or manual valving out of a system to protect plant components).

Discussient These specifications are added to demonstrate that all four diesel generator systems will start simultaneously and that they will accept actual emergency loads.

This incorporates the reco<nmendations of Generic Letter 84-15.

I

\\

r:

Safety-Eyaluatiga igt items La Sectign Mt These are changes to the operability and surveillance requirements.

In most cases the new requirements are more restrictive.

In some cases the requirements are less restrictive.

These are cases where the existing surveillance may actually degrade the operability of the system.

The requirements for cold fast starts of diesel generators are an example of this.-

The changes incorporate recommendations from Generic Letter 84-15

" Proposed Staff Actions to Improve and Maintain Diesel Generator Reliability", IE Information Notice 84-69, Supplement 1,

" Operation of Emergency Diesel Generators,"

and Regulatory Guide 1.137, " Fuel-Oil Systems for Standby Diesel Generators."

Basis igt Ng Significggt Magards Dgiermigatiget The proposed changes do not involve a significant hazards consideration because operation of Rancho Seco in accordance with this change would not:

1) involve a significant increase in the probability or consequences of an accident previously evaluated.

The changes are to the operability and surveillance requirements.

They add requirements for new systems, improve requirements for existing systems, and incorporate NRC recommendations.

The changes demonstrate the operability of required systems to ensure safe operation of the plant.

Therefore, these changes do not increase the probability or consequences of an accident.

2) create the possibility of a new or different kind of accident from any previously analyzed.

The changes demonstrate the operability and surveillance of critical plant systems.

The changes to the operability and surveillance requirements do not create the possibility of a new or different kind of accident.

3) involve a significant reduction in a margin of safety.

The changes improve operability and surveillance requirements and therefore preserve the margin of safety.

They will not reduce the margin of safety.

+

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A

v t e Letter Sequence Request
TAC:63030, (Approved, Closed)
Initiation Request, Request, Request, Request, Request, Request, Request, Request, Request Acceptance... Supplement, Supplement, Supplement, Supplement Administration Questions Answers Results Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval Other: A11745, Evaluation of DSR-48 Emergency Diesel Generator Crankshafts at Rancho Seco Nuclear Generating Station, ML19317G911, ML20086J905, ML20126J866, ML20126J973, ML20135E867, ML20149D631, ML20149F003, ML20196E677, ML20196E697, ML20206H162, ML20212B420, ML20215G661, ML20234C529, ML20234C558, ML20234D524, ML20234D615, ML20234D649, ML20235M565, ML20235Q511, ML20236L543, ML20236N639, ML20236S088, ML20237B265, ML20237B279
MONTHYEAR1987-11-09 [Table View]

ML20212B378

Text

Dear Mr. Miraglia:

3.7. Bases

3.7 Bases

4.5. Bases

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