ML20093J689

Proposed Tech Specs,Consisting of Change Request 446 Re Toxic Gas Isolation Sys Temporary Outage Time.Change Request Is Suppl 1

ML20093J689
Person / Time
Site:	San Onofre
Issue date:	10/18/1995
From:	SOUTHERN CALIFORNIA EDISON CO.
To:
Shared Package
ML20093J669	List: ML20093J665 ML20093J678 ML20093J689
References
NUDOCS 9510230358
Download: ML20093J689 (16)

Text

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DESCRIPTION AND SAFETY ANALYSIS OFPROPOSEDCHANGENPF-10/15-446(SUPPLEMENTJ1 This is a request to revise Technical Specification 3/4.3.2, " Engineered Safety Features Actuation System Instrumentation," Table 3.3-3, for San Onofre Units 2 and 3.

Units 2 and 3 Technical Specifications Existing Specifications:

Unit 2: See Attachment "A" Unit 3: See Attachment "B" Proposed Specifications:

Unit 2: See Attachment "C" Unit 3: See Attachment "D"

1.0 DESCRIPTION

OF CHANGES:

This amendment request is to make a change to Technical Specification (TS) 3/4.3.2, " Engineered Safety Features Actuation System Instrumentation," Table 3.3-3.

TS 3/4.3.2 includes the requirements for the minimum number of Toxic Gas Isolation System (TGIS) channels operable. This TS change request is to extend the allowed TGIS outage times during replacement of TGIS instrumentation.

Replacement of TGIS instrumentation is governed by Design Change Package 6933 (DCP 2/3-6933.00SJ).

This change adds a note to TS Table 3.3-3.

This note states-

"During construction for DCP 2/3-6933.00SJ Actions 14 and 15 will not be in effect.

Compensatory actions for the l

TGIS channels will be conducted in accordance with the j

Octoberf;18 J1995, Edison letter to the U.S. Nuclear Regulatory Commission."

PCN-4_46; required that either one channel of TGIS be available or the Units 2 and 3 control room be isolated during the construction period i

for TGIS instrumentation replacement.

In the event a TGIS channel cannot be restored cr the Centrol Rec Emergency Air Clean Up System I

fGREAGUS) cannot be initiated cr maintained in the i clation mcde of eper+t4cn due to equipment malfunction, it is acceptable to return the i

control room to the normal mode of ventilation for a limited time to restore control room air quality or repair th: ;;;cciated CREACUS 1

equipment. These periods when the control room will be in the normal mode of ventilation with TGIS unavailable will not exceed a cumulat;ve i

Si hours for all construction periods associated with TCIS l

inst:umentation replacemen.t{will;:belforf;contingencyfusefonlik LDuring these! peri ods Easj'ga's j watchUwil.1j: be{provided ito; mon itorifor stoxi.cl gas 1-l l

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2.0 BACKGROUND

2.1 TGIS The TGIS provides protective action for control room personnel from a toxic chemical release at or in the vicinity of San Onofre.

Two independent channels (Channels A and B) of instrumentation are shared by both Units 2 and 3 as a common system and are required for all modes of operation. TGIS analyzers monitor for high concentrations of Butane / Propane (hydrocarbons), Ammonia, and Chlorine gases.

Upon reaching the TS limit the TGIS isolates the common Units 2 and 3 control room and starts the Control Room Emergency Air Cleanup System (CREACUS). Manual TGIS actuation is also available in the control room if plant conditions require, or for testing. The toxic gas sources evaluated for San Onofre are (1) onsite releases due to equipment failure / transfer accidents and (2) offsite releases due to transportation accidents.

Each of these potential release sources is described below.

(1) Onsite Sources Ammonia is the only onsite toxic gas that the TGIS system is credited for in toxic gas events. The principal ammonia gas source onsite is the 9000 gallon ammonia tank.

Evaluated accidents include seismic ammonia tank failure, random ammonia tank failure (unanticipated tank failure), and ammonia tank accidents during ammonia transfer, including operator error.

(2)

Offsite Sources These include transportation accidents on Interstate 5 or the adjacent rail lines which result in releases of ammonia, chlorine, and Butane / Propane (hydrocarbon) gases.

2.2 Technical Specification TS 3/4.3.2, " Engineered Safety Features Actuation System Instrumentation," provides the requirements for the number of operable channels, trip setpoints, and response times for the Engineered Safety Features Actuation Systems, including TGIS.

TS 3/4.3.2, Table 3.3-3, requires two operable channels of TGIS gas analyzers, manual trip buttons, and automatic actuation logic.

Action 14 of Table 3.3-3 requires that with only one operable channel the inoperable channel be restored to operable status within seven days or isolate the control room and initiate and maintain CREACUS in the isolation mode of operation within six hours. Action 15 of Table 3.3-3 requires that with no operable channel initiate and maintain operation of CREACUS in the isolation mode of operation within one hour.

If CREACUS cannot be maintained in the isolation mode or a channel of TGIS restored to operable status within the specified intervals, then both San Onofre Units 2 and 3 must be shutdown.

3.0 DISCUSSION

3.1 Reason for the Proposed Change TGIS instrumentation replacement involves substantial modifications in the cabinet which houses both channels of TGIS. instrumentation.

It is expected that one channel of TGIS will be inoperable for approximately 22 days for replacement of the ammonia and butane analyzers.

Both channels of TGIS will then be maintained operable for approximately 7 to 30 days to allow for testing of the new instrumentation. Then the other channel of TGIS will be inoperable for approximately 22 days for replacement of its ammonia and butane analyzers.

The need for replacement of the TGIS instrumentation is described below:

A.

Obsolete Equipment

)

The TGIS panel was designed and fabricated with instruments procured in the early 1980s. Over the years, progress has been made in the field of analytical instrumentation, thus making the current TGIS ammonia and butane analyzers obsolete.

The original vendor of the ammonia and butane analyzers, Beckman Instruments, sold their analyzer division to Rosemount Analytical Inc.

Rosemount has subsequently discontinued manufacturing both the Model 400 Hydrocarbon Analyzer and the 865 Ammonia Analyzer currently used in the San Onofre TGIS, and spare parts for these analyzers are no longer readily available.

In some cases, spare parts are only available as substitutes requiring system modification.

B.

High Maintenance The ammonia analyzers are developing a poor maintenance record and have experienced several spurious trips. The existing ammonia analyzers have experienced problems of drifting low and bringing in the channel failure alarm.

The analyzer drift I

has been increasing and the maintenance costs associated with frequent calibration are significant. The drift has exceeded the 5% drift accounted for in the TGIS setpoint calculation i

several times in the last 3 years.

(In these cases the TGIS was evaluated by the San Onofre instrument out-of-tolerance program and addressed as necessary.)

The hydrocarbon analyzers, although not experiencing a drift problem, have also recently experienced more frequent maintenance activities. l J

~

The existing TGIS chlorine analyzers are operating properly and are still supported by the manufacturer, Wallace & Tiernan. These components have not become obsolete, and spare parts are available.

Therefore, the chlorine analyzers are considered acceptable and are not expected to require upgrade in the near term.

3.2 Basis for the Duration of the Proposed Change The TGIS is common to both units and is required for all modes of operation. The conctruction schedule for the ammonia and butane analyzer replacement is planned to consist of 43 shifts per channel, which is about 22 days of two 10-to 12-hour shifts per day, 7 days a week.

Replacement activities will be performed on one channel of TGIS at a time, with an approximate 7-to 30-day period following replacement of the first channel of instrumentation when both channels of TGIS will be operable to assure proper operation of the new instrumentation prior to replacement of the second channel of instrumentation. During construbtion~attivitiesithe"entirejTGISithannelsbbinbork'edjod;

+

befinoperableMConstructmmoniaMandjbutane/gropanei etecto@jyil_1 including;the1 chlorine,Ja d

ion activities required to replace a chantsel'of"TGIS'are not expected to affect or result in physical damage to any components in the remaining operable channel of TGIS except as described below.

Some periods of construction involve extensive cutting and welding work within the cabinet, which contains both channels of TGIS.

During these periods it is expected that the operable channel of TGIS may experience spurious actuations. During these periods the control room will generally be isolated with CREACUS initiated and maintained in the isolation mode and the operable TGIS channel will be in bypass. Control room isolation may be accomplished via either manual actuation of the TGIS system (pressing the trip button) or by manual operator actuation of the individual components actuated by TGIS.

(All TGIS actuated components can be operated from the control room area which is in the CREACUS boundary.)

Some of these periods of potential spurious actuation crc cxpected tefmay be of a lengthy duration (i.e., longer than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).

The San"On'ofre control room is not designed to be operated for extended periods while isolated with CREACUS operating.

(Toxic gas releases which the TGIS is designed to mitigate are expected to dissipate to acceptable levels in less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.) Over extended periods the control room air quality will degrade slowly and may become uncomfortable and, if prolonged long enough, uninhabitable.

Therefore, the control room cannot be placed in the isolation mode continuously for the entire construction period.

The instrumentation replacement construction schedule provides for 6 shifts for which the control room ventilation will be operating in the isolrtion mode during the first week of construction for each channel. Operations will coordinate with Construction to 1

place control room ventilation in the isolation mode when required.

After approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in the isolation mode, Operations and Construction will coordinate to return one TGIS channel to operable eikpepibnce n iC6h tFol"jeti od it ii bssed ion s prev 16s Dipe rati ona status. Thei24EhonE rbbsTint'ilsti6E^Will"thsh^b'e YstErhed"to normal"('unii81ated) operation until Construction requires another

. period of isolation.

1 Should Construction be unable to return one TGIS channel to operable status after the control room has been in the isolation mode er if th CREACUS cannct be initiated cr maintained in the 4*letica =cdc cf cperatica due to equipment malfunction, it is permissible asiaicoritibgenc)]to return control room ventilation to normal operat~iori"to' allow ~the control room air quality to return to normal cr to repair :::cciated CREACUS equip =cnt.

Dstf655thes5 periods M " gas Natch"1WillibesproVideditormonitoFTforftbxicMas eventssandfalerticontroliroom! personnel M iithandfheldsradictor tel ephone,2 totimmed i ate 19lpl acel t hsis6n tFolfpoom l i n ttheii sol at fon mode l off op4 rat ioni shoul d l anyipotenti alltski cfga sfeVe'nti!!istobserved!

Thise"contingen 93'availabl# h5ve been fcund acceptable b=d ongss?

actuation ~Will"be' risk = lysi: d = ribcd bclcw and will not c = cd 5? bcur; cver the entirc TCIS instrumentation repl = :ent.

The 54 hcur period is ard for contingency use only.

h cd en

revicu mainten = c histcry, 54 hcur; i

beli = d tc bc : r==:lc len;;th cf ti=c to allcw for rc:tcration of an incperable TCIS ch=cl.

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( un i sol at ed)l model of 40pe rati onsheh i ndi channsllo fsTGIS hi sfiviilibl s i s ?. nots part iofi t helpl anned ? cons t puct i onischedul etssd!sil ls bs/ ssed "

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i nd i vi dual s teacFe~qu i pped s wi t hl ai hand ; hel d1 pad i oM 0nesi nd i vi du al wil Econti n sou sli! moni t6 rtt heIon s i teiammoni~as ten ks fo rischident s T

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i To improve reliability of TGIS operation, preventive maintenance will be performed on the operable channel of TGIS instrumentation prior to the start of TGIS instrumentation replacement.

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5.0 SAFETY ANALYSIS:

The proposed Technical Specification change described above shall be deemed to involve a significant hazards consideration if there is a positive finding in any one of the following areas:

1.

Will operation of the facility in accordance with this proposed change involve a significant increase.in the probability or consequences of any accident previously evaluated?

Response: No The Toxic Gas Isolation System (TGIS) is designed to monitor and mitigate the effects of toxic gas releases on control room habitability. TGIS unavailability is not a precursor to any accident previously evaluated in Chapter 15 of the San Gnofre Updated Final Safety Analysis Report (UFSAR).

A risk :: cssment of the TCIS instrumentatien replacement activity w;; perfor:cd and fcund that the likelibcod of a les: cf centrol rec: habitability bcycad that pcraf tted by the Technical Specifications (TS) will act exceed IE 5 cver the duratica cf thi-TS change.

In addition, a 1c;; cf control rec: habitability dec not necessarily lead to an accident er core d ::ge event.

McwcVer, if a 100; cf control rec:

habitability was conservatively :: umed to lead to a core damage event, this increa:c in risk wculd still not constitute ;

s414f4eant increase in the conscquence; cr probability of any 9

accident previcu ly evaluated since the increa c is les than 3% of the average annual cerc damage risk frc internal events reported in the San Oncfre Individual Plant Ex: ination.

Therefore, operation of the facility in accordance with this proposed change does not involve a significant increase in the probability or consequences of any accident previously evaluated, t

2.

Will operation of the facility in accordance with this proposed change create the possibility of a new or different kind of accident from any previously evaluated?

Response: No This change extends the allowed outage times of the TGIS system.

The change does not affect the design or operation of any other plant systems. An increase in TGIS unavailability is not a precursor to any accident previously evaluated in Chapter 15 of the San Onofre UFSAR.

Therefore, operation of the facility in accordance with this proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

l 3.

Will operation of the facility in accordance with this proposed change involve a significant reduction in a margin of safety?

4 Response: No During replacement of TGIS instrumentation a single channel of TGIS will be maintained operable except during periods when construction activity may result in spurious TGIS alarms.

During these periods the control room will normally be isolated except for brief dontingency? periods when the control room will be open to allow for aip~6xchsnge er to allcw for CREACUS cquip=cnt repair. These pericds, when the control rec: is Open withcut TCIS channel availabic, will act excccd Si hcur; during the entire pcried when this change is in effect. Du ri ngTt he seicon t i ngendys peri od sik)"g a s WatchEwill?be3rosidedit6?monitorlforTpotentialstoxicigassevents and ilal.ertlMontrolj roomL personnelMi all hand ? hel d f rad i s ? orMel ephc6el t osimmed i ately M ace ithe icon t r61Eroomii n i thesi sol a t i onT modeio f" ope'FationishouldianyTpotentia11 toxic @ssiesntibefobseFvedK.4The "ga s!. wa t ch t[wi l l ? cont i nuously%ssTbs; abl elt 6? al e rtipe rs6n i

c on s erv at i vely? i s ol a teit he t control sroomi be foreit oxi c s g as e sources 70fftoxiefgas'e'slandith sireac theic6ntr61proomt'aMiritake SThiidi ni conj uncti on1 wi th ! the M imi ted durat i on : o ff:t helequi pmen tire (plicementK resul t%i nsa yl evel {o f{s a fe thatli st equival.entu toithatt experi en'ced /in s normalkpl a~ntioperation ~ "

i WithithelTGISiavailable.110pbrht'!5ENith"E5htF5T rshiT6ntildt'!5n in"thB"ndfs51~sede"with h single channel cf TCIS cper ble for ii day :nd nc TCIS channel available for up to S4 hour; h:: been analy cd, and rc ult; in an incrc :c in the probability cf a les:

Of ccatrcl rec: habitability which dec: not excccd IE S cver the duration of thi TS changer Therefore, this proposed change does not involve a significant reduction in a margin of safety.

6.0 SAFETY AND SIGNIFICANT HAZARDS DETERNINATION:

Based on the above Safety Analysis, it is concluded that: (1) the proposed change does not constitute a significant hazards consideration as defined by 10 CFR 50.92; and (2) there is reasonable assurance that the health and safety of the public will not be endangered by the proposed change. Moreover, because this action does not involve a significant hazards consideration, it will also not result in a condition which significantly alters the impact of the station on the

. environment as described in the NRC Final Environmental Statement.

7.0 REFERENCES

i 1.

Scuthern California Ediscn San Oncfrc Nuclear Cencrating Statica 1993 Offsite M;;;rd: Update, NSC/PRA Repcrt PRA 2/3 03 008, Occcaber 1993 1

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ATTACHMENT A EXISTING TECHNICAL SPECIFICATIONS UNIT 2

a Ia_th 3.3-3 (Continued)

TABLE NOTATION ACTION 13 With the number of channels OPERABLE less than required by the minimum channels OPERA 8LE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the emergency (except as required by ACTIONS 14,15) mode of operation.

l

. ACTION 14 With the number of channels OPERA 8LE one less than the total number of channels, restore the inoperable channel to OPERA 8LE status within 7 days or within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation.

ACTION 15 With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation.

ACTION 16 With the number of channels OPERA 8LE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.12.

With the number'of channels OPERA 8LE less than required by the ACTION 17 minimum channels OPERABLE requirement, operation may continue provided that the purge valves are maintained closed.

ACTION 17a -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.4.5.1.

(Mode 1, 2, 3, 4 only)

ACTION 17b -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, close each of the contain-ment purge penetrations providing direct accdss from the contain-ment atmosphere to the outside atmosphere.

JAN 111985 SAN ONOFRE-UNIT 2 3/4 3-21.

Amendcent No. 31 r-e,w y

m r

w e

ATTACHMENT B EXISTING TECHNICAL SPECIFICATIONS UNIT 3 4

e d

'i 4

a

Table 3.3-3 (Continued)

TABLE NOTATION With the number of channels OPERABLE 1ess than required by the ACTION 13 minimum channels OPERABLE. requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the emergency (except as required by ACTIONS 14, 15) mode of operation.

ACTION 14 With the number of channels OPERABLE one less than the total number of channels, restore the inoperable channel to OPERABLE status within 7 days or within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation.

ACTION 15 With the number of channels OPERABLE less than required by the minimum channels OPERA 8LE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation.

ACTION 16 With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.12.

ACTION 17 With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, operation may continue provided that the purge valves are maintained closed.

ACTION 17a -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.4.5.1. (MODE 1, 2, 3,4 only)

ACTION 17b -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, close each of the contain-ment purge penetrations providing direct access from the con-tainment atmosphere to the outside atmosphere.

JAN 1 i 1985 SAN ONOFRE-UNIT 3 3/4 3-21 AMENDMENT NO. 20

t ATTACHMENT C PROP 3 SED TECliNICAL SPECIFICATIONS UNIT 2

I

?.

l

\\

Table 3.3-3 (Continued)

TABLE NOTATION ACTION IS -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the emergency (except as required by ACTIONS 14, 15) mode of operation.

ACTION 14 -

With the number of channels OPERABLE one less than the total number of channels, restore the inoperable channel to OPERABLE status within 7 days or within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation.

(SeelNote?{}

ACTION l~5 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup i

j system in the isolation mode of operation.

(SeejNo_teH)

ACTION 16 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.12.

ACTION 17 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, operation may continue provided that the purge valves are maintained closed.

ACTION 17a - With the number of channels OPERABLE less than required by the i

minimum channels OPERABLE requirement, comply with the ACTION i

requirements of Specification 3.4.5.1.

(Mode 1, 2, 3, 4 only)

ACTION l17b-With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, close each of the l

containment purge penetrations providing direct access from the j

containment atmosphere to the outside atmosphere.

NOTEkt w iDuriniconstrudtionifor;DCP :2/3E6933(0_0SMActidns714fand?!51will T

nott be;::;i n l effec t W Compen s atory :! acti on s?for3 theiTGI S!chsnnel s" l

willt:be con. ducted (in?accordanceTwithftheioctoberV18M1995,;

,I Ediionlletterz toi the;U;S. [NucleariRegul atoryiCommissionf

,I i

i 1

I e

SAN l0NOFRE-UNIT 2 3/4 3'21 AMENDMENT NO.

l l

l l'

I

j 2

4 ATTACHMENT D PROPOSED TECHNICAL SPECIFICATIONS UNIT 3 1

~,

Table 3.3-3 (Continued)

TABLE NOTATION ACTION 13 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the emergency (except as required by ACTIONS.14, 15) mode of operation.

ACTION 14 -

With the number of channels OPERABLE one less than the total number of channels, restore the inoperable channel to OPERABLE status within 7 days or within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> initiate and maintain operation of the control room emergency air cleanup system in-the isolation mode of operation.

(pee [Notsy])

ACTION 15 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate and maintain operation of the control room emergency air cleanup system in the isolation mode of operation. JSee]NoteJ1)

ACTION 16 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.9.12.

ACTION 17 -

With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, operation may continue provided that the purge valves are maintained closed.

ACTION 17a - With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, comply with the ACTION requirements of Specification 3.4.5.1.

(MODE 1, 2, 3, 4 only)

ACTION 17b - With the number of channels OPERABLE less than required by the minimum channels OPERABLE requirement, close each of the j

containment purge penetrations providing direct access from the containment atmosphere to the outside atmosphere.

l NOTEilt M f Duri ngIc6nstrUctioliiforf DCPA2/3 ^6933;00SMAct i onU14findiil 5 Twill

'"no t/ be s i ni e f fec tid C6spkns a tory {actichs ? f orit hb ?TG ISIEhannel s ~

" ^ ' ~ ~ ' '

W111 l bs icenduc t ed ii n ?accoidancei wi thj:t he10ctobeQ18h1995)

EdisonjletteritoJthe1U(SGNucleayRegplatory[CommissionF~

1, i

a SAN ON0FRE - UNIT 3 3/4 3-21 AMENDMENT NO.