ML17174A287

Responds to NRC Requests for Info Re Loss of Offsite Power Events at Facility.Forwards Answers to Questions Re 651112 & 780122 Events,Ler 78-005/03L-0,780122 Deviation Rept & List of 345 Kv & 138 Kv Line Failures During 1974-1979

ML17174A287
Person / Time
Site:	Dresden
Issue date:	12/19/1979
From:	Janecek R COMMONWEALTH EDISON CO.
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
NUDOCS 7912270345
Download: ML17174A287 (21)

Text

e Commonwe. Edison One First National Plaza. Chicago, Illinois Address Reply to: Post Office Box 767 Chicago, Illinois 60690 December 19, 1979 Mr. Darrell G. Eisenhut, Acting Director Division of Operating Reactors U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

Dresden Station Units 1, 2, and 3 Response to Request for Information Concerning Loss of Offsite Power Events NRC Docket Nos. 50-10/237/249 References (a):

T. A. Ippolito letter to C. Reed dated September 18, 1979 (b)

D. L. Ziemann letter to C. Reed dated September 25, 1979 (c)

D. L. Ziemann letter to D. L. Peoples dated December 4, 1979

Dear Mr. Eisenhut:

This letter is in response to the requests for information concerning loss of offsite power events at Dresden Station Units 1, 2, and 3 which were transmitted by References (a), (b), and (c).

We have researched the events of 1/22/78 and 3/4/78 mentioned in Reference (b).

We have concluded that the event of 3/4/78 was not a loss of power event, and have included an event which occurred on 11/12/65. provides our responses to the questions concerning the events of 11/12/65 and 1/22/78 and includes additional reports written shortly after the events occurred.

The unavailability of offsite power due to 138KV transmission line outages is included in Enclosure 2.

References (a) and (c) have been reviewed, and the following response is provided.

1.

The event that occur~ed at Dresden Unit 3 on August 21, 1975 was not a loss of off-si~e power.

As indicated in Deviation Report #50-249/75-35, the event was a circuit breaker trip test.

The main functfon of breaker 152-3403 is to isolate bus 34 in the event of a loss of off-site power.

A 0 1 $"

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Commonwealth Edison.

NRC Docket Nos. 50-10/237/249 Mr~ Darrell G. Eisenhut 2 -

December 19, 1979

2.

Dr~sden Unit 2/3 has never lost all of its off-site power.

3.

Auxiliary power has been available at all times to Units 2 and 3.

4.

a)

Unit 3 ring bus is connected to three 345 KV lines (L. 1223, L. 8014, L. 1222) and connected to the Unit 2 345 KV ring through breaker 4-8, which is normally open.

b)

Unit 2 ring bus is connected to three 345 KV lines (L. 0302, L. 1220, L. 1221) and connected to the 138 KV bus through transformer 81.

Trans-former 81, which tied the 345 KV yard with the 138 KV yard, was installed in October, 1976.

c)

Unit 1 138 KV bus is connected to six 138 KV lines (L. 0904, L. 1205, L. 1210, L. 0903, L. 1206, L. 1207).

d)

Dresden Unit 2/3 has never lost more than one of its 345 KV lines at the same time.

It is unlikely that a loss of one line will cause a decrease of voltage or decay of frequency.

5.

The information concerning the failure of 345 KV lines between 1970 -

1973 is obtainable, but securing this information requires extensive time and effort.

Information concerning the decrease of voltage is available for the period between 1973 -

1979, but it, too, requires extensive time and effort.

Data concerning the decrease of frequency is unavailable. contains a list of 345 KV and 138 KV lines

.that failed, the causes of failure, and the periods of time when unavailable between 1974 and 1979.

If you have any additional questions, or if you require the additional information mentioned in Item 5 above to complete your review, please contact this office.

One (1) signed original and thirty-n~ne (39) copies of this transmitt~l are provided for your use.

Attachments Very truly yours, v;1.~-~

~.A.!(C-Robert F. J' necek Nuclear Licensing Administrator Boiling Water Reactors

ENCLOSURE I RESPONSE TO QUESTIONS FOR LOSS OF OFFSITE POWER EVENTS DRESDEN UNIT 1

.e ANSWERS TO QUESTIONS FOR EVENT ON 11/12/65 TOTAL LOSS OF OFFSITE POWER

1.

The exact time auxiliary power was made available is not clear, but the reactor was off line from 1452 on 11/12/65 to 1632 on 11/13/65 for a total of 25 hours2.893519e-4 days <br />0.00694 hours <br />4.133598e-5 weeks <br />9.5125e-6 months <br />, 40 minutes.

2.

Turbine trip was almost inunediate.

Loss of offsite power occurred at the same time the main transformer output was lost from tornadic activity.

Turbine overspeed trip occurred a short time after the main output lines were downed.

3.

Offsite. power was restored the next day.

4.

Voltage readings are unavailable.

5.

Tite turbine tripped on overspeed due to loss of main load.

Other transient details are unavailable.

6.

Date of event was 11/12/65.

ANSWERS TO QUESTIONS FOR EVENT ON 1/22/78 PARTIAL LOSS OF OFFSITE Pa.lER

1.

Normally~ seven circuits are available for offsite power delivered through two transformers.

2.

Auto transfer capability of bus 11 to bus 13 was blocked due to a lock out signal affecting the bus tie breaker.

3.

The lock out signal was due to an improper neutral over current relay setting on the backup diesel generator circuit.

The lock out signal was only sent to the bus tie breaker, so no other cir-cuits were affected. *

4.

No voltage fluctuations occurred.

5.

No frequency fluctuations occurred.

6.

The circuit for auxiliary power from TR 13 was unavailable from 0155 to 0910 for a total of 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />, 15 minutes.

7.

Date was 1/22/78.

. :.. r-11-65 Ope1*:itil)n l1::is conducted on Lo.:id Schedule ~:ur..bcr lS, which w.:is placed.

into effect Otl November l, This schadula continues the lo:id foltowin3 of system r:?quir.?t:t.?nts, with the elit.iin2tior. of tho aftarnoon load drcp (Fizure 3),

Thero was one out3ge dur'ln:; tlte month C&.IU!ied by storm dtt:~ge to all electrical tran3mission lines, The 1033 of the lines c.:iu~:?d the turbin~ to trip on over~peed and the reactor scr~r.m~d. Further detnils ara pre3cnt~d in this section '1nd in the Nuclonr Section of t~i~ report, Outnl.?.e

!,urbi!le

.... 'l.'he turbine wes tripped on over~pced result ins ~rom load shell and e1113rgcncy shutclow!\\ procedures were followed.

The exhaust hood temperatures had be~n running at 95° F. for the turbine end and 100° F. on tbc gc:1erntor end prior to the outage.

Ir.::::ccibtely aft~r the trip, both tcr.:pcrntures dropped to 65° F, This wt1s due to th:? loss of steam fl.ow to th:? condan!!ar w\\1ile coolin~ water was still b*:!in::; s:.>ppli*ld by the power zcnarat.~d :!~ th'! t11r!>ina* ~;.:s dropping in sp~cd.

Th~ hooc tc~pero tur~

then becan to increase at an nver.:ig~ rate of 73° F. per hour until it ret1chacl 223° i-*.

(3~3 p:;ig.) at 5: 00 p.r.i. 4t which tfruc the :outh\\*1.::;t r;,ipturc dii:c en the L. l'. turbine rupt11r-:!d.

• Ih1rin3 startup on Novc."Tlhcr 13, 19~5 it was di3coverecl th:lt the st;ca::t seal dum;> vnlve to "A1' cxtrnction \\las stack cpcn 01110:*1:!.ng stc.:tm t.J.:?ntcr the L~ P. turbine. It is beliclvad th:it this valve:? W.'.ls stuck opun at the ticc ol trip, allo-;..rin:; heatin& cf the turbine e:<haust hood.

The ruptur<! disc ~.ls rcplac~d by 3:20*a.m. on November 13, 1965.

The ei:i.?rgcncy condenser w<ls pl:iced in OFcration ~:.ito:.::it!.cally d;.1P. to tho loss of the snfcty syste~ volt::i:~.

D~ring th~ half hou= of opcr~:ion, 71, 700 lbs. of waccr w;is ev:lp.orat~d and 37.1 ?r.:t v:i~ ri?j-:!cted to the condenser.

Thi3 co!np.;:res favorably uith rc~ults ol.lt:iin~d 'in 1-l::.rch of thL1 year whc.n tte north half hanril.?d 20.6 ~r.*it.

Oper.:ticn wa3 sati.3factory thr.oughout :he operatin3 pericd.

Conr:!enser Tube Laaks Thro~ co~denscr.tubc leaks w~re plugi~d during th~ outJze.

All thre~

were l~cntcd in the upp~r v~st h~lf of the v~st condcn~ar. There Jre now ~

total of three tu~cs plusg~d in t~e e~3t half of th~ cond~nscr and 13 tubes plugzcd i.n the west hal! of th!? co1\\de~.:;cr.

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TAllLE l REACTOR AND 'IU?.Bl?:Z GENEMTOR SERVICE 1-I O~ercti!°*G Conditions Lo~d'Sch~dul~ Uo. 16 in effect Hov. l.

Load Scbe<lulc ~o. 18. f,

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• SC:o ~cr&o ~cr.~tion Survey Sheet.

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• ~ N-11*65 Su1m1aq Dresden operated essentially on Load Schedule Humbar 18 throughout the month of November e:<cept for the forced outage eApcricnced on ?:ovember 12, 1965 due to its loss of load and system tie as ca~scd by torn~do da~aze to the 1.38 1'.'V transmission syste:u about three ciles northwl?st of the station.

Incore flux wires were irradi3ted on November 9, 1965 and incore mon1.tors adjusted on ?lovember 12, 1965. Monthly control rod power worth checks were conducted at both half and full power during the month.

The rods varied in worth from 3 to 9 ?-~-le as exhibited in Fi&ure 1 *

. Thoria rods were renovcd fro~ 83 of the 107 Type II stainless clad asseablics during the month.

The thoria rods and U02 fragr.:ents found during the rod rc~oval activity will be de$ignatcd as batch :s. All partial asserablies containing UOz rods will be desisnated as botch 04 for purposes of chemical processing.

The trend of core c3pabil+/-ty as exhibited in Fizu~e 2 is indicat~d by the trend in prwry feedwaur floi-1 rate req:.iired to o:aintain 200 J:':;e with constant rod pattern during the.interval.

The prinsry steam gencr~tion capability and flow rates raquirad appear to now be dropping at a fairly constant rate.

Tran9icnt Pcrfo~ronc~ of Reactor ~nd Associated Egul~~ent DurinR To~nado Caused Shutdot.n T'ne unit tripped out at 200 MJe when all the transnission lines (138 and 34. 5 KV) *.:are darr.aged by the tornado on ?lover;iber 12, 1965.

The sequence o! events and transients experienc.?d ~:C?re essentially the sace as the full po~cr senerator trip test coaducted on July 3, 1965.

The only significant difference was the te::iporary loss of auxili.lry pot*ar, a short tir.ie after the reactor scra::-.:ned, which cut in the encr~ency stear: concenser and produced other minor phenorr.~non. The reactor and its assoc!at~d equipment functioned properly and a safe sh'.ltdo~.m conditio~ was easily achieved.

The transients eh-perienced are depicted in Figure 3.

The sequence of events are s'.1:.r..arized in Table 1, 'Jith the peal: values listed in Tn!:>le 2.

The control rod patterns before and after the unit cutage are shown in Figure

4.

0 0 Reference A

~

~

SCP.AM OPEMTION Str.'1!1ARY SHEET Time - Dnte 2:50 p.m.

11/12/65 Reason Lout all 133 KV ond 34.S KV lines between 2:40 p.m.

ond 2:50 p.m.

Loas of lood couscd turbine ovcrspecd.

Renctor scrammed on high flux by collopsins of the voids.

Avcrace rise wns 891. to 13 T4.

Reactor Condition Reactor critical 617 MHt, 50 rods and 10 notches withdrown.

• ,~

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~-* The pressure incrca$e ca-:.iscd by tho closing of. the prinary co~trol valves opened the bypass valves and proouc~d ~he.following:

1.

An incrense in the differential pressure '"hicb increased the recirculation flow.

This moved the void boundry up the flow ch~nnel *.

2.

A collapse of voids (2 kinds) due to the increase in reactor pressure.

a.

Change in saturation pressure convcrtins so~~ steam to water.

b.

Increase in moderator density.

Each of abovo phenoi'l:mon decreased the neutron leoikage and increased the moderation.

This increased the reactivity "'1hich res-:.ilted in increasing reactor flux.

It is believed that the secor.d phenomenon gradually replaces

• the first with a time delay of som~thing less than a second.

The neutron flux incrca:led on the average from 89 percent to a peak of 137 (Figure 3-~). All six of the pou~r rans~ instrur..ents s.:iw this incrca=e in flux.

The heat flu:~ als? iocre;iscd by about 117..

Incore ins.tni!Ilents, though calibrated to i.!easura h.::at fluY., actually oeasuras neutron flux.

Since tha fuel has a time constant tho h~at fl*J~ ac the clcdd!ni; sur foce is a function of both neutrcn flo:.1x and tima during transients.

Ily nn~lo~ co::nc>uter studies of simU~r flu:< responses it was deterr.1ined that tbe rise in h~at flu~< was a sfT'.all frnction of the rise in n~utron flux.

Such a St:.!lll incre.ase in heat flux is possible, since th~ fluh spike 'Uas only one or two seconc:!s in du:-ation anc the fuel has a ti.Ille const<:nt o! ab":>ut 8 seconds.

The ra~ctor scr::unr::~d whca tha nc:.itron flux pnssed 1207. on the out-of-core ins'tru:r.~nts and other 3crani signals ware lciter initi.lt~d by (a) loss of oil pressure, (b) loss of auxiliary AC po~~r, (c) the clo3ura of pr!r.:~ry steam valves a~d sphere isol~ticn v<llves, (d) lo~ cond~nser vacuum.

The actual scram ten:iinnted the flu:°' incre.ase and shut the reactor down to a* level of about

67. from which it further deC.:!/'~d.

Th~ flux spike lasted only 3bout one or two seconds.

All !ods _were ins~rted e:<cept C-9 and J-2 *..1hich were valv.?d out of service.

Reactor was placed in shutco:-m with C-9 at 8.ind J-2 at 12.

The bypass v~lves closed bec~use the pressure dropped belo~ the normal operating level of 1000 psi.

The tir.:e fro::i when the pressure started increasing until it dropped be_low the 'operating level,,;as about 3 seconds.

An additior.al spi~e of 30 psi. w~s experienced as the press~re wns falling in the vicinity cf 920 psi.

This short transient was caused by the closing of th~ bypass valves (Figure 3-F).

Genera to:- transfonr.er circuit brca!~er tripped at 2: 52 p.m. by the motorina protecti~n circ~it after a delay oE 90 seconds free the tir.le the steao supply to the turbine ~as int~rrupted.

o:-U-6S Coat.)

- 14 The follo~in:; events oc<:*Jrred:

Lost all au~iliary po~er at 2:53 p.~.

Scram sicnal from loss of AC povu.

All four recirculation pumps trippc!d d*Jc to loss of auxiliary power or drum level.

Emerseney cond~ns~r cut in &nd sy~tem isolation valves tripped due to loss of au~ilia=y powar (Figure 3-I).

valves:

Scram sigr.al due to clos~re of prielry :ite3:i valves and sphere isolation All recoreers stepped for l

~ 2 ~inutes.

E1:1ergency dieGel generator cut in at 2:52 p.m.

Scram sig~l received due to 10*.1 condenser vacuum ('Fig;ire 4-B).

Aft9r shutdcwn the reactor vessel temperature decaye~. very slot~ly until at approxL~3tely $:40 p.a. "When cooling w:iter \\7as introduced into the reactor by the c~ar~:ncy pri~~ry feed pu~p. This resulted in a rapid decr~ase in the. tem~eratu:c of the vessel bottc:i until 3t 9: 50 p.m. this ta:;perar:ura reaci1ctJ a lo'A' of 200° F.

Tho mid-sect i.on and nanzc tempera tu re decay rates were not affected by this cooling w.:iter and the bottoo i:o mid-point te:.iperature differential appl."o9ched lc0° F.

The no:ninal.licit for this differential is 150° F.

Tlle nC!!linal li::1its for tho te:r.?l!rat-.ire di!forcmtials were not even ap?roachcd durin; th~ period of :rnnsfonts i.r:-:;:2dic:to?ly following tb scr:a1:1.

Infon:atio:i prov1.ced *by Ge:\\eral Zlec:ric Co:?:p~ny, San Jo:ie, Californfa by ph"'ne on Dece~ber 3, 1955 indi~~ted that exccedin~ the differ~nti<ll tc~p~rature limit by 30° F. would net d~~ase the vessel or shorten its lifetir.1e.

The reactcr was brought critical on a *127 sec. period.:lt l~: 32 p.t'l.

November 13, 1965 with 37 rods 7 notche:J ~ithdrawn. At 9: 15 p.rn. the reactor was producing steam at rated prcssurl!.

Figure 4 shous control rod pattarn5 *in use ~uring the period.

T:ype II ru~l Asse~blie~ Thoi:J!I Rod ~e~

Nine of the forty-nine fuel reds in eJch of th~ Type II fuel assemblie3 contain thorfa, Fiaure 5.

It "3ClS r.ecessary that each sec of nine rods be removed fro~ the fuel asse=~lies before they are shipped for reprocessing.

These rods were placed in spe~ial cont3iners a!ter removal froQ the asse~~lies. Tne containers used for unda~aged thoria rods consist of J4 stainless steel t*.!bes rco:.mtcd in a frnTJawot!<.

Th~ final size of this tY?a of con~ainer is the sace as that of a not"::.al facl assElmbly.

'!'he:Je are designated TS-1 thro~zh TS-23, Figure 6.

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FIGUR~

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• Turbine Hlh (A)

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l.500 Tiroe

1

l. Load on

~J Generator 100(

50 1')0 Valvo Fo3i tion

(';~) Open lOO.P;i 111:.1 ry 50.Sec.

I (B) 500 Time (C)

J.)00 I '"°'

.l!).)v Psic 10.5 Reactor Pressure (1016) 9.5

• l,4JO

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uua Heter 100 5c

'Scram 100 D~~ss Vzilves

,i: ()pen

. 14JO (D) 1 00

. 15JO Tillle (E)

Transfer 0£ Power Source 15)0 Time (F)

Tiir.c

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Pri. Stm. Flow*

x io-0 (lb.,.hr) 2.(

1.

(G)

.1430

. l.500 Time 1 JO

_ Renctot Inlet Wat r..Le111p.

OF' 500 400

)50 Time Emergency Condenser Temper;'\\tures (I)

).,.u 600 S temn Inlet t:..

400 Water Stcrago 300 11.:-)0 15UCJ Ti:::c I.-....

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Cont.)

- 27 TABL~ l SEQmmc=: O? E\\~HTS SU?-1*!:\\RY Event All lines out of service.

Turbine start!ns to overspeed.

Prir.i3ry and secondary control valve closure.

Bypass V3lv~s opened.

Pressurg increase.

Prlli:.:lry steam flow increased.

Pressure dif farential increase.

Rc:ictor rec i::cul:l tio.n flow incrcescd ~oo~nta~ily.

Void decrease and ~odcrator density increase.

• Neutron flux incrc3sing.

Reactor scrall:m~d.

Pre~sure decr~nsed.

Bypass valv?s closed.

_Cnuse and D~scriptio~

Due to loss of. electrical load.

By action of the spcad &ovcrnor (acceleration relay).

Due to the closure of the primary control valv~s and tl1e cction of the pressure regulator.

A sli:;ht tll.1~ delay bctu~cu the closin8 of th~ primary ccntrol valve and the op~nins of the bypass valves produced a prcss~rc transient with a peak of 1016 psi.

Opening of the b:'Pass valve allo*1~d the prirocry ste3:n flow to spi!te to 1117. of its initwl valu~.

Du~ to the physical system and 'th~ inc-cear.e in prcssura.

Due to an incrca~e in the pres3ure differential.

Due to incrc~sed reactor recirculati~n floY and incr~ased reactor prcssura.

Due to void dccrc~se and ~odcrator density increase.

The flux increased on the avcr~g~

froci &9 to 13 71..

By the out-of-cor*! monitors when thc flux went past 1207..

This stopped the flux ris~

and shut th~ reactor do':."tl.

Due to the cp~ning of the bypass and the scras:u:tin~ of the reactor.

Because the press~re dro?ped bclo~ tha n~rt!!al op~rating level.

i l

'I 1

)

(lt-11-65 Cont.)

Event Pressure decrease.

Turbine tripped.

• Generator tTansforr:i~r circuit brenk~r tripped.

Lost all auxilfary,POW<lr.

Scrai1 signnl.

All four recirculation PWl'}>S tripped. TABLe l (Cont.)

Cause l\\nd Dcsc?'i~

• Due to opening of th9 bypass valve and scra::oin3 of the reactor.

A s~all spike in the pressure *while it was decreas!.ng was due to tba bypass valves closin~.

By the overspc~d governor.

By th.c mot:orir1g protection cii.-cuit after a delay of 90 seconds from tha time the steam supply to t~c turbine was interrupted.

Because ttv:? gen:!rator transfom~r circuit brc~kcr tripped.

P'roci loss of AC po~*r~r.

Emerzency stca~ condenser cut in Duo to loss of auxiliary ro~cr.

and system isol~tlon valv~s tripp~d.

Scram si~nal.

Due to closure of primary stcac valves and sphere isolation valves.

All rccordars ~topped for one to tuo.minutes *.

Emargenc7 dics~l generator cut in service.

Sc-ram s !gna 1.

Loss of AC rowar, or.ly DC available.

Manually.

Due to 101J condenser vncuuc.

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t j I e Q

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. (N-11-65 Cont.)

MWt T'..irb ine Speed (R?M)

PrL-::3ry Valve Position By;.-nss Valv~ Position Reactor Prcssur~

Neutron Flux (uu~)

Prir.ary Stcao Flow Eracrcency Cor.d. Te~p.

Steam lnl~t (0 P.)

Water Stor.:izc Exhaust Ro"d Temp. ( 0 P.).

Cond. Vacuura (In. H8)

Pumps in S~rvice BOR TABt.t: 2

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TAA?ISir-:llT DATA (1. 1n1.~l ln1.t id

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1002 89 1.61

'132 86 95 28.3 4

2.5 0

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6SS (111) 1950 (109)

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1016 (101. 3) 137 (l5l*)

1. 76 (111) 515 (390) 216 (251) 223.

(235) 28.9 (102) 4 2.?

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J (6,C ro1 O hours, the bus 13 to bus 11 bus tie Jzre~ker 1107 was gbseryed to be in a loc;kedl

.EJ Louc :ondition, There was no alarm annunciation for this condition because the breaker IJ [did ~ot trip since it was in the open position at the time lock out occurred, This l:J 1 loc:k out signal blocked the auto transfer capability of bus 11, The safety significancf?

iJ 11s =!.~i:lal oecause the reactor was only critical from 0325 to 0709 hours0.00821 days <br />0.197 hours <br />0.00117 weeks <br />2.697745e-4 months <br />.

This is not D fa re;>etitive occurrence.

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ATT'~CHMENT NPRD-'

PRIME COMP.

REVISION NO.

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.CTION OHP\\.AHT MiTtoOC M0URS ~

. SIJIMITTtO

'<<)RM:.1.18.

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. CAUSE Ol:SCRIPTION ANO CORRECTIVE ACTIONS @

47

)) I 'n:.a lock out was caused by a neutral time over current vhich resulted from a phase IJ I U:~alance in the vye-vye connection between TR13 and the temoorary PG dyring test1pi

)) I a: 0155 hours0.00179 days <br />0.0431 hours <br />2.562831e-4 weeks <br />5.89775e-5 months <br />.

Immediate action was to reset the lock out.

Long term action is to 2J I ic:reasc the neutral overcurrent setpoint and verify the 1107 lockout status after DG I] I op~:-ation.

OTMERSTATVS NA LOCATION OF RELEASE @

NA BO 80

DEVIATION REPORT DVR NO.

STA UNIT YW NO.

D l

• 9

. L OF OEYIATION J *

~cku? diesel and TR!J. Unavailable During Operation pirfM AFFECTED PLANT CONDITIONS OCCURRED 1-22-78 DATE ocnn TIME TESTING D

CXJ Refuel PWRMWT 0

LOAD MWE 0

YES NO PflON Of EVENT

.~!!el shift relief panel check, NSO noted Bus 11 Feed Brkr 1107 "trip" light up(rio..!n..tlunciatlor.

_.,.1,h indicated the brltr in the "lock out" condition.

tn this-mode, the brkr -would not have' clqsed and TR13 and the !mergencv Backup Diesel were unavailable.

DESCRIPTION Of CAUSE Further investigation revealed backup diesel vas operated at 0155 to wam diesel oil after re-ce;lving low tamp alarm.

A second operation at 1224_ hrs revealed that each time diesel was tied

. OTHER APPLICABLE INFORMATION (OVER)

EQUIPMENT DYES Dl NO.

WR NO.

FAJWRE C!INO NA 559

?ART 2 I OPERATING ENGINEERS COMME"NTS JMR for v. Rockovski llESPONSIBLE SUPEQVISOR 1-22-78 DATE Improper setpoint of neutral O.C. Relay.

Procedures have been issued to verify O.C. lock-out reset 3ft,.t diesel operation.

SNEp reviewing pt'oper setpoint of relay to prevent its trb vhil i

i e operat ng en~ ne.

SAFETY*

TYPE OF CEVIATION EVE~T OF POTENTIAL TECH SPEC NON* REPORTABLE ANNUAL RELATED REPORTABLE OCCURRENCE PUBLIC INTEREST VIOLATION OCCURRENCE REPORTING WR ISSUED D 14 DAY D IOCFR2f

[!} 30 DA' NOTIFICATION D

i,...... ~.,. Am"""'

123 REPORTABLE CCCURRENCE ACTION ITEM NO.

NUMBER 78-S-03L-O NA Z4*HOUR NRC NOTIFICATION DTPH RA DrQ.t REGIQN l 11 CATE TIME RA REGION Ill 6 COL CATE TIME RESPONSIBLE Cat.!PANY OFFICER JNFOR~ED OF IOCFR2 I N

R R RT C

REVIEW ANO COMPLETED ACCEPT A.NCE BY ST A Tl ON REV I Ei'i AS RECUIREC DATE r

RESOLUTION APPROVED ANO AUTHORIZED FOR DISTRIBUTION

• • • 1111 10*11 r*o.. 11-sa*t>

YES*0 YES 0 o*

D NO O*

NO [)

PROMPT ON*SITE NOTIFICATION B1 Stephenson {Phone}

1-21-78 0910 TITLE DATE TIME NA TITLE CATE TIME PROMPT OFF-SITE NOTIFICATION F. Palmer 1-24-78 3:30 Tl TLE CATE TIME

. J. Gilliom 1-24-78 3:30 Tl TLE DATE Tli'Y4E DATE t l~IE

. l-2J-78.

DATE

DESCRIPTIO~ OF CAUSE {continued) into Bus 13. brkr would trip on neutral overcurrent and could be immediately

• reset after aecuring brkr to normal *

. ~--..

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• -._.ENCLOSURE... 2 DRESDEN STATION 345 KV AND 138 KV LINES FAILURES 1974 TiiROUGH 1979 DATE

• TIME LINE OFF ON OFF ON REASON TR. 81 6-25-78 6-26-78 1239 1835 Cause undetermined TR. 81 10...;21-77 10-21-77 0045 0624 B.T. 6-7 B & C.B. failed TR. 81 1-20-77 1-21-79 1651 1239 B.T. 6-7 C.B. L.B.B. Oper.

L. 1205 7-19-79 7-19-79 0118 0118 Cause undetermined L. 1205 9-30-77 '

9-30-77 2222 2222 Lightning L. 1205 1:-24-77 1-24-77 0046 0046 Contamination (dust on the insulators)

L. 1205 12-18-76 12-18-76 1529 1533 Arrester failed at J371 L. 1205 12-17-76 12-18-76 2337 0040 Contamination (dust on the insulators)

L. 1205 12-17-76 12-17-76 2204 2246 Contamination (dust on the insulators)

L. 1205 5-5-76 5-5-76 1426 1426 Relay malfunction L, 1205 4-23-76 4-23-76 1815 1815 Lightning L. 1205 9-1-74 9-1-74 1003 1003 TR. diff. at TSS 77 L. 1205 8-19-74 8-19-74 1455 1455 Relay malfunction L. 1205 8-2-74 8-2-74 2013 2013 Lightning L. 1206 3-29-79 3-29-79 0015 0015 Lightning L. 1206 1-24-77 1-24-77 0043 0043 Contamination (dust on the insulators)

L. 1206 12-17-76 12-17-76 2204 2204 Contamination (dust on the insulators)

L. 1206 11-20-76 11-20-76 2344 2344 Cause undetermined L. 1206 6-4-76 6-4-76 1140 1140 Static sagged into & wire L *. 1206 8-11-75 8-11-75 1255 1255 Crane contact L. 1206 5-20-75 5-20-75 1748 1748 Lightning and wind L. 1207 7-3-79 7-3-79 2300 2351 Lightning L. 1207 4-6-79 4-6-79 0604 0604 Truck hit pole L. 1207 6-25-78 6-25-78 1521 1521 Lightning L. 1207 10-10-77 10-10-77 2029 2029 Short, broken insulators L. 1207 9-1-77 9-1-77 0250" 0250 Lightning L. 1207 7-3-77 7-3-77 1630 1630 Building on fire under line L. 1207 6-30-77 6-30-77 1516 1516 Lightning L. 1207 8-9-76 8-9-76 1450 1450 Cause undetermined L. 1207 10-24-75 10-24-75 2028 2028 Lightning L. 1207 7-13-75 7-13-75 0357 1307 Sudden press. relay plug shorted L. 1207 4-27-75 4-27-75 0746 0824 Lightning L. 1207 12-1-74 12:-1-74 0713 0716 Wet snow and wind L. 1207 12-1-74 12-1-74 0709 0709 Wet snow and wind L. 1207 12-1-74 '

12-1-74 07Q6_

0706 Wet snow and wind L. 1207 12-1-74 12-1-74 0702 0702 Wet snow and wind L. 1207 12-1-74 12-1-74 0659 0659 Wet snow and wind L. 1207 5-21-7.4 5-21-74 1740 1740 Static wire down L. 1207 3-6-74 3-6-74 2152 2152 Lightning L. 1207 3-4-74 3-4-74 0721 0721 Lightning L. 1210 3-29-79 3-29-79 2305 2315 When els. 1090 was closed L. 1210 7-20-76 7-20-76 1804 1804 Lightning L. 1210 1-26:-76 1-26-76 0540 0540 Current cutout sw. left open L. 1210 1-26-76 1-26-76 0454 0532 Current cutout sw. left open L. 1210 3-27-75 3-27~75 1943 2207 Winds and ice L. 1210 3-27-75 3-27-75 1352 1421 Winds and ice L. 1210 1-17-75 1-17-75 0917 0917 Pulling L. 2310 over L. 1220 1-18-79 1-18-79 1249 1251 Contamination (dust on t.he insulators)

L. 1220 7-13-76 7-13-76 1202 1202 Cause undetermined L. 1220 1-10-75 1-10-75 2015 2015 Lightning

~:....

e

' c :.I**

• .(.-, **------*- -

DATE TIME LINE OFF ON OFF ON REASON L. 1221 2-20-79 2-20-79 0749 0749 Relay malfunction L. 1221 6-30-78 6-30-78 0627 0627 Lightning.

L. 1221 4-2-78 4-3-78 1315 1132 Cause undetermined L. 1221 12-21-77 12-21-77 0524 0605 LBB operation, testing* circuit breaker L. 1221 12-21-77 12-21-77 0006 0023 Cause undetermined T.

1221 10-20-77 10-20-77 0045 0648 Bus Tie 6-7 B & circuit breaker failed at 12 L. 1221 1-20-76 1-20-76:

1651 2329 Bus Tie 6-7 circuit breaker LBB operation L. 1222 1-18-79 1-18-79 1358 1358 Melting snow and contamination L. 1222 2-8-78 2-8-78 1127 1127 Cause undetermined

• L. 1222 2-8-78 2-8-78 1121 1121 Cause undetermined L. 1222 2-3-78 2-3-78 1325 1325 Cause undetermined L. 1222 2-4-76 2-4-76 1306 1306 Cause undetermined L* 1222 8-30-75 8-30-75 1710 1710 Cause undetermined L. 1222 8-22-75 8-22-75 2331 2331 Cause undetermined L. 1222 8-11-75 8-11-75 1638 1638 Cause undetermined L. 1222 2-21-75 2-21-75 0606 0606 Cause undetermined L. 1223 6-25-78 6-25-78 1235 1235 Lightning L. 1223 8-22-75 8-22-75 2331 2331 Cause undetermined L. 1223 8-1-75 8-1-75 1)239 0239 Cause undetermined L. 1223 7-2-74 7-3-74 0907 0102 Static wire downed L. 0302 4-5-79 4-6-79

. 1803 1423 Cause undetermined L. 0302 12-20-77 12-20-77 0241 0241

'Wet snow L. 0302 12-20-77 12-20-77 0256 0256

'Wet snow L. 0302 12-20-77 12-20-77 0304 0304

'Wet snow L. 0302 10-25-77 10-25-77 0314 0314 Wire down Station 3 L. 0302 5-21".'77 5-21-77 2011 2019 Lightning and high winds L. 0302 1-28-77 1-28-77 1036 1036 Cause undetermined L. 0302 6-20-75 6-20-75 1707 1747 Lightning L. 0302 4-7-74 4-7-74 1430 1752 Bus duct cable fault L. 8014 11-26-78 11-27-78 1847 1414 Cause undetermined L. 8014 7-31-78 7-31-78 0037 0037 Cause undetermined L. 8014 12-20-77 12-20-77 0355 1344

'Wet snow L. 8014 1-1-76 1-1-76 0641 0641 Cause undetermined L. 8014 5-20-75 5-28-75 1557 2141 Tornado L. 8014 3-28-75 3-31-75 1944 0523 Static wire down L. 8014 3-27-75 3-27-75 1911 1911 High winds and ice L. 8014 6-6-74 6-6-74 1112 1112 Lightning L. 0903 10-15-79 10-15-79 2256 2256 Lightning L. 0903 8-18-79 8-18-79 0115 0115 Lightning-L. 0903 8-5-79 8-5-79 2022 2022 Lightning L. 0903 3-29~7.9 3-30-79 2251 0006 Static wire down L. 0903 6-22-77 6-22-77 0920 0924 Testing relays L. 0903 5"-24-77

. 5-24-77 1136 1208 LBB relay operation on L. 0913 circuit breaker at Station 9 while attempting to put Unit 7 on line L. 0903 4-6-74 4-6-74 1604 1621 Contractor dropped 765 KV static wire L. 0903 3-18-74 3-18-74 0720 0720 Contamination (dust on the insulators)

L. 0903 3-18-74 3-18-74 0707 0707 Contamination (dust on the insulators)

L. 0903 3-18-74 3-18-74 0704 0704 Contamination (dust on the insulators)

L. 0903 3-18-74

. 3-18-74 0656 0656 Contamination (dust on the insulators)

.i'.'.. tl...... ""'

~*'

LINE L. 0904 L. 0904 L. 0904 L. 0904 L. 0904 T..... 0904 DATE OFF ON 3-28-78 3-28-78 6-11-77 6-11-77 1-13-77 1-13-77 3-18-74 3-18-74 3-18-74 3-18-74 3~18~74 3,..18-74

• TIME OFF ON

• REASON 1444 1444 Cause undetermined 0219 0231 Lightning 0813 1035 Static wire due to pole fire 0720 0720 Contamination (dust on the insulators) 0704 0704 Contamination (dust on the insulators) 0656 0656 Contamination {dust on the insulators)