ML19332B261

Monthly Operating Rept for Aug 1980

ML19332B261
Person / Time
Site:	Fort Saint Vrain
Issue date:	09/02/1980
From:	Gahm J PUBLIC SERVICE CO. OF COLORADO
To:
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ML19332B259	List: ML19332B258 ML19332B261
References
NUDOCS 8009260386
Download: ML19332B261 (10)

Text

emb PUBLIC SERVICE C0'!PRIY OF COLORADO FORT ST. VRAIN !.'UCLEAR GENERATING STATION

!!ONTHLY OPERATIONS REPORT NO. SO AUGUST, 1980 I:

8 0 0 9 2 6 0 32rb

This report contains the highlights of the Fort St. Vrain, Unit No. I activities, operated under the provisions of the Nuclear Reuglatory Commission Operating License, OPR-34.

This report is for the month of August, 1980.

1:0 NARRATIVE

SUMMARY

OF OPERATING EXPERIENCE AND MAJOR SAFETY RELATED MAINTENANCE 1.1 Summary At the beginning of this report period, the plant was in the following operating condition:

Reactor power at 50*;,

turbine generator load at 135 MW, feedwater flow through the emergency feedwater header (due to heater #5 leakage),

and average core region outlet temperature of 1188 degrees fahrenheit.

The plant continued to operate between 50*4 and 55% reactor power until 1115 hours0.0129 days <br />0.31 hours <br />0.00184 weeks <br />4.242575e-4 months <br /> on August 4, 1980, at which time a scram occurred.

The scram was caused by feedwater control system problems.

The plant protective system responded to the feedwater flow problem by inducing a four circulator steam turbine trip,

scram, Loop 1

shutdown, and immediate turbine trip.

Recovery from scram was initiated immediately, and the reactor returned to criticality at 0200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> on August 5,

1980.

Investigation of the initiating cause is still uncerway at this time.

Reactor power was increased to 27's on August 7, 1980, and the turbine generator placed on line.

Power escalation was hampered by lack of available feedwater flow (caused by leaking isolation valves around the "B"

boiler feedpump),

loss of one circulating water pump (caused by a bad bearing), and high air temperatures in the Reactor Building (caused by insufficient cooling capacity of the available service water).

Power levels of 50 to 55% were attained by August 16, 1980.

On August 16, 1980, additional problems developed within the secondary coolant system, particularaly the boiler feedpump controls, necessitating a reduction in load to 60 MWe.

During the period of reduced load for investigation of the feed:: ump control problem, a hycraulic oil leak develoced on PV-2244 (Loco 2 circuhter steam turoine bypass valve),

causing heavy smoke and a small fire.

The leak necessitated isolation of tne Loop 2 hydraulic oil

system, and reactor power reduction to 2*. followed by a manual scram.

Necessary repairs were mace to the hycraulic system of PV-2244, the feecpump isolation valve, and the oil spill associated with PV-2244 was cleaned uo prior to the reactor being brought critical on August 18, 1980.

Reactor power was escalated as fast as primary and seconcary

,~

coolant concitions allowec and was at a level of 5 7*.

on August 22, 1980. A severe bycass flew concition develoced

. on HV-31119 ("B" boiler feedpump emergency header isolation valve), and the load was reduced frem 160 MWe to 140 Mwe on August 27, 1980, as a result of this leak.

On August 25,12 inoperable snubbers were discovered while conducting the scheduled Technical Specification Surveillance, and the plant entered into the grace period of LCO 4.2.10.

On August 29, the main turbine generator suffered a loss of the electro-hydraulic control panel : 24V supply.

The unit remained operable on the PMG; but at 1335 hours0.0155 days <br />0.371 hours <br />0.00221 weeks <br />5.079675e-4 months <br /> wnile attempting to determine the cause of the loss : 24V power, the plant electricians inadvertently caused a turbine runback. The resultant transient caused a circulator in each loop to be tripped by plant protective system action.

The turbine generator was manually tripped at this time.

Since the 12 inoperable snubbers discovered on August 25, 1980, could not be repaired within the Technical Specification allotted time, the " planned shutdown" planned for September 1, 1980, was initiated.

1.2 Ocerations At the beginning of this report period, the plant was operating at a reactor power level of approximately 50% and 135 MWe.

The secondary coolant flow path was established through the emergency feecwater header.

This flow path was necessitated by the fact that heater #5 was inoperable due to tube leaks.

The average core region outlet temperature was being maintained below 1200 degrees fahrenheit as the primary coolant oxidants were greater than 10 ppm.

At approximatley 1630 hours0.0189 days <br />0.453 hours <br />0.0027 weeks <br />6.20215e-4 months <br /> on August 1, 1980, reactor power was increased to 52%, resulting in an average core outlet temperature of 1220 degrees fahrenheit,as primary coolant oxidants had been reduced to a total of 8.8 ppm.

Operation continued with essentially the same conditions as cescribed above until 1115 hours0.0129 days <br />0.31 hours <br />0.00184 weeks <br />4.242575e-4 months <br /> on August 4,

1980, when a plant protective system action resulted in a reactor scram, four circulater steam turbine trip, and Loop 1 shutcown.

The cause of the above upset was an unstable feedwater control system whose root problem seemed to be centered around the feedump speed control system.

Further investigation of this problem is still underway.

Precarations for a reactor restart were made almost immediately, anc criticality was attained at 0200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> on August 5, 1980. On August 6, reactor power was increased to 27%, and on August 7, 19SO, tne main turoine

(

i olaced in service.

Reactor pcwer level was increased to generator was l

47%, but a load cecrease was necessary to hold the reactor j

ouilcing temoeratures witnin acceotaole limits, as the neat loac exceecec the cacacility of the cnilled water system.

This proclem was for the most part, cue to tne uncersi:ing

I of the service water piping supplying the reactor building chillers.

An additional condition that developed, which also limited plant operation, was the presence of a bad bearing on "A"

circulating water pump.

This condition coupled with the hot weather, caused high back pressure in the condenser, thus limiting turbine generator load.

Plant operation continued as dictated by conditions described above until August 12, 1980, when a turbine runback occurred.

The cause to date has been attributed to action from an improperly set vacuum switch.

This switch action is believed to have caused an upset in the feedpump control portion of the secondary coolant control system.

Recovery from the turbine runback was made and plant conditions remained stable until August 16, 1980.

On August 16, 1980, a hydraulic oil leak developed on PV-2244 (circulator steam turbine bypass valve) which necessitated isolating Loop 2 hydraulic oil system and Loop 2 group 2 secondary coolant loop.

Reactor power was also reduced to 2%, and the reactor scrammed as prescribed by the Emergency Procecures.

During the shutdown for repair of the hydraulic oil leak and oil cleanup, the leaking "B" boiler feedpump normal feecwater header isolation valve was

repaired, along with repair of "A" boiler feedpump speed control. After completion of the above mentioned work, preparations were made to bring the reactor critical, and criticality was achieved on August 18, 1980, at 1245 hours0.0144 days <br />0.346 hours <br />0.00206 weeks <br />4.737225e-4 months <br />.

Reactor power was increased to 28%,

and the turbine generator synchroni:ed at 1135 hours0.0131 days <br />0.315 hours <br />0.00188 weeks <br />4.318675e-4 months <br /> on August 20.

As soon as feedwater chemistry was within specification, the power level was increased to 57% and turbine generator leaded to 160 MWe.

On August 25, 1980, during the piping snubber surveillance, it was discovered that 12 snubcers were inoperable.

Per Technical Specification requirements, these problems must ce corrected within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or an orderly plant shutdown is required within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> after expiration of the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

During this grace period on August 29,

1980, a proolem developed with the electro-hycraulic control system for the main turbine generator in that it suffered a loss of : 24V power.

The main turbine generator continued to operate on the permanent magnet generation.

At 1335 h0urs wnile attempting to determine the cause of the loss of ; 2dV power, the plant electricians inadvertently caused a turbine runback.

The resultant transient caused a circulator in eacn loop to be tripped by plant protective system action.

The turbine gennerator was manually trioced at tnis time.

Since the 12 inocerable snuboers discoverec on August 25, 1980, could not be recaired witnin :ne allottec time, tne l

" plant snutcewn" clanned for Septemoer 1,

1980, was initiated.

1 l

4 The plant will remain shutdewn down for required surveillance testing and selected maintenance until the latter part of September.

2.0 SINGLE RELEASES OF RADI0 ACTIVITY OR RADIATION EXPOSURE IN EXCESS OF 10% OF THE ALLOWA8LE ANNUAL VALUE None 3.0 INDICATION OF FAILED FUEL RESULTING FRCM IRRADIATED FUEL EXAMINATICNS None 4.0 MONTHLY OPERATING DATA REPORT Attached l

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cetu m e SATA uro u coCrn so. 50-267 DA3 800902 Cenrtr:ra sr J. W. Gahm Tz:.zrucn (303) 785-2253 cataA::xc su res soTzs

1. tait se.es Fort St. Vrain 2.

Repor: ins rectod: 800801 through 800831 3.

Licensed Thermal Fever Oste): 842 4

Nameplate Rating (Cross We): 342 5.

Design Electrical Racing Ote lSie):

330 6.

Maximum Oependable Capsei:7 (Cross We): 342 7.

Maximum Oependable Capacity Cret We): 330 S.

If Changes occur is Capacity Ratissa (:tene Number 3 Through 7) Since Last Report, Give lessons:

None 7.

Power Level To '4hich Restricted. If Any (Net We): 231 u.

Kasser.s for aastrie: ions, :t Any: Nuclear Regulatorv Com11ssion restriction 70" rendfaa resolution of temperature fluctuations.

I This Month Year to Oate Cunea14tive

. Hours is zapor

iss Period 744 5,855 10.272

. seer of Ecurs Rase:or vu Critical 619.4 4,343.1 6.975.9 u.

eae:ar ?4 serve shutdown sours 0.0 0.0 0.0 la. sours cenerator ca.t:s.

517.7 2,974.9 3.957.1

u. : nit neeerm shu:down sours 0.0 0.0 0.0

6. Oroes hermal Isergy cenerated (s a) 217,522 1,350.116 M S.071

17. Grees nee rt:a1 Inergy Oecerated (51) 66,793 429.129 569.925

15. Nec nee:rical Iserzy cenerate.' cs.1) 60,272 393.379 516.963 3.

si: s<rvice rac:or 69.6" 50.8" 38.Si

. :nt: Avat:4bt:1:7 rae:or 69.6" 50.8" 38.Si

. :si: capaci:, rac:ar (esias MDc 3e:)

24.5" 20.4%

15.3*

. :si: casaci:7 rae:ar c:siss ::a : ret) 24.5" 20.4" 15.31 n. :si: rar:e4 :ucas aate 24.5:

30.1*

44.0"

!a. shutdeves sesaduled aver :res: 6 M: stas (Type. :ste, and :uration of rach): Through Sentenber 30.

1980, to complete recuired surveillance testin2.

3.

If !*.aut :own at Isd of ter: : Period. L:. sated ate :f !cartup: October 1. 1980

$. !stes s Test statu (?- :: :s C:= tr:ia; Operation):

T:recas t Acnieved l

IN!!!.C. 01:"!CM.:7.

N/A N/A l

i N

.'*.AL I:.I:3:::!!

N/A N/A

?!!sy,gs3nianacA AnjgyLyta nfinigjy3nes 50-267

,, n r.,

UNIT NA%E Fort St. Vrain DATE 800902 ctwo a.Erun ni J. W. Cahm mErt*T HONMI August, 1980 Tturm>NE (303) 785-2253 HEnuno or SafUTTING Denne SYSTEN cleSONENT mD.

DATE TYRE tstmATION WF.ASON kEAtruit 1.Ett i (2)l>E QHat cAUSE ANil CHNRt'CTIVE ACTION Tu FREVENT DECURRf30CE __

110-15 !!001104 F

65.2 11 3

N/A N/A N/A Reactor scram and turbine trip occurred due to loss of all four circulators.

110-16 110 0111 6 F

102.7 A

2 50-267/80-45/03-L AD PIPEXX

'rurbine tripped and reactor manually scranuned as a conservative measure due to rupture of a hydraulic oil supply 1ine.

110 - 17 1100t!29 S

58.4 11 1

N/A N/A N/A Following a turbine runback as a result of personnel working on the EllC system, the turbine was manually tripped and the reactor shut down. This began the scheduled shutdown for surveillance testing.

SiltillARY: Schedialed shutilown fo. marveillance testing throughout the month of Septeniher, g

f I

.A

AVERAGE DATLY UNIT POWER LEVEL Docket No. 50-267 Unit Fort St. Vrain Date 800902 J. W. Cahm Completed By Telephone (303) 785-2253 Month August, 1980 DAY AVERAGE DAILY POWER LEVEL DAY AVERAGE DAILY POWER LEVEL

(.We-Ne c)

(>Sie-Ne t) 1 128 17

_0_

2 133 18 3 132 19

_o_

4 57 20 25 5

-b 21 65 6 22 106 7

37 23 107 8

24 146 9

107 25 146 10 105 26 143 11 103 27 146 12 123 23 137 13 129 29 66 14 137 30 15 152 31 16 9

• Generator on line but no net generation.

l REFUELING INFORMATION 1.

Name of Facility, Fort St. Vrain, Unit No. 1 2.

Scheduled date for next refueling shutdown.

June 1, 1981 3.

Scheduled date for restart followina refueling.

September 1,1981 4.

Will refueling or resumption of operation thereafter require a technical specification change i

or other license amendment?

No If answer is yes, what, in general, will these be?

If answer is no, has the reload The Plant Operations Review Committee will fuel design and core configura-review any questions associated with the tion been reviewed by your Plant icore reload.

Safety Review Committee to deter-sine whether any unreviewed safety questions are associated with the core reload (Reference i

10CFR Section 50.59)?

l I

1 i

If no such review has taken 1

olace, when is it scheduled?

January 1, 1981 l 5.

Scheduled date(s) for submitting t

e proposed licensing action and l

suceorting information.

\\

6.

Important licensing considera-tions associated with refueling, e.g., new or different fuel de-sign or supplier, unreviewed design or performance analysis methods, significant changes in fuel design, new operating pro-cadures.

7.

The number of fuel asse=blies a) 1482 ETGR fuel elenents (a) in the core and (b) in

}

the scent fuel storage = col.

b) 8 spent E R :.uel ele =ents l

S.

The present licensed spent fuel Capacity is limited in sice to about pool storage capacity and the third of core (approximately 500 E!GR ele-one-

[

si:e of any increase in licensed nents).

No change is planned.

i storage capacity that has been t

l requested or is planned, in I

nu=ber of fuel assenblies.

i

RETJELING INFORMATION (CONT!NTIED) 9.

The projected date of the 1986 under the Three Party Agreement (Con-last refueling that can be tract AT (04-3)-633) between DOE, Public discharged to the spent fuel Service Company of Colorado (PSCo), and pool assuming the present General Atomic Co=pany.*

licensed cacacitv.

• The 1986 date is based on the understanding that spent fuel discharged during the term of the Three Party Agreement will be shipped to the Idaho National Engineering Laboratory for storage by DOE at the Idaho Che=ical Processing Plant (ICPP).

The storage capacity has evidently been si:ed to accomodate fuel which is expected to be discharged during the eight year period covered by the Three Party Agreement.

t

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