ML19351E042
| ML19351E042 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 01/25/1965 |
| From: | YANKEE ATOMIC ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML19351E041 | List: |
| References | |
| NUDOCS 8011250512 | |
| Download: ML19351E042 (9) | |
Text
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$$$${ &k $b-2 li
- 'n YANKEE NUCLEAR PalLt STATION OPERATION REPORT UO. h6 l
For the month of DIIEMBER 196h O
8 O
Submitted by YANKEE ATOMIC ELECTRIC C0!LPANY Boston Massachusetts January 25, 1965 8011250
This report covers the operation of the Yankee Atomic Electric Company plant at Howe, thssachusetts for the month of December,19Ch.
Throughout the reporting period the plant operated at or near full output of 185 FWe. Total generation for the month amounted to 13$,901,700 K4ii establishing a new record high for an individual month.
Plant operations were generally normal and routine except for two brief periods of chemistry testing which are described in the Chemistry section of this report.
Spent ion exchange resin disposal and subsequent capsule recla-mation continued throughout most of the reporting period.
Operations have now been suspended to permit acquisition of shipping casks with increased shield thickness, which were found to be required as the radiation levels of individual capsules now lef t in storage exceed the capabilities of the present casks.
No reactor scrams or shutdoins occurred during December.
j Plant Maintenance Following is a summary of major activities carried out by the plant maintenance staff during December.
1.
The heat exchanger for the primary water storage tank was installed.
2.
Repackea and changed rams on Number 1 charging pump.
3 Repaired a broken shaf t on Number 1 gravity drain tank transfer pump.
h.
Replaced a diaphram valve in the water treatment plant.
Replaced a failed gland bolt on the water treatment acid (1
pump.
V 6.
Reworked the distillate accumulator drain valve in the waste disposal building.
7 Made thread chasing tool for cleaning reactor vessel studs.
8.
Repaired a steam regulator in the water treatment area.
9 Changed filters in the auxiliary bay f an room.
10.
Completed modifications to the control rod drive test stand for compressing dash pots.
- 11. Weekly lubrication and inspections were carried out as scheduled.
m.
I i
Chemistry m
During December a series of tests was conducted to add to the data collected previously on crud releases and crud now distributed in the
L main coolant system. The object of the tests was to dete. 'ne the self cleanup rate of the main coolant system without external in tences and to evaluate the present corrosion and crud release rates.
On December 3, following a rod exercise and subsequent increase in the circulating crud level, coolant feed, bleed, and purification were secured.
Crud 1cvels decreased at a nain coolant system half removal rate of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
(Time required for crud levels to decrease by a factor of two).
A s;nilar test was performed on December 9, except that bleed, feed, and purification were lef t in service. The total half removal rate was measured at 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> as compared to a calculated theoretical rate of 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> with 2$ gpm purification flow. The four Four difference was attributed to crud dropout and deposition in the main coolant system as represented by the main coolant system half removal rate measured in the
(,
previous test. This rate was calculated from the result s of the second test V
to be 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />.
A third test was performed in which a circulating crud equilibrium level was established with the bleed, feed, and purification systems operating.
These systems were then secured until a new higher equilibrium level was reached. Calculations based on this data and an assumed constant corrosion rate gave a nain coolant system half removal rate of 19 hours2.199074e-4 days <br />0.00528 hours <br />3.141534e-5 weeks <br />7.2295e-6 months <br /> which was in 8
close agreement with the calculated value of 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> in the December 9 test.
Essentially these tests have pointed out that the main coolant system is itself a crud removal system and actually purifies water by allowing crud to drop out in low velocity areas and pockets.
During the month the average main coolant gross non-gaseous specific getivity was neasured at 6.2 x 10-2 11c/ml.
Of this total, only 1.2 x 10- Jue/ml was due to I-131.
The I-131/I-133 atomic ratio was measured at 0.h$ thus indicating that essentially no fuel defects are 7-(,)
present in Core IV.
This is particularly significant when one considers fuel assembly A-8 which is now cn its third burnup cycle achieving thus far a total burnup of approximately 25,000 lilD/T.
Coolant boron concentration decreased from kh0 ppm at the beginning of the reporting period to 302 ppm at month's end.
A typical nain coolant gas analysis performed December 12,196h indicated :
Xe - 135
$.0 x 10- uc/cc A-hl 3 97 x 10-1s,nc/cc A typical main coolant crud analysis performed on December 1,196h indic ated:
y 5
Cr - 51 1.8 x 10 ;ue/ml 5
.j Mn - $h 1.8x109mc/ml 7.0 x 10. Juc Fe - $9
/ml Co - $d 3.$ x 100 Juc/ml Co - 60 6.7 x 15 mc/ml Hf - 181 Not dete ted In - 116m 1 5 x 10 suc/ml
. Previous Operation Reports have discussed test programs that were established to determine which of the two neutron sou"cos removed from service s
during the past refueling was leaking. Af ter storage in the Spent Fuel Pit for several weeks, the tuo sources were separately encapsulated, pressurized and flushed with domineralized water to remove all traces of pit water activity from the encapsulation can.
Both cources were encapsulated for a ninimum of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and both were sampled at least two times after de-pressur-ization.
Sampels from both capsules contained measurable amounts of 60 day Sb-12h. ilowever, the conclusion that both sources leaked was in sono doubt since it was not known if antimony was plated on the internal can surface and subsequently released into the test water.
In an effort to resolve this question, the test can was filled with demineralized water and put aside for a three day period. At the end of this time the can was sampled. A small concentration of the Ag-110m nuclide was present in the test water; however, following silver separation, no an'.imony was found.
It is, therefore, concluded that both neutron sources are leakers.
( j Reactor Plant Performance A small (0.1%) slowly occurring reactivity gain was reclized during the three day chemistry test mentioned previously.
It is believed that this gain was due to the increase in main coolant pH caused by the buildup of sodium and lithium. On December 18, following termination of the test, the 8
depletion rate returned to noro 1 following the reactivity loss.
entire gain was lost when purification floa was re-established. The core During the first 3200 WD/T average burnup cf the core, which encompasses the period September 2,196h to December 31,196h, the core depletion rate was found to be 0.98% 6 Keff/1000111D/f.
This data is in excellent agreenent with calculated data at the measured flux distribution in the core.
The results of a five ($) wire flux wire irradiation were:
0 $96 mt, 376 ppn C, 527 P Tavg B
5 Group A 0 66 /8 inches F
2.6 g
F 2.2 6U QDNBR 2.3 ilot Channel Outlet 5980F Turbine Plant Perfornance Recent calorimetric data has indicated a slight drop in secondary plant performance. The information obtained thus far is incomplete, however, and a more detailed follow of the problem is underway. It is expected that a more definitive statement will be available for the January,1965, Operation Report.
_h_
Feedwater heater terminal differences measured during the period were:
Ho. 1 12.0 F Ho. 2 13.20F Ho, 3 11.3 F Circulating water inlet temperatures continued to drop during the month resulting in a much lower condenser back pressure and subsequent higher plant electrical output at rated reactor plant conditions of 600 >W.
t Instrumentation and Control Following is a sunnary of majcr activities carried out by the Instrumentation and Control group during December:
1.
Readjusted denineralizer flow meter controls.
v 2.
Repaired seve al survey meters and the P.C.A. check point smear counter.
3 Completed rebuilding of spare UIC and CIC neutron detectors.
h.
Calibrated and installed a new main steam throttle pressure 8
gage.
5 Prepared a check-off procedure for use in interchanging nuclear power range panels while operating at power.
6.
Conrleted preventive maintenance on all the area radiation moultors in the plant.
7.
Completed a check-off list for Vapor Container trip valve (D
testing.
v 8.
Investigated improvements for shutdown cooling temperature control.
9 Adjusted the low pressure surge tank high level dump valve controller.
10.
Repaired the printing cycle circuit in the radiation monitoring recorde:.
Health and Safety During the month of December,196h, h6 drums of radioactive waste containing a total activity of 68.68$ curies were prepared and shipped from the site. This shipnent consisted of 22 drums of routine waste containing a total activity of 38 nc, and 2h drums of special waste (expended ion
~~
exchange resin) ccntaining 68.6h7 curies.
Liquid wastes containing a total activity of 0.0$ me were discharged during December. Gaseous waste containing an estimated 17.6 rc of activity due to radiochemistry sampling were discharged during the same period.
Ion exchange pit leakage during December amounted to 117,8h9 gallons containing a total activity of 0.2h me.
Pumping and disposal of expended ion exchange resins continued during the nonth. Centact levels on tne casks at tino of shipment varied fron 20 to 170 nr/h IIcar the end of the reporting period resin disposal operations were suspended as the chield thickness of the shipping casks proved inadequate for resins fron capsules reading > $0 R/hr contact. New cask designs with increased shield thicknesses have been submitted by the contractor.
Fivesagvagedionexchangecapsulesweredecontaminatedtoless than 1,000 dpm/ft and placed in the drum storage area. Radiation levels ranged from l$ mr/hr to 150 nr/hr contact.
O Equipment used during resin removal operations has been bagged,
,agged, and placed in temporary storage for future rcu Cogtactra ation and contaminatirn levels range from 2 - 30 mr/hr rw 1 dpm/f t Personnel exposures for Yankee plant personnel as neasured by film badge for the month of December,196h were:
Average for all station personnel
- 120 mr 8
ant Operations Maximum individual exposure
- 700 mr Pl Attached is a surmary of plant operation statistics for the month of December, 196h and a plot of daily average plant load for the same period.
Correction O
the or 88 oo"erett "> st>ti " servic "a "et oe"er=tio" rie"res for 1:ovenber should be corrected to read:
Month Year To Date Gross Generation 129,971,h00 1,121,6$h,600 3,827,21h,500 Station Service (Uhile 7,872,253 73,676,192 271,hh8,227 Generation Incl. losses)
Net Generations 122,099,lh7 1,0h7,978,h08 3,$$$,766,273
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3 TANGE ATOMIC ELECTRIC COMPANT - OPERATING
SUMMARY
ELECTRICAL NETH TEAR TO DATE Oross Generation NH 135,901,700 1,257,$$6,300 3,963,11c,200 Sta. Service (While Gen. Incl. Iosses)
NH 8,213,88h 81,890,075 279,662,111 Net Generation NH 127,687,816 1,175,666,22h 3,083,h$h,089 Station Service 6.0h 6.$1 7 0$
Sta. Service (While Not Gen. Incl. Iosses)
NH 0
1,753,000 20,608,651 Ave. Gen. For Month (7hh IIR3)
W 182,663 Ave. Gen.
D= ming (7hh liRS)
W 182,663 PIANT PERFORMUICE Net Plant Efficiency 28.87 27.99 Net Plant Esat Rate Btu /NH D.,821 12,193 Ibe. Steam /het KWH 1h.03 1h.39 Circulating Water Inlet Temp.
leavi-m F
$1 MLni = =
OF 36 Plant Operating Factor 99.06 79.71 69.13
[
NUCLEAR 70 NTH CORE IV_
TO DATE Times Critical o
19 3hh Hours Critical BRS 7hh 2829.09 30,629.58 Tisses Scransmed o
g up huivalent Reactor Hours @ 600 N t HRS 737 03 2660.29 21,$h8.99 Average Burnup of Core ND/mtU Control Rod Position at Month Ibd Equilibrium at $95 !!,lt
$27 F Tav;
- RMION
!Oiml CORQ Oroup A Rods out-inches 872 Group B 90 Enla 992.60 12,103.67 Group C 90 IIIDDLZ 1100.h8 88$d.9h Group D 90 OUTEt 675.36 2h33.11 E-6 815.82 25,0$h.10 Boron 302 ppm
]
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YANKEE ATOMIC ELECTRIC COMPANY DAILY AVERAGE LOAD for December, 19614 4
4 150 -
I E
b e
100 -
~
S 8
=
W 50 -
U 2
o 0
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i ii'iie i
=
5 10 15 20 25 30 DAYS
CORE I7 REDION IOCATIONS OUTER REDION MIDDLE O
aioton rv INN R 8
i RID::0N E-6 l
O u6 Assembly ;;;,11-8 k
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