ML19351E006
| ML19351E006 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 01/21/1966 |
| From: | YANKEE ATOMIC ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML19351E003 | List: |
| References | |
| NUDOCS 8011250398 | |
| Download: ML19351E006 (9) | |
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%Wb' YANKEE NUCLF.AR POL STATION OPERATION REPORT NO. 60 For the month of c}
DECEMBER 1966
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Submitted by YANKEE ATOMIC ELECTRIC COMPANY Boston Massachusetts January 21, 1966 Cr 31 801.i150
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4 This report covere the operation of the Yankee Atomic Electric Company plant at Rowe, Massachusetts for the month of December 1965 The plant was base loaded at full licensed power level, equivalent to about 18$ M4e gross, during this reporting period.
Operation was normal and routine throughout the period except for two occasions, one on the lhth and the other on the 25th when a low pitched hum and vibration started to emanate from the vicinity of the high pressure turbine. On the lhth, the hum and vibration slowly increased and quickly died away without any corrective action being taken. The overall time of this incident was estimated to be two minutes. On the l
2$th, the incident lasted less than two minutes and terminated af ter a hand adjustment was made to the number four servo control.
The manu-facturer has been notified of these incidents.
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The yard area crane, which handles the 70 ton spent fuel cask, was modified to increase its margin of safety during spent fuel handling.
The modifications were designed and supplied by the original manufacturer of the crane. The installations were made by the plant staff under the observation of the manufacturer. Test lif ts subsequent to the modifications were not acceptable to Yankee and consultants, ard spent fuel shipments s
were suspended until satisfactory modifications can be made to the crane.
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,i As a result of the normal fluid interchange during Core IV-V refueling, boron concentrations in the spent fuel pit increased to about 200 ppm. In view of the dissimilar metals in use in the pit it was decided to improve water resistivity. The boron concentration is now being reduced by dilution. The pit level is lowered and about 35,000 gallons of demineralized water is added. This operation will be repeated until the water in the pit reaches acceptable purity and resistivity.
,,(j Durir.g the year 1965, a record for reactor control system reliability was set when there were no unscheduled reactor scrams during the entire year. The plant also set a new record by generating for 1$6 consecutive days. The reactor was suberitical on only three occasions during 1965, the first in February for temporary switchyard repairs, the second in August for refueling, and, the third in November for scheduled physics tests and turbine repair.
Plant Maintenance Following is a list of the major items performed by the plant staff:
1.
Uprating modifications started on yard area crane.
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2.
Emergency lighting was installed over the Diesel genera tor
~s and mair h80 y switchgear.
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. 3 I check valve was installed in the waste disposal recycle line downstream of WD-V-737 h.
The low pressure surge tank makeup pump was repacked.
$. An automatic draf t damper was fabricated and installed in the waste incinerator inlet.
6.
Power and control for the fire system pressure maintenance pump was relocated from MCC6 bus 2 to MCC6 bus 1 to facilitate operator action on total loss of AC power.
Chemistry The main coolant oxygen concentration remained less than
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$0 ppb, the limit of detection,throughout the period.
The main coolant gross activity (less tritium) was in the range of 8.0 x 10-2 pc/ml and the crud level varied from 0.10 to 0.17 ppm.
The main coolant tritium concentration is still increasing and was 3.8h pc/ml at period end. Secondary plant tritium level also was on the increase and had reached a concentration of h x 10-3 pc/ml. At this
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point secondary plant makeup was increased and excess water was diluted and discharged. At period end, the secondary plant tritium level had decreased to 3.1 x 10-3 ic/ml, with the secondary plant makeup set at f
about 9000 gal / day.
Oross activity in the steam generator blowdown varies between background and 1 x 10-8 pc/ml.
If the tritium in the secondary plant was due to primary-to-secondary steam gegerator leakage, one would expect the gross concentration to be in the 10- pc/ml range. This apparent g) inconsistency is being explored further.
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The iodine-131 specific activity was 1 3 x 10-3 pc/ml and the I-131/I-133 atomic atio measured at 0 76 in the primary plant.
A typical main coolant gas analysis was as follows:
A - h1 7.2 x 10- pc/cc of gas Xe - 133 3.~r x 10- pc/cc of gas Xe - 135 7 7 x 10- pc/cc of gas A typical main coolant crud analysis was as follows:
77x10fdpm/m3 Mn - 5h Cr - 51 9.7 x 10 dpm/mg Hf - 181 1.h x 105 dpm/mg
,7 3 Fe - $9 1.0 x 10 dpm/mg l
's Co - $8 2.0 x 106 dpm/cg Co - 60 9.h x 105 dpm/mg
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. 4 An analysis made of pressurizer drain water was as follows:
0 60 ppb s <cific activity 2.2 x 10- pc/ml pb $.2 boron 910 ppm conductivity 2.8 y mhos Reactor Plant Performance Main coolant flow data was obtained and analyzed in an attempt to measure any changes in core flow as a result of the installation of necondary core supports and thermal shield straps in the flow area outside tne core. Core V flow rates were measured at h2.h x 106 lbs/hr, while measurements in 1961 were h2 x 106 lbs/hr. It can be concluded that no measureable flow changes have occurred as a result of the above instal-lations.
o Analysis of core reactivity data resulted in a Core V measured burnup rate of approximately 0 9% 6 K per 1000 mfd /MPU.
The results of a h wire flux wire irradiation were (for stain-less clad fuel) as follows:
0 Reactor conditions: $98 Mit, $27 F T avg.
- q = 2.5 F
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6 H, 2,0 q"DNER = 3 3 T outlet of hot channel - $93 F Turbine Plant Performance The results of feedwater heater terminal difference measurements h
at 18h.5 Mie, condenser back pressure of 153" Hg and T avg of $26.8oF are as follows:
- 1 92F
- 2 13 5 F
- 3 11.1 F Instrumentation and Control The following is a list of the major items performed by the plant staff during December:
1.
Repaired the VC air particulate monitor vacuum pump.
2.
Repaired the Health Physics smear counter timer.
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3 Relocated the bleed line gamma detector.
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Checked the calibration of the main coolant narrow range
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temperature channels.
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-h-5 Replaced the pressurizer system temperature selector switch.
6.
Repaired the blue pen amplifier on the main control board nuclear recorder.
7 Performed preventive maintenance on the area radiation monitors.
8.
Repaired several portable survey meters.
9 Calibrated several selected secondary plant instruments used in the determination of plant efficiency.
Health and Safety O
During the month of December 1965, the following solid radio-active wastes were shipped off site for disposal:
1.
169 drums containing a total of 1158 me.
2.
Two shipments in a special cask, total activity 2.hh curies.
Each shipnent consisted of 1h drums of waste, whose radiation levels were too high for normal shipment
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200 mr/hr contact).
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Liquid waste disposal releases totaling 216,070 gallons containing a gross beta-gamma activity of 1.38 me and 12h.$ curies of tritium, were discharged during December. Gaseous waste from chemistry sampling contained a total activity of 13.7 me.
In addition to the above releases, 262,500 gallons of water con *,aining 2.9 curies of tritium were released from the secondary plant.
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i A calibration check of the plant radiation monitoring system was performed during the period.
The evaporator distillate " polishing" filters were changed. The total activity contained in the nine filters was estimated to be $8 r.c, predominantly Ag llom.
A special survey was made of the waste disposal plant evaporator with the following result:
location contact level (mr/hr) inlet lines 100-150 outlet lines 100-300 pumps 100-200 f
i evaporator, side, 68 from top 600 evaporator, top 30-100 s
evaporator, bottom 200
f Radiation levels were measured in the spent fuel pit before and after the water level was lowered as part of the boron dilution process.
The radiation levels were 2 to $ mr/hr generally with the water at normal level. With the water level down 8 feet the radiation levels were 7 to 11 mr/hr. The normal water depth is approximately 31 feet over the spent fuel.
Yankee plant personnel radiation exposures as measured by film badge for the month of December 1%$ were:
Average exposure 108 mrem Maximum individual 'xposure h50 mrem Plant Operations (q
Attached is a summary of plant operation statistics for the
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month of December 1965.
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YANKEE ATOMIC ELECTRIC COMPANY -- OPHIATING SUIMRY DIEIGER 1965 EIETRICAL M0lmi YEAR TO DATE Gross Generation KWH 137,h09,100 1,027,72h,700(1) h,990,8h0,900 Sta. Service (While Gen. Incl. Losses)
KWH 8,03h,360 66,750,38$
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Net Generation KWH 129,37h,7h0 960,97h,315(1) h,6hh,h28,h06(1)
Station Service 5 85 6.h9 6.9h Sta. Service (While Not Gen. Incl. Iosses)
KWH Ave. Gen. For Month (7hh HRS)
KW 18h,690 Ave. Gen. Running (7hh las)
KW 18h,690 PIANT PmFORMANCE Net Plant Efficiency 29.27 28.27 28.hh Net Plant Heat Rate Btu /KWH 11,660 12,072 12,000 D. Steam / Net KWH 13.95 13.98 Circulating Water Inlet Temp.
0F 36 Mnimnm 7
Minimum F
ho Plant Operating Factor 99 02 6h.69 68.20 Reactor Plant Availability 100.00 75 7h 80 52 NUCLEAR ENTH CORE V TO DATE Times Critical 0
lh 371 Hours Critical HRS 7hh 1223.72 37,18h.68 Times Scrammed 0
0 hp Equivalent Reactor Hours @ 600 IWt HRS Average Burnup of Core IMD/MI'u*
Control Rod Position at Month Ehd Equilibrium at 18h.8 Mie
- REION ENTH TOTAL BURNUP 0
Group A Rods out-inches 90 Group B 870 A (INN m) 870.0$
16,807.08 Group C 87 B (MIDDLE) 1005.03 8,2hl.62 0
Group D 870 C (0UTm) 757.96 1,109.6L ZIRCAIOY TEST ASSaiBLIES 1317.21 1,937. %
Boron v 816 ppm (1) Totals corrected to include trans. losses of 316,$h2 h'd omitted from Nov. 1965 totals.
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YANKEE ATOMIC ELECTRIC COMPANY DAILY AVERAGE LOAD for DEE.BZf 1965 1
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CORE V REGION II) CATIONS REDII)N C r
REDI )N B O
D REDII)N A h
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D - ZIRCAIOY TEST ASSEMBLIES U
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