ML20008E724
| ML20008E724 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 02/27/1981 |
| From: | YANKEE ATOMIC ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20008E723 | List: |
| References | |
| NUDOCS 8103090512 | |
| Download: ML20008E724 (11) | |
Text
O YANKEE ATOMIC ELEGRIC COMPANY YANKEE ATOMIC ELEGRIC NUCLEAR STATION ANNUAL REPORT 1980 Prepared By Yankee Atomic Electric Company Technical Assistant to the Plant Superintendent's Department Star Route Rowe, Massachusetts 01367
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1980 A\\MJAL REPORT Table of Centents TITLE PAGE 1
Title Page 2
Table of Contents - -------------------------------------------
3 Introduction Changes, Test and Experiments:
4 A.
Engineering Design Changes ---------------------------
6 B.
Plant Design Changes --------------------------------_
9 C.
Plant Alterations ------------------- ----------------
D.
Tests -----------------------------------------------
10 E.
Experiments -----------------------------------------
11 Safety and Relief Yahe Failures and Challenges -------------- 11 i
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i INTRODUCTION j
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The Yankee Atomic Electric Nuclear Power Station is a Pressurized Water 4
Reactor (PWR) of 175 MW electrical, maximum dependable capacity (MDC).
The nuclear steam supply system is a Westinghouse 4 loop reactor. -The architect / engineer and constructor for this project was Stone & Webster I
The condenser cooling is once through using Engineering Corporation, Boston.
the Deerfield River as a cooling medium. The plant is operated in accordance l
with license DPR-3, issued July 19, 1960, pursuant to Docket Number 50-29.
The date of initial reactor criticality was August 19, 1960 and commercial r
operation began July 1, 1961.
is submitted in accordance with Technical This annual report tests Those portions of this report concerning changes, Specification 6.9.2.
l and experiments are submitted in accordance with 10 CFR 50.59(b).
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Changes, Tests and Experiments j
A.
Engineering Design Changes 1.
The following is a list of those fully approved Engineering Design Changes that were implemented during the year 1980.
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a.
EDC 79-30 Durin this report period a Primary Coolant Saturation i
i-Monitor was installed to provide continuous on-line j
indication of core cooling conditions. The equipment has been designated as " control grade". Khere it inter-t i
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faces with a safety Class ' System a Safety Class isolation transmitter was used. Therefore, the change posed no unreviewed safety question.
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b.
EDC 79-37 l
i During this report period Acoustic Accelerometers were 1
installed on the Pressuri::er Safety and Relief Valve Dis-charge Piping to give the operators indication of an open j
valve. The change does not pose an unreviewed safety i
question since it meets all LOCA, HELB, and Seismic quali-i fication and gives the operators instrumentation to assess l
plant conditions.
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EDC 79-44 l
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During this report period selected containment Isolation Valves which were detemined to be non essential with re-i j
I spect to safety features or cooling capability,were modified to close on SIAS actuation. This change modified that i
method by which specific containment Isolation Valves can j
i be tripped and analysis was performed to verify that no
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adverse results would occur by closing the valves on an in-1 l
advertent SIAS signal, therefore the change did not pose an unreviewed safety question.
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EDC 79-47 i
j During this report period Ultrasonic Flowmeters were attached to the emergency boiler feed lines to provide flow indication to the steam generators when the emergency boiler feed pump l
j is operating. This change poses no unreviewed safety question since the piping was not penetrated and the operator's ability i
to assess plant conditions is enhanced.
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EDC 79-48 During this report period a redundant level indicator with alam
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was installed for TK-1, Demineralized Water Tank. This change i
poses no unreviewed safety question in that reliability of the plant has been increased.
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EDC 79-52 l
During this report period a cementitious fire proofing material was applied to the structural steel in the three diesel generator rooms. The change posed no unreviewed safety question in that the operation of the plant was not changed and fire protection for the building structure was improved.
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EDC 79-55 During this report the containment Isolation System was modified to eliminate the potential for an inadvertent i
reopening of all CIS valves by installing individual switches j
to open each valve. The change poses no unreviewed safety question in that it reduces the potential for inadvertently opening the containment isolation valves.
h.
EDC 80-8 During this report period the High Pressure Safety Injection Pumps minimum flow orifice size was increased to improve pump operation at shutof f head conditions. The change did not pose an unreviewed safety qu :stion in that the increased flow still met licensing analysis and the ability of the pumps to operate under adverse conditions was increased.
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EDC 80-10 During this report the coutainment isolation system was modified to replace manual reset switches with electric reset switches of a similar type and mount them in the Control Room to allow the operators to allow them to reset any or all lockout relays from a single point.
This change poses no unreviewed safety question in that the ability of the lockout relays to perform their safety function remains the same.
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EDC 80-18 During this report period selected containment Isolation Valves were modified to allow them to be reset and remotely opened while the containment actuation signal is still present.
This change allows the operators to open selected isolation valves to assist them to bring the plant to a safe shutdown condition and therefore poses no unreviewed safety question.
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EDC 80-22 During this report period the charging pump controls were i
changed to prevent the charging pumps from returning to l
their normal mode when SIAS was reset. The change does not pose an unreviewed safety question since it is designed to
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maintain equipment in its safety function positibn until re-q moved by operation action.
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EDC 80-23 ll During this report period the nitrogen pilot. timers for the i
Safety Injection Accumulator actuation was changed so that l
j it would be " sealed in" and would not be reset without direct operator action. The change was to reduce the potential for i
inadvertent termination of safety injection and therefore -
poses no unreviewe' -nklen.
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EDC 80-26 t
I During this report period supports were installed on the steam generators to increase their ability to withstand a Seismic event.
l This change poses no unreviewed safety question since they in-crease plant safety and do not alter, plant operation.
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EDC Sd-42 i
During this report period supports were added to the batteries to increase their ability to withstand a Seisnde event. This
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change did not alter the function of the batteries and therefore did not pose an unreviewed safety question.
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i B.
Plant Design Changes I
1.
The following is a list of those fully approved Plant Design Changes 1
4 that were implemented during the year 1980.
PDC 76-1 During this report period isolation valves were installed in a.
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the stem leakoff system to allow the isolation of individual valves should packing leakage become excessive. This change poses no unreviewed safety question since the change does not adversely affect the system operation and insures that valve stem
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Icakoffs will be able to be isolated.
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PDC 76-37 During this report period the Primary Vent Stack abnitoring System was modified to allow cross connection of the air dryers and 1
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location of the vacuum pumps outside the instrumentation cabinet. The change increased equipment reliability and therefore posed no unreviewed safety question.
c.
PDC 78-19 During this report period the Boiler Feed Pump Recirc. Controls and Feedwater Flow Transmitters were replaced due to the age and decreasing reliability of the original equipment. There was no unreviewed safety question in that the system operation was not changed and plant reliability and safety was enhanced.
d.
PDC 78-20 During this report period a level indicating alam was added to the Fuel Oil Tank (TK-49). The change does not pose an unreviewed safety question since the function of the fuel oil system was not altered and equipment and personnel ra?ety was enhanced.
e.
PDC 79-2 During this report period a spray shield and oil curb were in-stalled in the Safety Injection building to protect equipment from a potential ha:ard of spraying oil, and a coat drainage system was installed to drain the oil which would be contained within the curb. This change does not constitute an unreviewed safety question in that plant operation will remain the same and equipment safety will be improved.
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PDC 79-6 During ths report period a 0-30 inches water detector was added to the charging pump flow detection instrumentation. The detector was installed in parallel to and using the same sensing lines as the existing flow indication. The change does not constitute an unreviewed safety question in that the reliability was increased and functioning of the system enhanced.
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PDC 79-S During this report period a new signal cabic was installed between the Safety Injection Panel and the level transmitter for the safety l
injection tank. The change was to eliminate the spurious alams l
caused by " noise" from other cables. There was no unreviewed safety question since the change improved the system reliabiltiy.
h.
PDC 79-9 During this report period a new instrument air compressor was installed. The change involved piping modifications which allowed the new compressor to supply air to plant instrumenta-tion and service air for other applications. The compressor addition added increased air capacity and redundancy; the original compressors function as backup for the new compressor.
Based on the above summary the change does not pose an unreview-ed safety question.
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PDC 79-10 During this report period a test connection and valve were added upstream of VD-TV-202 to facilitate Type "C" testing. The change did not pose an unreviewed safety question in that the system function was not altered and Type "C" testing made possible which enhanced plant safety.
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PDC 79-12 During this report period Satety Valve Discharge Header Purge Tubing was extended into the Valve Room to reduce personnel exposure when connecting the temporary nitrogen regulator for purging the header. The change was to reduce personnel exposure; the operation of the system remained the same and therefore poses no unreviewed safety question.
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PDC S0-1 During this report period local isolation valves and test valves were added to the Steam Generator NR Level Trip System Level Transmitters to improve the method of calibrating the instruments.
The change did not constitute an unreviewed safety question in that the operation of the system will not be changed.
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PDC 80-5 During this report period Test and Isolation Valves were installed on each Charging Pump Lube Oil Pressure Switch and Pressure Gauge to allow calibration and maintenance of the instrumentation in place. The change does not pose an unreviewed safety question in that the change does not alter the function of the system.
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PDC 80-7 During this report period individual rtinimum recirculation lines were installed on the High Pressure Safety Injection Pumps to improvc their ability to operate during extended shut-off head operatien.
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o There was no unreviewed safety question since no change in recirculation flow was made.
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PDC 80-11 During this report period selected terminal blocks inside containment were replaced with qualified terminal blocks.
The change did not constitute an unreviewed safety question in that the caeration of the systems were not altered and the terminal blocks were upgraded to meet LOCA and main steam line break environment conditions.
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PDC 80-12 During this report period a parallel valve around HV-V-6 was installed. The valve was to insure that single failure criteria on the hydrogen centrol system was met. The change poses no un-reviewed safety question since the reliability of the system was increased and function of the system was not altered.
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PDC 80-14 During this report period a redundant air charging line for the V.C. was installed to prevent a single failure making the system inoperable. This modification poses no unreviewed safety questics in that the capability of the system to perform its intended safet function and meet single active failure criteria is improved.
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PDC 80-15 During this report period control and power cdbles for selected equipment inside containment were replaced with cable meeting IEEB standards for environmental qualification. The change does not pose an unreviewed safety question in that equipment reliability and plant safety will be increased.
C.
Plant Alterations 1.
The following is a list of those fully approved Plant Alterations requiring a safety evaluation that were implemented during 1930.
a.
PA 79-14 During this report period the discharge of CH-SV-231, a safety valve on the Emergency Feedwater line, was directed to the floor drain and an isolation valve was installed in the deminerali:ed water line to the Low Pressure Surge Tank and Charging Ptelp -
Suction Header. The redirection of the Safety Valve Discharge was to prevent contamination of the demineralized water line and the addition of an isolation valve was to facilitate 9_
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maintenance on system instrumentation and valves. This change I
poses no unreviewed safety question in that the equipment will i
l continue to perform its function.
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PA 79-22 l
L During this report period low flow alarms were installed in the
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ventilation exhaust system for the nuaber 1 and 2 battery rooms f
to alert operators to the potential for hydrogen buildup caused by a loss of ventilation flow. The change does not pose an unreviewed safety question since the system will operate as i
designed and system safety and reliability will be enhanced.
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c.
PA 80-7 During this report period the Shin Condenser h*ater Box gage
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glasses were replaced. The change posed no unreviewed safety j
i question in that the new glasses are more reliable than the l
original since they are easier to read and maintain.
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d.
PA 80-9 i
During this report period a gate valve was installed in the floor drain line between the Auxiliarf Boiler Room and Turbine Building.
The change was to allow the areas to be isolated from each other in the event of a Class "B" fire in either area. The change does not pose an unreviewed safety question La that the drain system has not been degraded and plant safety has been increased.
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PA 80-11 i
I During this report period instrumentation test valves were added to the liquid waste effluent flow transmitter. The change poses i
ao unreviewed safety question in that the operation of the system is the same and the ability to properly calibrate the equipment is i
improved.
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D.
Tests During this report period one test was performed under the requirements of 10 CFR 50.59. The test was performed to verify that a 0 to 20 milliampere current to current isolator would power the bistables of the pressuri er
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pressure channel. The procedure was performed in $bde 5 when the Pressuri:er i
Pressure Channel was not needed, the Channel / System was returned to nomal i
i and all operations of the channel were verified to operate satisfactorily.
Therefore, the test did not pose an unreviewed safety question.
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E.
Experiments 1.
There were no experiments as defined in 10 CFR 50.57 (a) (2).
During this report period there were no challenges to the Pressuri::er or Steam Generator's Safety and Relief Valves, nor were there any failures of those Safety and Relief Valves required to be operable by Technical Specifications.
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