ML20214D014

Annual 10CFR50.59 Rept 1985,Byron Nuclear Power Station, Unit 1

ML20214D014
Person / Time
Site:	Byron
Issue date:	12/31/1985
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20214D011	List: ML20214D008 ML20214D014
References
(0904M-0085M), (904M-85M), NUDOCS 8602210446
Download: ML20214D014 (24)

Text

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B N NUCLEAR P M STATION UNIT 1 ANNUAL 10 CFR 50.59 REPORT 1985 C00000NWEALTH EDISON COMPANY NRC DOCKET NO. 50-454 LICENSE NO. NPF-37 l

8602210446 860131 PDR ADOCK 05000454 R PDR f

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(0904M/0085M)

TABLE OF CONTENTS Modifications PAGES 3-23 I

Test and Experiments PAGE 24 y (0904M/0085M)

I MODIFICATION M6-0-84-049 Description Due to excessive vibration in recirculation line 0FP257A6 the pressure controller which operates valve OFP608 was relocated away from the line.

Safety Evaluation Summary

1. The probability of an occurrtnce or the consequence of an accident, or malfunction of equipment im,ortant to safety as previously evaluated in the FSAR is not increased by the relocation of this pressure controller. This modification does not affect any system important to safety. This modification will, however, increase the level of fire protection by increasing the reliability of valve 0FP608.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. The operation / function of the fire protection system will not be altered by this modification. This modification does not require any new valve line-ups nor will it require any special operating procedures.

3. The margin of safety, as defined in the basis for any Technical Specification, will not be reduced by this modification. Its purpose is to increase the reliability of the fire protection system by ensuring that valve OFP608 closer and opens as required.

(0904M/0085M)

F MODIFICATIONS M6-0-84-140 and M6-0-85-578 Description These modifications were initiated due to a bypass flow concern in the Technical Support Center (TSC) ventilation (M6-0-84-140) system and the Rad Waste Ventilation (M6-0-85-578) System. Check valves were installed in each of the deluge lines to prevent flow from bypassing the charcoal filters.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by these modifications. The operation / functions of the ventilation and fire protection systems will not be changed by these modifications. This modification prevents the possibility for flow bypassing the filters.

2. The possibility for an acc.! dent or malfunction of a different type than any previously evaluated in the FSAR is not created. The addition of these check valves will not decrease the level of fire protection to any area nor will they require special operating procedures. These valves will increase the reliability of the charcoal filter operation.

3. Since the level of fire protection is not decreased and the operation of the systems is not changed, the margin of safety, as defined in the basis for any Technical Specification, will not be reduced.

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(0904M/0085M) i

MODIFICATIONS M6-1-84-153, M6-1-84-164, M6-1-84-165 M6-1-84-173, M6-0-84-170, M6-2-84-221 AND M6-1-84-225 Description These modifications were installed as a result of the final load design documents. These modifications required the addition of new supports / hangers throughout the fire protection system.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by any of these modifications. These new supports / hangers do not affect the capability for safe shutdown of the plant. They will increase the level of fire protection by providing a more reliable fire protection system.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. These modifications will not alter the function / operation of the fire protection or any other plant systems.

3. The margin of safety, as defined in the basis for any Technical Specification, will not be reduced. The addition of these new supports / hangers will increase the margin of safety by providing a more reliable fire protection systen.

(0904M/0085M)

1 MODIFICATION M6-0-84-242 4 Description This modification was performed to assure the minimum required +1/8" i H 2O differential pressure between the control room and the adjacent areas. Blank-offs were installed to remove the lower cable spreading room i,

from the control room ventilatien system. Kitchen and locker room fans j OVC06C, OVC07C, and OVC08C were abandoned in place and recirculation charcoal units were installed in the kitchen and locker room areas.

Duct work for the lower cable spreading room and for the kitchen and locker room exhaust fans were also removed and/or abandoned in place. The technical specifications were revised to delete the lower cable spreading room from the control room boundary. The FSAR will also be revised by project engineering.

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! Safety Evaluation Sununary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The equipment in the lower cable spreading room is qualified at the conditions that exist since the room was deleted from the boundary. The increased pressure within the boundary is conservative and has resulted in an increase in control room pressure.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created, i All equipment is still qualified for the environment in which it exists. The increase in control room internal pressure does not increase the possibility of accident or malfunction incidents.

3. The margin of safety, as defined in the basis for any Technical 4

Specification, is not reduced. Since the technical specifications were 4

revised the control room ventilation system margin has increased.

. System pressure was increased by the modification and still exceeds the

required 1/8" H 20.

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MODIFICATION M6-085-0002 Description This Modification installed bubble-tight dampers OVC32Y and OVC16Y to replace butterfly dampers previously installed. The butterfly dampers were not proven to be leak-tight to limit infiltration of radioactive gases during a design basis accident. The bubble-tight dampers were approved by the NRC to prevent unfiltered in-leakage from exposing operators in the control room above their limits during the design basis accident.

The FSAR will be revised by project engineering to list the outside air dampers as bubble-tight.

Safety Evaluation Summ_a_ry

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The design of the system did not change except that the new dampers allow less leakage than the original butterfly dampers. Fail positions and all other system design parameters were unchanged.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. System design is only improved by allowing less leakage than the original butterfly dampers.

3. The margin of safety, as defined in the basis for any Technical Specifications, is not reduced. Lowering the amount of unfiltered inleakage will reduce operator exposures and will increase the margin of safety.

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MODIFICATION M6-0-85-031 Description The elevation of fire hydrant 0FP28S in the receiving building was lowered in order to provide better accessibility in the event of a fire.

Safety Evaluation Sununary -

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. The receiving building does not contain any safety related or safe shutdown equipment, thus this modification does not impact plant and/or public safety.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. This modification does not degrade the level of fire protection to any area nor does it change the operation / function of the system in the receiving building.

The lowering of fire hydrant 0FP285 only enhances accessibility.

3. Since this modification provides better accessibility to a hydrant that does not protect any safety related or safe shutdown equipment the margin of safety, as defined in the basis for any Technical Specification, is not reduced.

(0904M/0085M)

4 MODIFICATION M6-0-85-043 Description The instrument panel on the diesel driven fire pump was experiencing accelerated wear and tear due to its mounting location and the diesel engine's normal vibration. Utilizing all treaded rods the instrument panel was remounted above the engine.

Safety Evaluation Stamary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. This modification does not decrease the level of the fire protection nor does it impact any other system. This modification provides for reliable instrument readings.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. The operation / function of the diesel driven fire pump will not be changed.

3. The margin of safety, as defined in the basis for any Technical Specification, will not be reduced. This modification will increase the reliability of the fire protection system by increasing the reliability of the data collected from the instrument panel.

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(0904M/0085M)

MODIFICATION M6-1-85-047 Description During the October-December 1985 outage on Unit 1, certain Unit 1 pipe whip restraints on the Feedwater, Main Stream, Reactor Coolant, Residual Heat Removal, and Safety Injection systems were completely or partially removed. This action is subsequent to a January 7, 1985 NRC letter which allows Byron Station to eliminate whip restraints at arbitrary intermediate pipe break locations. Where complete whip restraint removal was determined to be impractical, only the clearance reducing shims were removed at this time. This modification did not require system testing following the removal of the whip restraints.

Safety Evaluation Sununary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The NRC staff no longer requires protection at arbitrary intermediate pipe break locations per staff letter dated January 7,1985 as referenced per the Byron SSER #6. The elimination of pipe whip restraints reduces the probability of piping interferences due to unanticipated piping movements. It has been determined that the elimination of whip restraints at arbitrary intermediate pipe break locations will not affect the capability for safe shutdown of the plant, or jeopardize the health and safety of the public.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. The NRC

> staff no longer requires protection ageinst pipe whip at the arbitrary intermediate pipe break locations. The elimination of whip restraints reduces the possibility of piping interferences due to unanticipated piping movements.

3. The removal of pipe whip restraints at arbitrary intermediate pipe break locations does not reduce the margin of safety as defined in any Technical Specification. The basis of the Technical Specifications do not specifically address whip restraints at arbitrary break locations. However, it is judged that the elimination of the whip restraints at arbitrary intermediate break locations increases the margin of safety, improves system reliability, and improves ALARA considarations due to improved equipment accessibility.

(0904M/0085M)

MODIFICATION M6-0-85-0053 i

Description This modification changes the setpoints for the OB Waste Gas Compressor moisture separator. These setpoint changes are a result of control problems concerning the make up and drain valves. A slight overshoot on the drain and maka up setpoints resulted in valve cycling and erratic compressor operation. The setpoint changes expand the normal moisture separator level and thus eliminate the system oscillations. The normal operating level in '

the moisture separator changed to 60-70% level.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by the setpoint changes associated with the OB Moisture Separator level. The Westinghouse Corp., supplier of the Waste Gas Compressor package, have reviewed the changes in regards to safe operation of the system and they agree that the setpoint changes will not adversely affect the normal system operation.

2. The possibility for an accident or malfunction of a different type that any previously evaluated in the FSAR is not created from the setpoint changes. The modification enhances system operation by maintaining a relatively constant moisture separator level reducing pressure oscillations experienced during automatic make up and drain valve operations. No new equipment, valve line up changes, or special operation procedures will be required as a result of these setpoint changas.

3. The setpoint changes will not reduce the margin of safety, as defined in the basis for any Technical Spscification, since normal Waste Gas system operation is not affected. The Waste Gas analyzers which are governed by Technical Specifications are also not affected and operation will be conducted within specified limits.

(0904M/0085M)

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MODIFICATION M6-0-85-0054 Description This modification changes the setpoints for the OA Waste Gas Compressor

! moisture separator. These setpoint changes are a result of control problems concerning the make up and drain valves. A slight overshoot on the drain and make up setpoints resulted in valve cycling and erratic compressor operation. The setpoint changes expand the normal moisture separator level and thus eliminate the system oscillations. The normal operating level in the moisture separator changed to 60-70% level.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by the setpoint changes associated with the OA Moisture Separator level. The Westinghouse Corp., supplier of the Waste Gas Compressor package have reviewed the changes in regards to safe operation of the system and they agree that the setpoint changes will 4

not adversely affect the normal system operation.

2. The possibility for an accident or malfunction of a different type than i any previously evaluated in the FSAR is not created from the setpoint changes. The modification will enhance system operation by maintaining I a relatively constant moisture separator level reducing pressure oscillations experienced during automatic make up and drain valve operations. No new equipment, valve line up changes, or special operating procedures will be required as a result of these setpoint changes.

! 3. The setpoint changes will not reduce the margin of safety as defined in the basis for any Technical Spedification, since normal Waste Gas System operation is not affected. The Waste Gas analyzers which are governed ,

, by Technical Specifications are also not affected and operation will be conducted within specified limits.

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MODIFICATION M6-0-85-057 Description 5

1 Based on an air flow study conducted by the station's fire protection consultant, three (3) smoke detectors in the control room and one (1) smoke

detector in the Auxiliary Electric Equipment room were relocated to provide optimum coverage.

! Safety Evaluation Summary i

, 1. The probability of an occurrence of the consequence of an accident, or j malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. This modification will not affect the operation of the fire protection system nor will it decrease the level of fire protection in any area containing safety l l related and/or safe shutdown equipment. The relocation of these smoke detectors enhances detection in both the control room and auxiliary electric equipment room.

2. The possibility for an accident or malfunction of a different type than i any previously evaluated in the FSAR is not created. The relocation of these detectors does not introduce any new hazards but rather optimizes the detection system. This change does not require any special test procedure.

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3. Since this modification enhances the reliability of the fire protection l 1 system by providing optimum detection coverage in an area containing safety related and/or safe shutdown equipment, the margin of safety, as j defined in the basis for any Technical Specification, is increased, not l reduced.

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MODIFICATION M6-0-85-126 Description As recommended by the insurance inspector, a new sprinkler system was added to the storage area in the receiving building. The system was designed and installed by a sprinkler contractor and was reviewed by the station's fire protection consultants.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The receiving building does not contain any safety related or safe shutdown equipment, thus this modification does not impact plant and/or public safety.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. This modification increases the level of fire protection to the receiving building while not degrading the operation of the fire protection system in any other area.

3. Since this modification prov2 des a means of fire suppression to an area that does not contain safety related and/or safe shutdown equipment the margin of safety, as defined in the basis for any Technical Specification, is not reduced.

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(0904M/0085M)

MODIFICATION M6-1-85-138 Description This modification involves the addition of 1/4" unions upstream of pressure switches IPS-FP080, IPS-FP081, 1PS-FP082 and OPS-FP166. These unions will facilitate maintenance activities on the pressure switch.

Safety Evaluation Sununary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by the addition of these unions. These unions will enforce the fire protection system by facilitating maintenance activities.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. This modification does not change the operation or function of the system nor does it affect any other system.

3. Since these unions were installed for maintenance purposes only, and they do not affect the system, the margin of safety, at defined in the basis for any Technical Specification, is not reduced.

(0904M/0085M)

MODIFICATION M6-085-0166 Description This Modification installed bubble-tight dampers OVC312Y and OVC313Y to replace butterfly dampers previously installed. The butterfly dampers were not proven to be leak-tight to limit infiltration of radioactive gases during a design basis accident. The bubble-tight dampers were approved by the NBC to prevent unfiltered in-leakage from exposing operators in the control room above their limits during the design basis accident.

The FSAR will be revised by project engineecing to list the outside air dampers as bubble-tight.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The design of the system did not change except that the new dampers allow less leakage than the original butterfly dampers. Fail positions and all other system design parameters were unchanged.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. System design is only improved by allowing less leakage than the original butterfly dampers.

3. The margin of safety, as defined in the basis for any Technical Specifications, is not reduced. Iowering the amount of unfiltered inleakage will reduce operator exposures and will increase the margin of safety.

(0904M/0085M)

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l MODIFICATION M6-1-85-0181 i

l Description i

i This irodification pertains to replacement of the existing shunt trip attachinents on the breakers in the Reactor Trip Switchgear, and the  !

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, installation of Auto Shunt Trip Panels per Westinghouse FCN's CAEM 10807

& 10808. The snodification is a part of the action required by NRC i

l Generic Letter 83-28 section 4.3.

The original Westinghouse Reactor Trip design utilized an undervoltage (W) coil for automatic trips from the Solid State Protection System.

1 For manual trips a shunt coil was used in conjunction with the W coil.

l The modification involved the installation of an Automatic Shunt Trip i Panel that provides for shunt coil and undervoltage coil operation on manual and automatic reactor trip actuations. The panel also provides I switches and test points to aid in undervoltage and shunt coil testing. ,

Safety Evaluation Susunary .

l The probability of an occurrence or the consequence of an accident or l 1..

] malfunction of equipment important to safety as previously evaluated i

in the FSAR is not increased. The modification enhances the '

operability of the Reactor Trip Breakers as an additional tripping

, feature is employed during an automatic trip. Figure 7.2-1 of the l FSAR will be revised to demonstrate this added feature.

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2. The possibility of an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. The modification aids in preventing an Anticipated Transient without j scram event by adding another tripping feature to the breaker. The j modification satisfies item 4.3 of NRC Generic Letter 83-28. Byron

License Condition 2.C.11 covers the implementation of NRC Generic

{ Letter 83-28.

I i 3. The margin of safety, as defined in the basis for any Technical l

! Specifications, is not reduced. The margin of safety is increased by 7 j the installation of this modification as it increases the nusaber of j trip features employed by an automatic trip signal.

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MODIFICATION M6-1-85-425 Description This modification adds temperature switches in the Blowdown Condenser room and where the blowdown piping from the Main Steam tunnel penetrates the Aux Building wall. A signal from any one of the temperature switches will initiate a Control Room alarm and close Steam Generator Blowdown Isolation valves ISD002B, D, F and H when a predetermined high ambient temperature is reached in either of the afore mentioned areas. The temperature switches are necessary to assure that qualification temperatures of safety related equipment are not exceedad due to a high energy line break in the Steam Generator Blowdown System.

i Safety Evaluation Summary i 1. The probability of an occurrence or the consequence of an accident, or

, malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. A high temperature interlock has been added to the Steam Generator Blowdo*fn Containment Isolation valve logic to isolate upon sensing a high temperature environment that could affect equipment located in the area. The blowdown valves ISD002A-H maintain their safety function of isolating containment upon a Phase A isolation signal.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created by the installation of the high temperature interlock with the Steam Generator Blowdown valves ISD002A-H. The consequences of equipment degradation as a result of a high energy line break are reduced through the implementation of this interlock.

3. The installation of the high energy line break interlock associated with the Blowdown Containment Isolation valves ISD002A-H increases the margin of safety, as defined in the basis for any Technical Specification, by insuring that equipment required for safe shutdown will not be exposed to adverse environmental conditions.

i (0904M/0085M)

MODIFICATION M6-0-85-426 Description This modification requires the addition of a 4" isolation valve on line 0FP11BB-12. This isolation valve will be used as a tie in for the new Unit 2 track bay sprinkler system, as recommended by the insurance inspector.

Safety Evaluation Summary

1. The pecbability of an occurrence or the consequence of an accident or malfunction of squipment important to safety as previously evaluated in the FSAR is not increased by this modification. The level of fire protection to any given area will not be changed nor will this addition affect any other system.

2. The possiDility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. The fire protection system will continue to function as required. No new hasard will be introduced nor will the operation of the fire protection system be changed.

3. Since this 4" isolation valve will in time be used as a tie in for the new U-2 track bay system, it is considered an enhancement to the fire protection system, therefore, the margin of safety, as defined in the basis for any Technical Specification, will not be reduced, i

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MODIFICATION M6-0-85-463 Description This modification was initiated as a result of incomplete construction. The floor of the upper cable spreading rooms are equipped with access hatches which lead down to the control room. These hatches did not meet the required fire rating therefore a thornofiber blanket was laid over each hatch. This configuration was reviewed and approved by the station's fire protection consultants.

Safety Evaluation Sununary ,,

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. .This modification will provide the 3 hr. fire rating required by the Byron Fire Protection Report.

2. The possibility for an accident or ma15 unction of a different type than

i any previously evaluated in the FSAR is not created. This modification does not introduce any new hazards nor does it. decrease the levet of fire protection in other areas. The thermofiber blankets will restore i the upper cable spreading room floor to its required fire rating.

3. This modification ensures the upper cable spreading room floor complies with the Byron Fire Protection Report. The thermofiber blankets do not reduce the margin of safety, as defined in the basis for any Technical Specification.

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(0904M/0085M)

4 MODIFICATION M6-1-85-475 Description This modification was initiated by the station's Fire Marshal. Fifty (50) feet of fire hose was added to the existing 50 ft. on hose station 113 on the 383' elevation in the Auxiliary building.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by the addition of 50 feet of fire hose. The addition will have no affect on plant operation but will increase the level of fire protection by optimum fire suppression coverage.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created. the normal function of systems involved in the operation of the plant will not be altered. This modification will provide manual fire suppression to previously inaccessible areas.

3. Since this modification increases the level of fire protection /supprsssion on the 383' elevation and does not impact on any other system, the margin of safety, as defined in the basis for any Technical Specification, is not reduced.

i (0904M/0085M)

t MODIFICATION M6-1-85-490 Description During the October-December 1985 outage on Unit 1, modifications were performed on the hatch assemblies of the reactor inspection cavity annulus to reduce neutron scattering ef.fects. The modification consisted of lowering the hinge pin holes on the existing hinge posts to allow the hatches to be installed in the closed position (flange seals unbolted) during normal operations. This modification did not require system testing.

Safety Evaluation Sununary

1. The probability of an occurence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased. The structural loading of the components is not affected and the hatches remain hinged to provide pressure relief into the main containment area as previously evaluated in the FSAR.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the PSAR is not created. The lowering of the hatch to the top of the cavity affects the reactor cavity ventilation flowpath. This condition has been evaluated and does not introduce an accident or malfunction scenario differing from that previously evaluated in the FSAR.

3. The modification to the reactor inspection cavity hatch assemblies does not reduce the margin of safety as defined in any Technical Specification. Structural loading to the cavity and liner is unaffected. The reactor cavity ventilation subsystem is non-safety related and is not required to operate following a LOCA or for safe shutdown of the plant.

(0904M/0085M)

6 MODIFICATION M6-1-85-567 Description This modification is required to provide redundant isolation of Steam Generator Blowdown in the event of a High Energy Line Break in the Aux Building portion of the Steam Generator Blowdown piping. The addition of valves ISD054A through H in series with the existing ISD002A through H valves will provide this redundant protection. The ISD054 valves also assume the flow control function originally assigned to the ISD002 valves.

Removing the control function from the ISD002 valves will prevent possible damage to the valve seats and thus enabling them to properly serve their containment isolation function.

Safety Evaluation Summary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR is not increased by this modification. Valves have been installed in series with the Blowdown Containment isolation valves, ISD002's, to control blowdown flow and to provide redundant isolation upon sensing a high energy line break. This interlock will prevent environmental conditions in certain areas in the Aux Building from exceeding environmental parameters that could adversely affect equipment located therein.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR is not created from the installation of the additional blowdown valves (ISD0564A-H). The modification will enhance system operation by assuming the flow control function originally assigned to the ISD002 valves. The consequences of equipment degradation created by a high energy line break, such as with the steam generator blowdown piping, has been reduced through the implementation of this modification.

3. The installation of the redundant isolation valves on the steam generator blowdown piping increase the margin of safety, as defined in the basis for any Technical Specification, by insuring that equipment required for safe shutdown will not be subjected to adverse environmental conditions.

(0904M/0085M)

i SPECIAL PROCEDURE SPP 84 3 Description On October 24, 1984, Special Procedure SPP 84-1 was completed. This involved the movement of two primary sources from temporary storage and installation into fuel assemblies. This procedure was conducted to support Byron Station Unit One initial core load.

Safety Evaluation Simmary

1. The probability of an occurrence or the consequence of an accident, or malfunction of equipment important to safety as previously evaluated in the FSAR was not increased by the performance of this special procedure. This procedure was conducted prior to initial core load, the unit was not operating, and no unusual or unanalyzed valve or equipment configurations existed. Further, neutron source handling accidents are not evaluated in the FSAR.

2. The possibility for an accident or malfunction of a different type than any previously evaluated in the FSAR was considered because neutron source handling accidents of this type are not evaluated in the FSAR.

An evaluation regarding the safe performance of this procedure was conducted as part of the.onsite review process prior to performance of this special procedure. The procedure was consistent with the precautions and limitations of Specia.1 Nuclear Material License SNM 1917 which governed storage of fuel assemblies in the Spent Fuel Pit. A detailed ALARA review was performed along with several rehearsals of the procedure to reduce the radiation dese received by station personnel.

Finally NRC resident inspector J. Hinds was contacted and provided with a copy of the procedure. He concurred that the procedure was acceptable prior to its execution.

3. The performance of this special procedure did not reduce the margin of safety, as defined in the basis for any Technical Specification.

Although not in effect, a draft of Technical Specifications regarding storage and leak testing of sources was observed in the performance of this procedure.

(0904M/0085M)

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