ML20214E128

Fourth Annual 10CFR50.59 Rept VC Summer Nuclear Station

ML20214E128
Person / Time
Site:	Summer
Issue date:	05/07/1987
From:	Nauman D SOUTH CAROLINA ELECTRIC & GAS CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 8705210669
Download: ML20214E128 (11)

Text

., 10CFR50.59 A.

ggy Electric & Gas Company Nuclear Operations

.gygsg29218 May 7, 1987 Dr. J. Nelson Grace Regional Administrator U. S. Nuclear Regulatory Commission Rr:gion II, Suite 2900 IJ1 Marietta Street, N.W.

'(tlanta, Georgia 30323

Subject:

Virgil C. Summer Nuclear Station Docket No. 50/395 Operating License No. NPF-12 Annual 10CFR50.59 Report

Dear Dr. Grace:

Attached is the fourth Annual Report provided pursuant to 10CFR50.59(b) for the Virgil C. . Summer Nuclear Station. This report includes a brief description of modifications made to the facility as described in the Final Safety Analysis Report (FSAR) and a summary of the safety evaluation of each.

These modifications, identified by the Modification Request Form (MRF) number where applicable, were completed prior to August 6, 1986, which ended the fourth year following the issuance of the Facility Operating License.

If you have any questions, please advise.

ery ul yours,

.A ua HIO/ DAN:jez Attachment c: 0. W. Dixon, Jr./T. C. Nichols, Jr. C. L. Ligon (NSRC) l E. C. Roberts R. M. Campbell, Jr.

O. S. Bradham K. E. Nodland J. G. Connelly, Jr. R. A. Stough D. R. Moore G. O. Percival

W. A. Williams, Jr. R. L. Prevatte i Group Managers J. 8. Knotts, Jr.

l W. R. Baehr I&E Washington

! C. A. Price NPCF W. T. Frady File 8705210669 870507 PDR ADOCK 05000395 R PDR ,

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FOURTH ANNUAL 10CFR50.59 REPORT VIRGIL C. StM9ER NUCLEAR STATION MRF-10441 This modification added ladders and associated platform steel to provide direct access to the floor area around the Recycle Hold-up Tank to allow easier access. The platforms and ladders will not impact on safety equipment in a seismic event; therefore, the modification did not affect the plant margin of safety.

MRF-10470 This modification installed additional in-line isolation valves for back-up leakage protection on the vent and drain lines of the Seal Water Injection Filters A&B. Addition of these valves enhanced the existing isolation valves and aided in reducing undetected leakage. Therefore, with this increased reliability in leak rate detection, the margin of safety was increased.

MRF-10585 This modification constructed a new building, the Auxiliary Service Building. The Auxiliary Service Building provides an extension of plant administration and computer expansion needs. The building was evaluated to be consistent with plant guidelines in accordance with FSAR requirements. This modification had no effect on plant safety.

MRF-10638 This modification provided for the addition of a backflush connection on the Excess Liquid Waste Demineralizer Tank, XDM36-WX, to provide a means for unclogging the Johnson Screen in the tank's vent. The modification assures a more efficient operability status when flow rates are being established. The margin of safety has been enhanced by this modification.

MRF-10681 This modification added a larger waste compactor for compacting radioactive dry westes in 90 cu. ft. box containers instead of 55 gallon drums (the drum compactor will be used as a standby unit). The larger waste compactor has the capability for greater volume reduction; therefore, the total volume of compacted wastes will be reduced and substantial cost savings will be realized. This also means greater commitments to radwaste volume reduction and ALARA. The waste compactor is not required for safe shutdown of the plant; therefore, the margin of safety was not affected.

MRF-10698 This modification made a direct connection of the vendor solidification system and dewatering system vents to the plant ventilation ductwork. The modification enhanced the capture of radioactive off gas during radwaste processing and did not reduce the margin of safety.

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.MRF-10702 This modification added test' connectors .to the feedwater flow venturi. ~The changef allows monitoring feedwater flow with a l~ high accuracy differential pressure sensor during performance testing. Utilization of the connections is procedurally controlled to prevent any adverse impact on the plant, and the plant's margin of safety was not reduced.

MRF-10741 This modification increased the overflow nozzla of the Floor Drain Tank and piping from 2" to 6". The vent-line low point was provided with a. drain line with a water loop - seal. The modification involved non-safety.. equipment and piping. The

margin of safety was not decreased.

L MRF-10759 This modification adde'd cooling coils to the inlet ductwork on the Service Water Pumphouse HVAC System. The . coils receive 7 water from the Service Water System _which cools the incoming air. The coils prevent the air temperature -in the 'pumphouse from ' exceeding the temperature limit as defined in Technical Specifications. The operation of the cooling coils was determined not to have an adverse effect on either the Service

, Water System or Service Water Pumphouse HVAC System.' The margin of-safety was not reduced.

MRF-10827 This modification - replaces a swing check valve with a spring loaded check. valve for better fluid control. Poor maintenance history on the previous valve and clarifier sump pump problems necessitated the change. The change . improved the reliability

, and performance of the clarifier' sump system.. The . system is entirely non-safety; - therefore, the margin of safety was not affected.

MRF-10858. This modification revised the alarm setpoints and circuitry on

-the RHR pump room and waste evaporator feedpump sumps in order to eliminate false alarms. The sump start setpoint was lowered on the larger downstream collection sump in order _ to i prevent back drainage into the sumps. This modification did

. not reduce the margin of safety.

MRF-10905 This modification relocated the plant's communication repeater

+ transmitters. The improved environmental conditions reduce the possibility of communication equipment failure. The margin of safety was not decreased.

i MRF-10908 This modification removed an alarm located on the main control

! - board for the demineralized water makeup system. The alarm and the water treatment system are non-safety and do not serve any safety related function; therefore, the margin of safety was not reduced.

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'MRF-10919 This modification removed the Dead Weight tester, which was an I&C test instrument to check the calibration of the Pressurizer pressure channels. This hardware was never fully installed and never utilized. It was removed to prevent confusion and thus help prevent improper maintenance activities and eliminate unnecessary containment penetration testing. The margin of safety was not reduced.

MRF-20032 This modification to the Diesel Fire Pump Engine cooling water supply piping and valves improved system reliability by lowering engine operating temperatures. The margin of safety was not reduced.

MRF-20038 This modification added a cooling unit to provide cooling for room AB 63-01 which contains 10B switchgear safe shutdown equipment. This modification was installed to reduce heat related failures, maintain the equipment's qualified life, and to satisfy Technical Specifications temperature limits for this area. The unit is non-safety but is mounted seismically in the room to prevent "falldown" and damage to safety related equipment during seismic events. The margin of safety was not reduced.

MRF-20058 This modification removes the existing fire protection equipment (wet pipe sprinklers) from the Service Building

. telephone equipment room, and replaces it with a Halon 1301 fire protection system. The wet pipe sprinklers were removed to prevent water related damage to the equipment. The system is non-nuclear safety related and the margin of safety was not reduced.

MRF-20168 This modification added a recirculation loop and a chemical feed system to the sodium hydroxide tank of the Reactor Building Spray System. This permits improved mixing of the tank contents prior to required Technical ' Specifications sampling as well as during chemical addition and therefore maintains the concentration of sodium hydroxide uniform throughout the tank. The margin of safety was not reduced.

MRF-20179 This modification adds a 5000 gallon collection tank for collection and holding of water from the RWST sump. The water from the tank is sampled and, if acceptable, discharged to the yard drainage system. This modification was made to the non-safety, non-nuclear drain system; therefore, the margin of safety was not reduced.

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MRF-20208- This modification provided a method to actuate the Reactor Trip Switchgear's (only RTA & RTB) shunt trip attachment on an automatic reactor trip signal. The addition of the auto shunt .

tr.ip capability was accomplished because of reliability concerns regarding the ability of the Reactor Trip Switchgear undervoltage trip attachment. to open the breaker. The ,

addition .of auto shunt trip capability- increases the-reliability of the Reactor Trip 1 Switchgear to open on an automatic reactor trip signal because of redundant trip devices and therefore improves the margin of safety.

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MRF-20243 This modification added a " kidney loop" to .the - condensate system to provide for condensate polishing at power levels greater than 50%. Two pumps are provided to pump water from the condenser hotwell through the condensate polishing system and back to the condenser hotwell. This modification of a non-safety system did not reduce the margin of safety.

MRF-20297 This modification added sterile water treatment equipment to the existing Construction Potable Water System . and upgraded the existing system to comply with State drinking water regulations. The Construction Potable Water System .is classified as non-safety and non-seismic; therefore, the margin of safety was not affected.

MRF-20364 This modification provided physical fitness areas (i.e.,

, running track exercise area) outside the plant protected area boundary for the plant security force. This was done to allow t

the security force to implement their fitness program in more appropriate areas. These landscaping changes have no effect

. on any plant hardware and therefore have no impact on the l' margin of safety.

.This modification added jib cranes over the three (3) Reactor MRF-20368

, Coolant pump openings and over the Refueling Cavity in the 4

Reactor Building. The purpose of .the modification was to assist maintenance during outages and reduce dependence on the slower moving Polar Crane. The modification did not have any impact on safety related equipment and did not reduce the margin of safety.

MRF-20546 This modification added handrails around manholes in the l' Service Water and Diesel Generator Buildings. These handrails were 'added to increase personnel safety in vicinity of the manholes. The handrails were designed to withstand a seismic event. Therefore, they had no impact on plant safety equipment, and did not reduce the margin of safety.

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[ MRF-20555 This modification revises the commitments for "1E" "NON-lE" circuit separation in cases of multiple violations of redundant trays by ~a single NON-1E tray. The required protection is. new obtained by barriers or' by breaker testing, as appropriate. FSAR Appendix 8C.provides an evaluation which

, justifies the . separation as originally designed.. .This modification documents separation barriers & testing beyond that required. Therefore, the margin of safety was increased, t

. MRF-20576. This modification provided isolation of the chilled water to

the charging pumps lube oil- system when the pumps are not running to prevent moisture build-up in the lube oil system due to - condensation. The isolation valves are designed to fail open to assure cooling to the system upon isolation valve failure. . Valve position indication is provided .on .the Main

. Control Board as well as alarm points for valve failure on running pumps. . This modification provides a more reliable system by. eliminating moisture problems. Therefore.- the margin of safety was not reduced.

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- MRF-20580 This modification revised drawings to indicate that certain' -

specific sample valves shall.be locked open. These valves are designated as locked open for both normal and post accident sampling purposes. These drawing changes provide necessary clarification to Operations personnel. The nature of these changes decrease the probability of an occurrence / accident and therefore did not reduce the margin of safety.

- MRF-20586 This modification was initiated due to a need to clarify associated Emergency Core Cooling System check valve testing flow diagrams to aid operations personnel in performing tag-

, outs. The nature of this change decreased the probability of 4

an occurrence / accidents and therefore did not reduce the margin of safety.

MRF-20593 This modification added a pancake blank flange at the filtered ,

water / condensate cross connection to prevent chloride in the filtered water system from entering the secondary system.

- This modification improves station overall reliability by preventing . a potential chloride contamination .of the steam generators; therefore, the margin of safety was not reduced.

MRF-20645 This modification provided radiation gates in the Reactor Building and on the Intermediate Building roof. The purpose of the modification was to restrict access to radiation areas to ensure no unnecessary exposures to plant personnel. The 4 gates have been designed in accordance with applicable seismic criteria where failure could impact safety equipment.

Therefore, plant safety has been maintained with the gate addition and the margin of safety was not reduced.

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MRF-20652 This modification was initiated to revise miscellaneous essential and non-essential drawings. These drawing changes have been made to correct the drawings in those instances where the drawings did not reflect the as-built configuration of the plant as well as instances where errors existed. These drawings decrease the probability of an occurrence / accident because the revised drawings more accurately reflect the as-built configuration of the plant and therefore the margin of safety was not reduced.

MRF-20687 This modification constructed a new building, the Radiological Maintenance Building. The Radiological Maintenance Building provides an extension of the existing Hot Machine Shop, calibration facilities, and tool room. The building was evaluated to be consistent with plant guidelines in accordance with FSAR requirements. This modification had no effect on plant safety.

MRF-20690 This modification added a 480V unit substation to provide 480 volt power for new buildings and future load growth. The addition of this non safety related substation had no adverse effect on the station electrical power system. The substation will not affect the safety related systems of the plant and therefore the margin of safety was not reduced.

MRF-20708 This modification involved drawing changes only to reflect current as-built configuration of the plant. Breaker / Starter units for Motor Control Center XNC1082X-ES were shown incorrectly on the design drawings and in the FSAR. The margin of safety was not reduced.

MRF-20718 This modification involved a drawing revision to show the as-built configuration of fire dampers. This revision did not increase the probability of an occurrence or consequences of an accident; therefore, the margin of safety was not reduced.

MRF-20722 This modification provided piping additions to the underground fire service loop to support sprinkler systems installed in the new Auxiliary Service and Radiological Maintenance Buildings. The margin of safety was not reduced.

MRF-20730 This modification was a document revision to reflect the present HVAC operating conditions of the pressurizer cubicle.

The changes were a result of the inability of current operating parameters to supply the design quantity of air flow. The reduced flow rate has been analyzed and verified to be within the design limits of providing cooling to the l pressurizer compartment components. The evaluation performed i was within the safe limits of the HVAC requirements of the Reactor Building Cooling System. The margin of safety was not reduced.

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t A l MRF-20732 This modification was initiated to revise an essential drawing. The design flags for feedwater check valves XVK-1633A,B&C' were incorrectly shown. This drawing change

. decreased the probability of an occurrence / accident because the revised drawing accurately reflects the as-built configuration of the plant. The margin of safety was not reduced.

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',t MRF-20735 This modification installed an access platform on the auxiliary building roof to provide a means of personnel access '

over an HVAC duct and therefore improve personnel safety in the area. The design was such that the platform could not i

impact any plant safety equipment. The margin of safety was not reduced. ,

i MRF-20745 This modification was initiated to permanently remove the l Westinghouse hot crud sampler and return it to ' Westinghouse for installation at Watts Bar for testing purposes. This equipment's function was for vendor testing only. The margin of safety was not reduced. s MRF-20751 This modification added a spool piece and flange tothe [

condensate storage tank drain to prevent inadvertent leakage (

of the storage tank through a valv6. The design meets all ,

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applicable seismic and pressure requirements. The margin of '

safety was not reduced. '

MRF-20755 This modification removed a non-safety, non seismic wall to g make a larger, less congested working conference room. The 'i removal of the non-fire wall did not affect any essential equipment in the area and the margin of safety was not decreased. o MRF-20769 This modification was a drawing revision which relocated hydro boundaries closer to the reheat letdown heat exchanger in the Boron Thermal Regenerative System. The previous boundaries were welded adapters which could not be isolated; therefore, the drawing hydro flags were moved to valves that could be 'q closed in order to perform the required ASME Section XI Hydro <

Test. The boundary relocation did not affect the system s operation, components, or reliability and did not reduce the < o margin of safety. (

MRF-20813 This drawing modification corrected ortrenumbered room numbers i due to inconsistencies that existed between room numbers on s the various plant layout drawings. Safety related equipment <

was not affected by this modification and therefore the margin . , ..'

of safety was not affected. ,

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MRF-2g816 This modification added adequate. backup containment

. penetration overcurrent protection devices to various control circuits to comply with Regulatory Guide 1.63.. The' margin of ,

g, safety was increased by the addition of the backup containment penetration overcurrent protection ' because the likelihood of containment penetration damage from overcurrents was reduced. >

J MRF-20825 [ llhis modification was . initiated to add two additional catch

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',Abasinsfor yardthe drainage in anStorageeffort Tank to' eliminate standing 7 s water around Condensate and the Circulating

,, 6 t 1 Water Intake Structure. The margin of safety was;. unaffected.

MRF-20831 ' . This modification added aldeaerator storage tank temperature

< ' gindicator to the main ccatrol board (XPN-6112) near the 'c

? feedwater booster pump section. Mir,or regrouping of q indicators was also required to provide' for 'a' good human 5

engineered design. The existing storage tank thermocouple was

}g replaced with a Resistance Temperature Detector that could drive both the Main Control Board indicator and provide input'

. to the plant computer. The Feedwaterj System Operation was t enhanced by the additional information provided to the Control '

t Room Operator and therefore the margin of safety was not reduced. ,

g MRF-20846' TMs drawing ;modificttion resulted fron , a field inspection

( which indicated the, frame sizes .on four (4) feeder breakers

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located in the OCybistribution Panels? pere not in agreement with the applicabit drawings. , The mod.f fication was a drawing revision

• only and did not decrease.or affect the margin of safety.

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p MRF-20858 This modification resulted in sthe Non-Nucle &r Safety battery bank 1 being replaced with a higher amp-hour capacity battery.

Battery bank I's condition was degrading because of copper contamination to the battery cell plates. TheLhigher amp-hour

[t, apacity battery provided power to selective loads for two

'Ihours which are greater than the one hour FSAR requirement. '

The, margin of safety was not reduced.

4 4 MRFNS369 This (modification separated the Channel I 1. cads and allowed i

each distribution bus to be fed from its own Chmnel I,

+ - - Inverter to eliminate a load related problem experienced on d '

7the Channel I instrument bus during equipment start-up. c Both <

Channel I distribution buses were originally fed by one inverter. The new scheme for the Channel I instrumentation

(; and control power supply system will satisfy the Technical reliability and

, ,(, Specification the margin of safety.requirements \any enhance plant f -

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' MRF-20893 This modification : installed and removed a -temporary penetration for services ' ta support steam generator repairs during an outage. The margin of safety was not reduced.

MRF-20936 This modification was a drawing revision that added a note to drawings- with temporary strainers : on them. This note was added to ensure that drawings used to operate the plant represent the actual plant design. Since the modification was a drawing change only, the margin of safety was not reduced.

MRF-20969 This modification was a drawing change to eliminate-Westinghouse flow diagrams from the drawing control system and to modify the -notes on the G/C flow diagrams to prevent duplication. The margin of safety was not affected since all i; the design information .was verified to be ' properly incorporated.

MRF-20994 This modification was a document change only to' clarify the interlocks which exist in the Service Water and Component Cooling Systems. The modification of the system design descriptions improved understanding of the design intent and

. helped in improving safe operation of the Service Water and Component Cooling pumps. The margin of safety was not reduced.

N'/A This change to the Final Safety Analysis Report (FSAR) resulted from a Technical Specifications revision to define 4

the required shutdown margin as a function of Reactor Coulant System boron concentration. This change was made to allow use

.of a 18 month low-leakage fuel management scheme. The change i is not an unreviewed safety question because the margin of

! safety is maintained by holding the time for operator action in the event of an inadvertent boron dilution at or in excess l

of that stated in the FSAR.

' N/A These changes updated the Fire Evaluation Report Manual to include a reanalyzation of recent interpretations relative to 10CFR50, Appendix R. The' margin of safety was not reduced.

N/A 'This change deleted the words "part length control rods" in Sections 7 and 11 of the- Final Safety Analysis Report since part length control rods have never been used. This editorial correction did not affect the plant design or safety analysis.

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N/A This; change to the Final Safety Analysis Report resulted from  !

a Technical Specifications revision to upgrade the design bases to include the effects of steam generator tube plugging (up to 6%). - This change was required to support continued i operation in the event a significant number of tubes must be plugged. The steam generator tube plugging resulted in a 1 decrease in thermal design flow due to increased flow resistance. Westinghouse performed a new LOCA analysis using the BART code with 6% plugging, used generic DNBR margin to offset the impact of the reduced' flow, and concluded that the existing safety analysis remains applicable. With steam generator tube plugging to 6%, adequate plant safety margins are maintained.

N/A This change to the Final Safety Analysis Report reflects the recent qualification of Drillco Maxi-Bolts for use along with Hilti expansion anchors. Maxi-Bolt expansion anchors have capabilities which will prove useful in certain applications.

The bolts have been qualified and tested on site in accordance with the applicable guidelines and the Quality Assurance program. The margin of safety was not reduced.

N/A This change to the Final Safety Analysis Report involved an evaluation of increased feedwater valve closure times compared to the original conservative analysis. The 10 second feedwater isolation - time limit in Table 3.3-5 Engineered Safety Features Response Times, was not exceeded; therefore, the margin of safety was not reduced.

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