ML20246P608

Forwards Summary of 890712 Meeting w/C-E Owners Group & Utils Re General Design Features of Diverse ESFAS to Be Installed,Per 10CFR50.62.Safety Evaluation on Plant Design Expected to Be Issued in Near Future

ML20246P608
Person / Time
Site:	Waterford
Issue date:	09/06/1989
From:	Wigginton D Office of Nuclear Reactor Regulation
To:	Dewease J LOUISIANA POWER & LIGHT CO.
References
NUDOCS 8909110181
Download: ML20246P608 (3)

Text

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. September 6, 1989 4

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Docket No. 50-382 Mr. J. G. Dewease Senior Vice President - Nuclear Operations Louisiana Power and Light Company Post Office Box 60340 New Orleans, Louisiana 70160

SUMMARY

OF MEETING WITH COMBUSTION ENGINEERING OWNERS GROUP (CE0G) REGARDING THE DEFAS DESIGN FEATURES TO BE INSTALLED PER 10 CFR 50.62 (THE ATWS RULE)

On July 12, 1989, a meeting was held with the NRC and representatives of four licensees who form the CEOG on the ATWS rule. Enclosed is a summary of that meeting for your information. The Safety Evaluation on the Waterford design is expected to be issued in the near future.

If there are any questions in this regard, please let us know.

Sincerely,

/s/

David L. Wigginton, Project Manager Project Directorate IV Division of Reactor Projects - III, IV, Y and Special Projects Office of Nuclear Reactor Regulation

Enclosure:

As stated cc w/ enclosure:

See next page DISTRIBUTION.

DocketiW! NRC PDR Local PDR PD4 Reading G. Holahan ADR4 F. Hebdon P. Noonan D. Wi ginton 0GC-Rockville E. Jordan B. Grimes ACRS 10) PD4 Plant File

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September 5, 1989

Docket No. 50-382 Mr. J. G. Dewease Senior Vice President - Nuclear' Operations Louisiana Power and Light Company Post Office Box 60340 L

New Orleans, Louisiana 70160

SUMMARY

OF MEETING WITH COMBUSTION ENGINEERING OWNERS GROUP (CEOG) REGARDING THE DEFAS DESIGN FEATURES TO BE INSTALLED PER 10 CFR 50.62 (THE ATWS RULE).

On July 12, 1989, a meeting was held with the NRC and representatives of four licensees who form the CEOG on the ATWS rule. Enclosed is a sumary of that meeting for your information. The Safety Evaluation en the Waterford design is expected to be issued in the near future.

If there are'any questions in this regard, please let us know.

Sincerely, ,

/ i u

David L. Wigginton, Project Manager Project Directorate IV Division of Reactor Projects - III, IV, Y and Special Projects Office of Nuclear Reactor. Regulation

Enclosure:

As stated cc w/ enclosure:

See next page 4

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_---_-___-_____-__-___:____=____-___________________-_____-________-_-__-______-______-_-__-______-____-________-__-_

Mr. Jerrold G. Dewease Waterford 3 l . Louisiana Power & Light Company l

l cc:

W. Malcolm Stevenson, Esq. Regional Administrator, Region IV Monroe & Leman U.S. Nuclear Regulatory Commission 201 St. Charles Avenue, Suite 3300 Office of Executive Director for New Orleans, Louisiana 70170-3300 Operations 611 Ryan Plaza Drive, Suite 1000 i

Mr. E. Blake Arlington, Texas 76011 l

Shaw, Pittman, Potts & Trowbridge 2300 N Street, NW Hr. William H. Spell, Administrator Washington, D.C. 20037 Nuclear Energy Division Office of Environmental Affairs Resident Inspector /Waterford NPS Post Office Box 14690 Post Office Box 822 Baton Rouge, Louisiana 70898 Killona, Louisiana 70066 Mr. Ralph T. Lally President, Police Jury Manager of Quality Assurance St. Charles Parish Middle South Services, Inc. Hahnville, Louisiana 70057 Post Office Box 61000 New Orleans, Louisiana 70161 '

Chairman William A. Cross Louisiana Public Service Commission Bethesda Licensing Office One American Place, Suite 1630 3 Metro Center Baton Rouge, Louisiana 70825-1697 Suite 610 Bethesda, Maryland 20814 Mr. R. F. Burski Nuclear Safety and Regulatory Affairs Manager Louisiana Power & Light Company 317 Baronne Street New Orleans, Louisiana 70112

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Docket Nos: 50-361 50-362 50-368 50-382 50-528 50-529 50-530 t:EMORANDUll FOR: John N. Hannon, Director Project Directorate III-3 Division of Reactor Projects - III, IV, V and Special Projects FROM: M. David Lynch, Senior Project Engineer Project Directorate III-3 Division cf keactor Projects - III, IV, V and Special-Projects

SUMMARY

OF MEETING WITH THE COMBUSTION ENGINEERING OWNERS GROUF (CEOG) REGARDING THE DEFAS DESIGN FEATURES TO BE If4STALLE0 PER 10 CFR 50.62 (THE ATWS RULE)

A meeting was held in Cethesca, Maryland on July 12, 1509, between members of the NRC staff and. representatives of four licensees who form the Combustion Engineering Owners Group (CEOG). The four licensees are: Louisiana Power &

_ Light Cen.pany (Waterford); Arkansas Power & Light Company (ANO-2); Southern Califernia Edison Company (San Onofre 2 & 3} and Arizona Public Service Company (Palo Verde 1, 2 & S). A list of attendees is presented in Enclosure 1.

.Eackground A previous meeting with the CEOG was held on May 1, 1989, te discuss the general cesign. features of the oiverse emergency-feeowater actuation system-(DEFAS) portion of the ATWS equipment to be installed per the requirements of 10 CFR 50.62. The meeting on May 1, 1989, discussed the overall approach by the CEOG in designing the DEFAS as contained in the report, CE NPSD-384, which was docketed on April 30, 1989. There was a subsequent telephone conference on June 21, 1989, between the NRC staff and representatives of the CEOG which was focused on six concerns identified by the staff regarding the overall design features of the DEFAS. It was agreed by the parties to this telephone conference that these six concerns would form the agenda for the meeting to be held on July 12, 1989.

Contr.ct:

H. Li (SICB/ DEST), X-20781 D. Lynch (PD/3-3), X-23023 l

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"Jphn N. Hannon Sumary The staff concluded early in the meeting on July 32 as a result of the CEOG presentation that there would be such differences in the DEFAS equipment to be insta11eo by the four Mcensees that a finc1 NRC acceptance of the DEFAS desigr, features could only be viven followine a staff review of the plant specific

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submittals. On this basis, the staff will r.ct issue a generic SER on the CE report citec above. However, there was sufficient information presented in the meetings on May I and July 12, 1989, to permit the staff to make specific coments on the DEFAS design features which would be common to all four licensees' plant specific designs. The intent of the staff comments was to reflect the view that the general design features of the DEFAS concept presented by the CEOG was consistent with the intent of the ATWS rule. It was clearly noted by the staff, however, that staff acceptance of the DEFAS design was contingent on a review of the plant specific submitt61s.

A surr.ary of the staff's cements on the information presented at the two meetings citec above is presenteo below. Enclosure 2 is a copy of the slides presented by the CEOG cn July 12, ISE9.

EtaffCommentsontheCEOGCEFASDesichFeatures The following is the staff's understarcing of the biverse Emergency Fecowater Actuation Systec (LEFAS) as presented in the meetings held on Fay I eno July 12, 1989. The DEFAS consists of sensors, signal ccnditiening, trip recognition, coir.cidence logic, initittion logic, and other circuitry and equipment needed te reonitor plant conditions and inittete emergency feecwater actuaticn curing conditions indicative of an ATWS. The purpose of the DEFAS is to miticete ATWS event consequences by provioing i. diverse means to initiate emergency feeowatcr, thereby minimizing the potential for a comon mode failure affecting both the reacter trip systens and the existing emergency feedwater actuatich system.

The bEFAS initittion signals cause actuation of the auxilitry/ emergency fecowater pumps ar.d valves only if there is a demand for texiliary/wergency feecketer actuction systen (Eft.5) signti and this signal has nct teen generated by the plant protection system (FPS). The occurrence of the EFAS actuation sight) by the PPS, concurrent with the cbsence of an enable from the diverse scram system (DSS), indicates that an ATWS condition does not exist and that enierger.cy feedwcter actuation by the DEFAS is not necessary. Under these conditions, the DEFAS actuation will be blocked through logic in the auxiliary relay cetinet.

The staff's understanding of the functional requirements for the LEFAS is that:

- DEFAS must initiate emergency feedwater flow for conditions indicative of an A1WS where the EFAS has failed.

- The DEFAS will not be required to provide mitigation of an accident such as isolating feedwater ficy to a rupturco steam ger.erator.

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. 'Jqhn N.-Hannon ' ,

DEFAS will stop feedwater flow to the affected steam generator after reaching a pre-determined level setpoint at about 30 minutes after actuation; thereafter, manual operator intervention will control the system.

DEFAS will utilize logic and redundancy to.a'chieve a 2-out-of-2 initiation, as a minimum.

DEFAS will. utilize steam generator water level as the parameter indicative of the need for EFAS actuatien.

- DEFAS will interface with the actuated components via the existing auxiliary relay cabinet (ARC) relays. These relays are not used in the reactor trip system.

DEFAS will be blocked by the EFAS to prevent control / safety interactions and to disable DEFAS when the EFAS actuates.

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' DEFAS will be blocked by the main steam isolation system (MSIS) signal i to prevent control / safety interactions and to disable the DEFAS when L

conditions for MSIS exist.

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DEFAS will be enabled by a signal from the DSS indicating DSS actuation.

DEFAS will' include capabilities to allow testing at power.

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DEFAS will include features that provide alarms., plant computer data and other operator interfaces to indicate system status and meet operability requirements.

DEFAS setpoints will be coordinated with the existing PPS setpoints so that a competing condition between the PPS and DEFAS will be prevented.

1 DEFAS will be interfaced with existing sensors and output devices by a

{ fiber optic (F.O.) technique which has been approved by the NRC for L nuclear plant safety related system application. The DEFAS is fiber optically isolated via qualified devices and physically and electrically separated from the existing PPS. It coes not degrade the existing separation criteria of the PPS.

DEFAS logic will use two microprocessor based programable logic i controllers (PLC). Each licensee will perform software verification ,

I-and validation (Y&Y). The record of the V&V process will be available for staff audit during the post-imp _ lamentation inspection.

DEFAS equipment will be qualified for anticipated operational occurrences.

I DEFAS will be des'igned under the suitable Quality Assurance procedures consistent with the requirements and clarification of 10 CFR 50.62 s contained in Generic Letter 85-06.

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, ' John N. Hannon' DEFAS logic-power will be separate and independent from the existing PPS pcwer. Each DEFAS logic puwer supply is capable of providing 120 VAC uninterruptable' power for up to one hour following the loss of its power bus.

DEFAS will use a single-board computer with ' solid state I/O modules as contrasted with the PPS which uses analog bistable trip units.

Therefore, the DEFAS logic is diverse from the PPS.

i Based on the review of information docketed on April 30, 1989 and the meeting  !

presentations on May I and July 12, 1989, the staff comented that the proposed CE0G cesign for a diverse emergency feedwater actuation system is in general agreement with the ATWS rule and guidance published in Federal Register Vol.

49, No.124, dated June 26, 1984. However, since there may be differences in hardware equipment between the'various plants, staff acceptance of the DEFAS portion of the /TWS implementation for-the affected plants can only be made after receipt of the plant specific designs.

During the meeting, the following technical issues were discussed; the staff positions were stated for each issue.

(1) The interlock from the DSS allows the DEFAS to initiate feedwater flow only if a DSS sctuation has occurreo.

The staff expressed its concern whether the timing of the DSS actuation is sufficient to allow the actuation of emergency feedwater to perform its mitigation function. The CE0G provided an analysis demonstrating the effect of DEFAS timing on peak pressure. The typical difference in time between the reactor system pressure reaching the RTS setpoint and reaching the DSS setpoint is about 8 seconds. The tiniing of DEFAS actu6 tion has a negligible effect on the peak reactor vessel pressure for the limiting ATWS event. Accordingly, the staff comented that the design basis of the 055 for interlocking the DEFAS initiation would be appropriate.

(2) Power sources common for final actuation oevice between tne existing RTS

&nd the DEFAS.

I It is the staff's understanding that the DEFAS cabinet circuitry uses )

independent power sources which are backed up by batteries for up to one l hour. The DEFAS inputs to the auxiliary relay cabinet are thropsh qualified isolators. A fault at the DEFAS cabinet will not propagate to the auxiliary relay cabinets. The staff commented that this is consistent with the intent {

of the ATW5 rule. iiowever, because some components located in the auxiliary j relay cat.inets will be shared for both EFAS and DEFAS and hence share RPS t power, it is the staff's position that each individual licensee should I provide an analysis to demonstrate that power supply faulM (e.g. overvoltage endundervoltgeconditions,degradedfrequencies,andoverturrent}willnot compromise the RTS, the EFAS or the DEFAS equipnient. This analysis should J i

include consideration of alarms for early detection of degraded voltage and j frequency conditions to allow for operator corrective action while the {

affected circuits / components are still capable of performing their interded {

functions. This will be reviewed on a plant specific basis. i i

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- Johr. N. Hannon , .

(S) Operator sctions The DEFAS will secure feeding the affected steam generator after reaching a pre-determined level setpoint (abcut 30 minutes after actuation);

thereafter, manual operator intervention will control the system. The staff commented that an operator action after 30 minutes from automatic actuation is consistent with staff policy.

(4) Separation from existing system The DEFAS final actuation devices are common to existing emergency feedwater system. The ATWS rule guidance states that the implementation must be such that separation criteria applied to the existing protection system are not violated. The DEFAS.will >se qualified F.O. 1solators for interfacing with the existing EFAS. The separation criteria applied to the existing protection system will not be violated. The staff connented thbt this is consistent with the intent of the ATWS rule.

(5) Assumption on centrol system failure impact to the accident analysis.

The CEOG presented justification to show that the DEFAS design will have minimal impact on the accident analysis. With the DSS, ESAS, ano MSIS interlocks, the Owners Group inoicated that a single failure would not cause thc DEFAS to erroneously actuate such that it could adversely impact FSAR Chapter 6 ard 15 event analysis. The staff acknowledged that the Standard Review plan required a consideration of the effects of control systuu action and inaction when assessing the transient respense of the plant. The staff agreed that the conceptual design propcsed by the CEOG acequately minimized the potential fer improper actuation of the DEFAS during non-ATWS accident conditions.

In the course of the meeting, the CEOG asked the staff to consider reviewing a set of assumpticos which would be used in performing plant specific 10 CFR 50.59 analyses of modifications to be nade when installing the ATWS hardware. The staff responded that preparation of an analysis >ursuant tc a 10 CFR 50.59 licensee review was the sole responsibility of eac1 licensee and that the staff would neither do a prior review nor consider approving any such analysis. However, the staff stated that it would review the pertinent aspects of a design and analysis submitted in compliance with 10 CFR 50.62 (the ATWS rule). In this regard, the staff indicated that its comments, as documented above, on the information submitted at the meeting on Hoy 1, 1989, and at this meeting, reflects its view that the proposed DEFAS design is in general agreement with the intent of the ATWS rule. The staff also emphasized that the four licensees should proceed with all aspects of the plant specific designs and analyses.

With regard to implementation of the DEFAS portion of the ATWS cesign, the staff stated its position that the licensees in attendance should proceed in an expedited manter to design, procure and install the hardware for the DEFAS. While the staff will review each of the CEOG plant specific ATWS I

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- John N. Hannon

• dcsigns and issue an SER for each submittal, the staff also stated that design, procurement and implen.entation by the licensees of the DEFAS portion of ATWS should not be delayed pending issuance of these SERs. The staff noted that 10 CFR 50.62(d) required each licensee to " develop and submit a proposed schedule (for implementation)...Each shall include an explanation of the schedule along with a justification if the schedule calls for final implementation later than the second refueling outage after July 26, 1984..."

As done in prior reviews of other ATWS submittals, the staff again stated its position that delays attributable to disagreements over minor technical points is not sutficient basis for a schedular exemption request pursuant to 10 CFR 50.62(d). This position derives from the staff's comments on the CEOG's ATWS discussions on May 1 and July 12, 1989, as documented above, thereby clarifying the major technical issues. In this regard, the staff promised a relatively quick review of plant specific ATWS submittals in recognition of the differences in plant hardware between each of the affected CE plants.

7f"0/

H. David Lynch, Senior Project Engineer Project Directorate III-3 Division of Reactor Projects - III, IV, V and Special Projects

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ENCLOSURE 1

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LIST OF ATTENDEES JULY 12, 1989 NRC LP&L H. D. Lynch D. W. Gamble D. Wigginton R. W. Prados T. Carnes M. Meisner V. Thomas J. Mauck A. Thtdani H. Li S. Newberry SCE C. Poslusny.

W.: Hodges I..Katter.

L. Tran D. Mercurio J..Werniel J. Redmon.

L. Hickman C. Diamond-J. Hannon A. ~ I,' clan (EG&G)

ACRS CE S.'Lcng 11. Ryan J. Ktrinos NUS AF&L H. Cheok M. W. Tull R. A. Barnes APS.

K. L. McCandless Clark

C,elosort 2.

PRESENTATION ON THE RESPONSE TO THE NRC REQUEST FOR ADDITIONAL INFORMATION ON CE NPSD-384 DESIGN FOR.A DIVERSE EMERGENCY FEEDWATER ACTUATION SYSTEM CONSISTENT WITH 10CFR50.62 GUIDELINES ARIZONA PUBLIC SERVICE COMPANY ARKANSAS POWER AND LIGHT COMPANY LOUISIANA POWER AND LIGHT COMPANY SOUTHERN CALIFORNIA EDISON COMPANY JULY 12, 1989 i

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l PRESENTATION OUTLINE O STATEMENT OF INFORMATION REQUEST i

0 RESPONSE TO QUESTION O DISCUSSION O REQUESTED NRC POSITIONS l

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1 QUESTION 1 PROVIDE AN ANALYSIS FOR AN ATWS TO ILLUSTRATE THAT THE TIMING OF THE DSS ACTUATION IS SUFFI-f CIENT TO ALLOW THE ACTUATION OF EMERGENCY i

FEEDWATER FOR MITIGATION

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RESPONSE

CENPD-158, REVISION 1 CONCLUDES THAT AUX. FEED.

DELIVERY HAS NO IMPACT ON THE LIMITING EVENT OR THE PEAK RCS PRESSURE CENPD-263 CONCLUDES THAT THE TIMING OF AUX.

FEED. DELIVERY HAS A SMALL IMPACT ON THE LIMITING ATWS EVENT SUBSEQUENT ANALYSES PERFORMED TO DETERMINE THE SENSITIVITY OF DEFAS TIMING ON PEAK PRESSURE SHOWS NEGLIGIBLE EFFECT ON PEAK PRESSURE FOR LIMITING ATWS EVENT 3

L.... '.

SEQUENCE OF EVENTS LOFW ATWS WITH DSS BUT NO TRIP 3410 MWT CLASS TIME (SEC) EVENT 0.0 LOSS OF ALL NORMAL FEEDWATER 37.6 LOW SG LEVEL AUXILIARY FEEDWATER ACTUATION SIGNAL 62.0 DSS SETPOINT REACHED 86.6 MAXIMUM RCS PRESSURE 90.3 AUX. FEED. DELIVERED FOR SONGS 2

&3 91.6 AUX. FEED DELIVERED FOR WSES-3 114.7 DEFAS INITIATED FLOW DELIVERED SONGS 2&3 116.0 DEFAS INITIATED FLOW DELIVERED FOR WSES-3 116.6 AUX. FEED DELIVER,ED FOR WSES-3 135.0 AUX. FEED. DELIVERED FOR ANO-2 159.4 DEFAS INITIATED FLOW DELIVERED FOR ANO-2 l

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O O 6 SEQUENCE 0F EVENTS LOFW ATWS WITH DSS BUT NO TRIP 3800 MWT CLASS TIME (SEC) EVENT 0.0 LOSS OF ALL NORMAL FEEDWATER 22.8 LOW SG LEVEL AUXILIARY FEEDWATER ACTUATION SIGNAL 32.0 DSS SETPOINT REACHED 68.8 AUX. FEED DELIVERED

78. V VG T45 82.0 MAXIMUM RCS PRESSURE 5 t

AUXILIARY FEEDWATER TIMING SENSITIVITY ASSUMED PLANT Cl. ASS LLSG SIG. AFW DELIVERY PEAK PRESSURE (SEC) (SEC) (PSIA) 3410 MWT 38 58* 4250 3410 MWT 38 ** 4290 3800 MWT 23 33* 3800 3800 MWT 23 ** 3820

• NOT A.CHIEVABLE. FOR DEMONSTRATION PURPOSES ONLY.

• • AUXILIARY FEEDWATER INITIATED AFTER THE TIME OF PEAK PRESSURE 6

4 DESTION 2 PROVIDE A DISCUSSION OF SGLL AS AN ALTERNATIVE TO THE DSS INTERLOCK REAL ISSUE WILL EARLIER AUX. FEED ACTUATION MITIGATE AN I ATWS EVENT FOR LATER TIMES IN THE CYCLE RESPONSE l FOR LIMIT.ING ATWS SCENARIO, AUX. FEED TIMING HAS LITTLE IMPACT ON PEAK PRESSURE FOR THE 3410 MWT CLASS THERE IS NO TIME IN THE CYCLE WHICH YIELDS ATWS PEAK PRESSURES BELOW LEVEL C STRESS LIMITS (CENPD-263)

FOR THE 3800 MWr CLASS THERE MAY BE A SMALL IMPACT ON PEAK PRESSURE FOR LATER TIMES IN CORE CYCLE, I.E., BELOW LEVEL C STRESS LIMITS (CENPD-263) 7 m_____.________..___________.__________. _

3410 Mir PLANT CLASS LOFW ATWS PEAK PRESSURE VERSUS H0DERATOR TEMPERATURE 5000 .

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4500 -

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% MTC9$0%CYCLELIFE-N RCS PRESSURE E

4000 PZR PRESSURE -

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5ll FLANGE LEAKAGE g 3500 -

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$ 3000 LEVEL C STRESS LIMIT 2500 ' '

O -1. 0 -2.0 , -3.0 H0DERATOR TEMPERATURE COEFFICIENT, 10-4 DRH0/F 8

. 3800 MWr PLANT CLASS v.

LOFW ATWS

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PEAK PRESSURE VERSUS H0DERATOR TEMPERATURE COEFFICIENT 5000 4500 - -

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5 4000 -

12 g FLANGE LEAKAGE  ;

5ll3500- N i 0 '

[MTC050%CYCLELI 1 E RCS , PRESSURE

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$ , ' Q LEVEL C STRESS LIMIT,

n. 3000 _

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PZR PRESSURE -

.g l 2500 I

-0.5 . 0 -1. 5 -2.0 -2.5 ,

-3.0 H0DERATOR TEMPERATURE COEFFICIENT, 10-4 DRH0/F 1

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OVESTION 3 TESTING CAPABILITIES l

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RESPONSE

TEST PROCEDURES WILL BE DETERMINED ONCE THE FINAL DESIGN IS ESTABLISHED ON A PLANT SPECIFIC BASIS a

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QUESTION 4

,. V&V PROGRAM FOR PROGRAlHABLE LOGIC CONTROLLERS

RESPONSE

WSES DESIGN DOES'NOT USE PLCs V&V PROGRAM WILL BE ESTABLISHED ON A PLANT SPECIFIC BASIS AT AN APPROPRIATE LEVEL FOR NON-SAFETY SYSTEMS i

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QUESTION 5 CURRENT PLANS AND PROCEDURES FOR AMSAC (DEFAS)

INOPERABLE

RESPONSE

PLANS UNDER CONSIDERATION:

0 IF FEASIBLE, REPAIR AT POWER ON A SCHEDULE CONSISTENT WITH SAFETY SIGNIFICANCE 0 IF NOT FEASIBLE, REPAIR AND PLACE IN SERVICE UPON ENTERING MODE 1 AFTER NEXT REFUELING OUTAGE O IF NOT REPAIRABLE DURING THE OUTAGE, DETERMINE LONG-TERM CORRECTIVE ACTIONS l

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, c QUESTION 6 ASSUMPTIONS REGARDING CONTROL SYSTEM FAILURES AND IMPACT ON 10CFR50.59 NEGATIVE FINDING FOR INSTALLATION

RESPONSE

IMPACT ON CHAPTER 15 EVENTS 0 C0fEON MODE FAILURE POSTULATED BY ATWS RULE NOT ASSUMED 0 A SINGLE FAILURE WILL NOT CAUSE THE DEFAS TO ADVERSELY IMPACT CHAPTER 6 AND 15 EVENTS 1

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REQUEST FOR NRC POSITIONS i 0 CE NPSD-384, SECTION 5 CONCERNS:

APPLICATION OF 10CFR50.59 VERSUS SRP SECTION 7.7 POWER SOURCES C0l440M FOR FINAL ,

ACTUATION DEVICE BETWEEN EXISTING RTS i AND DEFAS  !

SEPARATION FROM EXISTING SYSTEM -

DEFAS FINAL ACTUATION DEVICE IS C0l440N TO EXISTING AUX. FEED SYSTEM OPERATOR ACTION REQUIRED AFTER DEFAS HIGH SG LEVEL SETPOINT REACHED 0 DOCUMENTED NRC POSITIONS TO FACILITATE DESIGN AND IMPLEMENTATION 14

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