ML20237K013

Summary of 870811 Meeting W/Westinghouse & Westinghouse Owners Group Subgroup on Turbine Valve Testing Frequency in Bethesda,Md Re Program on Turbine Valve Testing Frequency. Agenda,List of Attendees & Related Matls Encl

ML20237K013
Person / Time
Issue date:	08/24/1987
From:	Norberg J Office of Nuclear Reactor Regulation
To:	Shao L Office of Nuclear Reactor Regulation
References
NUDOCS 8708270018
Download: ML20237K013 (49)

Text

- - - - _ _ - _ _

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UNITED STATES i

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',h NUCLEAR REGULATORY COMMISSION l

W ASHINGTON, D. C. 20555 p

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4.**

August 24, 1987 MEMORANDUM FOR:

Lawrence C. Shao, Director Division of Engineering & Systems Technology FROM:

James A. Norberg, Special Assistant Division of Engineering & Systems Technology SUBJECT':

SUMMARY

OF AUGUST 11, 1987 MEETING REGARDING PROGRAM ON TURBINE VALVE TESTING FREQUENCY On August 11, 1987, representatives from Westinghouse Electric Corporation and the Westinghouse Owners Group Subgroup on Turbine Valve Testing Frequency I

(WOG TVTF) briefed the staff on their program regarding turbine valve testing frequency. The group intends to submit a topical report on their findings to the NRC for review and approval. A list of attendees is provided in Enclosure 1.

Presentation material used by Westinghouse and WOG TVTF is provided in.

Introduction The program on turbine valve testing frequency is sponsored by a subgroup of the Westinghouse Owners Group, Ken Chapple (IP-3) Chairman.

The group is composed of 11 members including both Westinghouse and non-Westinghouse plants with Westinghouse turbines.

The objective of the program is the determination of justifiable turbine inlet valve testing intervals, the documentation of the justification for submittal to NRC, and the NRC approval of the methodology and application of the methodology to member plants.

Program Scope The program scope includes evaluation and use of nuclear turbine operating data, fault tree evaluation of turbine overspeed, evaluation of turbine missile prob-ability, and application of evaluations to determination of turbine valve test intervals.

It is intended to be applicable to member plants only.

Briefing Content The briefing covered turbine types and valve arrangements, recent valve testing evaluations, and recent incidents.

Data sources were discussed.

Various tur-bine valve arrangements were presented and identified with member plants. The probabilistic analysis methods used to determine the probability of turbine over-speed and missile ejection was discussed. Deterministic and probabilistic methods for determining rotor inspection interval and relevance to the current study was discussed. Suggested acceptance criteria for inspection intervals was presented and compared to turbine missile probabilities calculated for the

__ 'l utility groups currently installed or to be installed turbines.

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i.)p 8708270018 870024 PDR TOPRP ENVWEST C

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LLicensing, issues'were'briefly discussed with the general conclusion'that the;

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topical report will be submitted using the lead plant approach.- Lead plant.can-1

'didates were given.as'.Diablo Canyon, Salem, and Prairie Island..

J Odesnnistercara.,

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-James A'. Norberg, Special Assistant j

j.

Division of Engineering & Systems' Technology

Enclosures:

As stated o t.

.cc:

T. Dunning s

W. LeFaye E.' Chow

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, ';r Distribution (w/encls.)

b tral fi h PDR DEST R/F J.- Norberg l

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. Enclosure 1 List of Attendee _s NRC/WOG TVTF Subgroup Meeting Turbine Valve Test Frequency Evaluation August 11, 1987 NRC WOG TVTF Subgroup Westinghouse i

J. Norberg K. Chapple, NYPA R. Jansen T. Dunning J. Lomm, NYPA J. Martin W. LeFave P. Kokolakis, NYPA R. Rodibaugh E. Chow M. Schoppman, FP&L D. Sharp

-D. Neighbors J. H'nds, PG&E D. Berrong R. Swartywelder, PWE&G D. Campbell T. Thomas, NSP G. Hyde-R. Meyer, NSP K. Daschke J. Stafford, CPC J. Lewis, CPC D. Schoan, WEPC 4

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MEETING OF THE TURBINE VALVE TEST FREQUENCY EVALUA110N SUBGROljP WITH THE NRC 1

BETHESDA AUGUST 11, 1987 i

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l AGENDA INTRODUCTION TURBINE TYPES AND VALVE ARRANGEMENTS DATA FAULT TREE EVALUATION AND RESULTS LICENSING ISSUES OPEN DISCUSSION i

CLOSE l

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9' INTRODUCTION.

PROGRAM SPONSORSHIP

' PROGRAM SPONSORED BY SUBGROUP OF WESTINGHOUSE OWNERS GROUP, KEN CHAPPLE (INDI AN POINT 3) CHAIRMAN COMPOSED OF 11 MEMBERS INCLUDING BOTH WESTINGHOUSE AND NON-WESTINGHOUSE PLANTS WITH WESTINGHOUSE TURBINES PROGRAM OBJECTIVE.

DETERMINATION OF-JUSTIFI ABLE TURBINE INLET VALVE TEST INTERVAL s I

DOCUMENTATION OF JUSTIFICATION FOR SUBMITTAL TO NRC

[

.NRC APPROVAL OF METHODOLOGY AND APPLICATION OF METHODOLOGY TO MEMBER PLANTS PROGRAM SCOPE EVALUATION AND USE OF NUCLEAR TURBINE OPERATING DATA I

FAULT TREE EVALUATION OF TURBINE OVERSPEED I

EVALUATION OF TURDINE MISSILE PRDGABILITY i

APPL ICATION OF EVALUATIONS TO DETERMINATION OF T(IRBINE VALVF TEST I

INTERVAL PROGRAM APPLICABILITY j

APPLICABLE TO MEMBER PLANTS ONLY i

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DIABLO CANYON'1 & 2 H.B.' ROBINSON INDIAN POINT 2 & 3 L

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a RECENT VALVE TESTING EVALUATIONS L

WCAP STUDY - ALABAMA POWER - FARLEY GENERIC RECOMMENDATION (W) GTSD RECOMMENDS MONTHLY TESTING OF THE STEAM ADMISSION VALVES OF NUCLEAR TURBINE-GENERATORS WITH STEAM CHESTS I

BASIS FOR RECOMMENDATION:

i o

DEMONSTRATED ABILITY TO PREVENT OVERSPEED WITH VARIED TESTING FREQUENCIES l

o NO SIGNIFICANT DIFFERENCE IN VALVE RELIABILITY BETWEEN THOSE TESTED WEEKLY AND THOSE TESTED MONTHLY l

o JUDGED TO BE A PRUDENT EXTENSION l

OF PREVIOUS RECOMMENDATION l

f WOG - TVTF STUDY FOR 1 ON 1 8 1 ON 2 TYPES l

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FIELD INCIDENTS REPORT o

OUTAGE DATA SYSTEM - STEAM TURBINE-GENERATOR AVAILABILITY REPORT SYSTEM l

o GTSD DATA BANK o

SURVEY OF GTSD ENGINEERS AND MANAGERS INVOLVED I

WITH VALVES i

o 1982 & 1986 SURVEYS OF OWNERS OF OPERATING (W) NUCLEAR TURBINES j

1

'1 JAM 3/IV' a-t'

1986 NUCLEAR UNIT SURVEY 49 INQUIRIES 31 RESPONSES INLET VALVE TYPES 1 ON 1 STEAM 1 ON 2 CHEST 7

TESTED WEEKLY 4

3 19 TESTED MONTHLY 13 6

5 TESTED "0THER" 1

4 RECOMMENDED FREQUENCY WEEKLY MONTHLY 5

RELEVANT VALVE INCIDENTS IDENTIFIED DURING TEST l

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GENERATION TECHNOLOGY SYSTEMS DIVISION SUPPORT OF THE PROBABILITY STUDY:

o CONTROL AND TRIP SYSTEM DESCRIPTION o.

VALVE SYSTEM DESCRIPTION o

FAULT TREES o

SERVICE HOURS o

MALFUNCTIONS o

LP ROTOR INSPECTION - PROBABILISTIC &

DETERMINISTIC DATA o

WCAP REVIEW l

J JAM 5/IV 1

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l CLASSIFICATION OF TURBINES BY VARIATION NUMBER 1

2 3

4 5

6 Variation Turbine Description of Description of Control Trip Numbcr Type H P Valving L P Valving System System 1

BB-95,96 1-on-2 SV-CV 1-on-1 RS-IV 300 PSI 1

2 BB-95,96 1-on-1 SV-CV 6-DV 300 PSI 1

Steam Dump 3

BB-95,96 1-on-1 SV-CV 1-on-1 RS-IV AEH-DEH 2

BB-296 4

BB-95,96 1-on-2 SV-CV 1-on-1 RS-IV AEH-DEH 2

6 BB-95,96 1-on-2 SV-CV 4-DV AEH-DEH 2

Steam Dump 7

BB-296 2TV-2GV 1-on-1 RS-IV AEH-DEH 2

Steam Chest 8

BB-296 2TV-2GV 1-on-1 Rs-IV AEH-DEH 3

Steam Chest l

CLASSIFICATION OF TURBINES:

Variation l

Station Number Turkey Point 3 & 4 1

Indian Point 2 2

Indian Point 3 2

i Diablo Canyon 1 & 2 3

Salem 1 & 2 3

Maine Yankee 3

Palisades 3

Prairie Island 1 & 2 4

Kewaunee 4

Robinson 2 4

Point Beach 1 & 2 6

St. Lucia 1 & 2 7

Shearon Harris 8

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GENERAL ARRANGEMENT OF TURBINE VALVES FOR VARIATION 2 (INDIAN PDINT UNITS 2 & 3) i i

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j GENERAL ARRANGEMENT OF TURBINE VALVES FDR VARIATIDN 4 l

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GENERAL ARRANGEMENT OF TURBINE VALVES FDR VARIATIONS 7 & 8 (VARIATIDN 7 - ST. LUCIE VARIATION 8 - SHEARON HARRIS) i i

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ANALYSIS OF TURBINE OVERSPEED AND MISSILE EJECITON 4

FAULT TREES OVERSPEED PROBABILITIES MISSILE EJECTION PROBABILITIES EFFECTS OF TURBINE VALVE TEST INTERVAL AUGUST 11, 1987 l

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RESULTS OF PHASE 1 STUDY (MARCH-JUNE, 1986) o 3-MONTH TURBINE VALVE TEST INTERVAL WAS FEASIBLE o

PHOSPHATE FEEDWATER CHEMISTRY

• RESULTED IN FOUR F0LD INCREASE IN PROBABILITY OF. DESTRUCTIVE OVERSPEED..

• UNACCEPTABLE!

o BB95 WITH MECHANICAL-HYDRAULIC CONTROL SYSTEM HAD

)

PROBABILITY OF DESTRUCTIVE OVERSPEED THAT WAS IN SAME BALL PARK AS BB296 STEAM CHEST DESIGN.

P(C) = 3.6 x 10-6 PER YEAR (3-MONTH) l

GOALS OF CURRENT PROBABILISTIC STUDY (0CTOBER 1986 - JULY 1987) o PROVIDE A PROBABILISTIC ANAYSIS (OR ANALYSES) 0F TURBINE MISSILE EJECTION.THAT INCORPORATES THE EFFECTS OF EXTENDING THE TURBINE VALVE TEST INTERVAL TO MAXIMUM OF 12 MONTHS.

SPECIFIC (RATHER THAN GENERIC)

COMPREHENSIVE CONSERVATIVE o

DOCUMENT THE RESULTS IN A REPORT SUITABLE FOR SUBMITTAL TO THE NRC.

THIS REPORT SHOULD PROVIDE PLANT-SPECIFIC MISSILE EJECTION PROBABILITIES AND SHOULD SERVE AS THE PROBABILISTIC BASIS THAT SUPPORTS ALL OF THE OWNER'S REQUESTS FOR EXTENSIONS OF THE TURBINE VALVE TEST INTERVAL.

4 l

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STEPS IN PROBABILISTIC ANALYSIS (0VERVIEW) e

4. QUANTIFY THE PROBABILITY OF TURBINE MISSILE l

EJECTION (P )

1 i

i

3. QUANTIFY THE PROBABILITY OF TURBINE OVERSPEED

[P(A), P(B), P(C)]

2.

DEVELOP BASIC FAULT TREE FAILURE DATA AND APPLY TO FAULT TREES I

J 1.

CONSTRUCT FAULT TREES 1

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TERMIN0 LOGY

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MISSILE EJECTION

' SYSTEM SEPARATION t

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1 VALVE SERV 0-ACTUATOR

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r DEVELOPMENT OF OVERSPEED FAULT TREES I. EVALUATE SYSTEMS AND IDENTIFY SIGNIFICANT CAUSES OF OVERSPEED RESULTS:

TWO SYSTEMS CAN CAUSE OVERSPEED:

o TURBINE VALVE AND CONTROL SYSTEM o

EXTRACTION NONRETURN VALVE SYSTEM II. GROUP TURBINES OF THE SUBGROUP BY COMMON CHARACTERISTICS RESULTS:

o EACH TURBINE WAS ASSIGNED TO ONE OF SEVEN VARIATION CATEGORIES III. DEFINE THE SEQUENCES OF FAILURES LEADING TO ONE OF THREE OVERSPEED EVENTS:

(DESIGN, INTERMEDIATE, 1

DESTRUCTIVE)

IV. CONSTRUCT BOUNDING FAULT TREES FOR EACH VARIATION CATEGORY AND FOR EACH OVERSPEED EVENT DATA USED:

- GENERIC AND PLANT-SPECIFIC INFORMATION ON TURBINE VALVES AND CONTROLS

- PREVIOUS STUDIES, I.E. W 1974, 1982, 1984, 1986

6 EXAMPLE OF UPPER LEVELS OF DESTRUCTIVE OVERSPEED FAULT TREE kRSN$E!LITYOF 85iPSWill"'

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J hAfbskbhL8SE 10 FAILS TO CLOSE

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0008 0009 MECHA

'AL FAIL, AUTOSTOP OIL NOT MECHANICAL FAIL.

HIGH PRESSURE 8lM58L 85 ofain 85 R8'#4?ba" ouE?OCln?W8f" 85 f.

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hAULTS OR ORAIN FAULTS

'0010 0011 0012 0013

7 4

BASIC TURBINE VALVE FAULTS o

VALVE STICKING

- STOP (THROTTLE) VALVES

- CONTROL (G0VERNOR) VALVES

- REHEAT STOP VALVES

- INTERCEPT 0R VALVES o

SERV 0 MOTOR (SERV 0-ACTUATOR) FAULTS

- PISTON STICKS OPEN

- DRAIN LINE IS CLOGGED

- DRAIN LINE FROM TOP 0F PISTON IS CLOGGED (AEH-DEH)

- RELAY SYSTEM FAILS (300-PSI) o CONTROL (G0VERNOR) SERVO VALVE FAILS TO CONNECT CYLINDER l

TO DRAIN (AEH-DEH) o SERVO VALVE CIRCUITRY FAILS (AEH-DEH) o DUMP VALVE (0N TURBINE VALVE) STICKS CLOSED (AEH-DEH) o STOP VALVE MECHANICAL DAMAGE INHIBITS CLOSING l

/

i PROBABILITY OF TIME-DEPENDENT BASIC FAULTS U = 1/2 A T WHERE A = FAILURE RATE [HR-13 T = MISSION TIME [HR]

U = FAILURE ~ROBABILITY OR UNAVAILABILITY TURBINE VALVE FAULTS :

o FAILED OR NON-FAILED STATE IS VERIFIED BY TESTING o T = TIME INTERVAL BETWEEN TESTS o T = 1-MONTH, 3-MONTHS, 6-MONTHS, 12-MONTHS

/

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3 1

SOURCES OF FAILURE DATA o

WESTINGHOUSE BASIC SERVICE EXPERIENCE l

o OTHER SOURCES :

I IEEE 500 l

MCCORMICK (WASH-1400) j SWAIN & GUTTMAN (NUREG/CR-1278) i

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'/C RESULTS OF FAULT TREE ANALYSIS o

MEAN PROBABILITY OF DESTRUCTIVE OVERSPEED:

3 x 10-8 TO 1 x 10-6 PER YEAR

)

o-MEAN PROBABILITY OF DESIGN OVERSPEED:

3 x 10-4 TO 1 x 10-3 PER YEAR 0.5 PER YEAR o

MEAN PROBABILITY OF INTERMEDIATE OVERSPEED:

5 x 10-7 TO 2 x 10-5 PER YEAR 1 x 10-5 TO 3 x 10-3 PER YEAR o

DOMINANT FAULTS IN DESIGN OVERSPEED (6-MO):

- CONTROL VALVE STICKING

- COMMON CAUSE STICKING OF INTERCEPT 0R VALVES

- COMMON CAUSE STICKING OF EXTRACTION NONRETURN VALVES

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DOMINANT FAULTS IN DESTRUCTIVE OVERSPEED (6-MO):

- STOP AND CONTROL VALVE STICKING PRIMARY DRAIN LINE BLOCKAGE

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u CALCULATION OF TOTAL PROBABILITY y

OF TURBINE MISSILE EJECTION i

BASIC EQUATION:

P(1) = P(A) x P(M/A) + P(B) x P(M/B) + P(C)

WHERE:

P(1) = TOTAL ANNUAL PROBABILITY OF TURBINE MISSILE EJECTION i

P(A) = ANNUAL PROBABILITY OF DESIGN OVERSPEED i

P(B) = ANNUAL PROBABILITY OF INTERMEDIATE OVERSPEED t

P(C) = ANNUAL PROBABILITY OF DESTRUCTIVE OVERSPEED P(M/A), P(M/B) = CONDITIONAL PROBABILITIES OF MISSILE EJECTION GIVEN THE OCCURENCE OF DESIGN AND INTERMEDIATE OVERSPEED, RESPECTIVELY P(M/R) = ANNUAL PROBABILITY OF MISSILE EJECTION AT NORMAL RUNNING SPEED I

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L.P. stoTOR INSPECTION INTERVAL

[ YEARS) j 1

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n METHOD OF DETERMINING ROTOR INSPECTION INTERVAL AND RELEVANCE TO CURRENT STUDY DETERMINISTIC:

- THE TIME THAT IT TAKES FOR A HYPOTHETICAL CRACK IN THE ROTOR TO GROW TO CRITICAL SIZE IS CALCULATED

- HALF OF THE CALCULATED TIME IS USED AS THE LENGTH OF TIME THAT THE ROTOR CAN RUN UNTIL THE NEXT INSPECTION

- FURTHER REDUCTION IN TIME'IS MADE IF INSPECTION INDICATES PRESENCE OF CRACKS I

• CONCLUSION:

PROGRAM PROVIDES HIGH DEGREE OF ASSURANCE j

THAT A MISSILE WILL NOT BE EJECTED AT RUNNING SPEED OR AT SPEEDS UP TO DESIGN OVERSPEED

of METHODS OF DETERMINING-ROTOR INSPECTION (CONTINUED)

PROBABILISTIC:

- PROBABILITIES OF MISSILE EJECTION AT SPEEDS UP TO DESIGN OVERSPEED ARE CALCULATED AS A FUNCTION OF RUNNING TIME OF THE TURBINE

- LENGTH OF TIME TO THE NEXT ROTOR INSPECTION IS MADE BY DECISION BASED ON THE HAGNITUDE OF THE MISSILE EJECTION PROBABILITY CONCLUSION:

PROGRAM ALLOWS FOR AN INFORMED DECISION TO BE MADE ON WHEN TO REINSPECT THE ROTORS l

f

SUMMARY

OF CURRENT RELIABILITY CRITERIA (UNFAVORABLY 0RIENTED TURBINE)(1)

PROBABILITY-

[YR-13 REQUIRED LICENSEE ACTION (A).

P1 < 10-5

THIS IS THE' GENERAL MINIMUM RELIABILITY REQUIREMENT FOR LOADING THE TURBINE AND BRINGING THE SYSTEM ON LINE."

(B) 10-5 < pl <10-4 "IF THIS CONDITION IS REACHED DURING OPERATION, THE TURBINE MAY BE KEPT IN SERVICE j

U'lTIL THE NEXT SCHEDULED OUTAGE, AT WHICH TIME THE H

LICENSEE IS TO TAKE ACTION TO REDUCE P1 TO MEET THE APPROPRIATE A CRITERIA (AB0VE)

BEFORE RETURNING THE TURBIHE TO-SERVICE."

(C) 10-4 < P1 <10-3 "IF THIS CONDITION IS REACHED DURING OPERATION, THE TURBINE IS TO BE ISOLATED FROM THE STEAM SUPPLY WITHIN 60 DAYS,..."

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(1) U.S. NUCLEAR REGULATORY COMMISSION LETTER FROM C. E. ROSSI TO J. A. MARTIN OF WESTINGHOUSE ELECTRIC CORPORATION, DATED FEBRUARY 2, 1987.

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SUGGESTED ACCEPTANCE CRITERIA FOR WOG TVTF SUBGROUP A. TURBINES WITH DETERMINISTIC INSPECTION INTERVALS l

l A.1 P(1) < 5 x 10-6 DURING FIRST QUARTER OF LAST l

YEAR OF OPERATION BEFORE INSPECTION, OR AT ANY TIME PRIOR (CASE 1)

A.2 P(1} < 5 x 10-5 AT END OF LAST YEAR OF OPERATION BEFORE INSPECTION (CASE 2)

'l B. TURBINES WITH PROBABILISTE INSPECTION INTERVALS B.1 - P(1) < 1 x 10-5

CASE 1 B.2 P(1) < 1 x 10-4

CASE 2 EVALUATED BY :

l EQN A:

P(1) = P(A) x P(M/A) + P(B) x P(M/B) + P(C)

)

EQN B:

P(1) =... + P(M/R)

I l

l 1

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c RESULTS OF TURBINE MISSILE ANALYSIS o

P(1) WAS CALCULATED FOR TWENTY-TWO SETS OF LP ROTi)RS o

CALCULATED P(1)'s OF ALL TURBINES CURRENTLY INSTALLED, OR TO BE INSTALLED (NINETEEN SETS OF LP ROTORS) SATISFY THE ACCEPTANCE CRITERIA FOR ALL TURBINE VALVE TEST INTERVALS UP TO AND INCLUDING 12 MONTHS.

o CALCULATED P(1)'s OF TWO SETS OF SPARE LP ROTORS CURRENTLY SATISFY THE ACCEPTANCE CRITERIA AT l

TURBINE VALVE TEST INTERVALS OF 6 MONTHS OR LESS.

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1 ASSUMPTIONS CONTRIBUTING TO CONSERVATISM i

IN ANALYSIS 1.

-DEFINITION OF TURBINE VALVE FAILURE SEQUENCE FOR DESIGN OVERSPEED IS CONSERVATIVE.

2.

DEFINITION OF FAILURE SEQUENCE FOR INTERMEDIATE OVERSPEED~IS CONSERVATIVE

3. -

MALFUNCTION NUMBERS THAT ARE NEAR THE UPPER B0UND OF VALUES FROM WESTINGHOUSE SASIC SERVICE EXPERIENCE HAVE BEEN USED 4.

.ALL TURBINES HAVE BEEN ASSUMED TO BE UNFAVOR&B11 ORIENTED 5.

THE SELECTICH OF THE TURBINE VALVE TEST INTERVAL IS TO BE BASED ON MISSILE PROBABILITIES DURING THE LAST YEAR OF OPERATION BEFORE INSPECTION OF THE LP ROTORS.

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LICENS]NG ISSUES

, REPORT l

RESULTS OF PRDGRAM IN WCAP-11S25 APPLICABLE TO MEMBER PLANTS ONLY CAN BE UPDATED TO BE APPLICABLE TO ADDITIONAL PLANTS.

MAY RE0lJ1RE" SUBMITTAL TO THE NRC BY THAT PLANT.

APPROVED REPORT l

1 WILL BE USED AS BASIS FOR CHANGES TO TECHNICAL SPECIFICATIONS WILL PROVIDE BASIS FOR' DETERMINATION OF TURBINE val.VE TES1 INTERVAL.

CAN BE USED BY MEMBER PLANTS TO ADJUST TURBINE VALVE TEST IN1FRVAl AS NECESSARY TO ACC0tJNT FOR ROTOR CHANGES OR REVISED DATA WITH0llT f

RESUBMITTAL TO OR APPROVAL BY THE NRC DOCKETING WILL BE SUDMITTED ON A LEAD PLANT DOCKET.

LEAD PLANT CANDIDATES ARE i

DIABLO CANYON, SALEM, AND PRAIRIE ISLAND REMAINING MEMBERS WILL SUBM11 SUBSEQUENT TO NRC APPROVAL. OF LFAD PLAN 1 SUBSEQUENT NRC REVIEWS SHOULD BE ABBREVIATED AS A RESUL1 0F THE LEAD PLANT REVIEW.

NRC REVIEW AN NRC SER APPROVING THE TOPICAL AS A REFERENCE FOR FOLLOW-ON SUBMITTALS AND APPROVING THE LEAD PLANT SUBMITTAL IS REQUESTED NRC ISSUANCE OF THE LEAD PLANT SER IS REQUESTED WITHIN 6 MONTHS OF THE LEAD PLANT SUBMITTAL l

IT'IS REQUESTED THAT FOLLOW-ON SERs BE APPROVED WITHIN 90 DAYS OF l

SUBMITTAL I

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