ML20044B221

Forwards Addl Info Clarifying Certain Conclusions & Recommendation in SER Re First 10-yr Interval Inservice Insp Program

ML20044B221
Person / Time
Site:	Sequoyah
Issue date:	07/12/1990
From:	Wallace E TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9007180150
Download: ML20044B221 (4)

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TENNESSEE ' VALLEY' AUTHORIT CH ATTANoooA. TENNESSIE 374o1 -

SN 157B' Lookout Place m JUL 121990 )

i U' S.: Nuclear Regulatory Commission-

' ATTN:: Document Control Desk Washington _D.C. _20555 l

. Gentlemen:- ,l s -In the Matter of ) Docket Nos. 50-327 Tennessee Valley Authority ) 50-328 SEQUOYAH; NUCLEAR-PLANT (SQN) UNIT 2 - NRC SAFETY EVALUATION REPORT (SER) FOR 7

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THE FIRST-10-YEAR INTERVAL IN-SERVICE INSPECTION (ISI) PROGRAM

References:

-- 1.- NRC letter to TVA' dated hpril 19, 1990, "First 10-Year

' -Interval Inservice Inspection Program (TAC 59458) - Sequoyah Nuclear Plant, Unit 2"-

2. TVA letter'to NRC dated June 12, 1989, "Sequoyah Nuclear Plant (SQN) - Revised In-Service Inspection _(ISI) Program for Unit 2 (Revision 14)"

By Reference 1 NRC submitted to TVA the SER for the-SQN ISI program on s Unit 2.. LTVA: has completed its review of the subject SER and has, identified

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several'areasithat-. require clarification. These areas were discussed during aniinformal meeting at'SQN on May 22, 1990, between NRC and TVA. As agreed in the meeting.:TVA is providing_ additional information to clarify.certain conclusions and recommendations contained in the Unit 2 SER. -

Enclosed is the additional'information for the SQN Unit 2 ISI program. The-enclosed'information is also applicable to Unit 1.

No comitments are contained . in this submittal. Please direct questions 3 concerningEthis issue to Don V. Goodin at (615) 843-7734  !

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L Very truly yours, i o

. TENNESSEE VALLEY AUTHORITY

' //de E. G. Wallace, Manager p Nuclear Licensing and

, Regulatory Affairs 1

j. Enclosure L cc: See page 2 /

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. 9007180150 900712 I h

PDR ADOCK 05000327 H Q PDC  !

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An Equal Opportunity Employer

> U.S. Nuclear Regulatory Commission k--1 $ M cc (Enclosure): .

LMs._S. C. Black, Deputy Director Project Directorate II-4 U.S.' Nuclear, Regulatory Commission One White-Flint, North 11555 Rockville Pike Rockville, Maryland -20852

' Jack'N. Donohew U.S. Nuclear Regulatory Comnission s

One White Flint, North

.11555 Rockv111e Pike Rockville, Maryland 20852 NRC Resident Inspector-Sequoyah Nuclear Plant 2600 Igou Ferry-Road

Soddy Daisy, Tennessee 373??

Mr.' B. A. Wilson, Project Chief U.S.' Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323

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arb ENCLOSURE-i

1. Relief Request In-Service Inspection (ISI) -6. Steam Generator Nozzle Inside Radius Section, Category B-D, Item B3.140 (page 14 of the. Technical Evaluation Report :(TER) enclosed in NRC's letter to TVA dated LApril' 19, 1990, "First 10-Year. Interval Inservice Inspection Program

[ TAC 59458] - Sequoyah Nuclear Plant, Unit 2")

Item (a) under conclusions and recommendations states ". . . the licensee should visually inspect'the nozzle inner radii if it is necessary to enter the steam generator inlet and outlet plenums for maintenance or other 1 inspection activities."

It is questionable if a visual inspection could provide meaningful results. Additionally, individual " stay-time" in the primary chamber would be limited based on the high radiation dose rate associated with the'

. primary chamber, generally,. on the order of 30 rem /hr. Steam generator

" jumpers" enter or approach the primary chamber only when necessary and-

, -exit'the area as soon as possible. Due to these high dose rates, the actual inspection time would be severely limited.

Visual and surface examinations were addressed by the TER in the f= evaluation of Relief Request ISI-6. It was stated in the evaluation that 1

performance of a visual.or surface examination would result in high

radiation dosages with no assurance of a meaningful; examination. 4 TVA, therefore, requests that the proposed alternative examination of Relief Request:ISI-6 be granted without the augmented visual inspection.

' 2E Relief' Request ISI-3, Pressure-Retaining Dissimilar Metal Welds! in Piping 1 Category B-F, Item B5.50 2and Category'B-J. Items 4.5_, 4.6, and 4.7 (pages

p 17 and 21 of'the TER)' 1 It was' identified in the'SER/TER that NRC's evaluation of SQN's Unit 2 10-year ISI~ program was based on Revision 13~. The Unit 2 ISI program was-subsequently revised (Revision 14) and' submitted to NRC by letter dated

' June 12, 1989. . Revision.14 added nine additional Category B-F welds and (

nine additional Category B-J piping welds to Relief Request ISI-3.

Additional NRC review will be required.

,3. Relief Request ISI-8. Pressure-Retaining Welds on Pump Casings t ,

Category B-L-1,' Item B12.10 (page 24 of the TER)

. Item (c) under conclusions and recommendations states ". . , periodic 3-'

-inserv. ice testing of the pumps is conducted in accordance with IWP."

Based on discussions with NRC staff, TVA understands this statement to require testing of the pumps in accordance with IWP only if the pumps are included within the scope of IWP and are required to be tested by IWP, rather than testing to IWP as an augmented NRC requirement.

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4 a.

The reactor coolant pumps are'not contained in SQN's IWP test program and therefore are not subject to the tests required by Item (c).

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4. 3elief Request ISI-1. Pump Internal Pressure Boundary Surfacc i Category B-L-2. Item B12.20 (page 26 of TER)

The comments of Item 3 above for Relief Request ISI-8 also apply to this-relief request for Item (d) under. conclusions and recommendations.

5. Relief Request ISI-2, Valve __ Internal- Pressure Boundary burf ace t Category B-M-2, Item B12.40 (page 29 of the TER)

Item (b) under conclusions and recommendations states ". . . periodic inservice testing of the valves is conducted in accordance with IWV . . ." Based on discussions with NRC staff, TVA understands this statement to require testing of the valves ~in accordance with IWV only-if the valves are included within the scope of IWV and are required to be tested-by IWV~, rather than testing to IWV as an augmented NRC-requirement.

Currently, all-valves = listed in Relief Request ISI-2 are contained in SQN's IWV test program. . Based on TVA's understanding of Item (b), a valve would not be required to be added to SQN's IWV testing program solely on

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'the basis that it is subject to Category B-M-2 visual examination.

6. Relief Request ISI-14 Scheduling Requirements of" Tables IWB-2412-1 and IWC-2412-1 for Examination of Class 1 and 2 Piping Welds. Piping Supports, and Major Component Supports (page 43 of the TER)

The sentences under proposed alternative examination state "The percentages' required by Code will not be-met,on the second and-third

< . period of..the first inspection interval. The percentages for the first period will be higher than allowed by Code."

.The' reference to the first period in the.second sentence should read the second . period. TVA considers this to be a typographical error.