ML20206J707

Forwards Listed Info Re Small Bore Piping & Supports Interim Acceptance Criteria Phase Ii,Per 870303 Meeting.Completes Commitments Made During 870303 Meeting

ML20206J707
Person / Time
Site:	Sequoyah
Issue date:	04/08/1987
From:	Gridley R TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 8704160159
Download: ML20206J707 (24)

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TENNESSEE VALLEY AUTHORITY

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CHATTANOOG/ . TENNESSEE 374o1 SN 157B Lookout Place APR 081987 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 Gentlemen:

In the Matter of. ) Docket Nos. 50-327 Tennessee Valley Authority ) 50-328 SEQUOYAH NUCLEAR PLANT - ALTERNATE ANALYSIS PROGRAM PHASE II Pursuant to our meeting of March 3, 1987, on Sequoyah Small Bore Piping and Supports Interim Acceptance Criteria Phase II, TVA submits the following information:

4 Enclosure A - Sequoyah Nuclear Plant (SQN) Units 1 and 2, Alternate Analysis Review Program, Phase 2 Scope, Approach, and Schedule Enclosure B - Sequoyah Nuclear Plant (SQN) Alternate Analysis Review Program, Justification for Limited Walkdowns for Unit 2, Phase 1 Enclosure C - Sequoyah Nuclear Plant Units 1 and 2 Instrument Lines

-and Supports Issues, Current Activities, and Planned' Post-Restart Activities Enclosure D - Sheet 9 of the March 3, 1987 handout, revised to i incorporate NRC comments Enclosure E - A list of specific commitments made in this submittal

.This submittal completes commitments made during our meeting of March.3, ,

1987. If additional information is required, please telephone 1 M. R. Harding at (615) 870-6422.

Very truly yours, j TENNESSEE VALLEY AUTHORITY z j R. ridleyfirector Nuclear Safety and Licensing Enclosures cc

see page 2 OhhPDR An Equal Opportunity Employer-

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l U.S. Nuclear Regulatory Commission

/ R 081987 cc (Enclosures):

Mr. G. G. Zech, Assistant Director Re51 onal Inspections Division of TVA Projects Office of Special' Projects U.S. Nuclear Regulatory Commission

-Region II 101 Marietta Street, NW, Suite 2900

. Atlanta, Georgia 30323 Sequoyah Resident Inspector Sequoyah Nuclear Plant 2600 18 0u Ferry Road Soddy Daisy, Tennessee 37379 r

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U.S. Nuclear Regulatory Commission.

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L Mr. G. G. Zech,' Assistant Director Regional Inspections Division 'of TVA Projects Office of Special Projects U.S. Nuclear Regulatory Commission Region II

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101 Marietta Street, NW,LSuite 2900 Atlanta, Ceorgia 30323 Sequoyah Resident Inspector 3

Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379-MRH:MJB:WAM:KLH cc (Et closures):

RIMS, MR 4N 72A-C 4 H. L. Abercrombie, O&PS-4, Sequoyah j E. S. Christenbury, E11 B33 C-K l C. H. Crowell, LP 6N 38A-C W. H. Hannum..:BR IN 76B-C M. R. Harding, O&PS-4, Sequoyah T. A. Ippolito, LP 5N 121B-C N. C. Kazanas, LP AN 45A-C J. A. Kirkebo, W12 A12 C-K D. R. Nichols, LP SN 302B-C

! L. M. Nobles, POB-2, Sequoyah R. K. Seiberling, 716C EB-C j M. B. Whitaker, LP 5N 303B-C j D. L. Williams, W10 B85 C-K f

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Enclosure A Sequoy:2h Nuclear Plant (SQN)-

Units 1 and 2 Alternate Analysis Review Program l Phase 2 Scope, Approach, and Schedule i

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CONTENTS i

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l.0 Scope. . . . . . . . . . . . . . . ..... ........... Al 2.0 Approach . . . . . . . . . . . . . ................. A2 2.1 Process Piping. . . . . . . . ................. A2 l 2.2 Instrument Lines. . . . . . . ................. A3 i l

3.0 Schedule . . . . . . . . . . . . . ................. A3

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1.0 Scope (a) Pipe Classes TVA Classes B, C, D, and M (equivalent to ASME III, classes 2 and 3).

(b) Process Piping The following systems include alternately analyzed piping within the scope of this program. The systems are listed in the order of the priority established for performing the Phase 2 walkdowns and evaluations.

Priority Syst_em Description 1 68 Reactor Coolant 2 3 Main and Auxiliary Feedwater 3 62 Chemical and Volume Control 4 63 Safety Injection 5 74 Residual Heat Removal 6 87 Upper Head Injection 7 61 Ice Condenser 8 72 Containment Spray 9 70 Component Cooling 10 67 Essential Raw Cooling Water 11 82 Diesel Starting Air 12 18 Diesel Fuel Oil 13 1 Main Steam 14 31 HVAC Refrigeration 15 26 Fire Protection 16 77 Waste Disposal 17 78 Fuel Pool Cooling 18 84 Flood Mode Boration (c) Instrumentation The following systems include alternately analyzed instrument lines within the scope of this program. _

Instrument Sensing Sampling and Radiation Monitoring Essential Control Air Al DNE1 - 1655M

s (d) Approximate Quantities Unit 1 Unit 2 Process Piping (feet) 10,000 30,000 Instrument Lines (feet) 300,000 300,000 2.0 Approach Completion of Phase 2 of the Alternate Analysis Review Program will provide confidence that all alternately analyzed process piping, instrument lines, and supports are in accordance with design basis requirements. A general description of the different approaches to be used for process piping and instrument lines is provided below. (Note:

Alternately analyzed non-ANS safety class process piping, which performs a secondary safety function and is required for unit 2 restart has been walked down and evaluated by EQE Incorporated. Similar walkdowns and evaluations are being performed for piping required for unit 1 restart.

This piping is not within the scope of the program described in this document.)

2.1 process Piping (a) Walkdowns 100 Percent walkdowns will be performed for all process piping and supports within the scope of this program. Walkdown drawings will be developed for all piping and associated supports.

(b) Pipe Stress Evaluations Using the information collected by the walkdowns, all process piping within the scope of this program will be evaluated for compliance to the design basis requirements. Evaluation methods will include using a now or revised Alternate Analysis Criteria (i.e., "ecokbook"), performing hand calculations, and performing computer analysis. Support design loads will be _

tabulated for all supports. Support modifications will be specified where necessary.

(c) Support Evaluations Using the information collected by the walkdowns and the loads derived by the piping analysis, all process piping supports will be evaluated for compliance to design basis requirements.

Evaluation methods will include hand calculations and computer analysis. New support designs will be prepared and existing' support designs will be medified as necessary.

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.l 2.2 Instrument Lines (a) Walkdowns )

Walkdowns will be performed for all instrument lines and ,

supports within the scope of this program. Screening criteria  !

I will be used by the walkdown teams to identify instrument lines with overspans, and with thermal expansion and anchor movement flexibility concerns. Sketches will be prepared for portions of these lines which do not pass the screening criteria. Also, problem supports (i.e., supports with marginal designs) and supports that have been significantly varied from standard designs will be identified by the walkdowns and sketched.

(b) Instrument Line Stress Evaluations Using the sketches and information generated for the walkdowns, overspans and areas with flexibility concerns will be evaluated for compliance to design basis requirements. Evaluation methods will include using a new or revised Alternate Analysis Criteria (i.e. , " cookbook"), performing hand calculations and performing computer analysis. Support design loads will be screened against an accepted nominal load and design loads will be tabulated for supports with loads exceeding the nominal value. Support modifications will be specified where necessary.

(c) Support Evaluations Using the sketches and information generated by the walkdowns plus the nominal loads and loads derived by the instrument line analysis, instrument line problem supports, supports with significant variances, and supports with loads greater than the accepted value will be evaluated for compliance to design basis requirements. Evaluation methods will include hand calculations and computer analysis. New support designs will be prepared and existing designs will be modified as necessary.

In addition, a sampling program will be conducted for supports -

outside the areas specifically evaluated to establish confidence that variances to standard support designs have not resulted in unacceptable support configurations.

3.0 Schedule Phase 2 of the Alternate Analysis Review Program (including modifications), will be complete by the end of the cycle 4 refueling outages for both units. The cycle 4 refueling outages will be extended as necessary to permit installation of all Phase 2 modifications.

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TVA/ SON . ALTERNATE ANALYSIS REVIEW PROGRAM .

SCHEDULE YEAR 86 87 88 89 90 MONTH 10 ll 12 1 2 34 5 6 7 8 9 10 11 12 8 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 l

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ESTABLISH b-h(M)

ANALYSIS / SUPPORT EVALUATIONS MODIFICATIONS IMPLEMENTED -

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UNIT I ANALYSIS / SUPPORT EVALUATIONS "

PHASE 2 g uCO FicATIONS IMPLEMENTED I .,

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ANALYSl5 / SUPPORT EVALUATIONS "

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PHASE 2 j MOOlFICATIONS IMPLEMENTED i INSTR EVALUATIONS . I l

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UNIT 2 C4 RESTART l OUTAGE U ( TARGET)

(TARGET) START END (TARGET) -l UNIT I C4 UNIT 4 OUTAGE

. HESTART tTARGET)

(TARGET)

" EVALUATIONS PRIORITIZED AS A FUNCTION OF

, SYSTEM SAFETY SIGNIFICANCE AND ACCESSIBILITY t

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l Enclosure B Sequoyah Nuclear Plant (SQN)

Alternate Analysis Review Program Justification for Limited Walkdowns for Unit 2. Phase 1 I

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j Justification for Limited Walkdowns for Unit 2, Phase 1 For Unit 2, Phase 1, 100 percent walkdowns were performed for piping with operating temperatures above 200 0 F, but walkdowns were generally limited for lower temperature piping to the areas local to other Phase 1 items (i.e.,

motor operated and pneumatic valves, branch /run interfaces, and interfaces with deadweight supported piping larger than 2 inches nominal size). Phase 1 piping evaluations were performed based on the walkdown information.

Evaluation of the Phase 1 items and resolution of associated deficiencies is adequate to ensure that all piping and supports are acceptable for restart.

The selection of the specific Phase 1 items that were addressed has NRC concurrence as noted in the draft Safety Evaluetion Report (Reference 6.2).

Since the Phase 1 items have been determined to be those critical for restart, it follows that limiting walkdowns to piping local to those items is sufficient for restart.

In addition to the evaluation of the Phase 1 items, piping outside the local areas was reviewed for obvious discrepancies using existing drawings.

Walkdowns were performed where drawings could not be located or if information on the drawings was unclear. The existing drawings are sufficiently accurate for the review of piping outside the local areas. Observed discrepancies between the existing drawings and the "as-constructed" piping configuration are generally limited to dimensional differences that are within construction tolerances. Therefore, a review of drawings, rather than performing walkdowns for piping outside the local areas, was justified within Phase 1.

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Enclosure C i SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 l

Instrument Lines and Supports i Issues, Current Activities, and Planned Post-Restart Activities

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CONTENTS P_!yL, 1.0 Purpose. . . . . . . . . . . . . . J. . . . . . . . . . . ..... Cl 2.0 Scope. . . . . . . . . . . . . . . . . . . . . . . . . . ... . .. C1 3.0 Issues and Current Activities. . . . . . . . . . . . . . . .. ... C1 3.1 Instrument Lines. . . . . . . . . . . . . . . . . . ...... C1 3.2 Instrument Line Supports. . . . . . . . . . . . . . ...... C5 3.3 Documentation . . . . . . . . . . . . . . . . . . . . ..... C5 4.0 Planned Post-Restart Activities. . . . . . . . . . . . . . .. ... C6 4.1 Walkdowns . . . . . . . . . . . . . . . . . . . . . . .. ... C6 4.2 Evaluations . . . . . . . . . . . . . . . . . . . . . .. . .. C7 l

4.3 Documentation . . . . . . . . . . . . . . . . . . . . .. . .. C7 '

l 5.0 Actions to Prevent Recurrence. . . . . . . . . . . . . . . ... .. C8 l l

i 6.0 References . . . . . . . . . . . . . . . . . . . . . . . . .. . .. C8

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1.0 Purpose The purpose of this document is to identify issues related to the support of instrument lines, provide information on any current activities related to those items and to define planned post-restart activities.

2.0 Scope This document is applicable to all safety-related instrument lines and supports at Sequoyah Nuclear Plant (SQN). Systems and approximate quantities are listed below:

Approximate Maximum Quantities (per unit)

System Size / Material Temperature Lineal Feet No. Supports Sensing 1/2" Sch 80 Ambient (1) 250,000 35,000 and 160 SS Piping Sampling 3/8", 1/2", 6500 F(2) 50,000 13,000 and 1" SS Tubing Radiation Monitoring Essential 1/2" SS Tubing, Ambient 4,000 750 Control Air 2", 3", 4" Schedule 40 SS Piping (1) Stagnant lines.

(2) Approximately 15,000 feet per unit has operating temperatures above 1200F.

3.0 Issues Following is a summary of generic issues related to instrument lines and supports and information on any current activities related to those issues. Planned post-restart activities are described in section 4.0. .

3.1 Instrument Lines (a) Instrument sensing line slope.

Instrument sensing line slope issues will be addressed in a separate tran.smittal from TVA to NRC.

(b) Overspans for instrument lines with no concentrated weights or with small (less than 15 pounds) concentrated weights.

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A random sample of 60 supports were walked down and evaluated for Employee Concern Task Group (ECTG) Report 173.03, " Missing ,

Instrument Line Clamps," (see issue 3.3(a)). Overspans  !

identified by these walkdowns were evaluated and each case was ,

found to be acceptable (i.e., code allowables were not l exceeded). These evaluations, coupled with experience data and  !

test data which indicate that pipe failures do not occur in similarly-supported piping, provide a sufficient basis for  ;

deferral of additional activities on this issue to post-restart. l (c) Flexibility of instrument lines at interfaces with process linec to accommodate process line thermal and seismic movements.

In Phase I of the Alternate Analysis Review Program, 256 (total scope) branch /run interfaces were evaluated to determine if the branch line had adequate flexibility to absorb run line movements without overstressing the pipe or supports.

Modifications (i.e., support deletions) were made to 70 cases to ensure compliance with design requirements.

Additional evaluations were performed to determine if failures would have occurred had the modifications not been performed.

It was concluded that for some cases support failures were possible, but in no case would the run line movements or support failures have resulted in a pipe failure.

Instrument lines at SQN ere supported similar to the process line branch connections. However, sine, these lines are either 1/2-inch piping or 1 inch and smaller tubing, instrument lines are more flexible than most process line branches. (Nete:

Essential Control Air includes some 2" 3", and 4" piping but this piping does not interface with process piping run lines.)

Therefore, it is concluded that run line anchor movements will not produce failures in instrument lines and no further evaluation is necessary prior to restart.

(d) Flexibility of instrument lines for thermal expansion.

(Sampling and radiation monitoring lines only. Sensing and

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essential control air lines are not subject to significant .

thermal expansion.)

Thermal expansion flexibility was evaluated in the initial design of sampling and radiation monitoring lines at SQN.

Field inspections show that most supports on these lines are guides (2-way supports) and no cases of multiple, in-line, 3-way supports have been observed on lines with operating temperatures greater than 1200F. The first support around a bond is spaced to provide flexibility for thermal expansion and flexible loops are used in long runs. It is believed that the installation is acceptable (i.e., in compliance with design basis requirements), but due to generic problems in the application of alternate analysis methods, it has been decided to verify the adequacy of the original design in the ,

post-restart portion of the alternate analysis review program.

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A very few cases of constrained thermal expansion in sampling and radiation monitoring lines do exist. During field inspection, four 3/8-inch OD sampling lines (2 on each unit) were observed to be bowed in a sine wave shape that is characteristic of constrained expansion of small diameter j tubing. For those lines, the constraint is the result of an

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interference with a fixed object at the end of a long straight ,

run.

Based on calculations and on previous laboratory tests conducted by TVA, it is concluded that bowing is an acceptcble mechanism for relieving thermal expansion in small diameter tubing for which slope maintenance is not essential to functional capability. During heatup, constrained thermal expansion is relieved by approximately equal lateral displacements (bowing) in each tubing span. This has been confirmed in laboratory tests and by inspection of actual ,

installations which are bowed. During cooldown, bowing of the line will be recueed, but for high temperatures (generally greater than 5000 F), it will not be entirely eliminated. In a subsequent heatup, this new equilibrium condition is the starting point of the next thermal cycle.

For the worst-case of a maximum operating temperature of 6500F, the maximum strain (based on test data) is approximately 0.15 percent for the first cycle. This corresponds to an intensified stress (conservatively using i = 1.3) of approximately 49,000 lb/in2, which is within the 3Se allowable of 56,400 lb/in2 permitted by ASHE III for 316 SS subject to a single nonropeated anchor movement. For all subsequent cycles originating from the already-bowed condition, the maximum strain is approximately 0.1 percent, which corresponds to an intensified stress of approximately 33,000 lb/in2 Combining with stress due to precsure and deadweight yields an equation 11 stress of approximately 36,000 lb/in2 , which is within the equation 11 allowable limit for 316 SS at 6500F, even if conservatively assuming 45,000 cycles. (Fewer than 1/3 that many cycles are expected to occur before corrections are made to relieve the constrained -

thermal expansion.) Therefora, allowable stress levels are not exceeded as a result of the constrained thermal expansion and resultant bowing. In addition, slope is not critical for sampling and radiation monitoring lines and, therefore, bowing does not result in slope-related problems.

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The known quality of the initial design, combined with the acceptable bowing of the very few lines with constrained thermal expansion, plus the fact that no failures attributed to inadequate thermal expansion flexibility have occurred during unit operation, provides a sufficient basis for deferral of further evaluations on this issue to post-restart.

(e) Bent or bowed instrument lines.

Some sections of instrument tubing are bent or bowed due to personnel loads and, in rare instances, due to constrained thermal expansion (see item (d)]. This issue applies primarily to relatively light 3/8-inch and 1/2-inch OD tubing (sampling, radiation monitoring, and control air lines), and in some cases to 1/2-inch Schedule 80 and 160 piping (sensing lines). (Since sensing lines are stagnant and not subject to thermal ,

expansion, bends in those lines are due to personnel loads.)

Bends and bowing in sampling, radiation monitoring, and control air lines do not prevent. normal function of those lines (slope is not critical for these systems) and are not a safety concern. However, bends in sensing lines could result in slope problems. To alleviate these concerns, instrument sensing lines that are required for restart and that may be subject to outgassing or air entrapment will be walked down and evaluated before restart. Corrections will be made as necessary to ensure proper slope for these lines.

(f) Instrument line clearances.

Instrument line clearance concerns were identified during recent walkdowns. This issue applies primarily to sampling and radiation monitoring lines which have displacements due to thermal expansion.

Testing of instrument line interferences with adjacent tubes performed by TVA indicate that the moving tube will easily slip by an adjacent tube without resulting in any overstress for either tube. Also, the testing shows that support loads - ,

resulting from tube contact are generally very small and will i not result in clamp failures. Further [as noted in item (d)),

instrument line interferences with fixed objects are relieved by bowing of the tubing without resulting in any overstress.

The results of the interference testing, and the bowing testing and evaluations noted in item (d), provide a sufficient basis for deferral of additional activities on this issue to post-restart.

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3.2 Instrument line supports (a) Missing, loose, damaged, and improperly installed clamps.

In response to ECTG Report 173.03, a random sample of 60 clamps was reviewed to establish confidence that the instrument line and support installations are acceptable. Those 60 clamps, plus 2 clamps on either side of the 60, were walked down to determine the "as-installed" configuration. A total of approximately 300 clamps were actually included in the sample and only 3 clamps were found to be missing. The instrument lines and supports affected by the missing clamps were evaluated and both the instrument lines and clamps were found to be well within allowable stress or 1.ad limits. Also,

" loose, damageo, and improperly installed" clamps were found to be functional and have more than adequate capacity.

When instrument line clamp maintenance items have been identified during the various waltdowns for instrumentation and other issues, appropriate msintenance work has been performed.

Also, maintenance on instrument line clamps has been performed in accordance with Special Maintenance Instruction SMI-0-317-25 (reference 6.1). The sampling program described above indicates that instrument line clamp issues either are not significant or have been corrected through this maintenance process.

In summary, it has been concluded that the ample margin in both the instrument lines and the clamps, combined with the low occurrence of missing clamps, and the insignificance of the

" loose, damaged, and improperly installed" clamps, provides a sufficient basis for deferral of additional activities on these items to post-restart.

(b) Instrument mounting plates, brackets, and bolts incorrect.

Various instrument mounting concerns were identified during recent walkdowns. Additional walkdowns of instruments required for restart will be performed to identify and correct -

instrument mounting inadequacies.

3.3 Documentation Various concerns have been identified regarding documentation for the installation and inspection of instrument lines and supports.

These concerns do not represent a safety problem and will be addressed after restart.

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4.0 Planned Post-Restart Activities The following describes planned post-restart activities to fully resolve the issues identified in section 3.0 and ensure that all instrument lines and instrument line supports are in compliance with design basis requirements.

4.1 Walkdowns Walkdowns will be performed for all safety-related instrument lines and supports. These walkdowns, along with the evaluations described in section 4.2, will provide confidence that all instrument lines and supports are in accordance with design basis requirements.

These waltdowns will develop the "as-constructed" configuration for instrument lines and supports which do not pass screening criteria developed for the walkdowns.

4.1.1 Walkdowns for instrument line and support stress issues.

A walkdown program will be developed to identify situations that may be significant for instrument line and support stress. Walkdowns utilizing a screening criteria will be used to identify overspans, and to identify potential problems with seismic and thermal anchor movement flexibility and thermal expansion flexibility. For supports, a screening criteria will be used to identify problem supports (e.g.,

marginal designs) and supports that have been varied significantly from the standard design. Skotches will be prepared for those instrument lines and supports that need additional analysis to assure compliance with design basis commitments.

4.1.2 Walkdowns for installation issues.

A walkdown program will be developed to address instrument line and clamp installation issues. These walkdowns will identify and correct damaged and improperly installed instrument lines and clamps (including torqueing clamp bolts, as required) to ensure compliance with design basis -

commitments.

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4.2 Evaluations Using the sketches generated by the walkdowns, evaluations will be performed (see below for criteria) for instrument lines and supports that do not pass the walkdown screening criteria. Modifications will be performed as necessary to ensure compliance with design basis requirements.

In addition, a sampling program will be conducted to establish confidence that variances to standard support designs have not resulted in unacceptable support configurations.

Criteria for Evaluation of Instrument Lines and Supports Instrument Lines - SQN-DC-V-13.3, "SQN - Design Criteria for Detailed Analysis of Category I Piping Systems."

In addition, a strain based criteria similar to that proposed in ASME Code Case N-196 may be proposed for the evaluation of instrument lines. If so, detailed information and justification for that critoria will be provided in a future transmittal.

Instrument Line Supports - SQN-DC-V-24.1, "SQN - Design Criteria for Location and Design of Piping Supports and Supplemental Steel in Category I Structures."

4.3 Documentation Documentation for the qualification of instrument lines and supports will consist of the following:

(a) Walkdown packages with data sheets for all instrument lines and supports, and with sketches for all instrument line and support configurations which do not pass the walkdown screening criteria.

(b) Evaluations of instrument line and support configurations which do not pass the walkdown screening criteria, based on the sketches developed by the walkdowns.

(c) Issued drawings for supports that are required to be modified.

(d) Sampling program showing that variances to standard support designs are acceptable.

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5.0 Actions to Prevent Recurrence Existing procedures will be revised and new procedures will be developed to address all instrument line and support issues and prevent recurrence of similar problems in future installations. Procedure revisions and new procedures will include:

(a) Procedures will be revised to eliminate the future use of variances on instrument line supports. All future changes will be made using issued drawings.

(b) An " Engineering Requirements Specification" for instrument line installation and inspection will be issued for SQN. Existing installation and inspection procedures will be revised and new procedures will be issued to implement this specification.

(c) The instrumentation drawings and typical support drawings will be revised to upgrade and clarify design requirements.

6.0 References 6.1 SMI-0-317-25, SQN - Special Maintenance Instruction " Inspection and Corrective Maintenance of Small Diameter Instrument and Sensing Lines."

6.2 B. J. Youngblood's letter to S. A. White dated December 19, 1986 (A02 861222 032).

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ENCLOSURE D SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 l

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s TVA/ SON ALTERNATE ANALYSIS REVIEW PROGRAM PROGRAM STRUCTURE UNIT 2 : PHASE I y7PROGRAM ,,,,/SCOPE '

PIPING WITH /

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PIPING DESIGNED BY ALT. ANALYSIS WITHIN DVBP SCOPE PIPING DESIGNED BY ALTERNATE ANALYSIS TOTAL PLANT PIPING SYSTEMS IN UNIT 2 AND COMMON u------- . - - - - - - - - - - - - _ - - - - - - - - - - - - - - - _ _ _ _ _ -__

ENCLOSURE E' .

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SEQUOYAH NUCLEAR PLANT ALTERNATE ANALYSIS PHASE II PROGRAM COMMITMENTS

1. Phase II of the Alternate Analysis Program will be complete by the end of the cycle 4 refueling outage for each unit. The program scope will include walkdowns, pipe stress evaluations, and support evaluations for process piping and instrument lines.

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