ML20045F727

Responds to Request for Addl Info Re ASME IST Program & IST Program Relief Request V-5.Licensee Will Revise IST Program to Withdraw Relief Request & to Specify Appropriate Code Test Requirements for Check Valves

ML20045F727
Person / Time
Site:	Comanche Peak
Issue date:	07/01/1993
From:	William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TXX-93237, NUDOCS 9307080309
Download: ML20045F727 (7)

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Log # TXX-93237 Fi1e # 10010 l---

_ _ _- Ref. # 10CFR50.55a(f)(4)

TUELECTRIC July 1, 1993 William J. Cahill, Jr.

Group Vire President U. S. Nuclear Regulatory Commission ,

Attn: Document Control Desk .!

Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET N05. 50-445 AND 50-446 REQUEST FOR ADDITIONAL INFORMATION, ASME INSERVICE TEST PROGRAM AND INSERVICE TEST PROGRAM RELIEF REQUEST V-5 REF: 1) TU Elect' Letter logged TXX-93029 from William J. Cahill, Jr., to the NRC dated January 21, 1993  !

2) NRC Safety Evaluation dated January 29, 1993, for CPSES Unit 1

3) Appendix R of Supplement No. 26 to NUREG-0797 Related to the Operation of Comanche Peak Steam Electric Station, Unit 2 (February 1993)

Gentlemen:

On January 21, 1993, via Reference 1, TU Electric committed to provide a .

report describing the process used in the development of the CPSES ASME Boiler and Pressure Vessel Code Section XI Inservice Test Program (IST) (See Attachment 1) and to address concerns regarding IST Relief Request V-5 (See Attachment 2). Included in Attachments 1 and 2 are clarifications of statements from References 2 and 3. If you have any questions please contact Mr. Carl B. Corbin at (214) 812-8859.

Sincerely, i Y&

• William J. Cahill, Jr.

CBC/bm Attachments c- Mr. J. L. Milhoan, Region IV Resident Inspectors, CPSES (2)

Mr. T. A. Bergman, NRR ,

Mr. B. E. Holian, NRR l l

NcA1 9307080309 9307oy_ y3 l p DR- ADOCK 05000445 $N h ,{I  !

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$50 N. Olive Street LB. 81 Dallas, Texas 75201  !

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Attachment 1 to TXX-93237 Page 1 of 5 IST PROGRAM DEVELOPMENT PROCESS The referenced NRC safety evaluations requested that TV Electric provide the NRC staff with a description of the process used in the development of the CPSES IST Program. Specifically, information was requested regarding details of the documents used, the method for determining which components require inservice testing, the basis for the required testing, the basis for categorizing valves, and the method or process used for maintaining the program current with design modifications or other activities performed l under 10CFR50.59. The details below are provided for your information. 1 Future revisions of the IST Plan and supporting documentation will be I available on site.

l Documents In addition to the documents listed in Section 1.5 of the CPSES IST Plan, the following documents were used in the development of the IST Program:

Applicable portions of CPSES Licensing Basis Documents including FSAR, Technical Specifications and Bases, Technical Requirements Manual, and the IST Plan; CPSES Design Basis Documents (which compile details of design, operation, testing, and compliance with codes & standards, on a system basis);

Other CPSES design documents including drawings, equipment  ;

specifications, calculations and analyses-r Vendor documents including drawings, correspondence, and maintenance &  ;

operation manuals; and Applicable portions of NUREG-0797, " Safety Evaluation Report related to the operation of CPSES Units 1 & 2", including supplements.

l Method for Determinina Scope The method for determining which components require inservice testing is ,

described in CPSES IST Plan, Section 2.2, " Scope (of the Inservice Pump Testing Plan)" and Section 3.2, " Scope (of the Inservice Valve Testing  ;

Plan)." As indicated in those IST Plan sections, the active components included in the IST Program are those active pumps, valves and pressure relief devices which are described and listed in FSAR Sections 3.9N.3.2 and '

3.98.3.2, " Pump and Valve Operability Assurance." Thus, the inservice test program scope is maintained consistent with the licensing basis for active  ;

components.

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i j Attachmert 1 to TXX-93237 Page 2 of 5  :

The FSAR classification methodology for active components is taken from Regulatory Guide 1.48 and includes those pumps, valves and pressure relief '

devices "that must perform a mechanical motion during the course of accomplishing a system safety function." System safety functions are defined to include any function that is necessary to assure (1) the '

integrity of the reactor coolant pressure boundary, (2) the capability to shutdown the reactor and maintain it in a safe shutdown condition, or (3) the capability to prevent or mitigate the consequences of accidents which t could result in offsite exposures comparable to the guideline exposures of 10CFR100. This active component classification methodology and the wording of the scope statements of ASME/ ANSI OM (Parts 1, 6 and 10) are considered  ;

to mean the same thing (i.e. pumps, valves and pressure relief devices  ;

performing nuclear safety functions).

The passive valves in the CPSES IST Program were identified through individual system reviews. The passive valves include those valves which are required to perform a nuclear safety function (as defined above) by

• maintaining their position and for which ASME/ ANSI OM Part 10 specifies (

leakage testing or position indicator testing requirements. l t

ASME/ ANSI OM Part 1 provides requirements for pressure relief devices which f 4

are required to perform a specific function in shutting down a reactor or in  !

mitigating the consequences of an accident. Consistent with ASME/ ANSI OM- t 1987 Interpretation No. 1-2 and the FSAR active component classification methodology described above, the CPSES IST Program scope includes those  ;

4 pressure relief devices which themselves perform an active nuclear safety .

l function. TU Electric notes that the referenced NRC safety evaluation for ,

CPSES Unit 2 reflects this position (page 2 of Reference 3). The discussion

, of IST Program scope in the Unit 1 safety evaluation (pages 2 and 6 of Reference 2) should be clarified to reflect this position.

i Basis for Testino recuirements 1

The basis for the testing specified for components in the CPSES IST Program is ASME Section XI. In the case of pump testing, ASME/ ANSI OM Part 6

, identifies test requirements based on considerations of.1) pump type, 2) method of pump speed control, 3) arrangement of the pump relative to its driver, and 4) accessibility of pump bearing housings. The CPSES IST. Plan applies these considerations to each pump in the program via a pump classification methodology and specifies the Code required pump test parameters based on the particular class of pump. (Reference IST Plan, Section 2.0). The basis for any pump testing which deviates from the ASME Section XI requirements is described in a relief request which identifies-the deviation. (Reference IST Plan, Appendix A.)

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Attachment 1 to TXX-93237 Page 3 of 5 In the case of valve and pressure relief device testing, ASME/ ANSI OM Parts 1 & 10 identify test requirements based on considerations of 1) valve and j actuator type, 2) ASME/ ANSI OM Part 10 category, and 3). active or passive i function. The CPSES IST Plan applies these considerations to each valve and pressure relief device in the program in order to determine the appropriate l Code test parameters (Reference IST Plan, Section 3.0). The basis for any i valve or pressure relief device testing which deviates from the ASME Section '

XI requirements is described in a Relief Request which identifies the deviation (Reference IST Plan, Appendix A).

Basis for Cateaorizino Valves The basis for categorizing valves in the CPSES IST Program is ASME/ ANSI OM l Part 10. ASME/ ANSI OM Part 10 requires all valves in the IST Program to be classified as either Active or Passive and to be categorized as A, B, C or D, as defined below. l Active Valves - Valves which are required to change obturator position i to accomplish the required [ nuclear safety] function (s).

Passive Valves - Valves which maintain obturator position and are not-required to change obturator position to accomplish the required (nuclear safety) function (s).

Category A - Valves for which seat leakage is-limited to a specific maximum amount in the closed position for fulfillment of their required

[ nuclear safety] function (s).

Category B - Valves for which seat leakage in the closed position is inconsequential for fulfillment of their required [ nuclear safety]

function (s).

Category C - Valves which are self-actuating in response to some system characteristic, such as pressure (relief valves) or flow (check valves) for fulfillment of their required [ nuclear safety] function (s).

Category D - Valves which are actuated by an energy source capable of only one operation, such as rupture disks or explosively actuated ,

valves.

The ASME/ ANSI OM Part 10 valve classification requirements are interpreted for use in the CPSES IST Program as follows:

i Cateoorv A. Active is used to designate active, power operated or manually j operated valves which have seat leakage limits in the closed position. '

Valves in this category are subject to the position indication verification requirements of ASME/ ANSI OM Part 10, para. 4.1 (if applicable), the exercising tests requirements of ASME/ ANSI OM Part 10, para. 4.2.1, and the seat leakage rate test requirements of ASME/ ANSI OM Part 10, para.'4.2.2.

Attachment 1 to TXX-93237 Page 4 of 5 l Cateaory A. Passive is used to designate passive valves of any type which have seat leakage limits in the closed position. Valves in this category are subject to the position indication verification. requirements of-ASME/ ANSI OM Part 10, para. 4.1 (if applicable) and the seat leakage rate test requirements of ASME/ ANSI OM Part 10, para. 4.2.2. .

Cateaory B. Active is used to designate active, power operated or manually 't operated valves which do not have seat leakage limits in the' closed position. Valves in this category are subject to the position indication  ;

verification requirements of ASME/ ANSI OM Part 10, para. 4.1 (if applicable) ,

and the exercising test requirements of ASME/ ANSI OM Part 10, para. 4.2.1.  !

Cateaory B. Passive is used to designate passive, power operated or manually .

Operated valves which do not have seat leakage limits in the closed >

position. Valves in this category are subject only'to the position '

indication verification requirements of ASME/ ANSI OM Part 10, para. 4.1 (if j applicable) and are only listed in the IST Plan if position indication verification is applicable, j t

Cateaory C. Active is used to designate active, self actuated valves ,

(pressure relief devices and check valves) which do not have seat leakage i limits in the closed position. Valves in this category are subject to the )

position indication verification requirements of ASME/ ANSI OM Part 10, para.

4.1 (if applicable) and the performance test requirements of ASME/ ANSI OM  ;

Part 1 for pressure relief devices or the exercising test requirements of  ;

ASME/ ANSI OM Part 10, para. 4.3.2 for check valves, as applicable.

• Cateaory A/C. Active is used to designate active, self actuated ~ valves I (pressure relief devices and check valves) which have seat leakage limits in

• the closed position. Valves in this category are subject to the position >

indication verification requirements of ASME/ ANSI OM Part 10, para. 4.1-(if' -l applicable), the performance test requirements of ASME/ ANSI OM Part-1 for i pressure relief devices or the exercising test requirements of ASME/ ANSI OM Part 10, para. 4.3.2 for check valves, as applicable, and the seat leakage ,

rate test requirements of ASME/ ANSI OM Part 10, para. 4.2.2. (Seat Leakage l rate testing is performed as part of the overall performance test for Category C, Active pressure relief devices and may be used to verify a full-stroke exercise to the closed position for somo Category.C- Active check valves. However, these pressure relief devices and check valves are classified as Category A/C only if some safety analysis criteria exist for valve seat leakage such as when they are used as containment isolation valves.)

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Attachment 1 to TXX-93237 Page 5 of 5  !

Cateaory B/C. Active is used to designate the category for the Pressurizer ]

Power Operated Relief Valves (PORVs). This designation is used in ,

recognition of the ASME/ ANSI OM Part 10 requirements for testing Category B I Active, power operated valves as well as the ASME/ ANSI OM Part 1 )

requirements for testing Category C Active, power operated relief valves.  !

Note that ASME/ ANSI OM Part 1 only specifies test requirements for ASME 1 Class 1 power operated relief valves. The Pressurizer PORVs are subject to  !

the position indication verification requirements of ASME/ ANSI OM Part 10,  !

para. 4.1, the exercising test requirements of ASME/ ANSI OM Part 10, para.

4.2.1, and the applicable performance test requirements of ASME/ ANSI OM Part 1.

There are no Category D valves in the CPSES IST Program.

Process for Maintainina the IST Proaram Current The process for maintaining the CPSES IST Program current with design modifications is integral to the design modification process. Design modifications are reviewed prior to implementation by a subcommittee of the  :

Station Operations Review Committee (SORC) for impact on plant programs, procedures, etc. Any required IST Program changes identified during the subcommittee review are incorporated into the implementation schedule for i the design modification and are accomplished at the appropriate schedule milestone. During the closure phase of the design modification process, all  ;

required changes to plant programs, procedures, etc. are verified complete. 3 The method for maintaining the CPSES IST Program current with other activities performed under 10CFR50.59 is the 10CFR50.59 review process. The process requir es preparers of 10CFR50.59 reviews to identify instances where a proposed activity will result in a change to the facility or procedures as described in the Licensing Basis Documents. In such cases, the preparer is ,

required to initiate changes to the affected Licensing Basis Documents. The  !

CPSES IST Plan is a Licensing Basis Document and therefore is explicitly i considered under the 10CFR50.59 review process. ,

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l Attachment 2 to TXX-93237  !

Page 1 of 1  !

1 RELIEF REOUEST V5 ,

The reference NRC safety evaluations (References 2 and 3) denied IST Program Relief Request V5 for the inservice testing of CPSES Units 1 & 2 and i directed TU Electric to either revise and resubmit the relief request or to  !

develop a test method which complies with the ASME Code requirements and  :

withdraw the relief request. The safety evaluations further stipulated that  !

the substitute test proposed in Relief Request V5 is acceptable until the i appropriate action is taken by TU Electric to resolve the NRC. staff l concerns. However, this action must be taken prior to startup from the .

third refueling outage for Unit 1 (1RF03) and prior to startup from the l first refueling outage for Unit 2 (2RF01). j TU Electric has determined that the appropriate resolution for this issue is l to implement the required ASME Code tests for the check valves addressed by i Relief Request V5. Therefore, the CPSES IST Program will be. revised to  !

withdraw the relief request and to specify the appropriate Code test i requirements for these valves. This IST Program revision will be completed l prior to the third refueling outage for CPSES Unit 1 such that the required '

testing can be accompi"shed for the Unit 1 valves prior to startup from the third refueling on Unit 1 (1RF03) and can be accomplished for the Unit 2 valves prior to startup from the first refueling on Unit 2 (2RF01). In the meantime, the substitute test described in Relief Request V5 will continue to be implemented for the check valves in both units.

1 Also, TU Electric would like to clarify the test method which is currently being used to implement the substitute testing described in Relief Request j V5. The referenced NRC safety evaluations contain comments which suggest ,

that the intent of the close exercise test for the check valves addressed by l the relief request may not be met if the test connections used to determine valve closure are located downstream (RCS side) of the check valve pairs.

The comments in the safety evaluations, however, seem to be based on a review of FSAR piping isometric figures which depict the piping containing l the subject check valves. (The FSAR figures are not specifically identified l in the safety evaluations but TU Electric assumes the referenced figures to l be 3.6B-75 and 3.6B-78 through 81.) The intent of these FSAR figures is to I describe the postulated pipe break locations and restraint locations for these lines. These figures contain only the information required to meet this intent and do not necessarily show all test connections for the lines.

By referring to FSAR Figure 9.3-10, sheets 4 and 5 which depict the Chemical l and Volume Control System configuration, it can be seen tnat sufficient test '

connections and test boundary valves are provided upstream of the subject check valves to conduct the type of substitute testing described in_ Relief Request V5. The current test method uses those upstream test connections and boundary valves for testing the check valve pairs identified in Relief Request V5 and is considered adequate to verify valve closure. .

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