ML20042D338

Forwards Response to Generic Ltr 89-10, Safety-Related Motor-Operated Valve Testing & Surveillance. Util Will Comply W/Ltr Recommendations W/Noted Exceptions.Response to Be Completed When Ltr Uncertainties Cleared

ML20042D338
Person / Time
Site:	Peach Bottom, Limerick, 05000000
Issue date:	12/28/1989
From:	Helwig D PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-89-10, NUDOCS 9001090011
Download: ML20042D338 (17)

Text

, . _ _

'10 CFR 50.54(f)' -

. il PHILADELPHIA ELECTRIC COMPANY l i

NUCLEAR GROUP HEADQUARTERS  :

955-65 CHESTERBROOK BLVD.

y WAYNE PA 19087 5691-(215) 640 6650 '

l DAVID R. HELWIG  :

vies ens.m== -

NUCLE AR SERVICES . December 28,.1989-s Docket Nos. 50-277-50-278 50-352' 50-353. I

?;

' License Nos'.-DPR-44.  :

DPR-56 :i NPF .-

NPF-85 4 U.S.-Nuclear Regulatory Commission Attn: Document Control Desk

• Washington, DC 20555 '

SUBJECT:

Peach Bottom AtomicePower' Station, Units 2-and.3 Limerick Generating Station, Units lJand 2 Response to Generic Letter 89-10, " Safety-Related-Motor-Operated Valve Testing:and Surveillance _10LCFR150.54(f)" _(l Gentlemen:

response Attached is the Philadelphia to NRC Generic Letter 09-10.- Electric Companyi(PECo)? .

PECo-w311 comply.with the .

Generic response.

Letter-recommendations with_some' exceptions as noted:in the followed by~the Each Generic PECo Letter 89-10 recommendation Isirestated' response. Because of the manyl uncertainties '

1 surrounding.this Mr. T. Generic Letter,:some of which are the subject of Tipton's (Nuclear Management and Resources' Council): November-17, 1989 -l letter to Dr. T. Murley (NRC), PECo is' unable to make a-complete response at this time.- PECo.is actively involvedLin. '

industry initiatives to meet'the-intent of~the Generic' Letter and l

will efforts.

complete its response based on the useful.results;of-those If you.have any questions, or require additional information, please contact us.

Very,truly yours,_

P 0^1 891228

?D$**l0GCKosooop77 y' r ~

4 p PDC i

-Attachment " .

jf-cc: W. T.. Russell,-Administrator, Region'I, USNRC J. J. Lyash, USNRC Senior Resident Inspector, PBAPS c r Ok b

T. J. Kenny, USNRC Senior. Resident Inspector, LGS' a

'i . g((g

+s

, COMMONWEALTH'O'P PENNSYLVANIA :

' ss..

COUNTY OF CHESTER  :

-r D. R.'Helwig, being first duly sworn, deposes'and.says:-

That.he is Vice President of Philadelphia ElectricLCompany,.

t that he has read.the response to Generic Letter.No. 89-10, and knows: "

the contents thereof; and that'the statements and matters set forth

• therein are true and correct to.the best ofLhis knowledge,.

information and belief.  !

( ..

W l

Vice President

/

Subscribed and sworn to b e f o r e m e t h i s ,2 8 ay

• of Dec.emhh-1989.

vtWL 6nn e o ,

Notary'Public t

.. flOTARIAL SEAL f ANGELA O. OLENGINSKL Notary Public -

.. . Wayne, Chestor Coune/

My Commissroo Expires Sect. 31.1992 '

/

DockGt Nos. 50-277-1e 1. - .

50-2781 -

50-352- .

50-353  :

Philadelphia Electric Company l Response to NRC Generic Letter 89-10,,

" Safety-Related Motor-Operated Valve l Testing and Surveillance - 10 CFR 50.54(f)" ,

8 Scope <

i By this letter, the NRC extends the scope.of the program outlined in

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Bulletin 85-03 and Supplement'1 of the Bulletin 85-03 to include all-safety-related MOVs as well'as all position-changeable?MOVs-as defined below. The licensee's. program should provide for;the--

testing, inspection, and maintenance of MOVs'so as to. provide the-necessary assurance that.they will function when subjected to.the design-basis conditions that are to be considered duringlbothinormal operation and abnormal events within the design-basis of the plant.

Although this program should address safety-related MOVs and position-changeable MOVs as a minimum,'NRC envisions that,1asipart; of a good maintenance' program, other MOVs in the-balance-of: plant should be considered for inclusion in the program,; commensurate'withs -

the licensee's assessment-of their importance to safety..

.c Any MOV in a safety-related system that is not blocked from inadvertent operation from either-the control room,-the motori ,'

control center, or the valve-itselfLshould be consideredi capable of-being mispositioned (referred to'asLposition-changeable MOVs) and '

should be included in the program. WhenfdeterminingLthe maximum differential pressure or flow for. position-changeable MOVs,sthe fact- -

that the MOV must be able to recover from mispositioning:shouldibe considered. ,

Response to Scope:

Philadelphia Electric Company (PECo)cextended the scope of the Peach- ~

Bottom motor-operated valve (MOV) program beyond'that; required by. ,

Bulletin 85-03 to all MOVs in the piping of-safety-related sys'tems, '

as well as selected balance of plant MOVs. Some non-safety-related' '

MOVs were included based on plant safety and reliability-functions, j accident and transient analyses as described in-the Peach Bottom-Atomic Power' Station Updated Final SafetyLAnalysis. Report--(FSAR')

Chapter 14, accident and post-accident-accessibility 1and" normal- l operating requirements. Each of these.MOVs was: evaluated against

Doc'kat ' Nb3. 50-277 )

' 50-278 >

50-352 j

.50-353- 1 i

'its intended design function. Based on similar criteria, Limerick.

valves will be selected by June 1,-1990. 'i l

Item a)

Review and document'the-design basis-for;the operationio'f each MOV. -

This documentation should' include'the_maximumsdifferential pressure l expected during both the openingtand closing.of'the MOV,for;both' normal operations and abnormal events,-.to the extent.that-these-MOV l

operations and events are included- in the existing. approved design:  ;

basis. "

Response'to Item a)

.i The differential pressure design basis review was-completedifor the ,

MOVs in the High Pressure Coolant l Injection andLReactor Core Isolation Cooling.systemsLat both1 Limerick and Peach Bottom using. 1 methodology developed by_the Boiling Water ReactorLOwner's Groupf ,

(BWROG) for NRC Bulletin 85-03i .For-the remaining' safety related Peach Bottom MOVs.and non-safety-related? Peach Bottom MOVsiincl0dedL M in the program, scenario based methodologies: patterned after1those lr developed by the BWROG for NRC Bulletin-85-03Lwere:used to? calculate-design basis differential pressures.- PECo considers ihisfaction item complete for Peach Bottom. A'similar approach willbe:takensto complete the Limerick design-basis reviews by_ April 1, 1992~. .

H Item b)

Using the results from item a, establish the-correct. switch'~ l settings. This should include establishing a-program to reviewLand revise, as necessary, the methods:for selecting-and setting _alli..

switches (i.e., torque, torque bypass, position limit, overload)sfor each valve operation (opening and closing)'. One purpose!of this- ,

letter is to ensure that a program exists;for selecting _and setting i

i

4 -

'Dockot'Nos.5'04 27f {

50-278: '

'50-352 e 50-353-(

valve operator-switches to ensure high-reliability of safety-related MOVs. ,

Response to Item b)-

PECo has developed MOV switch setting guidelines (1.e.,' criteria) and implementing procedures as part of its Bulletin _85-03' program.

MOV switches at Peach Bottom were set in accordance with<these procedures based on the completed design-basis reviews._ Limerick' ,

MOV switches were set in accordance with procedures as) described in

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PECo's (J. S. Kemper) November 17, 1987 letter to the.NRC. Upgraded-t procedures are being established at Limerick and will begin place <by-May 31, 1990. These procedures willibe periodicallyLreviewed.in accordance with PECo policies.

Item c) L Individual MOV switch settings should be1 changed,,as appropriate,fto-those established in response to item-b.. Whether -.the : switch- 3 settings are changed or not, the MOV should be demonstrated to be operable-by testing it at the design-basis differential pressure and/or flow determined-in response-to item a. Testing MOVs at design-basis conditions-is not' recommended where such testing.is precluded by-the existing plant configuration. An explanation:

should be documented for any cases whereitesting with the design- .

basis _ differential pressure or flow cannot practicably ~be performed.

This explanation should include a description of;the alternatives to design-basis; differential pressure testing.or flow testing /that will-be used to verify the' correct settings..

' NOTE:

This letter is not intended to establish a recommendation'for.

- valve testing for the condition simulating a line break in the line-containing the MOV.- However, a break in:the.line should be-considered in the analysis described in items a., b., and1c. if MOV-operation is relied on.in the' design basis.-

'l

Dockst No3,+50-277 -j

• i- ',- ~

50-2781 50-352 4 50-353' q Each MOV-should be stroke. tested, to; verify thatathe MOV:is' operable 'I at no pressure or no-flow conditions even if testing with differential pressure or flow cannot be performed.

Response to item c)

MOV switches have been set in accordance with switch' setting

~

a procedures as discussed in the response to Item'(b) and selected )

differential-pressure testing at or near_dealgn-basis' conditions has been performed to demonstrate operability and verify.the-adequacy.of the switch settings. Any necessary adjustments to Limerick switch" settings will be made after the design-basis reviews are complete._

At this. time PECo is not prepared to commit to performing additional' in-plant differential pressure and/or-flow (DP/ flow) testing. ..PECo" is participating in industry efforts to better characterize MOV-operating and maintenance requirements.and will considerLadditional industry efforts aimed at alternatives to in plant testing. .PECo  !

requests approximately two years to complete'its response to.-Item.-

(c) of the Generic Letter in order to. allow t'ime-to-evaluate' '

alternatives to in plant testing and to develop a MOV design-basis i testing plan which can be based on.more complet'e an'? d reliable information. The following points justify this request..

l

1. During'the differential pressure testing alreadyr conducted' l at Peach Bottom and Limerick, following. application of diagnostics, no failures to function occurred ~. Eighteen-MOVs on' Peach Bottom Unit 2 have been differential pressure tested in' response to Bulletin 65-03 and' twenty-four.MOVs Dockot Nos.. 50-2771 .

50-278:

50-3521 50-353 on Limerick Unit I have been differential-pressure tested- l either during preoperational tests or'in response to Bulletin 85-03. These tests and-the results have'given

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PECo confidence.that the switch setting methodology and .

' diagnostic techniques used are: valid.

p

2. The Component Failure Analysis =Reportisystem of the INPO Nuclear Plant Reliability Data System (NPRDS)11ndicates'

~

thatLimerickUnitl'MOVfailure~ratesLa[S.substantially-lower than the industry average-(over sixttimes~lowerifor-the period 1/88_to 6/89). PEColbelieves these. low failure.

rates are the result of the extensive 1and elaborate MOV '

rebuilding program instituted at Limerick: Unit- 1 prior; to : h initial fuel loading. A similar program wasLcompleted on -

Limerick Unit 2 prior'to 1nitialsfuel-loading land at Peach

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Bottom prior to'each unit's restart from the most-recent 'I outages. These programs' addressed inspections, testing, (

, (including diagnostics), refurbishment, . procedure development, training, documentation ofJcorrective actions, 4

replacement parts:and quality control.L Diagnostic testing i of safety-related valves,osome non-safety-related.'alves'in v

safety systems, and some valves in balance-of plant systems was performed. Consequently, low MOV failure rates similar' 4

to the Limerick Unit 1 experience are anticipated at: Peach' Bottom and Limerick Unit 2.

1 o

R

l Dockst Non 50-277~

50-278-50-352

50-353

3. Alternatives to'in plant testing need to be examined-because=of the following reasons. (A) Differential pressure testing of many additional MOVs would. require 1 thel plants to be placed in unusual-configurations and unique conditions which: increase the probabilityfof safety. i system challenges and the.potentialffor damage-to:important.

equipment and structures. -(B) Numerous MOVs are' inaccessible or,are located in1high radiation fields when c differential pressure testing conditions couldl practically be established. Since testing requires' hands-on work at, the MOV, testing MOVs in highcradiation~' fields or areas that could become h'igh ra'diation fields due to test activities would be contrary to keeping personneliradiation exposure as low as-reasonably achievable-(ALARA).. (C)

Testing by Kraftwerke Union-(KWU) indicates that

~

differential pressure-testing of MOVs.is likely to cause <

1 accelerated wear.and-deterioration of-MOVLcomponents (resulting in increased friction factors,lfor example)'

which could decrease on-demand' reliability.. ~

I 4.

Y, l

q 1

i l

1

.]

l l

' ' DockGt Nos. 50-277 50-278 50-352 50-353 -

Item d)

Prepare or revise procedures to ensure that correct switch settings are determined and maintained throughout the life of the plant.

-These procedures.should. include-provisions to monitor MOV performance to ensure the switch settings are' correct. This is  :

particularly;important if the-torque or torque bypass switch setting.  !

has been significantly raised above that required.

It may become necessary to adjust MOV switch settings because of the effects of wear or aging. 'Therefore, it is. insufficient to merely verify that the switch settings are unchanged from previously -

established values. The switch settings should be verified in accordance with the program schedule (see item j.). The ASMEfCode Section XI stroke-timing test required by 10 CFR part 50 is not' oriented.toward verification of switch settings - Therefore, '!

additional measures should be taken to adequately verify that the switch settings ensure MOV operability. The switch settings need '

not be verified each time the ASME Code stroke-timing test is performed.

i Response to Item d) 4 PECo has procedures in place, as noted in the response to-Item (b),

to implement correct switch settings on MOVs at Peach Bottom and will have similar procedures in place at Limerick' by May 31, 1990..

The existing preventive maintenance programs at' Limerick and Peach I

i t Bottom are under revision to incorporate diagnostics for assuring.

that correct' switch settings are-maintained, as described in the i response to Item.(j).

L Item e)

Regarding item a, no change to the existing plant design basis 1s-intended and none should be inferred. The design-basis review <

should not be restricted to a determination of estimated maximum design-basis differential pressure, but should include an examination of the pertinent design and installation criteria that were used in choosing the particular MOV. For example, the review.

l  !

'- '? Docket Noss-50-277c

' 50-278-50-352.

.50-353 should include the effects on MOV performance of design-basis-degraded voltage, including the capability of the MOV's power supply and cables to provide _the high initial current'.needed for the operation of the~MOV.

Response to Item e)

The differential pressure design-basis reviews are complete for. '

Peach Bottom and will be completed for Limerick by-April 1,.1992.

{

DC motor cable sizing and the effect of ambient motor temperature on actuator capabilities have been evaluated for Limerick.andLPeach--

Bottom in response to Information Notice 88-72, " Inadequacies'in the Design of DC Motor Operated Valves." Corrective. actions identified' by the evaluations have been completed, thus providing' assurance i that sufficient current will be supplied to the DC MOVs.-

A voltage regulation study'(AC/DC) was performed for' Peach' Bottom 1

Class lE power supplies in 1988 (see Marcht6, 1989 letter..to NRC from PECo). Corrective actions' identified by_the study and_ field measurements and tests to validate the study model'have been .y

\

completed, thus providing assurance that the Peach. Bottom. power supplies are adequate for design basis conditions. Electricall measurements and tests during the Limerick Unit 1 and' Unit 2 startup j programs assured the adequacy of Limerick power _ supplies (see_

~

response to Question 430.38 in Volume 18 of the Limerick FSAR).

AC motor cable sizing and any potential effects of motor ambient j temperatures will be evaluated for Limerick and Peach Bottom by.

December 31, 1991.

l i

• ' Dockot Nos. 50-277

- 50-278 ,

50-352 '

50-353 Item f)

Documentation of explanations and the description of actual test method used for accomplishing item c. should be retained as part of the required records for the MOV.-

It is also recognized that it may be impracticable to perform in situ MOV testing at design-basis degraded. voltage conditions.

However, the switch settings established in response to item b. ,

should at least be established to account for the situation where '

the valve may be called on to operate at design-basis differential pressure, or flow, and under degraded voltage conditions. If the licensee failed to consider degraded voltage,Lpower supply, or. cable adequacy for MOVs in systems covered by Bulletin 85-03, the design .

review and established switch settings for those MOVs should be reevaluated.

Alternatives to testing a particular MOV in situ at design-basis pressure or flow, where such testing'cannot practicably be performed, could include comparison with appropriate design-basis test results on other MOVs, either in situ or prototype. If.such test information is not available, analytical methods and extrapolations to design-basis condition, based on the best data available, may be used until test data at design-basis conditions become available to verify operability of the MOV. _If.this two-stage approach is followed, it should be accomplished within the schedule outlined in item 1. and would allow for MOV testing and surveillance to proceed without excessive delay.

Testing of'MOVs at design-basis conditions _need'not be. repeated unless the MOV is replaced, modified, or! overhauled to the extent that the licensee considers that the existing test results are not-representative of the MOV in its modified configuration.

Response to Item f)

Records will be retained as recommended in accordance with PECo  ;

procedures. The schedule for appropriate DP/ flow testing:and' alternatives to DP/ flow testing will be addressed'in-our subsequent response to Item (c). Degraded voltage, power supply adequacy and- '

cable sizing are addressed in the response to Item (e).

. s-Dock @t:Nos. 50-277

' 50-278 50-352 50-353 Item g)

A number of deficiencies, misadjustments, and degraded conditions-were discovered by licensees, either as a result of their efforts to comply with Bulletin 85-03 or-from other experiences. A list of these conditions (including improper switch settings) is included'in Attachment A to this letter for-licensee review and information.

Response to Item g)

The deficiencies listed in Attachment A to the Generic Letter either have been or will be addressed by design basis reviews in. response 4

to Item (a) and/or the revised preventive maintenance programs 1(see response to Item (j)).

Item h)  !

i Each MOV failure and corrective action taken, including, repair, j alteration, analysis, test,.and surveillance, should be analyzed or justified and documented. 'The documentation should' include the results and history of each as-found deteriorated condition, malfunction, test, inspection, analysis, repair, or. alteration. All.

documentation should be retained and reported in accordance with plant requirements.

4 It is suggested that these MOV data be periodically examined (at' least every 2 years or after each refueling _ outage after program implementation) as part of a monitoring and feedback effort to-  !

establish trends of MOV operability. These trends could. provide the '

basis for a licensee revision of the testing: frequency-established to periodically verify the adequacy of MOV switch settings.(see items d. and_j.). For this monitoring and feedback effort, a_well R

structured and component-oriented' system'(e.g., the Nuclear Plant-Reliability Data System {NPRDS}) is needed to capture, track, and share the equipment history data. The NRC encourages the use of the ,

{

industry-wide NPRDS, appropriately modified, for this purpose in j view of the multiple uses for these data.

i

-Dockat Nos. 50-277

• ~S0-278 50-352 50-353 '

Response to Item h)

MOV failures are examined for root causes and reviewed for trends.

PECo has implemented failure analysis tracking systems. The computerized history and maintenance planning system (called CHAMPS) contains records of malfunctions, inspections, repairs-and modifications. Engineering reviews will be documented as part of the upgraded predictive / preventive maintenance program described in the response to Item (j).

PECo has an Operational Experience Assessment Program (OEAP) which >

disseminates information on events and discoveries at'many nuclear i

facilities, including those of PECo, to appropriate work' groups for-review. Recommended changes to PECo programs, procedures, and practices in response to these OEAP reviews are-identified, tracked and implemented as appropriate.

Information obtained from NPRDS is used to. identify similar failures when performing MOV failure analyses. .The CHAMPS Maintenance Request Form (work order for all power-plant maintenance activities) includes fields for NPRDS codes, which facilitates computerized searches of NPRDS reportable failures.

Docket'Nos. 50-277 50-278-50-352 50-353 Item 1)

Each licensee with an operating license (OL) should complete all design-basis reviews, analyses, verifications, tests, and inspections that have been instituted in order to comply with items

a. through h. within 5 years or three refueling outages of the date of this letter, whichever is later. Each licensee with a construction permit (CP) should complete these actions within 5 years of the date of this letter or before the OL is issued, whichever is later.

For plants with an OL, the documentation described.in items 1..and

2. below should be available within one-year or one refueling outage of the date of this letter, whichever is later. For-plants with a.

CP, the documentation outlined in items.l. and 2. should be available within one year of the date of this-letter or.before the OL is issued, whichever is later. The documents should includes.

1. The description and schedule for the design-basis review recommended in item a. (including guidance from item e.)

for all safety-related MOVs~and position-changeable MOVs as described, and

2. The program description and schedule for items b. through

h. for all safety related MOVs and position-changeable MOVS.

Response to Item i)

A description of the PECo MOV program consistent with-this; Generic Letter response will be prepared by October 31, 1990. .The schedule for the Generic Letter actions is-documented by this response.

Item j)

The d.,

program for the verification of the procedures outlined in item-as well as other tests or surveillance that the owner may' choose to use to identify potential MOV degradations or misadjustments, such as those described in Attachment A, should be implemented after maintenance or adjustment (including packing adjustment) of each MOV, and periodically thereafter. The-surveillance interval should be based on the licensee's evaluation of the safety importance of each MOV as well as its maintenance and performance history. The 4

.. i

.Dockst Nos.150-2777  !

?, -

'50-278 l 50-352 m 50-353' A

surveillance interval should not exceed 5 years or- three: refueling ,

out.

justifieages,d (see item h.)whichever for any isparticular longer, unless MOV.a-longer interval can be '

Response to Item i)-

t The use of diagnostics to monitor-operator performance following ,

1 corrective maintenance on MOVs is already an-integral part of the PECo maintenance-program. 'PECo has begun e'fforts to upgrade its;

~

~

predictive / preventive maintenance program for MOVs based on '

Reliability Centered Maintenance-principles. The. upgraded program

• i will incorporate the results of previous EQ equipment inspectionsJ s and the results of previous. diagnostic tests.- Failure' effects C evaluations and advanced diagnostic techniques will~be addressed.  ;

Based on the results of engineering' reviews, performance / predictive- o testing will be conducted at appropr~iate frequencies. These .

engineering reviews may justify-test intervals. greater than those- a r

recommended by Item (j)-for some MOVs. .W e expect this' program upgrade to be defined by October 31,.1990. Weiwilliprovide to the' NRC a program implementation schedule within 30 days.after  !

completion'of this program upgrade.

Item k) h f

In recognition of the necessity for preplanning, refueling' outages J that start within 6 months of thisiletter.need notcbe-counted!in establishing-the schedule to meet the' time' limits-recommended ~in-items 1. and j.

11

__.___._ir-E----- "

Dockot:Nos.' 50-277- i

.50-278i 4 -

• l 50-352 4 50-353 ,

Response to Item k) .

' No PECo refueling outages are scheduled to start within six~ months of the Generic letter issue date.

3 Item 1)

+

Each licensee shall advise the NRC'in writing within 6 months of the l date of this letter, that the above schedule and recommendations will be met. For any date-that'cannot.be met,Ethe licensee shallL advise the NRC of a revised schedule and provide a technical'-  !

justification in writing. For any" recommendation that it cannot. '

meet or proposes not to meet, .the licensee shall11nform the NRC and provide a~ technical justification, including ~any proposed-alternative action, in writing.

Each licensee shall also submit,11n writing, anyl future changes to, I scheduled commitments; for example, changes made on the basis of #

trending results (see itemsLh. and-j.). These revised schedules'or alternative actions may be. implemented without NRC approval.

Justification for the revised schedules and alternativetactions: '

should be retained on site. 4 Response to Item 1)

PECo will provide additional responses for Items-(c),.(j)c and (m).

l PECo will also notify the NRC of'any changes to commitments c described in this Generic Letter response;'however, PECo proposes not to provide further written notifications ofJchanges-that are t based on engineering reviews described in-the response to Itemi(j).

Information relative to changes wil'1 be readily availabld on-site for NRC review. ' Written notification for each changeLcould burden: -

PECo with preparation of frequent correspondence for minor changes, .

.l i

DockGt'Nos,=.50-277 50-278-50-352=  !

50-353' Item m)

Each licensee shall notify the NRC in writing within 30 days.after- '

the actions described in the first paragraph of item 1. have been completed.

Response to Item m)

PECo will notify the NRC within 30 days of completing the actions I described in our responses to Items (a) through (e). There are no further actions to be taken in response to Items-(f) through (h).

e