ML20101E695

Responds to 841029 Request for Addl Info Re Inservice Insp Program Concerning Proposed Second 120-month Interval Program.No Other Documents Available to Aid in NRC Review of Proposed Second 120-month Insp Program

ML20101E695
Person / Time
Site:	Peach Bottom
Issue date:	12/21/1984
From:	Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Stolz J Office of Nuclear Reactor Regulation
References
NUDOCS 8412260351
Download: ML20101E695 (16)

Text

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p PHILADELPHIA ELECTRIC COMPANY-L-

t 2301 MARKET STREET t-P.O. BOX 8699 PHILADELPHIA. PA.19101 SHIELDS L DALTROFF ale'r*.'ic",l5Emn.

December 21, 1984 Docket Nos. 50-277 50-278

'Mr. John F.

Stolz, Chief U.

S. Nuclear Regulatory Commission Operating Reactors Branch #4 Division of Licensing Washington, DC 20555

SUBJECT:

Peach Bottom Atomic Power Station, Units 2 and 3 NRC Request for Additional Information on the Peach Bottom ISI Program

REFERENCE:

Letter, J. F. Stolz (NRC) to E. G.

Bauer, Jr.,

(PECo.), dated October 29, 1984

Dear Mr. Stolz:

The reference letter forwarded requests for additional I SI information concerning the proposed second 120-month interval program for Peach Bottom Atomic Power Station Units 2 and 3, and certain exemptions associated with the first 120-month interval.

A delayed response to the requests was discussed with Mr. Gerald

'A. Gears, Peach Bottom NRC Project Manager, and found acceptable.

The requests for additional information are restated below along with our response.

REQUEST 1.

-By letter dated June 28, 1984, you submitted a proposed Inservice Inspection (ISI) program for the second 10-year inspection interval of Peach Bottom, Units 2 and 3.

We will be using this program, along with the documents referenced in it, to review your requests for relief and code-allowed exemptions from the requirements of the 1980 edition (with addenda through Winter 1981) of Section XI of the ASME Boiler and Pressure Vessel Code.

If there are any documents not j

referenced that you believe may aid our review gg 8412260351 841221 PDR.ADOCK 05000277 G

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, - Mr'.1 John F.JStolz1 December 21,.1984 Page 2-

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(including any additional relief requests),

- please provide us with copies.- If they have been previously furnished.tx) -the? NRC, please document turreference.

vi.

PECo RESPONSE 4

.There are no other documents that can be_ identified at this

> time:which'would aid inJNRC' review ofLthe proposed second

-120 month in'spection. program for Peach Bottom Units l 2 and 3..

REQUEST.

-2.

. Referring back to' the first 10-year inspection interval,'if,there are anysinstances where you have previously-not requested relief in the.

submittals reviewed-for the-Safety Evaluation

- Report, you must request such relief, under the terms of subparagraph 10 CFR 50.55a (g) (5) (iv),

~ from the requirements of the Code edition

. applicable during the first. interval.

Please submit such requests, if any, at this time.

PECo RESPONSE T'.. _

At this' time,. Philadelphia Electric Company requests, pursuant to - Section 50.12 of the Commission's regulations,.

an exemption from performing.the following Inservice-s

Inspection provisions of 10 CFR 50.55a(g) during the first 120-month interval forLPeach Bottom, Unit 3.

1.0 Request for Relief

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1.1 Component Class II Emergency. Core Cooling System (ECCS)

Components and Piping Previously Exempt Under IWC-1220(c).

1.2 Requirement from Which Relief Requested i

Schedule relief under the first 10 year ISI program for inspection of ECCS components and piping in accordance with IWC-1220 (c).

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Mr.-John;F.,Stolz Decembar_ 21, 1984 Page.3

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-1.3 Justification

_There is'not sufficient time' remaining in the current ISI interval to complete. the inspection of the. subject components and piping, particularly portions.of-the RHR,' Core Spray, and-HPCI systems. _The~following. work must be performed prior _to the actual required examinations.

1.

An examination plan must be developed which includes the physical identification of all pipe welds and components..

2.

Erection of a significant amount of scaffolding.

3.

Upon gaining access to the piping, the weld crowns require significant rework, since the weld configurations are not conducive to Ultrasonic Testing.

O By letter dated May 2, 1983, J.

F.

Stolz, USNRC, to E.

G. Bauer, Jr., PEco, transmitting the Safety Evaluation -Report'-for the first 10-year program, the NRC. staff concluded that these examinations should be included and denied the relief request for the current interval.

At the time of receipt of this letter, Peach Bottom Unit.3 was undergoing inspections of primary system piping in accordance with IE Bulletin 33-02 and there was not sufficient time to develop the inspection plan for ECCS components necessary to satisfy Code requirements.

1.4 Testing in Lieu of Section XI Requirements We are proposing a schedule to complete inspections on Class II ECCS components and piping previously exempted under Article IWC-1220 (c) of Section XI of the ASME Code.

Since five refueling outages have been completed during the current 120-month ISI interval for Unit 3, Philadelphia Electric Company proposes to examine a minimum 1/6 of the total number of subject components and pipe welds required for

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LMr.\\JohnLF.'Stolz

~Decsmbarl 21,[1984 Page 4.

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examination during the current interval during

.the;next' refueling outage.. This is. based onisix

. inspection periods per.120-month.ISI interval.

This plan would: carry'through into.the'next 120-t month ISI~ interval to' ensure'that.all ECCS

. component inspections ~are completed during~that

. interval.

. A similar relief.. request for Peach Bottom Unit 2 3 -

was forwardedito the NRC,.S. L. Daltroff,.PECo, letter.to J. F. Stolz, USNRC, December-27, 1983, and found'to be acceptable.in-the NRC response from G. W..Rivenback, USNRC, to E. G. Bauer, Jr.,

.PECo,tletter dated-June 1, 1984.

-2. 0.. Request for Relief 2.1 ' Components

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Reactor recirculation pumps for Paach Bottom Unit -

3 2AP34 & 2DP34, : ASME Class 1 (equivalent) 2.2' : Requirements f rom which Relief Requested Table IWB-2500-1, Categories B-L-2 and B-M-2,

-require visual examination of the internal

-pressure boundary surfaces of one pump in each group of pumps of similar function to be performed once per inspection interval.

2.; 3 Justification The disassembly of a recirculation pump'during the current 120-month interval for the sole purpose of visually inspecting its internal surfaces would result in unnecessary personnel exposure,. potential hazards, generation of excessively high amounts of radioactive waste and would be in conflict with the concept, " As Low As Reasonably Achievable."

There has been no maintenance required on these pumps during the first ten year interval which would have accommodated visual inspection.

As a result of an extensive outage currently in progress on Peach Bottom Unit 2 for replacement of primary

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Decembsr.21,;1984; Page 5,

--system p'iping, identical pumps were disassembled

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1and inspected.. During..this inspection no

_ a reportable-indications were discovered.

Thus, it

,is. appropriate ~to' postpone inspection of the Unit 3 pumps'until the second'120 month ISI1 interval.

1

. 2.4: Testing in Lieu-of Section XI= Requlrements =

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' As an' alternative inspection, a:UT. wall thickness

' surveillance program to verify structural

integrity-shall~be-incorporated _into the upgraded

- ISI program zto. be performed at or near the beginningfoffthe next 120-month interval.

The following. testing,shall continue to be implemented.on the recirculation pumps to assure

' structural integrity:

.l.-

Hydrostatic 1 pressure tests and leak tests performed periodically.

'2.

. External visual inspections performed during seal maintenance.

-3.

. Continuous vibration monitoring.

.4.

Continuous drywell leakage monitoring.

5.

Visual ~ inspection of internal surfaces upon

-pump disassembly for maintenance.

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. 3.0 Request for Relief 3.1 Components t

g, EASME Class 1 (equivalent) valves exceeding 4-

inches nominal pipe size for Peach Bottom Unit 3.

(Recirculation suction, discharge valves and equalizing valves)

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3.2.. Requirement from which Relief Requested J

Table =IWB-2500, L Category B-M-2,.and Table LIWB-2600,11 tem'B 6.7Erequire visual; examination of-.

the-internal ~ pressure boundary-surfaces of-one'

valve in~each. group of valves of the same. design,

manufacturing method,_ manufacturer, and function to be performed once per inspection interval.

3.3-LJustification-11n orderito carryLout these inspections, it would be'necessary:to disassemble these. valves during

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the. remainder of the current 120-month interval.

Thus it would be. impractical due to time limitation, potentialLsafety hazards, and

-excessive radiation and contamination exposures.

-Also,.a large scope of preliminary work which must be performed (i.e.,foff' loading fuel elements, draining the reactor vessel,. plugging L

the jet pump risers)- : Consequently, it would be

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more appropriate to coordinate these inspections with other-activities that would require a similar configuration'of the NSSS to minimize decontamination and radiation exposures.

We request that relief be granted under the first

-interval ISI program and commit to.the inspection of the subject valves.upon valve disassembly for "S

maintenance during the next-120-month interval.

There has been no maintenance required on_these valves during the first ten year interval which would have permitted-visual inspection.to be performed.

As with the request for relief from examination of the reactor recirculation pump internals, access to identical valves became available.and the visual inepection was performed on the Unit 2 valves.

During that inspection no flaws requiring repair were discovered.

Thus, there exists a high degree of confidence that inspection of-the Unit 3 valves can be appropriately postponed until the second 120-month ISI. interval.

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Mr. JohnfF. Stolz December 21', 1984

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4 3.4 Testing in Lieu of 'Section XI -Requirements-3 w.

As an4 alternative ~ inspection, a UT wall thickness

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surveillance 1 program to verify: structural-l integrity 1shall= incorporated into the upgraded.

s ISI p program.

The following-testing:shall. continue to-be implemented on the subject valves tx) assure structrural: integrity:

1.

Hydrostatic ~ pressure testing and leak tests performed periodically.

2.-

Continuous drywell-leakage monitoring.

3..

Visual inspection of internal surfaces upon valve: disassembly for maintenance.

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REQUEST'

-3.

Section 2.2.2 of the Program 1(p 2-5)

This;section, lists.three' areas of Class 1 piping.

Ln which it may be impossible to obtain complete

' volumetric examinations on-some welds.

These areas'are described below:

AEeas'within tha containment penetrations,

.a.-

'b.

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Cast fittings and structures that are not amenable to UT examination or-in a system

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that cannot be drained without draining the LRPV, and

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c.

Any weld that, during the preservice examination (PSI), was.found unsuitable for 3

UT examination (and continous evaluation indicates that the state-of-the-art techniques'do not allow UT examination) and that cannot be radiographed due to (1) geometry and/or interference from surrounding' structures or (2) the system cannot be drained without draining the RPV.

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'Mr. John 5F. Stolz:

December:21,11984!

Page'8 L

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s IFor those welds that;are1known to:present1 1 -

limitations - to examination - (such :as those L inside -

containment ~ penetrations), please' provide-

-specific relief-requests.-

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' PECo. RESPONSE-V

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^ Philadelphia Electric Company will provide.. specific relief'

, request for.these_ Class'l piping welds by, January 31, 1985.

+J JREQUEST 4.

' Subsection'IWE of the Code w

The above referenced edition-of the Code.contains airecently11ssued subsection (IWE) pertaining to containment related examinations.

The Peach Bottom-program plan, however, contains no

provisions

for examinations under-subsection-IWE.

Pleasefprovide a program for-examining the areas

, subject-toithis subsection.

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'PECo RESP'ONSE

In accordance with Federal Register 48 FR 5532, effective

-March'9, 1983 Statements of Consideration,'the second 120-

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month ISI' program need not address subsection IWE of the L

code.1 48,FR 5532 incorporates, by reference, the Winter

-1981 Addenda' to = the' 1980 Edition of-Section XI of the ASME Code in 10LCFR 50.55a.

However, one of the changes affected

'by the Rule fin. 48.-FR 5532 states, in part, "The regulation does not currently ' address the ISI of containments.

Since

this amendment is onlyfintended-to update current' regulatory requirements tx) include : latest Code Addenda, the requirements of Subsection IWE are not imposed upon

-Commission licensees by this amendment."

100FR50.55a

. presently'only incorporates those portions of Section XI

. that address the ISI requirements for Class 1, 2, and 3 components and their supports.

Since 'the second 120-month ISI program will be performed in Laccordance with Lthe ~1980 Edition through Winter 1981 Addenda of Section XI of the ASME code, Subsection IWE for containment-related examinations is not required for Peach Bottom Units 2 and 3.

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Mr.7 John.'F. : Stolz.

December 21,

1984 Page 9 4

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i REQUEST-5.

' 2.4.1 Request for : Relief' on Reactor Vessel Welds - (p 2-10)

-(a)

Please provideLinformation on the.

. accessibility of reactor vessel welds to examination ~from the vessel interior.

-(b)- What percentage of each ' beltline

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' longitudinal and circumferential weld'is estimated to be accessible from the vessel' exterior?

PECo RESPONSE

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'(a) '

.-The'shell welds' required to be examined in accordance

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'with'the 1980-Edition of the Code in the reactor beltline-region below the feedwater nozzles are not

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. accessible from the interior: of the vessel.-

Further, all baseline UT examinations of vessel welds were performed from the. vessel exterior.

Since the interior vessel'shell walls are clad with 316-Stainless Steel. Cladding the shell welds are realistically inaccessible from the vessel interior.

(b)

It is estimated that between 5 and 15 percent of the

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longitudinal and circumferential welds are typically accessible from the vessel exterior, which is in.

accordance with the 1974 Edition through Summer 1975

' addenda of-Code Section XI requirements.

' REQUEST 6.

2.4.4 Relief Request on Class 1 System Hydrostatic Testing-(p 2-13)

(a)

Please show why the relief valves of lowest setting cannot be gagged shut for performance of hydrostatic. tests.

(b)

The relief request states that removing the relief valves is impractical.

We note, however, that the valves are bench-tested when lift tests are required.

Please show why a code hydrostatic test cannot be performed when the lowest-set relief valves are removed for bench testing.

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.Decambar 21, 1984 d[

'Page 10' iPECo' RESPONSE' A

-(a)'

The~ availability of anc ppropriate. relief valve gag.is a

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being pursued with the manufacturer, Target Rock

, Corporation.-. e will contact Target : Rock ' Corporation, W

Lby way;ofla letter, to seek.their. advice and assistance'to determine if,the relief. valves can be fsafelysgagged.

This correspondence willLbe completed lur. January 7, 1985, and we will advise the Commission 1

by' February 1,:1985, of the results of this-Linvestigation.

' (b).

The Peach Bottom, Technical Specifications require primary ~ containment integrity to be maintained whenever reactor water temperature is above 212

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degreesiF and; fuel;is in the. vessel..Since the

' hydrostatic' test boundary extends beyond the-primary

. containment boundary, the hydrostatic. test temperature 4

is limited to-- 212 degrees F.

ThisLcorresponds to a test pressure of 1082.psig on Table INB-5220-1 of 1980 ASME Boiler;& PV Section XI..This pressure is unacceptably close. to the installed RV -settings of 1105 psi L (+ 11~ psi) and 1115 ' psi

(+ ll. psi).

We

-' propose to conduct the hydrostatic test with the relief' valves in place at a test' pressure of 30 psig

~below thes lowest. actual relief valve setting.

The

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lowest actual relief valve setting will be determined JR

'from the latest available bench test data.

We believe that this-method is acceptable for the following reasons:-

s The purpose of -the : hydrostatic test is to verify primary; coolant boundary integrity.

Performing the test with portions of the primary boundary removed (relief valves) lessens our assurance of that integrity.

Performing the hydrostatic test with the relief valves in place has enabled us to detect potential malfunctions.

Primary boundary valve to pipe flange leaks and premature relief valves " lifting" can be identified for correction to prevent the consequences of.these malfunctions during power operations.

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. Half of the relief valves are removed from each

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refueling outage for bench testing.

They are installed prior to performing the hydrostatic tect.

since a safe gaging device is not available, four or m

more relief valves would have to be removed just to

. perform the test.

The radiation dose incurred due to

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Mr. J J2 hn ' ' F. Stolzi December - _21,.1984 Page 11 b

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Lthis: additionalTremova1 and reinstallation activity 'is 115' man-Rem,'and'is-contrary to' good ALARA practices.

The': reinstallation of'the. relief valves would require-80 hoursTto' complete and_have to be performed on m,

critical path..

The[ difference between the~codeltest pressure (1082' s.

psig) and:the proposed test pressure-(30 psi'g less

-P.hanT1owest' relief 1 valve sections) is nominally 12 to

'18 psig.- This-pressure differential will-not; significantly,effect any leakage. rate or our ability

.to detect.it..

JREQUEST.

7.-

4.4.1 Relief Requesti on Pressure

? Testing of Class 3 Systems -(o 4-3)'

Alccording'to the Code edition referenced above,-

Class 13 systems are to be hydrostatically tested to 110% of the setpoint of the lowest-set relief valve that protects the system or portion ofnthe system.: This7 pressure is considerably less than

'110% of; design. pressure.

Please submit a revised reliefirequest based on the capabilities of-the various pumps to produce the required pressures.

Those sections of each system that actually need.

relief should-be specified.

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PECo RESPONSE-

-Thelfollowing table lists the pump shutoff' head, the lowest-set relief valve setting and the-1980 Code required test

. pressure for each Class 3 system.

System Pump

. Lowest-Set 110% of Psv

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System Shutoff Head Relie f. Valve (Psv) 1980 Code-Test Pressure HPSW 430 PSI 450 PSI 495 PSI (high' pressure

.' service water).

ESW -

65 PSI 125 PSI 137.5 PSI

-(emergencyL _

Lservice water)_

ECS 65 PSI 125 PSI 137.5 PSI The table demonstrates that testing these systems to 110% of Lthe lowest-set relief valve wetting (Psv) is beyond the

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Mr.'J hn'F. Stolz Dec:mber.21, 1984 Page 12 ca'pability ofLthe system pumps and therefore would' require the use of a special hydrostatic test pump.

i Since valve leak' tightness is not a requirement.for these Class'3-systems, considerable effort would be. required.to

.make-the valves sufficiently leak tight to match-the inflow.

capability of.the hydrostatic test pump. -The maximum capacity'of.the hydrostatic test pump,is limited'by the available 3/4 and 1" pipe connections.

Consequently,,

testing at pressures required by the Code is not feasible.

-Further, the proposed hydrostatic test pressures are significantly higher than the. maximum pressures generated by the system-pumps (shutoff haad)-and therefore provides a

valid verification'of system integrity.

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6i LMr. J hnlF.fStolz December 21,;1984' Page113 Y

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REQUEST-.

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~ 5.3.1 Relief Request on'ISI of.

_ Component Supports (p 5-1) 4

. Apparently,.the requested relief is intended to eliminate-duplication ofl examination.and-l.

reporting activities between' Code requirements, and.your Technical Specifications.

Please submit i

' a-revised. relief. request that shows how the.

componentisupport. program. authorized in the.

Technical Specifications meets or exceeds the

- requirements of;the Code.

Alternatively,1you may wish to: propose a change in the Technical Specifications eliminating the component' support

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- program.

Such~a request would be in' line with

' NRC-guidance, which recommends changes in the Technical. Specifications to eliminate conflicts with the Code.

PECo RESPONSE The following _provides additional justification for relief from.the. requirements of Table IWF-2500-1, Category F-C, Item: 3.50 of.Section XI, of the 1980 Ed

• tion of the ASME Code and reflects.the surveillance requirements for hydraulic and mechanical snubbers in:the current Peach Bottom-Technical Specifications.

The current technical specifications for snubber

surveillance conform to NRC requirements contained in a F

generic letter from D. G. Eisenhut, USNRC, to all licensees-

. dated-NovemberL20, 1980.

These Technical Specifications were: approved int the Commission.as Amendment Nos. 101 and 103 to the1 Peach Bottom Technical Specifications as of July 2, 1984.

-Snubbers on Class.I, Class 2 and Class 3 piping systems, 1 ;.

pumps and valves are demonstrated operable by performance of

.the following inspection program specified in Section 4.11.D (pages:234a through 234e) of the Technical Specifications.

Visual Inspection.

All~ snubbers on safety related systems are visually inspected during normal 18-month fuel cycles for Peach Bottom Units 2 and 3.

IIowever, when snubbers fail the visual inspection the inspection schedule is increased as follows.

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N Mr. ? John F.: Stolz: '

December 21,'1984

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Noa'of. Snubbers ~

Next Visual-Found1 Inoperable Inspection-

--During : Inspection Period' Period R

0' 18 mo. +-25%

1 12 mo. I 254 2

6 mo. I 25%

L3,4 4 mo. I 25%

f5,6,7:

2 mo. T 25%

8 or more 1 mo. [ 25%

1The required' inspection interval is not lengthened

'more than.one step at a time.

' The visual inspection verifies that (1) there-are not indications of damage or impaired operability,. (2) 4 attachments are secure, and -(3) there.is freedom of.

. movement if this can be verified without. disconnecting the snubber.

When th'e. fluid. port of a hydraulic snubber is found to

'be uncovered,.the snubber.shall-be. determined to be inoperable for,the purpose of establishing the next visual inspection interval.

Functional ~ Testing-Once'each' operating cycle, during shutdown,.a

' representative sample of 10% of each type of

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(mechanical or hydraulic) snubber.is functionally tested :in place or in a bench test.

For every unit found to be inoperable, an' additional 10% of-that type of snubber is functionally tested until no more failures are found or all. snubbers.of that type have been tested.

s The representative sample selected for functional testing includes various configurations, operating

. environments, sizes, and capacities of snubbers.

At least 25 % of.the sample includes snubbers from the following categories:

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Mr.--J;hn F.JSt31C Doctrbar 21,. 1984 Page 15 u

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1. -

_The.first' snubber away from each reactor nozzle.

- 2..

Snubbers within five feet of heavy equipment-

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'(valves, pumps, turbines, motors).

13.'

Snubbers connected to safety / relief valve discharge piping within 10-feet of the valve.

If any snubber selected for functional test either fails to lock up or fails to move, the cause'shall be evaluated and(if the failure is caused by.

manufacturing or design deficiency, all snubbers of the~same design subject to the same. defect shall be functionally tested.

This testing. requirement is independent of the requirements above for snubbers not meeting the functional test acceptance critoria.

In addition to the' regular sample, snubbers which failed the previous functional test shall be retested during the next testing cycle.

If a failed snubber was replaced, both the replacement snubber and the repaired snubber (if it had been repaired and installed in another position) shall be retested.

-The Functional Test Criteria for hydraulic snubbers

-verify that:

a)

Restraining action is achieved within specified range of velocity or acceleration in both compression and tension.

g b)

Snubber bleed rat e is within the specified range in both tension and compression.

Snubbers specifically rquired not to displace under continuous load have this capability verified.

'The Functional Test Criteria for mect.anical snubbers verify that:

a)

The force that initiates free movement of the snubber rod in either tension or compression is less than the specified maximum drag force.

Drag force shll not have increased more than 50% since the last functional test.

b)

Restraining Action is achieved within the specified range of velocity or acceleration in both tension and compression.

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Mr."Jchn F.'EStols' December-21,.1984 Page' 16

= c) -

. snubber release rate, where required, is within

. the'specified-range-in: compression or tension.

4 i Snubbers specifically required not1to displace

.un er continuous-load have this capability d

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verified.

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.The visual inspection _ frequency for snubbers on Class.

l 2, and 3 systems-as specified in:.the Technical-i Specifications-is in accordance with TableLIWF-2500-1, 4

Category-F-C,. Item F.3.50.

The functional test

-requirements for mechanical and hydraulic snubbers provide. additional assurance that the snubbers function-as designed under various loading conditions.

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-If any further information-ic~ required to complete your review, please do not hesitate to contact us.

Very truly yours, 7

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J. H. Williams, Resident Inspector l

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