ML20033E016

Technical Evaluation Rept on Response from Philadephia Electric Co to Generic Ltr 88-01 Pertaining to Peach Bottom Atomic Power Station,Unit 2

ML20033E016
Person / Time
Site:	Peach Bottom
Issue date:	09/30/1989
From:	Bates R, Lakner A VIKING SYSTEMS INTERNATIONAL
To:	NRC
Shared Package
ML20033E015	List: ML20033E014 ML20033E016 ML20033H021 ML20033H023
References
CON-NRC-03-87-028, CON-NRC-3-87-28 GL-88-01, GL-88-1, NUDOCS 8909270090
Download: ML20033E016 (28)

Text

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h ATTACHMENT 1 i

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i TECHNICAL EVALUATION REPORT ON flh

/f RESPONSE FRON 1

PHILADELPHIA EUKTTRIC OCMPANY 70 CENERIC IEITER 88-01 PERTAINING TO THE j

I PEACH BOTION ATONIC POWER STATION { WIT 2 j ~

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Published September, 1989 J

l prepared by l

l Robert C. Bates i

Armand lakner

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r Viking Systems International 2070 Wm. Pitt Way 8/,

i Pittsburgh, PA l

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Prepared fort U.S. Nuclear Regulatory Commission Washington, D. C.40555 under I

Contract No. NRC-03-87-028 Task Order 005 i

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g ABST1 TACT j

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This report contains an evaluation of the licensee (Philadelphia I

Electric) submittal for Peach Bottos Atomic Power Station, Unit 2 which i

was submitted in response to the NRC Generic Intter 88 41 in which j

Philadelphia Electric was requested to (1) Purnish their currest plans relating to piping replacement and other measures to sitigate IGS00, inspection, repair, and leakage detection.

(2) Indicate whether they plan to follow the NRC Staff positions, or propose alternative measures, f

Philadelphia Electric's plans are evaluated in Section 2 of this report f

in terms of compliance to NRC Staff positions. Philadelphia Electric f

presented an alternative position concerning a change to the Technical Specification on ISI which is evaluated in Section 3 of this report.

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St#HARY

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The Licensee. Philadelphia Electric, submitted a response to the NRC Ceneric Letter 88-01. Philadelphia Electric's response pertaining j

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to the austenitic stainless steel piping in the Peach Bottom Atomic Power Station Unit 2 (a BWR nuclear power plant) was evalmeted in l

terms of: (1) Their previous and planned actions to sitigate 10500 l

l to provide assurance of continued long-tore service.

(2) noir l

j Inservice Inspection (ISI) Program. (3) Their Technical Specifications l

l pertaining to ISI and their plans to ensure that leakage detection i

will be in conforsance with the NRC Staff position. (4) heir plans to notify the NRC of significant flaws identified (or changes in the l

condition of the welds previously known to be cracked) during inspection

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j and evaluation of such flaws.

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Philadelphia Electric endorses nine of the 13 NRC Staff positions which are outlined in Generic Letter 88-01. They did not indicate endorsement or rejection of four of the NRC Staff positions (i.e., clasping devices, veld overlays, stress improvement of cracked weldoents, and water j

i chemistry). They do use controlled water chemistry.

It probably does r

not include HWC, but their submittal is not clear on this ites.

Extensive programs of piping replacement have been conducted at Peach Bottom 2 so that most welds (375 out of 484) are IGSOC Category A.

but 100 of the remaining 103 are IGSCC Category G welds.

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They consider that RWCU welds outside of containment are uninspectable.

Otherwise, an inspection program proposed for Peach Botton 2 conforms with the NRC Staff positions on schedule although the specific welds scheduled for inspection were not identified. Some uncertainty exists concerning their position on inspection methods and personnel.

4 Philadelphia Electric declined to amend the Technical Specification on ISI to include a statement in the Technical Specification that the i

ISI program will comply with the NRC Staff position. Rather they proposed to include such a statement in the ISI program document.

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CONTENTS 1

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ABSTRACT i

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SUMHARY I

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1. INTRODUCTION i

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2. EVALUATION OF RESPONSE 10 GENERIC 121TER 86-01 i

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i 2.1 Documents Evaluated i

l 2.2 Review of Philadelphia Electric's Responses to Staff 3

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Positions and Implementation of Those Positions i

2.3 Review of Classification of Welds. Previous 4

Mitigating Actions, and Previous Inspections 4

2.3.1 Current IGSCC Classifications i

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2.3.2 Previous Mitigating Treatments i

2.3.3 Welds Excluded from Scope of Generic Letter 88-01 8

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1 10 2.3.4 Previous Inspection Progras 2.3.5 Evaluation of Previous Mitigating l

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Actions and Inspections t

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f 10 2.4 Current Plans for Mitigating Actions Il 2.4.1 Summary of Plans 11 2.4.2 Water Chemistry Control I

2.4.3 Evaluation of Conformance to Staff r

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Positions and Recommendation l

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2.5 Plans for Future Inspections 2.5.1 Summary of Inspection Schedules 12 l

2.5.2 Personnel and Nethods 12 13 l

2.5.3 Sample Espansion 2.5.4 Plans for bainspectable Welds 13 I

2.5.5 Evaluation and Recommendations 14 i

i 2.6 Changes in the Technical specification 15 j

Concerning ISI i

j 2.7 Confirmation of Leak Detection 15 in the Technical Specification l

2.7.1 Philadelphia Electric's Position 16 2.7.2 Evaluation and Recommendation 17 1

t 2.8 Plans for Notification of the NRC of Flavs 18 2.8.1 Philadelphia Electric's Position 18 2.8.2 Evaluation and Recommendation 18 I

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3. ALTERNATIVE POSITION......................

1 3.1 Changes in the Technical Specification 19 Concerning ISI 3.1.1 Philadelphf* Electric's Position 19 3.1.2 Evaluation and Recommendation 20

4. CONCLUSIONS AND RECOMENDATIONS 20 1

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5. REFERENCES G

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1. INTRODUCTION Intergranular stress corrosion cracking (IGSOC) near voldoents in 5o111u3 Vater Reactor (BWR) piping has been occurring for almost 20 years.

Substantial efforts in research and development have been sponsored by the BVR Owners Group for ICSCC Research, and the results of this progras, along with other related work by vendors, consulting firms and confirmatory research sponsored by the NRC, have permitted the development of WRC Staff positions regarding the IGSOC problems. The technical basis for NRC Staff positions is detailed in Reference 1, and further background is provided in Reference 2.

The results of these research and development programs prompted the NRC to issue Generic 14tter 88-01 (see Reference 3) requesting all licensees of BVR's and holders of construction permits tos (1) Furnish their current plans relating to piping replacement, inspection, repair, and leakage detection.

(2) Indicate whether they:

(a) Plan to follow the staff positions, or (b) Propose alternative measures, j

Specifically, Generic Letter 88-01 stated that an acceptable licensee response would include the following items:

(1) Current plans regarding pipe replacement and/or other measures taken or to be taken to mitigate IGSCC and provide assurance of continued long-term piping integrity and reliability.

I (2) An intervice inspection (ISI) program to be implemented at the 4

next refueling outage for austenitic stainless steel piping.

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(3) A change to the Technical Specifications to include a statement j

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in the section on ISI that the inservice inspection progren for piping will be in conforesace with the staff positions on

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schedule, methods and personnel, and sample expansion.

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(4) Confirmation of plans to ensure that the Technical Specification f

5 related to leakage detection will be in conforanace with the j

f Staff position on leak detection.

i (5) Plans to notify the NRC, in accordance with 10CPR50.55a(o),

l of any flaws identified that do not meet 1 4 3500 crite'ria of f

Section II of the ASME Code for continued operation without j

evaluation, or a change found in the condition of r.he welds i

I previously known to be cracked, and an evaluation.of the flaws for continued used operation and/or repair plans, i

This report contains a technical evaluation of the response which Philadelphia Electric (somettoes called PE in this report) submitted l

l in response to the NRC Generic Letter 88-01 pertaining to the Peach 7

l Bottom Atomic Power Station, Unit 2 (hereafter called Peach Botton 2).

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2. EVALUATION OF RESPONSE TO CENERIC LETTER 88-01 j

i This evaluation consisted of a review of the response to NRC Generic Letter 8B-01 of January 25, 1988 by Philadelphia Electric pertaining l

l to Peach Bottom 2 to determine if their performance and plans are in i

l conforn.ance with the NRC Staff positions or if proposed siternatives are acceptable. Proposed inspection schedules and a.aendments to the l

l Technical Specification were included in the review.

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2.1 Documents Evaluated Review was conducted on the information pertaining to Peach Botton l

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j 2 provided by the Licensee in the following documents.

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(1) " Response to Generic Letter 88-01, 'NRC Posities on IGS00

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in BWR Austenitic Stainless Steel Piping' for Peach Bottom

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Atomic Power Station," Docket Nos. W277 and h278, I

Philadelphia Electric Company, 2301 Market Street, P.O.

l Bos 8699, Philadelphia, PA 19101 August 2, 1988.

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(2) " Peach Botton Atomic Power Station, timits 2 and 3 Revised I

l Response to Generic latter 88-01, 'NRC Position on IGS00 l

i in BWR Austenttic Stainless Steel Piping '" Docket Nos.

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S277 e.nd 50-278, Philadelphia Electric Company, 2301 Market 1

Street, P.O. Box 8699, Philadelphia, PA 19101, March 31, l

1989.

l Hereafter, in this report, these documents will be referred to as j

Philadelphia Electric Submittals No. 1 and No. 2 respectively, j

and collectively as the Philadelphia Electric Submittals.

2.2 Review of Philadelphia Electric's Responses to Staff Positions t

l and Implementation of These Positions.

l Gentric Letter 88-01 outlines 13 NRC Staff positions pertaining to (1) saterials (2) processes. (3) water chemistry. (4) weld overlay, (5) partial replacement (6) stress improvement of

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j cracked weldsents (7) clasping devices, (8) crack evaluation and repair criteria, (9) inspection methods and personnel, (10)

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inspection schedules, (11) sample expansion, (12) leak detection, and (13) reporting requirements. Generic Letter 88-01 states i

that the licensee should indicate in their submittal whether they endorse these NRC Staff positions or propose alternative i

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positions. The Philadelphia Electric Submittal did not specifically state acceptance or rejection of the 13 NRC Staff

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positions, but the Philadelphia Electric positions en most of the 13 items were implied in dioevestens in the Philadelphia Electric Submittels, h oe positions are pretented in Table 1.

Note that Philadelphia Electric indicated acceptance of mine of the thirteen NRC Staff positions. Concerning processes:

they indicated that solution treatina has been used for some velds in replaconent piping, they did not indicate whether they endorse heat sink welding, and they stated that they prefer to use partial replacement rather than stress improvement for sitigating IGSOC. ' Philadelphia Electric did not indicate either endorsement or rejection of the NRC positions on the use of Hydrogen Vater Chemistry, Weld Overlay, Stress Improvement of Cracked Weldsents, or Clasping Devices. In addition, although they indicated that they endorse the NRC Staff position concerning inspection schedules, they did not supply actual schedules for either past or planned inspections. Concerning water chemistry: Philadelphia Electric stated that they use controlled water chemistry, but so far as could be determined from the Philadelphia Electric Submittals, this does not involve Hydrogen Vater Cheatstry.

I 2.3 Review of Classification of Welds. Previous Mittaatina Actions. and Previous Inspectio g l

l 2.3.1 Current ICSCC Classifications-i Table 2 provides a summary of the classifications of welds at Peach Botton 2 into the various ICSOC categories on a l

systes-by-systes basis. ICSOC classifications of the welds are also contained on a weld-by-weld basis in the Philadelphia Electric Submittal, but they are not reproduced in this 4

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i Table 1 j

L, Summary of PE's Responses to Staff Posittens

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l PE Accepts WRC Applied Consider for Staff Position Staff Positip In feet Future Use j

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1. Materials yes yes yes yes(*)

yes(*)

yes(*)

2. Processes II)

NI(b)

II)

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3. Vater Chemistry NI

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4. Veld Overley NI no NI f

5. Partial Replacement yes yes yes l

6. Stress Improvement of Cracked Veldsents NI no no i

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7. Clamping Devices NI no NI i,

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8. Crack Evaluation and l

j Repair Criteria yes no yes

9. Inspection Method and Personnel yes yes yes

10. Inspection Schedule yes(c) gy 7,,(c)

11. Sample Expansion yes NI yes

12. Leak Detection yes yes yes

13. Reporting Requirements yes yes (a) Solution heat treatment of some velds in repiscenent piping was applied. Stress improvement has not been used and is not planned for future use. No indication was provided whether heat sink welding q

has been or will be used.

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I (b) Vater chemistry control applied, but so far as it is possible to determine from the Philadelphia Electric Submittels, it does not include HWC.

(c) Neither previous nor planned inspection schedules and results were submitted, but PE stated that schedules would comply with NRC Staff 4

position.

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i Table 2 i

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l Summary of ICSOC Classification of Wolde in Peach Botton 2 Number of Welds of Indicated ICSOC Catenorr j

Syst ej A_

B C

D l

F G

.IRitli j

Rectre.

132 0

0 1

0 0

3 136 i

RRR 119 0

0 0

0 0

0 119 C.S.

100 0

0 2

0 0

2 104 j

RWCU-1 21 0

0 0

0 0

0 21 RWCU-2 1

0 0

0 0

0 95 96

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RPV-JPI 2

0 0

0 0

0 0

2 l

RPV-No:

0 0

0 0

0 0

6 6

Totals 375 0

0 3

0 0

100 484 j

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Explanation of abbreviationst Recire. - Reactor Recirculation (includes nozzles N1 and N2)

RER

- Residual Heat Removal C.S.

- Core Spray (includes nozzle N5) i RWCU Reactor Water Cleanup from RHR to outer containment toolation valve RWCV Reactor Water Cleanup beyond outer containment isolation valve RPV

- Reactor Pressure Yessel r

JPI

- Jet Pump Instrumentation Noz

- Nozzles r

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. report. Note that in most of the piping systems (the f

exception being the piping that is outboard of the containment f

l 1 solation salve in the Reactor Water Cleanup system) only f

a few ICSOC Category D and IGSOC Category G welds exist.

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and all other velds in those systems are IGSOC Category A l

l welds. However, almost all of the welds in the piping that l

1s outboard of the containment isolation valve in the Reactor Water Cleanup are IGSOC Category G welds.

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f Philadelphia Electric Submittal No. I states the following l

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concerning the IGSCC classifications of certain of the RWCU 1

and Core Spray welds:

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f "The selection of NRC Generic 14tter 86-01 IGSOC

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categories resulted from thoroughly researching currently f

l available documentation containing piping and welding l

l characteristics applicable to ICSOC resistance."

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"The information necessary to determine IGSOC resistance j

l has been partially indeterminable for a limited number j

i of cases (e.g. delta ferrite AS7M A262-A testing, etc.).

i IGSCC categories for these welds have been selected by

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j comparing characteristics of similar velds of known l

composition, applying typical or average characteristics to known materials, and performing a metallurgical assessment from experience obtained through the pipe l

l replacement effort."

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f 2.3.2 Previous Mitimatina Treatments i

Philadelphia Electric has chosen to apply piping replacement as the preferred method of mitigating IGSCC rather than l

applying stress improvement treatments. The large number of IGSCC Category A welds is the result of extensive piping i

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replacement programs, heee pipias replacement programs f

l are summarised in Table 3 of this report.

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I In Table 3, certain sections of the RWCU piping are designated as Section A, Section 3, and Section C.

heee sections

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include piping as follows:

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i Section A includes piping from the connection at the l

j RHR pump suction piping up to the downstroas weld on the last elbow prior to primary containment penetration

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N-14 I

I Section B includes piping from the downstrees weld on the last elbow prior to primary containment penetration N-14 and connected piping to a point just downstream i

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of containment isolation valve HO-18.

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Section C includes the balance of the 4" RWCU piping downstress of the outboard isolation valve and the l

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remaining RWCU piping.

1 2.3.3 Welds Excluded from the Scope of Generic Letter 88-01.

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Certain portions of the Residual Heat Removal (RRR) and the Core Spray systems, according to the Philadelphia Electric l

Submittal, operate at temperatures below 200'F and are.

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therefore, outside of the scope of Generic Letter 88-01.

These sections of piping are as follows:

RRR piping beyond valves A0-46A and B and piping beyond i

valve HO-18.

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Core Sprsy piping beyond valves 14A and B.

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Table 3 l

l Summary of Piping Replacement at Peach Botten 2 l

l Material fase note a)

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l Srstes Pininn/Forminas Field Welds Cates.

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316SS Cont. Chem.

<.02 C, SFW A

f ReactorRecirculogn l

Suction Pi ing l

Discharge 1 ping (b) 316SS Cont. Chem.

<.02 C, SFW A

N2 Nozzle Safe-Ends 316SS Cont. Chem.

ER308/ER309, 8FM A

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N1 Nozzle Safe-Ends Non-conforming Non-conforming D4G I

Residual Heat Removal 316SS Cont. Chem.

(.02 C, SFN A

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Core Spray Piping 316L (<.02 C)

E308L(g)

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RPV N5 Nozzle / Safe-end Non-conforming Non-conforming D&G j

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A RWCU(d) - Section A 316L (<.02 C)

E308L I

- Section B 316SS Cont. Chem.

<.02 C, 8FN A

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- Section C Non-conforming Non-conforming G

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RPYS - Jet Pump Inst.

l Penetration Seals, 316SS Cont. Chem.

1 Safe-Ends, and Velds Low C SS (<.023 C) <.02 C, 8FN A

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t (a) 316SS Cont. Chem. (controlled chemistry) contains <0.02 carbon and l

nitrogen additions for added strength.

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(b) Meets General Electric document E50YP11 for intergranular attack,'

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and shop welds were solution treated after welding.

l (c) Complete composition has not been confirmed for some of the RWCU welds, but for those that have been confirmed, the material is E308L.

Similarly, information necessary to determine IGSCC resistance is i

partially indeterminable for some Core Spray and RWCU welds. For i

these cases, the IGSCC classifications are based on comparisons with similar welds of known composition and ICSCC resistance.

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(d) RWCU - See text for explanation of which sections of piping are contained in Sections A, B, and C.

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i' 2.3.4 Previous Inspection Proarama The Philadelphia Electric Submittal did not prwide information concerning inspection schedules ascept the noe IGSCC Category D weld in the Recirculstica system and the two IGSOC Category D welds in the Core Spray system. These inspections were reported to have boom conducted using astbeds and personnel in conformance with NRC Staff recommendations,-

and no flaws were found.

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2.3.5 Evaluation of Previous Mittaatina Actions l

and Inspections An extensive piping replacement program has been conducted at Peach Botton 2 with the result that 375 of the 478 welds that are vithin the scope of Generic Letter 88-01 are IGSOC Category A welds. However six nozzles to safe-ends (N8, N9, N10, Nil, N12, and N16), four welds in the Recirculation j

j system, four welds in the Core Spray, and 95 of the 96 welds in the RWU that are outboard of the isolation valves contain l

l non-resistant material, Only three of these have been j

j inspected. These inspections were conducted using methods l

and personnel that comply with the NRC Staff position. Thus, l

the three welds that were inspected are classified as IGSOC Category D, and the remainder of the non-resistant welds i

are classified as IGSCC Category G.

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l Philadelphia Electric experienced difficulty finding some l

of the data (composition and/or IGSCC resistance) required for classification of some of the welds in replacement piping, but the approach they took in comparing those welds with other simila'r welds with kr.own composition and IGSOC resistance is a technically valid approach, and it is i

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recommended that the Philadelphia Electric's cleasifications 4

should be accepted.

2.4 g rrent Plans for Mitimatina actions i

2.4.1 Summerr of Plans i

Philadelphia Electric stated that stress improvement of unmitigated welds is not planned. Rather, the thrvet of their IGSCC sitigation program at Peach Settos 2 is to replace or remove susceptible piping with resistant material. The 6" NPS Reactor Vessel head spray piping, from valve NO32 to the Reactor Yessel head spray flange is scheduled for removal during the next refueling outage. In addition, water cheatstry control, an augmented inspection progras, and leakage detection are planned as discussed below.

2.4.2 Vater Chemistry Control Philadelphia Electric Submittal No. I contains t.he following statement concerning veter chemistry control

" Water chemistry control at Peach Bottos 2 is detailed in Rev. O of Philadelphia Electric Company's 'BWR Water Chemistry Control Progras,' dated December 11, 1987.

The water chemistry control requirements in this program are in accordance with the Bk?. Ovners Group and Electric Power Research Institute (EPRI) Water Chemistry Guideliner, existing General Electric chemistry recommendations, and INPO recomr.,endations."

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2.4.3 Evalustion of Conformance to Staff Positions j

and Reconsendation j

Extensive sitigating actions have already been applied, so ~

j that 375 of the 484 welds within the scope of Generic Letter l

88-01 at Peach Botton 2 are IGSOC Category A welds. Although l

more than more than 100 IGSOC Category D and G welds still l

exiat at Peach Botton 2, additional piping removal is planned, f

and (as discussed below) en augmented inspection program j

is planned. Thus, acceptance of Philadelphia Electric's l

position is recommended, j

2.5 Plans for Future Inspections 2.5.1 Summary of Inspection Schedules l

Philadelphia Electric Submittal No. I states that the f

inspection schedules for Peach Bottom 2 are being revised l

to reflect the requirements for inspection schedules as t

delineated in NUREG 0313. Revision 2 and Generic latter 88-01.

j Philadelphia Electric Submittal No. I contains a listing

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of welds to be included in planning the inspection schedules; j

however, actual inspection schedules were not provided.

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In addition, the six IGSCC Category G nozzle to safe-end f

welds (N8, N9, N10, Nil, N12, and N16) are not included in i

l the list of welds that are considered to be in the scope l

l of Generic Letter 88-01 however, these welds were noted l

l in Philadelphia Electric Submittal No. 1.

l 2.5.2 Personnel and Methods i

Philadelphia Electric Submittal No. I states that inspection methods and personnel qualifications will comply with the f

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NRC Staff position as delineated in Generic 1.etter 88-01.

It further states (1) For ultrasonic testing inspectable ASME Class 1 and 2 welds, the IGSCC inspections will menerally l

be performed in accordance with the requirements contained in the applicable edition and addenda of ASME Section II for the ASME class of weldsent. (2) For ultrasonically inspectable ASME Class 3 and non-class welds, the requirements in Section I? for Class 2 welds will apply. (3) The edition

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and addenda of ASME Section II used for determining these j

j requirements will be as dictated by paragraph (g) of 10CFR50.55a.

(4) The personnel performing the IGSCC l

volumetric inspections will be qualified for such inspections by a formal program approved by the NRC.

3 2.5.3 Sample Expansion i

Philadelphia Electric's position on Sample Expansion is in compliance with the NRC Staff position. Specifically, if 7

l one or more Category A, B, or C welds are found to be cracked, l

or if additional cracks or significant crack growth is discovered in a Category E weld during the interval, a sample expansion plan will be invoked which will be in accordance with the NRC Staff position on Sample Expansion as delineated in Generic 1,etter 88-01.

1 2.5.4 Plans for Uninspectable Welds The RWCU welds outside of containment are presantly considered to be uninspectable by UT. Philadelphia Electric plans to l

verify the integrity of these welds by pressure tests in l-accordance with the requirements of Section II Article IWB, l

IWC, or IWD-5000, and they plan to revise the Peach Bottom l

2 pressure test procedures to incorparate this portion of the RWCU system. The reason these welds are considered to 13 s

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f be uninspectable was not provided.

2.5.5 Evatustion and Recommendations Philadelphia Electric stated that they will follow the NRC j

Staff position on inspection schedules (with the exception of the RWCU welds that are outside containment), so acceptance of their position on inspection schedules for welds other than the RWCU welds outside of containment is recommended.

l However, two action items are also recommended:

(1) The list of welds that are included in the Peach Botton 2 IGSCC program should be modified to include the six nozzle to safe-end welds included in their submittal but omitted from the actus1 list.

(2) Philadelphia Electric should submit (to the NRC Staff) actual inspection schedules which verify their statement that schedules will follow requirements of Generic Letter 88-01.

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The reasons that RWCU welds outside of containment are considered to be uninspectable were not provided so it is not possible to evaluate the claim of uninspectability.

It is presumed in this report, however, that these welds are not actually uninspectable because most such welds in numerous other BWR nuclear plants are inspectable. Thus, it is recommended that Philadelphia Electric should either demonstrate that those welds are uninspectable or amend their IGSCC UT Inspection program to include the RWCU welds that 1

are outside of containment.

Although Philadelphia Electric stated that they are committed to complying with the NRC Staff positions on inspection 14

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methods and personnel as delineated in Generic Letter 88-01, they also stated that vitrasonic testing of inspectable ASME Class 1 and 2 welds will menorelly be performed in l

accordance with the requirements contained in the appitcable l

edition and addends of ASME Section II for the ASME class l

l of weldsent. 'Ihe term " generally" implies that there will l

be exceptions and deviations from their stated position of f

compliance with the requirements of Generic Letter 88-01.

l Thus, rejection of their position on this ites is recommended.'

Philadelphia should amend their position concerning inspection methods and personnel to be in total, compliance with the NRC Staff position.

Philadelphia Electric's position on sample expansion is in compliance with the NRC Staff position, so acceptance of this position is recosaended.

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2.6 Channes in the Technical Specification Conceninn ISI 1

Philadelphia Electric Submittal No. I states that a change to the Technical Specifications will b6 proposed and submitted by December 31, 1988. The proposed change will add the following statement i

to Section 4.6.G of the Peach Bottom 2 Technical Specification:

"The Inservice Inspection (ISI) Program for piping identified in the NRC Generic Letter 88-01 shall be performed in accordance with the staff positions on schedule, methods and personnel, and sample expansion included in NRC Generic Letter 88-01.

j Details for the implementation of these requirements are included as augmented inspection requirements in the ISI program."

Philadelphia Electric also stated that a similar statement would 15 i

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be added to the Peach Bottos 2 FSAR, Appendia I, page I-1, which controls the ISI program.

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l However, their position is revised in Philadelphia Submittal No.

2 which presents an alternative position. That alternative position is reviewed in Section 3 of this report.

2.7 Confirmation of Leak Detection in the i

Technical Specification f

2.7.1 Philadelphis Electric's Position Philadelphia Electric Submittal No. 1 states that the existing Technical Specifications are in conformance with the NRC Staff position on leakage. It further states that the Peach Bottom Technical Specifications 3.6.C and 4.6.C contain the l

following:

"The Technical Specifications require that Reactor Coolant unidentified leakage shall be limited to 5 gpa or the j

unit shall be in hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in l

cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."

"The Technical Specifications require that the rate of change of Reactor Coolant unidentified leakage.shall not exceed 2 spa within a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period or the unit shall be in hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."

"The Technical Specifications a,M re that total Reactor Coolant System leakage be limited to 25 spa averaged over any 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> surveillance period or'the unit shall be in hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown 4

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h<

e within the fo? lowing 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."

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i "The Technical Specifications require that the primary containment (drywell) sump collection and flow monitoring system be operable during reactor power operation. From and after the time the system is made or found to be inoperable for any reason, reactor power operation is permissible only during the succeeding 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> unless the system is made operable sooner. Operability of this system is defined as the ability to measure reactor coolant leakage."

"The Technical Specifications require that the Drywell J

Atmosphere Radioactivity Monitor shall be operable during reactor power operation as a supplement to the reactor coolant leakage monitoring system. From and after the time the system is made or found to be inoperable for any reason, reactor power operation is permissible for up to 30 days provided grab samples of the containment atmosphere are~obtained and analyzed at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" "The Technical Specifications require that the drywell atmosphere radioactivity levels shall be monitored and recorded at least once per day."

"The Technical Specifications require that Reactor Coolant System leakage be monitored and recorded every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> usfng the primary containment (drywell) sump collection and flow monitoring system."

2.7.2 Evaluation and Recommendation The Peach Bottom 2 Technical Specifications pertaining to e

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i Leakage Requirements are currently in compliance with the NRC Staff position as delineated in Generic Letter 88-01.

It is roccaneaded, therefore, that the Philadelphia Electric position on leakage should be accepted.-

2.8 Plans for Notification of the NRC of Flows 2.8.1 Philadelphia Electric's Position Philadelphia Electric plans to adopt the NRC Staff position on notification. If.any flaws are identified which do not i

meet the referenced criteria for continued operation, the NRC will be duly notified of the disposition of the affected l

flaws, and NRC approval of the disposition for each flew exceeding the criteria will be obtained before operation is resumed.

i Pertaining to evaluation of flaws: Flaws exceeding the j

acceptance criteria of IWB-3500 of ASME Section II will be evaluated, then either repaired, replaced or deemed acceptable for continued operation. Repairs or replacements will be documented in the Owners Report for Repairs and Replacements as required by ASME Section II. Evaluations of flaws for continued operation will be performed in accordance with the requirements of NUREG 0313. Revision 2 in conjunction i

f with the criteria in IWS-3600.

i 2.8.2 Evaluation and Recommendation l

Since Philadelphia Electric plans to comply with the NRC Staff position, it is recommended that the plans for reporting of flaws and evaluation of flaws should be accepted.

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3. ALTERNATIVE POSITION 3.1 Alternative Position Concernina ISI i

in the Technical Specification 3.1.1 Philadelphia Electric's Position As indicated in Section 2.6 of this report, Philodelphia Electric initially agreed to amend the Peach Botton 2 I

Technical Specification on ISI to include a statement that the inservice inspection program would comply with the NRC Staff position on inspection schedules, methods and personnel, and sample expansion. However, that position was revised as stated in Philadelphie Electric Submittal No. 2 which l

states:

"Upon review of other licensees' responses to Item 3, p

and subsequent discussions with the Lead NRC Project Manager for this Generic Letter, we have concluded that inserting the recommended statement into the Technical Specifications is not necessary or appropriate.

the staff positions on Intergranular Stress Corrosion l

Cracking (IGSCC) will be incorporated into our ISI Program document. This position is consistent with the philosophy '

of the Technical Specifications Improvseent Program which encourages the relocation of various specifications to other licensee controlled documents. Therefore, this letter amends our original response to Item 3 of Generic Letter 88-01 by withdrawing our commitment to propose an amendment to the Technical Specifications concerning I

our ISI Program."

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3.1.2 Evaluetton and Recommendation Philadelphia Electric's stated position is that the ISI program document for Peach Botton 2 will incorporate a l

statement that the ISI program will comply with the NRC Staff position. This does not adequately fulfill or substitute for the requirement that such a statement should be incorporated into the Technical Specification. In fact, Generic Letter 88-01 specifically rejects the approach of placing the statement in the ISI program document. Thus -

rejection of Philadelphia Electric's position is recommended.

It is further recommended that Philadelphia Electric should amend the Technical Specification on ISI as required by Generic Letter 88-01.

4. CONCLUSIONS AND RECOMENDATIOFS Philadelphia Electric endorsed nine of the thirteen NRC Staff positions as delineated in Generic Letter 88-01 (i.e.', those pertaining to materials, processes, partial replacener:t, crack evaluation and repair criteria, inspection methods and personnel, inspection schedule, senple I

expansion, leakage detection, and reporting requiren.ents). Concerning processes, Philadelphia has applied solution treating but they have not applied stress improvement or heat sink welding. They did not provide an indication of acceptance or rejection of the NRC Staff positions concerning weld overlay, stress improvement of cracked weldments, and clamping devices. Concerning water chemistry, they indicated that they use controlled water chemistry, but as best as it could be determined from their submittals, the water chemistry f

control at Peach Botton 2 does not involve hydrogen water chemistry.

Most of the welds (375 out of a total of 484) at Peach Botton 2 are IGSCC Category A welds. This large number is the result of extensive 20

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E The remaining piping replacement programs conducted at Peach Botton 2.

103 welds contain non-reaistant material and only three of these have been inspected (no flaws were found). Thus Peach Botton 2 has 100 IGSCC Category G welds and 3 IGSOC Category D welds.

6 The thrust of the Philadelphia Electric program at Peach Bottom 2 is piping replacement / removal rather than stress improvement, additional piping removal is scheduled. As mentioned above, they also plan to i

continue water chemistry control (but not HWC).

Philadelphia Electric agreed to comply with the NRC Staff positions concerning inspection schedules, inspection methods and personnel, sample expansion, and reporting requiremente. They did not submit actual inspection schedules which confirm their statement of compliance with the NRC Staff position, but they did submit a list of welds that fall within the scope of Generic Letter 88-01. However, they excluded six nozzle to safe-end welds from that list, and in elaborating on their conformance with the NRC Staff position on inspection methods, 4

they added two provisions (or exceptions). First, they stated that RWCU welds outside of containment are considered as inaccessible for l

UT inspection and would add hydrostatic tests of this piping. Second, they stated that UT inspections will generally be conducted in

~

accordance with requirements of ASME Section II, and the word

" generally" implies exceptions (although no specific exceptions were i

l detailed in their submittal). These provisions are unacceptable.

I Philadelphia Electric initially agreed to change the Technical Specification concerning ISI, and they stated that a proposed amendment vould be submitted by December, 1988. Later, they changed their position and stated that the required statement would be added to the ISI program document rather than the Technical Specification. This approach is specifically rejected in Generic Letter 88-01.

I The Technical Specification concerning leakage is already in compliance 1

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with the NRC Staff position as delinsated in Generic Letter 88-01.

As a result of this technical evaluation, the following recommendations are made.

(1) Acceptance of Philadelphia Electric's position on sitigation of ICSCC and their assignment of IGSOC Classifications of welds in Peach Botton 2.

(2) Tentative acceptance of Philadelphia Electric's plans pertaining to inspection schedules (except for the RWCU welds outside of containment) pending confirmation (with actual inspection schedules) of their announced intention of compliance with the NRC Staff position.

(3) Unless Philadelphia Electric can demonstrate that the RWCU welds outside containment are really inaccessible (rather than just cos.:idered so), these welds should be included in IGSCC 1

UTinspec$1onplanandinspectedinaccordancewiththeschedule outlined in Generic Letter 88-01 for IGSCC Category G welds.

(4) Rejection of Philadelphia Electric's position on inspection methoJs and personnel until they eliminate or acceptably clarify the word " generally" which was used in their description of their plans.

1 G) Acceptance of Philadelphia Electric's position on sample expansion.

l (6) Rejection of Philadelphia Electric's position on changing the Technical Specification concerning ISI. Philadelphia Electric l

should amend the Peach Bottom 2 Technical Specification as I

l initially promised in their original submittal (Philadelphia Electric Submittal No. 1).

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(7) Acceptance of Philadelphia Electric's position concerning the f

Technical Specification on leakage detection.

(8) Acceptance of the remaining portions of the Philadelphia Electric Submittels.

5. REFERENCES 1.

" Technical report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping," NUREG 0313. Revision

2. U.S. Nuclear Regulatory Consission, Of fice of Nuclear Reactor Regulation, January, 1988.

2.

" Investigation and Evaluation of Stress 4 orrosion Cracking in Piping of Light Water Reactor Plants," NUREG 0531, U. S. Nuclear Regulatory Cosaission, February, 1979.

3.

"NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping,"

Generic Letter 88-01, U.S. Nuclear Regulatory Commission, January 25, 1988.

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