lJ Structural Integrity Associates, Inc. Report No.: 0900235.401.RO Project No.: 0900235.00 March 19,2009

G-Scan™ Assessment of 8" Condensate Water Storage Tank Return Line CD-183

Prepared by:

Reviewed by:

Approved by:

Inspection Date: February 17th, 2009

Prepared for:

Entergy

Indian Point Generating Station

Unit 2

Prepared by:

Structural Integrity Associates, Inc. Cerritos, California

Alex Bass

~ Larry Weigel

~/~ Ken Rach

Date: 03113/09

Date: 03/l3/09

Date: 03/19/09

Sfm'ctIJllllntegrity Associates, Inc.

ENT000579 Submitted: October 2, 2012

REVISION CONTROL SHEET

Document Number: 0900235.401.RO

Title: G-Scan™ Assessment of8" Condensate Storage Tank Return Line CD-I83

Client: Entergy, Indian Point Generating Station, Unit 2

SI Project Number: 0900235.00

Section Pages Revision Date Comments

All All o 03/19/09 Initial Issue

S'fllrCtlll31lnt,grity Associates, Inc.

Table of Contents

Section Page

1.0 INTRODUCTION .............................................................................................................. 1

2.0 INSPECTION AND TESTING TECHNIQUE ............................................................... 1

2.1 G-Scan™ Technique ........................................................................................................ 1

2.2 B-Scan Technique ............................................................................................................ 4

3.0 INSPECTION RESULTS ................................................................................................. 6

4.0 SUMMARY AND CONCLUSIONS ................................................................................ 7

APPENDIX A G_SCAN™ SHOTS .............................................................................................. 8

APPENDIX B CAD ISOMETRIC DRA WINGS ...................................................................... 11

APPENDIX C EQUIPMENT AND TECHNICIAN CERTIFICATES .................................. 13

0900235.40 l.RO srmrcw'Bllnt.,rlty AssOCiates, Inc.

List of Tables

Table I: Description of G-Scan™ Indication Coding ................................................................... .4

Table 2: Summary of the G-Scan™ Results ................................................................................... 6

Table 3: Summary of the B-Scan Results ....................................................................................... 7

List of Figures

Figure 1: Typical G-Scan ™ data and corresponding pipe features ................................................ 2

Figure 2: Detectable combinations of flaw depth and width for G-Scan™ inspection of 8.625-

inch x 0.322-inch wall pipe ...................................................................................................... 3

Figure 3: B-Scan Image of Corrosion .............................................................................................. 5

ii e Structumllnte,rity Associates, Inc. 0900235.401.RO

1.0 INTRODUCTION

Structural Integrity Associates, Inc. (SI) performed a long range guided wave (G-Scan TM)

inspection at Entergy Indian Point Generating Station, Unit 2 (Entergy) on February 17m, 2009.

Allen Schuele was the lead inspector on site during the Entergy inspection. The G-Scan TM

inspection was performed on 8" Condensate Storage Tank Return Line CD-I83 to screen several

pre-selected sections of pipe for wall loss. The inspection was performed while the plant was in

operation and water was flowing through the pipes.

In addition to the G-Scan™ piping interrogation, B-Scan ultrasonic inspection was used to

measure the nominal wall thickness of each pipe segment and to "prove-up" specific G-Scan ™

results by quantifying the depth of corrosion at specific locations of interest. B-Scan readings

were taken within the G-Scan™ collar "dead zone" (Le., typically a 2-3 foot length of pipe under

and immediately adjacent to the G-Scan™ collar-shown as a solid green vertical stripe in the G­

Scan traces) to insure the integrity ofthe pipe.

2.0 INSPECTION AND TESTING TECHNIQUE

2.1 G-Scan™ Technique

The torsional guided wave system used in this examination is the third generation GUL System

developed by the Imperial College ofthe UK and manufactured by Guided Ultrasonics LTD.

The torsional waves are computer generated at a continuous range of frequencies from 18 to 40

KHz.

The G-Scan™ system is a low frequency ultrasonic guided wave technique developed for the

rapid survey of pipes to detect both internai and external corrosion. Guided wave ultrasonic

inspection uses multiple transducer arrays to direct sound energy in a circumferential mode,

which creates torsional guided waves. These torsional waves propagate down the pipe and

reflect off features such as welds, supports, or areas of wall loss. Reflections are presented in a

0900235.401.RO 1 ~ ;.. "Integrity Associates, Inc.

pseudo A-scan format on the computer screen in either black (axi-symmetric reflection) or red

(non-axi-symmetric reflection) as illustrated in Figure 1 below. The black lines' amplitude is

proportional to the total cross sectional area change. The red lines' amplitude is inversely

proportional to the extent that the cross sectional area change covers the circumference of the

pipe. Interpretation of the inspection results is based on integration of these two signals'

amplitude, symmetry, and wave shape, and incorporates detailed pipe design, installation, and

operational information.

2.0 -F

1.5 > ~.o Q.

E <C O.5

0.0

Welds

Figure 1: Typical G-Scan™ data and corresponding pipe features

Under optimum conditions, the G-Scan™ system is sensitive to metal loss as low as 3% of the

pipe wall cross sectional area, but under actual field conditions reliable detection of metal loss

flaws should be generally assumed at between 6% and 9%.

Figure 2 illustrates the typical flaw size detection limits for G-Scan™ when used on 8" pipe, like

those inspected at Entergy. For this survey 5% sensitivity was empirically estimated.

2 Stnll:III"."ntsgrity Associates, Inc. 0900235.401.RO

0.320

0.300

0.280

0.260

0.240 _ 0.220 .t::. g 0.200

~ ~:~: Gl

Q 0.140

~ 0.120

i! 0.100

0.080

0.060

0.040

0.020

0.000

8.625-inch x O.322-inch Pipe GScan Flaw Detection Limits at Indicated % Sensitivity

o 1 2 3 4 5 6 7 8 9 1011 1213 14151617 18192021 22232425 2627

Flaw Circumferential

Figure 2: Detectable combinations of flaw depth and width for G-Scan™ inspection of 8.625-

inch x 0.322-inch wall pipe

Depending upon the sound attenuation characteristics of the pipe, coating, and contents, this

inspection technique can interrogate up to 200 feet in each direction for tests conducted on

above-ground pipe in good condition and 75 feet for underground pipe. However, guided waves

are significantly attenuated when passing through mechanical couplings and some types of

fittings. Generally, the guided wave signals cannot be accurately interpreted after passing

through flanges, some reducers, victaulic couplings, or multiple elbows. As a result, the

inspectable distance will often be less than 100 feet in each direction.

The G-Scan™ survey technique is very accurate at locating the axial position of piping

anomalies. G-Scan™ can identifY whether the anomaly is at the top, bottom, or sides of the

pipe, but cannot distinguish between internal and external anomalies. This technique is best used

as a pipe survey tool. Estimates of the wall thickness change can be derived from the data, but

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accurate measurement of flaw dimensions require that the anomaly be inspected using a

technique capable of more quantitative measurements of wall thickness. SI uses B-Scan

ultrasonic inspection to perform detailed examination of anomalies detected by G-Scan ™ on

accessible pipe segments. ID versus OD corrosion cannot be distinguished with the G-Scan™

system.

Wall loss is reported using two measures of defect dimensions - Estimated Cross sectional Loss

(ECL) and the extent of circumference affected. The black (axi-symmetric) signal reflections

indicate the estimated change in pipe cross sectional area, expressed as the percentage ECL. The

circumferential extent of a feature is indicated by the ratio of red (non-axi-symmetric) signal

amplitude to black (axi-symmetric) signal amplitude.

The terms and colors shown in Table 1 are used to interpret and report corrosion indications:

Table 1: Description of G-Scan™ Indication Coding

Estimated Wall Indication Type Color

Loss

Minor Black Oto20%

Medium Blue 21%to 49%

Severe Red 50% and greater

2.2 B-Scan Technique

The Phoenix Ultrasonic B-Scan imaging system utilized during this inspection can profile the

pipe wall in two dimensions, verify original wall thickness, and profile corrosion pitting. The

Ultrasonic B-Scan scanning system provides a cross sectional video view of pipe thickness by

scanning in real time. As the scan head passes over each section of pipe, the video screen

displays general wall thickness and remaining wall thickness at corroded areas and isolated

corrosion pits. When corrosion pits are located, the diameter and depth of these pits are profiled.

Examples of the display are included in Figure 3 below.

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Log File Name: Instrument Serial Number:D03 Transducer: 5 Mhz Part Number: 84" Straignt segement Location 1 Inspector: Allen Schuele Level III Company: ABC Pipeline

TYPE:T.SCAN ..... o..;",;I;,:;;,;: ..... ----..,1I'I'r1'l'

POS:ENCODED L-R __ 1-+--+"1'

MULT:IP·1ST POL:POS ~ _________ ......

CONTrOl Y:CONTACT

AGC:OFF

Ip·SUP:OFF

SINGIDUAl:DUAl

GAIN: 54.30 dB

IF BLOCK: O.l)4(;4(

ECHO-BLK: 0.023

MEAS TIME: 62.91

ZERO:3047

VElOCITY:0.2320

LOW:O.200

DElAY:O.OOO

RANGE:1.253

RECT:RF

INDEX:1

THRESH:40.0'% 1-______________ ---, HIGH:1.400

IP BLOCK: 0.0802 B-scan #7

Note 1: Pitting area lowest minimum was 0.247" Note 2: Pitting diameter 0.240· and 0.264" Note 3:

SCAlE:7

Figure 3: B-Scan Image of Corrosion

Area 1: Digital display of thickness at location indicated by cursor at location "A"

Area 2: RF display ofUT A-Scan signal associated with position indicated by cursor at "A"

Area 3: B-Scan display

Location A: Cursor used to select position

Location B: Top (outside) surface of pipe

Location C: Inside surface of pipe

Location D: Typical indications of corrosion pits. Depth is measured by moving the cursor over

the pit location (see note I for example). The width of the pit can also be measured (see note 2

for examples).

The display illustrates an axial scan length of about 5.8 inches at the selected scale.

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G·

3.0 INSPECTION RESULTS

The results of the G-Scan™ inspection are summarized in Table 2 below. The detailed results of

G-Scan™ shot including the G-Scan TM waveforms are included in Appendix A. Appendix B

includes CAD isometric drawing which illustrates the approximate piping configurations, locate

where G-Scan TM shots were taken, list the UT thickness (B-Scan) results at each inspection

location, and list the most relevant G-Scan TM results of the 2009 inspection.

At a majority of the G-Scan™ inspection locations, a B-Scan UT inspection was performed to

quantify the nominal wall thickness and to "prove-up" specific G-Scan™ results by quantifying

the depth of corrosion at specific locations of interest. The results are included in both Table 3

and in the CAD drawing in Appendix B.

The G-Scan™ inspection indicates that after more than 30 years in service, there is some level of

degradation in the Unit 2 Condensate Storage Tank Return Line interrogated. Table 2 shows that

the G-Scan™ inspection found sporadic regions of pipe wall loss where there seems to be greater

than "normal" general wall loss and localized pitting. The level of corrosion in the inspected

areas of piping is estimated to be 20% to 85% wall loss ± 1 0%. Possible through wall hole noted

at feature +F9 located 16'7" from the collar in the positive direction.

Table 2: Summary of the G-Scan™ Results

Circ. Approx.

Scan™ Feature location ECl Affected Wall Class length of

Notes Reference ft % loss Corrosion DWGNo.

Shot # % %

This section of pipe appears to be 4796 +F2 4'2" 8 40 20 Minor a major concern. A·200607

+F3 5'3" 4 20 20 Minor

+FS 10'2" 4 20 20 Minor

+FB 15'1 17 20 85 Severe 3 in pn<::<:.ihla thro"'gh wall

+F9 16'T' 10 10 100 Severe 2in hole +FiO 18'1 17 20 85 Severe 4in

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Table 3: Summary of the B-Scan Results

Nominal Tmin Tnom Maximum Approx. G-Scan™ Measured Difference Shot # Pipe Size Measured in in wall loss

in in (Note 1) (Note 2) %

4796 8 0.314 0.328 0.014 4

Notes for Table 3:

[1] "Nominal Wall" (Tnom Measured) data represents the typical wall thickness of the pipe away from evidence of pitting or localized corrosion. The nominal wall thickness may be different from the original wall thickness if the pipe has experienced general corrosion around the majority of the circumference.

[2] The maximum wall thickness reduction is calculated from the difference between the specified nominal wall and the minimum thickness measured by B-Scan. In some cases, as a result of general corrosion, the measured nominal wall thickness could be different from the nominal wall thickness when the pipe was installed. As a result, the total wall thickness change could be greater than the amount reported here. On the other hand, some of the difference may not be caused by corrosion, but could be the result of normal variations in wall thickness that occur during the pipe manufacturing process.

4.0 SUMMARY AND CONCLUSIONS

The G-Scan™ / B-Scan inspections indicate that after more than 30 years in service, that there

was some level of degradation in the Unit 2 Condensate Storage Tank Return Line interrogated.

The level of corrosion in the inspected areas of piping is estimated to be 20% to 85% wall loss

± 1 0%. Overall, the G-Scan ™ inspection found sporadic regions of pipe wall loss where there

seems to be greater than "normal" general wall loss and localized pitting.

The greatest threat to the service water piping seems to be pitting which could generate through

wall holes sporadically throughout the system. Known leak verified at feature +F9 located 16'7"

from the collar in the positive direction.

7 lJ Structurallntsgrity Associates, Inc. 0900235.401.RO

0900235AOl.RO

APPENDIX A

G-SCAN™ SHOTS

8 ~ :;:. VS - _'.I1r1Cll.'f" _lllntegri" Associates, Inc,

Int~~rltvAssociates, Inc.

Test 10' G3-14#4796 Pipe: 8" CD-183 SHe: Indian Palm Unit 2

Location: Sleeve +1'5" Size: 8 inch (8. 175mm)

Tested: 17 Feb 200914:40 Tested by: Allen Schuele[SIA)

Ring: R2B08(930) Coniig: 4.0FR. TIO,I}

Catibration: Automatic (149.89 mV) Version: 3.94, Wavemaker G3-14

CHent: Entergy Procedure: GU 1.1

DAGs: CaII=7%, Weld=23%

General Notes; Un~ 2 Drawing number A-200607. Condensate Storage Tank Retum Line CO-183.

#4796.wg3

0900235.401.RO

Ukrasonic B-Scan thickness measurements were taken at the conar location "T' nominal 0.328" minimum 0.314". 5% shot SGnsiivity.

9 l) Structurlllln"~nn", Associates, Inc.

#4796,wg3

0900235.401.RO

Intf:j~ritVAssociates,

Test ID' G3-14114796 Pipe 8" CD-183 Site: Indian Point Unit 2

Location: Sleeve +1'S' Size: 8 inch (8,17Smm)

0_00298

0,0645

0_138

0,136

Extent Class

0

50

0

Bend

0 Mil10r

'~ __ ~ ____ H_~~_~' ___ 50 Bend

o Branch

0,258 70 Support .---~-----~~~----~-~--.~ ".

40 Branch ~~-----:-c- Bend

--~------~---

0091 End

10

Rins: R2B08(930) CoofIg: 4,OFR. T(O,1)

Caubration: Automatic (149,89 mV) Version: 3,94, Wavemaker G3-14

NOles

approximately wall loss

wall loss

wall loss

t) Structuralilltsgrity Associates, Inc.

APPENDIXB

CAD ISOMETRIC DRAWINGS

11 tt ..... ........ ulllntB'nly Associates, Inc. 0900235.401.RO

0900235.401.RO

8" CONDENSATE STORAGE TANK RETURN LINE CD-183

12 lJ Structlll7lllntsgrlty Associatss, Inc.

0900235.401.RO

APPENDIXC

EQUIPMENT AND

TECHNICIAN CERTIFICATES

13 lJ Stl1lcturallntegrity Associates, Inc.

Certificate This is to certify that

Has achieved level 2 proficiency in the lise of the Wavemaker™ G3 Pipe Screening System

was achieved by successfuUy completing the Guided Ultrasonics Ltd. training course use of Wavemaker™ 03 Pipe Screening System, am! demonstrating

unlC1er'Stanal~ of the use of guided ultrasonics by both written practical examination.

Date: October 2008

Course Tutor: David Alleyne GUL Chairman: MaloolndlU&!icU ~'w",_

~t1~~bIl# For validity of this qualification refer to the operator qualification card

14 ~ Structurallnteur/ty Associates, Inc. 0900235.401.RO

CERTIFICATE OF CONFORMANCE

IIt .... ".-!' ...... Integrity Associates Gridley Place

CA90703

Item Quantity Model No.

G3 Wavernaker

In Tolerance In Tolerance

Date: Date Due: P.O.#:

Description

Long Range Guided Wave System

Deeember 17,2008 March 17, 2009 V-LW T07U05KK

Serial No.

0314

Integrity Associates. Inc. hereby certifies that the above Instrument(s) mcet/or manufacturer's applicable performance specifications and is/are in good

The equipment used to calibrate these instruments is traceable to the National Institute Standard and Technology within limitation of the N.I.S.T.'s calibration service.

~quipl11lent Used: N.I.S.T Trace No.

15 {:! StmDtllrBlln'~:Jn"rtu Associates, Inc. 0900235 040 l.RO

Int~lmvAssociates, Inc.

Test ID: G3-i4#4780 Pipe: 3" cat. g3-14 Site: office

Location: flange -Z 6" Size: 3 inch

Tested: Dec 17 Z008 18:40 Tested by: Allen Schuele[SlA)

Ring: R2F03(1375) COl'lfig: I.SFR, T(0,1)

Calibration: Automatic (1440.07 mV)

Version: 3.96, Wavemaker G3-14

Cllent: office Procedure: GU 1.1

DAGs: CalI=7%, Weld=Z3%

General Na1es: Fiberglass Tape Measure Serial No, 1581206820, 3" Test loop Serial No. SI-0501.

Notes

-F1 .2'6" 18.9

16 lJ Structurallntellrlty Associates, Inc. 0900235AOl.RO

., Woddwld!.cw~nc~!'!?~ 1781! Gegrget0wn la •• • Huntington !Iel!eh • CA 97647 * Ph9Qc 714-893-2438 * fa, 714·827·384Q

\lleb Site bttJrl/www.ndts~

CERTIFICATE OF CONFOR.l\1ANCE

Strueturallntegrity & Associates 16912 Gridley Place

Date: DateDlle:

April 01, ZOOS April G 1, ZO(}9 9920 P04010SG

Cerritos, CA 90703 P.O.#: USA NDTS#: Attn: Larry Weigel 562-944-8210

0900235.401.RO

Quantity

Instrument Condition:

Received: Returned:

In Tolerance. In Tolerance

Model No.

PHOENIX

Description

ULTRASONIC B·SCAN

IMAGING SYSTEM

Serla! No.

04061005M

NDT Systems hereby certifies that the ahove Instrument(s) meetJor exceed manufacturer's applicable performance specifications and Ware in good working order. The equipment(s) used to calibra!e these instruments is traceable to the National Institute of Standard and Technology within limitation of the NJ.S.T. 's calibration service. The policies and procedures at this facility comply with ML-STD-45562A. The above stated results are applicable only to the items listed on this Certificate. This Certificate may not be reproduced, except in full, with out the written approval of NDT Systems, Inc.

N.I.S.T. Trace 1'\0.

Temperature: 72 Deg F. Humidity; __ -'tl!"'"-':>!:L

17 lJ Structurallntegr/If Associates, Inc.