Text

Provides NRC W/Degradation Mechanism Evaluation & Results of Element & Segment Risk Rankings.Util Intends to Submit Revised ISI Program Following NRC Review of Evaluations & Risk Ranking,As Stated in Ltr
	ML20210K424
Person / Time
Site:	Vermont Yankee
Issue date:	08/15/1997
From:	Duffy J; VERMONT YANKEE NUCLEAR POWER CORP.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	BVY-97-105, NUDOCS 9708190255
	Download: ML20210K424 (126)
	v • d • e

_-- . - _ _ . - ~

VERMONT YANKEE NUCLEAR POWER CORPORATION Ferry Road, Drattleboro, VT 053017002 GREM 10 ENGINEERING OFFICE

680 MAIN STREET

DOLToN. MA 01740 (506) 77H711 August 15,1997 BVY 97-105

- United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

References:

(a) Ucense No. DPR 28 (Docket No. 50-271)

(b) Letter, VYNPC to USNRC, BVY 97-99, dated August 6,1997

Subject:

Implementation of ASME Code Case N560 at Vermont Yankee Nuclear Power Station in Reference (b) Vermont Yankee provided NRC with its consequence evaluation in support of NRC's review and approval of ASME Code Case N560 (hereafter, the code case). The code case was issued by the ASME Boiler and Pressure Vessel Committee in late 1996 as an alternative to examination requirements for Class 1, Category B-J piping welds. The purpose of this letter is to provide the NRC witn our degraJation mechanism evaluation (Attachment I) and the results of the element and segment risk rankings (Attachment II).

As stated in Reference (b), Vermont Yankee intends to submit a revised ISI program following NRC review of our evaluations and risk rankings. Vermont Yankee intends to have a revised ISI program in place by December 31,1997 to support our Spring 1998 refueling outage inspection activities.

NRC's prompt review of the materials provided in support of this schedule is appreciated.

Vermont Yankee makes no new commitments with this letter.

We trust that this submittal provides sufficient information. However, if additional information or clarification is required, please contact this office.

Sincerely, VERMONT YANKEE NUCLEAR POWER CORPORATION O 7 awus James J. Du y

(

9708190255 970815 Licensing Engineer PDR ADOCK 05000271 g PDR

., , g ' g' 9 Region 1 Administrator Resident inspector -VYNPS ,.

Project Manager - VYNPS

Attachment I Degradation Mechanism Evaluation of Vennont Yankee Class 1 Piping in Support of ASME Code Case N-560

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l Attachment 11 Segment and Element Risk Ranking Results of Vermont Yankee Class 1 Piping in Support of ASME Code Case N-560 l

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Segment and Element Risk Ranking After completion of the consequence and degradation mechanism evaluations the next step in the N560 selection process is the development of segment and element risk ranking. The first step in the risk ranking process is the definition of piping (risk) segments. Risk segments consist of continuous runs of piping that,if failed, have the same consequences, and are exposed to the same degradation mechanisms. The next step in the risk evaluation is the determination of the segment risk categories. This is accomplished by combining the consequence and damage mechanism categories to produce a risk category for each segment. The assigmnent of a particular segment to a risk category is based upon the risk matrix concept as depicted in Table 17 of the code case. A detailed summary of the application of the above criteria is presented in the following tables (Tables 2 through 10). Table 1 provides an overview of the system level results. A

( system by system review of the results is presented as follows:

Core Spray (CS) - The core spray system consists of eight segments ranging in size from I element per segment (segments CS-001 & 007) up to 10 elements per segment (CS-004,

-008). Two segmerits (Os-Ou4,-00R) were assigned to Risk Category 2 (High Risk Region) due to their high consequenc #, ank (large LOCA initiating event) and being potentially susceptible to the TASCS uegradation mechanistn. Four segments were assigned to Risk Category 4 (Medium Risk Region) dae to their high consequence rank (large LOCA or interfacing system LOCA) and the lack of susceptibility to a degradation mechanism. The remaining two segments were assigned to Risk Category 7 (Low Risk '

Region) due to their low consequence rank and lack of an active degradation mechanism.

Tables 2 and 11 provide additional information with respect to the core spray system.

Feedwater (FW) - The feedwater syste- consists of twenty three segments ranging in size from 1 element per segment (FW-OL , -004, -010, -014. -017, -019, -021) up to 7 elements per segments (FW-020, -022). Six segments consisting of nine elements in total were assigned to Risk Category 1 (High Risk Region) due to their high consequence rank (large LOCA initiating event) and the locations being potentially susceptible to the FAC degradation mechanism. Six segments were assigned to Risk Category 2 (High Risk Region) due to their high consequence rank and susceptibility to thermal fatigue (i.e. TT or TASCS). One of the six segments (FW-016) has the potential for a LOCA outside containment. Nine segments were assigned to Risk Category 4 (Medium Risk Region) due to their high consequence rank (large LOCA or LOCA outside containment) and the lack of susceptibility to a degradation mechanism. Segment FW-017 was assigned to risk Category 5 (Medium Risk Region) due to its medium consequence rank (loss of FW and MS intiating event) and its susceptibility to TASCS. Segment FW-014 was assigned to N360.4. doe 1

Risk Crtegory 6 (Low Risk Region) due to its medium consequence rank (loss of IAV and MS intiating evem) and lack of an active degradation mechanism. Tables 3 and 11 provide additional infonnation with respect to the feedwater system.

Illgh Pressure Coolant Injection (IIPCI)- The IIPCI system consists of two segments, one of 12 elements (IIPCI-001) and one of 7 elements (IIPC' 002). Segment ilPCI-001 was assigned to Risk Category 4 (Medium Risk Region) due to its high consequence rank (large LOCA initiating event) and lack of an active degradation mechanism. Segment IIPCI 002 was assigned to Risk Category 6 (Low Risk Region) due to its medium consequence rank (isolable LOCA) and the lack of susceptibility to a degradation mechanism. Tables 4 and 11 provide additional information with respect to the HPCI system.

Main Steam (MS) - The main steam system consists of eight segments ranging in size from 3 elements per segment up to 30 elements per segment. Four segments (MS-001, -

003, -005, -007) were assigned to Risk Category 4 (Medium Risk Region) due to their i high consequence rank (large LOCA initiating event) and the lack of an active degradation j mechanism. Four segments were assigned to Risk Category 6 (Medium Risk Region) due j

to their medium consequence rank (potential for LOCA outside containment) and the lack of susceptibility to a degradation mechanism. Tables 5 and 11 provide additional information with respect to the main steam system.

Main Steam Drain (MSD)- The main steam drain system consists of fourteen segments ranging in size from 1 element per segment (segment MSD-008) up to 14 elements per segment (MSD-005, -006). Two segments (MSD408,-010) were assigned to Risk Category 5 (Medium Risk Region) due to their medium consequence rank (medium LOCA initiating event or potential LOCA outside containment) and being potentially susceptible to the TASCS degradation mechanism. The remaining segments were assigned to Risk Category 6 (Low Risk Region) due to their low consequence rank (small LOCA) and the susceptibility to TASCS (a small leak mechanism). Tables 6 and 11 provide additional infonnation with respect to the main steam drain system.

Reactor Core Isolation Cooling (RCIC) - The RCIC system consists of one segment (18 elements). This segment was assigned to Risk Category 6 (IAw Risk Region) due to its n.edium consequence rank (medium LOCA, containment perfonnance) and its lack of susceptibility to a degradation mechanism. Tables 7 and 11 provide additional infonnation with respect to the RCIC system.

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l Reactor Water Recirculation (RWRS)- The RWRS system consists of ten segments ranging in size from 1 element per segment (RECIRC-006, 008) up to 13 elements per segment (RECIRC-007). Two segments consisting of a total of two elements (RECIRC-006, -008)) were assigned to Risk Category 2 (High Risk Region) due to their high consequence rank (large LOCA initiating event) and being potentially susceptible to the thermal transient (1T) degradation mechanism. Six segments were assigned to Risk Category 4 (Medium Risk Region) due to their high consequence rank (large LOCA

- initiating event) and the lack of susceptibility to a degradation mechanism. The remaining two segments.were assigned to Risk Category 6 (Low Risk Region) due to their medium consequence rank (medium LOCA) and lack of an active degradation mechanism. - Tables 8 and 11 provide additional information with respect to the RWRS system.

Residual Heat Removal (RHR) - The RHR system consists of eleven segments ranging in size from i element per segment (RHR 010) up to 7 elements per segment (RHR-001, -

002, 005). Four segments (RHR-001, -003, -009, -011) were assigned to Risk Category 2 (High Risk Region) due to their high consequence rank (large LOCA initiating event or interfacing system LOCA) and being potentially susceptible to the thermal fatigue degradation mecht.nism (1T A/or TASCS). Four segments were assigned to Risk CateEory 4 (Medium Risk Region) due to their high consequence rank (large LOCA or interfacing system LOCA) and the lack of susceptibility to a degradation mechanism. One segment was assigned to Risk Category 6 (Low Risk Region) due to its medium consequence rank (isolable LOCA) and the lack of an active degradation mechanism. The remaining two segments were assigned to Risk Category 7 (Low Risk Region) due to their low consequence rank and lack of an active degradation mechanism.' Tables 9 and 11 provide additional information with respect to the RHR system.'

- Reactor Water Cleanup (RWCU) - The RWCU system consists of four segments. One segment consisting of two elements (RWCU-004) was assigned to Risk Category 4 (Medium Risk Region) due to its high consequence rank (potential for LOCA outside containment) and the lack of susceptibility to a degradation mechanism. Two segme:.ts -

. (RWCU-001, 002) were assigned to Risk Category 6 (Low Risk Reg!on) due to their medium consequence rank (medium LOCA) and lack of an active degradation mechanism.

Segment RWCU-003 was assigned to Risk Category 7 due to its low consequence rank and the lack of an active degradation mechanism. Tables 10 and 11 provide additional information with respect to the RWCU system.

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FMECA - Segment Risk Ranking Report; nw - =

Number Degradation - Me h C;ra qu ae Cua ;a ae Risk Risk Segment ID of Welds Lines in Segment Weids in Segneemt Mechanison Category ID(s) Category Category Rank CS-001 2 8-CS-4A CS4A-F3, CS4A-F3A N NONE 21 HIGH CAT 4 MEDIMt -

CS-002 3 8-CS-4A ' CS4A-Fl.CS4A-FIA CS4A-F2 N NONE 22 LOW CATI' LOW CS-003 1 8-CS-4A CS4A-F3DW N NONE 23 HIGH CAT 4 MEDIUM CS-004 10 8-CS-4A CS4A-F3ADW, CS4A-F3B, CS4A- TASCS SMALLLEAK 23 HIGH CAT 2 HIGH F4, CS4A-MFS.CS4A-MFSA, CS4A-MF5B,CS4A-MFSC, CS4A-MF5D,CS4A-MF6, CS4A-MF6A CS-005 2 8-CS-4B CS4B-F3.CS4B-F3A N NONE 24 HIGH CAT 4 MEDIUM CS-006 3 8-CS-4B CS4B-F1. CS4B-Fi A, CS4B-F2 N NONE 25 LOW CAT 7 LOW CS-007 I 8-CS-4B CS4B-F3DW N NONE 26 HIGH CAT 4 MEDIUM CS-008 10 8mB CS4B-F3ADU.CS4B-F3B, CS4B- TASCS SMALLLEAK 26 HIGH CAT 2 HIGH F4,CS4B-MFS CS4B-MFSA..

CS48-MFSB.CS4B-MFSC, CS4B-MFSD, CS4B-MF6, CS4B-MF6A I

Tr.ble 3 R@97 2223:55 PM FMECA - Segment Risk Ranking Report Degradation ^l Number .

Degradation Mechanisrn Consequence Consequence Risk . Risk Segment ID of Welds Lines in Segment Welds in Segment Mechanisms Category ID(s) Category Category ' Rank RV-001 1 10-FDW-18 FW18-F4 FAC LARGELEAK 36' HIGH CATI- HIGH FW-002 2 10-FDW-18 FWIS-FS-SA, FW18-F5 N NONE 36 HIGH CAT 4 - MEDIL%1 FW-003 5 10-FDW-18 FWIS-FSA-SB, FW18-FSA-SA, -Tr SMALL LEAK 36 . HIGH - CAT 2- HIGH FW14FSA,FW18-F6 FW18-N4C-SW FW-004 1 10-FDW-19 - FW19-F4 FAC LARGELEAK 31 IUGH CATI HIGH 1

HIGH MEDIL%f -1 FW-005 5 10-FDW-19 FW19-F4A. FW19-FS. FW19-FSA. N NONE 31 CAT 4 FW19-F6-SA, FW19-F6 RV-006 5 10-FDW-19 FW19-F6A-SB, FW19-F6A-SA, TT SMALLLEAK 31 HIGH CAT 2 ' HIGH.

FW19-F6A, FW19-F7, FW19-N4A- --

39 FW-007 3 10-FDW-20 FW20-F3B, FW20-Fl. FW20-FIB FAC LARGE LEAK 36 - HIGH CATI li.GH FW-008 5 10-FDW-20 FW20-FI A, FWu-F2, FW20-F2A, N NONE 36 HIGH CAT 4 MEDIUM FW20-F3-SA FW20-F3 FW-009 5 10-FDW-20 FW20-F3A-SB, FW20-F3A-SA. TT SMALL LEAK 36 HIGH CAT 2 HIGH FW20S3A FN20-F4,FW20-N4D-SW FW-010 1 10-FDP 21 FW21-Fi FAC LARGE LEAK 31 HIGH CATI HIGH FW-Oli 2 10-FDW-21 PN21-F2-SA, FW21-F2 N NONE 38 HIGH CAT 4 MEDIUM RV-012 5 10-FDW-21 RV21-F2A-SB, FW21-F2A-SA. TT SMALL LEAK 3! HIGH CAT 2 HIGH FW21-F2A, FW21-F3, FW21-N4B-SW FW-013 2 16-FDW-16 FWI6-MF7. FW16-F8 N NONE 27 HIGH CAT 4 MEDIUM s

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8m97 2:36:oo PM

.FMECA - Segment Risk Ranking Report t ' Degradation Number .

Degradation Mechanism Consequence Consequence Risk Risk '

Segment ID of Welds Lines in Segment -Welds In Seg nent Mechanisms Category IDis) Category Cdegory Rank

-l RV-014 1 16-FDW-16 FWI6-F8A N NONE 28 MEDIUM . CAT 6- LOW FW'-015 3 16-FDW-16 FW16-F9,FW16-19A FW16-F10 N NONE 29 ' - HIGH CAT 4 MEDIUM . .l RV-016 2 16-FDW-17 FW17-MP4, FW17-MF4A TASCS SMALL LEAK 32 HIGH CAT 2 ' HIGH RV-017 1 16-FDW-17 FWl7-FSA ' TASCS . SMALLLEAK 33 MEDIUM CAT 5' MEDIUM RV-018 2 16-FDW-17 FW17-F6, FW17-F6A - TASCS. SMALLLEAK '34 HIGH . CAT 2 HIGH -

RV-019 1 16-FDW-17 ~ FW17-F7 s .N NONE 34 HIGH CAT 4 - MEDIUM RV-020 7 ' 16-FDW-18 FW18-F2, FW18-F2A.FW18-F2B, N. NONE 35 HIGH CAT 4 MEDIUM ,

FWI8-F2C, FW . -F2D, FW18-F2E, FWI8-F3 RV-021 1 16-FDW-18 ' ' FW88-F3A FAC LARGE LEAK 35 HIGH -CATI HIGH . . ,

FW-022 7 16-FDW-19 RVl9-F2, FW19-F2A, FW19-F2B, N NONE 30 HIGH CAT 4 MEDIUM .

FW19-F2C, FW19-F2D, FW19-F3.

FW19-F3A FW fl23 2 16-FDW-19 FW19-F3B, FW19-F3C FAC LARGE LEAK 30 HIGH CATI HIGH 3

-I

~ TEble 4' m7 2:36:03 FM FMECA-- Segment Risk Ranking Report Degradation Number Degradation Mechanisna Co,agace Consequence Risk - Risk Segment ID of Welds Lines in Segment ~ Welds in Segment Mechanisms Category ID(s) Category : Category Rank:-

HPCI-001 12 10-MS-4A MS4A-Fl. MS4A-FI A, MS4A- N' NONE -52 HIGH . CAT 4 MEDIUM .

FIB, MS4A-FIC, MS4A-F2, MS4A-F2A, MS4A-F3, MS4A-F3A, MS4A-F3B, MS4A-F3C, MS4A-F3D, MS4A-F4 HPCI-002 7 10-MS-4A MS4A-FS, MS4A-FSA, MS4A-F6, N NONE 53,54 MEDIUM CAT 6 LOW - j

- MS4A-F6A, MS4A-F6B, MS4A- i F6C, MS4A-F7 4

_ _ _ _ . - _ _ _ - _ . - - _ _ _m- i '

Tchle 5 878s7 2:36:05 eM FMECA - Segment' Risk Ranking Report l Degradation '!

Number Degradation Mechanism Consequence Consequence . Risk Risk .l

- Segment ID of Welds Lines In Segment Welds in Segment Mechanisms Category : ID(s) Category Category " Rank '

MS-001 25 18-MS-7A MS7A-N3A-SW, MS7A-A8, N NONE 37 HIGH CAT 4- MEDIUM MS7A-A7D, MS7A-A7C,MS7A-A7B MS7A-A7A MS7A-A7, MS7A-A6B, MS7A-A6A, MS7A-A6, MS7A-ASK, MS7A-A5J, MS7A-ASI, MS7A-ASH, MS7A-A5G, MS7A-ASF, MS7A-ASE, MS7A-ASD, MS7A-ASC, MS7A-ASB, MS7A-ASA, MS7A-AS, MS7A-Al1. MS7A-A4A, MS7A-A4 MS-002 3 18-MS-7A MS7A-A3, MS7A-A9A, MS7A-A9 N NONE 38,39 MEDIUM CAT 6 LOW MS-003 26 18-MS-7B MS7B-N3B-SW, MS7B-B8, MS7B- N NONE 40 HIGH CAT 4 MEDIUM B7D,MS7B-B7C MS7B-B7B, MS7B-B7A, MS7B-B7, MS7B-B6D, MS7B-B6C, MS7B-B6B, MS7B-B6A, MS7B-B6, MS7B-B5H, MS7B-B5E, MS7B-BSF, MS7B-BSG, MS7B-B5B, MS7B.

B5C, MS7B-BSD, MS7B-BSA, MS7B-BS, MS7B-BI1.MS7B-B4C, MS7B-B4B, MS7B-B4A, MS7B-B4 MS-004 3 18-MS-7B MS7B-B3, MS7B-B9A, MS7B-B9 N- NONE 41,42 MEDIUM -CAT 6 LOW 5

.R

___________m_ _

l Table 5 I I

8/8/97 2:36:07 PM g,EG Segment Risk Ranking Report Degradation Number Degradation Mechanism Consequence Consequence Risk .- Risk Segment ID of Welds Lines in Segment Welds in Segment . Mechanisms Category ID(s) Category ' Category Rank MS-005 30 18-MS-7C MS7C-N3C-SW, MS7C-C8, MS7C- N NONE 43 HIGH CAT 4 MEDIUM '

C7D, MS7CC7C, MS7C-C7B, MS7C-C7A, MS7C-C7, MS7C-C6D, MS7CC6C, MS7C-C6B, MS7C-C6A MS7C-C6,MS7C-

CSK MS7C-C5H.MS7C-CSI, MS7CC5J MS7C-C5G,MS7C-CSF, MS7C-CSE, MS7CC5B, MS7C-CSC, MS7C-CSD, MS7C- ;

CSL, MS7C-CSA, MS7C-CS, MS7C-Cll, MS7C-C4C, MS7C-C4B, MS7C-C4A, MS7C-C4 MS-006 3 18-MS-7C MS7C-C3, MS7C-C9A, MS7C-C9 N NONE 44,45 MEDIUM CAT 6 LOW -

MS-007 24 18-MS-7D MS7D-N3D-SW, MS7D-D8. N NONE 46 HIGH CAT 4 MEDIUM MS7D-D7D, MS7D-D7C, MS7D-D7B, MS7D-D7A, MS7D-D7, MS7D-D6B, MS7D-D6A, MS7D-D6,MS7D-D5K MS7D-DSI, MS7D-D5J MS7D-DSH,MS7D-DSF, MS7D-D5G, MS7D-DSE, MS7D-DSD, MS7D-DSC, MS7D-DSB, MS7D-DSA, MS7D-DS, MS7D-D11 MS7D-D4 MS-008 3 18-MS-7D MS7D-D3, MS7D-D9A. MS7D-D9 N NONE 47,48 MEDIUM CAT 6 LOW 6.

L____________ - _-.1_ - -_ ._

Table 6 I

M7 2:36:09 PM

-FMECA - Segment Risk Ranking Report Degradation Number Degradation ' Mechanism Consequence Consequence Risk Risk 1 Segment ID of Welds Lines In Segment . Welds in Segment Mechanisms Category ID{s) Category Category Rank' MSD-001 3 1.5-MSD-420 MSD420-F9, MSD420-F8, TASCS SMAIL LEAK 55 LOW CAT 6 LOW-MSD420-F7 MSD-002 3- 1.5-MSD-421 MSD421-F7, MSD421-F8, TASCS SMALLLEAK 55 ' LOW CAT 6 LOW MSD421-F9 MSD-003 4 1.5-MSD-422 MSD422-F4, MSD422-F3. TASCS SMALL LEAK 55 LOW CAT 6 LOW MSD422-F2, MSD422-F1 MSD-004 8 2-MSD-2A MSD2A-F1, MSD2A-F2, MSD2A- TASCS SMA11 LEAK 55 LOW CAT 6 LOW F3. MSD2A-F4, MSD2A-FS,

' MSD2A-F6, MSD2A-F7, MSD2A- s MSD-005 14 2-MSD-2B MSD2D-F1, MSD2B-F2, MSD2B- TASCS SMALLLEAK 55 LOW CAT 6 LOW

- F3 MSD2B-F4, MSD2B-F5, >

~ MSD2D-F6, MSD2B-F7, MSD2B-F7A MSD2B-F7B,MSD2B-F7C, MSD2B-F7D, MSD2B-F7E, MSD2B-F7F, MSD2B-F8 MSD-006 14 2-MSD-2C MSD2C-F1, MSD2C-F2, MSD2C- TASCS SMALLLEAK 55 LOW CAT 6 - LOW F3, MSD2C-F4, MSD2C-FS, MSD2C-F6, MSD2C-F7, MSD2C- .

F7A,MSD2C-F7B MSD2C-F7C, MSD2C-F7D, MSD2C-F7E.

MSD2C-F7F,MSD2C-F8 MSD-007 8 2-MSD-2D . MSD2D-F1, MSD2D-F2, MSD2D-' TASCS SMALL LEAK 55 LOW CAT 6 LOW

. F3, MSD2D-F4, MSD2D-FS, MSD2D-F6, MSD2D-F7, MSD2D-F8 MSD-008 1 3-MSD-2 MSD2-FF TASCS SMALL LEAK 56 MEDIUM - CATS MEDIUM 7 ,

A. -

Table 6-

'~

- 8597 2:36:i3 FM FMECA - Segment Risk Ranking Report Degradation

Number - _

Degradation Mechanism . Consequence Consequence Risk ' Risk:.

Segment ID of Welds Lines in Segment Category . Category ' Rank Welds in Segment Mechanisms Category ~ ID(s) 1 MSD-009 2 3-MSD MSD2-F2, MSD2-F3 TASCS SMALLIEAK 57 LOW CAT 6 .. LOW MSD-010 5 3-MSD-2 - MSD2-F4.MSD2-SI,MSD2-S2, TAECS . SMALL LEAK 58,56 MEDIUM '

2 CATS MEDIUM MSD2-54, MSD2-S3 s

y $

8

Tcble 7 i 1

8/8/97 2:36:15 PM FMECA - Segment Risk Ranking Report )

neeradauen i Number Degradation Mechanism Consequence Consequence . Risk Risk Segment ID of Welds IJnesin Segment - Welds in Segment , Mechanisms Category ID(s) Category Category Rank-RCIC-001 18 3-MS-5A MSSA-Fl. MSSA-FI A, MSSA- N NONE 49,50,51 MEDIUM .. CAT 6 LOW j FIB. MSSA-FIC, MSSA-FID, -j MSSA-FiE. MSSA-F2, MSSA-F3.

MSSA-F3A, MSSA-F3B, MSSA-F4, MSSA-F4A, MSSA-FS, MSSA-FSA, MSSA-FSB, MSSA-FSC, MSSA-F6, MSSA-F7 9

i

1 i

Table 8

~

sis /97 2:36:i6 PM FMG ' Segment Risk Ranking Report l Degradation ~

~]

Number Degradation Mechanism Consequence Consequence - Risk l Risk Segment ID ;of Welds Lines in Segment Welds in Segment Mechanisms Category ID(s) Category Category Rank RECIRC-001 10 12-PLR-A RR-N2F-1, RR-N2F-2, RR-N2G-1 N NONE- 01 HIGH CAT 4F MEDIUM - d RR-N2G-2, RR-N2H-1, RR-N2H-2, i RR-N21-1, RR-N2J-2, RR N2K-1, RR-N2K-2 RECIRC-002 , 10 12-PLR-B RR-N2A-1, RR-N2A-2, RR-N2B-1, 'N NONE 02 HIGH ' CAT 4 MEDIUM RR-N2B-1 RR-N2C-1, RR-N2C-2, RR-N2D-1, RR-N2D-2, RR-N2E-1, RR-N2E-2 RECIRC-003 4 22-PLR-A RR-RH-A-1, RR-RH-A-2, RR-RH- N NONE 01' HIGH - CAT 4 MEDIUM A-3, RR-RH-A-4 RECIRC-004 4 22-PLR-B RR-RH-B-1, RR-RH-B-2, RR-RH- N NONE 02 HIGH CAT 4 MEDIUM B-3, RR-RH-B-4 RECIRC-005 12 28-PLR-A RR-AS-1, RR-AS-L RR-AS-3, RR- N NGNE 01 HIGli CAT 4 MEDIUM .

AS-4, RR-AS-5, RR-AS-6, RR-AS-

7. RR-AD-8, RR-AB-1, RR-AD-9, RR-AD-10, RR-AD-12 RECIRC-006 1 28-PLR-A RR-AD-13 'IT SMALL LEAK 01 HIGH CAT 2 HIGH RECIRC-007 13 28-PLR B RR-BS-1, RR-BS-L RR-BS-3, RR- N NONE- 02 HIGH CAT 4 - MEDIUM BS-4, RR-BS-5, RR-BS-6, RR-BS-

7. RR-BD-8, RR-BB-1, RR-BD-9, RR-BD-10, RR-BD-11, RR-BD-12 RECIRC-008 1 28-PLR-B RR-BD-13 TT SMALL LEAK 02 HIGH CAT 2 HIGH RECIRC-009 7 4-PLR-A RR-AB-2, RR-AB-3, RR-AB-4, RR- N NONE 03 MEDIUM - CAT 6 LOW AB-5, RR-AB-6, RR-AB-7, RR-AB-8 10 l _. - __ - =. _ _ _ _ - _ - _ _ _ _ _ - _ _ _ _ _ _ -

Table 8 l

4 8/8/97 2:36:19 PM -

FMECA. - Segment Risk' Ranking Report negr dation Number Degradation Mechanism . Consequence Consequence Risk . Risk -

Segment ID of Welds Lines in Segment Welds in Segment Mechanisms ' Category ID(s) Category Category Rank-RECIRC-010 7 4-PLR-B , R R-BB-2. RR-B B-3, RR-BB-4, RR- N .NONE 04 MEDIUM ' CAT 6 ' LOW -

BB-5, RR-DB-6, RR-BB-7, RR-BB-8 I

4

/

11

d s Ta' Die 9..- -

E7 2:3e2 FMECA - Segment Risk Ranking Report Degradaticu v Number Degradation Mechanism ' Consequence Consequence Risk - Risk Segment ID of Welds Lines in Segment Welds in Segment Mechanisms Category ID(s) Category . Category ' Rank

RHR-001 7 20-RHR-32 RH32-1, RID 2-1 RH32-3, RH32- TASCS SMALLLEAK 17 HIGH - . CAT 2 : HIGH 4, RH32-5, RH32-6, RH32-7 RHR-002 7' 20-RHR-32 RH32-8, RH32-9, RH32-10, RH32 . 14 NONE 18 - MEDIUM CAT 6 LOW l1, RID 2-12 RH32-13, RH32 "

RHR-003 5 20-RHR-33 RH33-15 RIU3-16.RH33-17, TT SMALL LEAK - 19 HiGH CAT 2 HIGH RH33-1S, RH33 RHR-004 6 24-RHR-28 RH28-25. kH28-24, RH28-23, 'N NONE 09,10 HIGH CAT 4 MEDIUM . ]

RH28-21 RH28-21, RH28-20 RHR-005 7 24-RHR-28 RH28-19, RH28-18. RH28-17 N NONE I1 ' LOW ' CAT 7 LOW '

"J128-16 RH28-15.RH28-14

^

RH28-12 RHR-006 6 24-RHR-29 RH29-19, RH29-18, RH29-17 N NONE 13,14 ' HIGH CAT 4 MEDIUM RH29-16, RH29-15. RH29-14 RHR-007 4 24-RHR-29 RH29-13. RH29-12, RH29-11, N NONE 15 LOW CAT 7 LOW RH29-10 RHR-008 5 24-RHR-30 RH30-8, RH30-7, RH30-6, RH30- N NONE 12 HIGH CAT 4 MEDIUM

$ RH30-5 RHR-009 4 24-RHR-30 RH30-4, RH30-3, RH30-1 RIDO-1 TASCS,TT SMALL LEAK 12 HIGH - CAT 2 HIGH RHR-010 1 24-RHR RH31-7 N NONE 16 HIGH CAT 4 - MEDIUM RHR-Oli 5 24-RHR-31 RH31-6, RH31-4, RH31-3, RH31- TT SMALLLEAK 16 HIGH CAT 2 HIGH 1 RH31-1.

12

__.___.m_,

.m. . . _ _._ .. ._..

I. _ _ _ _ _ _ _ . . _ _ _ _ _ . . -

1 Tr.bb 10 -

Sisa7 2:36:24 FMECA - Segment Risk Ranking Report oe. - la a n Number Degradation Mechanism . Co. ;;w;..cc Consequence . . Risk . Risk.

Segment ID of Welds Lines in Segment Welds in Segment Mechanisms - Cstegory ' ID(s) Category ' Category ~ Rank ~-

. RWCU-001 4 2-CUW-400 CU400-FI, CU400-FW2, CU400- N NONE 08 MEDIUM CAT 6- LOW FW3, CU400-FW4 RWCU-002 6 4-CUW CU18-10. CU18-9, CU18-8, CU18- N NONE 05 MEDIUM ' CAT 6 LOW --

7 CU18-6,CU18-5 RWCU-003 10 4-CUW-18 CU18-4, CU18-3, CU18-2, CUI8- N NONE 06 LOW. CAT 7 LOW 1,CU18-F13.CU18-F14 CU18-FIS,CU18-F16 CU18-FI7,CUI8- '

F18 RWCU-0CM 2 4-CtAV-18 CU18-F23.CU18-F25 N NONE 07 IIIGH : CAT 4 . MEDIUM.

13

= - - -

.- ----_____z _ . _ _ _ . - _ _ _ . _ . . ..,, . - . _ , . _ _ _ . . .. _ _._,_ - . .

l l

Table 11 I i

l Consoouonce ID I Cpnagguence ComNnhensegygnse Catocorv ' CCDP ~

Q1- RQCA _MfGH _6;00E R 02 LLOCA HIGH JQQ[-Q4 03 'AQCA MEDIUM. 800EfA5 Q1 MLOCA __JMEDIUM 8DQEf)5 ;

05 MLQCA tMEQiUM 8 00E.E 06 ILOCA _.JQW J00E-QZ 07 LOC &QC HIGH 4DQE:QS Q6_ MLOCA MEQl1VM 8.0DE-Q5 0? ISLQCA MGH 2.00E@

10 ISLOCA H1CH 2.00E-03 11 PLQCA (OW 1.00E-06 12 QQCA MGH 6.0QER 13 ISLOCA HIGH 2.00E-03

.lj ISLOCA HIGH 2.00E-03 15 ELQCA LOW 1.0Q[@

16 LLOCA HIGH 6.0QEB 17 LLOCA HIGH 6.00E 04 18 ILOCA MEDlVM 1.QQEB i 19 ISLOCA 4GH 1.00E-03 20 LLOCA MGH 6.OJE-04 I 21 ISLOCA HIGH 2.00E 03 22 PLOCA LOW 1.00E-06 7.3 QOCA HtGH 6.00EM 24 ISLOCA HIGH 2.00E-03 25 PLOCA LOW 1.00E-06 26 LLOCA HIGH 6.00E-04 2Z,,_,, LOCA-OC HIGH 2.00E-04 28 TFWMS MEDIUM 4.00E-05 29 LLOCA HIGH 6.00EG 30 LLOCA HIGH 6.00E-04 31 LLOCA HIGH 6.00E-04 32 LOCA-OC HIGH 2.00E-04 33 TFWMS MEDIUM 5.00E-05 34 LLOCA HIGH 6.00E-04 35 LLOCA MGH 6.00E 04 36 LLOCA HIGH 6.00E-04 37 LLOCA HIGH 6.00E-Od 38 ILOCA MEDIUM 4.00E-06 39 LOCA-OC MEDIUM 6.00E-06 40 LLOCA HIGH 6.00E&

41 ILOCA MEDIUM 4.00E-06 42 LOCA-OC MEDIUM 6.00E-06 43 LLOCA HIGH 6.00E-04 44 ILOCA MIDIUM 4.00E-06 45 LOCA-OC MEDIUM 6.00E-06 46 QOCA dQH _ 6.00E 04 47 ILOCA MEDIUM 4.00E-06 48 LOCA OC MEDlQM 6.00E-06 49 MLOCA MEDIUM 8.00E-05 50 ILOCA MEDIUM 4.00E-06 51 LOCA-OC MEDIUM S.00E-06 52 LLQCA HIGH 6.00E.Q4 53 ILOCA MEDIUM 3.00E 06 54 ILOCA MEDIUM 3.00E-06 55 SLOCA LQW 1.00Eg 56 MLOCA MEDIUM 8.00E-05

$7 PLOCA LOW 8.00E-08 58 LOCA<>C MEDIUM 1.00E @

50 SLOCA LOW 1.00E-06 60 LOCA-OC HIGH 6.00E-QS 61 TRAN MEDIUM 1.00E-05 42 SLOCA MEDill_M 1.00E-05 63 SLOCA LOW . 1.00E-06

^4 St OCA LOW 1.00E-06 PoGe 1

/. ,.

Table of Contents Sectl00 Page 1 . 0 1 N T R O D U C TI O N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.1 B a ck g ro u n d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Scope..............................................................................................................................5 1 . 3 As s u m p t io n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.0 I DENTI FICATIO N OF DAMAG E M ECH AN IS MS ............................. .. ............................... 7 3.0 REACTO R RE CI RCU LATIO N SYSTEM ......................... . ........... ............. ...... .................. 11 3.1 Reactor Recirculation System Description ................................................................... 11 3.2 Reactor Recirculation System Class 1 Boundary....................... ................................. 11 3.3 Reactor Recirculation System Weld Locations............................................................. 12 3.4 Reactor Recirculation System Degradation Mechanisms Evaluation...........................12 4 . 0 M AI N S T EA M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4.1 Main Steam (including Main Steam Drain, RCIC and HPCI) System Description........ 20 4.2 Main Steam, Main Steam Drain, RCIC and HPCI System Class 1 Boundary.............. 20 c

4.3 Main Steam, Main Steam Drain, RCIC and HPCI System Weld Locations.................. 22 4.4 Main Steam, Main Steam Drain, RCIC and HPCI System Degradation 1 M e ch a n is m s Evalu a tio n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .

5.0 M Al N F E E DWAT E R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

l' 5.1 Main Feedwater System Description ............................................................................ 35 5.2 Main Feedwater System Class 1 Boundary ................................................................. 35 5.3 Main Feedwater System Weld Locations ..................................................................... 36 5.4 Main Feedwater System Degradation Mechanisms Evaluation ................................... 36 6.0 R E SI D U AL H EAT RE M OVAL (RH R) .......................... ......... ............................ ................. 44 6.1 R H R S yste m D e scriptio n . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 6.2 RH R Syste m Cla ss 1 B ou nd a ry .... . . .... .. . . . . . .. . .... . .. . . ....... . . . . ... .... . .. . .. . .. .. ... . . . . . . .. . .... . . . .. . .. . 44 6.3 RH R System Weld Locatio ns .... . .. . .. . . . . .. .. . . . ... .... . . .. .. . . . ... .... . . . .. . .. . . . . . .. . . ... . .. . .. . . ... ..... . . .. . . . 4 5 6.4 RHR System Degradation Mechanisms Evaluation ..................................................... 45 7.0 C O R E S P RAY SYSTE M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7.1 C S S yste m D e scri ptio n . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 7.2 C S S ystem Cla ss 1 Bou nd a ry . .. .. .. . ..... . . . . .. .... . . . . .... ... ... ... .. . ... .. .. .. .. ... ... . . .. . ...... . .... . . . . .. . .. 52

7. 3 C S S yste m Weld Lo ca tio n s . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 7.4 Core Spray System Degradation Mechanisms Evaluation.............................. ............ 53 Revision: 8/6/97 !

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8.0 STAN D B Y L I O U I D C O N TR O L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .~ 58 8.1 S LC Syst em D e scriptlo d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., . . . .. . . . . . .

8.2 S L C Syste m Cla ss 1 Bou nd a ry . . . . . . . . . . . . . . . .. .. . . . . .. ... . . .. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. ... ..... . . .. . . . .. . . . 58 8.3 SLC System Weld Locations . . . . . . .... ... . . . . . ... ... .... . . . . .. . . . .... . . . . ... . . . . . . . . . . . . . . . . . . . . . .. .. . . . . . . .. . ... ... 58 8.4 SLC System Degradation Mechan!sms Evaluation ...................................................... 59 9.0 R EACTO R WAT E R C LEAN U P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 64 9.1 Reactor Water Cleanup System Description ................................................................ 64 9.2 Reactor Water Cleanup System Class 1 Boundary...................................................... 64 9.3 RWCU Syste m Weld Location s .. .. . .. . .. . .. .. . . . .. . . . . . . . .. . ... .. ... . .... .. .. . . . . . . ... . .. . ... ..... . . .. .. . ... ... . .. 6 5 9.4 RWCU System Degradation Mechanisms Evaluation.................................................. 65 1 0. R E F E R E N C E S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 0 APPENDIX A DEGRADATION MECHANISM EVALUATION FOR REACTOR R E C I R C U LATI O N SY STE M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . A-1 APPENDIX B DEGRADATION MECHANISM EVALUATION FOR MAIN STEAM, RCIC A N D H P C I S Y ST E M S . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .B-1 APPENDIX C DEGRADATION MECHANISM EVALUATION FOR MAIN FEEDWATER SYSTEM.........................................................................................................C-1 APPENDIX D DEGRADATION MECHANISM EVALUATION FOR RESIDUAL HEAT R E M OVAL SY STE M . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1 APPENDIX E DEGRADATION MECHANISM EVALUATION FOR CORE SPRAY SYSTEM.........................................................................................................E-1 APPENDIX F DEGRADATION MECHANISM EVALUATION FOR STANDBY LIQUID C O NT RO L S Y STE M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F- 1 APPENDIX G DEGRADATION MECHANISM EVALUATION FOR REACTOR WATER C L EAN-U P SY STE M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-1

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l' l t

List of Tables Iable Eaon Tcble 2-1 Degradation Mechanisms and Attributes in Code Case N-560 [1] .......................... 8 Tcble 2-2 Degradation Mechanism Criteria and Susceptible Regions in E PR I Ris k-lnformed Procedu re [33) ........ . .......... ... . . .. ...... . ........... . ........ .................... 9 Tcble 3-1 Reactor Recirculation Class 1 Lines and Operating / Design Conditions................12 Tcble 3-2 Weld Locations on Loop A Reactor Recirculation System.....................................16 Tcble 3-3 Weld Locations on Loop A Reactor Recirculation System.....................................18 Tcble 4-1 Main Steam /RCIC/HPCI Class 1 Lines and Operating / Design Conditions............ 21 Tcble 4-2 Weld Locations on Main Steam Loop A................................................................. 25 Tcble 4-3 Weld Locations on Msin Steam Loop B................................................................. 27 Tcble 4-4 Weld Locations on Maln Steam Loop C ................................................................ 29 Tcble 4-5 Weld Locations on Main Steam Loop D ................................................................ 31 Tcble 4-6 Weld Locations on HPCI Steam Supply ................................................................ 33 Tcble 4-7 Weld Locations on RCIC Steam Supply ................................................................ 34 Tcble 5-1 Main Feedwater Class 1 Lines and Operating / Design Conditions......................... 36 Tcble 5-2 Weld Locations on Main Feedwater Line A ........................................................... 4 0 Tcble 5-3 Weld Locations for Main Feedwater Line B ........................................................... 42 Tcble 6-1 RHR System Class 1 Lines and Operating / Design Conditions.............................. 45 Table 6-2 Weld Locations for Residual Heat Removal System (Line 20-RHR-32 -Suction).. 49 Table 6-3 Weld Locations for Residual Heat Removal Systern (Line 24-RHR Discharge).............................................................................................................50 Table 6-4 Weld Locations for Residual Heat Removal System (Line 24-RHR l- Discharge).............................................................................................................51 Tcble 71 CS System Class 1 Lines and Operating / Design Conditions ................................ 52 Tcble 7-2 Weld Locations for Core Spray System Loop A..................................................... 56 Tcble 7-3 Weld Locations for Core Spray System Loop B..................................................... 57 Tcble 8-1 SLC System Class 1 Lines and Operating / Design Conditions .............................. 58 Tcble 8-2 Weld Locations for Standby Liquid Control System............................................... 62 Tchle 9-1 RWCU System Class 1 Lines and Operating / Design Conditions .......................... 64 Tcble 9-2 Reactor Water Cleanup Weld Locations................................................................ 68 Revision: 8/6/97 Prepared By/Date:

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1.0 INTRODUCTION

1.1 Background

ASME Code Case N-560 [1] provides attemative examination requirements for Class 1, B-J piping welds in lieu of the requirements currently specified in Table IWB-2500-1 for such welds in ASME Code Section XI. The Code Case permits reduction in inspections from 25% to 10%

of Class 1 piping welds if thay are selected by risk-based precedures. The risk-based cpproach consists of two essential elements. The first part is the identification and evaluation of the degradation mechanisms that are associated with the piping system under 6- consideration. The seco7d aspect of the risk-based inspection approach is a consequence of failure evaluation to determine which portions of the piping system has the highest impact on plant safety. These two evaluations are used to determine the risk significant segments of the piping system that can be selected for inspection.

The purpose of this evaluation is to document the implementation of the degradation mechanism evaluation in Code Case N-560 to the Category B-J Welds at Vermont Yankee '

Nuclear Power Station. [1] The evaluation will include the identification of Class 1 piping systems (lines) and weld locations within those lines. Then, the lines will be evaluated for their susceptibility to degradation mechanisms identified in Reference 1.

1.2 Scope The following systems which comprise the Class 1 piping at Vermont Yankee are included in this evaluation. Tha Class 1 boundaries of these systems will be provided in the subsequent sections which identify the degradation mechanisms for each system.

Reactor Recirculation (Loo;'s A and B)

Main Steam (Lines A, B, C and D), including Main Steam Drain Main Feedwater(Lines A and B)

Residual Heat Removal Core Spray (Loops A and B)

Standby Liquid Control Reactor Water Cleanup The head vent piping system is attached to the reactor vessel with Nozzle N-7. Although a large part of the piping system is considered Class 1, the welds are excluded from the scope of the B-J Code Case as they are socket welds. Thus, this piping system is excluded from this evaluation.

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I As part of the procedure, the system boundaries and functions are identified. A risk evaluation is performed by selecting the Class 1 portion of the systems and identify the B-J weld locations within that system.

1.3 Aesumptions

1. System and system boundary identification is defined by the current ISI Program for Class 1, Category B-J Welds.

2. Degradation mechanisms are evaluated for systems within scope, based on conditions that occur during normal operation, including normal shutdown. Conditions which occur during, or as a result of an accident, are not considered in this assessment.

3. According to plant personnel, appropriate measures have been implemented to preclude the occt.rrence of water hammer at VY. [36) Thus, no systems are subject to the water hammer degradation mechanism.

4. No leakage occurs past containment isolation valves, because it is assumed that these valves have passed the requirements for containment leak tightness.

5. It is assumed that valves and other piping components do not allow air (oxygen) intrusion into the process fluid even underlong term stagnant conditions. If a system and/or section of piping is filled with primary grade water during startup or shutdown evolutions, the water quality is assumed to remain constant throughout the cycle.

6. The only location potentially susceptible to crevice corrosion is underneath thermal sleeves at the reactor vessel nozzle,

7. Nozzle to safe-end welds are classified as B-F welds and thus, are excluded from this cvaluation.

8. As documented in Reference 37, VY has implemented a Piping FAC Inspection Program that includes inspection of system locations susceptible to this degradation mechanism. Based upon inspection results, the only system that exhibits susceptibility is the Feedwater System, whereby nine locations are currently inspected as part of the FAC program, [38]

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2.0 IDENTIFICATION OF DAMAGE MECHANISMS Code Case N-560 [1] identifies several mechanisms that must be evaluated. These mechanisms are shown in Table 2-1 [1]. Of all the mechanisms identified in Table 2-1, only segments susceptible to FAC are classif;ed as resulting in a "large break". Segments susceptible to any other mechanisms are classified as "small leaks". Segments having degradation mechanisms listed in the small leak category are upgraded to the large break category if the pipe segments also have potential for water hammer.

As can be seen from Table 2-1, the attributes to the degradation mechanisms are quite a general. More specific guidance in the attributes to the degradation mechanisms has been provided in a companion risk-informed process developed under the auspices of the Electric Power Research Institute (EPRI)[35,40]. The degradation mechanisms and attributes under the program are shown in Table 2-2. As can be seen in comparing this table to Table 2-1, the listing of the degradation mechanism is similar between the Code Case and the EPRI cpproach. However, because more specific guidance is provided for the damage mechanism criteria in the EPRI approach, it will be used for the damage mechanism r, valuation in this evaluation. [35]

In the following sections of this calculation package, the degradation mechanisms and the criteria outlined in Table 2-2 are used to assess the potential active mechanisms for at the Class 1 systems listed in Section 1.2 for the Vermont Yankee Nuclear Power Plant.

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I B Table 2-1 Degradation Mechanisms and Attributes in Code Case N-560 [1]

Mechanism Attributes Susceptible Regions 1 Thermal Fatigue Intermittent Cold Water injection (1, ii, iii) Nozzles, branch pipe connections,

! 1. Thermal Shock Low Flow, Little Fluid Mixing (ii iii) safe ends, welds, HAZ, and base

11. Stratification Notch-Like Stress Risers (11, iii) metal regions of high stress 111. Striping Very Frequent Cycling (il, lii) concentration Unstable Turbulence Penetration into Stagnant Lines (ii, iii)

Bypass leakage in valves with large ATs (ii, lii) 2 Flow Accelerated Turbulent Flow at Sharp Radius Elbows and Tees Corrosion Proximity to Pumps, Valves and Orifices Material Chromium Content Fkiid pH Oxygen Temperature Erosion- Severe Discontinuities in Flow Path Fittings, welds, and HAZ Cavitation Proximity to Pump, Throttle Valve, Reducing Valve or Flow Odfice 4 Corrosion Aggressive Environment (i, iii) Base metal, welds, and HAZ

l. General Oxidizing Environment (il,lii)

Corrosion Material (1, Iv)

11. Crevice Temperature (1, Iv)

Corrosisn Contaminants (sulfur species, chlorides, etc.) (ii) 111. Pitting Crevice Condition (ii)

Iv. MIC Stagnant Region (ii)

Low Flow (iii)

Lay up (iv) 5 Stress Corrosion Susceptible Material (i) Austenitic stainless steel welds Cracking Oxidizing Environment (i,li) and HAZ (i) 1.IGSCC Stress (residual, applied)(1, li) Mill-annealed Alloy 600 nozzle

11. TGSCC Initiating Contaminants welds and HAZ without stress lil. PWSCC (sulfur species, chlorides, etc.) (i) relief (iii)

(aqueous halides or concentrated caustic) (ii)

Temperature (i,11)

Strain Rate (environmentally assisted cracking)(i, li)

Fabrication Practice (e.g., weld ID grinding, cold work (i)

Notch-like Stress Risers 6 Water Hammer Potential foIFluid Voiding and Relief Valve (Note (t)1 Discharge NOTE:

(1) Water hammer is a rare, severe loading condition as opposed to a degradation mechanism, but its potential at a location, in conjunction with one or more of the listed degradation mechanisms, could be cause for a higher examination zone ranking.

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i t Table 2-2 Degradation Mechanism Criteria and Susceptible Regions in EPRI Risk-Informed Procedure [35]

Degradation Criteria Susceptible Region Mechanism TF TASCS - nps > 1 inch, and nozzles, branch pipe connections, safe

- pipe segment has a slope < 45' from ends, welds, heat affected zones (HAZ),

horizontal (includes elbow or tee into a base metal and regions of stress vertical pipe), and concentration

- potential exists for low flow h a pipe section connected to a component allowing mixing of hot and cold fluids, or potential exists for leakage flow past a valve (i.e., in-leakage, out-leakage, cross-leakage) allowing mixing of hot and cold fluids, or potential exists for convection heating in dead +nded pipe sections connected to a source of hot fluid, or potential exists for two phase (steam / water) flow, or potential exists for turbulent penetration in branch pipe connected to header piping containing hot fluid with high turbulent flow, and

- calculated or measured AT > 50*F and

- Richardson number > 4.0 TT - operating temperature > 270*F for stainless steel, or operating temperature > 220*F for carbon steel, and

- potential for relatively rapid temperature changes including cold fluid injection into hot pipe segment, or hot fluid injection into cold Sipe segment, and AT : > 200'F for stainless steel, or AT ! > 150'F for carbon steel, or AT > AT allowable (applicable to both stainless and carbon)

SCC IGSCC evaluated in accordance with existing plant austenttic stainless steel welds and HAZ (BWR) IGSCC program per NRC Generic Letter 88-01 IGSCC - operating temperature > 200*F, and (PWR) - susceptible material (carbon content >

0.035%), and

- tensile stress (including residual stress) is present, and

- oxygen or oxidizing species are present OR

- operating temperature < 200*F, the attributes above apply, and

- initiating contaminants (e.g., thiosulfate, fluoride, chloride) are also required to be present-Revision: 8/6/97 Prepared By/Date:

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TGSCC - operating temperature > 150*F and

- tensile stress (including residual stress)is present, and

- halides (e.g., fluorido, chloride) are present, or caustic (NaOH)is present, and

- oxygen or oxidizing species are present (only required to be present in conjunction w/ halides, not required w/ caustic)

ECSCC - operating temperature > 150*F. and austenitic stainless steel base metal, tensile stress is present, and welds, and HAZ

- an outside piping surface is within five diameters of a probable leak path (e.g.,

valve stems) and is covered with non-metallic insulation that is not in compliance with Reg. Guide 1.36, or an outside piping surface is exposed to wetting from chloride bearing environments (e.g., seawater, brackish water, brine)

PWSCC - piping material is inconel (Alloy 600), and nozzles, welds, and HAZ without stress

- exposed to primary water at T > 620*F, and relief

- the materialis mill-annealed and cold worked, or cold worked nd welded without stress relief LC MIC - operating temperature < 150*F, and fittings, weids HAZ, base metal,

- low or intermittent flow, and dissimilar metal joints (e.g., welds,

- pH < 10, and flanges), and regions containing

- presence / intrusion of organic material (e.g., crevices raw water system), or water source is not treated w/biocidos (e.g., refueling water tank)

PIT - potential exists for low flow, and

- oxygen or oxidizing species are prescot, and

- initiating contaminants (e.g., fluoride, chloride) are present CC crevice condition exists (e.g., thermal sleeves), and

- operating temperature > 150*F, and

- oxygen or oxidizing species are present FS E-C - operating temperature < 250*F, and fittings, welds HAZ, and base metal

- flow present > 100 hrs /yr, and

- velocity > 30 ft/s, and

- (P,- P,) / AP < 5 FAC - evaluated in accordance with existing plant FAC program t

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, i 3.0 REACTOR RECIRCULATION SYSTEM 3.1 Reactor Recirculation System Description The reactor recirculation system provides forced circulation of reactor water through the core for core cooiing and flow distribution to all fuel channels.

Tha reactor recirculation systern consists of two loops extemal to the reactor vessel. Each loop has a variable speed recirculation pump which takes suction from the area between the shroud and reactor vessel and provides the driving flow of water to the reactor vessel jet pumps. Each extemalloop consists of a downcomer, a motor-operated pump suction valve, a high capacity motor-driven pump, a motor-operated pump discharge valve with a motor-operated bypass, a discharge riser containing a venturi-type flow meter and a ring header which supplies five jet pump risers.

Erch pump'provides the driving flow to 10 jet pumps (approxirnately 1/4 core flow at full power). The remaining 1/4 of reactor core flow for each loop is educted from the annular region between the shroud and the reactor vessel. The water is comprised of feedwater and retum water from the dryer and separators. The feodwater subcools the suction flow sufficiently to provide sufficient pump NPSH and prevent cavitation at hot power operation. [2]

Th3 recirculation system is affected by residual heat removalinitiation during shutdown cooling.

Th3 design flow for the recirculation pump is 32,500 gpm. The minimum flow is 1,000 gpm.

[31) 3.2 Reactor Recirculation System Class 1 Boundasy Th3 Class 1 portion of the reactor recirculation system starts at the reactor vessel nozzles (N1 A and N1B), then continues to include lines 28-PLR,22-PLR,12-PLR and 4-PLR, re-connecting to the reactor vessel at nozzles N-2A, N-2B, N-20, N-2D, N-2E, N-2F, N-2G, N-2H, N-2J and N-2K [3].

(The recirculation system branches to the residual heat removal (RHR) system. The RHR system is evaluated in Section 6.0.)

Tcble 3-1 lists the Class 1 lines within the reactor recirculation system and defires their operating and design conditions [4,5).

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l Table 3-1 Reactor Recirculation Class 1 Lines and Operating / Design Conditions une Pipe Pipe Pipe Design _

Design Op. Notes Number Size Thickness Material [4] Pressure [4] Temp. Temp.

[5] [4] (4) o 28-PLR 28(1) Line List SS-6* 1250 psig 575* 650' (1) Reactor Type 316L (2) - recirc. Is not listed in Ref. 5 (2) Per Ref. 25.

22-PLR 22 (1) Line List SS-6* - 1250 psig 575* 550* (1)"

Type 316L (2) (2)*

12-PLR 12(1) LineList SS-6* 1250 psig 575' 550' (1) "

Type 316L (2) (2) "

4-PLR 4 (1) Line List SS-6* 1250 psig 575' 550' (1) "

Type 316L (2) (2)"

Welded piping s) stems (12 inches in diameter or greater) with a pipe code SS-6 (1500 lb. stainless steel) and classification of Paragraph 1.1, are fabricated from stainless steel pipe per ASTM A-358, Class 1, Grade TP304 or TP316 [4). HowevercReference 4 was written prior to Reference 25, discussing the -

recirculation piping replacement program. Thus, it shall be assumed that these lines are composed of 316L.

From Reference 25, the Recirculation System is composed of Type 316L Stainless Steel.

3.3 Reactor Recirculation System Weld Locations Class 1 B-J weld locations for Loops A and B of the reactor recirculation system are included cs Table 3-2 and Table 3-3 [6, 7].

3.4 Reactor Recirculation System Degradation Mechanisms Evaluation The evaluation of the degradation mechanisms per the criteria in Table 2-2 for the recirculation system is presented in Appendix A. Highlights of this evaluation are provided below for all the mechanisms.

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.' l 3.4.1 ThermalFatigue (TF) 3.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS)

TASCS is not cons!dered to be applicable to the recirculation system (exclusive of cross-over, v:nt and drain lines) because there is no likelihood of mixing of hot and cold fluids arising from the low flow from a connecting pipe segment or leakage fiow past a valve. Even during st:rtup conditions, the rates of temperature change are low such that there should ba no stratification in the recirculation piping, in addition there is no potential for dead-ended pipe s:ctions connected to a source of hot fluid and there is no potential for turbulent penetration of a branch pipe connection.

3.4.1.2 Thermal Transients (TT)

The first weld (RR-A-D-13 for Loop A; RR-B-D-13 for Loop B) of the Recirculation System near the RHR connection is affected by the Thermal Transient (TT) during the RHR injection transient.

3.4.2 Stress Corrosion Cracking (SCC) l 3.4.2.1 Intergranular Stress Corrosion Cracking (IGSCC)

The Recirculation System is not affected by the IGSCC Degradation Mechanism due to the f ct that all welds have been classified as Category A per Reference 25.

3.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC)

The Recirculation System is not affected by the TGSCC Degrcdation Mechanism due to the tbsence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34].

3.4.2.3 Extemal Chloride Stress Corrosion Cracking (ECSCC)

The Recircefation System is not affected by the ECSCC Degradation Mechanism due to the f ct that the system is insulated with non-metallic insulation per Reg Guide 1.36 [5).

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I l

3.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The Recirculation System is not affected by the PWSCC Degradation Mechanism due to the f ct that this plant does not experience temperature conditions greater than 620'F and this system does not contain any inconel, f

3,4.3 Localized Corrosion (LC) 3.4.3.1 Microbiologically Influenced Corrosion (MIC)

The Recirculation System is not affected by the MIC Degradation Mechanism due to the fact that this system is exposed to an operating temperature greater than 150'F [5].

3.4.3.2 Pitting (PIT)

The recirculation system is not susceptible to pitting because there is no potential for low flow during operation (exclusive of vent and drain lines), in addition, initiating contaminants such as fluorides and chlorides are controlled to the EPRI Hydrogen Water Chemistry Guidelines (34].

3.4.3.3 Crevice Corrosion (CC)

The Recirculation System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to-safe end weld, a B-F weld, excluded from this evaluation.

3.4.4 Flow Sensitive (FS) 3.4.4.1 Erosion-Cavitation (E-C)

The Recirculation System is not affected by the EC Degradation Mechanism due to the absence of a cavitation source and due to the fact that the operating temperature is greater than 250*F [5].

3.4.4.2 Flow Accelerated Corrosion (FAC)

Because the recirculation system is composed of stainless steel (TP316L) it was excluded from Reference 37, assuming that it is resistant to FAC due to its high chromium content

(>5%). Thus, the recirculation system is not affected by the FAC Degradation Mechanism.

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3.4.5 Water Hammer From Reference 36, the recirculation system is not affected by the Water Hammer Degradation Mechanism.

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MUMmm l

1 Table 3-2 Weld Locations on Loop A Reactor Recirculation System System Line Weld Weld TF SCC LC FS ID Number Number Location TASCS TT IGSCC TGSCC ECSCC PWSCC nflC PIT lCC E-C FAC RR-A-S-1 Downstream of Reactor Vesset Nozzle N-1 A. N N N N N N N N N N N RECIRC 28-PLR Upstream of Branch Connec5cn to 20-RHR-32 RR-A-S-2 Downstream of Reactor Vessef Nozzle N-1A, N N N N N N N N N N N RECIRC 28-PLR Upstream of Branch Connection to 20 RHR-32 RR-A-S-3 Downstream of Bra d1 Connectien to 20-RHR-32, N N N N N N N N N N N RECIRC 28-PLR Upstream from Va!ve V43A Upstream side of Valve V-43A, N N N N N N N N N N N RECTRC 28PLR RR-A-S-4 Dcwnstream of Branch Conrcetion to 20-RHR-32 RR-A-S-S Downstream side of Valve V-43A. N N N N N N N N N N N RECIRC 28-PLR Upstream from Pump P-18-1A N N N N N N N N N N N REC!RC 28-PLR R A-S-6 Downstream of Vafve V-43A.

Upstream from Pump P-18-1A RECIRC 28-PLR RR-A S-7 Upstream side of Pump P-18-1A N N N N N N N N N N N~

Downstream side of Pump P18-1A N N N N N N N N N N N RECIRC 28-PLR RR-A-D-8 RR-AB 1 Branch Connection to 4" PLR, N N N N N N N N N N N RECIRC 28-PLR Downstream from Pump P-1 A Upstream side of Valve V-53A, N N N N N N N N N N N RECIRC 28-PLR RR-A-D-9 Downstream of Brans Connection to J' PLR Downstream side of Vatve V-53A N N N N N N r4 N N N N RECtRC 28PLR RR-A-D-10 Downstream of Branch Connection from 4* PLR, N N N N N N N N N N N RECIRC 28-PLR RR-A-D-12 Upstream of Branch Connection to 24* RHR-30 Downstream of Branch Connection to 24" RHR40 N Y N N N N N N N N N RECIRC 28-PLR RR-A-D-13 Upstream from Branch Cornsction to 22" PLR Common Header for injection Nozzles N N N N N N N N N N N l RECIRC 22-PLR RR-RH-A-2 Upstream frorn Nozzle N-2J N N N N N N N N N N N RECIRC 12-PLR RR-N2J-1 Upstream from Nozzle N-2J N N N N N N N N N N N RECIRC 12-PLR RR-N2J-2 RR-RH-A-1 Common Header for injection Nozzles N N N N N N N N N N N RECIRC 22-PLR Upstream from Nozzle N-2K N N N N N N N N N N N RECIRC 12-PLR RR-N2K-1 RR-N2K-2 Upstream frorn Nozzle N-2K N N N N N N N N N N N RECIRC 12-PLR Upstream from Nozzle N-2H N N N N N N N N N N N REC!RC 12-PLR RR-N2H-1 Upstream from Nozzle N-2H N N N N N N N N N N N l RECIRC 12-PLR RR-N2H-2 I Common Header forinjection Nozzles N N N N N N N N N N N RECIRC 22-PLR RR-RH-A-3 Upstream from Nozzle N-2G N N N N N N N N N N N RECIRC 12-PLR RR-N2G-1 Upstream from Nozzle N-2F N N N N N N N N N N N RECIRC 12-PLR RR-N2F-2 e "

.r. . . . . . -- .. .. .. -

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Table 3-3

! Weld Locations on Loop B Reactor Recirculation System System Larse 9FnM 99wd TF SCC LC F5 10 Number Number Loca6ert TASCS TT XsSCC TGSCC ECSCC P9V5CC nNC PfT - CC E-C (FAC REORC 28-PLR RR-B-S-1 Downstream of Reactor Vessel Nozzle N-1B N -N' N N N N N :N N N lN REORC 26PLR RR-B-S-2 Doumstream of Reacsor Vessel Nozzle N-1B N N qN N N N N N N N N RECRC 2SPLR RR-B-S-3 Downstream of Reactor Vessel Puazzle N-1B N N -N N N jN N N N N N REGRC 28-PLR RR-B-S-4 Upstream side d Valve V438 q N N N N N 'N N (N N .N N REQRC 28-PLR RR-B-S-5 Downstream side of Vahe V-43B N N N N N N N N N N -N REQRC 28-PLR RR-B-S4 Upstream side of Ebow, N N N N N N N N N N N Downstream from Vatre V-438 REQRC 28-PLR RR-B-S-T Upstream side of Pump P-18-1R N N N N N N N N N N N RECtRC 28-PLR RR-B O-8 Downstream side of Pump P-18-1B N N N N N N- -N N N N N REORC 28-PLR RR-BB-1 Branch Co mecson to 4* PLR N N N N N N N N N N N

- RECRC 28-PLR RR-B-D 9 Upstream sede of Vatwe V-53B N N N N .N N N N N N N RECRC 28-PLR RR-0-&10 Duwnstream sees of Valve V-538 N N N N N N N N N N N RECRC 2SPLR RR-B O-11 Downstream et Branch Connecnon from 4* PLR N ,N N N N N N N N 'N N REORC 28-PLR RR-B 0-12 Upstream of Branch Connechon to 24* RHR-31 N N N N N N N .N N N N REORC 28 PLR RR-B-D-13 Downstream of Brar'ch Corum to 24* RNR-21 N Y N ljN N N N N N N N REQRC 22-PLR RR-RH-B-2 Corrmon Header for Infecton Nozzles N N N :N N N N N N N Po REQRC 12-PLR RR442D-1 Ocwnstream of Braretti Connechon to 22" PLR, N N N N N N N N N N N Upstream from Nozzle N-2D REGRC 12-PLR RR-N242 Upetream from Nozzle N-2D N N .N N N N N N lN LN ,N REGRC 22-PLR RR-RH-B-1 Commort Header for letec2 ion Nozzles N N N N N N N ,N N N N REOF :12-PLR RR-N2E-1 Downstream of Branct Connecton to 22" PLR. N N N N N N N N N N N Upstream tom Nozzle N-2E RECRC 12-PLR RR-N2E-2 Upstream from Nozzle N-2E N N N N N N N .N N N N

REQRG 12-PLR RR-N2C-1 Downstream of Brandt Connecmon to 22" PLR. N N N N N N N N N gN N

Up.e Nozzie u-2C REGRC 12-PLR RR-N2C 2 Upstream from Nozzle N-2C .N N N N N N N N N N N j REQRC 22-PLR RR-Rt+8-3 Common Header ftv Injecton Nozzles N N N N N N 'N N N N N REGRC 12-PLR RR-N28-1 Downstream of Brandt Connecton to 22" PLR, N N N N N N N N N N N Upstream from Nozzle N-2B l REORC 12-PLR RR-N28-2 Upsteam from Nozzle N-2B N !N N N N N N iN N N N l

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4.0 MAIN STEAM 4.1 Main Steam (including Main Steam Drain, RCIC and HPCI) System Description Steam exits from the vessel several feet below the reactor vessel flange through four nozzles (N3A, N38, N3C and N3D) Carbon steel steam lines are welded to vessel nozzles, and run p rallel to the vertical axis of the vessel, downward to the elevation where they emerge from the containment. Two air-operated isolation valves are installed on each steam line, one inboard and one outboard of the primary containment penetration. The safety-relief valves are f1:nge-connected to the main steam line for ease of removal for test and maintenance [S).

A flow restricting nozzle is included in each steam line as an additional engineering safeguard 4

to protect against a rapid uncovering of the core in case of a break of a main steam line [32].

Steam supply lines are provided for reactor core isolation cooling (RCIC) and high pressure coolant injection (HPCI) systems. The RCIC system consists of a turbine driven pump unit utilizing reactor steam pressure capable of injecting makeup water into the vessel via the fredwater line at a rate of 400 gpm throughout a reactor pressure range of 150 to 1120 psig.

Upon reactor shutdown and vessel isolation and complete loss of offsite power, the pumping capacity of the RCIC is sufficient to maintain water level above the core without any other makeup system in operation [9].

The HPCI system consists of a turbine-driven pump assembly which utilizes reactor steam to pump water into the vessel via the feedwater line at the rate of 4250 gpm over a reactor pressure range of approximately 150 to 1120 psig. [10] The HPCI system is designed to provide emergency core cooling in the event of a failure in a small process line, without reliance on station auxiliary power supplies other than the dc power supply. Because of the limited flow rate from a small line failure, it is possible that water level in the vessel could be reduced to a point where core cooling would be impaired without significantly reducing the pressure in the vessel. Under such conditions, the Core Spray, or LPCI system, or both, would not be able to inject coolant into the vessel. The HPCI system, therefore, is designed to pump water into the vessel while it is fully pressurized and will provide adequata cooling until reactor pressure drops sufficiently to enable the core spray system and the LPCI system to be placed in operation.

4,2 Main Steam, Main Steam Drain, RCIC and HPCl System Class 1 Boundary The Class 1 portion of the main steam system starts at the reactor vessel nozzles (N-3A, N-3B, N-3C and N-3D), then continues to include lines 18-MS-7A (Loop A), -78 (Loop B), -7C Revision: 8/6/97 Prepared By/Date:

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4

! (Loop C),and -7D (Loop D). [3,11,12] It should be noted that the one high pressure coolant I

injection (HPCI)(10-MS 4A)line attaches to the Loop B main steam line and is included within the Class 1 Boundary, ending at Valve MOV 23-10. Also, one reactor core isolation cooling (RCIC)line (3-MS-5A) attaches to the Loop C main steam line and is included within the Class 1 Boundary, ending at Valve V1316 [11,12,26]. The following provides a detailed d:scription of the Class i bouridary for each of the main steam loops:

o For Loop A, the Class 1 boundary ends at Valve V-86A.

o For Loop B, Line 18-MS-7B (the Class 1 portion of this line ends at Valve V2-868/ penetration X-7B) branches off to include Line 10-MS-4A, ending at Valve MOV 23-

16. Line 10-MS-4A is part of the HPCI system.

o For Loop C, Line 18-MS-7C (the Class 1 portion of this line ends at Valve V2-86C/ penetration X-7C) branches off to include Line 3 MS-5A, ending at Valve V13-16.

Line 3-MS 5Ais pariof the RCIC system.

o For Loop D, the Class 1 boundary ends at Valve V2-86D.

Table 41 lists the Class i lines within the main steam systern and defines their operating and design conditions [4,5).

Table 4-1 Main Steam /RCIC/HPCI Class 1 Lines and Operating / Design Conditions Line Pipe Pipe Pipe Design Design Op. Notes Number Diameter Thickness Material Pressure Temp. Temp.

[4, 5. 26] [4. 26] [4, 5, 26] [4,26] [4. 26] [5]

18-MS 7A 18" Sch.80 CS5* 1250 psig 575* 547*

18-MS 78 18" Sch.80 CS-5* 1250 psig 575* 547*

18-MS 7C 18" Sch.80 CS 5* 1250 psig 575* 547*

18-MS 7D 18" Sch.80 CS-5* 1250 psig 575* 547*

10-MS-4A 10" (1) Sch.80 CS-5* 1250 psig 575* 550' HPCI

1) Ref. 5 states MS-4 3-MS-5A 3" (2) Sch.160 C S-5* 1250 psig 575* 550' RCIC

2) Ref. 5 states MS-5 2-MSD-2 2" (3) Sch.160 CS 5* 1250 psig 575* 550' 3) Ref. 5 states MSD - (2" &

smaller) 3 MSD-2 2" (4) Sch.160 CS-5* 1250 psig 575* 550' 4) Ref. 5 states MSD - (2" &

smaller) 1 1/2MSD-421 1 W (5) Sch.160 CS-5* 1250 psig 575* 550' 5) Ref. 5 states MSD - (2" &

smallor)

Piping systems (24 inch nominal diameter and less) with a pipe code CS-5 (900 lb cart >on steel) and classification of Paragraph 1.1, are fabricated from carbon steel per ASTM A-106, Grade B [4).

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4.3 Main Steam, Main Steam Drain, RCIC and HPCI System Weld Location's CI:ss 1 B-J weld locations for Main Steam Loops A, B, C and D, HPCI, and"RCIC are included cs Tables 4-2 through 4-7 [7,11,12].

4,4 Main Steam, Main Steam Drain, RCIC and HPCl System Degradation Mechanisms Evaluation The evaluation of the degradation mechanisms per the criteria in Table 2-2 for the main st:am, HPCI, and RCIC systems are presented in Appendix B. Highlights of this evaluation i ara provided below for all the mechanisms.

4.4.1 ThermalFatigue (TF) 4.4.1.1 Thermal Stratificotton, CycIlng, and Striping (TASCS)

The Main Steam, RCIC and HPCI Systems are not affected by the TASCS Degradation M:chanism due to the fact that they are (normally) filled with steam and no TASCS m:chanism can occur.

The Maln Steam Drain System is affected by the TASCS Degradation Mechanism due to the f ct that the potential exists for two phase flow of steam and water in this system during

, st^rtup as this normally steam-filled system collects condensate water during this transient.

4.4.1.2 Thermal Transients (TT)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the thermal tr:nslent (TT) Degradation Mechanism due to the absence of rapid temperature changes from cold / hot injections from rapid transient events. It should be noted that although the Main Steam system is not affected by thermal fatigue, the Main Steam System could be affected by mechanical fatigue due to the MSRV actuation.

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Checked By/Date:

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/

4.4.2 Stress Corrosion Cracking (SCC) 4.4.2.1 Intergranular Stress Corrosion Cracking (IGSCC)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the IGSCC Degradation Mechanism due to the fact that the piping is composed of carbon steel (A-106, Grade B), a material that is not susceptible to IGSCC.

4.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34).

4.4.2.3 Extemal Chlande Stress Corrosion Cracking (ECSCC)

The ECSCC Degradation Mechanism are not applicable to the Main Steam, Main Steam Drain, RCIC and HPCI Systems due to the fact that these systems are composed of carbon steel (A-106, Grade B) [4].

l l 4.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC) l The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the PWSCC Degradation Mechanism due to the fact that this plant does not experience temperature conditions greater than 620'F and this system does not contain any inconel.

4.4.3 Localized Corrosion (LC) 4.4.3.1 Microbiologically Influenced Corrosion (MIC)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affect by the MIC Degradation Mechanism due to the fact that these systems are exposed to an operating l temperature greater than 150*F [5).

4.4.3.2 Pitting (PIT)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the PIT Degradation Mechanism due to the fact that these systeir.s are not exposed to low flow conditions and to PIT Initiating contaminants, as VY complies with EPRI Water Chemistry Guldelines [34].

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/ Checked By/Date:

File No. EPRI-116-301 Page 23 of 73

4.4.3.3 Crevice Conosion (CC)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the only location susceptible to CC is underneath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to-safe end weld, a B-F weld, excluded from this cvaluation.

4.4.4 Flow Sensitive (FS) 4.4.4.1 Erosion-Cavitation (E-C)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are not affected by the Erosion

-Cavitation (EC) Degradation Mechanism due to the absence of a cavitation source and due to the fact that the operating temperature is greater than 250*F [5].

4.4.4.2 Flow Accelerated Corrosion (FAC)

The Main Steam, Main Steam Drain, RCIC and HPCI Systems are a part of VY's FAC program

[37). As discussed in Section 1.3, program results have indicated that these systems are not susceptible to FAC [38).

4.4.5 Water Hammer From Reference 36, the Main Steam, Main Steam Drain, RCIC and HPCI systems are not cffected by the Water Hammer Degradation Mechanism.

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File No. EPRI-I16-301 Page__14__of 73

Table 4-2 Weld Locations on Main Steam Loop A Weid TF SCC LC FS System LJoe WeM 10 Number Number Lacedon TASCS TT IGSCC TGSCC E%CC PWSCC MC FTT CC EC FAC N N N N N/A N N N N N MA MS 18-MS-7A MS7A-N3A-SW Downstream side of Reactor Vessel Nozzle N-3A N N N N N/A N .N N N N MA MS 18-MS-7A MSTA-A8 Downstream of Reactor Vessel Nozzle N-3A MS7A,A7D N N N N N/A N N N N N .N/A MS 18-MS-7A Downstream of Reactor Vessel Nozzle N-3A N N N N N/A N N N N N N/A MS 18.MS-7A MSTA-A7C Downstream of Reactor Vessel Nozzle N-3A Downstream of Reactor Vesse Nozzle N-3A, N N N N MA N N N N N N/A MS 18-MS-7A MS7A-A7B Upstream from Spring Hangers MS-1 and MS-2 Downstream of Reactor Vessel Nozzle N-3A, N N N N MA N N N N N N/A MS 18-MS-7A MS7A A7A

- Upstream from Spring Hangers MS-1 and MS-2 Upstream from Spring Hanger MS-1 and MS-2 N N N N MA N N N N N NA MS 18-MS-7A MSTA AT Downstream from Spnng Hanger MS-1 and MS-2 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A6B hne wT. from Spring Hanger MS-t and MS-2 N N N N N/A N N N N N N/A MS 18-MS-7A MS7AA6A N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A8 Upstream side of Elbow, Upstream from Flange and Reuef Valve RV2-71A Downstream side of Elbow, N N N N N/A N N N N N N'A MS 18-MS-7A MS7A A5K Upstream from Flange and ReEef Valve RV2-71 A N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-ASH Rehef Valve RV2-71A N N N N N/A N N N N N N/A MS 18-MS-7A MSTA-ASI Retef Vafve RV2-71A N N N N N/A N N N N N MA MS 18-MS-7A MS7A-A5J Relief Vafve RV2-71A N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A5G Safety Valve SV-2-70A N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-ASF Safety Valve SV-2-70A Safety Vafve SV-2-70A N N N N N/A N N N N N .MA MS 18-MS-7A MS7A-ASE N N N N N/A N N N N N N/A MS 1tMAS-7A MS7A-A50 Flange Weld,

! @Le r.of Spring Hanger MS-5 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-ASC Flange Weld,

@LeT. of Spring Hanger MS-5 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-ASB Flange Weld, Upstream of Spring Hanger MS-5 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-ASA Upstream side of Elbow, h stream of Spring Hanger MS-5 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A5 Downstream side of Elbow, L etream of Spring Hanger MS-5 N N N N N/A N N N N N MA MS 18-MS-7A MSTA-A11 Upstream side of Elbow, Downstream of Snutter MS-6 N N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A4A Downstream side of Elbow, h 6tream of Snubber MS-6 N/A N N N N N/A N N N N N ,.

MS 18MS-7A MSTA-A4 Upstream side of Main Steam isolation Valve V2-80A N N N N/A N N N N N N/A MS 18-MS-7A MS7A-A3 Downstream side of Main Steam isolaton Valve V2- N 80A .

.i Table 4-2 Cont.

Syssen LJne IMWW Opsti TF SCC LC FS ,,

SD Number Number Lacedon TASCS TT GSCC TGSCC ECSCC 99VSCC BNC PfT CC EC FAC MS- 18-MS-7A MS7A-A9A Doumsteem sMe of Peneraton X-7A N N N N NA N N N N N NA MS 18-MS-7A MSTA-A9 Upeteem sede of Main Steam isolaton Vafve V2- N N N N NA N N N N N NA ~-

! 06A, Doumstroom from Peneta6on X-7A i

MSD 4-MSD-2A MSD2A-F1 Doum Brandi Connecton to 2* MSD from V2-80A ' Y- N N N NA N N N .N N NA MSD 2-MSD-2A MSD2A-F2 2" Brandi Connecton from V2-80A Y N N N NA N N N N N NA MSD 244SD-2A : MSD2M3 Downsteam from V26 Y N N N NA N N N N N NA MSD 2-MSD-2A MSD2A-F4 Doumsteem frorn V2-80A Y N N N NA N N N N N WA

! MSD 2-MSD-2A MSD2A-F5 Doomsteem from V2-80A Y N N N NA N N N N N NA 7

MSO 2-MSD-2A MSD2A-F6 Upseroom from Reduoer Y N N N NA N N N N N NA

, MSD 2-MSD-2A MSO2A-F7 Upsteam from Reducer to 3* MSD-2 Y N- N N NA N N N N N NA MSD 2-MSD-2A MSO2A-F8 Upstream sMe of Reducer to 3* MSD-2 Y N N N NA N N N N N NA MSO- 3-MSD-2 MSD2-S1 Doumstroem of V2-80A at Reducer to 3" MSD-2 Y N N N NA N N N N N NA I

1 i

1 I

r t

t f

f r

s y 9

< t 2

i f

a I

r f

,{ I g 1 5

, s., ,.

I

TEble 4-3 Weld Locations on Main Steam Loop B l Systern Une Weed Wood TF SCC LC '

FS Number Loceffort TASCS TT IGSCC TGSCC ECSCC PWSCC nFIC PIT CC EC FAC ID Number Downstream side of Reador Vessel Nozzle N-30 N N N N N/A N N N N -N N/A MS 18-MS-78 MS78-N33-SW Downstream of Reactor Vessel Nozzle NM N N N N N/A N N N N N MA MS 18-MS-78 MS78-88 Dr. mstream of Reactor Vessel Nozzle N3-8 N N N N N/A N N N N .N N/A MS 18-MS-78 MS78-87D Downstream of Reactor Vessel Nozzie N3-8 N N N N N/A N N N N N N/A MS 18MS-7B MS78-87C Downstream of Reactor Vesset Nozzle N3-B N N N N N/A N N N N N N/A MS 18-MS-78 MS78-878 Upstream of Spring Hangers MS-12 and MS-13 N N N N N/A N N N N N MA j MS 18-MS-78 MS78-87A Upstream of Spring Hangers MS-12 and MS-13 N N N N MA N N N N N N/A l MS 1MS-78 MS76-87 J Upstream of Spring Hangers MS-12 and MS-13 N N N N N/A N N N N N MA MS 18-MS-78 MS7B-B6D D-mLw w of HPCI Branch Une N 7 N N N/A N N N N N iN/A MS IntS-TB MS78-86C Downstream of HPCI Branch Une N N N N N/A N N N N N LMA MS 18 # S-78 MS78-868 Dowr stream of HPCI Branch une. Upstream of RV2-71B N N N N iWA 'N N N N N N/A MS 18-MS-7B MS7B-86A Downstream of MPCI Bra @ Une. Upstream of RV2-718 N N N N N/A N N N N N N/A MS 18-MS-78 'AS78-88 Downstream side of Elbow. Upstream from RV2-718 N N N N N/A N N N N N N/A MS 18-MS-78 MS78-85H IJpstream of RV2-718 N N N N N/A N N N N N N/A MS 1MS-78 MS78-BSG Upstream of RV2-718 N N N N N/A N N N N N N/A MS 18-MS-78 MS78-85F Upstream of RV2-71B N N N N N/A N N N N N N/A MS 18-MS-78 MS7B-B5E Reht' Valve RV-718 N N N N N/A N N N N N N/A MS 18-MS-78 MS78-BSD N N N N N/A N N N N N N/A MS 18-MS-78 MS7B-85C Renef Valve RV418 N N N N N/A N N N N N N/A MS 18-MS 78 MS78-BSB ReNef Valve RV-718 Upstream side of Eibow. N N N N N/A N N N N N N/A MS 18 # S-78 MS78-85A C-me o&T. from Spring Hanger MS-14 N N N N N/A N N N N N MA MS 18-MS-78 MS78-85 Downstream side of Elbow.

C-mL w.L from Spring Hanger MS-14 Upstrearn skie of Elbow. N N N N N/A N N N N N MA MS 18-MS-7B MS78-811 Downstream from Snubber MS-15 N N N N MA N N N N N N/A MS 18-MS-78 MS78-84C Downstream side or Elbow.

Downstream of Snubber MS-15 N N N N N/A N N N N N N/A MS 18-MS-7B MS78-848 Downstream of Elbow.

Upstream frorn Restraint MS-16 N N N N N/A N N N N N N/A MS 18-MS-78 MS78-B4A Downstream of Eibow.

Upstream from Restraint MS-16 N N N N N/A N N N N N N/A MS 18MS-78 MS7B-B4 Upsteam side of Main Steam isotatinn valve V2-800 N N N N N/A N N N N N MA MS 18-MS-78 MS78-83 Downstream side of Main Steam isolation Valve V2-80B N N N N N/A N N N N N N/A MS 18-MS-78 MS78-89A Downstream side of Penetration X-78 Upstream side of Maen Steam isotason Vafve V2-868 N N N N N/A N N N N N MA MS 18-MS-7B MS78-89 C-mLo.m of Penetration X-7B Y N N N N/A N N N N N NA eMSD 2-MSD-28 M m m-F1 2" Branch Connection from V2-808 Y N N N MA N N N N N N/A MSD 2WSD-26 MSD28-F2 Downstream from V2-808 *~

Y N N N MA N N N N N MA MSD 2MSD-2B McMR-F3 Downstream from V2-808 Y N N N N/A N N N N N N/A MSD 2-MSD-2B MSD28-F4 Downstream from V2-808 Y N N N N/A N N N N N N/A MSD 2-MSD-2B MSD28-F5 Downstream from V2-800 -

Y N N N N/A N N lN N N N/A MSO 2-MSD-28 Msrna-F6 Downstream from V2-809

l Table 4-3 Cont. .

Syssuun Une ~ Itlukt WMont TF SCC LC FS ,,

60 Nunnber Nunbar Locenen TASCS TT DGSCC TGSCC ECSCC PWSCC MC MT CC EC FAC MSO 2-MSD 2B MSD2Bf7 Doumetroom imm V2-808 Y N N N NA N N N N N MA MSD 2-MSD-28 MbO2EM7A Douvrasteem of V240B Y N N N lMA N N N N N NA ,

MSD 2-MSD-2B - MSD2Bf78 Doumsteem of V240B Y N N N NA N N N N- N WA MSD' 2-MSD-2B MSD2Bf7C Downsteem of V2408 Y N N N WA N N N N N WA MSD 2-MSD-28 MSG 2Bf7D Doesnsteem of V2-80B Y N N N MA N N N N N NA MSD 262B MSO2Bf7E Douunsteem of V2-800 Y N N N MA N N N N N NA MSD 2-MSD-2B ASD28-F7F - Dornsteem of V2-808 Y N N N WA N N N- N N MA MSD 2-MSD-28 MSO2B-F8 Clunsteem of V2-80B Tee Connecton from MSD2B to 3*. Y N N N NfA N N N N -N WA MSS 2 MSD 3-MSD-2 MSD2-S2 - Downsteem of V2-80A and V2-80C, Y N N N MA- N N N N N N/A At Brandi Connedlan b Penetragon X4 MSO 1.544SD-422 MSD422-F1 Upsteem of Branct Connocean from 3* MSD-2 Y N N N MA N N N N N WA MSD 1.5-MSD422 MSD422+2 Dousnotroom skse of Ebour, , Y N N N MA- N N N N N WA Upsteem of Brancit Connedian from 3* MSD-2 MSO 1.5-MSD-422 MSD422-F3 Upsteem skse of Ebow. Y N N N N/A N N N N N NA Upsteem of Brandt Connedion from 3* MSD-2 MSD 1.5-MSD442 MSD422-F4 Douunsteem of Tee Connecton to MSD420/421 Y N N N MA N N N N N WA MSD 1.'M4SD-420 MSD420-F9 Upsteem of Tee Connecaon on MSD420 Y N N N N/A N N N N N N/A MSD 1 SMSD-420 MSD420-F8 Upsteem of Tee Connecton on MSD-420 Y N N N WA N N N N N MA MSD 1.5-MSD-420 MSD42M7 Douunsteem side of Reducer on MSO-420 to 1* MSO Y N N N N/A N N N- N N NA MSD 1.5-MSD421 MSD42149 Upsteem of Tee Connecton on MSD-421

Y N N N WA N N N N N WA MSO 1.5-MSD-421 MSD42148 Upsteem of Tee Connecton on MSD421

Y N- N ,N N/A N N N N N N/A MSO 1.5-MSD421 MSO42147 Doumstream side of Reducer on MSD421 to 1* MSD

Y N N lN N/A N N N N N MA

Not included in R;';.s,ce 7.

t

Table 4-4 Weld Locations on Main Steam Loop C System Une Wekt Wekt l TF SCC LC 1 FS TASCS YT IGSCC TGSCC ECSCC PWSCCMIC PfT CC EC FAC ID Number Number Location N N N N N/A N N N N N MA MS SMS-7C MS7GN3C-SW Downstream side of Reactor Vessel Nozzie N-3C N N N N N/A N N N N N N/A MS 1MS-7C MS7CC8 Downstream of Reador Vesset Nozzle N-3C N N N N N/A N N N N N N'A MS 18-MS-7C MSTC C7D C- .L s.Hi d Reactor Vessel Nozzle N-3C N N N N N/A N N N N N N/A MS 1MS-TC MS7C C7C Downstream of Reactor Vessel Nozzle N-3C N N N N N/A N N N N N N/A MS 18-MS-7C MS7C-C7B Upstream sPJe of Ebow.

C-oLeon of Reactor Vessel Nozz!e N-3C N N N N N/A N N N N N N/A t MS 1MS-7C MSTC-C7A Downstream s6de of Elbow.

Dv iistream of Reactor Vessed Nozzle N-3C N N N N N/A N N N N N MA MS 18-MS-7C MS7C C7 Dovmstreamof Elbow Upstream from Vmc" Vent Line N N N N FWA N N N N N N/A MS 1pS-7C MS7C@ Vent une Weld N N N N MA N N N N N MA MS 18 MS-7C MS7C C6C Upstream side of Elbow.

Cw M.;from VW Vent une N N N N N/A N N N N N MA MS 18-MS-7C MS7CC6B Downstream side of Elbow.

C-stream from Vessel Vent Une N 'A N N N N N/A N N N N N MS 18-MS-7C MS7CC6A Downstream of Spring Hangers MS-21 and MS-22 Downstream of Spring Hangers MS-21 and MS-22 N N N N N/A N N N N N .MA MS 18-MS-7C MS7C C6 N N N N N/A N N N N N MA MS 18-MS-7C MS7C-C5K Downstream of Spring H.vcw MS-21 and MS-22 N N N N WA N N N N N re/A MS 18-MS-7C MS7CC5H Upstream from Spring Hanger MS-23 N N N N N/A N -N N N N MA MS 1844S-7C MS7CC54 Upstream frtrn Spring Hanger MS-23 N N N N N/A N N N N N MA MS 18-MS-7C MS7CC5J Upstream from Spring Hanger MS-23 N N N N N/A N N N N N MA MS 18-MS-7C MS7CC5G Urstream from Spring Hanges MS-23 N N N N N/A N N N N N N/A MS THAS-7C MS7C-CSF Upstream from Spring 6w MS-23 N N N N WA N N N N N NA MS 1MS-7C MS7C-CSE Upstream from Spring Hanger MS4'3 N N N N N/A N N N N N !N/A MS 1MS-7C MS7C C58 Rehef Valve RV2-71C MS7C CEC Renef Vane RV2-71C N N N N N/A .N N N N N [N/A MS 18-MS-7C N/A N N N N N/A N N N N N MS 1TrMS-7C MS7GC50 Relief Vane RV2-71C N N N N MA N N N N N MA MS 184.1S-7C MS7C-CSL Branch Connechon Weld to RCIC Steam Supply N N N N WA N N N N N MA MS 1 MAS-7C MS7CCSA Upstream side of Dbow.

Cv.-~L si fmm Spring H.vci MS-23 N N N NA N N N N N N/A MS7C C5 Downstream sade of Ebow. N MS 18-MS-7C C stream from Spring ver MS-23 N MA N N N N N/A N N N N MS 18-MS-7C MS7C C11 Downstream of Snubber MS-24 Uge T. from Restraint MS-25 N N N N/A N N N N N/A N N ,

MS 1MS-7C MS7C-C4C Upstream from Restraint MS-25 N N N N/A N N N N N N/A MS7C-C48 Upstream fmm Rrsstraint MS-25 N MS 1S-MS-7C N N N N/A N N N N N N/A Upstream from Restra6nt MS-25 N MS 18-MS-7C MS7C C4A N N N N N/A N N N N N N/A .-

MS 18-MS-7C MS70-C4 upstream side of Main Steam isolation Vane V2-80C

_ , _ _ . . - . . . - - . - - - -- --. . _ . - - - . . . _ - - - . - _ - - -- . - - - ~ . . -- - __. _--. ~ ._ _

Table 4-4 Cont.

. . i, System Une 89dd 99wd TF SCC LC FS D Number Number Loca0 err TASCS TT GSCC TGSCC ECSCC PWSCC BEC PIT CC EC .FAC MS 1MS-7C MS7C C3 Downstream side of Mewt Steam isolaton Vane V2- N N N N N/A N N N N N NA .

80C MS 1WS-7C MSTCC9A Downstream side of Penetration X-7C N N N N NA fJ N N N N N/A MS- 18-MS-7C MS7C C9 Upstream side of V2-86C, N N N N WA N N N N N WA Downstream of Fenetraeon L7C MSD 2-MSD-2C MSD2Cf1 2 BranctiConnectontornV2-80C Y N N N WA N N N N N -N/A MSD .2-MSD-2C MSD2C-F2 Downstream of V2-80C Y N N N NA N N N N N -N/A MSD 2-MSD-2C MSD2Cf3 Doumstream of V2-80C Y N N N N/A N N N N uN ,WA MSD 2-MSD-2C MSD2C-F4 Downstream of V2-80C Y N N N N/A N N N N : N N/A MSD 2-MSD-2C MSD2Cf5 Downstream of V240C Y N N N NA N N N N N N/A MSD 2-MSD-2C MSO2C-F6 Downstream of V2-80C Y N N N NA N N N N N NA MSO 2-MSD-2C MSD2C-F7 Doumstream of V2-80C Y N N N N/A N N N N N N/A MSD 2-MSD-2C MSD2C-F7A Downstream of V2-80C Y N N N N/A N N N N N N/A MSD 2-MSD-2C MSD2Cf7B Downsteam of V2-80C Y N N N WA N N N N N NA MSD 2-MSD-2C MSD2C47C Downstream of V2-80C Y. N N N NA N N- N N N N/A MSD 2-MSD-2C MSD2C-F7D Downstream of V2-80C Y N N N NA N N N N N NA MSD 2-MSD-2C MSD2C-F7E Downstream of V2-80C Y N N N N/A N N N N N N/A MSD 2-MSD-2C MSO2C-F7F Downstream of V2-80C Y N N N N/A N N N N N N/A MSD 2-MSD-2C MSD2C-F8 Downstream of V2-80C Tee Connechan from MSD2C Y N N N WA N N N N N N/A to 3*-MSD-2 MSD 3-MSD-2 MSD2-S4 Downstream of V2-80C and V2-800, Y N N N N/A N N N N N WA At Branch Connedlan to Penetration X4 MSD 3-MSD-2 MSD2-F1 Upsteam side of V2-74 Y N .N N N/A N N N N N N/A MSD 3-MSD-2 MSO2-F2 Downstream side of V2-74 Y N N N lMA N N N N N N/A MSD 3-MSD-2 MSD2-F3 Upsteam side of Penetraton X4 Y N N N WA N N N N N N/A MSD 3-MSD-2 MSD2-F4 Upsteam side of V2-77 Y N N N NA N N N N N N/A Downstream of Penetragon X4 9

i Table 4-5 !

Weld Locations on Main Steam Loop D 4 i System Une 99Wef 19Waf TF SCC LC FS {

JD Number Number Locadon TASCS TT IGSCC TGSCClECSCC POVSCC 80FC PfT CC EC FAC l

) MS 1&MS-7D MS7D-N3D-SW Doumstream side of Reactor Vessel Nozzle N3-D N N N N .N/A N .N N N N N/A I l MS 1tHIS-7D MS7D-08 Downstream of Reactor Vesset Nozzle N3-D N N N N WA N N N N N NA MS 1&MS-7D MS7DO7D doumstream of Reactor Vessel Nozzle N3-D N N N N N/A N N N N N NA MS 18-MS-7D MS7D-D7C Downstream of Reactor Vesset Nozz$e N3-D N N N N N/A N N N N N N/A MS 1&MS-7D MS7D-07B Downstroom of Reactor Vessel Nozzle N3-D N N N N N/A N N N N N NA l MS 18-MS-7D MS7DO7A Downstream side of Reactor Vessel Nozzle N3-D N N N N N/A N N N N N N/A MS ttMIS-7D MS7D07 Upstream from Spring Hangers MS-30 and MS-31 N N N N NA N N N N N .N/A f MS 1&MS-7D MSTD-068 Upstream side of Ebow, N N N N NA N N N N N N/A [

Dow istream of Spring Hangers MS-30 and MS-31 !

j MS 18-MS-7D MS7D-D6A Downstream sede of Ebow, N N N N NA N N N N N N/A f Downstream of Spring Hangers MS-30 and MS- t 31 l

. MS 16-MS-7D MS7D 06 Downstream of Ebow. N N N N N/A N N N N N N/A i Upstream from RV2-71D l MS 18-MS-7D MS7D-05K Upstream from RV2-71D N N N N N/A N N N N N NfA

{

MS 1&MS-7D MS7D-051 ReHet Vatwe RV2-71D N N N N N/A N N N N N WA k

- MS 18-MS-7D MS7D-05J Retof Valve RV2-71D N N N N WA N ,N N N N N/A f MS 18-MS-7D MS7D-05H Retet Valve RV2-710 N N N N WA N N N N N WA r MS 18-MS-7D MS7DOSF Safety Valve SV2-700 N N N N N/A N N N N N N/A [

i MS 18-MS-7D MS7D-05G Safety Vatwe SV2-70D N N- N N WA N N N N N TA [

MS 18-MS-7D MS7D-OW Safety Valve SV2-700 N N N N NA N N N N N N/A MS 18-MS-7D MS7D-D50 Upstream from Spring Hanger MS-34 N N N N N'A N N N N .N N/A g MS 18-MS-7D MS7DOSC Upstream from Spring Hanger MS-34 N N N .

N N/A N N N N N N/A j MS 18-MS-7D MS7D-058 Upstream from Spring Henger MS-34 N N N N N/A N N N N N- N/A l MS 1844S-7D MS7D-DSA Downstream of Spring Hanger MS-34, N N N N MA N = N N N N N/A Upstream from Snubber MS-3s ,

MS 18-MS-7D MS7 DOS Upstream tom Snubber MS 35 .M N N N NA N N .N N N MA i MS 1&MS-7D MSiD-D11 Upstream side of Ebow. N N N N WA f3 M N N N WA

. Downstream of Snubber MS-35 I MS 1&MS-7D MS7DO4 Upstream side of Main Steem isoleton Valve V2- N N N N NA N N N M N jMA f l

000 '

p i MS 1&MS-7D MS7D-03 Downstreem side of Main Steam isolation Vatwe N N N N WA N N 'N ,N 14 WA

, V2-80D !

MS 18-MS-7D MS7D 09A Downstroem side of Penetrabon X-7D N N N (N N/A N N N N N WA f 4 ' _

i' MS 18-MS-7D MS7D-09 Upstream sede of Main Steam isoiston Vatve V2- N N N N NA N N N N N NA (

860 4 MSD 2-MSD-2D MSO2D-F1 2* Brancti Connecton from V2-800 Y N N N N/A N N N N N N/A t MSD 2-MSD-2D MSD2D-F2 Doumstream of V2-80D Y N N N NA N :N N N N N/A I 4

I 6

i

4 - __ 1 . - . _ . . -.~. . . . .. . - _ . -- ~ - . - --. m. - m . .. - - _.- . _. ._-m-=-------~ _ _ _ _ - . . . . _ - - . . _ . . _ .

Table 4-5 Cont.

i

! ~.-

4- Sys8ser Lame 3MedW IMedW TF SCC LC FS l

D Nanenber Nunaber Lacemen TASCS TT JGSCC TGSCC ECSCC MtSCC NC MT CC EC FAC 7 r

MSD - 2-MSD-2D MSD2D-F3 Douunsteem of V2-80C Y- N N N WA N N' N N N WA ..

4 MSD 244SD-2D MSD2D F4 Douunsteem of V2-80D Y N N N MA N N N N N .WA

[

-[

MSD 2-MSD-2D N5 Douunsteem of V2-80D - Y N N N WA N N N N N WA [

MSD 2-MSD-2D MSD2D-F6 Upeteem of Reducer e T MSD-2 Y f1 N N- MA N ,N g N N N NA [

t: MSO 2-MSD-2D MSD2D-F7 Upsteem of Reducer e T MSD-2 Y N N N .

MA N N N N N WA MSD 244SD-2D MSD2D-F8 Upsteem side of Reducer 2 T MSD-2 Y M N N- N/A N N N iN N PtA ,

MSD 3-MSD-2D MSD2-S3 Doesnsteam of V2-80D at Reducer 2 7 MSD-2 Y N N N. MA N N N N N NA 1 >

i i $

l 4

f i

i i

l w

1 9

i i

4 4

I i I j m o + e y P 1.w 'r y - , s ,, y-g., y..e_ , _g w _ , , , , , , , , , , ,

4 a I f

I Table 4-6 Weld Locations on HPCI Steam Supply ;

System Unc . Wedef ItWtf TF SCC LC FS l

IO Number Number Loce6twe TASCS IT IGSCC TGSCC ECSCC PWSCC nNC PfT CC 'EC FAC \

HPCI 10-MS-4A MS4M1 At HPCI Tapoff from Main Steam,inside Drywet N N N N NA N N N N N KA HPCI 10-MS-4A MS4A-F1A Between Main Steam Tapoff and Hanger HPCI-1 N N N N N/A N N N N N NA i inside Dmmet f HPCI 10-MS-4A MS4M1B Between Main Steam Tapn3 and Hanger HPCI-1 N N N N N/A N N N N N ',NA *

i inside Dymes I i I

HPCI 10-MS-4A MS4A-F1C Be* ween Main Steam Tapoff and Hanger HPCl-1 N N N N NA N N N N N N/A I inande Drywee

, HPCI 10-MS-4A MS4A-F2 Between Main Steam Tapoff and Hanger HPCI-1 N N N N NA N :N N N N NA [

inside Drywee ,

~

HPCI 10-MS-4A MS4A-F2A Upstream sede of Ebow. N N N N/A N N '

N N N N/A c I

Upstream of Restraints HPCI-t and HPCI-2 HPCI 10-MS-4A MS4A-F3 Downstream of Elbow. Upstream of Restraents HPC3-1 N N N N N/A N

[N N N N NA HPCI 10-MS-4A MS4A-F3A Downstream of Restrasnts HPCI-1 and HPCl-2 N N N N N/A N -N N N N NA l Upstream from Spring Hanger HPCl-3 l HPCI 10-MS-4A MS4A-F3B Downstream of Restralis HPG8-1 and HPCI-2 N N N N NA N N N N N NA [

Upstream from Spring Hanger HPCI-3 I

[

HPCI 10-MS-4A MS4A-F3C Upstream side of Elbow. N N N N NA N .

N N N N NA Downstream of Spring Hanger HPCI-3 !

HPCI 10-MS-4A MS4M3D Downstream side of Elbow. N N N N N!A N N N N N NA [

q

~

Upstream of Restraint HpC14 i HPCI 10-MS-4A MS4M4 Upstream sede of Manual Vane V23-15 N N N N MA N N N N N N/A !

HPCI 10-MS-4A MS4A-F5 Doumstream side of Manual Vane V23-15 N N N N MA N N N N N N/A

} HPCI 10-MS-4A MS4A-F5A Upstream side of Ebow. N N N N NA N N N N N NA j 0 Downstream of Penetraton X-11 !

l HPCI 10-MS-4A MS4A-F6 Upstream side of Ebow. N N N N N/A N N N N N N/A l Downstream of Penetraton X-11 i

, HPCI 1MtS-4A MS4A-Ftw Downstreamsideof Ebow. N N N N NA N N N N N NA [

Downstream of Penetra6on X-11 HPCI 104tS-4A MS4M6B Upstream side of Elbow. N N N N NA N N N N N NA Upstream of MOV 23-16 HPCI 10-MS-4A MS4M6C Downstream side of Ebow. N N N N N/A N N N N N N'A Upstream of MOV 23-16 j HPCI 10-MS-4A MS4A-F7 Upstream side of MOV 23-16 N N N -N/A N N N .N N/A i lN lN e

r

= {

l i

I l

i . - - _- _ _ _ _ _ _ _ ___ - - _ _ _ _ _ _ __ . . -

1 Table 4-7 Weld Locations on RCIC Steam Supply -

System Une WoM 99def TF SCC LC FS .,

ID Number Nurnber Locaden TASCS TT NESCC TGSCC ECSCC PWSCC ENC PET CC EC FAC RC!C 3-MS-SA MSSA-Ft Downstream of Main Steam Branen Connecton to ROC N N N N NA N N N N N N/A ROC 3-MS-SA MSSA-F1A Upstream seoe of Elbow. N N N N NA N -

N N N N ft/A Downstream of Brane Connec5an RQC 3-MS-5A MS5A-F18 Downstream of Brand Connecton, N N N N NA N N N N N NA Upstream from Restramt RQC4460 ROC 3-MS-CA MS5A-F1C Downstream side of Elbow, N N N N NA N N N N N NA Upstream from Restraint ROC-H60 ROC 3 MS-5A MSSA-F1D . Upstream side of Elbow. N N N N N/A N N N N N N/A Upstream fatim Spring Hanger RQC-1 RCIO 3-MS-5A MS5M1E Downstream sade of Elbow. N N N N NA N N N N N N/A Upstream from Spring Hanger RQC-1 RCIC 3-MS-5A MSSA-F2 Upstream tide of Valve V13-15 N N N N N/A N N N N N NA RCIC 3-MS-5A MSSA-F3 DJwnSiream sede of Vafve V13-15 N N N N N/A N N N N N N/A RCIC 3-MS-SA MS5A-F3A Downstream of Vatve V13-15 N N N N *WA .N N :N N N TA RCIC 3-MS-5A MS5A-F3B Downstream of Vafve V13-15 N N N N NA N N N N N N/A ROC 3-MS-5A MSSA-F4 Upstream of Penetradon X-10 N N N N N/A N N N N oN N/A Downstream from Spring Hanger RCIC-2 RCIC M S-5A MS5A-F4A Downstream side of Penetraton X-10, N N N N NA N N N N N N/A Upsteam from varve Vt3-16 RQC 3-MS-5A MSSA-F5 Downstream of Penetraton X-10, N N N N NA N N N N N N/A Upstream from Vafve V13-16 RCIC 3-MS-5A MSSA-FSA Doomstream of Pee X-10 N N N N N/A N N N N N NA Upstream from Valve V13-16 RCIC 3-MS-5A MSSA-F5B Downstream of Penetraton X-10 N N N N N/A N N N N N N/A RCIC 3-MS-SA MSSA-FSC Downstnum of Penetraton X-10 N N N N N/A N N N N N N/A RCIC 3-MS-5A MSSA-FS Dowratream of Penetraton X-10 N N N N NA N N N N N N/A MS-5A Ups! ream side of Valve V13-16 N N N N NA N N N N N NA ROC MSSA-F7

o 5.0 MAIN FEEDWATER 5.1 Main Foodwater System Description The Main feedwater system is the source of cooling water for the reactor.

5,2 Main Feedwater System Class 1 Boundary The Class 1 portion of the main feedwater system starts at the reactor vessel nozzles, N-4A, N-4B, N 40 and N-4D [3].

Nozzle N-4A is connected to Line 10-FDW-10. Nozzle N-4B is connected to Line 10-FDW 21.

Lines 10-FDW-19 and 10-FDW-21 join together to feed into Line 16-FDW-19 which is connected to Line 16-FDW-16 (Feedwater Line A). The Class 1 portion of Feedwater Line A -

(Line 16-FDW-16) ends at Valve V2-27A [3,13,14] (HPCI piping is attached to Feedwater Line A).

l Nozzle N-4C is connected to line 10-FDW-18. Nozzle N-4D is connected to line 10-FDW-20.

1 Lines 10-FDW-18 and 10-FDW-20 Join together to feed into Line 16-FDW-18 which is connected to 16-FDW-17. (Feedwater Line B). The Class 1 portion of Feedwater Line B (Line 16-FDW-17) ends at Check Valve FDW-96A [3,13,14]. (RCIC piping is attached to Feedwater Line B)

Tcble 5-1 lists the Class i lines within the main feedwater system and defines their operating cnd design conditions [4,5].

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 35 of 73

' j

4 4 Table 61 Main Feedwater Class 1 Lt.7es and Operating / Design Conditions Line Pipe Pipe Pipe Des 6gn Design Op. Notes Number Diameter Thickness Material Pressure Temp. Temp.

[3,4, 5] [3,5.13,14] [4] [4] [4] [5]

10-FDW- 10" (1) Sch.80 CS-5* 1250 psig 575* 304' 1) Per Ref. 3 (Loop 19 A) 10-FDW. 10" (1) Sch.80 CS5* 1250 poig 575' 304' 1) * (Loop B) 21 10-FDW- 10" (1) Sch.80 CS-5* 12b0 psig 575' 304" 1) * (Loop C) 18 10-FDW- 10" (1) Sch.80 CS 5* 1250 psig 575' 304' 1) * (Loop D) 20 16-FDW. 16" Sch.120 CS-5* 1900 psig 400* 304' (Loops A and B) 16 16-FDW- 16" (2) Sch.80 CS 5' 1900 psig 400' 304' 2) Per Ref. 3 18 (Loops C and D) 16-FDW- 16" (2) Sch.120 CS 5* 1900 psig 400* LO4' 2)*

17 16-FDW- 16" (2) Sch.80 CS-5' 1900 psig 400* 304' 2)*

19(4) 0 Piping systems (24 inch nominal diameter and less) with a pipe codo CS-5 and classification of Paragraph 1.1, are fabricated from carbon steel por ASTM A 106, Grade B [4).

5.3 Main Feedwater System Wold Locations Class 1 B-J weld locations for Main Feedwater Lines A and B are included as Table 5-2 and Table 5-3 [7,13,14).

5.4 Main Feedwater System Degradation Mechanisms Evaluation The evaluation of the degradation mechanisms per the criteria in Table 2-2 for the main feedwater system is presented in Appendix C. Highlights of this evaluation are provided below for all the mechallums.

Revision: 8/6/97 Prepared lly/Date:

Checked Ily/U:te:

1 File No. EPRI-116-301 Page 36 of 73

5,4.1 Thermal Fatigue (TF) 5.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS)

The horizontal segment of Feedwater Line B downstream of the Class 1-to-Class 2 boundary (up to Weld FW17-F6) are affected by the TASCS Degradation Mechanism due to the potential for RWCU flow via the RCIC connection during plant startup/ shutdown.

5.4.1.2 Thermal Transients (TT)

Both Feedwater Line A and Line B are affected by TT in close proximity to the reactor vessel (horizontal sections of Lines 10-FDW-19, Line 10-FDW 21, Lines 10-FDW-18, and Line 10-FDW-20 to first elbow) due to hot reactor water backflow into cold FW piping.

5,4.2 Stress Corrosion Cracking (SCC) 5.4.2.1 Intergranular Stress Corrosion Cracking (IGSCC)

The Main Feedwater System is not affected by the IGSCC Degradation Mechanism due to the

, f;ct that the piping is composed of carbon steel (A-106, Grade B)[4], a material that is not susceptible to IGSCC.

5.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC) l The Main Feedwater System is not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, por VY's implementation of the EPRI Water Chemistry Guldelines [34).

5.4. 2.3 Extemal Chloride Stress Corrosion Cracking (ECSCC)

The ECSCC Degradation Mechanism is not applicable to the Main Feedwater System due to the fact that the system is composed of carbon steel (A-106, Grade B)(4).

5.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The Main Feedwater System is not affected by the PWSCC Degradation Mechanism due to the fact that this plant does not experience temperature conditions greater than 620*F and this system does not contain any Inconel.

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 37 of 73

. 1

e e 5.4.3 Localized Corrosion (LC) 5.4.3.1 Microbiologically Influenced Conosion (MIC)

The Main Feedwater System is not affected by the MIC Degradation Mechanism due to the j fCct that this system is exposed to an operating temperature greater than 150'F [5]. j l'

5.4.3. 2 Pitting (PIT)

The Main Feedwater System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines [34).

5.4.3.3 Crevice Corrosion (CC)

The Main Feedwater System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the thermal sleeves in the vessel nozzles are not part of the in-

, scope piping.

5.4.4 Flow Sensitive (FS) 5.4.4.1 Emslan-Cavitation (E-C)

The Maln Feedwater System is not affected by the EC Degradation Mechanism due to the fact that the operating temperature is greater than 250'F [5).

5.4.4.2 Flow Accelemted Corrosion (FAC)

The Main Feedwater System is a part of VY's FAC program [37]. As discussed in Section 1.3, program results have indicated that nine locations are susceptible to FAC. (It should also be noted that these locations are being routinely inspected as part of the implementation of this program.) For purposes of this evaluation, these nine locations are also considered susceptible to FAC.

5.4.5 Water Hammer From Reference 36, the main feedwater system is not affected by the Water Hammer Degradation Mechanism.

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 38 of._.23L

Table 5-2 Weld Locations on Main Feedwater Line A System Une Wekt 89Mtf TF SCC LC FS '~ s 10 Number Number Lacedon TASCS TT IGSCC TGSCC ECSCC PWSCC RNC PfT CC EC FAC FW 1MDW-19 FW19-N4A-SW Downstream sWe of Reador Vessel E-4A N Y N N N/A N N N N N MA , ,

FW- 10fDW-19 FW1M7 Upstream side of Reador Vessel E-4A N Y N N N/A N N N N N .N/A FW 10fDW-19 FW19-F6A Downstreamof Etow. N Y N N N/A N N N N N N/A Opsteam of Reactor Vessel Nozzle E 4A FW 10 FDW-19 FW19-F6A-SA Downstream side of Elbow. N Y N N N/A N N N N N NA Upstream of Reador Vessel Nozzle E-4A FW 10-FDW-19 FW1M6A SB Upstream side of Ebow, N Y. N N WA N N N N N WA Downstream of Spring Hangers F1 and F2 FW 10-FDW-19 FW1M6 Upstream of Spring Hangers F1 and F2 .N N N .N WA N N N N N N/A FW 10fDW-19 FW1M6-SA Upsiream of Sprirtg Hangers F1 and F2 N N N N ,N/A N .N N N fe N/A FW 1MDW-19 FW1MSA D.wmstream side of Elbow. N N N N N/A N N N N N N/A Downstream of Snubber FW-3 FW 10-FDW-19 FW1945 Upstream sede of Ebow, N N N N MA N N N N N MA Downstream of Snubber FW-3 FW 1MDW-19 FW19f4A Downstream of Restraent FW-5. N N N N N/A N N N N N N/A Upstream of Spring Hanger FW 4 FW 10-FDW-19 FW1M4 Downstream sh3e of Reducer, N N N N N/A N N N N N Y Downstream of Spring Hanger FW-9 FW 1MDW-21 FW21-N48-SW Downstream side of Reactor Vessel Nozzle N-4B N Y N N N/A N N N N N N/A FW 1MDW-21 FW21-F3 Upstream side of Reactor Vessel Nozzle N-4B N Y N N N/A N N N N N N/A FW 10-FDW-21 FW21f2A Upstream of Reactor Vessel Nozzle N-48 N Y N N WA N N N N N ,N/A FW 10fDW-21 FW2142A-SA Downstream of Spring Hangers FW-7 and FW-8, N Y N N N/A N N N N N N/A Upstream from Reactor Vessel Nozzle N-48 FW 1MDW-21 FW2142A-SB Upstream of Spring Hangers FW-7 and FW-8 N Y N N N/A N N .N N N N/A FW 10fDW-21 FW21-F2 Downstream ot Brandt. N N N N NA N N N N N NA Upstream from Spring Hangers FW-7 and FW-8 FW 10fDW-21 FW2142-SA Downstream of Brandt. N N N N N/A N N N N N N/A Upstream from Spring Hangers FW-7 and FW-8 FW 1MDW-21 FW2141. Downstream of Brancti Connechon w/10" FWD-19 N N N N N/A N N N N N Y FW 16-FDW-19 FW19f3C Upstream side of Reducer, N N N N N/A N N N N N Y Downstream of Spring Hanger FW-9 FW 16-FDW-19 FW1M3B Downstream of Spring Hanger FW-9, N N N N WA N N A N N Y Upstream from Reducer Downstream of Spring * .*.qper FW-9, N N N N N/A N N N N N N/A FW 1SfDW-19 FW19f3A Upstroom from Reducer N N N N N/A N N N N N N/A FW 16fDW-19 FW19f3 Downstream of Spring Henger FW-9, Upstroom from Redumr Doumstream of Ebow, N N N N N/A N N N N N N/A FW 16fDW-19 FW1942D Upstroom of Spring Hanger FW-9 FW19f2C Downstream side of Elbow, N N N N N/A N N N N N N/A FW 16-FDW-19 Downstream of Restraint FW-10 N N N N N/A N N N N N N/A FW 16fDW-19 FW19-F28 Downstreem of Restraint FW-10 Upstroom of Ebow

frekf TF SCC LC FS System Une IWedW Nwnber Number Locason TASCS TT sSCC [TGSCC ECSCClPWSCC ANC lMT CC EC so lFAC Downstream W Manual Vane V2-29A, N N N N N/A N N N N N NrA

)- FW 16-FDW-19 FW19-F2A W_ _.. d Elbow Downstream side d Manual Vane V2-2M N N N N ,NA N ,N N N N N/A

- FW 1MDW-19 FW19-F2 Upstream Sede d Manual Va% V2-29A N N N N NA N N N N N N/A FW 16-FDW-16 FW16f10 ;

FW16-F9A . Restraint FW11 and FW22 Weld ??? N N N N N/A N N N N .N N/A FW 16-FDW-16 FW 16-FDW-16 FW16-F9 Downstream side d CheckVaNe V2-28A N N N N NA N N N N N .N/A 16-FDW-16 FW16-F8A Upstream sede d Check Vane V2-28A N N N N N/A N N N N N N/A FW FW16-F8 Upstream Sede d Penetratran X-M, N N N N N/A N N N N N N/A FW 16-FDW-16 Downstsam W Check Vane V2-27A FW 16-FDW-16 FW16-MF7 Downsseam Side d Check Vane V2-27A N N N N NfA N N N N N N/A 1

i i

1 i

i i

i a 0

.~+

.=

s

.. -- -. . _ - - _ _ _ - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ ~ _ _ . _ _ _ - . _ _ .

__. ___ _ _ ___ __ __ - - _ - - - _ - - - - _ . _ _ . - . - - - - . . - - . --_ _ -_ _.- m_ _ _-

i i

Table 5-3

. Weld Locations for Main Feedwater Line B ..I .

System Une 9Vekt 99%f TF SCC LC FS

~*

10 Number Number Locathm TASCS TT N3 SCC TGSCC ECSCC P9FSCC BNC PfT CC EC FAC .

FW 10-FDW-18 FW18-N4C-SW Doumstream side of Reador Vessel Nozzle N-4C N Y N N N/A N :N N N N N/A FW 1MDW-18 FW18-F6 Upstream side of Reador Vessed Nozzle N-4C N Y N N N/A N N N N .N NA FW 1MDW-18 FW16 FSA Doomstreamof Ebow. N Y N N N/A N N N N N N/A !

4 Upstream of Reador Vessel Nozzle N-4C FW 10-FDW-18 FW18-F5A-SA Downstream side of Elbow. N Y N N N/A N N N N N N/A I Upstream from Reador Vessc4 Nozzle N-4C [

FW 10-FDW-18 FW18 F5A-SB Upstream side of Ebow, N Y N N N/A N N N N N N/A

- Downstream of Spring Hangers FW-18 and FW-19 l

. FW 1MDW-18 FW18-F5 Upstream of Spring Hangers FW-18 and FW-39 N N N N N/A N N N N N N/A }

FW 10-FDW-18 FW1MMA Downstream of Branch N N N N N/A N N N N N N/A a

i FW 1MDW-18 FW18-F4 Downstream of Branch Connechon with 10" FWD-20 N N N N N/A N N N N N Y ;

i i FW 10-FDW-20 FW2p4D-SW Downstream side of Reador Vessel Nozzle N-4D N Y N N N/A N .N N N N N/A i i FW 1MDW-20 FW20-F4 Upstream side of Reador Vessel Nozzle N-4D N Y N N N/A N :N N N N N/A .(

FW 10-FDW-20 FW2M3A Downstream of Ebow. N Y N N N/A N N N N N N/A Upstream of Reador Vessel Nozzle N-40 j FW 10-FDW-20 FW20-F3A-SA Downstream side of Etow. N Y N N N/A N N N N N N/A i Downstream of Spring Hangers FW-12 and FW-13 FW 10-FDW-20 FWM3MB Upstream side of Etow, N Y N N N/A N N N N N N/A !

Downstream of Spring Hangers FW-12 and FW-13 .

] FW 1MDW-20 FW20 F3 Upstream of Spring Hangers FW-12 and FW-13 N N N N N/A N N N N N N/A [

]

FW 1MDW-20 FW2M3SA Upstream of Spring Hangers FW-12 and FW-13 N N N N N/A N N N N N N/A 4 FW 1MDW-20 FW2GF2A Downstream side of Etow, N N N N N/A N N N N N. N/A .

! Upstream of Spring Hangers FW-12 and FW-13

FW 1MDW-20 FW2M2 Upstream side of Ebow, N N N N N/A N N N N N N/A Downstream of Spring Hanger FW-14 FW 10-FDW-20 FW20-F1A Downstreamof Reducer. N N N N N/A N N N N N N/A Upstream of Snubber FW-15 ;

FW 10-FDW-20 cW20-F1B Downstream of Restraint FW-16, N N N N N/A N N N N N Y l

', Upstream of Spring Hanger FW-17 I i FW 10-FDW-20 FW20-F1 Downstream side of Reducer, N N N N N/A N N N N N Y i Downstream of Branch Connecten with 10* FWD l FW 10-FDW-20 FW2M3B Upstream side of Reducer, N N N N N/A N N N N N Y t Downstream of B anch Connodion with 10* FWD-18 I

];

FW 16-FDW-18 FW18-F3A Downstroom of Spring Hanger FW-20, N N N N N/A N N N N N Y l i

j Upstream of Branch FW 16-FDW-18 FW18-F3 Downstream side of elbow. N N N N N/A N N N N N N/A !

1 Upstream of Spring Hanger FW-20 i FW 16-FDW-18 FW18-F2E Upstreamsideof E: bow. N N N N N/A N N N N N N/A l Upsteam of Spring Hanger FW-20 FW 16-FDW-18 FW18-F2D Downstroom side of Emow. N N N N N/A N N N N N N/A Downstream of ManualVaNe V2-29B '

i I

. . -. . _ .. = . . . ...

Table 5-3 Cont .

Syssuun fJne stWef DMuhr TF SCC LC FS JD PJmber Nunnber Lecesen TASCS TT NESCC TGSCC ECSCC POVSCC anC PIT CC EC FAC FW 13-FDW-16 FW16-F2C - Doumstream of Restrart FW-21 N N N N NA N N N N- N NA Upstroom of Elbour FW 16-FDW-16 FW18-F2B Dovmotream of Restract FW-21 N N N N MA N N N N N NA FW 16-FDW-18 FW1tLF2A Doumstream of Manual Valve V2-298 N N N N NA N N N N N NA Upstreem of Restraint FW-21 FW 16-FDW-18 FW1tLF2 Dovmstream side of Manual Vahre V2-298 N N N N NA N N N N N N/A EW 16fDW-17 FW17-F7 Upstream side of Manual Valve V2-29B N N N N WA N N N N N NA FW 16f9W-17 FW17-F6 Doomstream sxte of CheKA Valve V2-288 Y N N N N/A N- N N N N N/A FW 16-FDW-17 FW17-F5A Upstream skic of Check Valve V2-288 Y N N N N/A N N N N N N/A FW 16-FDW-17 FW17-MF4A Upstream skle of Penetraton X-98 (FDW-MD38) Y N N N NA N N N N N N/A FW 16-FDW-17 FW17-MF4 Doomstream sede of Check Valve FDW-96A Y N N N N/A N N N N N N/A 4

9 e

m- - ~ . _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ . _ _ . _ _ _ _ _ _ _ _ _ _ _ . _ . . _ _ _ . . _ _ _ _ _ . _ _ _ . _ _ _ _ _ _ . . _ . . . _ . _ _ _

~

6.0 RESIDUAL HEAT REMOVAL (RHR) 6.1 RHR System Description The residual heat removal (RHR) system consists of two closed loops, each loop containing two parallel pumps, one heat exchanger and the necessary valves and instrumentation. The RHR system is designed to remove decay heat from the reactor under both operational and cccident conditions. [15]

6.2 RUR System Class 1 Boundary The RHR system branches off from the reactor recirculation system (28-PLR). Line 20-RHR-i 32, branches off from the 28-PLR and is the suction line. Lines 24-RHR-30 and 24-RHR-31 feed into 28-PLR and are the discharge lines. [6,27]

Line 20-RHR-32 (which feeds into 28-PLR)is connected to Line 20-RHR-33. All of line 20-RHR-32 and 20-RHR-33 are Class 1. Line 20-RHR-33 starts at approximately Penetration X-12 and ends at Valve MOV 10-17 (suction). [6,16,27]

Line 24-RHR-30 (which feeds into 28-PLR)is connected to Line 24-RHR-28. All of Lines 24-RHR-28 and 24-RHR-30 are Class 1; line 24-RHR-28 starts at Valve V10-46A and ends at Vcive MOV 10-27A (discharge). [6,18,27]

3 Line 24-RHR-31 (which feeds into 28-PLR)is connected to Line 24-RHR-29. All of Lines 24-RHR-29 and 24-RHR-31 are Class 1; Line 24-RHR-29 starts at Valve MOV 10-46B and ends ct Valys V10-27B (discharge). [6,17, 27]

Tcble 6-1 lists the Class 1 lines within the RHR system and defines their operating and design conditions (4,5].

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File No. EPRI-116-301 Page 43 of 73

Table 6-1 RHR System Class 1 Lines and Operating / Design Conditions Line Pipe Slze Pipe Pipe Design Design Op. Notes Number [4, 5, 27] Thickness Material Pressure Temp. Temp.

[27] [4,27] [4,27 [4] [5]

20-RHR- 20" 1.095" min SS-6' 1250 psig 575' 281* (1) Per Ref. 25 32 (1) TP316L (1a) 20-RHR- 20' Sch.80 CS 5' 1250 psig 575' 281' (2) Per Ref. 25 33 (2) 24-RHR- 24" Line List SS-6* 1250 psig 575' 262' 30 24-RHR- 24" Sch.80 CS-5* 1250 psig 575* 262' 20 24-RHR- 24" 1.312" SS-6* 1250 psig 575* 262*

31 min.

24-RHR- 24' Line List CS5* 1250 psig 575' 262' 29

Welded piping systems (greater than 12 inches in diameter) with a pipe code SS-6 (1500 lb stainless steel) are f:bricated from stainless steel per ASTM A 358 Class 1 Grade TP304 or TP316.

- Welded piping systems (greater than 24 inches in diameter) with a pipe code CS 5 (900 lb. carbon steel) and classification of Paragraph 1.1, are fabricated from carbon steel per ASTM A 155, Grade KC-65, Class 1 Firebox Quality [4).

6.3 RHR System Weld Locations Class 1 B-J weld locations for the residual heat removal system (both discharge lines and the one suction line) are included as Tables 6-2 through 6-4 [6,7,16,17,18].

G.4 RHR System Degradation Mechanisms Evaluation Th aluation of the degradation mechanisms per the criteria in Table 2-2 for the RHR sysu,m is presented in Appendix D. Each line (24-RHR-31,24-RHR-30 and 20-RHR-32)is cvaluated separately due to the varying transient conditions existing in these lines. Highlights of this evaluation are provided below for all the mechanisms (and lines).

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6.4.1 ThermalFatigue (TF) 6.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS)

Part of line 20-RHR-32 up to Valve V10-18 in the RHR System (suction) is susceptible to the TASCS Degradation Mechanism due to convection heating.

All of 24-RHR-30 and past Valve V10-46A up to weld (RH-28-15) of line 24-RHR-28 (discharge) are susceptible to the TASCS Degradation Mechanism due to convection heating from the RPV.

Part of line 24-RHR-31 up to Valve V10-81B (Discharge) is susceptible to the TASCS

, Degradation Mechanism due to convection heating.

l 6.4.1.2 Thermal Transients (TT)

Line 20-RHR-32 (suction) upstream of Valve MOV-18 is unaffected by the TT Degradation -

I Mechanism due to the fact that this piping is horizontal and would be preheated by convection h:ating. Line 20-RHR-33 (suction) is affected by the Thermal Transient (TF) Degradation Mechanism due to the fact that hot water is injected into this normally cold piping during shutdown cooling initiation, resulting in a AT greater than 150*F.

l l Lines 24-RHP.-30 and 24-RHR-31 (discharge) are affected by the Thermal Transient (TT)

Degradation Mechanism due to the fact that these lines experience a " double-shock" of hot cnd then cold water injected into cold / hot piping line during shutdown cooling, resulting in a AT greater than 200*F. In addition, Lines 24-RHR-28 and 24-RHR-29 experience hot water injections into normally cold lines dudng shutdown cooling.

It should be noted that additional evaluations could be performed to show that although Lines 24-RHR-28 and 24-RHR-29 are subjected to severe thermal transient during shutdown cooling, the ATew, is greater than the AT that these lines actually experience.

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t l 6.4.2 Stress Corrosion Cracking (SCC) l 6 4.2.1 Intergranular Stress Corrosion Cracking (IGSCC)

Lines 20-RHR-32 (suction), Lines 24-RHR-30 and 24-RHR-31 (discharge) of the RHR System cre not affected by the IGSCC Degradation Mechanism due to the fact that all welds in these lines are classified as lGSCC Category .A per Reference 25 Lines 20-RHR-33 (suction),24-RHR-28 and 24-RHR-29 (discharge) are composed of carbon steel (A-155, Grade KC-65), a material that is not susceptible to IGSCC.

6.4.2.2 Tmnsgranular Stress Corrosion Cracking (TGSCC)

The RHR System is not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34).

6.4.2.3 Extemal Chloride Simss Corrosion Cracking (ECSCC)

Lines 20-RHR-32 (suction), Lint',24-RHR-30 and 24-RHR-31 (discharge) of the RHR System cre not affected by the ECSCC Degradation Mechanism due to the fact that the system is insulated with non-metallic insulation per Reg Guide 1.36 [5). Because Lines 20-RHR-33 (suction),24-RHR-28 and 24-RHR-29 (discharge) are composed of carbon steel (A-155, Grade C) the ECSCC Degradation Mechanism is not applicable.

6.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The RHR System is not affected by the PWSCC Degradation Mechanism due to the fact that this plant does not experience temperature conditions greater than 620*F and this system does not contain any inconel.

6.4.3 Localized Corrosion (LC) 6.4.3.1 Microbiologically Influenced Co.70sion (MIC)

The RHR System is not affected by the MIC Degradation Mechanism due to the fact that this system is exposed to an operating temperature greater than 150*F [5).

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6.4.3.2 Pitting (PIT)

The RHR System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines [34]

6.4.3.3 Crevice Corrosion (CC)

The RHR System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. Because this system is connected to the recirculation system at 28-PLR and does not contain any nozzles, no crevice conditions exist for this mechanism to be active.

6.4.4 Flow Sensitive (FS) 6.4.4.1 Erosion-Cavitation (E-C)

The RHR System is not affected by the EC Degradation Mechanism due to the fact that the operating temperature is greater than 250*F [5].

6.4.4.2 Flow Accelerated Corrosion (FAC) i l

Because Lines 20-RHR-32 (suction), Lines 24-RHR-30 and 24-RHR-31 (discharge) of the RHR System are composed of stainless steel (TP316L), they were excluded from Reference 37, assuming that they are resistant to FAC due to its high chromium content (>5%). Thus, they are not affected by the FAC Degradation Mechanism. Although Lines 20-RHR-33 (suction),24-RHR-28 and 24-RHR-29 (discharge) are composed of carbon steel (A-155, l

Grade KC-65), they were not included in Reference 37.

6.4.5 Water Hammer From Reference 36, the RHR (suction and discharge lines) system is not affected by the Water Hammer Degradation Mechanism.

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File No. EPRI-116-301 Page 47 of 73 .

i

l Tcble 6-2

~ Weid Locations for Residual Heat Removal System (Line 20-RHR Suction) nwd 19%t TF SCC. LC FS System Une Number Lacetion TASCS 1T N3 SCC TGSCC ECSCC PWSCC nlFC PIT CC EC FAC.

W Number Y N N N N N N N N N N/A RHR 20-RHR-32 RH-32-1 Downsteem of Brane Connecnon from 28 PLR to 20" RHR-32 RHR 20-RHR-32 RH-32-2 Downstream of Bran @ Conneceon fron. 28" PLR to 20" RHR-32 Y N N N N. N N N N N NA M _.. side of Ebow Y N N N N N N N N N N/A RHR 20-RHR-32 RH-32-3 Downstream of Brane Connecton from 28* PLR to 20" RHR-32 Downstroom side of Ebow Downstroom of Brand Connecean to RWCU line 4* CUW-18 Y N N N N N N N N N N/A RHR 20-RHR-32 RH-32-4 Upstream side of Valve V10-88, Y N N N N N N N N N NA-RHR 20-RHR-32 RM-32-5 Downstream of Brand Connection to RWCU line 4* CUW-18 Downstream side of Valve V10 88, Y N N N N N N N N N N/A ,

RHR 20-RHR-32 RH-32 6 Upstroom of Vaive V10-18 Upstroom side of Valve V10-18, Y N N N N N N N N N N/A RHR 20-RHR-32 R&32-7 Upstream of Snubber RHR-3 Downstroom side of Valve V10-18, N Y N N N N N N N N N/A RHR 20-RHR-32 RH-32-8 M ..of Snubber RHR-3 N N N N NA Downstroom of Valve V10-18, N- Y N N N N RHR 20-RHR-32 RM-32-9 Mei.of Etow N N N N N N N N N/A RHR 20-RHR-32 RH-32-10 Upstream side ciEmow, N Y Downstream from Valve V10-18 N Y N N N N N N N N NA RHR 20-RHR-32 RH-32-11 Downstroom of Elbow, Downetream from Snubber RHR4 N Y N N N N N N N N N/A RHR 20-RHR-32 RH-32-12 Upstream side of Etow, M _r. from Penetration X-12 N/A N Y N N N N N N N N RHR 20-RHR-32 RH-32-13 Lownstream side of Etow, tg_ii from Penetracon X-12 N Y N N N N N. N- N N N/A RHR 20-RHR-32 RH-32-14 Downstroom of Ebow, (M, T.from Penetrallon X-12 N- Y N N N/A N N N N N N/A -

RHR 20-RHR-33 RH33-15 Downstroom of Penetra60n X-12 N Y N N NA N N N N N N/A RHR 20-RHR-33 RH33-18 Downstroom of Penetraton X-12 Downstream of Penetration X-12, N. Y N N N/A N f[ N N N N/A RHR 20-RHR-33 RH33-17

@ _ c. from MOV 10-17 Downstroom of Penetrs50n X-12, N Y N N N/A N N N- N N N/A RHR 20-RHR-33 RH33-18 M _.. from MOV 10-17 N N N N N/A Upstream side of MOV 10-17 N Y N N N/A N RHR 20-RHR-33 RH33-19

~

O

1 l

Table 6-3 i Weld Locations for Residual Heat Removal System (Line 24-RHR Discharge) *l System Line Weld Weld TF SCC LC FS .,j ID Number , Number Location TASCS TT IGSCC TGSCC ECSCC PWSCC nflC PIT CC EC FAC RHR 24-RHR-30 RH-30-1 Upstream of Branch Connecbon 28-PLR to 24* RHR-30 Y Y N N N N N N N N N/A

'q RHR 24-RHR40 RH-30-2 Downstream side of Elbow, Y Y N N N N N N N N N/A l Downstream of Branch Connection 28-PLR to 24* RHR-30 l RHR 24-RHR-30 RH-30-3 Upstream side of Elbow, Y Y N N N N N N N N N/A Downstream of Branch Connecuon 28-PUt to 24* RHR-30 RHR 24-RHR-30 RH-30-4 Downstream side of Vahre V10-81A Y Y N N N N N N N N N/A RHR 24-RHR-30 RH-30-5 Upstream side of Vafve V10-81A Y Y N' N N N N N N N N/A RHR 24-RHR-30 RH-30-9 Upstream side of Elbow, Y Y N N N N N N N N N/A Upstream of Valve V10-81A RHR 24-RHR-30 RH-30-6 Upstream side of Elbow. Y Y N

N fi N N N N N/A Upstream of Vafve V10-81A RHR 24-RHR-30 RH-30-7 Downstream of Check Valve V10-46A Y Y N N N N N N N N N/A RHR 24-RHR-30 RH-30-8 Downstream side of Check Vahre V10-46A Y Y N N N N N N N N N/A RHR 24-RHR-28 RH-28-12 Upstream side of Check Vatve V1046A Y Y N N N/A N N N N N N/A RHR 24-RHR-28 RH-28-14 Upstream side of Check Vafve V10 46A, Y Y N N N/A N N N N N N/A Upstream of Spring Hanger RHR-8 RHR 24-RHR-28 RH-28-15 Downstream side of Elbow. Y Y N N N/A N N N N N N/A Upstream from Check Valve V10-46A RHR 24-RHR-28 RH-28-16 Upstream side of Elbow, N Y ,N N N/A N N N N N N/A Upstream from Check Vatve V10-46A RHR 24-RHR-28 RH-28-17 Downstream skle of Elbow, N Y N N N/A N N N N N N/A Downstream from Drywell Penetration X-13B 4

RHR 24-RHR-28 RH-28-18 Upstream side of Elbow, N Y N N N/A N N N N N N/A Downstream from Drywell Penetration X-138 RHR 24-RHR-28 RH-28-19 Downstream side of Drywen Penetration X-138 N Y N N N/A N N N N N N/A RHR 24-RHR-28 RH-28-20 Upstream of Drywell Penetrabon X-138 N Y N N N/A N N N r4 N N/A 24-RNR-28 RH-28-21 Downstream side of Elbow, N Y N N N/A N N N N N N/A RHR Upstream of Drywell Penetration X-13B RHR 24-RHR-28 RH-28-22 Downstream side of MOV 10-25A :4 Y N N N/A N N N N N N/A RH-28-23 Upstream side of MOV 10-25A N Y N N N/A N N N N N N/A RHR 24-RHR-28 RH-28-24 Upstream side of Elbow, N Y N N N/A N N N N N N/A RHR 24-RHR-28 Downstream from MOV 10-27A Downstream side of MOV 10-27A N Y. N N N/A N N N N N/A RHR 24-RHR-28 RH-28-25 g,4 L___ c-e

Table 6-4 _

Weld Locations for Residual Heat Removal System (Line 24-RHR Discharge) l l

TF SCC LC- FS System Une Weht Wekt TASCS TT IGSCC TGSCC ECSCC PWSCC M9C PIT CC EC FAC ID Number Number LoceNon Y N N N N N N N N N/A RHR 24-RHR-31 RH-31-1. Upstream of Branm Conneceon from 28* PLR to 24* RHR-31 Y '

Y Y N N N N. N N N N N/A RHR 24-RHR-31 RH-31-2 Downstream side of Elbow.

l Upstream of Branch Connechon from 28* PLR to 24" RHR-31 Y Y N N. N N N N N N N/A RHR 24-RHR-31 RH-31-3 Upstream sloe of Elbow,

@esm of Branch ConnecBon from 28" PLR to 24* RHR-31 N N N/A Y Y N N N N N N RHR 24-RHR-31 RH-31-4 Downstream side of Valve V10-818 N Y N N N N N N N N N/A RHR 24-RHR-31 RH-31-6 Upstream side of Valve V10-818 N Y N N N N N N N -N N/A RHR 24-RHR-31 RH-31-7 Downstream side of Check Vafve V10-46B N Y N N N/A N N N N N N/A RHR 24-RHR-29 RH29-10 Upstream side of Check Valve V1046B N Y N N N/A N N N N N N/A RHR 24-RHR-29 RH29-11 Upstream side of Elbow.

Upstream from Check Vafve V10-468 N Y N N N/A N N N N N N/A RHR 24-RHR-29 RH29-12 Upstream of Spring Hanger RHR4, Downstream from Drywell Penetration X-13A N Y N N *l/A N N N N N N/A RHR 24-RHR-29 RH29-13 Downstream side of Drywen Penetration X-13A N Y N N N/A N N N N N N/A RHR 24-RHR-29 RH29-14 Upstream side of DryweR Penetration X-13A N Y N N N/A N N N N N N/A RHR 24-RHR-29 RH29-15 Downstream of MOV 10-250 N Y N N N/A N N N N N N/A -

RHR 24-RNR-29 RH29-16 Downstream side of MOV 10-258 -

N Y N N N/A N N- N N N N/A RHR 24-RHR-29 RH29-17 Upstream side of MOV 10-25B N Y N N N/A N N N N N- N/A RHR 24-RHR-29 RH29-18 Downstream of MOV 10-278 N Y N N N/A N- N N N N N/A RHR 24-RHR-29 RH29-19 Downstream of MOV 10-27B e

e O e

- +

aw

f 7.0 CORE SPRAY SYSTEM 7.1 CS System Description The core spray system (CS) provides cooling of the core to prevent fuel clad melting in the cvent of a coolant loss sufficient to uncover the core. Two independent loops are provided, c ch consisting of one 100% capacity centrifugal pump, a spray sparger in the reactor vessel cbove the core, piping and valves to convey water and the associated controls and instrumentation. If high pressure in the drywell or low-low water level in the reactor vessel with reactor vessel pressure below 350 psig occurs, the CS system will automatically spray water onto the top of the fuel assemblies to prevent fuel clad melting. [19]

7.2 CS System Class 1 Boundary The Class 1 portion of the CS starts at the reactor vessel nozzles (N-5A and N-58) which are connected to Lines 8-CS-4A and 8-CS-48. These lines end at Valves MOV CS-12A and MOV CS-128. [3. 20, 21, 29]

Tcble 7-1 lists the Class 1 lines within the CS system and defines their operating and design conditions (4,5].

Table 7-1 CS System Class 1 Lines and Operating / Design Conditions

^

Line Pipe Size Pipe Pipe Design Design Op. Notes Number [4, 5,29] Thickness Material Pressure Temp. Temp.

- [4, 29] [4, 5, 20) [4] [4] [5]

8-CS-4A 8' Sch.100 SS-6* 1250 psig 575* 550' (1) Per. Ref. 29, pipe Type mat 1 from RPV to V-316L (1) 23-14N14B is SA312, Type 316L.

Remaining pipe CS4N4B is SS-6.

8-CS-4B 8" Line list SS-6* 1250 psig 575* 550' (2)"

Type 316L (2)

For piping systems 12 inch nominal diameter or less and classified in accordance with Paragraphs 1.1, the pipe material is seamless stainless steel pipe per ASTM A-376 or A-312, Grade TP304 or TP316.

Per Referenco 25, Core Spray System is composed of TP316L material.

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7.3 CS System Weid Locations CI:ss 1 B-J weld locations for the CS system are included as Tables 7-2 ed 7-3. [7,20,21) 7.4 Core Spray System Degradation Mechanisms Evaluation The evaluation of the degradation mechanisms per the criteria in Table 2-2 for the recirculation system is presented in Appendix E. Highlights of this evaluation are provided below for all the mechanisms.

7.4.1 ThermalFatigue (TF) 7.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS) l The horizontal segments of the Core Spray System (Loops A and B) naar the reactor pressure v ssel (up to the containment isolation valves) are affected by the TASCS Degradation Mechanism due to the convective heating.

7.4.1.2 Thermal Transients (TT) l The Core Spray System is not affected by the Thermal Transient (TT) Degradation Mechanism l

due to the fact that no cold / hot water injection into hot / cold piping occurs (although the l operating temperature is greater than 270*F).

7.4.2 Stress Corrosion Cracking (SCC) 7.4.2.1 Intergranular Stress Conosion Cracking (IGSCC)

The majority of the Core Spray System is not affected by the IGSCC Degradation Mechanism due to the fact that all welds are classified as IGSCC Category A per Reference 25. The only cxception is the safe-end to piping welds on both loops (Welds NSB-SE, NSA-SE) which are classified as IGSCC Category D (non-resistant material, without stress improvement).

However, as mentioned in Section 1.3, these welds are classified as B-F and are thus, excluded from this evaluation.

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7.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC)

The Core Spray System is not affected by the TGSCC Degradation Mechanism due to the cbsence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34).

7.4.2.3 Extemal Chloride Stress Corrosion Cracking (ECSCC)

The Core Spray System is not affected by the ECSCC Degradation Mechanism due to the fact that the system is insulated with non-metallic insulation per Reg Guide 1.36 [5).

7.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The Core Spray System is not affected by the PWSCC Degradation Mechanism due to the f:ct that this system is not exposed to primary water with temperature conditions greater than 620'F and this system does not contain any inconel.

7.4.3 Localized Corrosion (LC) 7.4.3.1 Microbiologically Influenced Conosion (MIC) l The Core Spray System is not affected by the MIC Degradation Mechanism due to the fact that this system is not exposed to organic materials and/or is treated with blocides per the EPRI Water Chemistry Guld "nes [34).

7.4.3.2 Pitting (PIT)

The Core Spray System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines [34).

7.4.3.3 Crevice Corrosion (CC)

The Core Spray System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to-safe end weld, a B-F weld, excluded from this evaluation.

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7.4.4 Flow Sensitive (FS) 7.4.4.1 Erosion-Cavitation (E-C)

The in-scope piping for the Core Spray System is not affected by the EC Degradation Mechanism due to the fact that no cavitation sources exist.

7.4.4.2 Flow Accelerated Corrosion (FAC)

B:cause the Core Spray System is composed of stainless steel (TP316L), it was excluded -

from Reference 37, assuming that it is resistant to FAC due to its high chromium content l (>5%). Thus, the Core Spray System is not affected by the FAC Degradation Mechanism.

7.4.5 Water Hammer From Reference 36, the core spray system is not affected by the Water Hammer Degradation Mechanism.

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Table 7-2 ,

Weld Locations for Core Spray System Loop A

- 1, !

System Une WeM Wekt ' TF SCC LC FS ID Number Number Location TASCS TT IGSCC TGSCC ECSCC PWSCC nNC PfT CC EC FAC CS 8-CS-4A CS4A-MF6A Upstreamof N-58, Y N N N N N N N N N N/A -

Downstream of V14-14A CS 8-CS-4A CS4A-MF6 Safe End on N-5B Y N N N N N N N N N N/A- !

CS 8-CS-4A CS4A. MF50 Downstream side of Elbow, Y N N N N N N N N N N/A Upstream from Nozzle N-58 CS 8-CS-4A CS4A-MF5C Upstream side of Elbow, Y N- N N N N N N N N N/A Upstream from Nozzle N-58 CS 8-CS-4A CS4A-MFSB Downstream side of Elbow. Y N N N N N N N N- N N/A Downstream of Manual Valve V14-14A CS 8 CS-4A CS4A-MFSA Upstream side of Elbow, .

Y N N N N N N N N N N/A Downstream from K4&iual Valve V14-14A ]

CS 8CS-4A CS4A-MFS Downstream side of Manual Valve V14-14A Y N N N N N N N N- N N/A CS 8-CS-4A CS4A-F4 Upstream side of Manual Valve V14-14A Y N N N N N N N N N N/A -

CS 8-CS-4A CS4A-F3B Downstream of Check Valve V14-13A. Y N N N N N N N N N N/A~

Upstream from Manual Valve V14-14A CS 8-CS-4A CS4A-F3ADW Downstream of Check Valve V14-13A. Y N N N N N N N N N N/A Upstream from Manual Valve V14-14A CS 8-CS-4A CS4A-F3DW Downstream side of Check Valve V14-13A N N N N N N N N N N N/A CS 8-CS-4A CS4A-F2 Upstream side of Check Valve V14-13A N N N N N N N N N N N/A-CS 8-CS-4A CS4A-F1A Downstream of Penetration X-168, N N N N N N N N N N N/A Upstream of Check Valve V14-13A CS 8-CS-4A CS4A-F1 Downstream side of Penetratkm X-168, N N N N N N N N N N N/A Downstream from MOV CS-12A 8-CS-4A CS4A-F3A Upstream side of Penetration X-168, N N N N N N N N N N N/A CS Downstream of MOV CS-12A N N N N N N N N N N N/A CS SWA CS4A-F3 Downstream side of MOV CS-12A

Table 7-3 Weld Locations for Core Spray System Loop B System Line Weld Weld l Number Numtw Locs6on TASCS TT IGSCC TGSCC ECSCC PWSCC nt!C PIT CC EC FAC h ID Upstream from N-5A, Y N N N N N N N N N N/A CS 8-CS-48 CS4B-MF6A Downstream of elbow Upstream from N-5A, Y N N N N N N N N N N/A CS 8-CS-48 CS48-MF6 Downstream of elbow Downstream side of etbew, Y N N N N N N N N N N/A CS 8-CS 48 CS48-MF5D Upstream from N-5A Upstream skje of efbow, Y .N N N N N N N N N N/A CS 8 CS-48 CS49-MF5C Upstream from N-5A Downstream of Manual Valve V14-148, Y N N N N N N N N N N/A CS 8-CS-4B CS48-MF5B Downstream skie of elbow Downstream of Manual Valve V14-148, Y N N N N N N N N N N/A CS 8-CS43 CS4B-MFSA Upstream side of elbow Y N N N N N N N N N N/A CS 8-CS-4B CS48-MF5 Downstream side of Manual Valve V14-148 Upstream side of Manual Vatve V14-148 Y N N N N N N N N N N/A

> CS 8 CS-4B CS4B-F4 Downstream of Check Vahre V14-138, Y N N N N N N N N N N/A CS 8CS-4f3 CS48-F3B Upstream from ManualValve V14-148 Downstream side of elbow, Y N N N N N N N N N N/A CS 8-CS-48 CS48-F3ADW -

Downstream of Check Vafve V14-13B _

j Downstream side of Chedk Valve V14-138, N N N N N N N N N N N/A )

CS 8-CS-4B CS4B-F3DW Downstream of Penetration X-16A Upstream side of Check Valve V14-138, N N N N N N N N N N N/A CS 8CS4B CS48-F2 Downstream of Penetration X-16A Downstream side of elbow, N N N N N N N N N N N/A CS 8-CS-4B CS48-F1A Upstream of Check Valve V14-13B Downstream of Penetration X-16A, N N N N N N N N N N N/A CS 8-CS-48 CS48-F1 Upstream side of elbow Downstream side of Penetration X-16A, N N N N N N N N N N N/A CS 8.CS-48 CS48-F3A Downstream of MOV CS-128 N N N N N N N N N N/A CS SCS-4B CS48-F3. Downstream side of MOV CS-128 gN e

O

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

8.0 STANDBY LIQUID CONTROL 8,1 SLC System Description The standby liquid control (SLC) system provides a method to shut down the reactor from full power and maintain it subcritical during cooldown assuming the most reactive condition at any time in core life. The SLC tank is filled with enriched sodium pentaborate solution with a concentrate sufficient to shutdown the reactor without the aid of control rods. Injection into the reactor vessel will be performed only as a deliberate, long-term shutdown when the normal re*ctivity control system is not functioning satisfactorily. [22]

842 SLC System Class 1 Boundary l

The Class 1 portion of the SLC starts at the reactor vessel nozzle N-10 which is connected to line 1.5-SLC-11 (suction); ending at Valve V11-16. [3,23,28]

Tcble 8-1 lists the Class 1 lines within the SLC system and defines their operating and design conditions [4,5].

Table 8-1 SLC System Class 1 Lines and Operating / Design Conditions Line Pipe Size Pipe Pipe Design Design Op. Notes Number [4, 5,28] Thickness Material Pressure Temp. Temp.

[4. 28] [4, 5,28] [4,28] [4,28] [5]

1.5-SLC- 1.5" Sch.80 SS-6* 1275 psig 575* 85- (1) Design temp. for /

11 (1) 150* this line is 575* thru V11-17. Upstream, the design temp is 150*[28).

For those system classified in accordance with Paragraphs 1.1 and for pipe 12 inch nominal diam 0ier or less, the pipe material is seamless stainless steel pipe per ASTM A-376 or A-312, Grade TP304 or TP316.

8.3 SLC System Weld Locations Class 1 B-J weld locations for the Standby Liquid Control System are includea as Table 8-2.

[7,23]

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Checked By/Date:

File No. EPRI-116-301 Page 57 of 73 l

^ . "

e d 8.4 SLC System Degradation Mechanisms Evaluation The evaluation of the degradation mechanisms per the criteria in Table 2-2 for the SLC system is presented in Appendix F. Highlights of this evaluation are provided below for all the mechanisms.

8,4.1 ThermalFatigue (TF) 8.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS)

The horizontal piping adjacent to the reactor pressure vessel is affected by the TASCS Degradation Mechanism due to convection heating. Beyond weld F24, the vertical piping will cr:: ate a cold trap" that will eliminate the convective heating effect.

8.4.1.2 Thermal Transients (TT)

The Standby Liquid Control System is not affected by the Thermal Transient (TT) Degradation Mechanism due to the fact that no cold / hot water injection into hot / cold piping occurs (although the operating temperature is greater than 270*F) [5].

I 8.4.2 Stress Corrosion Cracking (SCC) 8.4.2.1 Intergranular Stress Corrosion Cracking (IGSCC) l The Standby Liquid Control System is affected by the IGSCC Degradation Mechanism due to the fact it is composed of susceptible material (either ASTM A-376 or A-316, Grade TP304 or TP316)[4,5]. (The Standby Liquid Control System does not fall under the requirements of Generic letter 88-01 due to the fact that the piping is less than 4".) In actuality, only line segments that are exposed to a temperature greater than 200*F would be susceptible to IGSCC. This would be the same piping that has been previously identified in Section 8.4.1.1 tbove (i.e., the horizontal section adjacent to the reactor.

8.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC)

The Standby Liquid Control System is not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34].

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. Checked By/Date:

File No. EPRI-116-301 Page 58 of 73

8.4.2.3 Extemal Chloride Stress Corrosion Cracking (ECSCC)

The Standby Liquid Control System is not affected by the ECSCC Degradation Mechanism due to the fact that the system is insulated with non-metallic insulation per Reg Guide 1.36 [5].

8.4. 2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The Standby Liquid Control System is not affected by the PWSCC Degradation Mechanism due to the fact that this system is not exposed to primary water with temperature conditions greater than 620*F and this system does not contah any inconel.

8.4.3 Localized Corrosion (LC) 8.4.3.1 Microbiologically Influenced Corrosion (MIC)

The Standby Liquid Control System is not affected by the MIC Degradation Mechanism due to the fact that this system is not exposed to organic materials and/or is treated with blocides per the EPRI Water Chemistry Guidelines [34).

8.4.3.2 Pitting (PIT)

The Standby Liquid Control System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines [34).

8.4.3.3 Crevice Corrosion (CC)

The Standby Liquid Control System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to-safe end weld, a B-F weld, excluded from this evaluation.

8.4.4 Flow Sensitive (FS) 8.4.4.1 Erosion-Cavitation (E-C)

The in-scope piping for the Standby Liquid Control System is not affected by the EC Degradation Mechanism due to the fact that no cavitation sources have been identified.

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 59 of 73

8.4.4.2 Flow Accelerated Corrosion (FAC)

Because the Standby Liquid Control System is composed of stainless steel (A-376 or A316, Grade TP304 or TP316)it was excluded from Ref 37, assuming that it is resistant to FAC due to its high chromium content (>5%). Thus, the Standby Liquid Control System is not affected by the FAC Degradation Mechanism.

8,4.5 Water Hammer From Reference 36, the standby liquid control system is not affected by the Water Hammer Degradation Mechanism, i

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(

Table 8-2 Weld Locations for Standby Liquid Control System '. , ,

Sysum une wem nwe ID Number Number Lacedon TASCS TT IGSCC TGSCC ECSCC PWSCC RNC PfT CC EC FAC -

SLC 1SSLC-11 SL11-F31 Downstream of Elbow. Y N Y N N N N N Y N WA Downstreem from DeerentU Pressure T-Branch (Lower)

SLC ISSLC-11 SL11-F30 Downstreamof Elbow.: Y N Y rd N N N Y N WA Upstream from DMerennel Pressure T-Brandi (Lower)

SLC 1SSLC-11 SL

1-F29 Downstream side of Elbow. Y N Y N N N N Y- N N'A Downstream from DMoren8al Pressure T-Brand) (Upper)

SLC 1SSLC-11 SL11-F28 Upstream side of Elbow. Y N- Y N N N N Y. N NA Downstrear, from Dhaal Pressure T-Branch (Upper)

SLC 1SSLC 11 SL11-F27 Downstream from Dee ental Pressure T-Branch (Upper) Y N Y N N N N N Y N N/A SLC iSSLC-11 SL11-F26 Upstream from DMerental Pressure T-Branch (Upper) Y N Y N N N N N Y N N/A SLC 1SSLC-11 SL11-F25B Downstream of Bend. .

Y N Y N N N N. N Y. N N/A Upstream from DMerennal Pressure T-Branch (Upper)

SLC 1SSLC-11 SL11-F25A Downstreamof Bend. Y N Y N N N N N Y- N N/A Upstresin from DMerental Pressure T-Branch (Upper)

SLC 1SSLC-11 SL11-F25 Downstream side of Elbow. Y N Y N N N N N Y N- N/A Upstream from DMerenEal Pressure T-Branch (Upper)

SLC 1SSLC-11 SL11-F24 Upstream side of Ebow, Y N Y N N N N N Y N N/A Upstream from DMerential Pressure T-Branch (Upper)

SLC iSSLC-11 SL11-F23 Downstream side of Elbow, . N N N N N N N N Y- N N/A Downstroom of Manual Valve V11-18 SLC ISSLC-11 SL11-F22 Upstream side of Elbow, N N N N N N N N Y N N/A Downstream of Manuel Valve V11-18 1SSLC-11 , SL11-F21B Downstream side of Flange Conrec8on, N N N N N N N N Y N N/A SLC Downstream of Manual Valve V11-18 SLC 1SSLC-11 SL11-F21A Upstream side of Flange Connecton. N N N N N N N N Y N N/A Downstream of Manual Valve V11-18 '

1SSLC-11 SL11-F21 Downstream side of Manual Valve V11-18 N N N N N N N N Y N N/A SLC SL11-F20 Upstream side of Manual Valve V11-18 N N N N N N N N Y N N/A SLC 1SSLC-11 1SSLC-11 SL11-F19 Downstreem side of Check Valve V11-17 N N N N N N N N Y N N/A SLC SL11-F18 Upstream side of Chedt Valve V11-17 N N N N N N N N Y N N/A SLC 1SSLC-11 Dcenstream side of Elbow. N N N N N N N N Y N N/A -

SLC 1SSLC-11 SL11-F17 Upstream from Check Valve V11 17 Upsteam sWe of Elbow. N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F16 Upstream fruit Check Valve V11-17 Downstream side of Elbow. N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F15 Downstream from Containment Wall Penetration X-42 SL11-F14 Upstream side of 851 bow. N N N N N N N N Y N N/A SLC 1SSLC-11 Downstream from Coritainment Wall Penetra60n X42 Downstream of Drywee Penetracon X-42 N N N N N N N N Y N N/A -

SLC 1SSLC-11 SL11-F13 Upstreamoownstroom side of Drywell Penetragon X-42 N: N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F12 Downstream from Restraint SLC-H47, N- N N- N N N N N Y- N N/A SLC 1SSLC-11 SL11-F11 Upstream from Drywell Penetra8on X-42

Tgble 8-2 cont.

1 System LJne Weld Weld Lmtion TASCS TT IGSCC TGSCC ECSCC PWSCC nttC PIT CC EC FAC ID Number . Namber ~

N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F10 Downstream from Restraint SLC-H47 Upstream from Drywell Penetration X42 N N N N N N N N Y N N/A ;

SLC 1SSLC-11 SL11-F9H Downstream side of Couphng, l

Upstream of Restraint LC-H47 N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9G Upstream side of Couphng, j l Upstream of Restraint SLC-H47 hwer,ani side of Elbow, N N N N N N N N Y N N/A !

SLC 1.5-SLC-11 SL11-F9F Upsbeam from Coupling N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9E Upstream side of Erbow, Upstream from Coupling Downstream side of Flange Connection, N N N N N N N N Y N N/A ' ~

SLC 1SSLC-11 SL11-F9D

' Do',nstream of Restraint SLC4tD47 N N N N N N N N Y N N/A SLC 1.5-SLC-11 SL11-F9C Upstream side of Flange ConnecDon, Downstream of Restraint WAfD47 N N N N N N N N Y N N/A SLC 1.5-SLC-11 SL11-F98 Downstream of Flow Swit& FSH 11-54, Dvoistream of Restraint SLC-HD47 N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9A Downstream of Flow Switch FSH 11-54, Downstream of Restraint SLC-HD47 N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9K Downstream of Flange Co.ini, Upstream from Flow Switch FSH-11-54 N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9J Downstream of Flange Cwum.Lu%

Upstream from Flow Switch FSH-11-54 N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F9 Downstream of Elbow, Dumstream side of Flange ConnecDon N N N N N N N N Y 7 N/A SLC 1SSLC-11 SLt1-F8 Downstream of Elbow, .h Upstream sirte of Flange Ccru +cuon N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F7 Downstream Side of Elbow, Dv-retream of Test Cm ma;wi Branch N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F6 Upstream side of Elbow, Downstream of Test CwiG Branch N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F5 Downstream of SLC Check Va!ve V11-16, Dumbe. m of Test Cwim.L, Brane -

N N N N N N N N Y N N/A SLC 1SSLC-11 SL11-F4 Downstream of SLC Check Valve V11-16, Upstream of Test Cusi, L> Brane N/A N N N N N N N N Y N SLC 1SSLC-11 SL11-F3 Downstream side of SLC Check Valve V11-16 N N N N N N N N Y N N/A SLC 1SSLC-11 SL-40N 1 Weld on Test Connechon B amL duwnstream from Check Valve V11-16 N/A N N N N N N N N Y N SLC 1SSLC-11 SL-409-F2 Weld on Test Connechon Branch downstream from Check Valve V11-16

. , . . , , _ i......

,.,......_,w _

..7.- . . -. ---_. ..r. _. .. _;, . .,.,,__. ,.,_.. _ .__.____ _ _ . . _ . , , ,

9.0 REACTOR WATER CLEANUP 9.1_ Reactor Water Cleanup System Description The Reactor Water Cleanup (RWCU) system is designed to maintain high reactor water purity during all phases of operation, including startup, normal operation, shutdown, refueling and standby. The RWCU system is placed into operation before reactor startup and is in operation through all modes of reactor operation. RWCU retum to the vesselis through the feedwater system. [24]

9.2 Reactor Water Cleanup System Class 1 Boundary The RWCU system (Line 4* CUW-18) branches off from Line 20-RHR-32 of the reactor r: circulation system (Loop A), it includes all of Line 4-CUW-18 (to Valve V12-18), which branches off to Line 2-CUW-19. Line 2-CUW-400 feeds into Line 2-CUW-19. The Class 1 portion of Line 2-CUW-400 ends at Valve V2-50. [6).

Tcble 9-1 lists the Class i lines within the RWCU system and defines its operating and design conditions (4,5].

Table 9-1 RWCU System Class 1 Lines and Operating / Design Conditions Line Pipe Size Pipe Pipe Design Design Op. Notes Number [4,5] Thickness Material Pressure - Temp. Temp.

[4] [4.5] [4] [4] [5]

4-CUW-18 4" LTe List SS-6* 1250 psig 575* 550*

2-CUW-19 2" Lin e List SS-6* 1250 psig 575* 550*

2-CUW- 2" (1) ? SS-6* 1250 psig 575* 550' (1) Ref. 5 does not 400 (1) report CUW-400; assumed CUW-40A.

For those system classified in accordance with Paragraphs 1.1 and for pipe 12 inch nominal diameter or less, the olpe material is seamless stainless steel pipe per ASTM A-376 or A-312. Grade TP304 or TP316.

Revision: 0 Prepared By/Date:

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File No. EPRI-116-301 Page 63 _of 73

9.3 RWCU System Weld Locations Class 1 B-J weld locations for the RWCU system are included as Table 9-2. [6,7) 9.4 RWCU System Dep.adation Mechanisms Evaluation The evaluation of the degradat on mechanisms per the criteria in Table 2-2 for the RWCU system is presented in Appendix G. Highlights of this evaluation are provided below for all the mechanisms.

9.4.1 ThermalFatigue (TF) 9.4.1.1 Thermal Stratification, Cycling, and Striping (TASCS)

The RWCU System is not affected by the TASCS Degradation Mechardsm due to the fact that no mixing of hot / cold fluids, leakage or two phase flow, etc., can occur.

9.4.1.2 Thermal Transients (TT)

The RWCU System is unaffected by the Therrnal Transient (TT) Degradation Mechanism due to the fact that no cold / hot water injection into hot / cold piping occurs.

C.4.2 Stress Corrosion Cracking (SCC) 9.4.2.1 Intergranular Stress Cormsion Cracking (IGSCC)

The RWCU System is not affected by the IGSCC Degradation Mechanism due to the fact that all welds are classified as IGSCC Category A per Reference 25.

9.4.2.2 Transgranular Stress Corrosion Cracking (TGSCC)

The RWCU System is not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per VY's implementation of the EPRI Water Chemistry Guidelines [34).

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page_ 64 of 73

9.4.2.3 Extemal Chloride Stress Corrosion Cracking (ECSCC)

The RWCU System is not affected by the ECSCC Degradation Mechanism due to the fact that the system is insulated with non-metallic insulation per Reg Guide 1.36 [5).

9.4.2.4 Primary Water Stress Corrosion Cracking (PWSCC)

The RWCU System is not affected by the PWSCC Devadation Mechanism due to the fact that this plant is not exposed to primary water with temperature conditions greater than 620*F cnd this system does not contain any Inconel.

9.4.3 Localized Corrosion (LC) 9.4.3.1 Microbiologically Influenced Corrosion (MIC)

The RWCU System is not affected by the MIC Degradation Mechanism due to the fact that this system is exposed to an operating temperature greater than 150*F [5).

9.4.3.2 Pitting (PIT)

The RWCU System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to low flow conditions or PIT initiating contaminants (per VY's implementation of the EPRI Water Chemistry Guidelines [34]).

9.4.3.3 Crevice Corrosion (CC)

The RWCU System is not affected by the Crevice Corrosion (CC) Degradation Mechanism due to the fact that there are no thermal sleeves located in the in-scope piping.

9,4.4 Flow Sensitive (FS) 9.4.4.1 Erosion-Cavitation (E-C)

The RWCU System is not affected by the EC Degradation Mechanism due to the fact that no cavitation source exists in the system and the operating temperature is greater than 250*F [5].

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File No. EPRI-116-301 Page_ 65 of 73

9.4.4.2 Flow Accelerated Corrosion (FAC)

The RWCU System is a part of W's FAC program (37). As discussed in Section 1.3, program r;sults have indicated that these systems are not susceptible to FAC.

9.4.5 Water Hammer From Reference 36, the RWCU system is not affected by the Water Hammer Degradation Mechanism.

l l

i Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRJ-116-301 Page 66 of 73 I

l l

Table 9-2 !

Reactor Water Cleanup Weld Locations -

System Line Weld Weld TF SCC LC FS l TASCS :TT IGSCC TGSCC ECSCC PWSCC nflC PIT CC EC FAC ~~ '

10 Number Number Location RWCU 4-CUW-18 CU18-10 Downstream of Branch Connection Frw RHR 20* RHR-32 N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-9 Upstream Side of Valve V12-46, N N N N N N N N N N N/A Downstream of Brand Connection from RHR RWCU 4 CUW-18 CU18 8 Downstream Side of Valve V12-46, N N N N N N N N N N N/A Downstream of Branch Connechon from RHR RWCU 4-CUW-18 CU18-7 Downstream of Valve V12-46, N N N N N N N N N N N/A Upstream of Branch Connecuan to 2" CUW RWCU 4-CUW-18 CU19-FW1 Upstream from Branch Connecbon from 4* CUW-18

N N N N N N N N N N N/A RWCU 2-CUW-19 CU19-FW2 Upstream from Branch Connecbon from 4* CUW-18 N N N N N N N N N N N/A RWCU 2-CUW-19 CU19-FW3 Upstream from Branch Connechon from 4* CUW-18 N N N N N N N N N N N/A RWCU 2-CUW-19 CU19-FW4 Downstream side of cotgAng, N N N N N N N N N N N/A Upstream of Branch ConnectKm from 4* CUW-18 RWCU 2-CUW-19 CU19-FWS Downstream skje of coupling, N N N N N N N N N N N/A Upstream of Branch Connecnon from 4* CUW-18 RWCU 2-CUW-19 CU19-F11 Downstream side of Vatve V2-99 N N N N N N N N N N N/A RWCU 2-CUW-19 CU19-F10 Upstream skie of Valve V2-99 N N N N N N N N N N N/A 2-CUW-19 CU19-F9 Upstream of Vatve V2-99 N N N N N N N N N N N/A RWCU RWCU 2-CUW-19 CU19-F8 Upstream of Vatve V2-99 N N N N N N N N N N N/A RWCU 2-CUW-19 Cut 9-F7 Upstream cf Vahre V2-99, N N N N N N N N N N N/A Downstream of B and Conr'echon to CU-400 CU19-F6 Upstream of Valve V2-99, N N N N N N N N N N N/A RWCU 2-CUW-19 Downstream of Branch Connection to CU-400 RWCU 2-CUW-19 CU19-F5 Upstream of Valve V2-99, N N N N N N N N N N N/A Doimstream of Brand Connection to CU-400 CU19-F4 Upstream of Valve V2-99, N N N N N N N N N N N/A RWCU 2-CUW-19

/ Downstream of Brand Connection to CU-400 CU19-F3 Upstream of Valve V2-99, N N N N N N N N N N N/A RWCU 2-CUW-19 Dv-stiid=n of Branch Connechon to CU-400 CU19-F2 Upstream of Valve V2-99, N N N N N N N N N N N/A RWCU 2-CUW-19 Downstream of Brand Connecnon to CU-400 CU19-F1 Downstream of Branch Connection to CU-400 N N N N N N N N N N N/A RWCU 2-CU'N-19 CU400-F10 Downstream side of connection to 2* CUW-11 N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-F11 Upstream side of V249 N N N N N N N N N N N/A RWCU 2-CUW-400 Downstream side of V249 N N N N N N N N N N N/A RWCU 2-CUW-400 CU40 M 12 Upstream side of V2-50 N N N N N N N N N N N/A RWCU , 2-CUW-400 CU40 M 13 Connecbon to bottom of RPV N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-F1 Downstream of RPV N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW1 N N N N N N N N N N N/A RWCU 2-CUW-400 CU404FW2 Downstream of RPV N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW3 Upstream side of coupling N N N N N N N N N N N/A RWCU 2-CUW-400 CU404FW4 Downstreamsideof axrpling N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW5 Downstreamof RPV N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW6 Downstream of RPV N N N N N N N N N N N/A RWCU 2-GUW-400 CU400-FW7 Downstream of RPV

System Line Weld Weld TF SCC LC FS

!D Number Number Location TASCS TT IGSCC TGSCC ECSCC PWSCC NIC PIT CC EC FAC CU400-FW8 Downstream of RPV N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW9 Upstream side of connection to 2* CUW-11 N N N N N N N N N N N/A RWCU 2-CUW-400 CU400-FW10 Upstream side of coupling N N N N N N N N N N r#A RWCU 2-CUW-400 2-CUW-400 CtJt00-F9 Downstieam side of coupling N N N N N N N N N N N/A RWCU RWCU 4-CtIN-18 CU18-6 Downstream of Branch Connecten to 2* CUW

N N N N N N N N N N N/A 4-CUW-18 CU18-5 Upstream side of Valve V12-15 N N N N N N N N N- N N/A j RWCU Downstream of Brand Connection to 2* CUW RWCU 4-CUW-18 CU18-4 Downstream side of Valve 12-15 N N N N N N N N N N N/A Downstream of Brand Connecbon to 2* Cl#/

4-CUW-18 CU18-3 Upstream side of Elbow, N N N N N N N N N N N/A RWCU Downstream of Valve V12-15 Downstream side of Elbow, N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-2 Downstream of Valve V12-15 Upstream side of Elbow, N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-1 Upstream of Restraint CU-3 Downstream side of "Jbow, N N N N N N N N N N N/A RWCU 4-CtN/-18 CU18-F13 Upstream of Rest; snt CU-3 upstream side of Elbow, N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-F14 Downstream of Restraint CU-3 Downstream side of Elbow, N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-F15 Downstream of Spring Hanger CU-4 Downstream from Spring Hanger CU-4, N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-F16 Upstream of Spring Hanger CU-5 Downstream from Spring Hanger CU-8, N N N N N N N N N N N/A RWCU 4-CUW-1'3 CU18-F17 Upstream from Penetration X-14 Upstream of Penetration X-14 N N N N N N N N N N N/A RWCU 4-CUW 18 CU18-F18 N N N N N N N N N N N/A RWCU 4-CUW 18 CU18-F23 Dovmstream of Penetration X-14 at Tee Connectson Upstream side of Valve V12-18 N N N N N N N N N N N/A RWCU 4-CUW-18 CU18-F25 Downstream of Penetration X-14

Not Indoded in Vermont Yankee N560 Code Case Welds St Flie: EPRI-116-507.

e e

10. REFERENCES

1) ASME Code Case N-560, "Altemative Examination Requirements for Class 1, Category B-J Piping Welds,Section XI, Division 1", Supp. 6 - NC, Approval Date: August 9, 1996, SI File: EPRI-116-203.

2) Procedure No. OP 2110. " Reactor Recirc System", Rev. No. 29, issue Date 10/07/96, SI File: EPRI-116-505 (A).

3) Vermont Yankee Nuclear Power Etation Dwg. G-191167, " Flow Diagram Nuclear Boiler", July 26,1968, SI File: EPRI-116-501.

4) BWR-QC-10, "Boller Water Reactor Ebasco Specification for Piping, Piping Components, Hangers and Supports for Station Piping Systems", Issued 9/15/68, SI File: EPRI-116-506.

5) VYNP-lil-1-1, Ebasco Specification, " Insulation", Rev. 2, SI File: EPRI-116-506.

6) Vermont Yankee Nuclear Power Station Dwg. ISI 5920-6622 Sh.1/3, " Reactor Recirc.

(RR) Residual Heat Removal (RHR) and Reactor Cleanup Water (RCUW) Systems-Drywell", SI File: EPRI-116-502.

7) Vermont Yankee N560 Code Case Welds, SI File: EPRI-116-507.

8) Procedure No OP 2113, " Main and Auxiliary Steam", Rev. No.18, Issue Date 10/07/96, SI File: EPRI-116-505 (D).

9) Procedure No. OP 2121, " Reactor Core Icolation Cooling System", Rev. No. 27, Issue Date 8/15/96, SI File: EPRI-116-505 (M).

10) Procedure No. OP 2120, "High Pressure Coolant injection System", Rev. No. 25, issue Date 12/07/95, SI File: EPRI-116-505 (1).

11) Vermont Yankee Nuclear Power Station Dwg. ISI RPV-105, " Main Steam (MS) Reactor Core Isolation Cooling (RCIC) Reactor Building (Drywell/ Steam Tunnel)", SI File: EPRI-116-502,

12) Vermont Yankee Nuclear Power Station Dwg. ISI-HPCI-Part 2, "High Pressure Coolant injection Reactor Building (HPCI) Part 2", EPRI-116-502.

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 69 of 73

13) Vermont Yankee Nuclear Power Station Dwg. ISI-FDW-Part SA, " Main Stearn Tunnel-Feedwater Drywell (FDW) Part 5A", Si File: EPRI-116-502.

14) Vermont Yankee Nuclear Power Station Dwg. ISI-FDW-Part 5, "Feedwater Drywell-Main Steam Tunnel (FDW) Part 5", SI File: EPRI-116-502.

15) Procedure No. OP 2124, " Residual Heat Removal System", Rev. No. 42, Issue Date 5/6/97, SI File: EPRI-116-505 (K).

16) Vermont Yankee Nuclear Power Station Dwg.1S1-5920-9283, " Residual Heat Removal (RHR) Part 5", Si File: EPRl-116-502.

17) Vermont Yankee Nuclear Power Station Dwg. ISI-5920-9287, " Residual Heat Removal (RHR) Part 7", SI File: EPRI-116-502.

18) Vermont Yankee Nuclear Power Station Dwg. ISI-RHR-Part 11 Sh.1/5, " Residual Heat Removal Drywell Access Enclosure (RHR) Part 11", Si File: EPRI-116-502.

19) Procedure No. OP 2123, " Core Spray", Rev. No. 26, Issue Date 10/18/96, SI File:

EPRI-116-505 (L).

20) Vermont Yankee Nuclear Power Station Dwg.1S1-5920-9206, " Core Spray (CS) Part 2",

SI File: EPRI-116-502.

21) Vermont Yankee Nuclear Power Station Dwg. ISI-5920-9211, ,

Core Spray (CS)

Part 6", SI File: EPRI-116-502.

22) Procedure No. OP 2114," Operation of the Standby Liquid Control System", Rev. No.

21, Issue Date 10/31/95, SI File: EPRI-116-505 (E).

23) Vermont Yankee Nuclear Power Station Dwg. ISl-SLC-Part 4, " Standby Liquid Control Reactor Building (SLC) Part 4", SI File: EPRI-116-50'2.

24) Procedure No. OP 2112, " Reactor Water Cleanup System", Rev. No. 27, Issue Date, 10/07/96, SI File: EPRI-116-505 (C).

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 70 of 73

25) Vermont Yankee Document Number LAl878, NVY 90-026, Letter, M. B. Fairtile (USNRC) to L. A. Trembley (VYNPC),

Subject:

Review on Response to Generic Letter (GL) 88-01, *NRC Position on IGSCC in BWR Stainless Steel Piping", Date 2/14/90, Sl File EPRI-116-508.

26) Vermont Yankee Dwg. No. G-191174, Sheet 1 of 2, " Flow Diagram: Reactor Core Isolation System", Rev. 32,6/29/95, SI File: EPRI-116-501.

27) Vermont Yankee Dwg. No. G-191172, " Flow Diagram: Residual Heat Removal System", Rev. 49,8/25/95, SI File: EPRI-116-501.

28) Vermont Yankee Dwg. No. G-191171, " Flow Diagram: Standby Liquid Control System",

Rev.19,1/24/97, Sl File: EPRI-116-501,

29) Vermont Yankee Dwg. No. G-191168, " Flow Diagram: Core Spray System", Rev. 32, 1/31/97, SI File: EPRI-116-501.

30) Not Used in this Calculation Package.

31) " Recirculation System, " E.K. - G.E., SI File: EPRI-116-506.

32) 6 BWR General Description of Boiling Water Reactor, General Electric Nuclear Energy Divisions,15th Printing, March,1976.

33) Yankee Nuclear Calculation Number NSD-020, " Yankee Nuclear Services Division Calculation / Analysis for Degradation Mechanism Evaluation Maine Yankee", SI File:

l EPRI-116-614.

I

34) Excerpts from VYN FSAR Sections 3.6,4.6,11.7 (Implementation of EPRI water Chemistry Guidelines ) St File: EPRI-116-510.

35) Structural Integrity Report SIR-96-097, " Review of Degradation Mechanisms in EPRI Risk-informed Inservice Evaluation Procedure", Rev. O,10/4/96.

36) VYN97XX1 (Water Hammer Plant Experience)

37) Vermont Yankee Nuclear Power Corporation, Vermont Yankee - Piping F.A.C.

Inspection Program - Revision 2, " Piping Flow Accelerated Corrosion Inspection Program Manual", Dated 6/1/95, Si File: EPRI-116-509.

38) VYN97XX2 (FAC Plant inspection Results)

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 71 of 73 l

. . 1 I

39) Telecom of 6/1/97 (O'Regan (VY) and C. Markovits (SI))

Subject:

Insulation Specification, EPRI Water Chemistry Guidelines, Si File: EPRI-116-103.

40) EPRI TR-106706, " Risk-Informed Inseivice Inspection Evaluation Procedures," June 1996.

/

J t

A i

Revision: 8/6/97 Prepared By/Date:

Checked By/Date:

File No. EPRI-116-301 Page 72 of 72

, i

, I i

l l

l APPENDIX A DEGRADATION MECHANISM EVALUATION FOR REACTOR REClRCULATION SYSTEM Revision: o f.

Prepared By/Date:

Checked By/Date:

File No. EI'RI-116-301 l' age A-1 of A-4 I

Degradation htecha:Isrs Assessment Worksheet Conclu:lons Cisk Segment No.

Attributes to t>e Considered Remarks No.

-* l *" l ** l "^

TASCS-1 hps > 1 inch, and x a a a 1ASCS 2 pipe segment has a slope < 45* from horltontal(includes elbow g a x a of too into a vertica! pipe), and TASCS-3-1 potential exists for low fJow In a pipe secton connected to a a x a a Does not consider vent and decin Iones.

component allowing mix}ng of hot and cold fluids, or TASCS 3 2 potential exists for Joakage flow past a valve (I e., in-Jeakage, O x D D Does not consider vent and drain lines.

out-leakage, crossJoakage) allowing mixing of hot and cold fluids, of TASCS-3-3 potential exists for convection heating in dead ended pipe D x a D Does not considor vent and drain knes.

seckons connected to a source of hot fluid, or TASCS 34 potential exists for two phase (steam / water) flow, or O x a O Does not consider vent and drain knes.

TASCS-3-6 potential exists for turbulent penetration in branch pipe O x a a Does not considor vent and draln unes.

connected to header piping conta}ning hot Duid with high turbulent flow, and TASCS-4 calculated or measured AT > $0*F, and C D x L, Does not considor vont and drain lines.

TASCS-5 Richardson number > 4 0 o a x 0 Does not consider vont and drain lines.

in conclusion, the Redrculation System is not affected by the TASCS Degradation Mechanism (exclusive of vent and drain lines) due to the absence of stratification, leakage, two-phase flow, etc.

TT 11 operaung temperature > 270*F for stelnless stool, or x a a o TT 12 c;n> rating temperature > 220*F for carbon stool, and a 0 0 a potential for relatively rapid temperature changes includ;ng TT 21 cold waterirtloction into hot pipe segment, or x a a o First neld aear RHR Connection (va!>e) for RHR injection (Wold RR-A-D-13 Loop A; t%old RR B-D-13 Loop B).

TT 2-2 hot water b.lection into cold pipe segment, and x 0 g a First sold near RHR Connection (valve) for RHR Ir\lection (Weld RR A-D 13 Loop A; Wold RR-B-D-13 Loop B).

TT 3-1 l ATl > 200*F for stainless steel, or 0 x a a TT 3-2 l ATl > 150*F for carbon steel, or a D a a 1T33 l l ATI > AT allowable (applocable to both stainless and carbon) o o a a in conclus6on, the first weld (RR A D-13 tor Loop A; RR-D-D 13 tor Loop D) near the RHR connection is affected TT by the RHR injection trans6ent.

IGSCC B-1 evaluated in accordance with existing plant 9GSCC program per x a a a all welds are IGSCC Category A NRC Generic Letter 88-01 ICSCC-P 1 operating temperature > 200*F, and o a o x N/A epplies only to P%Rs.

IG SCC-P-2 susceptible material (carbon content n 0 035%), and a o a x IVA applies only to PWRs.

IGSCC-P-3 tensile stress (including residual stress)is present, and o a o x N!A applies only to PwRs.

IGSCC-P-4 oxygen or oxidizing species are present a o 0 x IWA applies only to PARS.

OR IGSCC-P-5 operating temperature < 200*F, the attributes above apply, and a o a x N/A applies only to PwRs.

IGSCC-P-6 enttiating contaminants (e g., thiosulfate, nuoride, chloride) are a o a x IVA apphes only to P%Rs.

also required to be present in condusion, the Rodrculation System is not affected by the IGSCC Degradation Mechanism due to the fact that att wolds have been classified as Category A under NRC Generic Letter 88-01.

I 1

Degradation Mechanism Assessment Worksheet Conclusions Risk segment No.

No. l Attributes to be Considered

l ** l

l "* Remarks TGSCC1 operstmg ternporature > 150*F, and x a a a TGSCC 2 tensile stress (includong residual stress) is present, and x a a a TGSCC 31 hahdes (e g., Ituonde, chlande) are present, or a x a a Irnpurities are controIIedper LPRI TGSCC 3-2 caustic (NaOH)is present, and a x 0 a water chemistry guidehnes.

TGSCC 4 oxygen or oxidizing species are present (only required to be x 0 0 a present in corgunction wAlalides, not required wkaustic) in condusion, the Redrculation System is not affected by the TGSCC Degradabon Mechanism due to the absence of hahdes and causbcs, per W's implementabon of the EPRI Water Chemistry Guidehnes.

ECSCC-1 operating temperature > 150*F, and x a a a ECSCC.2 tensIIe stress is present, and x 0 o a ECSCC-3-1 an outside piping surface is within fin diameters of a probable a x a a W comphes wnh Reg Guide 1.36 leak path le g., valve stems) and is conred with non-metalkc insulation that is not in compliance with Reg. Guide 1.36, or ECSCC-3-2 an outsido piping surface is exposed to setting from chloride a x a a bearing environments (e g., seawater, brackish water, brine)

In condusion, the Recirculabon System is not affected by the ECSCC Degradabon Mechanism due to the tact that the system is insulated with non-rmtitic insulation per Reg Guide 1.36.

PWSCC1 piping materialis inconel(Alloy 600), and a x a O l

l PWSCC 2 exposed to primary water at T > 620*F, and a x a a PWSCC-3-1 the materialis mill-anneated and cold nwked, or a a x a PWSCC 3-2 cold worked and welded without stress relief a a x a in condusion, the Recirculation System is not affected by the PWSCC Degradabon Mechanism due to the tact that the system is not exposed to prtrmry water at T> 620*F and is not composed of inconel.

MIC 1 operating temperature < 150*F, and a x a a MIC-2 kw orintermittent flow, and a a x a MIC-3 pH < 10, and a a x a MIC-41 presenceAntrusion of organic material 'e g., raw water system), a a x a or MIC42 wator source is not treated w. biocides (e g., refueling water tank) O a y a

~

in condusion, the Recirculation System is not affected by the MIC Degradation Mechanism due to the fact that this system lsEtposed to an operating tmperature greater than 150*F, PIT 1 potentialexists for kw flow, and x a a a Excludes vent and drain lines.

PIT-2 oxygen or oxidizing species are present, and x 0 a a Excludes vent and drain lines.

PIT 3 initiating contaminants (e g., fluoride, chloride) are present a x a a Wmeets EPRI Water Chemistry Guidelines.

Excludes vent and drain lines.

In condusion, the Redrcutabon System is not affected by the PIT Degradation Mechanism (exdusive of vent and drain lines) due to the fact that this system is not exposed to PIT initiating contaminants, as W comphes with EPRI Water Chemistry Guidelines.

CC-1 credce condition exists (e g., thermal sleeves), and a x a a .-

CC 2 operating temperature > 150*F, and x a a a CC-3 oxygen or oxidizing species are present x a a a in condusion, the Redrculation System is not affected by the CC Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. The weld INation corresponding to this location is the nozzle-to-shte end weld, a B-F weld, exdudad from this evaluation.

E41 existence of cavitation source (I e., throttling orpressure O x a a

' educing vales or orifices)

E42 operating temperature < 250*F, and a y a a E C-3 tiow present > 100 hrstyr, and a a y a

\\ u

4 4 DegradeNon Mechenlem Assessment Worksheet Concluelens Miek Segment No.

No. Aterbreos to be Considered * ** *

Memerks E-C-4 WocMy > 30 Ws, and a o x a E45 (Po P,)/ AP < $ 0 0 y a in condusion, the Recirculat6on System is not affected by the EC Degradabon Mechanism due to the absence of a cavitauon source and due to the fed that the operahng temperature is gre stor than OLO'F, FAC 1 evaluated in accordance wNh existing plant FAC program a x g a not kt FAC program: steintess steel.

In condusion, the RodrculaUon System is not affected by the FAC Degradation Mechanism due to the fact that the system is not indoded in the FAC program (I e., the system is composed of stainless steel). -

Water o y a a Hammer

- -_--_a-----a.--.-- -_.- --_ - -- - - - - -----------u- x---- -. - - - - - - - - - - -

1 APPENDIX B DEGRADATION MECHANISM EVALUATION FOR MAIN STEAM, RCIC AND HPCI SYSTEMS l

5 Revision: O PrT Zred Py/Date:

fliecked Hy/Date:

File No. EPRI-116-301 Page B-1 of B-7 i l

l DEGRADATION MECHANISM EVALUATION FOR MAIN STEAM AND MAIN STEAM DRAIN Revision: 0 Prepared By/Date: .

Checked By/Date:

File No. EPRI-116-301 Page B-2 of _-7

e DegradaUon Mechanism Asseosment Worksheet Conclusions Risk Segment No, No. l Attributss to be Considered

*l

l wl* Remarks TASCS 1 res > 1 inch, and x a a a TASCS-2 pipe segment has a slope < 45' from hortiontal(Mcludes elbow x a a a or toe into a wrticalpipe), and TASCS 3-1 potential exists for low flow M a pipe section corcocted to a a a a x No water exists; steam qstem (both MS and component allowing mixing of hot and cold fluids, or MSD).

TASCS 3 2 potential exists for loakage flow past a valve (Le., in-leakage, a a O x No water exists; steam system (both MS and out-leakage, cross-leakage) allowing mixing of hot and cold MSD). fluids, or TASCS-3 3 potential exists for convection heating in dead-ended pipe a a O x No water exists; steam system (both M3 and sections connected to a source of hot fluid, or MSD). TASCS 3-4 potential exists for two phase (steam / water) flow, or x a a X No water exists; steam system. MSD collects condensate during startup. TASCS-3-5 potential exists for turbulent penetration in branch pipe a a o x No water exists; steam system. connected to headerpiping containing hot *luid with high turbulent flow, and TASCS 4 calculated or measured AT > SO'F, and a a a a TASCS-5 Richardson number > 4.0 0 a a a in conclusion, the Main System is not affected by the TASCS Degradabon Mechanism due to the fact that it is filled with steam and no TASCS mechanism can occur, Conversely, the MSD system is affected by the TASCS Degradation Mech 1nism due to the existence of the steamtwater interface (condensate collection during startup). TT 11 operating temperature > 270*F for stainless steol, or a a a a TT 1-2 operatmg temperature > 220*F for carbon steel, and x a 0 0 l potential for relatively rapid temperature changes including TT f cold water dryection into hot pipe segment, or O x a a No rapid transient events. 774 4 hot waterlifection into cold pipe segment, and a x 0 0 No rapid transient events. TT 3-1 l ATI > 200'F for stainless steel, or a a a x TT-34 l ATl > 150*F for carbon steel, or x a o a TT-3-3 l ATl > ATallowable (applicable to bcth stainless and carbon) O O O a in condusion, the Main Steam System is not affected by the thermal transient (TT) Degradabon Mechanism due to the absence of rap 6d temperature changes from cold / hot injections from rapid transient events. It should be noted that etthough the Main Steam systom is not affected by thermal fatigue, the Main Steam System could be affected by mechanical fatigue due to the MSRV actuation. IGSCC-B 1 evaluated in accordance with existing plant IGSCC program per a x a a not part of 88-01 program since carbon steel NRC Generic Letter 88-01 IGSCC-P-1 operating temperature > 200*F, and a a a x WA applies only to PWRs. IGSCC-P-2 susceptible m:lertal(carbon ccatent a 0 035%), and a a a x WA applies only to PWRs. IGSCC-P-3 tensile stress (Mcluding residual stress)is present, and a a O x WA applies only to PWrd IGSCCP-4 oxygen or oxidizing species are present a a a x WA applies only to PWRs. OR IGSCC-P-3 operating temperature < 200*F, the attributes abon apply, and a a a x WA applies only to PWRs-IGSCC-P-6 initiating contaminants (e g., thiosulfate, fluoride, chloride) are a a O x WA applies only to PARS. also required to be present in conclusion, the Main Steam System is not affected by the IGSCC Degradation Mechanism due to the fact that the piping is composed of carbon eteel, a material that is not susceptible to IGSO4. TGSCC-1 operating temperature > 150*F, and x a a a TGSCC-2 tensile stress (including residual stress) is present, and x a a a TGSCC-3-1 halides (e g., fluorido, chloride) are present, or a x a a Impurities are controIIedperEPRI TGSCC-3-2 caustic (NaOH)is present, and a x a a water chemistry guidelines. TGSCC-4 oxnen or oxidizing species are present (only required to be x a a a present in corgunction wihalides, not required witaustw) l

                                                                                                                                        .        e i

i , I Degradation Mechanl:m Assessment Worksheet Conclusions Risk segmentNo. No. Attributes to be Considered Remarks l

l *** l ** l ***

in condusion, the Main Steam System is nut affected by the TGSCC Degradabon Mechanism due to the absence of hahdes and caustics, per EPRI ; W;ter Chemistry Guidelines ECSCC-1 operating temperature > 150*F, and a a 0 x ECSCC 2 tensile stress is present, and a a a x , I ECSCC 3-1 an outside piptng surface is within I?ve diameters of a probable a a a x leak path le g , valve stems) and is covered with non metallic l insulation that is not in compliance with Reg. Guide 1.30, or l ECSCC-3-2 en outside piping surface is exposed to wetting from chloride o a a x bearing environrrOnts (e g , seawater, brackish water, brine) in conduskm, the ECSCC Degradabon Mechanism is not apphenble to the Main Steam System tiecause it is composed of carbon steet. PWSCC1 piping materialis inconel(Alicy 600), and a x a a PWSCC-2 exposed to primary water at T > 620*F, and a x 0 0 PWSCCS1 the materialis mill-annealed and cold worked, or 0 0 x a PWSCC 52 cold wrked and wided without stress relief a a X o in conduskm, the Main Steam System is not affected by the PWSCC Degradabon Mectianism due to the system is not exposed to pnmary water at T> 620*F and not composed of inconet. MIC-1 operating temperature < 150*F, and a x 0 0 MIC 2 low orIntermittent flow, and a O x a MIC-3 pH < 10, and a a X o MIC-4

presenceAntrusion of organic matertal(e g., raw water system), o a x a or MIC-4 2 water source is not treated whiocides (e p., refueling water tank) o a x 0 in condusion, the Main Steam System na not affected by the MIC Degradabon Mechanism due to the fact that this system is exposed to an operating temperature greater than 150*F, PIT 1 potential exists for Jow flow, and a x 0 0 PIT 4 oxygen or oxid! zing species are present, and x a a a PIT-3 Initiating contaminants (e g., fluoride, chloride) are present a x a a W meets EPRI Water Chemistry Guidelines.

In condusion, the Main Steam System is not affected by the PIT DegradaUon Mechanism due to the fact that this system is not exposed to low flow mndluons or PIT initlahng contaminants, as VY complies with EPRI Water Chemistry Guidelines. CC-1 crevice condmon exists (e g., thermal sleens), and a x 0 0 CC-2 operating temperature > 150*F, and x a o a CC-3 oxygen or oxidizing species are present x a a a in condusion, the Main Steam System is not affected by the CC Degradation Mechanism due to the fact that the only locahon suscepuble to CC is undemeath thermal sleeves at reactor vesset nozz's locations. The weld locanon corresponding to this locabon is the nozzle-to-safe end weld, a B-F weld, exduded from this evaluation. E-C-1 existence of cavitation source (I e., throttling or pressure a y a a reducing valves or orilices) E-C 2 operating temperature < 250*F, and a y a a E-C 3 tiow present > 100 hrs &r, and a a y a E-C-4 velocity > 30 It's, and a a y a E-C-5 (Po PJ / AP < S a a y a in condusion, the Main Steam System is not affected by the EC Degradabon Mectonism due to the absence of a cavitation source and due to the tact that the operating temperature is greater than 250*F, FAC-1 evaluated in accordance with existing plant FAC program x a a a in mnclusion, the Main Steam System is not affected by the FAC Degradauon Mechanism due to the fact that It is a part of VY's FAC program (37].

e e W Assosoment MeM Concluelone Nsk Segynent No. No- Atutbuses so be ConeMermt en a, w m Memarks M *

M M '

Water D X u O Hammer l a

l l l DEGRADATION MECHANISM EVALUATION FOR HPCIIRCIC SYSTEMS Revision: 0 Prepared Ily/Date: Checked By/Date: File No. EPRI-116-301 Page B-5 of B-7

                 .          .                                                                                                                             l Degradation Mechanism Assessment Worksheet                               Conclusions                       Risk Segment No.

No. Attrbutes to be Considered Remarks l '" l ** l *" l ^" nps > 1 bch, and I TASCS-1 X a a a l TASCS 2 pipe segment has a skapo < 45' from horizontal (includes elbow x a a a l of too blo a verticalpipe), and TASCS S1 potential exists for low flow M e pipe section connected to a a y a a M steam. component allowing mixbg of hot and cold fluids, or TASCS 32 potential exists for Joakage flow past a valve (I e., in leakage, a x a a M steam. out. leakage, cross Joakage) allowing inlxing of hot and cold fluids, or TASCS-3-3 potential exists for convection heating in dead +nded pipe a x a a M steam. sections connected to a source of hot fluid, or TASCS-3-4 potential exists for tso phase (steam / water) flow, or a x a a M steam. TASCS-S$ potential exists for turbulent penetration h branch pipe a X a a M steam. connected to headerp4 ping containing hot fluid with high turt>ulent flow, and TASCS-4 calculated orinoasured AT> 50*F, and a a x a TASCS-5 Richardson number > 4.0 a a x a in conclusion, the HPCl/RCIC Systems are not affected by the TASCS Degradation Mechanism due to the tact that both tystems normally contain all steam. TT1-1 operating temperature > 270*l" for stainless steel, or a a a a TT 14 operating temperature > 220*F for carbon steel, and x a a a potential for relatively rapid temperature changes including TTS-1 cold water irVection into hot pipe segment, or o X a a TT.88 hot waterIrdection into coldpipe segment, and a x a a TT 31 l ATl > 200*F for stainless steel, or x a o a TT 3-2 l ATl > 15tl* Flor carbon steel, or a o x a TT 33 l ATI > AT allowable (applicable to both stainless and carbon) o a x a in conclusion, the HPCI/RCIC Systems are not affected by the Thermal Transient (TT) Degradaten Moharism due to the fact that no cold / hot water injection into hot / cold piping occurs (although the operating temperature is greater than 220*F). IGSCC-B-1 evaluated in accordance wIth wxisting plant IGSCC program per a x 0 0 RCICMPCI systems are composed of carbon NRC Generic Letter 88-01 steel. IGSCC-P 1 operating temperature : 200*F, and a a a x WA applies only to PWRs. IGSCC-P-2 susceptible material (carbon content 2 0.035%), and a a a x WA applies ordy to PWRs. IGSCC-P-3 tensIIe stress (bcluding residual stress) is present, and a a O x tbA applies only to PWRs. IGSCC-P-4 oxygen or oxidizing species are present a a a x WA applies only to PWRs. OR IGSCC-P-5 operating temperature < 200*F, the attributes above apply, and a a a x WA applies only to PWRs. IGSCC P-6 initiating contaminants (e g., thiosulfate, fluoride, CIdonde) are a a a x WA applies only to PWRs. also required to be present in mnclusion, the HPC1/RCIC Systems are not affected by the IGSCC Degradation Mechanism due to the fact that the piping systems are composed of carbon steel, a material that is not susceptible to IGSCC. TGSCC1 operating tempaature > 150*F, and x a a a TGSCC-2 tenslie stress (including residual stress) is present, and x a a a TGSCC-51 halides (e.g., fluoride, cIdonde) are present, or a x a a Impurities are controIIed per EPRI Water Chemistry Guidelines. TGSCC-3-2 caustic (NaOH)ls present, and a x 0 a TGSCC 4 oxygen or oxidizing species are present (only required to be x 0 0 a present M coryunction whalides, not required w/ caustic) in conclusion, the RCICMPCI Systems are not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per EPRI Water Chemistry Guidelines.

Degradotion Mechanism Assessment Worksheet Risk Segment No. l l Conclusions Remarks l No. l Attributes to be Considered

l ** l
l
ECSCC1 operating ternporature > 150*F, and a a a x ECSCC 2 tenslie stress is present, and a a o x ECSCC4.I en outsido piping surface is within fin diameters of a probable a a a x leak path (e p., valve stems) and is conred with non4notalloc Insulatoon that is not in compliance with Reg Guide 1.36, or ECSCC-3-2 en outsido piping surface is exposed to wetting from chionde o a a x beanng environments (e g., seawater, brackish water, brine) in conclusion, the RCIC/HPCI Systems are not affected by the ECSCC Degradation Mechanism due to the fact that these systems are composed of carbon steel.

PWSCC-1 piping materialis Inconel(Alloy 600), and a x 0 0 PWSCC-2 exposed to primary water at T> 620*F, and a x a a PWSCC4-1 the snatorialis mill-annealed and cold worked, or a a x a PWSCC42 cold worked and welded without stress relief a a x 0 in (x)nclus60n, the RCIC/HPCI Systems are not affected by the PWSCC Degradation Medianism due to the fact that this system is not exposed to primary water with a temperature >620*F and does not contain inconol. MIC 1 operating temperature < 150*F, and a x 0 0 MIC-8 low orIntermittent flow, and a a y a MIC4 pH < 10, and a O x a MIC 41 presenceAntrusion of organic material (e g., raw water system), a a y a or MIC-4-2 water source is not treated w/ biocides (e.g., refueling water tank) a a y a in condusion, the RCICMPCI Systems are not affected by the MIC Degradaten Mechanism due to the tact that these systems are exposed to an operating temperature greater than 150*F, PIT.1 potentialexists forlow flow, and a y o a PIT 2 oxnen or oxidizing speclos are present, and x a o a PIT-3 Initiating contaminants (e p., tivorida, chloride) are present a y a a Initiating contaminants contm!Ied per EPRI Water Chemistry Guidelines. In condusion, the RCICIHPCI Systems are not affected by the PIT Degradation Mechanism due to the fact that these system are not subjected to low flow conditions and they are not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines. CC-1 crevice condition exists (e.g., thermal sleeves), and a x 0 0 CC4 operating temperature > 150*F, and x 0 0 0 CC4 oxnen or oxidizing species are present a a a a in condusion, the RCICIHPCt Systems are not affected by the CC Degradation Mechanism due to the fact that the only location susceptible to CC la undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to safe end weld, a D-F weld, excluded from this ev31uabon. E-C-1 existerne of cavitation source (i.e., throttling orpressure a y a a reducing valvos or orifices) E-C-8 operating temperatum < 250*F, and a x a a E-C4 flow present > 100 hrs % and a a x 0 E-C-4 nlocity > 30 Itts, and a a x a E-C-5 (Pn - P)/AP < $ a a x a in condusion, the RCIC/HPCI Systems are not affected by the EC Degradation Mechanism due to the fact that no cavitation source exists in these systems and the operabng temperature is greater than 250*F, FAC-1 evaluated in accortlance with existing plant FAC program x a a a RCICMPCIare a part ofMSO a system includedin VYs FAC program (37) In conclusion, the RCICMPCI Systems are not affected by the FAC Degradaten Mechanism due to the fact that these systems are induded in the FAC program.

Degradation Mechanism Assessment Worksheet Conclusions Risk Segment No. No. l Attributes to be Considered

                                                      *l**l**l**       Remarks Water                                                a  y    9    a Hammer l

l l l l l 1

APPENDIX C DEGRADATION MECHANISM EVALUATION FOR MAIN FEEDWATER SYSTEM t Revision: 0 Prepared By/Date: - Checked By/Date: File No. EPRI-116-301 Page C-1 of C-3

e , Degradation Mechanism Assessment Worksheet Conclusions Risk Segment No. No. Attributes to be Considered * ** * *" Remarks l TASCS-1 nps > 1 inch, and x a o a TASCS-2 pipe segment has a slope < 45* from horizontal (includes elbow x a a a of toe into a verticalpipe), and TASCS-3-1 potential exists for low flow in a pipe section connected to a x a o a Cold RCIC into hot Isola >d FW(applicable to component allowing mixing of hot and cold Dukts, or horizontalsegment of L no B (Class 1 to Class 2 boundary). TASCS-3-2 potential exists for leakage flow past a valve (I.e , in-leakage, a x a a out-leakage, cross-leakage) allowing mixing of hot and cold fluids, or TASCS 3-3 potential exists for convecbon hosting in dead ended pipe a x a a sections connected to a sotoce of hot fluid, or TASCS 34 potential exists for two phate (steam / water) flow, or O x a a TASCS-3-5 potential exists for turbulent penetrabon in branch pipe x a a a connected to header piping containing hot fluid with high turbulent flow, and 7ASCS-4 calculsted or measured AT > $0*F, and x a o a TASCS-5 Richardson number > 4.0 x a o a in condusion, horizontal segments of Line B of the Main Feedwater System are affected by the TASCS Degradation Mechanism due to the flow of RCIC Into these Loops. TT 11 operating temperature > 270*F for stainless steel, or a a a a 7T 18 operuttg temperature > 220*F for carbon steel, and x a a a potential for relatively rapid temperature changes including TT 21 cold water Irfection into hot pipe segment, or o x a a TT 2 8 hot water Irfection into cold pope segment, and x a o a Hot Reactor Water backflow into Nozzles (applicable to all Loops). l TT-3-1 l ATI > 200*F for stainless steel, or a a a a TT 3-8 l ATl > 150*F for carbon steel, or x a o a TT 3-3 l ATI > AT allowable (applicable to both stainless and carbon) o a x a Both loops are atfected by TT in close proxJmity to the reactor vessel (horizontal sectsons to first elbow) due to hot reactor water backflow into co4d FW piping. IGSCC-B-1 eva'osted in accordance with existing plant IGSCC program per o x a a not part of 88-01 program sInce carbon steel NRC Generic Letter 88-01 IGSCC-P-1 opemting ternperature > 200*F, and a o a x N/A applies only to PWRs. IGSCC-P-2 susceptible material (carbon content a 0.035%), and O O a x N/A applies only to PWRs. IGSCC-P-3 tensile stress (including msidual stress) is present, and a a o x NrA applies only to PWRs. IGSCC-P-4 oxnen or oxidizing species are present a a a x N/A applies only to PWRs. OR IGSCC-F-5 operating temperature < 200*F, the attributes above apply, ano o a o x N/A applies only to PWRs. IGSCC-P 6 initiating contaminants (e g., thiosulfate, Ifuoride, chloride) are a a o x N/A applies only to PWRs. also required to be present in condusion, the Main Feedwater System is not affected by the IGSCC Degradation Mechanism due to the fact that the piping is mrnposeo of carbon steel, a material that is not susceptible to IGSCC. TGSCC.1 oporating temperature > 150*F, and x a a a TGSCC-2 tenslie stress (including residual stmss) is present, and x a a a TGSCC-3-1 hahdes (e g., fluonde, chi 6 tide) ers present, or o x a a Impunties are controlledper EPRI TGSCC-3-2 caustic (NaOH)is present, and a x a a water chemistry guidelines. TGSCC-4 oxygen or oxidizing species are present (only mquired to be x a a a present in corfunction w) halides, not requimd w/taustic) in conclusion, the Main Feedwater System is not affe :ted by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per EPRI Water Chemistry Guidelines.

                                                                                                                                              ,   e Degradation Mechanism Assessment Worksheet                                      Conclucions                  Risk segenent No.

Attributes to be Considered Remarks No. l '" l ** ** l M ECSCC1 operstmg temgaature > tbo*F, and x a a a ECSCC-2 tensIIe stress is present, and x a o a ECSCC-3-1 an outside piping surface is within frve diameters of a prot >able o a a x leak path (e p , Valve stems) and is covered with non4 nota!bc insulation that is not in compItance with Reg Guide 1.36, of ECSCC-3 2 an outsIde piping surface is exposed to wetting from chloride a O x 0 bearing environments (e g , seawater, brackish water, brine) In condusion, the Main Feedwater System is not affected by the ECSCC Degradation Mechanism due to the fact the the system is composed of carbon steel. PWSCC 1 piping matenalis inconel(Alloy 600), and a x 0 0 PWSCC 2 exposed to primary water at T > 620*F, and a x a a PWSCC 31 the materialis mill-annenled and cold worked, or a a x a PWSCC 3-2 cold worked and wided without stress relief a a x a in conduson, the Main Feedwater System is not affected by the PWSCC Degradation Mechanism due to the fact that this system is not exposed to pdmary water at T> 620*F and mntains no inconet MIC 1 operating temperature < 150*F, and a x a a MIC-8 low orintermittent tiow, and n a x a Rornote event. AtlC 3 pH< 10, and a O x 0 MIC-41 presenceAntrusion of organic material (e g , raw water system), a a x a of MIC-4-2 water source is not treated w,t>iocides (e g., refueling water tank) 0 a x a in conclusion, the Main f eedwater System is not affected by the MIC Degradabon Mechanism due to the fact that this system is exposed to an operCting temperature greater than 150*F. PIT 1 potentialexists forlow flow, and a x a a PIT-3 oxygen or oxidizing species are present, and x a a a PIT 3 initiating contaminants (e p., Ituoride, chloride) are present o x a a in conclusion, the Main Feedwater System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY mmplies with EPRI Water Chemistry Guidelines. CC 1 crevice condition exists (e.g., thermal sleeves), and a x 0 a CC8 operating temperature > f 50*F, and x 0 a a CC-3 oxygen or oxidizing species are present x 0 o o in conclusion, the Main Feedwater System is not affectxi by the CC Degradation Medanism due to the fact that the only location susceptible to CC b undemeath thermal sleeves at reactor vessel nozzle locahons. The weld locaboa corresponding to this location is the nozzle-to-safe end weld, a B. F weld, exduded from this evaluation. E-C 1 existence of cavitation source (I e., throttling or pressure a a y a reducing valves or ori0ces) E-C-8 operating temperature < 250*F, and a x a a E-C-3 tiow precent > 100 brsyr, and a a x a E-C-4 velocity > 30 ft/s, and a a x a ,,F-C-5 (Pg P,) / AP < $ a a y a in condusion, the Main Feedwater System is not affected by the EC Degradation Mechanism due to the fact that the operating temperature is greater than 250*F. FAC-1 ovaluated in accordance with existing plant FAC pros 'um x a a a In condusion, the nine locations (FW19-F4, FW18-F3A, FW21-F1, FW20-F38, FW20-F1, FW20-F18, FW19-F38, FW19-F3C and FW18-F4) within the Main Feedwater System can be considered suscepbble to the FAC Degradation Mechanism due to the fact that these locations are routinely monitored as a result of the implementation of VY's FAC Program.

Degradeelen Nochen'tm Aseeeement Workeheet Concluelone Red $ w t % h ANributee to be ConeJderest ta == 3 ase m mg, EM m Weier U X U U Hemmer l t-I

e 1 APPENDIX D DEGRADATION MECHANISM EVALUATION FOR RESIDUAL HEAT REMOVAL SYSTEM 24-RHR 31 (Discharge) i 24-RHR-30 (Discharge) 20-RHR-32 (Suction) C ',% Revision: 0 Prepared By/Date: . Checked By/Date: File No. EPRI-116-301 Page D-1 of D-13

DEGRADATION MECHANISM EVALUATION FOR 24-RHR 31 (DISCHARGE) i Revision: 0 Prepared By/Date: Checked Hy/Date: File No. EPkI-116-301 Page D-2 of D-13 l l

Degradation hiechazism Assessment Worksheet ConchrJons Risk segmentNo. No. Attributes to be Considered * ** ** "^ Remarks TASCS 1 nps > 1 Mch, and x a a a TASCS 2 pipe segment has a skpe < 45' from honzontal(hcludes elbow x a a a or tee into a vertscalpipe), and TASCSS t potential exists for low flow h a pipe section connected to e a x a a component allowing mixing of hot and cold flulds, or TASCS42 potential exists for Joakage flow past a valve (i.e., in-leakage, a x 0 0 o& leakage, crosskakage) alloMng mixing of hot and cold fluids, or TASCS&3 potential exists for convection heating in dead <nded pipe O x 0 a sections connected to a source of hot fluid, or TASCS&4 potential exists for tse phase (steam / water) flow, or a x a a TASCS&S potential exists for turbulent penetraUon M branch pipe a x a a connected to header piping containing hot fluid with high turbulent flow, and TASCS-4 calculated or measured AT > $0*F, and O O x 0 TASCS 5 Richardson number > 4.0 g olx a in conclusion, Lines 24-RHR-31 and Unes 24-RHR 29 (Discharge) of the RHR system are unaffected by the TASCS Dogf adation Medanism due to tkD absence of stratification, convective heating. two phase flow, etc. TT 11 operating temperature > 270*F for slainless steel, or x 0 a a 24RHR41 TT 12 operating temperature > 220*F for carbon steel, and x a a a 24RHR-29 potential for relatively rapid temperature changes hcluding TT 2.t cold weter Iryoction Into hot pipe segment, or X 0 0 0 24-RHR 31 (Doubleshock) TT 2 2 hot wateriryection into coldpipe segment, and X o a 0 24RHR-28; 24-RHR 31 (Doubleshock) TT 31 l ATl > 200*F for stainless steel, or x a a a Double shock of coldhot water M 24 RHR 31 TT 3-2 l ATl > 150*F for carbon steel, or a a o a TT4-3 l ATl > AT allowetdo (applicable to both stainless and carbon) O a a a in conclusion, Line 24-RHR 31 is affected by the Thermal Transient (TT) Degradabon Mechanism due to the tact that this hne expertences a

double-shock
of hot and then cold water injected into cold.h A piping hne during shutdown cooling, resulting in a AT greater than 200*F, in addition. Line 24 RHR-29 experiences hot water irSection into a normally cold line during shutdown cooling.

IGSCC-B-1 evaluated in accortlance with existing plant IGSCC program per x o x a All welds classined as IGSCC Category A 16r NRC Generic Letter 88-01 24 RHR-31,14C lbf 24-RHR 29 (CS) IGSCC-P 1 operating temperature > 200*F, and a a a x WA applies only to PWRs. IGSCC-P-2 susceptible material (carton content t 0.035%), and a a a x WA applies ordy to PWRs. IGSCC P4 tensIIe stress (including residual stress) is present, and o a 0 x WA applies only to PWRs. IGSCC-P-4 cxnen or oxktizing species are present a o a x WA applies only to Pnns. OR IGSCC-P-5 operating temperature < 200*F, the attributes abcVe apply, and a o o x WA applies only to PnRs. IGSCC-P-6 initiating contaminants (e g., thiosulfate, fluoride, chloride) are a o a x WA applies only to PWRs, also required to be present in condusion, unes 24-RHR-31 & 24-RHR 29 (dischar;o) of the RHR System are not affected by the IGSCC Degradation Mechanism due to the fact that all welds in Line 24-RHR-31 (SS) are dassified as 13 SCC L,ategory A per the NRC Generic Letter 88-01, (L'ne 24-RHR-29 is composed of carbon steet, material that is not susceptible to IGSCC.) TGSCC-1 operating temperature > 150*F, and x a a a TGSCC-2 tensile stress (including residual stress)is present, and x a o a TGSCC 3-1 halides (e.g., fluoride, chloride) are present, or O x a a Impurities are controlled por EPRI Water Chemistry Guidelines. TGSCC-3-2 caustic (NaOH)is present, and a x 0 0 TGSCC-4 oxygen or oxktizing species are present (only required to be x a a a present in corgunction wit 1alides, not required WAcaustic)

Degradation Mech 1nism Asserment Worksheet Conclusions Risk segment No. No. Attributes to be Conskrered * *

M Remarks g g g g _ . _ _ . _ _ . _ _ . . . _ . . _ . - _

ECSCC1 c\perating temperature > t50*F and x a a a ECSCC 2 tensile stress is present, and X a a a ECSCC 3-1 an outside piping surface is within fin diameters of a probable a x a a Wcomphes with Reg Guide 1.36 Joak path (e g , valve stems) and is covered with non metalkc insulaticn that is not in comphance with Reg. Guide 1.36, or ECSCC-3 2 an outside piping surface is exposed to wetting from chloride o x 0 a bearing environments (e g,, seawater, brackish water, brine) in mndus60n, the Core Spray System is not affected by the ECSCC Degradabon Mechanism due to the fact that the system is insulated with non. rnetalho insulation per Reg Guide 1.36. PWSCC1 pfping materialis Inconel(Aby 600), and a x a a l PWSCC-2 exposed to primary water at T > 620*F, and a x a a PWSCC 3-1 the materialis mill-annealed and cold worked. s a o x a PWSCC 3-2 cold worked and welded without stress relief a o x a in mndusion, the Core Spray S3 tem is not affected by the PWSCC Degradabon Mechanism due to the fact that this system is not exposed to primary water at T> 620*F and contains no inconel. MIC 1 operating temperature < 150*F, and x a a a Portions away from RPV, MIC-2 tow orintermittent flow, and X o o a MIC-3 pH < 10, and X a a a MIC-41 presencellntrusion of organic material (e.g., raw water system), a x a a Impurities are controlledperEPRI water or chemistry guidelines. MIC-4-2 water source is not treated w/blocidos (e g., refueling water tank) a ,v

a a in condus6cn, the Core Spray System is not affected by the MIC Degradabon Mechanism d've to the ' act that this system is not exposed to organic malertals and/or is treated with blocides per the EPRI Water Chemistry Guidelines. PIT 1 poteMisiexists forlow flow, and x a O a PIT 2 oxygen or oxidizing species are present, and x a o a PIT 3 initiating contaminants (e.g., fluoride, chloride) are present a x a a Initiating contaminants are controlled per EPRI water chemistry guidelines. In condusion, the Core Spray System is not affected by the PIT D* gradation Mechanist.3 due to the fact that this system is not exposed to PIT initiating mntaminants, as W complies with EPRI Water Chemistry Guidelines. CC 1 crevice condition exists (o g., thermal sleens), and a x a a CC-2 operating temperature > 150*F, and X a a a CC-3 oxygen or oxidizing species are present a 0 x a in condusion, the Core Spray System la not affected by the CC Degradation Mechanism due to th6 fact that the only location susceptible to CC ls undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location ts the nozzle tcmfe end weld, a B-F weld, cxduded from this evaluabon. E-C-1 existence of cavitation source (i.e., throttling orpressure a x a a reducing valves orortfoces) E C-2 operating temperature < 250*F, and a y a a E-C-3 tiow present > 100 hrshr, and a a X a E-C-4 velocity > 30 ft s, and a a x 0 E C-5 (Po P)/sP < $ a a X a in condusion, the Core Spray System is not affected by the EC Degradation Mechanism due to the tact that no cavitabon source exists in the system cnd the operahng temperature is greater than 250*F. FAC-1 evaluatedin accordance with existing plant FAC program a x a a The Class 1 portion is SS and not expected to be part of the FAC Program. In condusion, the Core Spray System is not affected by the FAC Degradation Mechanism due to the fact that the system is not induded in VY's FAC progrcm (i.e., the system is composed of stainless steel).

4 i Degredation heechenlem Assessment Warhoheet Conclusions Mieh Segment No. No. Attritwies to be Considered ** ** *

Romerks Wafer O X 0 0 Hamnnr "i

q. .

1 i APPENDIX E I l l DEGRADATION MECHANISM EVALUATION L

FOR

[r ? CORE SPRAY SYSTEM i Revision: 0 Prepared By/Date: - Checked By/Date: File No. EPRl-116-301 Page E-1 of E-4 ;

.m

n a Degradation Mechanism Assessment Worksheet Conclusions Cisk segment No. No. Attributes to be Considered Remarks l '" l ** l *** l **^ , TASCS 1 nps > 1 inch, and x 0 0 0 TASCS-2 pipe segment has a slope < 45* from horizontal (includes elbow x a a a or tee into a verticalpipe), and TASCS-3-1 potential exists for low flow in a pipe section connected to a a x a a Stagnant (hot RPV). component allowing mixing of hot and cold fluids, or TASCS-3-2 potenual exists for loakage now past a valm (i e., M-leakage, a x 0 a out-leakage, cross leakage) allowing mixing of hot and cold Ruids,or TASCS-3-3 potential exists for convection heating in dead-ended pipe x 0 a a Convective heating for segment near RPV. sections connected to a source of hot huid, of TASCS-3-4 potential exists for two phase (steam / water) flow, or a x 0 0 TASCS-3-5 potential exists for turbulent panotrabon in branch pipe a x a a connected to header piping containing hot Ruid with high turbulent flow, and TASCS-4 calculated or measumd AT> $0*F, and X o a a TASCS-5 Richardson number > 4 0 x 0 0 o in condusion, the horizontal segments of Core Spray System (Loops A and D) nec.t the RPV are affected by the TASCS Degradsbon Mechaniwn due to tx)nvective heahng from the RPV. TT 11 operating temperature > 270*F for stainless steel, or x a o a TT 12 operating temperature > 220*F for carbon steel, and a a a a potential for rotatively rapid temperature changes including TT 21 cold water lifection into hot pipe segment. or a x a a TT-2-2 hot wator tryection into cold pipe segment, and a x a a TT 31 l ATl > 200*F for stainless steel, or o a x 0 TT 3-2 l ATl > 150*F for carbon steel, or a O x a TT 3 3 l ATl > AT allowable (applicable to both stainie.s and carbon) o O x a in condusion, the Core Spray System is not affected by the Thermal Transient (TT) Degradabon Mechanism due to the fact that no oold/ hot water f' injection into hot / cold piping occurs (although the operatang temperature is greater than 270*F). ( Ma}orityof welds (exceptsafe-endtopiping Y IGSCC-B-1 evaluated in accordance with existing plant IGSCC program per o x a a NRC Generic Letter 08-01 weld) classl6ed as IGSCC Category A. IGSCC-P-1 operating temperoture > 200*F, and a a o x N/A applies only to PWRs. IGSCC-P-2 susceptible material (carbon content t 0.035%), and a a o x N/A applies only to PHRs. IGSCC-P 3 tensile stress (including residual stress) is present, and a a a x IVA applies only to PWRs. IGSCC-P-4 oxygen or oxidizing species are present a a a x N/A applies only to PARS. OR IGSCC P-5 operating temperature < 200*F, the attributes above apply, and o a a x N/A applies only to PWRs. IGSCC-P-6 initiating contaminants (e g., thiosulfate, Ruonde, ch}oride) are o a o x N/A applies only to PWRs. also required to be present in condusion, the Core Spray System is not affected by the IGSCC Degradation Mechanism due to the fact that all welds are dassifed as IGSCC Category A per the NRC Generic Letter 88-01, The safe-end to piping wekt is affected by the IGSCC Degradation Mechanism but is dassified as B-F weld, outside the scope of this evaluation. TGSCC-1 operating tornporature > 150*F, and x a o a TGSCC-2 tenslie stess (including residual stress) is present, and x a a a TGSCC-3-1 halides (e.g., nuoride, chloride) are present, or a x a a Impurities are controlledperEPRI TGSCC-3-2 caustic (NaOH)is present. and a x a a water chemistry guidolines. TGSCC-4 oxygen or oxidizing species are present (only required to be x a o a present in corgunction wthalides, not required wk.austic) in conclusion, the Core Spray System is not affected by the TGSCC Degradation Mechanism due to the absenca Ut halides and caustics, per EPRI W; tor Chemistry Guidelines.

e e ! r , Degradation Mechanism Assessment Worksheet Conclusions Risk Segment No,

                                                                                                  * * * "                    Remarks No.                              Attributes to be Considered

l *"

ECSCC-1 operating temperature > 150*F, and X a o a CSCC-2 tensile stress is present, and x a a a ECSCC-3-1 an outside piping surface Is Mthin five diameters of a probable a x a a VY cornphes with Reg Guide 1.36 leak path (e g., valve stems) and is covered with non-metallic insulatiort that is not in compliance with Reg. Guide 1.36, or ECSCC-3-2 en outside piping surface is exposed to wetting from chionde a x a a beadng environments (e g., seawater, brackish water, bnne) in condus6on, the Core Spray System is not affected by the ECSCC Degradatson Mechanism due to the fact that the system 6s insulated with non. metaliic insulation per Reg Guide 1.36. PWSCC1 piping materialis inconel(Alloy 600), and a X a a PWSnC-2 exposed to primary water at T > 620*F, and a x a a PWSL C-31 the materialis mill-annealed and cold worked, or a O x a PWSC C-3-2 cold worked and welded without stress relief a a X a in conclusion, the Core Spray System is not affected by the PWSCC Degradabon Mechanism due to the fact tnat this system ts not exposed to prinrry water at T> 620*F and mntains no inconel. MIC 1 operating femperature < 150*F, and y a a a Portions away from RPV, MIC-2 Jow orIntermittent flow, and x a o a MIC-3 pH < 10, and x a a a MIC41 presenceAntrusion of organic matenal(e g., raw water system), a x a a Impunties are controlledper EPRI wolor or chemistry guidelines. MIC-4 2 water source is not treated w/blocidos (e g., refueling wrter tank) a x a a in condusion, the Core Spray System ts not affected by the MIC Degradation Mechanism due to the "act that this system is not exposed to organic rrit; rills and/or is treated with bioddes per the EPRI Water Chemistry Guidelines. PIT-1 potentialexists forlow flow, and x a a a PIT-2 oxygen or oxidizing species are present, and x a o a PIT 3 initiating contaminants (e g., fluodde, chloride) are present a x a a Initiating contaminants are controlledper EPRI water chemistry guidelines. In condusion, the Core Spray System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT initiating contaminants, as VY complies with EPRI Water Chemistry Guidelines, CC 1 crevice condition exists (e 0., therma: sleeves), and a x a a CC-2 operating temperature > 150*F, and X a a a CC-3 oxygen or oxidizing species are present a a x a in conclusion, the Core Spray System is not affected by the CC Degradation Mechanism due to the fact that the only location susceptible to CC is undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle to-safe end weld, a B-F weld, cxduded from this evaluation. E41 existence of cavitation source (i e., throttling orpressure O x a a reducing valves or orifices) E42 operating temperature < 250*F, and a y a a E-C-3 flow present > 100 hr@r, and a a x a E-C-4 velocity > 30 tVs, and a a x a E-C-5 (P, . P,) /,$P < 5 a o x a in condusion, the Core Spray System is not affected by the EC Degradation Mechanism due to the fact that no cavitation source exists in the system and the operating temperature is greater than 250*F, FAC 1 evaluated in accordance with existing plant FAC program a x a a The Class 1 portion is SS and not expected to be part of the FAC Program. In condusion, the Core Spray System is not atfected by the FAC Degradation Mechanism due to the fact that the system is not induded in VY's FAC progrrm (i.e., the system is composed of stainless steel).

e . Degradetion Mechanism Assessment Worksheet Conclusions Rask segment No.

                                                     '"  **           Remarks No.                    Attributes to be Considered

l ***

Water D X D D Hammer i I i I

0 0 APPENDIX F i l DEGRADATION MECHANISM EVALUATION FOR STANDBY LIQUID CONTROL SYSTEM , ( Revision: 0 Prepared By/Date: - Checked By/Date: File No. EPRI-116-301 Page F-1 of F-4

e .

                                                                                                                                                                                      . s Degradation Mechanism Assessment Worksheet                               Conclusions                           Risk Segment No.

Attributes to be Considered Remarks No. l

l ** l "c l ** _-

TASCS-1 nps > 1 inch, and x a a a TASCS-2 pipe segment has a slope < 45' from honzontal(includes ottow x 0 0 a or fee into a verticalpipe), and TASCS S1 potential exists for low now in a pipe sectoon connected to a a x a a component allowing mixing of hot and cold fluids, or TASCS-32 potential exists for leakage flow past a valve (I e., in-leakage, a x a a out-leakage, cross-leakage) allowing mixing of hot and cold fluids, or TASCS-S3 potential exists for convection heating in dead 4nded pipe x a a a First tw segments away from RPV only, sections connected to a source of hot fluid, or TASCS-3-4 potential exists for two phase (steam / water) now, or o x 0 0 TASCS-S$ potential exists for turbulent penetration in branch pipe o x a a connected to header piping containing hot fluid with high turbulent flow, and TASCS-4 calculated or measured AT > 50*F, ar'd x a a a First two segments away from RPV only. TASCS-5 Richardson number > 4.0 x a a a Stagnant. In conclusion, the first two segments of the Standby Liquid Control System adjacent to the reactor pressure vessel are affected by the TASCS Degradabon Mechanism due to convection heating. TT 11 operating temperature > 270*F for stainless steel, or x a o a TT 12 operating temperature > 220*F for carbon steel, and o a a a potential for relatively rapid temperature changes including TT-2-1 cold waterirgection into hot pipe segment, or a x a a l bot water Irfection into cold pipe segment, and a x a a TT 2-2 TT-3-1 l ATl > 200*F for stainless steet, or o a x a TT-3-2 l ATl > 150*F for carbon steel, or o a X a TT-3-3 l ATl > AT al!owable (applicable to both stainless and carbon) a o x 0 in condusion, the Standby Uquid Control System is not affected by the Thermal Transient (TT) Degradabon Mechanism due to the fact that no cold / hot water injection into hot / cold piping occurs (although the operating temperatute is greater th n 270*F). IGSCC-B 1 evaluated in accordance with existing plant IGSCC program per a x a a Not covered by Generic Letter but susceptible NRC Generic Letter 88 01 to IGSCC lor portions with temperature greater than 200*F. IGSCC-P-1 operating temperature > 200*F, and a a o x N'A applies only to PWRs. IGSCC-P 2 susceptible material (carbon content ;n 0 035%), and a o a x N/A applies only to PWRs. IGSCC-P-3 tenslie stress (including residual stress) is present, and a a a x N/A applies only to PWRs. IGSCC-P-4 cxyyen or oxidizing species are present aayx N/A applies only to PnRs. OR IGSCC-P-5 operating temperature < 200*F, the attributes above apply, and a a o x N/A applies only to PWRs. IGSCC-P-6 Ntiating contaminants (e 0., thiosulfate, fluoride, chloride) are a a o x N/A applies only to PWRs. also required to be present in condusion, the Standby Uquid Control System is affected by the IGSCC Degradation Mechanism due to the fact it is composed of suscepuble material. TGSCC-1 operating temperature > 150*F, and a x a a TGSCC-2 tenstre stress (including residual stress) is present, and x a a a TGSCC-51 halides le o., fluoride, chloride) are present, or a x 0 a Impurities are controlledper EPRI Water Chemistry Guidelines. TGSCC-3-2 caustic (NaOH)is present, and a x a a TGSCC-4 oxpyen or oxidizing specoes are present (only required to be x a a a present in conjunction wthahdes, not required w/ caustic) in conclusion, the Standby Liquid Control System is not affected by the TGSCC Degradation Mechanism due to the absence of halides and caustics, per EPRI Water Chemistry Guidelines. l 1

                .            e s .        ,

Degradation Mechanism A:sessment Worksheet Conclusions RI:k Segment No. No. l Attributes to be Considered Ml*l*

Remarks ECSCC-1 operating tsmperature > 150*F and X a a a ECSCC-2 tensile stress is present, and a a a a l ECSCC-3-1 an outwde piping surface is within hve diameters of a probable a y a a VY comphes with Reg Guide 1.36 leak path (e g., valn> stems) and is covered with non. metallic

{ insulation that is not in compliance with Reg. Guide 1.36, or

  ,l ECbCC-3-2          an outsido piping surface is exposed to wetting from chloride                                            a    x   a a l                    bearing environments (0,0,, seawatnt, brackish water, brine)

In mndusion, H.;, Standby Liquid Control System is not affected by the ECSCC Degradabon Mechan sm due to the tact tnat the system 1* insulated with non-metallic insulation per Reg Guide 1.36. PWSCC-1 piping trmlertalis inconel(Allcf 600), and a X a a exposed to primary water at T > 620*F, and a X a a f PWSCC-2 PWSCC-3-1 the materialis mIII-annealed and cold worked, or a a x a PWSCC-3-2 f cold worked and welded without stmss relief a o x 0

'~

in conclusion, the Standby Liquid Control System as not affected by the PWSCC Degradation Mechanism due to the fact that this system is * , txposed to primary watm at T) 620*F and contains no inconel. - MIC-1 operating tempemture < 150*F, and X a a a ktIC-2 low orintermittent flow, and x a a a MIC-3 pH < 10, and x a a a MIC-4-1 pmsonceAntrusion of organic matettal(e g., raw water system), a x a a Free of microbes because reactor wateris controlledperEPRI Water Chemistry l l or Guidelines. MIC-4-2 l water source is not tmated wklocides (e.g., refueling water tank) O X a a in conclusion, the Stanca y l lquid Control Systen e rat attected by the MIC Degradauon Mechanism ese to the tact that this system is not exposed to organic materials and/or is treated with blocidemr the EPRI Water Chemistry Guidelines. PIT-1 potentialex%ts ibtlow flow, and x a a a t'IT-2 oxygen oroxidizing species are pmsent, and x a a a PITS initiating contaminanN (e.g., fluorido, chloride) are present a x a a Frue ofinitiating contaminants because reactor wateris controlled per EPRI Water Chemistry Guidelines. In conclusion, the Standby Liquid Control System is not affected by the PIT Degradation Mechanism due to the fact that this system is not exposed to PIT Initiating mntaminants, as VY complies with EPRI Water Chemistry Guidelines. CC-1 crevice cor.dition exists (e.g., thermal sleeves), and x a a a SLC system is composed of numerous socket welds. CC-2 operating temperature > 150*F, and x a a a CC-3 oxnen oroxidizing species am pmsent x a a a in conclusion, the Standby Liquid Control System is affected by the CC Degradation Mechanism due to the fact that the only location susceptible to CC b undemeath thermal sleeves at reactor vessel nozzle locations. The weld location corresponding to this location is the nozzle-to safe end weld, a B-F weid, exduded from this evaluation. E-C-1 existance of cavitation source (i.e., throttling or pressure teducing valves or ori&ces) ln x a a E-C-2 operating ternperature < MF, and a x a a E-C-3 flow present > 100 hrsh, and a a x a E-C 4 ve och, 2 30 ft/s. and a y a a

~ T.-5 (Pg - P,) / AP < 5 r.. a l C' l x a _

          #nclusion, the Standby Liquid Control System is not affected by the EC Degradation kschanism due to m tact that no cavitatior, source exists in the system and the operating temperature is greater than 250*F.

FAC-1 evaluatedin accordance with existing plant FAC program a y a a l

s

Degradation Mechanism A:serzment Worksheet Conclusions Risk Segment No.

No. Attributes to be Considered " '" Remarks l "c l ** in mndusion, the Standby Liquid Control Lg em is not affected by the FAC Degradation Mechanism due to the fact that it IS Composed of stainless steel and not a part of VY's FAC program. Wat:r a y a a Ham,nor '4

r ... ,

                                                                                                       'l 1

APPENDIX G DEGRADATION MECHANISM EVALUATION FOR REACTOR WATER CLEAN-UP SYSTEM Revision: O Prepared By/Date: Checked By/Date: File No. EPRI-116-301 Page G-1 of G-1 l

e ,+ e s e Degrs& tion Mechanism Assessment Worksheet Conclusions Risk Segment No. No. Attributes to be Considered Remarks l *l*l*l* TASCS-1 nps > 1 Mch, and x 0 a a TASCS-2 pipe segment has a slope < 45* from bodzontal(sncludes er bow x a a a or tee into a verticalpipe), and TASCS-3-1 potential exists forlow flow is a pipe section connected to a a x a a componont allowing mixing of hot and cold fluids, or TASCS-3-2 potential exists for leakage flow past a valve (I e., in-leakage, O x 0 a out4eakage, crossdeakage) allowing mixing of hot and cold fluids, or TASCS 3-3 potential exists for convection heating in deadended pipe O x a a sections connected to a source of hot fluid, or TASCS-3-4 potential exists for two phase (steam / water) flow, or a y a a TASCS-3 -5 potential exists for turbulent penetration in branch pipe O x a a connected to hesder piping containing hot fluid wrth high turbulont flow, and TASCS-4 calculated or measured AT > 50*F, and a a X o TASCS-5 Richardson number > 4.0 a o y a in condusion, the RWCU System is not affected by the TASCS Degradation Mechanism dua to the tact that no mixing of hot / cold fluids, leakage or two phase flow, etc., can occur. TT-11 operating temperature > 270*F for staintess steel, or x c'a a TT-1-2 operating temperature > 220*F for carbon steel, and x a a a potential for relatively rapid temperature changes including TT-21 cold waterIryoction into hot pipe segment, or O x a a TT-2-2 hot waterirgection into cold pipe segment, and a x 0 a TT 31 lsTl > 200*F for stairNIess steel, or a a x a 1T-3-2 l ATl > 150*F for carbon steel, or a a X 0 TT-3-3 l ATl > ATallowable (applicable to both stainless and carbon) a a X o in conclusion, the RWCU System is affected by the Thermal Transient (TT) Degradation Mechanism due to the tact no told / hot water Mjection occurs into a hot / cold piping. IGSCC-B-1 evaluatedin accordance with existing plant IGSCC program per x a a o all welds classified as IGSCC Category A NRC Generic Letter 68-01 ICSCC P-1 operating temperature > 200*F, and a a o x WA applies only to PWRs. IGSCC-P-2 susceptible material (carbon content: 0.035%), and a a a x WA applies only to PWRs. IGSCC-P4 tensile stress (including residual stresa) is present, and a o a x WA appliss only to PWRs. IGSCC-P-4 oxygen or oxidizing species are pmsent a a O y WA app'ies only to PWRs. OR IGSCC-P-5 operating temperature < 200*F, the attnbutes above coply, and a o a x WA applies only to PWRs. IGSCC-P-6 initiating contaminants (e.g., thiosulfate, fluoride, chloride) are a a a x WA applies only to PWRs. also required to be present in condusion, the RWCU System is not atfected by the IGSCC Degradation Mechanism due to the fact that all welds are classified as IGSCC Category A per the NRC Genuic Letter 88-01, TGSCC-1 operating temperature > 150*F, ari x a a a TGSCC-2 tensile stress (including residualsts ?,esent, and x a a a TGLCC 3-1 halides (e.g., fluoride, chbonde) are present, or a x a a impurities are controIIed per EPRI Water Che nistry Guidelines. TGSCC-3-2 caus:ic (NaOH)is present, and a x a a TGSCC-4 oxygen or oxidizing species are present (only required to bo x a o a present in conjunction whalides, not required w/ caustic) in conclusion, the RWCU System is not a0cted by the TGSCC Degradabon Mechanism due to the absence of handes and caustics, per EPRI Watu Chemistry Guidelines.

1 e, , s Degradation hfechanism Assmment Worksheet C:nclusions Risk Segment No, No. Attributes to be Considered Remarks l '" l "' l ** l " ECSCC-1 operating temperature > 150*F, and x a a a ECSCC-2 tensile stress is present, and x a a a ECSCC.3-1 an outside piping surfack is within five diametea of a probable a x a a VY compIres with Reg Guide 1.36 leak path (e g., vain stems) andis cowred with non metallic insulation that is not in ,;twnpliance with Reg. Guide 1.36, of ECSCC-3-2 an outside piping surfr is exposed to wetting from chlorir's a x a a bearing environments %.g., seawater, beschish water, brine) in condusion, the RWCU System is not affected by the ECSCC DegradatKv, Mechanism due to the fact that the system ts insulated with norsnetallic irculation per Reg Guide 1.36. PWSCC-1 piping materialis Inconel(Alloy 600), and a x a a PWSCC-2 exposed to primary water at T > 620*F, and a x a a PWSCC-3-1 the materialis mill-annealed and cold worked, or a a x a PWSCC-3-2 cold worked and welded without stress relief a a X a in conclusion, the RWCU System is not affected by the PWSCC Degradation Mechanism due to the fact that this system is not exposed to pnmary watr at T> 620*F and contains no inconel. MIC-1 operating temperature < 150*F, and a y a a MIC-2 low orintermittent flow, and a a x a MIC-3 pH < 10, and a a x a MIC-4-1 presencellntrusion of organic matorial(e.g , raw water system), a o x a or MIC-4-2 water source is not treated wituocides (e.g., refueling water tank) o a x ^ a in conclusion, the RWCU System is not affected by the MIC Degradation Mechanism cue to the fact that this system is expose 6 to an operating temperature greater than 150*F, i PIT-1 potentialexists forlow flow, and a x a a PIT 2 oxygen or oxidizing species are present, and x a a a PIT 3 initiating contaminants (e.g., fluoride, chloride) are present a x a a Initiating contaminants are controlled per EPRI water chemistry guidelines, in condusion, the RWCU System is not affected by the PIT Degradation Mechanism dee to the fact that this system is not exposed to low flow conditions, PIT initiating contaminants per EPRI Water Chemistry Guidelines. I CC-1 crevice condition exists (e.g., thermal sleeves), and a x a a CC-2 operating temperature > 150*F, and x a a a CC-3 oxygen or oxidizir a spsdes are present x a a a in condusion, the P'NCU System is not atfected by the CC Degradation Mechanism due to the fact that this system does not contain crevice conditions. E-C-1 existence of cavitation source (i.e., throttling orpressure a x a a Not within the Class 1 pt.wtion, reducing valves or orilices) E-C-2 operating temperature < 250*F, and a x a a E-C-3 flow present > 100 hrs &r, and a a x a E-C-4 velo'ity > 30 tVs, and a a x a E-C 5 (Pe - P,) / AP < $ a a X a in condushan, the RWCU System is not affected by the EC Degradation Mechanism due to the tact that no cavitation source exists in the system and the operating tempc ature is greater than 250*F. FAC-1 evaluatedin accordance with existing plant FAC program a x a a Majority of the Class 1 portion a SS and not expected to be part of the FAC Program. CS is small segment of piping and appears to not be susceptible.

                                                                                                                                                                                                                                                                                                               * ,    e*

Degradation Mechan'sm Assessment Work:heet Conclusions R):k Segment No. No, Attributes to be Considered Remarks l

l
l "c l "*

in condusion, the RWCU System is not a"ected by the FAC Degradation Mechanism due to the fact that the majority of the system is not induded in tra F AC program (Le., tM system is composed of stainless steel). The remaining CS segment is small and appears to not be susceptible. 1 W:Cr 'O X O O Hammer end 5 s i

l _.__ ___-__ _ _._______ ___- _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ . - . _ _ . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ . _ _ _ _ . _ _ _ . . _ _ _ _ _ _ _ . _ _ _ _ . _ _ _ . _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ _ . _ . _ _ _ _ _ _}}

BVY-97-105, Provides NRC W/Degradation Mechanism Evaluation & Results of Element & Segment Risk Rankings.Util Intends to Submit Revised ISI Program Following NRC Review of Evaluations & Risk Ranking,As Stated in Ltr

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BVY-97-105, Provides NRC W/Degradation Mechanism Evaluation & Results of Element & Segment Risk Rankings.Util Intends to Submit Revised ISI Program Following NRC Review of Evaluations & Risk Ranking,As Stated in Ltr

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