ML19208C858
| ML19208C858 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 08/24/1979 |
| From: | Reed C COMMONWEALTH EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| NUDOCS 7909270579 | |
| Download: ML19208C858 (10) | |
Text
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Commonwealth Edison One First National Plaza, Chicago. Illinois t-Address Reply to: Post Office Box 767 Chicago. Illinois 60690 August 24, 1979 Mr. James G. Keppler, Director Directorate of Inspection and Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137
Subject:
Zion Station Units 1 and 2 Response to I.E.
Bulletin No. 79-17,
" Pipe Cracks In Stagnant Borated Water Systems At PWR Plants".
NRC Docket Nos. 50-295 and 50-304 Reference (a):
July 26, 1979 letter from J. G. Keppler to Byron Lee, Jr. transmitting I.E.
Bulletin No. 79-17.
Dear Mr. Keppler:
Reference (a) required Commonwealth Edison Company to provide a written response to Item 1 of I.E.
Bulletin No. 79-17,
" Pipe Cracks In Stagnant Borated Water Systems At PWR Plants".
Commonwealth Edison's response to the NRC Staff request is contained in Attachment 1 to this letter.
Please address any additional questions that you might have concerning this matter to this office.
Very truly yours, N.? Nw' e
' T cr ti,
- 1. Re d 1 nt Vice-President c
.-c Attachment cc:
Director, Division of Operating Reactors kJS2'#
" **"C1 1043 169
NRC Docket Nos. 50-295 50-304 ATTACHMENT 1 Commonwe-lth Edison Company's Response For Zion Station To a
Item 1 of I.E. Bulletin No. 79-17 1.
Conduct a review of safety related stainless steel piping systems within 30 days of the date of this Bulletin to identify systems and portions of systems which contain stag-nant oxygenated borated water.
These systems typically include ECCS, decay / residual heat removal, spent fuel pool cooling, containment spray and borated water storage tank (BWST-RWST) piping.
(a)
Provide the extent and dates of the hydrotests, visual and volumetric examinations performed per 10 CFR 50.55a (g) (Re:
I.E. Circular 76-06 enclosed) of identified systems.
Include a description of the non-destructive examination procedures, procedure qualifications and acceptance criteria, the sampling plan, results of the examinations and any related corrective actions taken.
(b)
Provide a description of water chemistry controls, summary of chemistry data, any design changes and/or actions taken, such as periodic flushing or recirculation procedures to maintain required water chemistry with respect to pH, B,
C L~,
F~, 0*2 (c)
Describe the preservice NDE performed on the weld joints of identified systems.
The description is to include the applicable ASME Code sections and supplements (addenda) that were followed, and the acceptance criterion.
(d)
Facilities having previously experienced cracking in' identified systems, Item 1, are requested to identify (list) the new materials utilized in repair or replace-ment on a system-by-system basis.
If a renort of this information and that requested above has been previously submitted to the NRC, please reference the specific report (s) in response to this Bulletin.
Response
Zion Station has reviewed the safety related stainless steel piping systems and determined which lines or portions of lines contain stagnant oxygenated borated water.
These lines or portions of lines which are identified in Table 1 are applicable to either Unit 1 or Unit 2.
The table contains the line number and the 1043 170
NRC Docket Nos. 50-295 and 50-304 functional description of each line identified.
Also listed is the nominal pipe diameter, pipe schedule, material specification and nominal wall thickness.
(a)
Extent and Dates of NDE The last column of Table 1 describes whether the line has been examined per 10 CFR 50.55a(g).
Those lines identified as having been examined are listed in Tables 2 and 3 for Units 1 and 2 respectively.
All of the lines in Table 2 were leak tested per ASME Section XI, Articles IWA-5000 and IWB-5000, on May 24, 1976, November 25, 1977, October 27, 1978 and April 2, 1979.
The lines in Table 3 were similarly tested on March 22, 1977, April 7, 1978 and April 5, 1979.
The results of these tests showed no evidence of through wall leakage.
Tables 2 and 3 describe the total number of welds in the identified systems and dates of visual and volu-metric examinations required by ASME Section XI, Tables IWB-2500 and 2600.
The examinations performed through Spring 1978 were in compliance with the 1971 Edition of the Code, up to and including the Summer 1972 Addenda.
Subsequent examinations were in compliance with the 1974 Edition of the Code, up to and including the Summer 1975 Addenda.
The examination procedures, procedure qualifications, acceptance criteria and sampling plans were as required by the aforementioned editions of the ASME Code.
The reported results of the examinations have indicated no evidence of pipe wall degradation.
(b)
Water Chemistry The lines identified in Table 1 are primarily supplied i
with water from the Refueling Water Storage Tanks (RNST).
These tanks are vented to atmosphere and therefore are at 02 saturated conditions (approx. 7.0-10.0 ppm).
The balance of the chemistry is typically:
Boron 2100-2450 ppm as H B0 ; F1 0.01 to 0.2 ppm and pH 5.0-6.7.
From initial 3
4 plant start-up until 1977 the RWST had been experiencing slight Cl contamination from the contaimnent Spray Additive System.
The amounts of Cl found in the RWST and Accumulators during that period were typically 1.0-5.0 ppm.
Changes to the recirculation procedure and the institution of a local flushing procedure in 1977 reduced the Cl-concentrations to a typical range of 0.30-0.50 ppm.
b
$fh
NRC Docket Nos. 50-295 and 50-304 (c)
Preservice NDE All of the welds in the lines identified in Table 1 received construction preservice NDE required by the piping design specifications.
The specific testing requirements are identified in Table 4.
The Code requirements for procedures, acceptance criteria and sampling plans are tabulated for each design speci-fication and are identifiable by the line number suffix.
Additionally, all of the welds in the lines identified in Tables 2 and 3 received hydrotest, visual and ultrasonic examinations in accordance with the preservice inspection requirements of ASME Section XI, 1971 Edition, up to and including Summer 1972 Addenda.
(d)
Previous Cracking Experience Zion Station has not found any cracking on the identi-fied systems.
8 o
1043 172
NRC Docket Nos. 50-295 and 50-304 0
0 TABLE 1 tj 1
PORTIONS OF SYSTEMS IDENTIFIED
~
EU R I. E. BULLETIN 79-17 2 Ub J M A !fu a Wall I.S.I.
Line Number Description Size Schedul_e Mate rial Thickness Performed CS 0 0 8-8" R1 Containment Spray Riser 8"
40S A312-Tp304
.322" No CS 00 9-8 " R1 Containment Spray Riser 8"
40S A312-Tp304
.322 No CS010-8"R1 Containment Spray Riser 8"
40S A312-Tp304
.322" No CS 0 51-10" R1 RNST Level Reference Log 10" 40S A312-Tp304
.365" tio RC008-8"El R.C.S.
Loop 1 Bypass 8"
140 A376-Tp316
.812" Yes RC046-8"El 2 Bypass 8"
140 A376-Tp316
.812" Yes RCll 3-8 "E l 3
RC0 9 0- 8 "E l 4
RC006-10"El Accumulator Discharge Loop 1 10" 160 A376-Tp316 1.125" Yes RC0 4 0- 10 "E l 2
PC080-10"El 3
RC072-10"El 4
RC007-8"El R.H. R. Ilot Leg Return Loop 1 8"
140 A376-Tp316
.812" Yes SIl25-8'El Loop 2 RClll-8 " E l Loop 3 RC083-8"El Loop 4 RC0 6 5-3" E l Alternate Charging 3"
160 A376-Tp316
.438" Yes RC004-14"El R.H. R. Suction 14" 160 A376-Tp316 1.406" Yes RC155-6"El Pressurizer Safety (Loop Trap only) 6" 160 A376-Tp316
.719 Yee RC156-6"El 6"
160 A376-Tp316 RC157-6"El VC100-3"E Alternate Charging 3"
160 A376-Tp304
.438" Partial
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D NRC Docket Num 50 295 and'50-304 DJ dr TABLE 1 (Cont'd)
LJ jtil PORTIONS OF SYSTEMS IDENTIFIED FOR I.E. BULLETIN 79-17
{i[0TJ[]{ifCft A UWLuu!AL Wall I.S.I.
Line Number Description Size Schedule Material Thickness Pe rformed VCl21-8" AA Charging Pump Suction -
M1ST 8"
40S A312-Tp304
.322" No VCl22-8"AA VC094-8"AA
" -RilR SI001-8" L PJIR to Cont. Spray 11eader 8"
40S A312-Tp316
.322 No SI002-8"L R!!00 3-8" L RIIR llot Leg Return 8"
40S A312-Tp316
.322 No A
RII0 0 4-8" L RII00 5-8" L PJ10 0 6-12 " L 12" 40S A312-Tp316
.375 No R!l006-12"E 12" 160 A376-Tp316 1.312 No PJIO 4 3-8 "E RIIR flot Leg Return Loop 1 8"
160 A376-Tp316
.906 Partial SIO23-8"E 1
PJIO 4 4 - 8 " E 3
SIO 2 4-3"E 3
A376-Tp316 SF02 3-3" AA M1ST to Refuel Water Pur. Pump 3"
40S A312-Tp304
.216" No DT032-3"AA 3"
SIO90-3"E B.I.T.
to Cold Log Inj.
3" 160 A376-Tp304
.438" Partial SIO75-4"E Charging Pumps to B. I.T.
4" 120 A376-Tp316
.438 No SIO76-4"E A376-Tp316 120 A376-Tp316 SIO77-4"E SI0 0 3-8" L RIIR to MVST 8"
40S A312-Tp316
.322 No SIO71-8"AA RNST to Charging Pumps 8"
40S A312-Tp304
.322 No SIO73-8"AA MfST to Charging Pumps;.
8" 40S SIO74-8"AA RMST to Charging Pumps 8"
40S n
U
.D=.
NRC Docket Nos. 50-295 and 50-304 TABLE 1 (Cont'd) f
]
D PORTIONS OF SYSTEMS IDENTIFIED gg3J FOR I.E. BULLETIN 79-17 n qq g; q O g
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lj.
im o dU d d J Ud ba Wall I.S.I.
Line Number Description Size Schedule Material Thickness Perfortica
.SIO99-4"G S.I. Pump B Discharge 4"
80S A312-Tp304
.377" No SI l0 0- 4" G S.I.
Pump A A312-Tp304
'SIO99-4"E S.I.
Pump n to IIot Legs 4"
120 A376-Tp316
.438" SIl04-4"E S.I.
A 120 A376-Tp316 No SIl28-4"G S.I. Pumps to Cold Legs 4"
00S A312-Tp304
.377" No SIl28-4"E 4"
120 A376-Tp316
.438 SIO36-10"E Accumulator to Loop 1 10" 160 A376-Tp316 1.125 Partial
\\
SI O 34 - 10 " E 2
SIO32-10E 3
SIO30-10"E 4
SIO36-10"L Accumulator to Loop 1 10" 40S A312-To316
.365 No SIO34-10"L 2
SIO32-10"L 3
SIO30-10"L 4
SI006-12"AA RNST to RIIR 12" 40S A312-Tp304
.375
~
No SI007-18"AA Recirc. Sump to RIIR 18" Std.
A358-C1.1-Tp 304
.375 No SI008-18"AA S I 0 0 7-18" L 40 A35 8-C1.1-Tp 316
.562
'SI008-18"L 40 ne b
U (n
I NRC Docket Nos. 50-295 and 50-304 Dhh[h)D TABLE 2 PORTIONS OF SYSTEMS IDENTIFIED (Uj i U l t p" FOR I.E. BULLETIN 79-17
[
Ik ]ff?lj INSPECTED PER 10CFR50.55a (g) d bl J Lug i{f! /]IL;;L i
ZION UNIT 1 Line Number Total Number Visual and Volumetric Examinations of Welds Number pate Nmmber Date RC0 0 8-8"El 7
RC046-8"El 7
RCll 3-8"El 7
3 Spring'1976 RC09 0- 8" E l 7
RC00G-10"El 7
RC040-10"El 5
RC080-10"El 5
RC072-10"El 5
RC007-8"El 7
1 Spring 1976 5
Fall 1978 SIl25-8"El 19 3
Spring 1976 5
Fall 1978 RC111-8"El 17 RC083-8"El 8
PC065-3"El 9
4 Spring 1976 RC004-14"El 5
i Pall 1978 RC155-6"El 3
RC156-6"El 3
1 Spring 1976 1
Fall 1978 RC157-6"El 1
3 yC10 0- 3" E 1
1 Fall 1978 PH0 4 3-8"E 8
SIO 2 3-8" E RH 0 4 4-8 "E 34 3
Spring 1976 SI-24-8"E SIO90-3"E 22 SIO36-10"E 10 SIO34-10"E 9
5 Fall 1978 SIO32-10"E 11 SIO30-10E 13 5
Spring 1976 CD-4 Led MD
i NPC Docket Nos. 50-295 and 50-304 I
TABLE 3 PORTIONS OF SYSTEMS IDENTIFIED (M D
}p>
l' FO R I. E. BULLETIN 79-17 J UjJ o
INSPECTED PER 10CFR50-55a(g) d FR r C q n gF l !!
- l' 1
l ZION UNIT 2 L UL.JWLaulEula 3
Visual and Volumetric Examinations Line Number Total Number of Welds Number Date Number Date RC008-8"El 7
RC046-8"El 7
PCll3-8"El 7
RC0 9 0- 8" E l 6
RC006-10"El 7
4 Spring 1977 RC0 4 0- 10 " E l 7
RC0 80- 10 " El 6
RC072-10"El 6
RC007-8"El 7
SIl25-8"El 19 5
Spring 1979 RC111-8" E l 16 5
Sprinq 1979 RC083-8"El 8
RC065-3"El 9
RC004-14"El 5
RC15 5-6 "E l 3
RC156-6"El 3
RC157-6"El 3
3 Spring 1977 VC100-3"E 1
1 Spring 1979 RH 0 4 3-8"E 7
4 Spring 1979 SI O 2 3-8 "E-RH 0 4 4-8" E 35 6
Spring 1977 SIO24-8"E SIO90-3"E 18 3
Spring 1979 SIO36-10"E 12 SIO34-10"E 9
SIO32-10"E 10 SIO30-10"E 13 O
J:=
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NRC Docket Nos. 50-295 and 50-304 CO TABLE 4 I'-
CONSTRUCTION NDE REQUI REMENTS FOR PORTIONS OF SYSTEMS IDENTIFIED FOR I.E. BULLETIN 79-17 p,3 v
CD Dye-Penetrant Requirement Piping Design Table Radiography Requirement
_ Root pass and final weld)
(
(Line Number Suf fix Appendix VIII of ASME Section VIII Par. PN-51 of ASME Section I E
N-627.2 and N-627. 3 of ASME N-62 4. 2 and N-62 4. 3 o f ASME Section III El Section III plus Code Core 1443 Appendix VIII of ASME Section VIII Par. PN-51 of ASME Section I G
Par. UW-51 of ASME Section VIII Appendix VIII of ASME Section VIII L
Appendix VIII of ASME Section VIII Par. PW-51 of ASME Section I R-1 Appendix VIII of ASME Section VIII Par. FW-51 of ASME Section I (Root pass on 6 in. and larger dia.
AA (10% sample of weld with and final weld on all welds.)
greater than 0.251 in.
wall thickness.)
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