ML19332G147
| ML19332G147 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/07/1989 |
| From: | Czajkowski C BROOKHAVEN NATIONAL LABORATORY |
| To: | Bernard Grenier Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19332G143 | List: |
| References | |
| CON-FIN-A-3871 NUDOCS 8912200218 | |
| Download: ML19332G147 (9) | |
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BROOKHAVEN NATIONAL LABORATORY
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ASSOCIATED UNIVERSITIES, INC.
Upton. Long is6ord. New York i1973
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(516) 282s 4420 Deportment of Nuclear Energy FT$ 666' July 7, 1989 s
i Mr. Bernard L. Grenier U.S. Nuclear Regulatory Commission NRR/PMSB i
Mail Stop 11-H22 Room 12-H18 l
Washington, DC 20555 Dear Mr. Grenier-Enclosed please find a trip report for the joint NRC/BNL site visit to Millstone Unit 2 in June 1989.
This report is sent to satisfy the requirements of Task Order 4 of FIN A-3871.
If there are any questions, please contact me at the above number.
I trulyyouns,ll Ver yki x
Carl Cz L
CJC:a1
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Enclosure cc w/ enc.:
R. Bari, BNL D. Dilanni, NRC K. Parczewski, NRC (4)
M. H. Schuster, BNL P. Soo, BNL 8912200218 891211 ADOCK0500g6 DR
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BORIC ACID PREVENTlwN Trip Report FIN A-3871 TASK ASSIGNMENT NO. 4 A.
Introduction On June 26 28, 1989, a USNRC audit team visited the Millstone Unit 2 site.
The team was comprised of K. 1. Parczewski of the USNRC and Mr. C. Czajkowski of Brookhaven National Laboratory (BNL).
The purpose of the plant visit was to audit the licensee implemented program for prevention of carbon steel corrosion by boric acid in the reactor pressure boundary of the plant.
This verification of program implementation took the form of an audit of the Units' written procedures, interviews with plant staff personnel and verifying that the techniques used by the utility were proper and performed by adequately trained / certified personnel.
The guidelines for the audit fell into four broad areas of concern which should encompass the utilities' elicited responses to NRC Generic Letter 88 05.
B.
Determination of the princioal locations where leaks of crimary coolant below the specification limits could cause dearadation of the reactor pressure boundary comoonents.
l The utility uses procedure SP21150, Rev. 1, ' Inspection of Category I l
Components Exposed to Boric Acid," May 19, 1988, to provide instructions for the l
examination of Category 1 Components exposed to possible boric acid leakage.
This procedure establishes the following acceptance criteria (page 2, para.
"2.1 No visible leakage or evidence of past leakage (boric acid buildup, general area corrosion, etc.),
2.2 If evidence or leakage is found - No visible loss of fastener material by corrosion. Light rust, with no visible thickness, (no flaking) is acceptable.'
l provide a listing of all of the areas inspected while following this procedure.
These inspections are performed at least once per fueling outage (para. 7.1).
C.
Procedures for locatina small coolant leaks The aforementioned procedure has the following protocol established to l
perform leak inspections:
Page 1 of 7 i
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l 7.
PROCEDURE i
7.1 Perform an inspection of all mechanical joints listed in Figure 9.1 at least once per refueling cycle as follows:
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7.1.1 Remove insulation as necessary for visual access to the closure.
7.1.2 Inspect closure for evidence of leakage or past leakage (Boric Acid Residues, rust, etc.).
7.1.3 Record results on ENG. Form 21150-1. If there is no evidence of leakage, mark other blocks on the forn N/A.
7.1.4 If the inspection of paragraph 7.1.2 indicates present or past leakage, inspect the full length of all fasteners for corrosion. They may require disassembly of the closure.
7.1.5 Record results on ENG. Form 21150 1.
7.1.6 Report any unacceptable fasteners in accordance with reference 3.2 and replace all unacceptable fasteners in accordance with reference 3.1.
In addition to SP21150, Rev. 1, the licensee also has station procedure SP2675, Rev.1, " Containment Entry for RCS Leakage Investigation,' March 15, 1989, which outlines in detail the various areas of containment which are to be visually inspected.
Station Procedure SP2669A, Rev. 5, 'PE0 Rounds," October 1,1986, is a surveillance procedure in effect to list the requirements for monitoring Unit 2 systems and equipment on a shift and daily basis by the Plant Equipment Operators (PEO).
Paragraph 9.8.11.1, 9.8.11.2 and 9.8.16.3 of this procedure specifically require checks for leakage on Safety Inspection Containment Spray systems and Idle Equipment.
Procedure SP2602C, Rev. 3, ' Reactor Coolant System Leak Test / Hydrostatic Test,' December 10, 1986, requires that the RCS. integrity be verified by completing a leak test at m2250 psia and a532'F for at least-four hours and The final hydrostatic testing at a2295 psia and tS32'F for a four hour period.
This inspection is performed after the four hours at time and temperature.
procedure has been revised to incorporate ASME Section XI subsection IWA-5240 in response to IE Notice 86108, ' Degradation of RCS Pressure Boundary Resulting from Boric Acid Corrosion."
Page 2 of 7
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D.
Procedures for evaluatina boric acid induced corrosion of carbon steel components in the reactor pressure boundarv.
The utility uses three systems of reporting leakage of boric acid.
They are:
1)
ACP-QA 10.01, Rev. 29, May 24,1988, ' Plant Incident Report,"
2)
Production Maintenance Management System Program for Trouble Reporting (Computer Program), and j
3)
ACP-QA-5.01, Rev. 21, July 5,1988, 'Nonconfoming Materials and Parts.'
These require different degrees of evaluation depending on severity of problem.
The inspection procedure (SP21150) has the following steps outlined if significant leakage is seen:
"7.2 If boric acid leakage potentially affecting the reactor coolant system pressure boundary is reported in accordance with Reference 3.4, proceed as follows:
7.2.1 Remove insulation as necessary for visual access l
to the component.
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7.2.2 Inspect component for evidence of leakage or past leakage (Boric Acid Residues, rust, etc.). Record I
results on ENG. Form 21150 2.
7.2.3 If the inspection indicates present or past leakage (boric acid residues, rust, material wastage,etc.).
7.2.3.1 Determine the extent of leakage identifying all areas and components which may have been subjected to boric acid leakage.
Record required extent of examination on ENG. Form 21150 2.
7.2.3.2 Remove insulation as necessary to expose areas and materials for examination.
7.2.3.3 If the component is one of those listed in Figure 9.1, remove the closure cover in accordance with reference 3.1 and inspect all fasteners for corrosion.
7.2.3.4 Record results of. examinations on ENG. Form 1
21150 2.
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Report any areas of degradation in 7.2.3.5 accordance with reference 3.2.
Record the Non Conformance Report Number on ENG. Form 21150-2.
If pressure boundary damage affects system 7.2.3.6 integrity, report the extent of damage in Record the accordance with Reference 3.3.
Plant Incident Report Number on ENG. Form 21150 2."
s Corrective actions taken by the licensee to nrevent recurrence of similar E.
tvoes of corrosion.
An essential component of the corrective action program at 28,1987, " Root 1)
Millstone 2 is ACP-QA-10.12, Rev.1, September J
l Cause Assessment Process," which outlines the step by step L
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procedures to evaluate the root cause of significant l
incidents.
Plant incident reports and nonconformance reports were reviewed for three instances for boric acid leakage:
2)
PIR-88-43, ' Plant Shutdown for Rx Leak Repair,"
a) b)
Nonconformance Report 288 069, " Boric Acid Effect on I
R.V. Nozzles," and c)
Nonconformance Report 288 069, " Reactor Vessel Closure Stud Corrosion."
All were conducted in a professional and thorough manner for evalua eventual disposition of the problems.
3)
A plant tour was provided which included the following l
equipment (Unit 2):
Boric Acid Tank Boric Acid Storage Tank and Pumps L
RBAST Pump Recirculation Line Relief Stops A&B Volume Control Tank Charging Pumps AER Waste Drain Tank Valves Containment Sump Header B&A Outlet l
"B" SIS Suction Header Vent Fuel Pool HPSI Pump "A" LPSI Pump "A" Containment Spray Pump Shutdown Cooling Heat Exchanger l
Page 4 of 7
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v During the plant tour, two trouble reports were observed on equipment.
Both These were recorded and then traced through the system for actions taken.
were found to be handled in a satisfactory manner.
Trouble Reoorts
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l TR 12M2062452 TR 09M2104327 Additionally, the team noted a boric acid leak (from a hose).
This was immediately repaired by the utility.
F.
Conclusions 1)
The licensee's program for boric acid corrosion prevention meets the intent of Generic Letter 88-05.
2)
The utility has adequate procedures to satisfy all four areas of concern in the generic letter.
3)
Implementation of the program appears satisfactory.
The above items were discussed with utility personnel in an exit critique.
G.
Documents Reviewed 1.
SP2675 Rev.
1, 3/15/89, " Containment Entry for RCS Leakage Investigation."
2.
USNRC Inspection Report, 50 336/88-B (5/3/88 - 6/13/88), " Routine Resident Inspection," dated 7/7/88.
3.
Station Procedure OP2669A-2, Rev. 9,11/23/68, Charge No. 5, " Plant Equipment Operator (PEO) Rounds."
4.
SP2602C, Rev. 3, Charge 2, 4/1/87, "RCS Leak Test / Hydrostatic Test."
5.
Letter - Northeast Utilities to USNRC, dated 5/27/88, Subject -
Response to Generic Letter 88 05.
6.
LER, 0500336 - 04/08/88 - 008-01, " Unrecoverable Dropped CEA."
7.
ACP-QA-10.12. Rev. O, 9/28/87, " Root Cause Assessment Proces:;."
8.
ACP-QA 5.01, Rev. 21, 7/5/88, " Nonconforming Materials and Parts."
9.
ACP-QA-2.02C, Rev. 20, 3/8/89, " Work Orders."
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10.
SP21150, Rev. 1, 5/19/88, " Inspection of Category 1 Components Exposed to Boric Acid."
11.
ACP-QA-10.01, Rev. 29, 5/24/88, " Plant incident Report."
Page 5 of 7
12.
MP2701A, Rev.
3, Charge No.
1, 2/20/89, " Structural Integrity Following Repairs on Replacements."
)
13.
Nonconformance Report, 288-069, 5/17/88, ' Boric Acid Effe:ts on R.V.
j
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Nozzles."
14.
Nonconformance Report, 288 069, 5/14/88, ' Reactor Vessel Closure l
Stud Corrosion.*
15.
Plant Incident Report, 88-43, 5/9/88, " Plant Shutdown for Rx Leak Repair."
Controlled Routing Responses to IE Information Notice No.86-108, 16.
" Degradation of Reactor Coolant System Pressure Bourdary Resulting from Boric Acid Corrosion," Supplement 2.
Letter Northeast Utilities, M.F. Ahern to P.J. Parulis, dated 17.
8/22/88, Subject - Reactor Vessel 0 Ring Deposits.
Letter Combustion Engineering to Northeast Utilities, 6/2/88, 18.
Subject - Reactor Vessel Flange Visual Inspection.
19.
Production Maintenance Management System Readouts for Trouble Reports:
t 12H20b2452 open completed 13M2130533 completed
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13H2131239 completed 13M2134544 completed 13M2134933 09M2104327 open l
Letter B.S. Kaufman/H.C. Stout to Distribution,12/7/88, Subject -
20.
ASME Section XI Qualifications of Licensed Operators and Plant Equipment Operations (PE0's).
H.
Personnel Interviewed 1.
The following were interviewed during the site visit:
J. Resetar Asst. Engr. Supr.
J.S. Keenan NNECO Unit 2 Supt.
P. Parulis NNECO Unit 2 Engr.
W.E. Hutchins NUSCO Licensing The following personnel were present at the Exit Critique:
2.
K. Parczewski NRC/NRR C. Czajkowski BNL P. Habighorst NRC (Resident) l P. Parulis Unit 2 Engr.
J. Resetar Unit 2 Engr.
S. Scace Site Supt.
Page 6 of 7
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SP 21150 Pcg3 S ATTACHMENT A Rev. 1 Figure 9.1 Category 1 Closures Exposed to Boric Acid Which Utilite Carbon or low Alloy Steel Bolting t
1; Reactor Coolant Pump A 2.
Reactor Coolant Pump +B l
3.
Reactor Coolant Pump C 4.
Reactor Coolant Pump D 11' 5.
Steam Generator No. 1.
Manway t
6.
Steam Generator No. 2.
Manway 7.
Safety Injection Tank A Manway t
8.
Safety Injection Tank A Instrument Flanges 9.
Safety Injection Tank B Manway 10.
Safety Injection Tank B' Instrument Flanges 11.
Safety Injection Tank C Manway 12.
Safety Injection Tank C Instrument Flanges 13.
Safety In'jection Tank D Manway 14.
Safety Injection Tank D Instrument Flanges 15.
Pressurizer Manway
'16.
Boric Acid Storage Tank A Manway 17.
Boric Acid Storage Tank B Manway 1
18.
A Shutdown Cooling Heat Exchanger Ne.nd 19.
B Shutdown Cooling Heat Exchanger Head A Spent Fuel Pool Cooling Heat Exchanger Head 20.
21.
B Spent Fuel Pool Cooling Heat Exchanger Head r
- 22.. Boric Acid Pump A - Casing to Cover 23.
Boric Acid Pump B - Casing to Cover 24.
HPSI Pump A - Casing Halves 25.
HPSI Pump B - Casing Halves-26.
HPSI Pump C - Casing Halves 27.
LPSI Pump A - Casing to Cover l
28.
LPSI Pump B - Casing to Cover Containment Spray Pump A - Casing to Cover 29.
30.
Containment Spray Pump B - Casing to Cover 31.
Spent Fuel Pool Cooling Pump A - Casing to Cover Spent Fuel Pool Cooling Pump B - Casing to Cover 32.
Page 7 of 7
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bocumentName:
' TAC 73008 L.
Requestor's ID:
DAVIS-Author's Name:
gvissing i
Document Consents-prevention of boric acid corrosion GL 88-05 t
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