ML20073F816
| ML20073F816 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 04/24/1991 |
| From: | Taylor D COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation |
| References | |
| IEB-88-008, TAC-M69602, TAC-M69603, NUDOCS 9105030035 | |
| Download: ML20073F816 (2) | |
Text
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F L/
. Ctmmtnwealth Edisen 9., *
- f 1400 0,nus Place d
Downers Grove, Illinois 60516 April _24, 1991~
Office of-Nuclear Reactor Regulation 0.S. Nuclear Regulatory Commission 1
- Attn:
Document Control Desk Washington, D.C.
20555.
Subject:
Braidwood Station Units 1 and 2 Supplemental Response to NRC Bulletin 88-08, Supplement 3 TAC Nos. M69602, M59603 j
HRC Docke_t Nos. 50-454/455
Reference:
(a)!NRC Balletin 88-08, Supplement 3, dated April 11., 1989.
-(b) M. Richter letter to U.S.-NRC, dated July 17,.1989..
(c) M. Richter letter to U.S. NRC, dated November.29,-1989.
L
Dear:
Sir:-
Reference (a) described an event at a-foreign-reactor facility
- (Genkai)-which raised new concerns on thermal stratification in unisolable piping _ connected to the Reactor-Coolant System-(RCS).
The event in Reference (a) occurred due to a valve: leakage phenomenon which was not previously.
considered in NRC Bulletin 38-08 (or Supplements 1 and_2). ; Reference (a)
-requested thatithe,. Actions in NRC Bulletin 88-08 Supplement 3 be addressed.
- A's reported ~in-Reference (b), Commonwealth _ Edison Company-(Ceco)-
. identified two (2) lines associated with the Residual Heat Removal (RHR)
. System:per. unit at Braidwood Station which may be susceptible to cyclic stratific'ation'due tofthe valve. leakage phenomenon described in Reference-
'(a).
To address: Bulletin Actions 2 and 3 for. Braidwood Station, Edisen
-indicated that an evaluationtwas being. performed which would supply the-
~
critical locations on-the-susceptible-piping-for inspectica purposes, and the frequency of future inspections to ensure piping integrityL ' Reference (c) provided.the-results of that evaluation forcBraidwood Station.. Reference (c) also indicated Braldwood Station would be performing non-destructive examinations on the susceptible RHR1 suction-lines at the. critical locations determined from that' evaluation.. Additionally, Reference'(c) indicated
- Braidwood Station would adopt a.long-term inspection program to ensure the integrity.of-the RHR suction lines.
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U.S. Nuclear hegulatory Commission April 24, 1991 As indicated in Reference (c), during the Fall 1989 refueling cutage for Braidwood Unit I non-destructive examinations were performed on the four (4) welds which were identified by the evaluation as critical locations.
The welds examined were IRC-ll-7, 1RC-11-8 and IRC-11-9 on lir.e IP.C04AB and weld 151-02-43 ca line IRC04AA.
The examinations of the welds and associated heat affected zones were performed utilizing enhanced ultrasonic techniques which ensure increased sensitivity for the detection of cracks.
The results of these examinations for Braidwood Unit I revealed that there were no indications found.
The inspections performed fulfills Bulletin Action 2 for Braidwood Unit 1.
During the Spring 1990 refueling outage for Braidwood Unit 2 non-destructive examinations were performed on the four (4) welds which were identified by the evaluation as critical locations.
The welds examined were 2RC-11-7, 2RC-11-8 and 2RC-ll-9 on line 2RC04AB and weld 251-02-44 on line 2RC04AA.
The examinations of the welds and associated heat affected zones were performed utilizing enhanced ultrasonic techniques which ensure increased sensitivity for the detection of cracks.
The results of these examinations for Braidwood Unit 2 revealed that there were no indications found.
The inspections performed fulfills Bulletin Action 2 for Braidwood Unit 2.
The Inservice Inspection (ISI) Program at Braidwood has been revised to include the inspection of these lines (at the critical locations) at a frequency of every other refueling outage.
This letter therefore completes the reporting requirements and action items identified in Bulletin 88-08 Supplement 3 for Braidwood Station Units 1 and 2 Please direct any questions that you may have on this response to this office.
Respectfully, h
?
D.L. Taylor Generic Issues Administrator DT:Imw ZNLD806/24 cc: A.B. Davis - Regional Administrator, Region III R. Pulsifer - Project Manager, NRR Resident inspector - Braldwood l
ZHLD/806/24
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