ML20093E975
| ML20093E975 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 10/09/1995 |
| From: | Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-80-13, NUDOCS 9510170201 | |
| Download: ML20093E975 (3) | |
Text
Station Support Depirtment IEB 80-13 v
PECO ENERGY reco e erav o ae"v c
Nuclear Group tieadquarters
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965 Chesterbrook Boulevard Wayne, PA 19087 5691 October 9,1995 Docket No. 50 278 Ucense No. DPR-56 U.S. Nuclear Regulatory Commission Attn: Document Control Center Washington, DC 20555
Subject:
Peach Bottom Atomic Power Station, Unit 3 Core Spray in-Vessel Piping
References:
1)
Letter from G. A. Hunger, Jr. (PECO Energy) to U.S. Nuclear Regulatory Commission da%d November 5,1993 2)
Letter from G. A. Hunger, Jr. (PECO Energy) to U.S.~ Nuclear Regulatory Commission dated November 10,1993 3)
Letter from S. Dembeck (NRC) to G. A. Hunger, Jr. (PECO Energy) dated November 16,1993 4)
Letter from G. A. Hunger, Jr. (PECO Energy) to U.S. Nuclear Regulatory Commission dated December 8,1993 5)
Letter from G. A. Hunger, Jr. (PECO Energy) to U.S. Nuclear Regulatory Commission dated June 13,1995 6)
Letter from G. A. Hunger, Jr. (PECO Energy) to U.S. Nuclear Regulatory Commission dated September 28,1995
Dear Sir:
The purpose of this letter is to identify PECO Energy's corrective actions associated with crack indications identified in the Peach Bottom Atomic Power Station (PBAPS), Unit 3 Core Spray (CS) system, and to request NRC approval to resume operation. This letter is submitted in accordance with IE Bulletin 80-13, " Cracking in Core Spray Spargers," which requests that licensees submit an evaluation of crack indications for NRC approval, prior to returning to operation.
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9510170201 951009 gO l
PDR ADOCK 05000278 Q
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Octob:r 9,1995 Page 2 The PBAPS," Unit 3 CS system consists of four downcomers in the reactor vessel, two downcomers per loop. In References 1 and 2, PECO Energy provided the NRC with details and an evaluation of a crack Indication on the 'D' CS downcomer. This crack indication was identified during refueling outage 3R09. NRC approval for one cycle of operation was provided in Reference 3. Additionalinformation was provided in Reference 4. In References 5 and 6, PECO Energy provided proposed actions associated with the crack indication on the 'D' downcomer. As stated in Reference 6, however, PECO Energy indicated that the proposed actions would be reassessed if the visual examination to be conducted during 3R10 revealed cracking beyond what was projected.
During the current refueling outage 3R10, visual examinations identified additional crack indications on the 'A' and 'C' downcomers. Subsequently, ultrasonic (UT) examinations were performed on all four CS downcomers. These examinations also identified cracking on the "B' downcomer. The cracks on all four downcomers are located on the outer sleeve of a sleeved-pipe connection. Specific details of the UT examinat:ons were discussed with the NRC during an October 6,1995 telephone call, and are included in the Attachment to this letter.
PECO Energy will be installing a repair clamp on each of the four CS downcomers. This repair modification was reviewed in accordance with 10 CFR 50.59. A previous revision of the modification package was reviewed by the NRC and documented in Inspection Report 50-277/9518 and 50-278/9518.
Based on completion of the modification, PECO Energy requests NRC approval to resume operation. Because the modification installs a permanent repair for each of the identified cracks, PECO Energy requests that approval not be limited to a specific cycle of operation.
The Plant Operations Review Committee has reviewed this request. As indicated in previous discussions, resolution of this issue is critical path with respect to completing the current refueling outage. Accordingly, your prompt response is appreciated.
if you have any questions please feel free to contact us.
[
f G. A. Hunger, Jr., Director Licensing Attachment cc:
T. T. Martin, Administrator, Region I, USNRC W. L. Schmidt, USNRC Senior Resident inspector, PBAPS i
PEACH BOTTOM ATOMIC POWER STATION, UNIT 3 CORE SPRAY DOWNCOMER CSL 920Dd24P001
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DOWNCOMER CORE SPRAY CRACK LENGTH LOOP (APPROX. DEG.)"
A (AZ 352.5*)
A 180 B (AZ 7.5 *).
B 128 C (AZ 187.5 *)
A 280 D (AZ 172.5*)
B 250 4
" Not contmuous, summation of total crack lengths.
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