ML13302B175
| ML13302B175 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon, San Onofre  |
| Issue date: | 09/30/1981 |
| From: | Tedesco R Office of Nuclear Reactor Regulation |
| To: | Atomic Safety and Licensing Board Panel |
| Shared Package | |
| ML13302B177 | List: |
| References | |
| TASK-AS, TASK-BN-81-25 BN--81-25, BN-81-25, NUDOCS 8110190016 | |
| Download: ML13302B175 (3) | |
Text
SEP 3
0 1981 Docket Nos.:
50-361, 50-362 and 50-275, 50-323 MEMORANDUM FOR:
Atomic Safety and Licensing Boards for Diablo Canyon 1 & 2 and San Onofre 2 & 3 FROM:
Robert L. Tedesco, Assistant Director for Licensing, DL
SUBJECT:
BOARD NUTIFICATION - THERMAL-SHOCK TO.PWR REACTOR PRESSURE VESSELI (N-81-2:5)
This memorandum is a followup to our memorandum to you dated May 8, 1981 (BN-81-06) concerning PWR pressure vessel thermal shock.
Enclosed are SECY-81-286A dated September 8, 1981; briefing material from the September 15, 1981 Commission briefing on thermal shock; and a-letter report from J. H. Smith (ORNL) to W. Hazelton (NRC) concerning Oconee Unit 1 vessel inspection.
The conclusion of the staff (as stated in the enclosures) remains that there is no need for immediate licensing action based on pressurized thermal shock considerations for any operating reactor. As stated in our August 21, 1981 letter to Met-Ed (attached to SECY-81-286A) and seven other licensees, all plants could survive a severe overcooling event for at least another year of full power operation based on the staff's independent review. However, the staff believes that additional action as outlined in the enclosures is warranted now to ensure that risks of vessel failure remain sufficiently low to support continued operation of licensed PWRs.
The enclosed ORNL report identifies flaws discovered in the Oconee Unit 1 vessel during a recent inservice inspection. It should be noted that the magnitude of these flaws is well within acceptable limits permitted by ASHE code and as such, do not present unacceptable risks to public health and safety.
[O"ginal signecd )
RobOrt L. Tedesco Robert L. Tedesco, Assistant Director for Licensing Division of Licensing
Enclosures:
As stated cc:
See next page
- SEE PREVIOUS WHITE FOR CONCURRENCE OFFICE)D DL:LB#3*
DL:LB#3*
DL:LB#3*
DL:LB#1*
- DL:AD/L DL:
SURNAME WK/q BBuckley HRood FMiraglia BJYgbl ood RLees D
ut DATEh 9/18/81--81-9/ 9/81.
9//8 9
/81edesc 1
8_ 110190016 610930
____________1 ___________________
........................... I..................
PDR ADOCK 00007USPO 1980-3294 NcA PDR )
OFFICIAL RECORD COPY
Docket Nos.:
50-361, 50-362 and 50-275, 50-323 MEMORANDUM FOR:
Atomic Safety and Licensing Boards for Diablo Canyon 1 & 2 and San Onofre 2 & 3 FROM:
Robert L. Tedesco, Assistant Director for Licensing, DL
SUBJECT:
BOARD NOTIFICATION - THERMAL SHOCK TO PWR REACTOR PRESSURE VESSELS (BN )
This memorandum is a followup to our memorandum to you dated May 8, 1981 (BN-81-06) concerning PWR pressure vessel thermal shock.
Enclosed are SECY-81-286A dated September 8, 1981; briefing material from the September 15, 1981 Commission briefing on thermal shock; and a letter report from J. H. Smith (ORNL) to W. Hazelton (NRC) concerning Oconee Unit 1 vessel inspection.
The conclusion of the staff (as stated in the enclosures) remains that there is no need for immediate licensing action based on pressurized thermal shock considerations for any operating reactor. As stated in our August 21, 1981 letter to Met-Ed (attached to SECY-81-286A) and seven other licensees, all plants could survive a severe overcooling event for at least another year of full power operation based on the staff's independent review. However, the staff believes that additional action as outlined in the enclosures is warranted now to ensure that risks of vessel failure remain sufficiently low to support continued operation of licensed PWRs.
It should be noted that the enclosed ORNL report identifies flaws discovered in the Oconee Unit 1 vessel during a recent inservice inspection. Although it is possible that flaws of this depth and length exist in the M.I-) vessel, the magnitude of these flaws is well within acceptable limits permitted by ASME code and as such, do not present unacceptable risks to public health and safety.
Robert L. Tedesco, Assistant Director for Licensing Division of Licensing
Enclosures:
As stated cc:
See next page
- CFF PPFVTS WHT!FOlR CQNCURRENCES.
OFFICE L
DL:LB#3*
DL:LB#3*
DL:LB#3*
DL:LB1D L
UL:UIR SURNAME I W*a O...
..... ey
.g..l"..........
BJTY'dib 06'd RLTedesco.... Ei-senbut-.....
AMEO 9 H.1........./811 9//81.
..9/..../8-1........../.8.1......... 9/..../.8.1.........
DATEO 7811-B
.o.).......
nU...........
NRC FORM 318 (10/80) NRCM 0240 OFFICIAL RECORD COPY USGPO: 1980-329-824
SEP 3 0 1981 BOARD NOTIFICATION DISTRIBUTION (BN 81-25)
Docket Files 50-361, 50-362, 50-275, 50-323 LB#1 Rdg.
LB#3 Rdg.
D. Eisenhut/R. Purple NRC PDR B. J. Youngblood A. Schwencer F. Miraglia J. Miller E. Adensam W. Kane M. Rushbrook J. Lee R. Vollmer T. Murley D. Ross S. Hanauer B. Snyder R. Hartfield, MPA OELD OIE (3)
H. Denton/E. Case PPAS (H. Thompson)
E. Hughes bcc: W. J. Dircks V. Stello