ML031560735
| ML031560735 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 07/23/2002 |
| From: | Jocelyn Craig NRC/EDO/AO |
| To: | Beall J, Croteau R, Hiltz T, Hoeg T, Bradley Jones, Lopez-Otin M, Rathbun D, Sharkey J, Tschiltz M NRC/OCM |
| References | |
| FOIA/PA-2003-0018 | |
| Download: ML031560735 (2) | |
Text
Internal Use Only - Not For Public Disclosure UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 23, 2002 NOTE TO COMMISSIONER ASSISTANTS OCWlGJD 0CMND X Dennis Rathbun X
Brad Jones X
Mike Tschiltz Cynthia Jones Alan Levin X
Tom Hiltz
_ Jennifer Uhle Joe Olencz X.TimothyHoeg KerriKavanagh Keith McConnell Donna Smith Christiana Lul Noble Green Bob McOsker Marian Zobler Karen Henderson Clare Kasputys Barbara Gabriel Linda Herr Terry Agn FROM:
hn W. Craig Assistant for Operations, 0 DO X Maria Lopez-Otin Roger Davis
-X.' ;Rick Croteau1-
_ Diane Flack
_ Doug Simpkins
_ Vicki Bolling
_ Kia Jackson X Jeffry Sharkey Kathryn Winsberg X James Beall
_ Heather Astwood
_ Linda Lewis Judy Ledbetter
SUBJECT:
STATUS OF SDP FOR DAVIS-BESSE RPV HEAD Attached for your information is a summary of the status of the significance deterinnation process for the Davis-Besse Vessel'head degradation.
Attachment:
As stated cc: W. Travers, EDO (w/o attachment)
C. Paperiello, DEDMRS (wlo attachment)
W. Kane, DEDR (w/o attachment)
P. Norry, DEDM (wlattachment)
J. Craig, AO (w/attachment)
S. Rosenberg, OEDO (wlattachment)
B. Sheron, NRR (wlo attachment)
D BY NJD-_
SECY (w/attachment)
OGO (w/attachment)
OCA (w/attachment)
OPA (wlattachment)
OIP (w1o attachment)
CIO (wlo attachment)
CFO (w/o attachment)
EDO R/F (w/atta'chment)
L 2 _I.
0.D OCM/RM OCM/EM 4
-., RP, I
Internns lQic f)-l11 -
_+
r__
Status of SDP Risk Assessment for Licensee Performance Deficiency that Resulted in the Cavity In the Davis-Besse RPV Head 7/18/02 Status:
Region 3 sent TIA for assistance with phase 3 SDP risk assessment.
Dated May 3, 2002 Requested completion by June 14, 2002, but Region is 'flexible" in recognition of difficulties NRR has scheduled completion by August 31.
Reason for delay beyond requested date is expected availability dates for necessary inputs from RES, plus need to support analysis through licensee response stage and final SDP.
0350 Panel was briefed on status at July 11 internal meeting.
If RES and/or FENOC provide cav'ity size estimates for failure at normal RCS pressures by end of July, preliminary SDP can be completed in early August.
Will conduct internal NRR review to Division Directr level and bref ET before transmission to Region.
SERP could be conducted in August Regulatory Conference can be scheduled 30 days after Inspection Report is issued.
Final SDP by September 30 if no difficult issues raised at Regulatory Conference Performance ssue:
Licensee failure to inspect or disposition condition reports in a manner sufficient to detect and correct RCS pressure boundary leakage and cavity formation over multiple cycles.
ACDF considers sum of 3 types of accident sequences:
- 2. cavity grows larger before discovery, and ruptures during normal operation or transient,
- 3. wetted annulus allows nozzle to develop critical circumferential flaw and eject nozzle.
Size of cavity that would fail at normal RCS pressure is not available. RCS and FENOC have slipped dates for providing this information to the end of July. Other necessary info is available.