ML20217M939
| ML20217M939 | |
| Person / Time | |
|---|---|
| Site: | Paducah Gaseous Diffusion Plant |
| Issue date: | 03/31/1998 |
| From: | Toelle S UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | Paperiello C NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| GDP-98-0063, GDP-98-63, NUDOCS 9804080261 | |
| Download: ML20217M939 (2) | |
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.USEC A Global Energy Company March 31,1998 GDP 98-0063 Dr. Carl J. l'aperiello Director, Office of Nuclear Material Safety and Safeguards Attention: Document Control Desk.
. United States Nuclear Regulatory Commission Washington, D.C. 20555-0001
. Paducah Gaseous Diffusion Plant (PGDP)
Docket No. 70-7001 Status ofImpact Assessment of Updated Seismic Hazard
Dear Dr. Paperiello:
By letter dated February 23,1998 (Reference 1), USEC provided the NRC a status of the impact assessment of the updated seismic hazard on the final design of the seismic modifications to Buildings C-331 and C-335 and on the structural, piping, and equipment analyses reported in the SAR Update (Reference 2). USEC's February 23,1998 letter contained the following commitment:
By March 31,1998, USEC will submit to the NRC a status of the assessment, including completed results as of that date.
Additionally, USEC submitted by letter dated March 6,1998 (Reference 3) a revision to the updated seismic hazard which refines the vertical component ofv av. ion.
/
0 Results of the impact assessment completed to-date show that the updated seismic hazard exceeds that used in the SAR Update. The exceedance, particularly in the vertical direction, has the potential to impact the previous evaluations. Acceleration response spectra (ARS) have been generated using the updated seismic hazard. The horizontal ARS is unaffected from that previously used, while the Tertical ARS has increased in some frequency ranges.
The assessment of the final design of the seismic modifications to Buildings C-331 and C-335 has been completed. Because the design of the modifications is based on the peak vertical acceleration which has not been changed, it has been concluded that the design will satisfy the updated seismic hazard defined in Reference 3.
l 9604080261 980331 PDR ADOCK 07007001 C
PDR 6903 Rocidedge Drive, Bethesda, MD 20817-1818 Telephone 301-564-3200 Fax.301-564-3201 http://www.usec.com Offices in Livermore, CA Paducah, KY Portsmouth, OH Washington, DC
4, < W
- Dr. Carl J. Paperiello
- : March 31,1998 GDP 98-0063, Page 2.
Current efforts are focused on the structural evaluations of Buildings C-310/C-310-A and C-315 in support of USEC's commitment to complete piping and equipment modifications in these buildings by September 30,1998 (Reference 4).
The impact assessments for the remaining buildings and equipment have been temporarily placed on hold pending a better understanding of the NRC's acceptance of the updated seismic hazard.
Should you have any questions related to this subject, please contact Steve Routh at (301) 564-3251.
There are no new commitments contained in this submittal.
' Sincerely,
'b.M ko d g
.- Steven A. Toelle Nuclear Regulatory Assurance and Policy Manager
References:
1.
Letter from Steven A. Toelle (USEC) to Dr. Carl J. Paperiello (NRC), " Status l.
of Impact Aseessment of Updated Seismic Hazard," Paducah Gaseous Diffusion Plant, Letter No. GDP 98-0029, February 23,1998.
'.2.
' Letter from James H.. Miller (USEC) to Dr. Carl J. Paperiello (NRC),
" Certificate Amendment Request - Update the Application Safety Analysis Report," Paducah Gaseous Diffusion Plant, Letter No. GDP 97-0188, October 31,1997.
3.
Letter from _ Steven A. Toelle (USEC) to Dr. Carl J. Paperiello (NRC),
" Compliance Plan Issue 36 - Transmittal of Revision to Updated Seismic Hazard Analysis for NRC Approval," Paducah Gaseous Diffusion Plant, l
- Letter No. GDP 98-0040, March 6,1998.
- 4. 4 Letter from James H. Miller (USEC) to Dr. Carl J. Paperiello (NRC), " Action
- Plan for Postulated Seismic Failures in Buildings C-310/310-A and C-315,"
Paducah Gaseous Diffusion Plant, Letter No. GDP 98-0046, March 11,' 1998.'
' cc:
Mr. Robert C. Pierson, NRC HQ
.NRC Region Ill Office NRC Residentinspector-PGDP '
NRC Resident Inspector-PORTS
. Mr. Randall M. DeVault (DOE) i i