ML20202E037
| ML20202E037 | |
| Person / Time | |
|---|---|
| Site: | Paducah Gaseous Diffusion Plant |
| Issue date: | 12/01/1997 |
| From: | Toelle S UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | Pierson R NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| Shared Package | |
| ML20202E042 | List: |
| References | |
| GDP-97-0201, GDP-97-201, NUDOCS 9712050226 | |
| Download: ML20202E037 (4) | |
Text
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United St:t:s Ennchm:nt Corr: oration 2 Democracy Ccnt:t l'
6903 neckledge Drbe Bethesda. MD 20817 k
Tel. (301) $64 3200 Fa1:(301)$64 3201 December 1,1997 Mr. Robert C. Pierson SERIAL: GDP 97 0201 Chief, Special Projects llranch Division of Fuel Cycle Safety and Safeguards, NMSS United States Nuclear Regulatory Commission Washington, D.C. 20555 0001 Paducah Gaseous Diffusion Plant (PGDP)
Docket No. 70-7001 Compliknee Plan issue 36 - Transinitial of Updated Seismic Risk Analysis for NRC Approval
Dear Mr. Pierson:
Item 4 of the Plan of Action and Schedule (PAS) for issue 36 of DOE /ORO 2026, " Plan for Achieving Compliance with NRC Regulations at the Paducah Gaseous Diffusion Plant"(the Compliance Plan) states:
"4.
By December 1,1997, USEC shall submit for NRC approval an updated seismic risk analysis for the Paducah plant site. The analysis shall:
Consider all available regional and site-specific data published by the U. S.
Geological Survey, Provide an estimate of the peak ground acceleration for a seismic event with a 250-year return period, if the estimate is greater than 0.15g, then the return period for a 0.15g event shall also be estimated.
Any proposed modifications that may result from this analysis shall be subject to a backfit analysis pursuant to 10 CFR 76.76(b)."
In response to this Compliance Plan item, Enclosure 1 provides a copy of the updated seismic risk analysis for NRC approval. The enclosed report," Updated Probabilistic Seismic Ilazard Analysis for the Paducah Gaseous Diffusion Plant, Paducah, Kentucky" was prepared by Risk Engineering, Inc. for USEC.
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hir. Robert C. Pierson December 1.1997 ODP 97 0201 Page 2 The updated analysis considers all available regional and site specine data published by the U. S.
Geological Survey. The results of the study indicate that the peak ground acceleration (pga) for a 250-year return period seismic event is 0.165g. This value slightly exceeds the 0.15g pga value used by the Department of Energy (DOE)in their analyses performed for the site wide FSAR Upgrade (see Reference 1). ('ihe DOB site-wide FSAR Upgrade analyses based on 0.15g were also incorporated into USEC's SAR Update submittals. See References 2 and 3.) llowever, except at vibratory frequencies greater than 35 hz and under I hz, the updated acceleration response spectra is enveloped by that used in the DOE FSAR Upgrade analyses. The return period for a 0.15g event is estimated to be 220 years.
The impact of the updated seismic hazard on (1) the structural, piping, and equipment analyses reported in Reference 3 and (2) the design of the planned structural modifications to 11uildings C 331 and C-335 required by item 1 of the PAS for Compliance Plan issue 36 (see Reference 4) is being assessed.
By February 23,1998, USEC will submit to the NRC a status of that assessment, including completed results as of that date.
As discussed in a telephone conversation between hir. Stephen Routh (USEC) and his. hierri llorn (NRC) on November 18,1997, USEC would appreciate the opponunity to present the results of the updated seismic hazard analysis to the NRC. Please let me know when such a presentation can be scheduled.
Should you have any questions related to this subject, please contact Steve Routh at (301) 564-3251.
Commitments contained in this letter are identified in Enclosure 2.
Sincerely.
- 5. A. IY$
Steven A. Toelle Nuclear Regulatory Assurance and Policy hianager
Enclosures:
1.
Updated Probabilistic Seismic llazard Analysis for the Paducah Gaseous Diffusion Plant, Paducah, Kentucky, Risk Engineering, Inc., November 24, 1997.
2.
Commitments Contained in this Submittal cc:
NRC Region 111 Office NRC Resident inspector-PGDP NRC Resident inspector-PORTS Mr, Randall hl. DeVault (DOE)
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i hir. Robert C. Pierson December 1,1997 GDP 97 0201 Page 3 References
- 1. KY/Ehi 174, " Safety Analysis Report. Paducah Gaseous DifTusion Plant, Paducah, Kentucky,"
Revision 0 A, as transmitted by the February 14,1997 DOE Letter from Joe W. Parks (DOE) to George P. Rifakes (USEC).
- 2. USEC Letter from James,11. hiiller (USEC) to Dr. Carl J. Paperiello (NRC), Certificate Amendment Request - Update the Application Safety Anelysis Report, USEC Letter GDP 97 0148, dated August 18,1997.
- 3. USEC Letter from James.11. hiiller (USEC) to Dr. Carl J. Paperiello (NRC), Certificate Amendment Request - Update the Application Safety Analysis Report, USEC Letter GDP 97 0188, dated October 31,1997.
- 4. USEC Letter from James,11. hiiller (USEC) to Dr. Ce.rl J. Paperiello (NRC), Final Design Information for Planned Structural hiodifications to Buildings C-331 and C-335, Compliance Plan issue 36. USEC Letter GDP 97 0138, dated July 31,1997.
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Enclosure I to GDP 97-0201 Updated Probabilistic Seismic Ilarard Analysis for the Paducah Gaseous Diffusion Plaat, Paducah, Kentuchy, Risk Engineering, Inc.,
November 24,1997 V-a J
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GDP 97-0201 Page1of1 Gunmillnents Contained in this Stilunillal
- 1. The impact of the updated seismic o card on (1) the structural, piping, and equipment analyses reported in Reference 3 and (2) the design of the planned structural modifications to lluildings C-331 4
and C 335 required by item 1 of the PAS for Compliance Plan issue 36 (see Reference 4)is being assessed. Ily February 23,1998, USEC will wbmit to the NRC a status of that assessmen.1, including completed results as of that date.
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