ML20195E184
| ML20195E184 | |
| Person / Time | |
|---|---|
| Issue date: | 04/06/1999 |
| From: | Dicus G NRC COMMISSION (OCM) |
| To: | Vietticook A NRC OFFICE OF THE SECRETARY (SECY) |
| Shared Package | |
| ML20195E165 | List: |
| References | |
| SECY-99-074-C, SECY-99-74-C, NUDOCS 9906100217 | |
| Download: ML20195E184 (2) | |
Text
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N_OTATION VOTE RESPONSE SHEET TO:
Annette Vietti-Cook, Secretary FROM:
COMMISSIONER DICUS
SUBJECT:
SECY-99-074 - STAFF REVIEW OF U.S. DEPARTMENT OF ENERGY VIABILITY ASSESSMENT FOR A HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY AT YUCCA MOUNTAIN, NEVADA Approved x
Disapproved Abstain Not Participating COMMENTS:
See attached comments A
Mew ATUtift 0
&M&
1997 DATs Entered on "AS" Yes x
No
- 7a'288Fe 7J882 CORRESPONDENCE PDR i
i
Commissioner Dicus' Comments on SECY-99-074
)
I approve the proposed letter to DOE that transmits NRC comments on the Viability Assessment, subject to the following modification. I suggest that the following paragraph be added at the top of page 2 of the letter to addresses the issue of defense-in-depth with respect to the repository.
l The staff notes that in the TSPA-VA, DOE placed heavy rehance on engineered barriers (e.g., waste package performance, cladding credit, etc.) to achieve isolation. In addition, the discussion of " defense-in-depth" in the LA Plan considers additional engineered features (drip shields, backfill, ceramic coatings) to compensate for uncertainty and provide margin of safety. In the Statement of Considerations for proposed 10 CFR Part 63, the Commission stated its expectation that natural and engineered barriers would each make a definite contribution to the isolation of waste in order to provide reasonable assurance that the overall safety objective would be met. In any future license application, DOE is expected to j
demonstrate that natural barriers and the engineered barrier system work in combination to enhance overall performance of the geologic repository.
Additional attention needs to be given to how this demonstration will be i
- made, i
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