ML19259B508
| ML19259B508 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 02/06/1979 |
| From: | Rolonda Jackson Office of Nuclear Reactor Regulation |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| TAC-6605, NUDOCS 7903010329 | |
| Download: ML19259B508 (2) | |
Text
f UNITED STATES yV y'1 NUCLEAR REGULATORY COMMISSION
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WASHINGTON, D. C. 20555
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February 6, 1979 MEMORANDUM FOR:
A. Schwencer, Chief Operating Reactors Branch No. 1, 00R FROM:
Robert E. Jackson, Acting Branch Chief Geosciences Branch, DSE
SUBJECT:
BEAVER VALLEY POWER STATION UNIT NO. 1 -
S0ILS STUDY.(TAC N0. 6605)
PLANT NAME: Beaver Valley - Unit 1 LICENSING STAGE: Post OL DOCKET NUMBER:
50-334 RESPONSIBLE BRANCH: ORD No. 1, D. Wigginton, PM APPLICATION RESPONSE DATE: N/A REVIEW STATUS: Continuing The purpose of this memorandum is to document information which has been developed since the January 26, 1979 meeting with Duquesne Light Company at the project site.
The request by Duquesne Light Company to adopt a design ground acceleration of 0.10g for Unit 1 on an interim basis (Refer to Minutes of January 26, 1979 meeting) is acceptable to the Geosciences Branch. This acceptance is based on our recognition that the probability of occurrence for the propossd earthquake with a ground acceleration of 0.10g is not significantly larger than the established DBE of 0.125g during the temporary period (estimated to range from 6 months to 2 years) that foundation treatment measures will be completed.
On February 2, 1979 the Geotechnical Engineering reviewer for Beaver Valley Unit 1, Joseph Kane, was requested by DDR to estimate what river flood level could develop and, when assumed coincident with the OBE (0.06 ), would still permit an acceptable margin of safety 9
against liquefaction of 1.5 to be available. The results of our calculation indicate the flood level under the above assumed conditions would be Elevation 699. The limiting flood elevation for HOT STAND 3Y which was administratively self-imposed by Duquesne Light Company at the January 26, 1979 meeting is Elevation 680. The current technical specification on flood protection requires plant shutdown when the river level reaches Elevation 695.
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A. Schwencer =
To keep abreast of the current problem we recommend continued close e
coordination between the Applicant and the NRC staff. The alternate foundation stabilizing methods currently being studied by Stone and Webster should be provided for Geosciences Branch review prior to beginning actual construction. This recommendation is an attempt to avoid the Applicant completing costly remedial work which later could be determined to be unacceptable to the NRC.
We anticipate completing review of the Applicant's responses to our first three questions by early March 1979. These questions had been transmitted with your letter of January 9, 1979 to C. N. Dunn, Vice-President, Duquesne Light Company.
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Robert E. Jac' son, Acting Branch Chief Geosciences ranch Division' Site Safety and
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Environmental Analysis cc:
R. Boyd R. DeYoung D. Muller V. Stello R. Denise L. Hulman J. Knight L. Heller W. Bivins D. Wigginton T. Johnson
'-. Reiter R. McMullen J. Kane PDR ii T
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