ML16245A449
| ML16245A449 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 10/01/1979 |
| From: | Rolonda Jackson Office of Nuclear Reactor Regulation |
| To: | Fairtiler M Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16245A450 | List: |
| References | |
| NUDOCS 7910160445 | |
| Download: ML16245A449 (2) | |
Text
o UNITED STATES NUCLEAR REGULATORY COMMISSION o
WASHINGTON, 0. C. 20555 0
O CT 0 1 !979 MEMORANDUM FOR:
M. Fairtile, PM Operating Reactors Branch No. 4, DOR FROM:
Robert E. Jackson, Chief Geosciences Branch, OSS
SUBJECT:
EARTHQUAKE ACTIVITY AT JOCASSEE DAM GEOTECHNICAL ENGINEERING ASPECTS PLANT NAME: Oconee Nuclear Station/Jocassee Dam DOCKET NUMBERS:
50-269/270/287 TAC NUMBER:
5290 RESPONSIBLE BRANCH:
R-4; M. Fairtile On August 26, 1979 Duke Power Co.
informed I&E, NRC that a magnitude 3.6 earthquake occurred near Jocassee Dam. On August 27, 1979 Duke Power Co. informed ORPM of the event. The Oconee project manager, Mort Fairtile, then informed Robert Jackson, Chief, Geosciences Branch. On August 27, 1979, Dr. Phyllis.Sobel, a seismologist in the Geosciences Branch, called Dr. Pradeep Talwani of the University of South Carolina to confirm the reported earthquake. Dr. Talwani is.under USGS contract to monitor seismicity in the area of the Jocassee dam. A report on the earthquake is contained in the enclosed memorandum which describes seismicity near Lake Jocassee. On August 30, 1979 Dr. Sobel called Dr. Talwani to find out if there had been any aftershocks. Dr. Talwani reported about 15 aftershocks. He also informed Dr. Sobel that he had received unconfirmed reports of increased seepage from the dam since the earthquake. Consequently, on September 4, 1979, a conference call was made to Duke Power.
Participants were:
Stewart Lewis Duke Power Rod Shatnagar Duke Power Ernie Brockman Duke Power Dudley Stone Duke Power Clay Sams Law Engineering Testing Co.
Mort Fairtile NRC, OCR Robert Jackson NRC, GSB Leon Reiter NRC, GS8 Phyllis Sobel
- NRC, GSB Owen Thompson NRC, GSB 7 q1 0160
0 0
M. Fairtile
- 2 Duke and-Law told us that inspection of the.dam by Law Engineering Co. on August 31 and September 1, 1978 had been made by Clay Sams and George Sowers. Mr. Sams reported to us during the conference call that there were no adverse affects.such as cracking due to the earthquake. He reported that seepage remained normal considering rainfall, that the water was clear at the time of their inspection and that no cracking or other effects were noticed in the embankment.
He reported that the survey of settlement monuments was not complete although preliminary data indicated that any settlement due to the earthquakes was probably less than 0.75 inches. Some cracks were noted in the elevated floors of the Jocassee hydro-electric power house and the origin.of these cracks (primarily whether or not they were earthquake induced) was still under investigation because they could have existed prior to the earthquake.
Mr. Lewis informed us that within about a month we would receive a written report of the inspection.
We anti cipoate that the report." will reflect the opinion of the consultants that the earthquake has not affected the safety of the dam and thus we expect that no further evaluation of the earthquake effects on the dam by my geotechnical engineering staff will be needed.. We will confirm this following our review of the consultant's report.
The Jocassee Dam is regulated by the Federal.Energy Regulatory Corni:ssion (FERC) and we will continue to work through and with them in our evaluation.
We will continue our review of seismicity at the site as discussed in a memo from Dr. P. Sobel, Seismology Section, G-^3, to me dated A1-ugust 29, i1979; a copy of that memo is enclosed.
This geotechnical engineering review was prepared by Dr. Owen 0. Thompson, GES, GSB.
Robert E. Jack
, Chief Geosciences,3ranch, OSS
Enclosure:
As stated cc:
w/enclosure J. Knight R. Reid A. Cardone W. Gammill R. Jackson
- 0. Thomoson C. Murphy L. Heller Local POR R. Shewmaker, LE HQ L. Reiter POR F. Jape, U&E, Region I :. Sobel FERC ( H M
am j
H. Thomas