ML19329A227
| ML19329A227 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 01/15/1976 |
| From: | Rolonda Jackson Office of Nuclear Reactor Regulation |
| To: | Gammill W Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19329A223 | List: |
| References | |
| NUDOCS 7912300268 | |
| Download: ML19329A227 (2) | |
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UNITED STATES
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JAN 1* jrc 5.3, William P. Cammill, Assistant Director j h J. C. Stepp, Chief, Geology and Seismology Branch j.7'-
for Site Technology TilRU:
SEISHIC EVEST SE/.R OCOSEE PLANTS 14, 1976 I had a telecon with Dr. Pradeep Taluani, a On January In the conver-seismolo;;ist at the University of South Carolina.
sation ha indicated that he was involved in monitoring some earth-quakes in the vicinity of Lake Jocassee, South Carolina, approxi-The mately 15 miles north of Oconee 1, 2, 3 nuclear plant.
chronology of his involvement is as follows:
Lake Jocassee began filling in 1973 and reached full head in At that time a earthquake was felt by one March 1975.
individual near the dam.
On October 1, 1975 a magnitude 3 earthquake was felt at the dem and Dr. Talwani states, "it shook up the people in the powerhouse." Two days after this event several small after-shocks were picked up with instruments.
Other events were noted on November 6 and 7 and monitoring was undertaken for 10 days af terwards, a large number of aftershocks were recorded.
On November 9, Law Engineering, consultants to Duke Power, set up instruments borrowed from Dr. Long and about this same time Dr. Talwani installed a six (6) station network in the area.
On November 25, 1975, a magnitude 3.2 earthquake was recorded This event pas felt over a large area.
at Lake Jocassee.
Dr. Taluani stated that in his analysis, the epicenters were Two hundred aftershocks progressing continually downward.(As per a later conversation w
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were recorded.
this event Region II, Office of Inspection and Enforcement, tripped a.s,eismic instrument located in the reactor tendon y
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- i Willian F. Gammill gallery. These instruments were set to trip at.Olg.
One Mr did trip and there has been some difficulty in getting the records analyzed due to closing of the company that supplied the instruments.)
. ' O:1 December 8, tuo or three shocks were felt ranging from magnitude 2.5-2.7.
Dr, Talwani also stated that there have been a number of other events of magnitude 2 or more.
In a inter telecon uith Bud Epps of Region II, Office of Inspection and Enforcement, he stated that h.e was aware of the early fall event, The former probably October 1,1975 and the November 25 carthquake.
was not fcit at the plant, the latter was discussed earlier. He has received ~ telephone communication on a number of occasions when earthquakes were noted at Lake Jocassee but only the November 25 shock caused the seismic instruments to be triggered.
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obert E. J,ackson, Geologist Geology an Seismology Branch Division I Site Safety and Environmental Analysis cc:
H. Denton G. Zech R. Jackson 4
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V William P. C=- H 1, Assistant Director for Site Technology l
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J. C. Stepp, Chief, Geology and Seismology B anch SEISMIC EVENT NEAR OCONEE PLANTS ~
On January 14, 1976 I had a telecon with Dr. Pradeep Talvani, a seismologist at the University of South Carolina.
In the conver-sation he indicated that he was involved in monitoring some earth-quakes in the. vicinity of Lake Jocassee, South Carolina, approxi-mately 15 miles north of Oconee 1, 2, 3 nuclear plant. The chrono 1c.ty of his involvement is as follows:
Lake Jocassee began filling in 1973 and reached full head in
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March 1975. At that time an earthquake was felt by one individual near the dam.
i On October 1, 1975 a magnitude 3 earthquake was felt at the dam and Dr. Talwani states, ','it shook up the people in the j
powerhouse." Two days after this event several small afterw
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shocks were picked up with instruments.
Other events were noted on November 6 and 7 a~t monitoring was undertaken for 10 days afterwards, a large w her of i
aftershocks were recorded.
On November 9, Law Engineering, consultants to Duke Power, set up instrunents borrowed from Dr. Long and about this same time Dr. Talwani installed a six (6) station network in the area.
On November 25, 1975, a magnitude 3.2 earthquake was recorded at Lake Jocassee. This event was felt over a large area.
Dr. Taiwani stated that in his analysis, the epicenters were progressing continually downuntd. Two hundred aftershocks were recorded.
(As per a later conversation with B. Epps of Region II, Office of Inspection and Enforcement, this event tripped a seismic instrument located in the reactor tendon 1,
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i gallery. These instruments were set to trip at.Olg.
One did trip and there has been some difficulty in getting the l
records analyzed due to closing of the company that supplied the instruments.)
g On December 8, two or three shocks were felt ranging from magnitude 2.5-2.7.
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Dr. Talwani also stated that there have been a number of other events of magnitude 2 or more.
t In a later telecon with Bud Eppe of Region II, Office of Inspection and Enforcement, he stated that he was aware of the early fall event,
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probably October 1,~ 1975 and the November 25 earthquake. The former was not.elt at the plant, the latter was discussed earlier. He has' received telephone communication on a number of occasions when.
earthquakes were coted at Lake Jocassee but only the November 25 shock caused the seismic instruments to be triggered.
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Robert E. Jack on. Geologist Geology and Seismology Branch Division of Site Safety and Environmental Analysis l
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H. Denton G. Zech DISTRIBUTION:
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