ML19220B944
| ML19220B944 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 10/15/1975 |
| From: | Harold Denton Office of Nuclear Reactor Regulation |
| To: | Moore V Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7904270684 | |
| Download: ML19220B944 (3) | |
Text
..
COT 13 g3 Voss A. Moore, Assistant Director for Light Water Reactors, Group 2, RL DRAIT SER INPUT - GEOLOGY, SEIS>f0 LOGY, AND FOUNDATION ENGINEERING PLANT NAME: Three Mile Island Nuclear Station, Unit 2 LICENSING STAGE: OL DCCIET NUMBER: 50-320 MILESTONE NUMBER: 24-32 RJ.SPONSIBLE BRANC3: LWR 2-3 REQUESTED COMPLETION DATE: September 5, 1975 APPLICANT'S RESPONSE DATE NECESSARY FOR NEXT ACTION PLA.'CIED ON PROJECT: N/A DESCRIPTION OF RESPONSE: N/A REVIEW STATUS: N/A Our input to the SER on the geology, seismology, and foundation engineering, prepared by J. Skreve, R. Hof-ann, and L. Eeller, Site Analysis Branc.h, for the Three Mile Island Nuclear Station. Unit 2, follows:
h geology, seismology, and foundation engineering aspects of the Three Mile Island site were reviewed in detail at the Construction Permit stage of licensing for Unit 2.
N results of these reviews appear in our Safety Evaluation Report datsd September 5,1969.
Geology
.No further geologic information has been presented which would change the conclusions presented in the SER. h applicant has clarified the age of last covement along the Old Triassic Border Fault northwest of }'dddleton as being at least 695,000 years before present. There are no other out-standing issues in geology.
Seismology The Three Mile Island Nuclear Power Plant is within tha Pied =ont Provinca.
h Ridge and Valley Province bounds the Piad=ent to the northwest and the Coastal Plain Province to the southeast. h largest earthquaka in the Piadmcat Province is of MM Intensity VII, e.
g., December 18 and 19,1737 naar New York City. )H Intensity VII corresponds to a mean acceleration of.12g as graphed by Newmann, 1954. This is essentially the same value as that obtained from the m n curve of Trifunac and Brady, 1975.
Historical earthquakes in the Atlantic Coastal Plain have occurred in recognizable geographie clustars. One cluster in the vicinity of Charleston, South Carolina, is associated with the axis of Southeast ' rgia (Raritan) opeecu e
. ~. -
1 h
su.= a m e >
oevs >
Form AIC-318 (Rev. 9 $3) AECM 0240 W u. s. sovenmuswt enumme orricea vote.sas.ies 79042706M g
Voss A. Moore
- 2 CCT I 3 T3 embaYeant, although no specific geologic structure has been described there. This area la also the epicenter region of the }M Intensity X earthquake of 1836. Because of the correlation with the axis of the e=bayment and the spatial clustering exhibited by historical events (more than 400 quakes,in the Charlaston araa), we have accepted that futura earthquakes will also occur in the same region. Thus, an earthquake in the Coastal Plain Province is not expected to cause an intensity at the Three Mile Island site that will exceed an intensity of approximately VI to VII.
h max 1:xum earthquaka that has occurred in the Valley and Ridge Province was that in Giles County, Virginia of }H Intensity VIII, or an equivalent mean accelaration of.258 The sita is approximataly 10 miles frem the Valley ar.d Ridge Province and opposite the northern portion of the province which has aztre= sly lov seismicity. Consequently, the.12g of SSE is baliaved conservative.
That different parts of Eastern United States tectonic provinces have dif-farant levels of sarthquaka activity, although older geological features are similar within each, is demonstrated by the NOAA S41artic Risk Map.
The Three Mile Island Nuclear Power Plant site is within Zone 1, developed fron historical saicmf city, corresponding to )M Intensities of V and VI which in turn correspond to a icwar mean acceleration than the SSE used.
No in:tornatien has been discovered aface the PSAR reviav for the Construction Permit to altar earlier conclusions or to indicata the site area has been shaken at a greater 1H Intsnaity than IV (equivalent maan acceleration of about.017g). Consequently, we find an SSE of.12g and au OBE of
.06g acceptable.
Foundation Engineering h adequacy of the safety-related foundations and design criteria for buried pipelines was reviaved at the Construction Pertit stage by the U. S. Geological Surysy and N. M. Newmark, Consulting Engineering Service and found to be acceptable (see SER for Unit 2 dated September 5,1969 and SER for Unit 1 dated July 11, 1973).
In the FSAR for Unit 2, the applicant has analytically demonstrated the ability of the foundation rock to support safety-related structures.
Ha has also demonstrated that a plausible failure of the slope of the earthen dika in the vicinity of the essential river water intake structures would would not result in a blockage of the pump 1 stakes by slope dabris.
.~.
g q.'120 su==4=s*
3 A YI M Form AIC.318 (Rev. M)) AICM 0244 2 u. s. eovannassut painvine orrican ion.eae.s ee
h Voss A. Moore 3 -
CCI 15 G75 We conclude that thers are no as-built foundation or slope stability hazards associated with the safe operation and/or shutdova of the Bras Mile Island Nuclear Power Plant.
n <.i r w m _ i; m
F'
,Earold R. Denton, Assistant Director for Site Safety Division of Technical Review Office of Nuclear Reactor Regulation ec:
R. Boyd W. Mcdonald J. Panzarella S. Hr.nauer R. Reineman SS Branch Chiefs B. Danton D. Crutchfield A. Schwencer L. Engle A. Cardone R. Klackar De Eis chut M. W1111mm.
S. Varga L. Hallar J. Stapp J. Skrove R. Hofmnn Distribution:
Central Files NRR/?cading File SAB/ Reading File 84~121
\\
f oe. e n +
c.
,)b TR SAB TR:S TK: AS TR:SA3d(Q7 TR:
B_
TR:.qfS g.
r t g,,
s J.SkrovIN_
R.Eofdann__
J.
epp.._.
L. Heller W.G 11g'q _H. De,pt o n 10 -f d
-75 10- Q --75 10- / 7 -75 10- /[-75 10
- 0
-75 10... 7
-75 f
Q AT, %
4-Forum AIC 318 ( Re. 9-5 3) AECd 02 40 2 u. e. oov a nnes sier esinvime oewic as s e re.sse-s ee