ML20198F820
| ML20198F820 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 07/18/1974 |
| From: | Cox T US ATOMIC ENERGY COMMISSION (AEC) |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| CON-WNP-0982, CON-WNP-982 NUDOCS 8605290106 | |
| Download: ML20198F820 (4) | |
Text
/
O
~
Q.
p $
~':.
J,...
~,.
s.-
- ~
\\
- '( ' :.".
.g 3 g
_._m.
.__.a.__.
s DOCKET NO. 50-460
- APPLICANT: WASHINGTON PUBLIC POWER SUPPLY SYSTEM (WPPSS)
FACILITY: WASHINGTON NUCLEAR ONE AND FOUR (WNP-1 AND -4)
~
I
SUMMARY
OF MEETING HELD TO DISCUSS NEW SITE I;E0 LOGY AND SEISMOLOGY On July 11, 1974, representatives of WPPSS, United Engineers and Con-structors (UE&C), their consultants and the Regulatory staff met in Bethesda, Maryland, to discuss geological and seismological studies conducted to support the selection of the new site. Foundation engineering work was not discussed at the meeting. The purpose was to inform the staff and exchange ideas and opinions prior to final preparation of Amendment No. 9 to the PSAR scheduled for submittal on August 15, 1974. An attendance list is enclosed. A summary of the meeting discussion follows.
Mr. Valentenyi (UE&C) began the presentation with a description of the WNP-1 and -4 geographic locations relative to existing Hanford structures, i
the AEC Fast Flux Test Facility, major highways and railroads and the Columbia River. He noted that the site area is at approximately the same elevation as the Hanford 1 site, and the containment and general services -
buildings will be placed within a few feet of the elevations formerly selected for the same structures at the Hanford 1 site.
Dr. Coobs (Weston Geophysical) briefly reviewed the geology of the site and described the significant features in the area surrounding the site. The potentially controlling geologic structure is the Rattlesnake-Wallula alignment, trending northwest-southeast and approaching within 13 miles of the site on the southwest. The applicant has selected a safe i
shutdown earthquake (SSE) of 0.25 g's acceleration at the foundations i
of the site structures.
Mr. Danchy (Fugro) gave a more detailed description of the structures l
-- investigated along the Rattlesnake-Wallula alignment, and showed preliminary draf ts of maps and section drawings to be included in the PSAR amendment.
The boreholes drilled on the site were described, as were stratigraphic cross-sections of the site area, drawn from data taken in the borings. It was stated that the Category I structures will be founded on the Ringgld formation material.
8605290106 740718 i
PDR ADOCK 05000460 A
d j
~
7 C.
10 QQ
.. ~
~
i Mr. Turcotte (Weston Geophysical) discussed the shallow and deep hole refraction line surveys done in the site area. Data was produced along four refraction lines bounding the entire WNP-1 and -4 site area. In addition, shorter refraction line surveys were made cressing the locations of the Category I structures at each of the WNP-1 and -4 locations.
Compressional velocities measured were in the 8000 to 10,000 f t/sec range, except for an area in the northeast corner of the site area which showed I
some lower velocities at depths of approximately 360 feet. All die velocities measured were indicative of acceptable mechanical properties of the site soils.
Responding to 'a question by the staff concerning data being collected by a microearthquake sensing network in the area, the applicant stated that there has not been any activity detected by the net which would have adverse implications on the seismological evaluation of the site or surrounding area.
On site trenches were described by Mr. Swanson (Fugro). A total of about 360 feet of trench,.several feet deep, was excavated in a T-shaped plan at each site. Detailed examination of'the trenches showed no disruption of cross bedding structures and no disruptien of the contact between the Pasco gravels and the Eolian sands. No clastic dikes were observed.
Mr. McMullen of the staff felt that a decision as to whether or not the trenches will be inspected by staff geologists should be made af ter -
studying the forthcoming PSAR amendment. All parties agreed to this.
At'the conclusion of the meeting, several topics of particular interest to the staff were noted for the applicant 'to consider during final preparation of the forthcoming PSAR amendment. These are summarized below:
A clear differentiation between the Ward Gap and Elephant mountain flows is needed in the site stratigraphy presentation.
The region of lower compressional and shear wave velocities should
+
be fully described and its effect on site foundation engineering thoroughly discussed.
The application and evaluation of data from the Hanford area
+
mic,roearthquake network to WNP-1 and -4 site seismological studies' should be carefully documented in the PSAR.
- A very thorough, cogent examination of the tectonic continuity of the structures along the Rattlesnake-Wallula alignment is necessary
+
o J
.s
/
'-x q -
1 pr s-,
..- y.
y
~
to justify the selected (maximum) safe shutdown earthquake and the resulting maximum postulated site acceleration.
i 4
~~@ 3taned by Thomas H. Cox, Project Manager Light Water Reactors Branch 2-3
Enclosure:
Directorate of Licensing Attendance list DISTRIBUTION:
Docket Piles AEC PDR LPDR L Reading LWR 2-3 Reading RP ads RP BCs SVarga DEisenhut JHendrie TR ads TR BCs THCox R0 (3)
RS (3)
DKartalia ACRS (16)
EGoulbourne l
f x7886/ LWR 2-:
.,,s. s,
.Tl* Col.hh
...n. s,
7/M/74
_,, Form ABC.)l4 (Rev. 9 53) ASCM 0240_
W u. s.oovsanusse paintine orrects tere.ese.see
?
s DOCKET 50-460 MEETINGWITHVASHINGTONPUBLICPOWERSUPPLYSY5 TEM WASHINGTON NUCLEAR ONE July 11, 1974 NAME ORGANIZATION T..H.
Cox AEC - DOL S. M. Copicn AEC - L R. McMullen AEC - L L. W. Heller AEC - L
- F. T. Turcotte WESTON GEOPHYSICAL E. A. Danchy FUGRO, INC.
O. E. Swanson FUCRO, INC.
T. F. Sexton WESTON GEOPHYSICAL Ryharavi wwess
- p..
w.
C. B. Organ WPPSS A. J. Friedenn UE&C D. D. Tillson WPPSS A. G. Hosler WPPSS G. E. Thornes UE&C G. Valentenyi UE&C Dr. H. A. Coombs WESTON (CONSULTANT)
4
.