ML20114F318
| ML20114F318 | |
| Person / Time | |
|---|---|
| Site: | 05000214 |
| Issue date: | 05/04/1965 |
| From: | Spencer G LOS ANGELES DEPT. OF WATER & POWER |
| To: | |
| Shared Package | |
| ML093631134 | List:
|
| References | |
| 50-214-65-02, 50-214-65-2, NUDOCS 9210120438 | |
| Download: ML20114F318 (5) | |
Text
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U. S. ATOMIC ENERGY COMMISSION REGION V DIVISION OF COMPLIANCE May 4, 1965 CO REPORT NO. 214/65-2
Title:
DEPARNENT OF WATER & YOWER, CITY OF LOS ANGELES LICc!;SE NO. (Not Issued)
Data of Visit: April 30, 1"65 By:
G. S. Speccar. Retcest Inspector
SUMMARY
The proposed site of the City of Los Angeles Department of Water and Po'ser (LADWP) Malibu Nuclear Plent, located in Corral Canyon, Malibu, Cali.ornia was visited on April 30, 1965. The purpose of the - visit to observe the trench recently excavated.across the floor of the v: 5 canyon, at the request of the Atomic Safety & Licensing Board, and to interview the geologista present representing the U.S.G.S., the applicant and the intervenors, concerning their findings.
The excavation has revealed a geological feature variously interpreted as being either landslide or seismic in origin, depending on which geologist is quoted. The fauure traverses the trench at a location approximately 15 feet inside of the proposed outer perimeter of the reaccor st ructure.
Samples of the contained shell and carbon deposits are being carbon dated to determine the maxieum age of the movement which created the " feature".
DETAILS 1.
Scope of Visit The proposed site of the LADWP Malibu Nuclear Plant located in Corral Canyon, Malibu, California was visited by G. S. Spencer and R. H. Engelken, Region V, Division of Compliance. The visit included observation of trenches recently excavated across the floor of the canyon and on the south slope of the hill forming the east wall of the (Continued) 9210120438 920S20 PDR ORG NRCHIST PDR
i t Scope of Visit (continued) 4 canyon. The inspectors also interviewed geologists representing the U.S.G.S., the applicant and the intervenors concerning their findings.
Interviews were held with the following individuals.
R. Yerkes Geologist, U. S. Geological Survey T. L. Bailey Independent Consultaat Converse Foundation Engineers F. J. Converse G. E. Blanc Coordinator for Atomic Energy &
Radiation Protection, State of California II.
Results of Visit A.
_ Background In response to a request by the Atomic Safety and Licensing Board hearing the LADWP case, a trench was excavated across the floor of the Corral Canyon site to permit a more thorough evaluation of the site for evidence of seismic faulting. Additional trenches were dug on the south slope of the hill which forms the east wall of the canyon in an attempt a
to follow the trace of the Escondido Fault mentioned in Compliance Report No. 214/64-1. The trench excavations were completed and the site opened for inspection by representatives of all parties concerned on April 30.
According to LADWP, the trenches would remain open through May 2 after which time they would be backfilled.
B.
Description of Trenches 1.
Main Exploratory Trench The main exploratory trench across the floor of the canyon was observed to be excavated in a northeast - southwest orientation.
It appeared to be 25 feet wide at the surface, narrowing down to 6 feet at the Soctom. The trench followed the contour of the terrain and was approximately 25 feet deep throughout its length.
Station markers spaced five feet apart, were staked along the length of the trench.
At Station 17, approximately 15 feet inside of the pro-posed perimeter ok the reactor building, a geological feature, distinguished by lagoon oeposits-underlying older bedrock, was exposed in both walls and floor of the trench. This " feature" was observed to traverse (continued)
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Results of Visit (continued) 4
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the trench in a northwest - southeast orientation.
Judging.
l from the elevation indicated on the adjacent station -
j marker, the most prominent exposure of the. feature appeared -
at an elevation'of roughly 25 feet above mean low sea-level.
i-2.
Other Trenches l
Additional trenches were observed to be dug'on the south slope of the hill.which for.s the east vall of the canyon..
l According to the U.S.G.S. geologists, these hillside trenches were dug in'an-attempt to follow the trace of the Escondido Fault.
l C.
Geologists Present At Site I
At the time the ' inspectors arrived at the site, the following geologists were observed to be present.
l R. Yerkes U. S. Geological Survey i
l C. Wentworth U. S. Geological Survey-i T. L. Bailey
~ Independent Consultant (Intervenors) i.
Barkley Kamb Cal. Tech. (retained by-Intervenors) i' Benjamin Troxel Calif. Division of Mines & Geology George Cleveland
- Calif. Division of Mines & Geology l
F. J. Converse Converse Foundation Engineers Roy Hoffman j
J. L. Smith i
l B. Spellman i.-
1 Arden Albee Cal. Tech. (retained by Converse) f-R. H. Jahns' Dean of Mineral Sciences.. Penn.
j State University-
- W. K. Cloud, Geophysicist with the U. S. Coast & Geodetic Survey was also present, but stated that he was there merely'as'an observer.
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Results of Visit (continued) r f
D.
Interviews With Geologists Present 1.
Interview With R. Yerkes - USGS i
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Mr. Yerkes described the geological feature as lagoon l
deposits, consisting of sandstone and carbon from reedst i
or marsh grass, underlying a mach older stratum of; bedrock.
He stated that the only mechanisms by which this sort tof i-configuration could be formed would be either a landslide or a tectonic movement.
Yerkes estimated the agW of the younger, underlying stratum as 10,000 -100,000 years i-and the older overlying bedrock as 12,000,000 years. He j
said that samples of the contained'shell and carbon deposits are being analyzed for_ carbon-14 to determine the maximum age of the movement which created _this geologic feature, j
Yerkes also stated that he feels the evidence needed to j
' determine whether this feature represents-a landslide l
or a fault has not been exposed as yet and that further j
excavation would be required to trace. it out for a more
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conclusive finding.
2.
Interview With F. J. Converse - Converse -Foundation Engineers Converse Foundation Engineers of Pasadena, California is'
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under contract to LADWP and has conducted a geologic and soil condition study of the site,- including test borings.
Mr. Frederick J. Converse, President of the tira was L
present at the site and appear;d to be. actively parti-cipating in the study of the trench excavation.
Mr. Converse l
cold the inspectors that.his: people had not.found any l
new evidence which would_cause them to change-their j
original survey findings. He stated _ that-he believes the
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geologic feature in question was created'by an old l
stream which came through and undercut: this section, causing a cave-in or slide. He added that at least that l
was Converse Engineers' diagnosis of the situation.
j.
According to-Mr. Converse, the feature at this site is i
similar to other stream-cave. formations seen at other locations.
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3.
. Interview With T. L. Bailey - Independent Consultant,
Intervenor Dr. Bailey, an " independent. consultant" who has testified-j-
as an intervenor witness at the IADWP' construction permit 1
(continued) i
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i' Results of Visit -(continued)
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hearing : held in March 1965, was noted to be presentiat -
jl the site and was interviewed ~regarding his finding, Dr. Bailey stated:that it -is his: belief that the geologic feature uncovered by the trench ~is-more apt!to be-a fault rather than a landslide. He based -his belief on the contention that the rock and soil involved in a landslide movement would be rolled, but not crushed.
Bailey said that' the sheared, crushed and-broken nature i
of the area in general, as revealed by the trench l
excavation, indicates that this is the center of a fault
- zone, i.
Dr. Bailey also mentioned that the trenches-dug in the
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south slope of the' hill forming the east wall of the canyon-had'provided' additional interesting information-relative. to seismic. activity in_ the area of the site..He l
stated that terrace gravel (or slope soil) had been found l
at a depth of 45 feet. This phenomenon can_only be-l explained by postulating an earthquake which opened.upe l-the ground,: permitting the topLsoil;to dropfto the depth l-described, before reclosing. -Prior;to leaving the site, the inspectors viewed one of the hillside trenches mentioned L
by Bailey. Although some. variation could be seen-in-the soils located at the lower depth of the trench, none -
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of the other. geologists were present and, consequently, their j
comments were not obcained.
4.
Interview With G. E. Blanc - State of California -
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L Mr. Gene Blanc. Coordinator for Atomic Energy & Radiation l
Protection, State.of Calf fornia, was questioned regarding j
the findings made by the State geologists present.
Mr. Blanc stated that they had not seen anything they didn't l
. expect to see. He also indicated.that the State geologists l;
felt that many of the people.present-vere seeing what l
'they wanted to see. One of the State people, Benjamin l
Troxel, apparently was inclined to-interpret the geologic
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" feature" as landslide caused, i
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