ML19209A134
| ML19209A134 | |
| Person / Time | |
|---|---|
| Site: | Vallecitos File:GEH Hitachi icon.png |
| Issue date: | 09/13/1979 |
| From: | Nelson C Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7910020608 | |
| Download: ML19209A134 (50) | |
Text
-
pn ne.m UNITED STATES y i 3m g
NUCLEAR REGULATORY COMMISSION 2 p{... j WASHINGTO N. D. C. 20555
(
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September 13, 1979 Docket No. 50-70 LICENSEE: GENERAL ELECTRIC COMPANY (GE)
FACILITY: GENERAL ELECTRIC TEST REACTOR (GETR)
SUBJECT:
SUMMARY
OF MEETING HELD ON AUGUST 22, 1979 REGARDING NRC STAFF REVIEW 0F THE GETR SEISMIC CONCERNS At the request of GE, a meeting was held regarding the review schedule for the GETR show cause proceeding. A list of attendees is attached as.
GE surmarized the key events of the GETR review to date. This sumary is attached as Enclosure 2.
GE noted, in particular, the following items:
1.
GE Probability Analysis, submitted April 27, 1979, presented a conservative but realistic argument.
2.
The August 1979 evaluation of GETR by the California Division of Mines and Geology (CDMG), a copy of which was supplied by GE and is included as Enclosure 3, corroborated GE's position regarding the Verona Fault.
3.
The recently issued USGS report, " Flatland deposits of the San Francisco Say Region, California - their geology and engineering properties, and their importance to compre-hensive clanning", does not mention the Los Positas or Verona Faults and snould be considered in the NRC staff's safety evaluation.
.t. GE ex;;ressed ccncern that the NRC staff's safety evaluation would not :e issued in August 1979 as had been estimated in the NRC's letter of June 8, 1979. 5upporting this concern, GE noted the NRC staff's request of August 16, 1979 for engineering infomation and the lack of USGS final input to the NRC. GE noted that, of the remaining actions, the issuance of the staff's safety evaluation was the most important. GE requested that this action be expedited.
GE also presented a " Listing of Submittals Made to the NRC" which is included as Enclosure 4.
l~l36 177 niooe o go?
A
GETR.
In response to GE's coments, the NRC staff confirmed that its safety evaluation would not be issued in August. The staff stated it excects to issue that portion of its evaluation regarding geology and seismology in September and the balance of the evaluation folicwing receipt and review of the outstanding engineering requests of June, July and August.
The NRC staff noted that t'he USGS had been very responsive throughout the GETR review and stated that USGS input to the staff's evaluation was expected within about a week. This input would address the recent USGS report noted by GE.
Following the meeting, W. Andrew Saldwin.of Friends of the Earth, a party to the GETR show cause proceeding, arrived and was briefed regarding the content of the meeting.
d Chris Nelson, Project Manager Operating Reactors Branch #4 Division of Operating Reactors
Enclosures:
1.
List of Attendees 2.
Key Events of GETR Review 3.
CDMG Evaluation 4.
Listing of Submittals to NRC by GE cc w/ enclosures:
See attached page
Enclosure 1.,
GETR MEETING LIST OF ATTENDEES 8/22/79 Name Organizatic, L. Gossick NRC/EDO E. Case NRC/NRR S. Treby NRC/CELD
- 0. Swanson NRC/CELD W. Gammill NRC/NRR/COR W. Burkhardt NRC/NMSS C. Nelson NRC/NRR/COR
- d. Stone GE R. SecKer GE Rost Meetine Briefine W. Gammill NRC/NRR/ DOR C. Nelson NRC/NRR/COR W. Baldwin FRIENDS OF THE EARTH 1136 179
PURPOSE REVIEV KEY EVENTS SINCE LAST MEETING (7/11/78)
DISCUSS REMAINING ISSUES / ACTIONS
=
URGE E)PEDITIOUS ACTION 1136 180' 8753N9
KEY EVENTS GETR SHUTDOWN 10/27/77 SHOW CAUSE ORDER WHAT ARE 3EISMIC AND GEOLOGIC DESIGN BASES SHOW STRUCTURAL ADEQUACY OF GETR JUNE 2,1978 - STRUCTURAL ANALYSIS REPORT ADEQUACY OF CONCRETE STRUCTURE JULY 20,1978 - STRUCTURAL ANALYSIS REPORT ADEQUACY OF MODIFICATIONS JULY 1978 MEETING WITH L. GOSSICK, H. DENTON, ET AL REVIEW STATUS REQUEST EXPEDITIQUS ACTION FEBRUARY 28, 1979, FINAL GE0 LOGY INVESTIGATION REPORT SUBMITTED TO NRC MAY 31, 1973, R. BEATON LETTER REQUESTING ACTION JULY 8, 1979, REID LETTER COMMITMENT FOR SAFETY EVALUATION REPORT AUGUST 1979 Q,.. w.*4
\\\\36 I 22 7.ONTHS OF EFFORT STILL NO SER HES - 2 8/22/79
l' SAFETY EVALUATION REPORT SCHEDULE i
a AUGUST 1979 NRC COMMITMENT MAY BE IN TWO PARTS GE0 LOGICAL
~~
STRUCTURAL CONCERNED WON'T MAKE SCHEDULE CANNOT OBTAIN FIRM MILESTONES SUPPORTING AUGUST DATE l
GEOLOGIC DATA STILL COMING TO NRC (JACKSON) FROM USGS LATEST ROUNDS OF STRUCTVRAL QUESTIONS GOOD QUESTIONS, BUT LATE (REPORTS SUBMITTED MID-1978)
NEED NRC MANAGEMENT COMMITMENT l,
TOCOMPLETESERANDOTHERACTIONSl ses - 3 8/22/79
~
.1l36 182
KEY EVENTS (SINCE JULY IL 1978 MEETING)
SUBSTANTIAL ADDITIONAL GEOLOGIC INVESTIGATIONS GE0 LOGIC INVESTIGATION REPORT (SUBMITTED TO NRC 2/28/79)
GEOLOGIC QUESTIONS AND ANSWERS ON REPORT - COMPLETE 6/25/79 STRUCTURAL ANALYSIS QUESTIONS AND ANSWERS LATEST QUESTIONS RECEIVED 8/10/79 (TELECOPY)
GE PROBABILITY STUDY - TO NRC 4/13/79 USGS PROFESSIONAL PAPER 943 - TO NRC 7/12/79 CALIFORNIA DIVISION OF MINES AND GEOLOGY REPORT TO NRC AUGUST 1979
\\\\36 I GREAT DEAL OF GEOLOGIC SEISMIC WORK MUCH STRUCTURAL ANALYSIS ADDITIONAL PROBASILISTIC STUDIES MANY CONSULTANTS HES - 4 8/22/79
~
PROPOSED SEISMIC CRITERIA FOR GETR (50MW TEST REACTOR) SUBMITTED TO NRC JAN 6, 1978
'cFFECTIVE PEAK GROUND ACCELERATION - 0.6s (REG. GUIDE 1.6 SPECTRAL SHAPE)
OFFSET 1 METER ALONG SHEAR COMBINATIONS 0.la/1 METER OFFSET 0.4e/ZERO OFFSET e
a.
.~
s,, _ 3 7 7 s 6
,22/79 8/
7 134
i KEY EVENTS POSITIONS BY GE ( SUPPORTED BY EARTH SCIENCES ASSOCIATES AND ENGINEERING DECISION ANALYSIS CO. INC.)
LANDSLIDE MOST LIKELY CAUSE OF OBSERVED SHEARS CANNOT ABSOLUTELY RULE OUT TECTONIC (EAP.THQUAKE)
ORIGIN OF SHEARS f
SHEAR ZONE LENGTH LIMITED TO 8.2xM ASSUMING TECTONIC ORIGIN - DESIGN CRITERIA VERY CONSERVATIVE 1 METER OFFSET MAXIMUM EFFECTIVE PEAK GROUND ACCELERATION 0.8 G DUE TO CALAVERAS EARTHQUAKE (7 - 7.5 RIC! ITER SCALE)
LESS THAN 10-6/ YEAR PROBABILITY NEXT OFFSET UNDER REACTOR NO REQUIREMENT FOR DESIGN BASIS (NRC STD REVIEW PLAN FOR POWER PLANTS-SEPT.1975)
\\\\56
\\8S f " ~ ^ w,,4.
USE JF THESE VALUES MORE CONSERVATIVE THAN PROPOSED SEISMIC CRITERIA BASED ON THOROUGH INVESTIGATIONS g
VALUES USED IN STRUCTURAL ANALYSIS HES - 5 8/22/79
mm-m--
KEY EVENTS GE PROBABILISTIC STUDY (LIKELIHOOD OF SURFACE RUPTURE UNDER REACTOR)
CRITERIA:
USNRC STANDARD REVIEW PLAN FOR NUCLEAR POWER PLANTS PROBABILITY OF GCCURRENCE MROXIPATELY 1(y6/ YEAR OR LESS NO REQUIREMENT FOR DESIGN BASIS PROBABILITY OF OC URRENCE UNDER REACTOR WEIGHTED ESTIMATF: 4.5 x 10-7/ YEAR 95% PROBABILITY: a 1 x 10-6/ YEAR CONSERVATIVE ASSUMPTIONS PROBABILISTICS, A SOUND TECHNOLOGY THERE IS NO BLACK AND WHITE FORMULA FOR SPECIFIC INPUT SOME ENGINEERING JUDGMENT REQUIRED FOR CONSERVATIVE BUT REALISTIC VALUES PROBABILITY STUDIES, COMULTANTS AND STRUCTURAL EXPERTS CAN HELP IN ESTABLISHING REALISTIC ~ DESIGN BASES PROBABILISTICS A GOOD TECHNOLOGICAL TOOL 4,
j 1136 186 HES - 7 8/22/79
ADDITIONAL INFORMATION CALIFORNIA DIVISION OF MINES & GEOLOGY REPORT (GEOLOGIC EVALUATION OF GENERAL ELECTRIC TEST REACTOR SITE AT VALLECITOS, ALAMEDA COUNTY-SALEM RICE, ELGAR STEPHENS, CHARLES REAL)
EVALUATION OP VALLECITOS SITE GE0 LOGY LANDSLIDE MOST LIKELY EXPLANATION OF OBSERVED DATA CANNOT COMPLETELY RULE OUT TECTONIC ORIGIN CORROBORATES GENERAL ELECTRIC'S POSITION
)g
)g7 INDEPENDENT CALIFORNIA DIVISION OF MINES AND GEOLOGY CORROBORATES GE POSITION SHOULD BE CONSIDERED s tere: M, e- -
~.
HES - 8 8/22/79
ADDITIONAL INFORMATION O
PERTINENT UNITED STATES GE0 LOGICAL SURVEY REPORTS / PAPERS PROFESSIONAL PAPER WITH THOROUGH PEER / MANAGEMENT REVIEW (FLATLAND DEPOSITS - THEIR GEOLOGY AND ENGINEERING PROPERTIES AND THEIR IMPORTANCE TO COMPREHENSIVE PLANNING, E. J. HELLEY, K. R. LAJOIE, USGS: W.E.
SPANGLE, M. L. BLAIR, WILLIAM SPANGLE & ASSOCIATES,
1979)
STUDY OF QUATERNARY (YOUNG) DEPOSITS SAME TIME FRAME AS AUGUST 1977 REPORT SAME AGENCY AS AUGUST 1977 REPORT dADE AVAILABLE TO NRC NO MENTION OF LOS POSITAS OR VERONA FAULTS RECENT ADDITIONAL INPUT TO NRC SHOULD BE CONSIDERED M
swA II36 188 HES - 9 8/22/79
MODIFICATIONS TO GETR DESIGN OF MODIFICATIONS BASED ON VERY CONSERVATIVE CRITERIA 0.8a EFFECTIVE PEAK GROUND ACCELERATION 1 METER SURFACE OFFSET VIRTUALLY COMPLETE EXCEPT FCEL FLOODING SYSTEM FLOODING SYSTEM TO BE COMPLETED PRIOR TO STARTUP QA VERIFICATION BY NRC - ONGOING 1136 189 h=^ ".' t EXTENSIVE STRUCTURAL MODIFICATIONS HAVE BEEN MADE DESIGN CRITERIA MET g
HEs - 10 8/22/79
REMAINING ISSUES / ACTIONS PRESENT ISSUES FOR NRC:
SEISMIC DESIGN VALUE FROM CALAVERAS FAULT SEISMIC DESIGN VALUE FROM POSTULATED VERONA FAULT REALISTIC DESIGN SURFACE OFFSET VALUE POSTULATED LOCATION OF 0FFSET ISSUANCE OF SAFETY EVALUATION REPORT CONSERVATIVE BUT REALISTIC SCHEDULE ADVISORY COMMITTEE ON R'EACTOR SAFEGUARDS REVIEW ATOMIC SAFETY & LICENSING BOARD HEARING REALISTIC SAFETY EVALUATION REPORT M
- h...._T
- MOST IMPORTANT MILESTONE l-l 3 90 r'*
IMPORTANT ACTIONS REMAIN ALL MUST BE EXPEDITED HES - 11 8/22/79
GETR STATUS,
SHUT DOWN 22 MONTHS IMPORTANT FUEL TESTING ASSIGNED TO OVERSEAS AGENCY TIME CONSUMING EXPENSIVE SERIOUS LOSS OF QUALIFIED OPERATIONAL PERSONNEL ADVERSE IMPACT FUEL TESTING MEDICAL /CO MERCIAL ISOT0PE USERS EMPLOYMENT FOREIGN EXCHANGE g)
,%r
~g HES - 12 8/22/79
SUMMARY
EXPENDED LARGE EFFORT TO ASSIST IN ESTABLISHING CONSERVATIVE DESIGN BASES
~.
COMPLETED ADDITIONAL GEOLOGIC INVESTIGATION ESTABLISHED CONSERVATIVE VALUES FOR SEISMIC PARAMETERS MODIFIED FACILITIES TO MEET CONSERVATIVE DESIGN CRITERIA INDEPENDENT AGENCY CORROBORATED GE POSITION s
NEED PROMPT REALISTIC RESOLUTION e r e ::: 4 a
H36 197 HES - 13 8/22/79
RECENT AREA EARTHQUAKES
.DATE DISTANCE MAGNITUDE GREENVILLE 6/20/77 11 MILES 4.6 CALAVERAS 8/6/79 40 MILES 5.5 - 6.0 GETR SEISMIC INSTRUMENTATION
+
RECORDINGSEISMOGRAPH
=
~'
SEISMIC SWITCHES
+
GETR ACCELERATION VALUES (MAXIMUM)
GREENVILLE 0.05s CALAVERAS 0.02s GETR ACCELERATION (CALAVERAS) WITHIN lI36 I93 g.g;w. q":,lg EXPECTED VALUES NO SURPRISE O
HES - 14 8/22/79
PREPRINT 4
SPECIAL PUBLICAT!0ft 56 GEOLOGIC EVALUATI0fi 0F THE GEiiERAL ELECTRIC TEST REACTOR SITE VALLECITOS, ALAMEDA COU!iTY, CALIFORiilA By l
Salem Rice 2
Elgar Stephens Charles Real August, 1979 CAJORflIA DIVISI0ft OF MIliES AfiD GEOLOGY Rescurces Building, Rocm 1341 1416 flinth Street, Sacramento 95814
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~
1.
Geologist, San Francisco District Office, CCf4G 2.
Geologist, Sacramento District Office, CCf'G 3.
Seismologist, Sacramento District Office, CCf4G ll36 194 n
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~_
PURPOSE OF THIS REPORT The purpose of this report is to provide an outline of the California
' Division of Mines and Geology (CDMG) co'nclusions regarding the site geology of the General Electric Test Reactor (GETR) facility at Vallecitos, alameda County, California.
This report incorporates the staff observations and core,lusions which have been developed over a period of approximately two years. The CDMG staff have provided oral cer=entary to the U.S. Nuclear Regulatory Comis 1.a (!!RC) and the U.S. Geological Survey (USGS) at various tdmes during this period.
This report surm:arizes the siting implications of the staff analysis; see Section V, " Interpretation of Evidence for Design Criteria".
It outlines only the elements of the geology which are, in th, opinion of the staff, pertinent to the development of design criteria for the reactor.
The general geology of the area is presented in the Earth Sciences Associates (ESA) reports 1978-A and 1979, and the work of Herd (1977). Hall (1958), Jahns (1979), Rogers (1966) and others; see Section VI, " References".
The geologic observations that were made in the course of-the staff analysis described a number of low angle thrust displacements cf sedimentary materials in this portion of tne allecitos Valley.
In this report the comparison of evidence for a landslide origin as compared with the tectonic genesis of these features is considered. The displacements are referred to as faults regardless of interpretation of mechanism of origin.
lil36 195
'M
CONTEllTS Page i
Purpos e o f t h i s re po rt.............................................
1 I.
Background i n fo rma t i o n and s uw.a ry................................ 1 II.
Evidence of faults exposed in the trenches................'.........
8
^
Trenches T-1. T-2', B-1, and B-3.................................
8 Conclusions.................................................
10 Trenches 0-2 and 36 backhoe trenches lateral to it............
11 Conclusions.................................................
11 Tren ch es H, H-1, a nd H-2....................................... 11 Conclusions.................................................
12 Trenc he s A, A-1, a nd A-2....................................... 12 Co n c l u s i o n s................................................. 13 T re n c h E....................................................... 1 3 Co n c l u s i o n s................................................
1 3 D i s c u s s i o n..................................................... 14 III. Ori g i n o f th e fa u1 t s.............................................. 16 Arguments for and against tectonic faulting.................... 16 Arguments for and against landsliding........................... la Evaluation of evidence.........................................
20 IV. Significance of fault vs. landslide origin of the fault in tems of geol ogi c hazard to the si t e..................................... 20 V.
Interpretation of the evidence for design criteria................
22 Ground motion to be expected at the GETR site.................. 25 VI.
References........................................................
27 TABLES Table 1 -- Characteristics of thrusts exposed in the trenches.....
9 F1GURES Figure 1 -- Index map to the GETR site............................
2 Figure 2 -- Cemposite of faults mapped near the GETR site.........
3 Figure 3 -- Location of thrust faults in relation to GETR.........
4 Figure 4 - Cross-section of the GETR site shewing position of the reactor relative to faults 1 and 2.....................
5.
O 36 19()
Figure 5 -- Cross-secticn of the GETR site, shewing hypothetical landslide and thrust faul t slip surfaces..............
6 Figure 6 -- Tcpegraphy of the GETR vicinity shcwing pcstulated l a n d s 1 i d o s............................................ 15 Figure 7 -- Schematic diagram shewing relationship of late Quat-ernary sc il s and sediments at GETR si te............... 23
1.
Geologic Evaluation of the General Electric Test Reactor Site at Vallecitos, Alameda County 4
By
~
Salem Rice Elgar Stephens Charles Real California Division of Mines and Geologf I BACKGROU?ID TNFurftATI0rt AND Stfr7ARY The GETR is a 50 MW thermal test reactor used primarily for the produc-tion of radioisotopes for etedical diagnosis and therapy and for in J.,crial purposes. One of the first cc.mercial reactors in the United States, it was originally licensed in 1959, and is currently up for renew:31 of operating license.
Because of the recent issuance of a geologic map (Herd,1977) that shows a potentially active fault (the Verona) passing within a few hundred feet of the reactor, the NRC suspended operations of the GETR in October 1977 pending studies and hearings.
Since that time, extensive bulldozer and backhoe trenenfng in the vicinity of the GETR has revealed at least three, but perhap~ four er racre northwest-s trending low angle, thrust faults that bracket the reactor site (Figure 3).
All of these thrusts displace Plio-Pleistocene Livermore Gravels, and also displace Pleistocene colluvium and paleosols that overlie the Livermore.
Scme displace younger colluvium and soils of possible early Holocene age.
Given their attitudes, evidence of displacements, and relations to local topographic features, there are at least two plausible explanations for the origin ';f the thrust faults exposed in the trenches. These are:
- 1) tectonic thrust faulting, and 2) large scale landsliding (see Figure 5).
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Figure 4: Cross section of GETR site showing position of the reactor relative to faults 1 and 2, exposed in trenches B-1/B-3 and B-2, respectively.
Dips of thrusts are not known to depths indicated, but angles indicate n
average dips in trench exposures.
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L Evidence exposed in the various trenches, as well as the regional and local geologic and topographic settings, is discussed and illustrated in con-siderable detail by Earth Sciences Associates, the principal geologic consultants to General Electric Company, in their February 1979 report (ESA,1979).
In that report they discuss arguments for and against both landslide and tectonic origins for the thrusts (pp. IV 1-10), and conclude, "...we believe that the IMlide
. hypothesis remains the more reasonable, if not, conclusive, explanation."
(p. IV-1).
R.H. Jahns, another geologic consultant, to G.E., reached a similar conclusion (Jahns, 1979).
Informal ccamunications indicate that NRC advisors (the U.S. Geological Survey and David B. Slemens) may favor a tectonic origin for the thrusts.
In a CCMG memorandum to T.E. Gay Jr. on December 22, 1977, Rice Hart, and Kilbourne outlined the initial interpretations of Quaternary tectonic faulting in the area. The conclusion was expressed that the features observed to that date could have been caused by large scale landslide phonemena.
That judgment was heavily influenced by the interpretation frem air photos that topographic features of the southwest slopes of the ridge just north of the GETR were caused by massive slope failure to th> scuthwest. Low angle thrust faults exposed in Trenches T-1 and T-2 were interpreted as likely to be the sole thrust at the toe of the massive slope failure.
Since that initial CCMG evaluation, trench series designated A, B, D E,
F, G, and H were excavated by General Electric Compary in response to requests frca the NRC. The B and H series trenches exposed much mere evidence of. thrust displacements that have occurred in the vicinity of the GETR during late The other trenches revealed limited or negative ev :d r3e,t1 b 203 Quaternary time.
regarding these thrusts or their origin.
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Although exploration to date has not yielded conclusive evidence in favor of one or another origin of the faults observed in the T, B, and H series trenches, it is still our judgment, based on available evidence, that the observed thrust features probably were caused by large scale landsliding.
Our calculations (see page 20) indicate that without seismic influence, these landslide masses are stable under present climatic conditions.
- However, calculations also indicate that the upper landslide mass, above fault 1 (Figure 3),
could be activated by an earthquake generating an acceleration greater than 0.3g ct the sit'.; and that the landslide mass above fault 2 (Figure 3) ceuld be activated by an acceleration of about 0.6g. Amounts of displacements to be expected by such seismic reactivation along these slip surfaces shculd be on the order of a few feet per event.
We conclude there is no ev,idence that a fault intersects the GETR foundation; conversely, there is good evidence frem exposures in Trench B-1 that such a condition dces not exist.
II EVIDENCE OF FAULTS EXPOSED IN THE TRENCHES Trenches T-1. T-2, B-1, and B-3 The principal zone of thrusts intersects the surface in the immediate vicinity of the relatively sharp break in slope at the base of the ridge north of the reactor The GETR is abcut 400 feet frcm this break in sicpe.
All fcur trenches (T-1, T-2, B-1, and B-3 see Figure 3) along this :ene exposed lcw angle thrust faults dipping northeast (into the ridge). These trenches are-distributed along the break in slope frem abcut 3400 feet scuth-east of the GETR to 54C0 feet northwest of it, and the presence of similar thrusts in each strcngly suggests centinuity of displacement alcng this zone.
This thrust fault 2:ne, referred to in this repcrt as fault 1, correspends to Herd's Verena fault (Herd, 1977).
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E TABLE 1 CllARACTERISTICS OF TilRUSTS EXPOSED IN Tile TRENCllES LD Cencral Principal thrust Associated thrusts O
Total neparent Trench locatton C 3 displacement, number of thrusts Haterints displaced and comments u='
St -Ike Dip Strike Dip l
.~
T-1 At base of H LT 10 NE EW i 0-20 N Livermore Gravels Offsets Livermore Gravels sult 1 main ridge.
Older colluvium
"~nt least a few 10's of fe.
3400 ft. ESE Paleo-B perhaps as much as 100 It of CETR Stone line equivalent 7 or so (based on general i
identify fault appenrnnce).
T-2 Base of main Principal thrust Hany thrusts, complex, Livermot e Gravels ridge, 5400 not identified chaotic, highly older colluvium ft. NW of varin'ble in attitude, Paleo-B (7)
CETR but mainly low angle Fault 1 dips.
Bedding I
chaotically disturbed over a distance of at a'
l on e 107 fr_
B-1 Base of main H 30 W 0-15 NE NW 10-35 NE Livermore Gravels -----
> 40 feet ridge, 420 (concave (Imbrica-Older colluvium I
it. N of upward) f.lons of Paleo-D --------
-=--
B-10 feet CETR Fault 1 main thrust)
Stone line equivalent--
about 2 feet B-3 Base of main 13-20 NE N 60 W 10-15 NE Livermore Gravels ----
> 28 feet ridge, 450 Older colluvium ft. E of Paleo-B---------
10-11 feet i
CET R Fault 1 Stone line-------------
~ 2 feet
~
B-2 1300 ft. SW H 35 W 15-30 NE N 40 W 35 NE Livermore Gravels
> D0 feet of base of Older colluvium main ridge, Paleo-U 6 feet 1050 ft. SW Stone line sv 3 f eet
=---------
of CEIllrnni/j 11 2400 ft. SW H 85 W 10-25 NE None noted I.tvermore Gravels Offsets 1.tvermore g vels 11 - 1 of base of Older colluvium at least about 30 ft'. oc H main ridge, Paleo-B (several) haps much more.
A't,1 ea s t 2400 ft.
(No surf ace soils in 11) palcosols present liel ow
~,
~ SSW of CETR Adjacent 11 1 and 112 indicate thrust. k'cIl cy predsed Fault 3 probable displacements of sticks striklop. N }-40 E.
stone line by n foot or so)
{
(
Dips of the thrusts exposed in these trenches are icw, mostly 10 to 20 degrees. Abandant slickensides indicate predominantly dip slip displace-ments, with components of oblique movement being minor where present.
In all of these exposures. Livermore Gravels are thrust over older colluvium and paleosols.
In at least some (B-T and B-3) the stoneline, probably 10,000 to 20,000 years old} is offset up to about 2 feet. The swelling nature of the overlying surface soil dees not preserve displacement evidence, and there is no specific topographic evidence where these th' rusts project to the surface.
A well developed paleosol in these trenches is' displaced up to 10 or 11 feet, perhaps more. Apparent truncation or dissipation upward of seme of the thrusts that displace this paleosol in these four trenches suggests that multiple events may have occurred to accumulate its total displacement.
According to Shlemon (1979A, p. A-16), this paleosol probably formed 70,000 to 125,000 years ago. Maximum displacements of the oldest unit, the Livermore Gravels, is indeterminate because of lack of identifiable offset horizons in these tranches. However, it is certainly greater than about 40 feet.
Several paleosol horizons in Trench B-3 indicate that the older of the colluvial deposits over which the Livermore Gravels are thrust range in age from at least abcut 70,C00 to perhaps 350,000 yeafs (Shlemen, 197g8, p. B-16).
Conclusion Similarity of topographic positions and angles of dip of the faults exposed in these four trenches strongly suggest one zone of low angle thrust faulting (fault 1 of this report) between them along the base of the ridge.
The probable range of displacement cents on this fault is early Holocene (younger than about 9,CCO years) to more than 125,000 years. There have been at least two displacement events within about the last 70,000 years, but probably more.
g
\\\\b Shlemen,19793.
n,,n
11 Trench B-2 and 36 backhoe trenches lateral to it A second thrust zone, which dips 15 to 30 degrees northeast, is exposed in bulldozer Trench B-2 and in 12 of the 36 backhoe trenches lateral to it, he a known length of more than 1200 feet (see Figure 3). This thrust, fault 2 of this report, intersects the surface about 1350 feet southwest of fault 1, and is approximately parallel to the latter over its explore length. Fault 2 displaces the stoneline underlying the modern soil about 3 feet. An underlying 70,000 year old paleosol is displaced about 6 feet, and the Livermore Gravels are thrust a minimum of about 80 feet over alluvium-colluvium along this fault.
Some 1200 feet northwest of B-2, and en the strike of the thrust exposed in it, there is a low angle thrust exposed in several shallow backhoe trenches (fault 2A on Figure 3). This thrust appears to be arcuate to the northeast in trend.
It cuts Livermore Gravels, but does not displace the stoneline horizon underlying the youngest colluvium and soils. Thus it is not likely to be continuous with the fault 2 in Trench B-2.
Conclusion l,
Two separate faults are exposed in the B-2 group of trenches.
Fault 2 is similar to fault 1 in its range in age of displacements, and in its evidence of two or more displacements during the last 70,0C0 years, the youngest probably since abcut 9,000 years ago.
Fault 2A has not been active since formation of the stoneline horizon, estimated to be 9,0C0 to abcut 20,000 years old.
I136 207 Trenches H, H-1, and H-2 Abcut 2 00 feet southwest cf the base of the main ridge, a lcw angle, ncrtheast dipping thrust (fault 3 en Figure 3) is expcsed in bulldo:er Trenei H and in nearby backhee Trenches H-1 and H-2.
For its ex;csed length of ke-ei. abqgst 200 feet it has a ncrthwest strike.
In H, this thrust dips 10 to
12 degrees northeast and has wall defined dip slip slickensides where Livermore Gravels are thrust over :ollusium-alluvium a minimum of about 30 feet.
Several
. paleosols are certainly displaced in these trenches, but the amounts of these displacements are not apparent. Because of surface creep, plewing, and other human related 4c:
-ties, a definite determination cannot be made as to whether or not the surface colluvium has been displaced.
However, exposures in backhoe Trenches H-1 and H-2, the stoneline horizon appears to have been displaced a foot or so.
Conclusien Although details of amounts of displacements of paleesels are not apparent in the H trenches, the gross appearance of fault 3, and its df splacement chart.cter-istics, is similar to that of faults 1 and 2.
Trenches A A-1, and A-2 (See Figure 2 for location)
One of the argume.nts in favor of a tectonic origin for the thrust features exposed in the T B, and H trench series is that the upper member of the Liver-more Gravels just north of the GETR is very thick ccmpared te that about 2 miles along strike to the east.
Based on ESA's geologic mapping, thinning of this unit could amoant to as much as 4,000 feet over that distance. This ancmaly could be accounted for by faulting or by relatively abrupt stratigraphic thinning toward the edge of the 'casin of deposition.
Such an abrupt variation in thickness is relatively common in Cenozoic nonmarine deposits in California.
Trench A was dug across the apparent thinnest exposui' of the upper member, about 2 miles east of the GETR, to.plore for evidence of a fault that might be continuous with Herd's Verona fault to the northeast and account for the mapped variation in thickness. A fault was found in Trench A (later also exposed in nearby Trenches A-1, and A-2), but it could not be projected to the area of the GETR site. This fault is nearly vertical,,triking at about N70*U 1136 208 pg.%3
3
>r lateral displacement indicated (at a high angle to the searched 'os fault.
new'y
- vered fault t the site, but i
by horizontal slickensides.
It L s
may be an unmapped continuation of the Williams fault to the southeast (Hall,1953).
Amount of displacement along this fault is unknown, for undistinguished Livermore Gravels are present on both sides. Nor is the recency of displacement apparent, for landsliding and soil creep have modified evidence in Trench A-2, the best exposure we saw.
r Conclusion A newly discovered (for the site) vertical fault with horizontal displacement tras found in the A trenches, some 2 miles east of the GETR.
Its strike (about N70*W), dip, and sense of displacement are all incompatible with those required for continuity with fault 1 (the Verona fault of Herd,1977).
Trench E (See Figure 2 for location)
Bulldozer Trench E, morn than 1,000 feet long, was excavated across the mapped trace of Herd's postulated Verona fault almost 3 miles northwest of the GETR. No evidence was found for a fault that might be continuous with the Verona. Several minor faults were found that dip to the southwest. These are i
probably related to local folding deformation, and all are overlain by undisturbed pleistocene paleosols.
A syncline, exposed in the trench, trends northwest with a warp to nearly due west in the vicinity of the end of Sycamore Road. This warp is the probable reason'for near vertical beds at the end of Sycamore Road that have been interpreted as being suggestive of faulting.
1136 209~
Conclusion Unfaulted continuity of paleosols in Trench E signiffeantly restrict the prcbability that fault 1 (Herd's Verona fault) continues from the GETR area to connect with any fault to the northwest.
L_ p *2?
_14 Discussion The faults found in the T, B, and H series trenches are all very similar.
In all cases the angle is low, mostly ranging from 10 to 30 degrees, dipping to the northeast, with dip slip slickensides. Movement has occurred in multiple events, indicated by successively larger displaceme..cs of successively older units.
Although the characteristics of the modern soil would not permit preser-vation of fault displacement features within it for more than a few decades at most, lack of specific topographic expressions of faults 1, 2, and 3 (see Figure 3) strongly suggest that there has been no displacement in recent plogic time.
!!cwever, based on evidence of as much as a few feet of offset of the stoneline horizon, which is older than about 9,000 years, the youngest displacements on these faults probably was early Holocene time.
A well developed paleosol, with a probable minimum age of abcut 70,000 years, is offset as much as 11 feet, with some evidence of more than one event accounting for this total. This, plus the stoneline offset, indicates at least two, but probably more displacements of the paleosol.
The alluvium-colluvium on which the paleosol developed was deposited more than about 125,C00 years ago. Livermore Gravels have been thrust over these deposits more than S0 feet in Trench B-2.
Total maximum displacement of this unit was not observable in the trenches, but general censiderations suggest it may be 100 to a few hundred feet. Thus, the maximum displacement en all of the thrusts was more than abcut 125,000 years ago.
An important aspect of these cbservations is that displacements were repeated alonc the same shear :cnes in weakly consolidated materials over 1136 L10 a very lcng pericd of time.
The hilly area above the GETR site is a large, dissected, amphitheater-like feature (see Figure 6'.
This amphitheater appears to be of ancier.t
.~
A p*
g
,'s)Qpe y, s o
cETR g
',/,
Approxi ate h ad r
'l'
=
g EXPLANATION g
.C0 0U R ERV^L FE T Trench g
9
,9 ES g
jitd 4
(
Figure 4)
"lllCl3 h4 O
O 2000 4000
.lEl3 k
p
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FEET SCALE: I"s 2000'
\\. ""
r----
,,i u-TOPOGRAPHY OF THE GREATER m
l N N.
GETR VICINITY Showing postulated landslides
16 landslide origin when viewed on aerial photos, certain contour maps of the right scale and interval, and on the ground from certain points.
Considerable erosion has taken place since the tire the slide occurred, for the headscarp area appears to have migrated upslope, and there has been extensive dissection of the slide mass by ephemeral streams ficwing dcwnslope across the beds.
III ORIGIN OF THE FAULTS There is no conclusive evidence in the trench exposures that proves the origin of the thrust shears, for both tectonic thrust faulting and large scale landsliding could cause these, structures.
Mcwever, other aspects of the geologic and topographic setting are helpful in making a judgmental evaluation of their prcbable cause.
Scme or all of these aspects will be weighed differently by different geologists, thus the various judgments will also diff.er.
Arguments for and against tectonic faulting A principal argument in favor of a tectonic crigin of the thrust faults is the fact that the area is within an active tectenic regime. Three major, historically active faults pass scutheast of the GETR site:
the Calaveras at about 2 miles, the Hayward at abcut 8 miles, and the San Andreas at abcut 27 miles.
The Livermore and Greenville fault zones pass abcut 5 and 11 miles, respectively, northeast of the GETR. All five of these fault zenes strike north no-thwest, and the historically active caes have exhibited right lateral displacements.
jj}g
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The only way for an arcuate, west northwest trending, icw angle thrust fault like the propcsed Verona to fit into this tectenic framework is fer it to cce py a zone of ccepression between the Calaveras fault and the Livermore Valley region to the certh and northeast.
However, Liver cre Valley is a
~^'ycung,'Enwarped or dcwnfaulted area, suggesting tensional stresses during
1,7,_
recent geologic time. Thus, the Verona fault north south compression hypothesis does not appear to be compatib!a with the ongoing tectenic reg're.
Another argument not favorable to a tectonic origin of the thrust faults is the lack of evidence of continuity of such faulting along the.
trend of the proposed Verona away frca the area of postulated 'iddsliding.
If the Verona exists as a significant structural feature (e.g., sufficient to uplift the ridge front severai hundred feet as suggested by Herd,19'/7), then certain conditions or relatienships with other faults should also exist.
From the GETR area fault 1 should continue to the northwest to join the Calaveras fault zone or some other strike slip fault (such as the controversial Pleasanton fault) lying northeast of the Calaveras.
Bulldozer Trench E, more than 1000 feet long, explored for such a continuation across the mapped trace of the Verena fault (Herd,1977) about 3 miles northwest of the GETR, but did not expose any appropriate fault of shear. A much longer seismic traverse across Happy Valley in the vicinity of Trench E (ESA,1979, Appendix C) cid not definitely indicate a fault, but the quality of part of the record was nct adequate to disprove the presence of a fault at depth south of Trench E.
To the east and scutheast of the GETR site, continuity of the postulated Verona fault is ccnstrained by unfaulted continuity of outcrop of the relatively resistant middle conglecerate unit of the Livennere Gravels abcut 4CCO feet easterly of Trench T-1.
It might be postulated that the Verena joins the Las Positas fault (Herd,1977) to the northeast of Trench T-1, but at least two points argue against such centinuity.
First, the A series trenches cut across the ecst likely continuation in this direction, and did not expcse an appropriate fault.
(Such a fault should have a bearing at Trench A of about N 60 E, but as noted earlier, a fault fcund in the A trenches :: rends abcut N 70 W.) Second, the Las Fcsitas fault, as described by Herd (1977), is a steeply dipping cne w'th predominantly vertical displacement, scucheast side up.
This sense of dis-lace ent appears to be incccpatible with the 1 agle,}sjefthdirectedthrustin;
. ammer
~~ -
exhibited by the Verona shears ( see Figure 2).
Thus, the thrusting appears to be constrained in both directions away from the postulated landsliding on the southwestern flanks of the main ridge, and the length of the postulated Verona restricted to about 20,000 feet at most.
The dips of the thrust surfaces exposed in the trenches also b.ar on the judgment of probable mechanism. The icw dips at the base of the ridge (Trenches T-1, T-2, 3-1, and B-3), compared to the scmewhat steeper dips away from the ridge (Trenches B-2 and H) appear to be incompatible with a single thrust fault system (see Figures 4 and5 for graphic represt:ntations of these dips).
Arouments for and acainst landslidino The gross topographic expression of the southwest flank of the main ridge is one of the strongest arguments in favor of landsliding as the
~
mechanism that produced the thrust shears seen in the trenches. The large, arcuate, deeply dissected amphitheater on the ridge back of the GETR, along with the bulging, abrupt toe of the slepe, in, gross form is character-istic of rotational slump landslides (Figure 6). Such slope failares, both large and small, are relatively abundant in the Californ.a Coast Ranges.
In our judgment, it is highly unlikely that differntial erosion, an alter-native explanation for this distinctive topcgraphic form, would produce the gecmetry that is so characteristic of slope failures.
Also compatible with landsliding is the relatively weak character of the o;iper unit of the Livemore Gravels that underlies the ridge and the GE*R area. This unit consists of a crudely interbedded sequence of weakly con-solidated clayey, siity, sandy, and gravelly beds and lenses.
Cne of the strongest arguments against a landslide crigh for the thrust shears is that distinctive pullaway features or steeply dipping shears were t r.. i. >3 1136 214 W
~
found in only one of the three trenches (0, F, and G, see Figure 6 ) dug to search for such features near the head of the postulated landslide. Only Trench G, the middle one of the thre'e, exposed shears with proper orien-tation and location for the features sought. Deep dissection of the land-slide = ass and upslope migration and dissection of the headscarp since the principal slope failure more than 125,000 years ago make location of these original headscarp features much more diff' cult than location of the sole thrusts at the tce of the landslide mass.
The thrust faults in Trenches B-2 and H have been censidered inccmpatible with lands'lide origin because they are located far from the base of the ridge. The average slepe frca base of the ridge to faults 2 and 3 is about 3.5 degree. A graphic representatien of this sicpe, to scale, between faults 1 and 2 is shewn in Fiqure 4.
There are many precedents for land-sliding on slopes as icw as this, most of them probably induced by earth-quakes. One example is the Juvenile Hall landslide triggered by the San Fernando earthquake of 1971. This landslide was about 4000 feet long, with displacements of a few feet on an average slepe of abcut 0.6 degrees (1 percent), and trenching revealed evidence of additional dis-placements prior to the 1971 event (Smith and Fallgren,1975, p.158).
Evaluatien of evidence In sum, it is apparent that the evidence available does not concusively prove er disprove the origin of the fualts exposed in the trenches.
It is our judgment, bewever, that the weight of evidence is strengly in favor of a landslide origin for these features.
SIGNIFICANCE OF FA' LT VS. LANDSLIOE ORIGIN OF THE FAL'LTS IN TERMS OF IV J
GECLCGIC HAZARD TO TFE SITE l }
If the faults are tectonic in origin, future displacements en them will eccur caly after sufficient stress has accumulated iccally to require
P00RORIGNAL
~J 1-
-2o-relief by earthquake or creep cechani;ms.
Such events should be less frequent than the total of those on nearby major faults of this tectonic regime, such as the Calaveras fault.
On the other hand, if the faults are the result of landsliding, further activity might be triggered by various influences or events, especially climatic and seismic ones. Our calculations indicate that without w rong seismic stimulation, the postulated landslike masses are stable under the dry climatic conditions that now prevail in the area.
However, calculations discussed below also indicate that the upper landslide mass, above fault 1, might be activated by an offsite earthquake generating 0.3 acceleration at the site, and that the landslide mass or masses above faults 2 and 3 could be activated by accei? ration at the site of about 0.6g or greater.
Stability analyses were qerformed using cross-sectional views chosen to represent movement on fault 1 and on fault 2 shear.
The first was drawn by ESA along the crest of the north northwest trending spur ridge north of the GETR (ESA,1978 C, Figure 1).
Our analysis was made on the sectica shown in the ESA report as Figure 2.
The strength paramenters used were:
cohesion of 300 and 1000 psf, angle of internal friction of 16.5, and unit weight of 133 pcf. The analysis was made using the simplified methed of slices (l.ambe and Whitman, 1969, p. 35g).
These analyses resulted in factors of safety of 2.02 for a coheswn of 300 psf and 2.31 for a cohesion of 1000 psf.
The analysis was then repeated using acceleration values of 0.2, 0.25, and 0.5 g, with cohesion value as before.
The acceleration value of 0.2 g gave factors of safety of 1.20 and 1.37 for the two cchesion values.
The acceleration value of 0.25 g gave safety factors of 1.09 and 1.25 and that of 0.5 g gave safety factor of 0.53 and o 55-r136 216 Another analysis was made using a cross-section shown on Figure 8 of Yl
~
21 ESA, 1979. This was an assumed slide along the fault found in Trench B-2.
~
Strength para = enters used were a cohesion of 300 psf and others as before.
With no acceleration, the factor of safety was 3.39. Acceleration values of 0.3 and 0.5 g were then used, and the factor. of safety was 1.51 with 0.2 g, and 1.13 with 0.5 g.
Again the method used was the simplified method of slices.
(A safety factor of 1 implies the mass is theoretically exactly in balance; I
greater than 1 implies greater and greater stability, less than 1 implies instability under the assumed conditions.)
Because nearby major earthquakes that could generate such accelerations in the vicinity of the GETR are likely to be more frequent than offset events on a Verona fault, displacement by slope failure mechanisms are more likely than surface fault displacements at the site.
For example, during the last 150 years there have been at least 7 severe earthquakes on the Calaveras, Hayward, and San Andreas faults that wculd have generated significant ground ection at the GETR site. These were in 1836, 1853, 1861, 1868, 1897, 1903, and 1906 (Blume,1973, p.11,12), and probably all were accompanied by surface displacement. The frequency implication of the landslide interpretation should be considered in establishing design criteria for the facility.
Y INTERPRETATION OF THE EVIDENCE FOR DESIGN CRITERIA The trenches at Vallecitos revealed important aspects of the distribution and history of displacements of the thrust faults.
In cur judgment, these empirical data should be the principal basis for evaluating the significance of the thrusts as they relate to geologic ha ards to the GETR structure.
Three principal aspects of the empirical data, sumari:ed as follows, are independent of the mechanism of origin of the thrusts and le th A..;e gt;
.~
s.
inferences and conclusions indicated:
(1) The two thrust faults that bracket the GETF., faults 1 and 2 (see Figure 3), have similar histories of multiple displacements during the last 125,000 years or more. This fact is evident frem successively larger displacements of alder units along each fault (Shlemon, 19790, and Earth Sciences Associates, 1979). Fica this evidence we conclude that any future activity resulting from forces that produced faults 1 and 2 will very 1,ikely take place along the same shear surfaces as in the past.
(2) Excellent exposures in Trenches 8-1, B-2, and B-3 indicate that the multiple displacements that have occurred during the Icst 70,000 years probably have occurred in increments of about 3 feet or less per event on each of these two thrusts (Shiemon, 19798).
This evidence strongly suggests that offsets that might result from future activity along these faults will very likely be of the order of a few feet at most.
(3) Trench B-1, scme 1080 feet long and with a northeast trend (approximately perpendicular to the thrust shears), passes about 300 feet northwest of the GETR. This trench exposed unfaultad late Quaternary alluvial fan and colluvial deposits that have poorly developed paleosol horizons (see Figure 7). We agree with Shlemon (1979C, p. B-3) that the oldest of these unfaulted sediments
... exposed in Trench B-1, directly opposite the GETR, pertain to (oxygen isotope) stage 6, and thus most likely were laid dcwn between about 123,000 and 195,0C0 years ago."
Thus it is unlikely that any tectonic or landslide-generated faults wi:h displacement activity younger than abcut 123,000 years cut the f:undatien site of gO the GETR structure. 'qsUs.- ;;,.. iE,I
. =.-. -.1 -,.n. )*. e. T 'rj ! T a 3 !i ~ 1 i p fault 1 n; 4 ** Stsoag releosol (Step 61 fault 2 " " " ~ ' ' ' .si ua.scon.iumasi.e.21, 4 .j.74,'... *.n. F M8"n son .mu m. g,,,_ _ r a,,- ~ ~ a.e ~,~ 4 r !) :i t. ' Q nu wo m isie p 4: lr....,,.... m ' ' '.,......p " : o. l ' 1.' R, 'y3:-L:' es,,, sa.w gs,e, s /, g,,p 3 /- r o '* -2 A mu ,n Base of Tsemh I f l he i CD Figure 7: Schematic diagram showing relationship of late Quaternary soils and sediments exposed in Trench B-1 near the GETR site. Ilot to scale; stages refer to marine isotope chronology. For detailed log see ESA,1979. Figure E-4, (f.dapted from Shlemon, 1979C, Figure 1) n 5 u = c os m M
==~ tt) rv N b 'O'
24 In our judgment, this last inference, combined with the evidence of multiple displacer.ents on faults 1 and 2 during at least the last 125,000 years, suggests a very low probability of a new fault develeping in the GETR foundation during the useful life of the' structure, regardless of the mechanism of origin of the faults. Mcwever, if surface offset should occur at the GETR in the future, evidence centiened in (2), above, implies that it should amount to a few feet at most, conservatively estimated to be 3 feet. In general, it is our judgment that a future displacement event in the site area, whether of tectonic or landslide origin, might result in slip on fault 2, exposed in Trench B-2. This would lead to movement of the site on which the GETR is located by as much as a few feet toward the southwest. Because fault 2 is curved, the surface of the moving bicek (including the GETR site) might be differentially deformed and the GETR might be rotated out of plumb by a small amount. Ground motion to be excected at the GETR site Earth Sciences Associates (ESA, 19780) presented arguments to down-grade the expected peak accelerations at the GETR site relative to the recorded 1971 San Fernando earthquake ground motions. These arguments are based on: (1) higher levels of attenuation in Franciscan rocks as cpposed to granite (the basement rocks at seis=ogenic depths beneath the GETR area and the Sei Fernando area, respectively); and (2) lower rock strength and confining pressures at the GETR site characteri:ed by Icw stress drop "interplate" earthquakes. The question arises, hcwever, whether current theory is able to permit quantification of these differences, at least with the confidence necessary to justify lcwering design specificatic s a nuclear reactor. Eayr Sciences Associates suggested that the maximu i "crcund" motion .pe 4 I
25 at the site will most likely be in the range of 0.3 g to 0.5 g, based on theoretical considerations of source and transmission path geology (ESA,19780). If we assume that the Calaveras fault generates ti7 or ti7.5 earthquake at a fault distance of about 2 miles, the corresponding bed rock ' acceleration using the attenuation curves of Schnabel and Seed (1973), approximately 0.8 g ap;: ears to be an appropriate and conservative value for design. It seems that ground motien predicted by Earth Sciences Associates ~ (EAS, 19780) is too low. It may be more appropriate to use observational data rather than theoretical estimates at this time. The mapped length of Herd's Verona fault (Herd,1977) is less than about 10 km (about 6 miles);as discussed in Section III of this report. Available evidence indicates that such a fault does not likely continue to the northwest or east. A 10'km length corresponds to about MS, using Slemons (1977) surface rupture - earthquake magnitude relationship. Since the postulated Verona fault is less than 400 feet from the GETR, the bedrock acceleration would not be less than about 0.589, using the attenuation curves of Schnabel and Seed (1973). Since these curves do not take near-field ground motion effects into account, an appropriate value of peak ground acceleration for an on-site event could be somewhat higher. 1136 221 M
- ~
q a usa ust u s#1 LISTING OF SUBMITTALS MADE TO THE NRC Date Subject Submitted I. Submittal in Response to Request for Additional Infomation Re: License Renewal - consisting of the follcwing reports 6/10/77 Load and Lifetime Study, G.E. NEDO 12624' Criteria and Bases Summary for Structures, Piping Systems and Components ECAC 117.08 Primary, Secondary & Pool Cooling Systems, Vol.1. EDAC 117.04 Pool and Canal Emergency Recirculation Systems, EDAC 117.05 Containment Shell & Related Structures and Containment Shell Penetrations EDAC 117.06 Equipment Building, EDAC 117.02 Miscellaneous Systems & Ccmponents ECAC 117.09 Investigation of Alternates for Modifying the GETR Building for Postulated Earthquake Shear Forces EDAC 117.13 Analysis of Postulated Shipping Cask Drop Accidents within the Reactor Building at the GETR Facility, EDAC 117.12 Seismic & Geologic Investigations for the GETR Facility, Blume Seismic Analysis of the Reactor Building for the GETR Facility Blume Investigation of Reactor Building for Potential Concrete Cracking Under Seismic Loading, Blume Thermal, Pressure Dead-Load and Seismic Analysis of the Primary Cooling System at the GETR Facility, Vol.1. Blume II. Submittal in Response to Request for Additional Information Re: License Renewal - consisting of the following reports 8/24/77 GETR Safety Analysis Report, NEDO 12622 GETR Environmental Information Report, NECO 12623 Coastdown Hydraulic Characteristics for GETR, NECO 12625 Ther al-Hydr 3ulic Perfomance of GETR Emergency Cooling System NECO 12626 A Coupled Neutron Kinetics-Thermal Hydraulics Model for the GETR Using the REtAP-4 Computer Program, NECO 12627 System Ilydraulic Analytical (SHAG) Mcdel Used for Analy:ing loss of Flow Events in the GETR, NECO 12623 GLTR Containment Leak Test Study, NECO 12629 r,rTR."oltichannel Core Model for Simulating Internal l l } 6 '?} } Natural Circulation, NIDO IPf,63 Proposed New GETR Technical Specifications General Electric Financial Statement n.m
Oate Subject Suhaitted i III. Response to the NRC Order to Show Cause. 10/14/77 11/11/77 (consisting of the following) Attachment No. 1 - Summary of Geological Investigations 1. November 9,1977 Memorandum " Discussion of Evidence for the Existence of the Postulated Verona Fault Near the GETR Vallecitos Site". 2. Addendum I to 11/9/77 Memorandum " Evidence of the Postulated Verona Fault Near the GETR Vallecitos Site". Attachment No. 2 - Sumary of Seismolooical and Structural As solstnen t Attachment No. 3 - Surnnary of Thermal Hydraulic Ef fects and End Conditions Attachment No. 4 - Suminary of Modifications Recuired Before Startuo Attachment No. 5 - Sumary of Radiological Assessment IV. Addendum II to Memorandum of 11/9/77 11/18/77 V. Addendum !!! to Memorandum of 11/9/77 12/5/77 VI. Submittal oonsisting of 1 Attachment 12/16/77 Attachment - Letter from Lindvall, Richter & Associates ,da ted 12/9/ 77, and Study from ECAC, Seism 1c Criteria and Basis for Structural Analysis of Reactor Building TAttac cent 1) VII. Submittal consisting of 4 Attachments 1/5/78 - Photograohs of the GETR Foundation Escavation - Preliminary _L,onqing{Tinal data wi11 be included Data for Trench il and Bor_i,njs_f,1., 82, v 3 ~~ with the final 2co l_oli c_r,c c o rt to be suteni tted in accrodimatele two weeksl - List of encineering and <:eologic reports on file in the of fice of the Ala"'oda County Geologist whicn have been reviewed to determine their blev,Incy to the nn,-]O,inj ]enlogi [investl[ation \\ \\\\ t _~... c. 4 sr
~ ( j , - Memorandum Recort Issued by the California Division of Mines and Geolocy, cated December 22, 1977 VIII. Submittal consisting of 1 Attachment I/6/78 " Attachment No.1 - Seismic Criteria for GETR Reactor Building - ED D roject No. 117-214, 1/6/76 IX. Submittal consisting of 1 Attachment 1/20/78 Attachment No.1 - Clarifying and/or Amo11fvinq Information Contained in the Novemoer 11, 1977 Subiit t ta l X. Submittal consisting of 1 Attachment 1/30/78 Attach ent No.1 - GETR Fuel Temperature for Fuel Stored in the Canal in Air. D. C. Brown,1/21/ 78 XI. Submittal consisting of 1 Attachnent 2/3/78 ' Attachment No.1 - Seismic Analysis of Reactor Building General Electric Test Raactor, Phase I 'EONC,2/:/f8 XII. Submittal consisting of 1 Attachment 2/14/78 Attachment No.1 - Table, GETR Seismic Scrams 1958-1978 XIII. Submittal consisting of 1 Attachment 2/24/78 Attachment No.1 - Uqda_te of Analytical and Modification In for na tion, 2/24/ 78 XIV. Submittal consisting of 1 Attachment - Geologic Investigation 3/3/78 of the General Electric Test Reactor Site, ESA, Feb.1978 XV. Submittal consisting of 3 Attachments 3/31/78 Attac~ ant No. 1 - Cetermination of Vibratory Loads to be Centined wi th Fault 01splacement Loads (CAC 117-217.01) Attachment No. 2 - Excerats from References to Show Context of Quotes Used in E:AC 117-217.01) Attachment No. 3 - Three reports under nne cnver (a) Effects of Earthquake Source and Trans-mission Path Geology on Strong Ground Motion at GETR Site 11() 224 (b) Ground Motion and Displacement on Hypothetic Verena Fault (c) Geologic and Sei'rologic Para ~eters -..a 2 'y#,M '- V' of '...r.Iir 14 ',* r: er; V,. t irsn ' s.c rird, d
~ -4 ~ ~ Date Subject Submitted XVI. Subittal consisting of i attachnent 4/7/78 Attachment No.1 - Addendum I to ESA Geologic Investigation XVII. Submittal consisting of 2 attachments 5/1/78 Attachment No.1 - Slides Presented to NRC on 4/17/78 Attachment No. 2 - (Part 1) Original Reactor Nilding Concrete Strength Data (taken at time of construction - 1957/1958) (Part 2) Reactor Building Concrete Strenoth Cata (taken in January 1978) XVIII. Submittal consisting of 13 attachments 5/22/78 Copies of Geological Documents referenced in ESA Geologic Investigation Re:: ort XIX. Submittal consisting of 1 attachment 6/2/78 Attachment No.1 - ECAC Phase II Report XX. Sutmittal consisting of 9 Attachnents ~7/5/78 Attachments - Miscellaneous Geology Reports of Pleasanton Area XXI. Sutrnittal consisting of 1 attachment 7/14/78 Attachment - ESA Landslide Stability Report XXII. Submittal consisting of 10 Attachments 7/20/78 Attachments - 10 Update Reports to NRC Order to Show Cause XXIII. Submittal consisting of - Response to NRC Request for Additional Information on the Phase II Report 7/26/78 XXIV. Sutnittal consisting-of - Revised pages for Previously Submitted ECAC Reports 8/3/78 XXV. Submittal censisting of - Proposed Program for Additional Geo-logical Work 8/18/78 XXVI. Suttnittal consisting of - Changed Program for Additional Geo-logical Work 8/27/78 XXVII. Submittal censisting of - Response to NRC's 18 Questions 10/6/78 MVIII. Submittal consi: ting of - Six Sets of Geological Trench Logs 11/2/78 XXIX. Submittal consisting of - Logs of Trenches at or Near VNC 11/29/78 XXX. Sutmittal censisting of - Letter Anpiifying and Clarifying 1/22/79 Cescription of Two Tedundant 36 225 Control linits we:
7_ ~ 8/13/79 Submittals Made to NRC Since February 28, 1979 Date Subject Submitted XXXI. Submittal consisting of 3 Attachments: 2/28/79 - - List of Submittals Made to the NRC - Geological Ir.vestigation-Phase II. General Electric Test Reactor Site, Vallecitee, California - Evaluation of Seismic Hazard at the General Electric Test Reactor Site, Alameda County. California by Richard H. Jahns XXXII. Submittal consisting of - Errata sheets for the Geological Invest-3/13/79 igation-Phase II rcport XXXIII. Submittal consisting of 1 Attachment 3/27/79 Attachment - Respor.ses to all comments which were made by the NRC or their consultants in the meetin.g of 3/20/79 with General Electric Company XXXIV. Submittal consisting of 1 Attachment 4/13/79 Attachment - Probability Analysis of Surface Rupture Offset Beneath Reactor Building - General 'lectric Test Reactor Report - ECAC-117-217.13 XXXV. Submittal consisting of 1 Attachment 6/25/79 Attachment - Responses to questions raised regarding the Geological Investigation-Phase II~ General Electric Test Reactor Site Report XXXVI. Submittal consisting of 1 Attachment 7/9/79 Attachment - Responses to questions in Letter dated 6/27/79 R. W. Reid (NRC) to R. W. Darmitzel (GE) regard-ing structural modifications XXXVII. Submittal consisting of Letter to Chris Nelson (NRC) from 7/12/79 R. W. Darmitzel (GE) regarding USGS Professional Paper #943 b 226 M
f MEETING SLH"ARY DISTRIBUTION ORBd4 i Mr. R. W. Darmitzel, Manager Irradiation Processing Product Section Vallecitos Nuclear Center General Electric Company P. O. Box 460 Pleasanton, California 94566 cc: See next page Dec' et File R. Reid @LPDR V. Noon.an P. Check ORB #4 Rdg G. Lainas NRR Rdg G. Knignton H. Centon Project Manager -CNelson E. G. Case OELD OI&E (3) D. Eisenhut R. Ingram R. Vollmer R. Fraley, ACRS (16) W. Russell Program Support Branch
- 3. Grimes TERA T. J. Carter J. R. Buchanan A. Schwencer Meeting Summary File D. Ziemann NRC Participants T. I;polito LGossick W. Gammill ECase
.L. Shao STreby J. Miller DSwanson 'nBurkha rd t 1136 227 .M
~o General Electric Company rt'r 3 I Uvil U 113l$ 1 cc w/ enclosure (s): California Department of Health ATTN: Chief Environmental Radiation Dr. Harry Foreman, Member Control Unit Atomic Safety and Licensing Scard Radiologic Health Section ' University of Minnesota Box 395, Mayo 714 P Street, Rocm 498 Sacramento, California 95184 Minneapolis, Minnesota 55455 Honorable Ronald V. Dellums Ms. Sarb' ara Shockley ATTN: Ms. Nancy Snow 1890 5cckman Road General Celivery, Civic Center San Lorenzo, California 94580 Station Oakland, Califernia 94604 Advisc y Committee en Reacter Saf+ guards Friends of the Earth U. S. Nuclear Regulatcry Ccmmission ATTN: W. Andrew Baldwin, Esquire Washington, D. C. 20555 Legal Director 12 Spear Street San Francisco, California 9:105 Jed Semit, Esquire 100 Bush Street Suite 304 Scn Francisco, California 94104 Herbert Grossman, Esq., Chairman Atcmic Safety and Licensing Board U. S. Nuclear Regulatcry Ccamission Washington, D. C. 20555 Mr. Gustave A. Linenberger, Member Atomic Safety and Licensing Board U. S. Nuclear Regulatory Ccamission Washington, D. C. 20535 George Edgar, Esquire Morgan, Lewis & Beckius 1800 M Street, NH Washin; ten, D. C. 20036 1136 228 .-.}}