ML20031A113
| ML20031A113 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 09/11/1981 |
| From: | Mendez J, Pigott D ELGORR, ORRICK, HERRINGTON & SUTCLIFFE, SAN DIEGO GAS & ELECTRIC CO., SOUTHERN CALIFORNIA EDISON CO. |
| To: | Atomic Safety and Licensing Board Panel |
| References | |
| ISSUANCES-OL, NUDOCS 8109210008 | |
| Download: ML20031A113 (47) | |
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In the Matter of
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Docket Nos. 50-361 OL
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50-362 OL SOUTHERN CALIFORNIA
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(San Onofre Nuclear Generating
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Station, Units 2 and 3)
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APPLICANTS' BRIEF IN SUPPORT OF PROPOSED FINDINGS OF FACT AND CONCLUSIONS OF LAW ON GEOLOGY / SEISMOLOGY ISSUES eis $Y?/
df"l- 'h DAVID R. PIGOTT 9
EDWARD B.
ROGIN
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93 m7 JOHN A. MENDEZ
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ammmpu Of CRRICK, HERRINGTON & SUTCLIFFE "fx A Professional Corporation h [yGS f
600 Montgomery Street cot San Francisco, California 94111 Telephone:
(415) 392-1122 CHARLES R.
KOCHER JAMES A. BEOLETTO SOUTHERN CALIFORNIA EDISON COMPANY P.O.
Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Telephone:
(213) 572-1900 Attorneys for Applicants Southern California Edison Company and San Diego Gas & Electric Company Dated:
September 11, 1981.
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8109210008 810911 DR ADOCK 050003gg 6
r DAVID R. PIGOTT EDWARD B. ROGIN SAMUEL B. CASEY JOHN A. MENDEZ Of ORRICK, HERRINGTON & SUTCLIFFE A Professional Corporation 600 Montgomery Street San Francisco, California 94111 Telephone:
(415) 392-1122 CHARLES R. KOCHER JAMES A. BEOLETTO SOUTHERN CALIFORNIA EDISON COMPANY P.O Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Telephone:
(213) 572-1900.
Attorneys for Applicants Eouthern California Edison Company and San Diego Gas & Electric Company -
UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
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Docket Nos. 50-361 OL
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50-362 OL SOUTHERN CALIFORNIA
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APPLICANTS' BRIEF IN
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SUPPORT OF PROPOSED (San Onofre Nuclear Generating
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FINDINGS OF FACT AND Station, Units 2 and 3)
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CONCLUSIONS OF LAW ON
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GEOLOGY /SEISMCLOGY
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ISSUES Applicants, SOUTHERN CALIFORNIA EDISON CO.tPANY and SAN DIEGO GAS & ELECTRIC COMPANY (" Applicants) roubmit this brief on the geology and seismology issues in the above mat:ter pursuant to Stipulation and Confirming Order of the Atomic Safety and Licensing Board (" Board") (Tr. 8449) and 10 C.F.R. 5 2.754.
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j INTRODUCTION The geology / seismology portion of the public hearings on Applicants' application for a full term operating license for San Onofre Nuclear Generating Station Units 2 and 3 (SONGS) were held before the Atomic Safety and Licensing Board in San Diego, California from June 22-July 2, 1981; July 8-July 17, 1981; and July 27-August 4, 1981.
The hearing consisted of twenty-five (25) days of testimony, cross-exav.instion, and rebuttal as well as four limited appearance sessions which were held on June 27, July 1, July 11, and July 29, 1981.
The following four isues were admitted by Board Order of May 29, 1981 and formed the basis of the geology / seismology portion of the licensing hearing.
Evidence was received by the Board on these four issues only:
- 1 Whether as a result of ground motion analysis techniques developed subsequent to issuance of the construction permit or data gathered from earthquakes which occurred subsequent to issuance of the construction permit, the seismic design btais for SONGS 2 & 3 is inadequate to protect the public health and safety.
- 2 Whether characterization of certain offshore geologic features as a zone of deformation, referred to as the Cristianitos Zone of Deformation (CZD), or whether any additisnal information about the CZD which became availaole subsequent to issuance of the construction permit, render the seismic design basis for SONGS 2 & 3 inadequate to protect the public health and safety.
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- 3 Whether the seismic design basis for SONGS 2 & 3 is inadequate to protect the public health and safety as a result of discoveries subsequent to issuance of the construction permit of the following geologic features:
(1)
ABCD features at the site; (2)
Features located at Trail 6, Target Canyon, Dead Dog Canyon, Horno Canyon, and " onshore faults E and F";
(3)
Such other features as the parties may agree are relevant to the seismology of the SONGS site or with respect to which Intervenor, Friends of the Earth, makes a threshold showing of relevance.
- 4 Whether based on the geologic and seismic characteristics of the OZD, including its length, assignment of M 7 as the maximum magnitude 3
earthquake for the OZD renders the seismic design basis for SONGS 2 & 3 inadequate to protect the public health and safety.
Pursuant to 10 C.F.R. 5 2.743(b) and Board Order, Applicants and the NRC Staff filed written testimony on the four issues on June 8, 1981.
Intervenors, Friends of the Earth, et al.
(" FOE") filed written testimony on June 12, i
1981.
IntervenorS, Groups United Against Radiation Dangers
(" GUARD") elected not to participate in the geology /
seismology portion of the licensing hearings.
4 Eleven (11) witnesses presented seventeen (l*,)
different pieces of testimony for Applicants in their direct case.
In addition five (5) witnesses (three (3) who had previously appeared in the hearings and two (2) who had not) presented rebuttsi testimony for the Applicants.
Seven (7) witnesses presented testimony on behalf of the NRC Staff and eight (8) witnesses testified in FOE's direct case.
Five (5) of FOE's witnesses appeared under subpoena -- Drs. John 3
1 t
Anderson, Clarence Allen, David Boore, Gordon Gastil, and Michael P. Kennedy, who also testified on behalf of the Staff in its direct case.
Mr. Richard Simon appeared as a witness and filed written testimony for FOE; however, Applicants' and Staff's motion to strike his testimony in its entirety was granted by the Board at the hearing.
Finally, Dr. J. Enrique Luco appeared as a Board witness and presented evidence on Issue #1 regarding ground motion analysis techniques, i.e.,
computer modeling studies.
A complete list of witnesses can be found commencing at Page 6 of Applicants' Proposed Findings of Fact and Conclusions of Law ("FF" No. 14).
Applicants identified fifty (50) exhibits during the course of the hearings, forty-eight (48) of which were admitted into evidence.
FOE identified twenty-eight (28) exhibits, eighteen (18) of which were admitted into evidence, the NRC Staff identified nine (9) exhibits, five (5) of which were admitted into evidence and the Board identified one exhibit.
A complete list of exhibits is also contained in Applicants' Preposed Findings of Fact and Conclusions of Law (FF No. 15).
Applicants presented their direct evidence on the four issues in reverse numerical order, i.e.,
4, 3,
2, and 1.
This Brief will be limited to those matters testified to and contained within those four issues, and will be presented in the same order.
4
~
1 1
II.
DISCUSSION A.
Issue #4:
Whether based on the geologic and seismic characteristics of the OZD, including its length, assignment of M 7 as the maximum s
magnitude earthquake for the OZD renders the seismic design basis for SONGS 2 and 3 inadequate to protect the public health and safety.
(1)
Geology The scope of the geologic investigations of the area relevant to SONGS is both extensive and intensive.
Geologic studies have been conducted from the northern extent of the hypothesized ?!fshore Zone of Deformation ("OZD") to Baj a California.
The studies have addressed the regional geology including the geomorphic province where SONGS is situated, the surrounding provinces, and the tectonic setting of southern California and Baja California (FF Nos. 52-71).
The studies have been both onshore (FF Nos. 24-27) and offshore (FF Hos. 28-46).
The OZD which is tne controlling feature for the site, has been investigated throughout its length as well as postulated extensions into Baja California (FF Nos. 24-47; 80).
As a result of a postulated extension of the OZD offshore Baja California, Applicants subpoenaed certain 5
offshore seismic reflection profiling and navigational data not previously available to Applicants.
Such profiles and navigational data were examined by Dr. David G. Moore and reduced to a structure map of the area studied (FF Nos.
90-95).
Applicants submit that the investigations required by 10 C.F.R. Part 100, App. A, IV have been performed.
In order to place the existing geology of the SONGS site and its surrounding geologic f,atures into context, Applicants presented evidence describing the evolution of the i
entire area.
Dr. Ehlig presented uncontroverted evidence =-
to the geologic evolution of the SONGS region.
Dr. Ehlig's testimony demonstrated that as a result of the overall sequence by which the region was formed, there is no structural relationship between the Cristianitos fault and the OZD (FF Nos. 105-122).
His discussion should also be considered in relation to issue #2 when determining whether, from an evolutionary standpoint, the postulated CZD should be expected to be some linking structure between the l
Cristianitos fault and the OZD.
FOE appears to support such a theory.
It is submitted that neither the present day geology nor the evolutionary history of the region supports such a hypothesis.
In a similar attempt to connect the Cristianitos, the CZD and the OZD, FOE made reference to the concept of
" wrench fault tectonics" as a theory that could breathe life l
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into the above hypothesis.
The invalicity of such an approach is reflected in the testimony of Dr. Ehlig.
One of the weaknesses of the concept is that it does cot allow for changes in the orientation of local stress fields through time.
Additionally, the earth's crust is inhomogeneous and now ruptures tend to follou surfaces of weakness.
The concept is of little value in the context of regional tectonic histories.
Applicants submit that there is no basis in wrench tectonic concepts for relating the Cristianitos fault and the OZD (FF Nos. 139-149).
(2)
Determination of Maximum Magnitude Event Applicants provided three witnesses who assessed the maximum magnitude for the OZD to be M 7.
The Applicants' s
witnesses, Dr. Stewart Smith, Dr. Perry Ehlig and Mr. Edward Heath each approached the problem from separate viewpoints.
Dr. Ehlig based his assessment on an evaluation of the geologic record, particularly the Quaternary record, the nature of the OZD, its features, geologic strain rate, slip-rate and tectonic setting.
Dr. Ehlig stated that a more probable maximum magnitude would be 6.5, but stated that M 7 s
is the largest that might occur along the OZD (FF No. 226).
Dr. S'ccwart Smith assessed the maximum magnitude to be M 7 based on four interrelated lines of evidence:
(1) the s
instrumental record for the last half-century, (2) the historic record of several centuries, (3) the geomorphic record of several hundred thousand years and the geologic 7
record of several centuries and (4) the geologic record of several million years (FF Nos. 225; 123-138).
4 Mr. Edward Heath relied primarily on the slip-rate / magnitude method to arrive at a maximum magnitudo of M 7 f r the OZD.
This method is new for use in assessing s
maximum magnitude for a geologic structure but is an outgrowth of the degrca-of-fault-activity approach which has been proposed and researched since about 1966.
The slip-rate / magnitude approach allows a more quantitative measure of earthquake potential (FF No. 152).
Mr. Heath's approach to the problem required a detailed geologic and seismologic assessment of the OZD.
This involved an assessment of each of the tectonic elements of the OZD; the Newport-Inglewood Zone of Deformation (NIZD),
the South Coast Offshore Zone of Deformation (SCOZD), the Rose Canyon Fault Zone (RCFZ) and an eliminaticr. of the Baja California faults as having an influence en the maximum magnitude of the OZD (FF Nos. 161-174).
Mr. Heath also assessed the regional seismicity and the seismicity of the OZD (FF Nos. 158-160; 178-180).
Having thoroughly assessed all geologic and seismic aspects of the region and the OZD, Mr. Heath selected the NIZD ac a representative model of the earthquake potential of the OZD (FF Nos. 175-177).
Mr. Heath evaluated empirical methods that have been used for estimating maximum magnitude.
These included 8
such methods as surface rupture length and displacement-per-event versus magnitude.
Singular application of such procedures allows no cross-check or verification of results.
The prime weakness in these approaches is that the style of faulting and the tectonic setting directly effect the relationship between magnitude and length of surface rupture, or amount of surface displacement, and are not considered reliable in the present circumstances (FF No. 181).
Mr. Heath discussed in detail the surface rupture-length / magnitude method.
This. concept is set forth by Dr. Slemmons in " State of the Art'for Assessing Earthquake Hazards in the United States," (1977).
Mr. Heath applied the curves developed in that document in a very conservative manner to the segments of the NIZD.
The conservatisms included use of ubsurface segment lengths as opposed to surface rupture lengths in the Slemmons curves, the use of a rupture length in excess of the mean value experienced by l
faults in the range of length of the OZD, and the application of curve E of Dr. Slemmons article which included strike-slip faults from all over the world, some which are similar and j
some which are significantly different from the OZD (FF Nos.
182-185).
Again using Slemmons' work, Heath estimated that a j
hypothetical earthquake of magnitude 7.5 on the OZD could l
l produce up to 3.2 meters of surface displacement in a single event.
Surface displacements of this amount on the OZD are l
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i i
4 not supported by the geologic evidence and are certainly not characteristic even of the more active NIZD.
As was concluded by other experts, the geomorphic expression of the OZD simply does not indicate the occurrence of events in excess of magnitude 7 in geologic history.
In applying the slip-rate / magnitude method, Mr.
Heath carefully examined all available slip-rate data relevant to the OZD.
In order to establish geologic slip-rate it is necessary to have good stratigraphic control that is age datable and also a measurement of horicontal or lateral separation of the control units across a fault (FF No. 195).
For this reason a number of faults were not considered in the slip-rate analysis.
The San Miguel and Vallecitos faults in Baja California do not have sufficient data with respect to the period of time over which movement has occurred on those faults to develoo a meaningful slip-rate.
Additionally, the Rose Canyon fault does not have data of sufficient reliability to be included in Mr. Heath's analysis (FF Nos. 196-207).
Certain faults were also excluded because of styles of faulting and tectonic environments different than found on the OZD.
Slip-rate magnitude data for the Japanese faults were not used because they are in a tectenic environment much different than found at San Onofre (FF Nos. 208-211).
Once having developed the data base, the geologic slip-rate for the various faults was plotted against the 10 i
i
magnitudes of the corresponding largest historical earthquakes on those faults.
The line bounding the empirical observations indicated a consistent limit to the size of an earthquake associated with the geologic slip-rate of the strike-slip faults examined.
That line was then enveloped and for conservatism was arbitrarily increased a magnitude range of.2 of a unit for each earthquake used.
Since the slip-rate data is not absolutely precise, a range of data was used for conservatism.
The maximum ranges of slip-rates was combined with the magnitude range to establish a maximum earthquake limit line (MEL) that was ' lotted against p
magnitude (FF Nos. 212-218).
Using the slip-rate magnitude method and applying it in the most conservative manner, the maximum magnitude for the NIZD is M 7.0 (FF Nos. 219-221).
s The NRC Staff and its consultant, Dr. D. Burton Slemmons, confirmed M ? as the appropriate maximum magnitude s
to be assigned to the OZD.
Their conclusion rested upcn a number of approaches including a review of the slip-rate magnitude procedure (UF Nos. 223-227).
(3)
Empirical Evaluation of Strong Ground Motion Once having determined that M 7 in the appropriate s
magnitude event to be assigned the OZD, extensive study of available relevant earthquake acceleration data was studied to determine whether.67g is the appropriate anchor point for the design response spectrum.
Two separate studies were 11
conducted on behalf of Applicants to determine the appropriate Peak Ground Acceleration ("PGA") and the appropriate response spectrum.
Mr. Wight performed a regression analysis using 192 peak ground acceleration recordings from 22 different earthquakes.
That data set was limited to recordings within 50 km of the causative fault, stations where the motion was statistically consistent with the geology at SONGS, and where instruments were located either in the free field or at ground level or in the basement of small buildings.
The mean prediction of his analysis was.33g with an 84th percentile prediction of
.52g.
Based on this study, the design peak ground acceleration of.67g at SONGS ia conservative (FF Nos.
228-232).
Dr. Idriss performed a separate independent analysis to determine both the appropriate PGA and response spectrum to be associated with the SONGS 2 & 3 DBE.
The result of his analysis was.63g as the 84th percentile l
l instrumental PGA for a magnitude 7 earthquake at the SONGS l
site.
Dr. Idriss also developed a response spectrum to be associated with his study.
The response' spectrum was compared to the response spectrum for the DBE at SONGS and it was found that the DBE spectrum exceeded at all periods the 84th percentile instrumental spectrum calculated by Dr.
l Idriss at all periods (FF Nos. 233-238).
12 i
O In addition to Applicants' studies, the USGS has also published documents attempting to predict values of PGA for various size earthquakes.
The most recent of such documents available at the time of hearing was Open-File Report 81-365 by Drs. Boore and Joyner.
Dr. Boore appeared as a subp oened witness during the hearing and testified concerning Open-File Report 81-365 in its most revised version, an article submitted to the Bulletin of the Seismological Society of America (BSSA).
The data base used in that document is somewhat broader than has been used by Applicants' consultants, extending to recordings'from greater distances with lower PGAs.
Open-File Report 81-365 assumed that all earthquakes have the same shape attenuation curves and did not include magnitude saturation.
With respect to magnitude saturation, Dr. Boore stated it was excluded as a philosophical point, that it minimized the number of parameters to be dealt with in the analysis but that as more data becomes available, he expected PGA to be shown to saturate with magnitude.' The subject of saturation of PGA was discussed by a number of the witnesses I
in the proceeding.
There was general agreement between such i
witnesses that saturation is a real, frequency-dependent l
l physical process affecting various peak measurements in seiamology.
The area of contention in this proceeding was the point at which PGA became effectively independent of i
increasing magnitude.
FOE's witness, Dr. James N. B rune,
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contended that there was insufficient near-field strong ground motion data to conclusively prove saturation of PGA.
Dr. Brune generally supported the fact of saturation except where it was applied to saturation of PGA.
Each of Applicants' witnesses ehowed the data to be magnitude dependent with respect to PGA and incorporated magnitude saturation in their analysis.
As previously stated, Dr.
Boore declined to include saturation as a factor in his Open-File Report 81-365 but freely admitted that it probably was a valid consideration.
The validity of this consideration was also addressed by A'plicants' rebuttal p
witness Dr. Kenneth W. Campbell who testified that there was a 95% statistical confidence level that magnitude saturation exists (FF Nos. 239-250; 290-300).
In any event, the predictions from Open-File Report 81-365 are compatible with those of Applicants' consultants and when used in an appropriate manner predict values less than the.67g for SONGS 2 & 3.
When data beyond 50 km is excluded and the values of 81-365 are reduced to account for both components of horizontal motion, for an M 7 event 8 km s
from a site, the predicted mean and 84th percentile values for PGA are.31g and.57g, respectively (FF No. 1451.
(4)
Earthquake Modeling Dr. Gerald A.
Frazier performed modeling studies for SONGS that were intended to complement empirical studies performed by Mr. Wight and Dr. Idriss.
The basic objective 14
l
)
of the modeling studies is to predict ground motions at the SONGS site that would result from a large earthquake hypothesized te occur along the OZD.
Such modeling is accepted as having great potential for predicting strong ground motions at particular sites.
Dr. Frazier's model uses both the " forward" and
" inverse" methods to arrive at his pred.ctions (Infra, pp.
40-41).
The parameters used in his modeling characterize a specific fault slippage along a specific rupture surface in a specific earth structure.
This requires characterization of rupture kinematics, rupture extent and orientation relative to the site and geologic structure.
Considerable effort hos gone into the assignment of values for these parameters and was described in detail.
The modeling studies have undergone considerable review.
As a result of the pioneering nature of the modeling there has been generated considerable interest and comment.
The two primary commentators in this proceeding were Dr. Brune and Dr.
J.
Enrique Luco.
Both Dr. Brune and Dr. Luco appeared to criticize that their particular areas of interest were not adequately covered by Dr. Frazier's mode'ing.
The thrust of Dr. Brune's testimony throughout the proceeding was that Applicants had not allowed for all
" possibilities" in their assessment of the seismic design basis for SONGS.
This theory carried over into his criticism of Dr. Frazier's modeling and his essential complaint was 15
that as defined, the modeling would not allow for the types of possibilities he felt could occur in an actual earthquake.
It muut be noted that the " possibilities" advocated by Dr. Brune have in fact never been experienced in real earthquakes.
Neverthelese, Dr. Brune would argue th: a model should allow for such possibilities before it is acceptable to him.
Dr. Luco criticized the value of the attentuation factor "Q".
His criticiam was that the value of Q had not been adequately investigated.
Dr. Luco does not know of any better value and, in fact, adopts Dr. Frazier's value of Q for his own ctudies, then ' simply doubles it for some arbitrary undisclcsed reason.
Dr. Luco also criticized that the results of the modeling were off by a factor of 2.
On cross-examination, Dr. Luco's generalization could not be validated when actually compared to predictions at distances near 8 km compared to actual recordings for the 1979 Imperial Valley earthquake.
When the model is applied to SONGS, assuming an M 7 s
and rupture orientation so as to maximize ground motion at SONGS, the resdits indicate the design spectrum of SONGS 2 &
3 is conservative in that it exceeds the predicted instrumental spectrum at all periods of interest using 2%
damping (FF Nos. 251-264).
(5)
Additional Conservatisms of the SONGS DBE In addition to considering the empirical studies and the modeling studies, the manner ir. which the DBE 16 r
P spectrum was developed and has been used, adds considerable conservatism to the SONGS DBE.
Dr. Robert L. McNeill testified concerning the development of the DBE spectrum for SONGS 2 & 3 and pointed out that it wa, derived in an extremely conservative manner and in fact increased from.5g to.67g for the sole purpose of adding an extra conse rvati sta.
Further, the DBE developed for SONGS 2 & 3 was an instrumental spectrum as opposed to a generally lower design spectrum normally used for the desicn of a facility.
The fact that the DBE cpectrum was used directly for design probably represents the greatest cons'erva tism in the construction of the plant (EF Nos. 265-271).
A further consideration reflecting the conaervatism of the design spectrum is that credit for coil-etructure interaction was not taken at SONGS 2 & 3.
As discussed by Dr. McNeill, this factor adds considerable additional conservatism te the SONGS DBE design spectrum (FF Nos.
265-281).
Additional elements adding conservatism to the DBE spectrum are construction practices, i.e.,
the use of larger structural members then specified in design, the final strength of materials such as concrete, and the nonlinear strengths of the materials used (FF No. 282).
The DBE spectrum itself, which was used for desigr.
is not a design spectrum in the normal sense.
As previously stated, SONGS 2 & 3 has conservatively applied the free-field 17
instrumental cpectrum developed for SONGS 2 & 3 directly to l
its design.
This is approximately 1.5 to 2 times the appropriate design spectrum (FF Nos. 283-285).
Finally, on a statistical basis the probabil.ty of exceedance of a free-field PGA of.67g at SONGS is less than 10-4 The annual probability of exceeding the instrumental form of the SONGS DBE is less than 10-5 and more likely 10-6 (FF Nos.
286-287).
(6)
Conclu,sions Regarding Adequacy Of DBE Applicants submit that the lines of evidance supporting the conservatism and adequhey of the design basis for SONGS 2 & 3 are not only overwhelming from a purely technical standpoint, but are in large part uncontroverted on the record.
NRC Staff supported the conclusions reached by Applicants and Intervenors offered no evidence controverting the conclusions reached.
Intervenor witness Dr. Brune and Board witness Dr. Luco expressly declined to express an opinion on the adequacy of the seismic design basis.
The various lines of evidence suppor ting the adequacy of the DBE are set forth in the proposed Findings of Fact 324-338.
B.
Issue #3:
Whether the seismic design basis for SONGS 2 &
3 is inadequate to protect the public health and safety as a result of discoveries subsequent to issuance of the construction 18
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permit of the following geologic features:
(1)
ABCD features at the site; (2)
Features located at Trail 6, Target Canyon, Dead Dog Canyon, Horno Canyon, and " onshore faults E and F";
(3)
Such other features as the parties may agree are. relevant to the seismology of the SONGS site or with respect to which Intervenor, Friends of the Earth, makes a threshold showing of relevance.
The testimony and exhibits 'of Applicants' witnesses Mr. Jay L. Smith and Dr. Perry L.
Ehlig and NRC Staff witness, Mr. A. Thomas Cardone, conclusively demonstrated that the geologic features discovered subsequent to the issuance of the construction permit: (a) were the subject of detailed and extensive investigations; (b) are not significant to the SONGS site; and (c) do not render the seismic design basis for SONGS 2 and 3 inadequate to protect the public health and safety.
FOE did not address nor attempt to address any geologic features other than those identified in the stated issue.
FOE presented direct testimony on only one of the identified items, the ABCD features.
(cf. Testimony of Mark R.
Legg.)
The Applicants' and Staff's evidence on the lack of aignificance of the other features is uncontroverted.
19
(1)
ABCD Features The ABCD features were discovered during site excavation and were extensively investigated during the period May, 1974 to February, 1978.
These invstigations involved hundreds of man-days by several investigators including members of the NRC and USGS Staff.
Three reports on the ABCD features were also prepared and submitted to the NRC Staff for its review during the period 1974-1976.
(Applicants' Exhibits #25,JLS-1, #26,JLS-2, and #27,JLS-3; '2F Nos. 345-362.)
FOE offered no direct evidence challenging the adequacy or level of Applicants' investigations of these features.
Several questions regarding the adequacy of the investigations of these features were directed to Mr. Smith, Dr. Ehlig, and Mr. Cardone on cross-examination.
- However, these questions failed to elicit any evidence which demonstrated that the Applicants failed to conduct the necessary investigations such that the health and safety of the public might be jeopardized.
Mr. Smith, Dr. Ehlig, and Mr. Cardone reaffirmed the thoroughness and completeness of the investigations of these features during cross-examination.
(Tr. 2656-2781; 2898-2951; 6620-6746)
FOE also attempted to challenge the Applicants' and Staff's conclusion that the ABCD features are not " capable faults" as defined by 10 C.F.R.,
Part 100, Appendix A,Section III(g), and thus are not significant to the safety of 20
the SONGS site.
The only direct evidence FOE introduced on the issue came from the testimony of Mark Legg regarding the ABCD features.
Mr. Legg postulated that the ABCD features "are favorably oriented for slip and release of stress under the present stress regime therefore [ making it) possible that any or all of these features (faults) may slip in future earthquakes under the present tectonic style" (cf. M. Legg, Written Testimony following Tr. 5213 at pp. 8-10).
In evaluating the weight to be accorded Mr. Legg's testimony, it should be noted that: (1) he has not obtained any degree in geology (Tr. 5149); (2)*he has not done any onshore geologic work in the San Onofre area (Tr. 5156); (3) he has not done any field studies with respect to the SONGS licensing proceeding (TR. 5156); (4) he is not professionally competent to conduct onshore geological studies of the site (Tr. 5168); (5) he is basically more a geophysicist than a geologist and does not have much qualification as a geologist (Tr. 5172-73); (6) he has driven past the SONGS site but he has never been there specifically to look at any geologic
- feature, e.g.,
he has never even seen the Cristianitos fault (Tr. 5174); (7) he has never studied the geology of the ABCD features but has only read the report describing the ABCD features (Tr. 5252); and (8) he has never conducted any field examination of the ABCD features (Tr. 5252).
Applicants' and Staff's witnesses, on the other hand, are highly qualified and experienced geologists who 21
have examined in the field, explored and documented the ABCD features in detail.
(J. Smith, Written Testimony, Issue #4, pp. 1-7 (Tr. 888-894); Ehlig, Written Testimony, Issue #4, pp. 1-3 (ff. Tr. 941); Cardone, ff. Tr. 5560)
Applicants' and Staff's testimony and exhibits regarding the ABCD features are neither speculative nor misleading.
The preponderance of the evidence presented by Applicants and Staff, which is essentially uncontroverted, demonstrate that:
(a)
The ABCD features are joints displaying small amounts of mutual shear displace ~ ment; they are not capable faults; they are of such small scale as to go unnoticed in general mapping of the region; and they are clearly older than 130,000 years.
(b)
The ABCD features have no characteristics that would permit associating them with seismicity or to known faults, such as the Cristianitos, the OZD, or any projections of the postulated CZD.
They are not surface expressions of a deepseated shear zone nor are they a surface manifestation of some as yet unknown fault or zone of deformation beneath the San Mateo formation; (c)
The ABC features formed in response to small amounts of horizontal regional compression acting on relatively homogeneous sandstone, the D features formed during a time of reduced overburden pressures.
22
(d)
The ABCD features formed under stress conditions different from those that produced the Cristianitos fault, and the distribution of A and B features in the site re93on indicates that the features are independent of the effects of either the Cristianitos fault or stress release due to erosion along the seacliffs (FF Nos. 367-439).
Based on the overwhelming weight of the evidence, the ABCD features must be found not to be capable faults as defined by 10 C.F.R.,
Part 100, Appendix A, and not significant to the safety of SONGS (FF Nos. 440-442).
(2)
Trail 6 Offsets Small vertical offsets of the contact between the bedrock and marine terrace deposits of the stage 5e platform were found in 1977 in the seacliff approximately 3 miles south of SONGS.
The evidence is uncontroverted that the offsets are of landslide origin and of no significance to the SONGS site (FF Nos. 443-447).
(3)
Features at Horno and Dead Dog Canyon Offsets of the 125,000 year-old bedrock / marine terrace contact were discovered near the mouths of Horno and Dead Dog Canyons, about 5 miles southeast of SONGS.
Once again, the evidence ir uncontroverted that the offsets were caused by landsliding and are of no significance to SONGS (EF Nos. 448-450).
23
(4)
Target Canyon Offsets of the stage Se platform were observed at Target Canyon, a distance in excess of 5 miles from the site.
The evidence favors a nontectonic origin.
The offsets are small, tens of thousands of years old and have a different orientation fr, most faults in the region.
A projection of these features would be tangent to a five-mile radius around this site.
The features are not significant to the site (FF Nos. 451-456).
(5)
Onshore Faults E and F Fault E lies about 500 to 5,000 feet cast of the Cristianitos fault, on the south flank of the San Onofre mountains.
Fault F is about 2,000 feet east of Fault E.
Both faults are nearly parallel to the Oristianitos fault.
Beneath the surface the faults dip steeply toward each other.
Neither fault is connected to the Cristianitos fault nor do they form a " fault zone" with the Cristianitos.
The faults are most likely 4 to 10 million years old and were formed in an east-west extensional tectonic regime.
The faults have experienced no movement for the past several hundred thousand years.
They are not capable and are not significant to SONGS (FF Nos. 457-465).
In sum, the record reflects uncontroverted evidence in support of the conclusions set forth in the testimony and exhibits of Applicants' witnesses, Mr. Jay L.
Smith and Dr.
Perry L.
Ehlig, the testimony of Staff witnesses, Mr. T.
24 l
Cardone, and the Staff Safety Evaluation Report.
The discovery of the above-referenced geologic features subsequent to the issuance of the construction permit resulted in extensive geologic mapping of the SONGS site and vicinity, review of geologic literature of the site and its region, analyses of aerial photographs, excavations of exploratory trenches, drilling of borings, detailed logging of all excavations, petrographic laboratory examinations, and theoretical analyses.
The investigation of these geologic features was performed by qualified experts for the Applicants and Staff for the purpose bf analyzing in detail tha characteristics of the features, determining their age and origin, interpreting their structural relationships, and evaluating their significance to SONGS.
The conclusion reached is that the seismic design basis for SONGS 2 & 3 is not rendered inadquate to protect the public health and safety as a result of the discovery of these geologic features subsequent to issuance of the construction permit.
C.
Issue #2:
Whether characterization of certain offshore f
geologic features as a zone of deformation, i
referred to as the Cristianitos Zone of Deformation (CZD), or whether any additional.
information about the CZD which became 25 l
available subsequent to issuance of the construction permit render the seismic design basis for SONGS 2 & 3 inadequate to protect the public health and safety.
(1)
==
Introduction:==
History and Level of Investigation of Area Offshore SONGS Issue #2 arose primarily as the result of a report issued by Staff witnesses, Dr. H. Gary Greene of the United Statea Geological Survey ("USGS") and Dr. Michael P.
Kennedy of the California Division of Mines and Geology (see Staff Exhibit #7, Safety Evaluation Report,* Appendix F and Appendix G,
pp. G G-li).
Applicants' witness Dr. David G. Moore presented the greater portion of Applicants' evidence on Issue #2.
His testimony began with a description of the history and level of investigations that ). ave been conducted offshore SONGS since the late 1960's.
More than 2500 km of seismic reflection transects have been utilized by the Applicants during the past twenty years to investigate the offshore geology of SONGS, ard altogether the geophysical studies of the offshore geologic structures have extended for more than 100 km to the northwest and southeast of the plant site and seaward across the shelf to the deep basins of the southern Caliiornia Continental Borderland (FF Nos. 470-474).
The most detailed of tha geophysical investigations were conducted close to SONGS, with most transects confined i
26
to a 15 km by 30 km area on the centinental shelf which parailels the coastline between San Mateo Point and Oceanside (the San Onofre Shelf) -- an area which includes Greene and Kennedy's so-called CZD (see Figure DGM-C; FF No. 474).
With regard to the history of the offshore investigation, Dr. Moore's testimony conclusively demonstrated that these features " discovered" by Greene and Kennedy have, in fact, been well known to Applicants for some period of time (see Exhibit #36,DGM-L; FF No. 490).
- Indeed, Staff witness, Mr. James Devine, confirmed Dr. Moore's testimony, in response to a question 'from Acplicants, by stating that, in general, the features characterized by Greene and Kennedy as the CZD were certainly known to the people associated with the site for some peried of time before this designation as a CZD (Tr. 6115).
In addition, Mr. Devine recalled that these features were discussed back in the contruction permit days.
To the extent that Greene and Kennedy may have correlated one feature to another, Mr.
Devine felt that might constitute new work, but he concluded "that :he features themselves were identified quite some time ago, before the Greene and Kennedy study" (Tr. 6115).
With regard to
^te level of investigation of the area offshore SONGS, Dr. Greene testified that in his opinion there was no lack of general offshore data, that the track line spacing in th.s investigation is "the greatest density of track lines that he has ever dealt with as far as an 27 J
area of this size, [and that he had never] had the fortune to have this much data available to [him]"
(Tr. 2282).
Drs. Greene and Kennedy further explained why, in light of the great density of track lines and volume of data, they still chose to note some areas offshore SONGS as " data voids."
In response to a series of questions from Applicants, Dr. Greene stated that certain areas were marked
" data voids" because he and Dr. Kennedy subsequently determined that there were some problems with profile lines they couldn't use to identify what they were looking for.
They were not, however, complaining of a lack of geophysical profiles in these designated areas (Tr. 2283-84).
And as Dr.
Moore pointed out in his direct testimony, and as depicted in Applicants' Exhibit #42,DGM-1, some of the arens noted as
" data voids" are flanked by several seismic profiles cr are transe;ted by them (FF Nos. 496-498).
Although Drs. Moore, Kennedy, and Greene and Mr.
Devine reached similar conclusions regarding the history and level of investigation conducted offshore SONGS, the record reveals a difference of opinion regarding the interpretation of the offshore prcfiles and the significance that should be attached to the faults and folds depicted in these profiles.
Thic difference of opinion is due in large part to the different levelt and degree of analyses the parties engaged in in their respective investigations of the offshore area.
Dr. Noore's detailed examination and interpretation of the
". 8
very large amount of relatively close spaced seismic reflection pro. tiles provided enough information, in his expert opinion, to construct a map of the San Onofre Shelf and allow ir.terpretation of that area (which includes the so-called CZD) with a high degree of confidence.
Unlike FOE or the USGS, important aspects of offshore stratigraphy as well as the evolution of onshore etructures were also incorporated into Dr. Moore's analysis (FF No. 488-489).
F...
Legg, and Drs. Kennedy and Greene limited their investigations of the area under contention to a review of the offshore seismic profiles, i.e., in forming a basis for their opinions they only looked at geophysical indications of deformation in an area where the stratigraphy was unknown to them.
Drs. Kennedy and Greene agree that an analysis of the offshore stratigraphy and onshore geology (including stratigraphy and tectonic evolution) are critical to a comprehensive evaluation, but admit that such analyses were not part of their investigations (Tr. 2158-2161).
Thus, only Applicants, through the work of Dr. Moore, Dr. Ehlig and Dr.
Shlemon, performed what all the witnesses agree are the necessary investigations and analyses of the area under contention.
(2)
Interpretation of Offshore Profiles and Results of Offshore Investigations Dr. Moore's testimony included a thorough l
discussion of the science of seismic profiling; a description 29
and discussion of the area of interest offshore SONGS; identification of marine terraces and bedrock fermations which are significant for purposes of age dating geologic features whi.ch were studied in depth; and identification of the principal structural features beneath the San Onofre Shelf (Figure DGM-E).
The evidence shows that when the features within the San Onofre Shelf are contrasted with each other, *he predominant features within this area are those associated with the South Coast Offshore Zone of Deformation (SC0ZD) and those lying to the east of the SCOZD are the less prominent folds and relatively short discontinuous faults of the so-called CZD.
With respect to folding, the evidence demonstrated that the CZD is an area of rather gentle broad folding and is, with very few exceptions, of a much lesser amplitude and a very different character than the anticline and syncline associated with the San Onofre Shelf (see Figure DGM-E).
With respect to faulting on the San Onofre Shelf, the South Coast Offshore Fault (SCOF) is clearly the predominant feature and the apparent faulting in the CZD region appears to be largely interformational faulting associre.ted with or generated by the various folds.
Most of the faults do not extend deep into the section or upward to the seafloor or beyond the Pleistocene erosional unconformity.
" hey do not have the intensity or continuity comparable to the SCOF.
30
(3)
Postulated Connection of CZD with Cristianitos Fault and OZD a)
Cristianitos fault - CZD With regard to the evidence of a postulated connection between the Cristianitos fault as it is projected offshore, and the CZD, the record clearly demonstrates that the seismic lines closest to the offshore projection of the Cristianitos fault do not reveal any feature which could be interpreted as an extension of the Cristianitos beyond about f
2,000 meters (or 6,000 feet) from the shoreline.
The faults which do occur further along an approximate seaward projection and which Intervonors speculated might be the area of a possible connection are very deep in the section and much too old to be associated with the Cristianitos (FF No.
482).
As described by Dr. Ehlig and Dr. Mccre, the Crictlanitos fault was active between about 10 and 4 million years ago and the deep faults in the area of the CZD, approximately on a nossible projection of the Cristianitos, do not extend into sediments younger than older Monterey, thus demonstrating that they have been inactive for a period greatly predating activity on the Cristiar.itos fault.
t Furthermore, these faults are of oppesite displaceme'.t from that of the Cristianitos fault (downthrown to the east vs, downthrown to the rest).
The data, therefore, clearly indicates there is no significant seat ci extension of the l
31
Cristianitos fault and that its extension is no more than about 2,000 meters seaward along its onshore trend (FF Nos.
480-483; 517-520).
Further evidence of the absence of any possible connection or relationship between the CZD and the Cristianitos is as follows:
(i)
The group of folds and associated faults, which were assigned the name "Cristianitos Zone of deformation," lie midway between the onshore Cristianitos Fault and a projection of it to the OZD.
It cannot be implied that these structures are in any way related to the Cristianitos Fault because the seir;ni~c data doeu not support this implication. 'As Dr. Greene testified, this " zone" bears-the name "Cristianitos" only because it is common practice to name structural features after geographic locations and the folds and faults are located offshore but close by the Cristianitos fault.
Thus, the name of the zone is purely a geographic appellation and it is not intended to imply any relationship with the Cristianitos fault (Tr. 2139-40).
(ii)
The onshore Cristianitos fault is a discreet single trace normal fault with downthrown block to the west.
It is the result of east-west extension.
In contrast, the faults and folds'of the so-called CZD are compressional features.
Also, the faults of the CZD generally do not extend to any great depth in the section as would be expected of an extension of the Cristianitos fault (FF No. 481).
32
(iii)
Finally, though Drs. Greene and Kennedy chose to label the area FOE speculated might be the location of the postulated connection between the CZD and the Cristianitos as " data void," Applicants' Exhibit #36,DGM-L, Exhibit #38,DGM-N and Exhibit #42,DGM-1, as explained by Dr.
Moore, demonstrate that profile lines were run in the vicinity of this postulated connection (i.e., Marine Advisors S-26, Sonia 5 and Woodward Clyde 847 and 849) and that if a major fault were to project through this " data void" toward SONGS, these studies would almost certainly have shown it.
Thus, the designation of " data void" has no significance with regard to the postulated, but unproven, CZD-Cristianitos fault connection (FF Nos. 496-498).
b)
CZD -- OZD With regard to a postulated connection of the faults of the CZD and the SCOF (i.e.,
the OZD), Applicants recognize the southward projection of the CZD by Greene and Kennedy, but as tectified to by Dr. Moore, and depicted 11.
Figure DGM-E, Applicants' interpretation of the structure referred to as the CZD shows its nearest faulting on the central shelf to be approximately 10,000 feet or 3.6 km away from the SCOF when measured along a projection of the onshore Cristianitos Fault, and thus the Kennedy and Greene interpretation does not support a postulated connection j
between the SCOF and the CZD (FF No. 495).
33 l
i
Greene and Kennedy's postulated connection of the CZD and SCOF relies on the existence of a narrow band of fault ~ bounded deformation which trends southeast at an angle to the main body of folding in their CZD.
Dr. Moore's interpretation of the seismic data does not show this band of deformation but instead shows it as being related to a deeply buried small anticline.
Dr. Moore also interprets a nearby adjacent fault postulated in Greene and Kennedy's map (SER Appendix F, p.
F-24) as being a misinterpretation by them of seismic signal cross-overs on a relatively steep-sided flank on that portion of the San Onofre Shelf Syncline.
- Thus, Greene and Kennedy's postulated near connection (" merges with or is truncated by") of the alleged CZD with the OZD relies on questionable and difficult interpretations of the seismic reflection profile records (FF Nos. 493-494).
More important and more pertinent to the question of connection, however, is the age of any faulting or zone of deformation even aseuming that the CZD merges with or is truncated by the OZD.
The evidence demonstrate; that both the narrow band at the southern en:1 of the CZD and the alleged fault in the southwestern part of the San onofre Shelf Syncline (see Figure DGM-E) are overlain by strata of probable late Miocene age which is clearly unfaulted.
This is most significar,t since it demonstrates that there has been no movement on these faults for at least 5 to 6 million years (FF No. 493).
For this reason, the presence or absence of f
34 4
n
difficult to interpret features at depth in the seismic i
profiles depicted in the exhibits in evidence in this case and the issue of whether there is or is not a postulated I
connection between the OZD and the CZD, and if so, at what point does it occur, are rendered academic.
That is, what we are really concerned about in this case and, in particular, in Issue #2, is whether the postulated CZD is capable, either as an independent structure or as a result of relationship to a capable structure.
What the record shows is that the faults associated with the CZD are not capable and there is no reasonable expectation that movement on the OZD would be accompanied by movement on the CZD as defined by 10 C.F.R. Part 100, Appendix A.
Therefore, the questionable faults of the CZD really have no significance to the safety of the SONGS site.
1 (4)
Age of CZD Applicants investigations, as discussed above, not only included a determination of the regional and local l
stratigraphy of the offshore area and the structure of this i
area, but also involved an evaluation and assignment of the ages of the various features.
These investigations were conducted for Applicants by Dr. Roy J. Shlemon.
Dr.
Shlemon's conclusions were uncontroverted by FOE and fully supported by Staff at the hearing.
Those conclusions which are most significant to Issue #2 are as follows:
35
(i)
Dr. Shlemon investigated the broad chronological framework of the entire San Onofre region, on land and offshore in order to extrapolate and determine the age of the features offshore.
The results of these investigations, which are contained in Applicants' Exhibits
- 28,RJS-1, #29,RJS-2, and #30,RJS-3 show the Quaternary stratigraphy in the San Onofre area to be rather remarkable and perhaps the best exposed on the entire west coast of the United States (FF No. 500);
(ii)
Wave cut platforms offshore SONGS range in age from 5,000 to possibly 80,000 years cid based on association with the marine isotope etage chronology and on stratigraphic relationship to overlying marine sediments dusted by radiocarbon.
Neither the offshore platforms nor overlying sediments are displaced by the so-called CED (FF No. 521);
(iii)
Fluvial terraces bordering San Onore and San Mateo Creeks, in the order of 60,000 years old, are traceable from the coastline some 2 or 3 miles upstream and within the resolution of field measurements.
These terraces are not displaced by any onshore projection of the so-called CZD (FF No. 524); and i
(iv)
There is no observable evidence for displacement of the 125,000-year-old onshore marine platform, the 60,000-year-old fluvial terrace, or the underlying Tertiary bedrock (San Mateo formation) in areas adjacent to i
36
SONGS where the so-called CZD might be projected onshore (FF No. 525).
(5)
Conclusions Applicants submit that the evidence in this proceeding warrants the following conclusions with regard to Issue #2:
(1)
Applicants detailed examination of the area offshore SONGS provide sufficient information to construct a map of the San Onofre Shelf and allow interpretation of this area with a high degree of confidence.
Important aspects of offshore stratigraphy, evolution of chshore structures, as well as the age of various features onshore and offshore SONGS were also incorporated intc Applicants' analysis in order to present the most complete, comprehensive, and accurate depiction of this area.
(2)
The geologic features
- discovered" by Greene and Kennedy do not constitute new discoveries of geologic features.
These features have been well known to Applicants and NRC Staff as far back as 1969-1970 (Applicants' Exhibit
- 36,DGM-L).
l l
(3)
The presence of these folds and faults, although lying coincidente
' rom a geographic standing, are not so related as to form a - oone" or any other structure capable of generating an earthquake.
These folds and faults lie east of the South Coast Offshore Zone of Deformation 37 L
(SCOZD) -- the predominant feature in the area offshore SONGS and a part of the assumed OZD -- and consist of less prominent folds and relatively short discontinuous faults.
In addition, the various faults within the so-called CZD are associated with structural formations of very old and very different ages (FF No. 475-479).
(4)
Even if these features are characterized as a zone, they do not connect with or have a structural relationship with the onshore Cristianitos fault.
(5)
Based on the location and age of the onshore and offshore terrace platforms and th&ir related deposits in the San Onofre area, as well as on extensive exposures of the San Mateo formation, there is no evidence of the CZD extending onshore at San Onofre, i.e. no evidence has been observed for displacement of the 125,000-year-old marine platform, the 60,000-year-old fluvial terrace, or the underlying Tertiary bedrock (San Mateo formation, 4-10 million years old) in areas adjacent to SONGS where the CZD might be projected onshore; and neither the offshore platforms (which range in age from about 5,000 to possibly l
80,000 years old) nor overlying sediments are displaced by the CZD.
(6)
The folds and faults characterized as the CZD also do not connect or have a structural relationship with the Offshore Zone of Deformation (OZD).
Even if one assumes the CZD " merges with or is truncated by the OZD" (Safety l
Sa 7
Evaluation Report, Appendix G, p. G-ll) the CZD is still not a capable fault because 10 C.F.R. Part 100, Appendix A requires that in the case of a fault having a structural relationship to a known capable fault, there must be a reasonable expectation that movement on the one, will be
(
accompanied by movement on the other.
Movements on the OZD for at least the past 120,000 years have not been accompanied by movement on the CZD (Safety Evaluation Report, Section 2.5.1.12).
(7)
Neither characterization of certain offshore features as a zone of deformation or 'any additional information about this zone of deformation which became available subsequent to the construction permit renders the seismic design basis for SONGS 2 & 3 inadequate to protect the public health and safety.
D.
Issue #1 Whether as a result of ground motion analysis techniques developed subsequent to issuance of the construction permit or data gathered from earthquakes'which occurred subs 3quent to l
issuance of the construction permit, the seismic design basis for SONGS 2 & 3 is inadequate to protect the public health and safety.
39
s Applicants' testimony on Issue #1 was of two general types: first, an assessment of advances in theoretical approaches to the study of earthquake motion, and second, an investigation of particular relevant earthquakes that have occurred since issuance of the construction permit.
The testimony discussed both a " forward," and
" inverse" approach to theoretical advances in analysis of earthquake ground motion.
The " forward" method involves the evolution of a shear crack from its initial fracture through its growth (or spreading phase) to its eventual termination.
Such models are highly idealized but still provide useful information on various aspects of earthquake physics.
Its use at the present time is limited to examination of low-frequency (less than 1 Hz) properties of earthquake fractures.
The " inverse" method relies on observational data (principally ground motion recordings) to determine what happened in a fracture zone.
Again, this approach is limited to low frequencies (below 1 Hz).
Both approaches have become available only because of recent advances on large digital computers that now allow appraisal of various hypothesized conclusions (Frazier, Written Testimony, pp. 1-6) (ff. Tr.
941).
Applicants sponsored modeling which combined both the forward and inverse methods by adjusting results from simultations of idealized cracks so that tney are consistent I
40
with actual recorded motions.
This was then applied to the SONGS site to estimate site specific ground motions for postulated future earthquakes.
Such modeling demonstrated the conservatism of the empirically derived spectra and particularly the DBE (FF Mos. 529-535).
In addition to numerical modelling, Applicants undertook comprehensive investigations of eartnquake effects using current earthquake theory and recordings.
Such empirical studies of earthquake recordings are unsurpassed for purposes of evaluating the seismic criteria used for SONGS (FF No. 527).
Both the empirical studies and the modeling support the conclusion that the SONGS 2 & 3 DBE high frequency anchor point (0.67g) and design spectrum are conservative (FF Nos.
528; 536).
Applicants presented testimony on earthquakee that have occurred since isauance of the construction permit.
Six selected earthquakes were examined in detail to confirm the current adequacy of the DBE.
The particular events, which occurred in Imperial Valley, California, Iran, Russia, Baja
(
California, Italy and Mammoth Lakes, California were l
l appropriately scaled for the assumed conditions at SONGS 2 &
3 (M 7, Distance 8 km) and values were calculated for PGA.
s None of the scaled values exceed the Zero Period Acceleration l
("ZPA") of the SONGS 2 & 3 DBE.
Their average was about l
l 41
~
40% - 50% of the SONGS ZPA, thus demonstrating the conservatism of the SONGS DBE (FF Nos. 537-542).
The precise studies of the Imperial Valley and Mammoth Lakes earthquakes, both as to their horizontal and vertical components are discussed in Findings of Fact Nos.
543-557.
These studies again demonstrate the adequacy of the SONGS 2 & 3 seismic design basis.
One of the important general conclusions to be drawn from recent history is that as more data becomes available, past projections are being confirmed and predicted values are decreasing (FF Nos. 538; 558).
In addition to studies of large earthquakes generally, Applicants studied and presented testimony on two smaller events that occurred in 1975 approximately 20 km from SONGS and another five small earthquakes that occurred between June 29 and July 1, 1977 about 2.5 cm north of the 1975 events.
Because of the relative closeness of the events to the Cristianitos fault, an extensive investigation was conducted.
A refined crustal model was developed to more accurately locate and study the subject events.
As a result of these studies it was concluded, and the evidence demonstrates that the 1977 cluster and 1975 events were 4
associated with each other and with the alignment of the northeasterly trending Trabuco Canyon and not with the Cristianitos fault (FF Nos. 559-568).
42
e III CONCLUSION It is submi
.2at Applicants' case on the above four issues is compis _ and conclusive.
The inescapable conclusion based on the totality of the-record is that the seismic design basis for SONGS 2 & 3 has not been rendered inadequate to protect the public health and safety as a result of new discoveries, analyses, or information gathered on the seismology and geology of the SONGS region since the issuance of the construction permit, and, in fact, the seismic design basis for SONGS 2 & 3 'is exceedingly conservative such that the issuance of a fuel load and full 4
'43
____--______________________-_-__-_a
o power license will not be inimical to the common defense and security or to the health and safety of the public.
Dated: -September 11, 1981.
Respectfully submitted, DAVID R.
PIGOTT EDWARD B.
ROGIN SAMUEL B. CASEY JOHN A. MENDEZ Of ORRICK, HEERINGTON & SUTCLIFFE A Professional Corporation CHARLES R.
KOCHER JAMES A. BEOLETTO SOUTHERN CALIFORNIA EDISON COMPANY Attorneys for Applicants SOUTHERN CALIFORNIA EDISON COMP %IY and SAN DIEGO GAS & ELECTRIC COMPANY MVID R. PIG 0U By David R, Pigott JuMN A. MENDEZ By John A. Mendez l
l 44 i
l
e e
1 PROOP OF SERVICE'BY MAIL 2
I declare that:
3 I am employed in the City and County of San 4
Francisco, California.
I am over the age of eighteen years and not a party to the within entitled action; my business address is 600 7
Montgomery Street, 10th Floor, San Francisco, California 94111.
9 On September 11, 1981, I served the attached APPLICANTS' BRIEF IN SUPPORT OF PROPOSED FINDINGS OF FACT AND CONCLUSIONS OF LAW ON GEOLOGY / SEISMOLOGY ISSUES, in said cause, by placing a true copy thereof enclosed in the g
United States mail at San Francisco, California addressed g
as follows: (except where indicated by *)
16 James-L. Kelley, Chairman Robert Dietch, Vice President Administrative Judge Southern California Edison-17 Atomic Safety and Licensing Compar.y Bohrd P.
O. Box 800 18 U.S.
Nuclear Regulatory 2244 Walnut Grove Avenue Commission Rosemead, CA 91770 19 Washington, D.
C.
20555 20 Dr. Cadet H.
Hand, Jr.
Alan R.
Matts, Esq.
Administrative Judge Rourke & Woodruff 21 c/o Bodega Marine Laboratory California First Bank Building University of California 10555 North Main Street
??
P.
O. Box 247 Santa Ana, CA 92701 Bodega Bay, CA 94923 23 Mrs. Elizabeth B. Johnson Lawrence J.
Chandler, Esq.
24 Administrative Judge Richard K. Hoefling, Esq.
Oak Ridge National Laboratory Donald F.
Hassell, Esq.
25 Oak Ridge, TN 37830 Nuclear Regulatory Comnission Office of the Executive 26 Legal Director Washington, D.
C. 20555
1 David W. Gilman Janice E. Kerro Esq.
Robert G.
Lacy J.
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2 San Diego Gas & Electric Lawrence Q. Garcia, Esq.
Company California Public Utilities 3
P. O. Box 1831 Connission
~
San Diego, CA 92112 5066 State Building 4
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Mr. Lloyd voi. Haden Atomic Safety and Licensing Board 2089 Foothill Drive U.S. Nuclear Regulatory Commission 6
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State Geologist 23521 Paseo de Valencia 11 Division of Mines and Geology Suite 308 1416 Ninth Street, Room 1341 Laguna Hills, CA 92653 12 Sacramento, CA 95814 13
- Richard J. Wharton, Esq.
Phyllis M.
Gallagher, Esq.
2660 San Marcos Avenue 1695 W.
Crescent Avenue I4 San Diego, CA 92104 Suite 222 Anaheim, CA 92801 16 17 18
~
19
/
) )
- .' n ;'
w 20 John A.
Mendez One of Counselfor Applicants SOUTHERM CALIFORMIA EDISON COMPANY 71 and SAN DIEGO GAS & ELFCTRIC CO.
22 23 24 25 26
- served by Federal Express i