ML19209A223
| ML19209A223 | |
| Person / Time | |
|---|---|
| Site: | Indian Point, Seabrook  |
| Issue date: | 09/06/1979 |
| From: | Buck J, Rosenthal A NRC ATOMIC SAFETY & LICENSING APPEAL PANEL (ASLAP) |
| To: | |
| Shared Package | |
| ML093380357 | List: |
| References | |
| NUDOCS 7910030178 | |
| Download: ML19209A223 (19) | |
Text
.'
UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSIO a
om ATOMIC SAFETY AND LICENSING APPEAL BOARD S
q$ $
1I b }$, C Alan S.
Rosenthal, Chairman p.
h Dr. John H. Buck efi Michael C. Farrar g
E >3x g
'b
.)
In the Matter of
)
)
PUBLIC SERVICE COMPANY OF
)
Docket Nos. 50-443 NEW HAMPSHIRE, e_t _a_l.
)
50-444
)
(Seabrook Station, Units 1 and 2)
)
)
September 6, 1979 Supplemental opinion of Mr. Rosenthal and Dr. Buck, in response to the August 3, 1979 dissenting opinion of Mr. Farrar:
The appeals in this proceeding brought to us the attack launched by the intervenor New England Coalition on Nuclear Pollution against the findings below (1) that the safe shutdown earthquake (SSE) for the Seabrook site had a maximum intensity of VIII (measured on the Modified Mercalli scale); and (2) that the NRC staff (supported by the U.S. Geological Survey) had justifiably assigned a value of 0.25g to the maximum vibra' tory ground motion (acceleration) which might result from such an earthquake.
As the Licensing Board's initial decision re-flects, 1/ the source of the findings was the testimony of a
_1/
LBP-76-26, 3 NRC 857, 868-71, 919-22 (1976).
1085 276 7910030l5ib
. number of witnesses presented by the app'icants and the staff.
(Without detailing the educational and vocational backgrounds of these witnesses, it is not disputed that they are highly qualified experts in fields germane to this seismic inquiry.)
According to the Coalition, however, the Licensing Board should have rejected their conclusions in favor of a finding of an intensity IX SSE and an acceleration value of 0.75g.
Each of the three essential reasons advanced by the Coalition for their disagreement with the Board below was fully considered in ALAB-422 and rejected.
6 NRC 33, 57-64.
We looked first at the claim that the Board was obliged to accept the view of the Coalition's witness Dr. Michael Chinnery, founded upon a probabilistic analysis which he had conducted, that the likelihood of an intensity IX earthquake at the Seabrook site is approximately 10 /yr. 2/
Upon an ap-praisal of the Chinnery analysis, we found it to be both techni-cally and crucially deficient.
Beyond that, because of certain unproven assumptions central to the utilization of his approach, we determined that resort to it could not be squared with the dictates of Appendix A to Part 100.
Id. at 57-60.
_2/
In other words, one chance in a thousand per annum.
1085 277
3-We then turned to the Coalition's second thesis -- that, for analysis purposes, the 1732 Montreal earthquake (assumed by all parties to have been an intensity IX event) should have been treated as though it had occurred at the Seabrook site.
We pointed out that, under the terms of Appendix A, the validity of this assertion hinged upon whether the earth-quake both had occurred in the tectonic province in which the Seabrook site is located and either (1) was incapable of being associated with any tectonic structure or (2) was as-sociated with a structure demonstrably akin to a structure near the Seabrook site.
Our reading of the evidence of record bearing upon the geology of the relevant areas persuaded us of the correctnegs of the conclusion of one of the staff witnesses (Dr. J. Carl Stepp, the then Chief of thc Geo-sciences Branch in the Office of Nuclear Reactor Regulation) d!
that Montreal and Seabrook are in different tectonic provinces and that the 1732 earthquake is capable of being associated with a group of tectonic structures which are markedly dis-similar to the structures in the New Hampshire-White Mountain zone (which embraces the Seabrook site'.
6 NRC at 60-62.
=
_3/
See Tr. 11912-15; 11953-55.
1085 278
. Finally, we examined the sharp disagreement between, on the one hand, the Coalition's witness (Dr. Mihailo Trifunac) and, on the other, the staff's and the applicants' witnesses with respect to the maximum acceleration which might result from an intensity VIII earthquake at the Seabrook site.
Our evaluation of the evidence led us to determine that the 0.25g value concurred in by all of the experts other than Dr. Trifunac was sufficiently conserva-tive.
Id. at 62-64.
Mr. Farrar takes issue with each of the seismic con-clusions we reached in ALAB-422.
Although merely outlining the foundation for his divergent views at the time that decision was rendered (6 NRC at 111-13), as then promised he has now filed a considerably more detailed exposition of those views. A/
On a consideration of Mr. Farrar's full opinion, we adhere to our previously announced determinations.
Although no useful purpose would appear to be served by a full re-hearsal of what was said by us in ALAB-422, a brief response
_4/
Mr. Farrar's recent opinion also elaborates upon the extent of his disagreement with ALAB-436, 6 NRC 547 (1977), rendered in the special seismic proceeding conducted by a differently constituted appeal board in connection with the site of the Indian Point reac-tors.
The Indian Point majority are today filing a separate supplemental opinion of their own.
See 10 NRC at 1085 279
5-to some of the points made by our dissenting colleague might prove of assistance to the Commission should it elect to examine the seismic controversy itself.
1.
To begin with, M,r. Farrar maintains that we have applied an impelaissible standard in our treatment of the conflicting conclusions of the expert witnesses who testified on the seismic intensity and ground acceleration questions.
As he sees it, "because of the relative dearth of scientific knowledge about earthquake causation", neither the applicants and the staff nor the intervenors were able to establish the correctness of their respective positions on those questions.
According to Mr. Farrar, in such circumstances we should have decided the dispute in the intervenors' favor rather than, as he insists was done, ruled against them on the ground that they had the burden of persuasion and had failed to carry it.
10 NRC at (dissenting opinion, pp. 4-5).
There is not a jot or syllable in ALAB-422 which lends support to this characterization of our approach.
True, we did not there discuss at length the bases assigned by the staff and applicant witnesses for their ultimate conclusions on the seismic questions.
This was not, however, because of any misguided belief that the burden of persuasion on those 1085 280
. questions rested with the intervenors.
Rather, it was be-cause we were not confronted on appeal with any serious attack upon the underpinnings of the evidence of the staff and applicants; i.e.,
it was not cic.imed that either the data base or methodology utilized by those parties' wit-nesses was fatally infirm.
What we were told by the Coalition was something quite different:
in essence, that the contrary seismic conclusions of its witnesses (Drs.
Chinnery and Trifunac) were equally tenable and thus should have been accepted by the Licensing Board in preference to those of the other testifying experts.
In these circumstances, the appellate issue boiled down to whether the Coalition was right about that or whether, instead (as both the staff and the applicants asserted), the Coalition's evidence was not equally tenable and, accordingly, the Board below had not erred in refusing to adopt that in-tervenor's proposed findings on the seismic issues.
And it was that issue which we addressed and decided.
Notwithstanding his insistence that the staff and appli-cants had failed to prove their case on the seismic questions, Mr. Farrar's lengthy opinion is singularly devoid of any analytic consideration of the basis upon which their experts 1085 281
. had reached the conclusion that an intensity VIII should be assigned to the ~
- 7..
To the contrary, our dissenting colleague contents himself with an exposition of the rea-sons why he would accept the Coalition's proposition that its evidence on the intensity question was credible enough to have required the Licensing Board to mandate, in the interests of safety, a more conservative seismic design.
On the ground acceleration question, Mr. Farrar fin.ds him-self in agreement with the approach of none of the parties; in his view, the regulations require a still different type of analysis, as yet unperformed.
In short, as we see it, no genuine burden of persua-sion question is. presented by either the Coalition's appeal or ALAB-422.
The real difference between ourselves and Mr. Farrar centers upon (1) whether the Coalition pointed to any disclosures of record which dictated -- as a matter of fact, law, or policy -- that the Board below reject the expert conclusions of staff and applicant witnesses;-5/
--5/
Our dissenting colleague does comment unfavorably upon certain aspects of Appendix A, and more particularly the use it makes of the " tectonic province" concept.
10 NRC at (dissenting opinion, pp. 5-6).
As he implicitly recognizes, however, as long as the Appen-dix remains unaltered the staff and the applicants can not be faulted for conducting their analyses in accord-ance with its terms.
Nevertheless, we share his view that the Appendix warrants the closest reexamination (FOOTNOTE CONTINUED ON NEXT PAGE) 1085 282
_g-and (2) whether the ground acceleration associated with an intensity VIII earthquake was ascertained in a legally per-missible manner.
2.
Insofar as the neismic intensity question is con-cerned, Mr. Farrar concerns himself principally with the testimony of Dr. Chinnery. 5!
As r~;viously observed, in ALAB-422 we determined that the probabilistic analysis em-ployed by that witness was both technically deficient and inconsistent with the terms of Appendix A to 10 CFR Part 100.
6 NRC at 57-(0.
Mr. Farrar disagrees on both scores, a.
As noted in ALAB-422, Dr. Chinnery predicated his entire analysis upon the assumption that the recorded earth-quake experience-in two other areas of _he country -- the southeastern United States and the Mississippi Valley -- is instructive in determining the likelihood of the occurrence in New England of an earthquake of a particular intensity.
_/
FOOTNOTE CONTINUED FROM PREVIOUS PAGE 5
and, most likely, substantial revision.
See the dis-cussion in Indian Point, ALAB-436, supra fn.
4, 6 NRC at 574-77 (cited by Mr. Farrar).
We strongly urge the Commission to direct the staff to embark upon that mis-sion on a priority basis.
_6/
Mr. Farrar stresses Dr. Chinnery's educational and vo-cational credentials.
Although we do not pause to de-tail the background of the staff and applicant witnesses, their expe rt qualifications are no less ir.:pressive.
1085 283
. This assumption did not rest to any extent, however, upon the fruits of a comparison of the geology of the three areas.
In Dr. Chinnery's apparent view, such a comparison was un-necessary in light of his underlying hypothesis that, to quote Mr. Farrar, "the frequency of large earthquakes in any given area is directly related to the frequency of smaller earthquakes" in that same area. 2/
If Dr. Chinnery believed that hypothesis to have uni-versal validity, it is difficult to understand why he explic-itly declined to include the California earthquake experience in his probabilistic analysis -- offering as his reason for not doing so certain perceived dissimilarities between the California seismic situation and that of New England:
(1) that the California region is located near a plate boundary; and (2) that California earthquakes have a much larger source volume than do New England earthquakes (Tr.
4022, 4024).
Be that as it may, we have neither found nor been pointed to disclosures in the record which furnish any conceivable technical support for the proposition that the Mississippi Valley or southeastern United States experience may be applied to New England automatically (i.e., without
_2/
See 10 NRC at (dissenting opinion, p.
- 25) (empha-sis supplied).
1085 284
. regard to any geological dissimilarities which might exist).
In this connection, although none of these regions may be close to a plate boundary (as is California), nevertheless there is at least one major difference between New England, on the one hand, and the Mississippi Valley and the south-eastern United States, on the other:
tra frequency of earthquakes in the latter two regions is about the same but exceeds by an order of magnitude the earthquake frequency in New England.
See 6 NRC at 58, fn. 28.
To be sure, Dr.
Chinnery may net deem that difference to be of possible significance (in contrast to the matter of the location of plate boundaries).
But no explanation was offered as to why not.
Further, it might well have been that, had Dr. Chinnery expended the time necessary to explore the available litera-ture pertaining to the geology of the areas concerned, he would have uncovered other respects in which the Mississippi Valley and southeastern regions are similar to each other but different from New England -- thereby bringing into still greater doubt the justification for equating the three re-gions on the sole basis of a wholly unproven hypothesis. 8 /
--8/
Mr. Farrar suggests (10 NRC at fn. 44) the possi-bility that Dr. Chinnery "ha[d] been called upon to do his work in a very brief period just prior to his ap-pearance as a witness".
Although that may have been the case, it scarcely turnishes any reason to have con-fidence in either his hypothesis or his conclusions.
FOOTNOTE CONTINUED ON NEXT PAGE.
1085 285 In short, Mr. Farrar criticizes us for not giving cre-dence to a theory which rested upon nothing more than conjec-ture and which was offered by one who, from all that we can determine, did little to test the validity of that theory.
We think the criticism unwarranted.
We went on in ALAB-422 to take issue with the addi-tional assumption of Dr. Chinnery that the probabili'y curves plotted by him can be extrapolated linearly to higher'inten-sities.
6 NRC 58-9.
There is no apparent reason to expand at length upon what was there said on the point.
Suffice it to say that we remain persuaded that the assumption was technically unsound.
This is so not only for the reasons discussed in ALAB-422 but also because, in turn, the assump-tion seems to have rested -- and necessarily so -- upon the unsupportable premise that, no matter the characteristics of the geology in the New England area, there is no upper limit
--8/
FOOTNOTE CONTINUED FROM PREVIOUS PAGE Indeed, one might well question whether weight should ever be attached in an adjudicatory proceeding to theories advanced by a scientist who, no matter the reason, did not undertake the research necessary to enable him (or others) to pass an informed judgment upon the likely validity of his underlying assumptions.
1085 286 to the possible earthquake intensity in that area.
See, in this connection, Tr. Il934. S/
b.
Apart from its other difficulties (see fn.
5, supra), Appenlix A to 10 CFR Part 100 is not a model of clarity.
Nonetheless, due reflection upon Mr. Farrar's con-struction of.the Appendix has not altered our view (see 6 NRC at 59-60) that, as invoked in this instance, Dr. Chinnery's theory does not come within its scope.
We need not belabor the point here.
It is enough to record our belief that the
_9/
Mr. Farrar is correct on one point.
As he notes (fn.
51), our footnote 27 in ALAB-422, 6 NRC at 58, was in error in its statement that Dr. Chinnery assumed that certain 18th century Cape Ann earthquakes had had a VII level intensity.
In fact, his analysis began with earthquakes occurring after 1800.
We regret the error; it, however, did not bear materially upon our conclu-siona.
In this connection, the Board below took the 1755 Cape Ann earthquake to have been possibly as much as int 3nsity VIII (3 NRC at 919).
Although Mr. Farrar note s : hat there is "some authority for the proposition that the 1755 event was of Intensity IX", he concedes t h_a :, standing alone, that " minority view" would be insufficient to require that the Seabrook facility be bu!.lt to withstand an earthquake of that intensity.
10 NRC at (dissenting opinion, pp. 45-46).
We think tt.at concession was appropriate.
The " authority" in caestion was.a Canadian geologist named Smith, who made the first assessment of many of the New England earth-quakes.
The reason why his evaluation of the 1755 earthquake is suspect was set forth by the Board below (3 NRC at 919) ; in any event, later students of the earthquake are seemingly in agreement that it did not exceed intensity VIII.
1085 287
13 -
promulgators of Appendix A -- and its January 1977 clarify-ing amendment 1S/ -- would be very surprised to learn that an attempt was being made to predict earthquake intensities in one region based upon experience in another region without either (1) an exploration of the geology of either region in quest of similarities and differences or (2) at least some plausible explanation about why any discerned differences might be totally irrelevant.
3.
Apart from his reliance on Dr. Chinnery's analysis, Mr. Farrar asserts that (10 NRC at
, dissenting opinion, pp. 41-45) the presumed intensity IX earthquake which oc-curred near Montreal in 1732 justifies the assignment of that intensity to the Seabrook SSE.
We have nothing of sub-stance co add to the reasons we gave in ALAB-422 (6 NRC at 61-62) for declining to accept that line of argument wher.
advanced by the Coalition.
It is worthy of passing note, however, that our dissenting colleague makes no reference to tb fact, noted in ALAB-422 (ibid.), that the Montreal-Ottawa region -- unlike the New Hampshire-White Mountain region -- possesses a graben; i.e.,
a long crustal block 10/
See 6 NRC at 60.
Contrary to Mr. Farrar's suggestion (10 NRC at (dissenting opinion, p.
34), in ALAB-422 we did not treat that amendment "as though it had tightened the rules".
1085 288
, bounded by faults along its sides and depressed relative to the surrounding area.
To us, even without regard to the other dissimilarities between the two regions which were discussed in ALAB-422, the presence of an extensive fault zone in the vicinity of Montreal precludes the transferal of the Montreal earthquake to the Seabrook site for analytic purposes.
4.
We explained in ALAB-422 (6 NRC at 62-64) the foundation for our endorsement of the judgment of every ex-pert witness for the staff and applicants that it was appro-priately conservative to ascertain the ground acceleration associated with an intensity VIII earthquake by determining the mean value of the acceleration peaks of recorded seismic events of that intensity.
Mr. Farrar's rejoinder is that, whether or not it might provide a satisfactory result, that methodology is forbidden by Appendix A.
We thi.tk otherwise.
As Mr. Farrar acknowledges (10 NRC at dissenting opinion, p.
49), Appendix A must be read as requiring the plant design to take account af the maximum effective acceleration that might result from the occurrence of an earthquake of the predicted intensity.
The Appendix does not, however, appear to specify the manner in which 1085 289
. this acceleration level is to be determined.
The question thus is not whether the procedures invoked by the staff and the applicants are legally impermissible; instead, it is whether those procedures possess technical infirmities which render suspect the results obtained through their use.
We remain persuaded of the validity of our analysis of the question in ALAB-422.
This is so notwithstanding Mr. Farrar's emphasis upon what was later said by the Indian Point Board in ALAB-436, fn.
4, supra.
In that case, as here, both the staff and the licensee determined ground acceleration by calculating the average of the peak accel-erations of rei:orded earthquakes of the postulated intensity.
After giving ita. approval to that method, the Board went on to take note of tre suggestion of the licensee witness that there were other procedures which might produce more accurate correlations of intensity with earthquake damage.11/
Al-though, seizing upon that suggestion, the Board manifested its belief that the staff should endeavor to seek a more direct correlation between intensity and ground motion, it stressed that such a correlation likely would produce a result 11/
6 NRC at 585, quoted by Mr. Farrar, 10 NRC at (dissenting opinion, p. 50).
1085 290
. less conservative than that derived from the method of ascer-taining acceleration now being used by the staff.
Because Mr. Farrar does not accept this conclusion, some elabora-tion on what was said by the Indian Point majority on the point appears now warranted.
In carrying out a Fourier analysis (to which the Inciian Point majority referred (6 NRC at 585)), a complicated repeti-tive oscillation is broken down into its harmonic components.
In the instance of earthquakes, the precise nature of the associated earth oscillations (e. g., frequencies and ampli-tudes) depends upon the size of the earthquake source and the stresses involved, as well as upon the geological characteris-tics of the surrounding rock formations.
With sufficient available earthquake information for a particular region, a Fourier analysis will identify the predominant frequencies which would be produced by an earthquake in that region.
(Once those frequencies have been identified, buildings and other structures can be designed to withstand them specif-ically.)
If, then, there were considerable information available respecting the various aspects of the geologic formatious in New England which might produce an intensity VIII earchquake 1085 291 in that region, a Fourier analysis might be expected to identify the predominant frequencies associated with a New England earthquake of such intensity.
But it is clear from this record that there is very little available information along those lines.
More specifically, there has been only one New England earthquake (the 1755 Cape Ann event) which has been generally acknowledged to have been possibly of intensity VIII.
In these circumstances, in order to employ a Eourier analysis in connection with an intensity VIII earthquake, it would be necessary to look to data accumulated in the Ltudy of earthquakes in California -- the only region in the continental United States which has experienced an apprecia-ble number of seismic events of that magnitude.
But, given the indisputable and marked geological differences between the two areas, there is no reason to expect-that the predom-inant frequencies attendant upon a California earthquake of a particular intensity will correspond with those produced by a New England earthquake of the same intensity.
Thus, the use of a Fourier analysis based upon California data would give rise to a substantial possibility that the facility's seismic design -- in turn grounded upon the results of that 1085 292
. analysis -- would not be adequate to withstand the frequencies which would be actually produced were an intensity VIII earth-quake to occur in the Seabrook vicinity.
In contrast to the Tourier analysis approach, the appli-cants' and the staff's approach requires that the facility be designed to withstand *he full range of frequencies which have been encountered in intensity VIII earthquakes, no matter where in the continental United States the7 may have occurred.
Stated otherwise, instead of the plant being designed with one or two specific frequencies it mind (the ansequence of an application of a Fourier analysis), the seismic design must take into account a broad band of possible frequencies.
To be sure, this methodology does involve the averaging of the accel-eration peaks.
But to repeat what was said in AL;B-422, 6 NRC at b4, this is justified by the fact that high frequency waves (which are included in the broad band of frequencies) do not affect massive concrete structures.bS!
$/
Upon being shown this portion of our opinion, Mr. Farrar 2
informed us that it was not the Fourier analysis itself that he had in mind when he indicated in his August 3rd opinion (pp. 49-51) the approach that he favored.
- Rather, as is reflected in subsequent parts of his opinion, he believes that earthquake records should be analyzed to determine the " maximum level of damaging accelerations."
(p. 52).
As he envisioned it, this would indeed be done by evaluating the " frequency spectrum associated with" individual peak accelerations on seismograms (as the (FOOTNOTE CONTINUED ON NEXT PAGE) 1085 293
. It need be added only that none of the parties to this proceeding -- intervenors included -- criticized tre. methodol-ogy foun
%r Mr. Farrar to have been unsatisfactory, For its part, the Coalition thought an error factor should be added.
In our view, that added conservatism is unwarranted.
In sum, Mr. Farrar may be right (assuming the availabil-ity of sufficient base '.ata applicable to the region) that alternative -- and perhaps better -- means exist for corre-lating intensity and ground motion.
But it scarcely follows that the staff's and applicants' choice of the method employed by them (very likely dictated by the paucity of avail'able data on East Coast intensity VIII earthquakes) was impermissible.
To repeat, that method is not proscribed in Appendix A and the lack of precision in the results obtained from its use lies in the direction of requiring a more conservative design.
12/
(FOOTNOTE CONTINUED FROM PREVIOUS PAGE)
Indian Point Board had suggested, 6 NRC at 585, quoted in Mr. Farrar's opinion, p. 51).
But in his view, this type of analysis would be undertaken in order to obtain, not a particular frequency against which to design the plant, but the highest magnitude associated with the frequencies in the damaging range.
The magniture thus determined would se.-re as the value represer.
'.ve of the particular intensity in question; in other wor it would be corre-lated with the intensity scale in th same manner that the "mean of the peaks" currently is.
In our view, this suggestion has the same infirmity (as applied to New England earthquakes) as does the Fourier analysis.
There simply is not an adequate data base to obtain the " frequency spectrum associated with" intensity VIII earthquakes in that region.
1085 294
UNITED STATES OF AMERICA y,
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NUCLEAR REGULATORY COMMISSION
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O ATOMIC SAFETY AND LICENSING APPEAL BOARD 3%
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Michael C.
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4 Dr. John H. Buck Dr. Lawrence R. Quarles
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In the Matter of
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CONSOLIDATED EDISON COMPANY OF
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Docket Nos. 50-3 NEW YORK, INC. AND
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50-247 POWER AUTHORITY OF THE STATE OF
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50-286 NEW YORK
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(Indian Point Station, Units 1, 2
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and 3)
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September 6, 1979 Supplemental opinion of Dr. Buck and Dr. Quarles, in re-sponse to the August 3, 1979 dissenting opinion of Mr. Farrar:
At the Commission's direction,d! we conducted an extended evidentiary hearing on the seismic and geological aspects of the Indian Point nuclear reactor site located near Peekskill, New York.
On the basis of the evidence adduced at that hear-ing, we rendered a decision in which we found, inter alia, (1) that the safe shutdown earthquake (SSE) for the Indian Point site had a maximum intensity of VII; (2) that a value of 1/
1085 295 79100305 4( r
. 0.15g was appropriately assigned to the maximum vibratory ground motion (acceleration) which might result from such an earthquake; and (3) that no need existed to require the licensees to install an expanded microseismic monitoring network.
ALAB-436, 6 NRC 547, 624 (1977).
Mr. Farrar noted a partial dissent (id, at 625-29), which was recently sup-plemented by a full opinion.
In view of the fact that Mr. Farrar now is prepared to join us in the selection of an intensity VII earthquake for the Indian Point SSE (10 NRC at dissenting opinion,
- p. 7), we perceive no occasion to dwell upon the reasons he gives for doing so.
Nor is there need to discuss here the basis for his disagreement with our resolution of the ground acceleration question.
As he makes clear (pl. at dissenting opinion, pp. 47-55), his quarrel is with the methodology employed both in this proceeding and in the Seabrook proceeding for ascertaining the ground motion to which a nuclear plant is likely to be exposed as the result of the occurrence of an earthquake of a specified intensity. 2/
_2/
Mr. Farrar's dissenting opinion covers the two proceed-ings; in Seabrook, it is addressed to the views of the majority on the seismic issues there presented which were set forth in ALAB-422, 6 NRC 33, 57-64.
1085 296
. In a supplemental opinion issued today, the Seabrook Board majority responded to Mr. Farrar's criticisms of that meth-odology.
10 NRC at (slip opinion, pp. 14-16).
We agree with that response and are content to rest upon it.-3/
What that leaves is the microseismic monitoring network question which was not presented in Seabrook.
In ALAB-436, we said:
The preponderance of the evidence indicates that an expanded network will not produce data to enhance assurance of public health and safety.
The data already at hand from the existing networks do not provide any basis for requiring an additional network.
6 NRC at 624.
Mr. Farrar does not explain why this conclu-sion was wrong, other than to note the staff's belief that "something in the general vicinity appears to be ' localizing earthquake activiti'" and, therefore, " safety would be on-hanced by pursuing further investigation in the vicinity".
10 NRC at (dissenting opinion, p. 57).
In our judgment, this unparticularized (and unsupported) belief is much too thin a reed upon which to saddle the licensees and their ratepayers with the million dollar expense (see 6 NRC at
--3/
The discussion of the Fourier analysis at the conclusion of the Seabrook majority's supplemental opinion is equally applicable to a postulated intensity VII earthquake occur-ring in the vicinity of the Indian Point site.
1085 297
. 608-609) which installation and cperation of the network would entail.
This is particularly so given the general agreement (not challenged by Mr. Farrar) that the Ramapo fault -- the existence of which prompted the staff's deci-sion to call for the expanded microseismic network -- is not a capable fault.
Mr. Farrar also suggests that the network would "ad-
"anc [e ] our general knowledge of seismicity, particularly with respect to the relationship between microearthquakes and larger earthquakes".
10 NRC at (dissenting opinion,
- p. 57).
Perhaps so.
But, absent some indication (and we think there is none) that the enlarged network is neces-sary to provide r,easonable assurance that operation of the Indian Point reactors will not endanger the public health and safety, it is difficult to understand why the licensees and their ratepayers should be required to bear the consid-erable cost of broad-gauged seismic research projects.
1085 298