ML19341C224
| ML19341C224 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 02/24/1981 |
| From: | Anderson G, Bechhoefer C, Decker R Atomic Safety and Licensing Board Panel |
| To: | |
| References | |
| ISSUANCES-SC, LBP-81-7, NUDOCS 8103020422 | |
| Download: ML19341C224 (39) | |
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9 UNITED STATES OF AMERICA oocKg" I
NUCLEAR REGULATORY COMMISSION E
FEB 2 5193 > gj ATOMIC SAFETY AND LICENSING BOARD Office of the feestmy q
Docratins & Service ff Brank Before Administrative Judges:
Charles Bechhoefer, Chairman Dr. George C. Anderson sN Ralph S. Decker 4o 25 jggf In the Matter of:
)
Docket No. 50-409-SC
)
Prov. Op. Lic. DPR-45 DAIRYLAND POWER COOPERATIVE
)
)
(La Crosse Boiling Water React 0r,
)
Show-Cause Proceeding)
)
February 24, 1981
)
PARTIAL INITIAL DECISION (Permitting Continued Reactor Operation Without Site Dewaterino System)
Appearances Messrs. O. S. Hiestand and Kevin P.
Gallen, Washington, D.C.,
for Dairyland Power Cooperative, Licensee.
Ms. Anne K. Morse, La Crosse, Wisconsin, for the Coulee Region Energy Coalition,
'Intervenor.
Mr. Frederick M. Olsen, III, La Crosse, Wisconsin, Intervenor, pro se.
Mr. Stephen G. Burns and Ms. Karen D. Cyr, for the Nuclear Regulatory Comission Staff.
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, INDEX 3
I.
PROCEDURAL BACKGROUND......................
II. BURDEN OF PROOF........................
10 III.
F I ND I NGS OF F A CT.......................
13 Introduction.........................
13 14 Backgreund..........................
Events Leading to the Show-Cause Order............
15 20 Events Following the Show-Cause Order.............
Responses to Board Questions.................
24 27 Board Finding as to Liquef action...............
Risk to Public Health and Safety of Continued Operation of LACBWR without a Dewatering System Pending Final Determination
.................27 Seismic Hazard, Earthquakes of 0.12g or Higher........
31 Reconciliation of Earthquake Hazard and Standard Review Plan Criteria....................
34 Finding as to Risk of Continued Operation...........
35
- IV. ' CONCLUSI ONS OF L AW......................
36 37 V.
ORDER.....
APPENDIX, List of Exhibits.....................
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. I.
PROCEDURAL BACKGROUND On February 25, 1980, the Director, Office of Nuclear Reactor Regulation, of the Nuclear Regulatory Comission issued an Order to Show Cause under which Dairyland Power Cooperative (DPC or Licensee), the holder of Provisional Operating License No. OPR-45 for the La Crosse Boiling Water Reactor (LACBWR), was required to show cause why it should not "1.
As soon as possible, but no later than May 27, 1980, submit a detailed design proposal for a site dewatering system to preclude the occurrence of liquef action in the event of an earthquake with peak ground surface accelerations of 0.12g or less;" and 2.
As soon as possible after NRC approval of the aforesaid site dewatering system, "but no later than February 25, 1981, make such system operational, or place the LACBWR in a safe cuid shutdown condition."
The order provided an opportunity for a hearing for the Licensee or "any other person whose interest m g be affected" by the order.1I In response, the Liter see submitted a study which, it claimed, showed cause why it should not be required to design and make operational the site dewatering system. DPC sought a hearing if the NRC Staff should disagree with the conclusions reached in that study. Hearing-requEits were also 1I The order was published at 45 Fed. Reg.13850 (March 3,1980).
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_4-filed by Ms. Anne K. Morse,2_/ on behalf of the Coulee Region Energy Coalition (CREC), and by Mr. Frederick M. Olsen, III, pro,se.
By Order dated July 29, 1980, the Comission delegated to this Licensing Board the authority to' rule on the requests for a hearing and, if we determined a hearing were required, to conduct an adjudicatory hearing
" solely on contentions within the scope of the issues identified in the February 25, 1980, Order:
(1) whether the licensee should submit a detailed design proposal for a site dewatering system; and (2) whether the licensee should make operational such a dewatering system as soon as possible after NRC approval of the system, but no later than February 25, 1981, or place theLACBWRinasafecoldshutdowncondition."$/
Following this delegation, we invited the Licensee and NRC Staff to file responses to the petitions of CREC and Mr. Olsen. Memorandtsn and Order dated August 5,1980.4I We also scheduled a prehearing conference to consider the various hearing requests.E! Thereafter, in a Safety 2-The show-cause order had been issued in partial response to a request for such an order filed on May 21, 1979, by Ms. Morse.
The request had sought to suspend the LACWBR operating license for several discrete reasons. Except with respect to the liquefaction question which became the subject of the show-cause order, the request fcr license suspension was denied; with respect to liquefaction, the show-cause order permitted operation to continue for one year.
See
" Director's Decision Under 10 CFR 2.206," DD-80-9, 11 NRC 392 (February 29,1980).
SI This Order of the Comission was published at 45 Fed. Reg. 52290 (August 6, 1980).
4I We noted that no response to the Licensee-s concitional hearing request was warranted inasmuch as, if the Staff ware to continue to believe that a site dewatering system should be installed, the Licensee would have a right to a hearing under 10 CFR 2.202(c).
EI The conference was scheduled for September 11, 1980, in La Crosse, Wisconsin.
See Prehearing Conference Order dated August 22, 1980, published at 45 Fed. Reg. 57613 (August 28,1980).
. Evaluation Report (SER) dated August, 29, 1980, the Staff changed its earlier position and determined that a site dewatering system need not be installed, based upon further studies by the Licensee and review by the Staff and its consultant (WES)_, discussed infra.
At the prehearing conference we announced that we were granting the hearing requests of CREC and Mr. Olsen_/ and were consolidating the 6
two intervenors for purposes of participation in this proceeding.
We established a schedule for discovery and for the filing of motions for summary disposition. We also announced our conclusion that the size of the 4
safe shutdown earthquake (SSE) was an issue we thought should be explored in this show-cause proceeding.7/ Because the Licensee (and the Staff during the prehearing conference) disagreed with this conclusion, we agreed to certify the question of our authority to consider this issue to the Appeal Board. These rulings are memorialized in our Prehearing Conference Order Granting Requests for a Hearing and Certifying Question to Appeal Board, LBP-80-26,12 NRC 367 (September 30,1980).8_/
On 0! Previously, Mr. Olsen had moved to disqualify the entire membership of this Licensing Board. We denied this motion in our Memorandun and Order dated September 19, 1980.
In accordance with 10 CFR % 2.704(c),
we referred this denial to the Appeal Board. On September 24, 1980, the Appeal Board summarily affirmed our ruling. ALAB-614,12 NRC 347.
7,/
In its full-term operating license application, dated October 9, 1974, DPC proposed 0.12g as the peak ground acceleration.resulting from the SSE. Show-cause order, p. 2, 45 Fed. Reg.13850. The Staff has not yet completed its evaluation of this proposal.
In LBP-80-26, we descr%ed why we believed that we should determine the acceptability of this proposal rather than assuming its validity for the purposes of this praceeding.
0-Before the Appeal Board, the Staff changed its earlier tentative position and agreed we were empowered to consider, and should consider, the magnitude of the SSE. The Appeal Board affirmed our earlier ruling.
ALAB-618, 12 NRC (November 17,1980). On December 1, 1980, the Licensee sought Comission review of the; e rulings. The 'Comision has not yet acted on that request.
. we issued a Notice of Hearing.EI September 30, 1980, In our Memorandum and Order Scheduling Evidentiary Hearing and Prehear-ing Conference, dated November 12, 1980, we stated that, were we to find that the installation of a dewatering system as proposed by the show-cause order was required, the Licensee could not design such a system, have it 25, 1981, the cut-of f approved by the NRC Staff, and install it by February We also expressed some reservation date specified in the show cause-order.
whether we would be able to render an initial decision prior to February 25, 1981.b We further observed that the on., year period of operation which the show-cause order permitted had been based on a hazard analysis performed by the Staff and that any further extension of time (absent a final decision in this proceeding) would require an additional hazard We therefore scheduled an evidentiary hearing on the risks of analysis.
continued operation pendente lite (including 5 particular areas of inquiry whichweidentified).E On November 14, 1980, the Licensee and NRC Staff each filed motions for sununary disposition, covering all issues except the Board-raised question of EI This Notice was published at 45 Fed. Reg. 66537 (October 7, 1980).
Among other matters, we noted that we had some substantive ques-tiens which we intended to pose to the parties in the near future and that we expected to have answers to those questions prior to any final determination in this proceeding.
E We also scheduled a prehearing conference to consider any sununary disposition motions which might be filed, the manner in which the parties proposed to respond to Board questions (see fn.10, supra), and further scheduling. A Notice of Prehearing Conference and Evidentiary Hearing was publ1shed at 45 Fed. Reg. 76557 (November 19,1980). The schedule for the prehearing conference and evidentiary hearing was slightly mod fied by our Order of November 25, 1980, published at 45 Fed. Reg. 79954 (December 2,1980).
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' the size of the SSE. The Intervenors fai'ad te respond to either motion.
(The Staff on December 9,1980 supported the Licensee's motion except with respect to one limited question relating to the soils beneath the stack of the adjoining Genoa-3 coal fired plant. The Staff had not reviewed these studies but deemed them extraneous to our eventual determination.)
On December 5,1980, we issued a Memorandum which posed the substantive questior, to which we sought answers prior to any final determination in this proceeding (see fn. 10, suora). We noted that at the forthcoming pre-hearing conference,
would discuss the manner in which these questions would be addressed; as it turned out, the Licensee and NRC Staff were able to respond to the questions adequately at the evidentiary hearing.
On December 16 and 17,1980, we conducted an evidentiary hearing on the risk of extending the February 25, 1981 cut-off date. Testimony was pre-sented by the Licensee and the NRC Staff.
The witnesses for those parties also' offered to address the substantive questions raised by the Board in the Memorandum of December 5,1980, as well as certain leestions arising from the affidavits provided in support of the Licensee's and Staff's motions for suninary disposition.
As a result of the Intervenors' f ailure to respond to those motions, and because the questions also were pertinent to the direct case presented by the Licensee and Staff concerning the risk (or lack of risk) of extending the cut-off date, we found no due-process objection to the witnesses' addressing those matters without having submitted prepared testimony on the particular questions..During the course of the hearing, the witnesses responded to our cuestions.
Because the Staff had earlier indicated that it w:Jld not be prepared to address the SSE question for at least 6 mcnths, we limited the inquiry at the December hearina to the risk
. of liquef action arising from the Licensee's and Staff's assumed SSE, pro-ducing peak ground acceleration of 0.129 at the site.
Determination of the SSE, and additional liquefaction potential which might attend an SSE pro-ducing greater than 0.129 ground acceleration at the site, was accordingly deferred to a later date.
At the prehearing conference following the evidentiary hearing on December 17, 1980, we established a schedule for the submission of proposed findings 'of fact and conclusions of iaw (as well as for discovery on the remaining SSE question).
See Prehearing Conference Memorandom dated January 6,1981. Proposed findings and conclusions were submitted by the
!.icensee and Staff. The Intervenors did not do so.
(The Licensee also responded to the Staff's proposed findings and conclusions, offering no objection to them.)
In preparing the following findings of fact and conclusions of law, we have reviewed and considered the entire record of thir proceeding, including the affidavits submitted in support of the motions for summary disposition and the findings of f act and conclusie e of law proposed by the parties.
Those proposed findings not incorporated directly or inferentially in this Partial Initial Decision are rejected as being unsupported by the record or as being unnecessary to the rendering of this Decision.
We have also con-sidered the limited-appearance statements from members of the public received during the evidentiary hearing sessions.
For the reasons which follow, we find no warrant for the installation of a dewatering systeh, to preclude liquefaction in the event of an earth-quake producing peak ground acceleration -at the site of 0.12.
We also 9
reiterate our conclusion of the necessity of definitively ascertaining the
9 size of the SSE for this facility prior to any final determination of the l
need for a site dewaterirg system. Finall-y, we conclude that there is no
. undue risk to the, public health and safety in permitting operation pendente lite, without installation of a site dewatering system.
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, II. BURDEN OF PROOF At the outset of the evidentiary hearing (Tr. 73-77), the Licensee took the position that the burden of proof (as well as of goiy forward with evidence) sWid be placed on the Intervenors.
DPC reasoned that, because of the S'.ff's change in position, the Intervenors were the only rcmaining parties seeking imposition of the remedies sought by the show-cause order; and, for that reason, became the " proponents" of the order within the meaning of 10 CFR 52.732 and Section 7 of the Administrative Procedure Act, 5 U.S.C.
556(d). We ruled that DPC had the t,urden of proof (Tr. 77).
This ruling was premised upon our understanding of the decisions of the Appeal Board in Consumers Power Co. (Midland Plant, Units 1 and 2),
ALAB-283, 2 NRC 11 (1975), clarified on reconsideration, ALAB-315, 3 NRC 101 (1976). There, in a show-cause proceeding arising after the grant of a i
construction permit but prior to the award of an operating license, the Appeal Board held that the Atomic Energy Act modified the normal rule of the Administrative Procedure.Act by placing the burden of proof on safety matters on -the construction permit holder (the licensee). We interpret f
these decisions as according the burden of proof to the licensee, at least until award of a full-term operating license. The intercession of a provisional operating license does not alter this statutory scheme. As the Appeal Board pointed out, a utility must bear the " burden of proving compliance with Comission safety regulations" at the beginning and end of the licensing process, as well as in the interim (ALAB-315, 3 NRC at 104);
since a provisional operating license has only limited life and a holder of l
i
4 such a license still must prove its entitlement to a full-term license, the licensing process has not yet ended for the holder of a pro.isional licenst.
As a result:
- *
- the Atomic Energy Act intends the party seeking to
- *
- operate a nuclear reactor to bear the burden of proof in any Coninission proceeding bearing on its appli-cation to do so, including a "show cause" proceeding.
Id_. at 105.N The subject matter of this show-cause proceeding clearly bears upon DPC's application for a full-term operating license. This issue could readily be litigated in that context, and DPC would have the burden of proof.
The circumstance that the liquef action issue was hrought to light prior to the completion of the Staff's review in the operating license proceeding should not, and in our opinion does not, shift the burden of proof from the Licensee. E. ALAB-283, supra, 2 NRC at 17.
DPC asserted 'two reasons why, in its opinion, the Midland decisions do not govern the instant show-cause proceeding'.
First, it claimed that the decisions do not address the situation, as here, where the Staff is no longer advocating the criginal position taken in the show-cause order (Tr.
74). Midland, however, involved an analogous situation:
during the hearing, the show-cause order did not enjoy the support of any active party,,
N The Appeal Board expressly reserved judgment with respect to the burden of proof in a show-cause proceeding involving potential withdrawal of an operating license.
ALAB-315, 3 NRC at 109, n. 20.
Our decision here, of course, involves only a provisional and not a full-term operating 1,icense.
4
. since the intervenors were no longer participating and the Staff no longer f avored the order. ALAB-283, supra, 2 NRC at 15.
Second, DPC. argued that the Midland burden-of-proof interpretation is about to be modified by the Connission.
It referred to the NRC's 42 Fed.
publication of a proposed rule which would lead to that result.
Reg. 37406 (July 21, 1977). We understand, however, that the Commission is about to withdraw the proposed rule and accordingly allow the Midland ruling to remain in effect. The Staff confirmed this understanding (Tr. 75-76).
In any event, we are bound by Midland (to the extent applicable here) unless and until it is modified or abrogated by the Commission.
In sum, we hold that the burden of proof in this proceeding falls on
.DPC.12/ And although under Midland the Intervenors may have the burden of initially demonstrating evidence sufficient to cause us to inquire further ( ALAB-315, 3 NRC at 112), their reliance on a 1978 study of the U.S.
Army Engineer Waterways Experiment Station (see pp.15,19, infra) amply satisfies ' U11s requirement.
l 12/ The circumstance whereby we permitted the Staff to present a portion of its testimony prior to the Licensee's testimony resulted from schedule conflicts of one Staff witness and does not in any way stem from the allocation of the burden of proof 'or burden of going
. forward.
9
. III. FINDINGS OF FACT Introduction The Licensee's direct testimony was sponsored by a witness 1.
panel consisting of Dr. Robin K. McGuire, a Senior Engineer with Dames
& Moore specializing in risk analysis, earthquake engineering, and decision analysis; Dr. Mysore S. Nataraja, a Senior Engineer at Dames &
Moore specializing in soil mechanics, earthquake engineering, and geotechnical instrumentation; and Mr. John D. Parkyn, the Assistant Superintendent of LACBWR. This testimony ("DPC panel testimony") was admitted into evidence at Tr. 306.El Messrs. Nataraja and Parkyn also sponsored affidavits in support of the Licensee's motion for summary disposition.
(References to those affidavits will appear as "Nataraja aff." or "Parkyn aff.".)
The Licensee also presented testimony by Mr. Richard Shimshak, LACBWR Superintendent (Tr. 384-85).
The Staff presented testimony by Dr. Leon Reiter, Leader of the Seis-mology Section in the Geosciences Branch, Division of Engineering, Office of Nuclear Reactor Regulation, NRC (Reiter testimony, fol. Tr.
- 85) and by Mr. Howard A. Levin, Technical Assistant to the Director, Division of Engineering (Levin testimony, fol. Tr. 90). The Staff's motion for summary disposition was supported by the aff ; davit of Mr. John T. Greeves, a Geotechnical Engineer in the Hydrologic and Geotechnical Engineering Branch of the Division of Engineering EI All transcript references are to the transcript of tne evidentiary hearings held on December 16 and 17,1980.
. ("Greeves aff."). Mr. Greeves appeared as a witness but did not sponsor direct testimony (except to the extent that he had participated inpreparationoftheStaff'sSER).b His professional qualifi-cations were adinitted into evidence and appear fol. Tr. 92.
A list of exhibits appears in the Appendix to this decision (infra, p. 39).
Background
2.
The La Crosse Boiling Water Reactor (LACBWR) is located on the east bank of the Mississippi River near Genoa, Wisconsin. SER, p. 1.
It is currently permitted to operate under Provisional Operating License DPR-45.
OPC has applied for a full-term operating license; that application is currently under review by the Comission. The
. review of safety issues for LACBWR has been performed in the context of the Comission's Systematic Evaluation Program (SEP), a program under which NRC is reevaluating the safety margins of a number of older reactors, including LACBWR. During the course of that review, the question of liquef action potential at the La Crosse site surfaced, leading to issuance of the Februsry 25, 1980 show-cause order.
3.
Soil at the site consists primarily of sand deposits and emplaced hydraulic fill material extending to a depth of approximately 130 feet, down to bedrock.
SER, p. 1; DPC panel testimony, p. 3.
The reactor containment building, e turbine building and the stack are all pile supported structures. The crib house and associated underground piping which are also important to safety are not pile supported. DPC panel testimony, p. 6; Parkyn off., para. 2.
I "SER" refers to We " Safety Evaluation by the Office of Nuclear Reactor Regulation Relating to Liquefaction Potential at the La Crosse Site," dated August 29, 1980, identified as Staff
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Exhibit 5 and admitted into evidence at Tr. 96.
. 4.
Loose to medium sands of the type found at LACBWR tend to compact when subjected to cyclic loadinos such as those induced by an earthquake.
If the sand is saturated, sufficiently strong vibratory motion can cause ' reduction in its shear strength so that the sand is unable to resist the imposed shear stresses. Under these circum-stances, the sand can behave much like a liquid, i.e., liquef action can occur.
SER, p. 2; DPC panel testimony, p. 3.
Generally, the stronger the earth. shaking, the longer it lasts; and the wetter and less dense the sand, the more likely it is that liquefaction will occur.
Events Leading to the Show-Cause Order 5.
To assist in evaluating the liquefaction potential at LAC 8WR, Dairyland engaged the services of Dames & Moore, an engineering con-sulting firm whir' took soil samples on several occasions, performed liquef action analyses, reported its findings, and advised the Licensee.
Similarly, the NRC Staff called upon the Geotechnical Laboratory, U.S.
Army Engineer Waterways Experiment Station (WES), to analyze available
.information, prepare a report, Liquef action Analysis for LaCross [ sic]
Nuclear Power Station, December,1978 (hereinafter WES Rpt.), and provide advice to the Staff. As shall be s6en, the analysis and conclusions of the WES' Rpt. provided a foundation for the Staff's issuance of the 1980 show-cause order.
6.
Two methods, comonly referred to as the analysis / testing methodb and the empirical method, were used by both Dames &
Moore and WES to evaluate the liquef action potential at LAC 8WR. DPC E This method is also referred to as the laboratory / analytical approach.
, panel testimony, pp. 3-4; SER, p. 2.
The analysis / testing method consists of taking soil samples at the site in question, modeling the site soil condition in the laboratory, conducting a series of cyclic, tri-axial tests on the samples, establishing the cyclic shear strength for the soil over a range of confining pressures, and comparing shear strength with dynamic shear stresses.
DPC panel testimony, p.
4; SER,
- p. 2.
The empirical method utilizes Standard Penetration Tests (SPT),
in which a rod of standard shape is driven into the soil by standard impacts and the number of blows required to drive the rod through a unit depth is counted. These data are then compared with the blow counts measured at many other sites where, soil performance under actual earthquake conditions has been recorded.
Id. The more blows required to drive the rod a unit depth, the denser is the soil and the more the soil is able to resist liquef action.
Both methods require a specification of expected vibratory ground motion and a knowledge of soil properties.
7.
In describing earthquake induced vibratory ground motion at the LACBWR site, the Staff, the Licensee, and their consultants have all used peak ground surface acceleration as the principal parameter.
Other descriptive parameters such as magnitude, intensity and duration of ground shaking can be rela +.ed to peak acceleration.
For example, the show-cause order states (at pp. 4, 6, 45 Fed. Reg. at 13850, 13851):
- *
- that if sustained strong ground motion with peak accelerations of.12g or higher occurs (normally associated with a magnitude 5 or greater earthquake within 10 km of the site) ' * *'
, and This peak acceleration (.129) is equivalent to Intensity VII when using the relationship of Trifunac and Brady (1975).
Moreover, the duration of ground shaking, which is of ten expressed in terms of uniform cycles for soil testing and analysis purposes, is also related to peak acceleration, earthquake magnitude and intensity.
In this case, the Staff states in its SER (at pp. 2-3):E
'There has been general agreement between the staff and the licensee that the earthquake loading at the La Crosse site-can be conservatively characterized as a magnitude 5 to 51/2 event at a distance of less than 25 KM with a peak ground acceleration of 0.12g* and an equivalent duration of 5 cycles.
- g is acceleration of gravity, i.e. 32.2 ft/sec/sec" 8.
In this phase of the show-cause proceeding, peak ground surface acceleration is assumed to be 0.12g as specified in the show-causeorder.N As indicated earlier, however, the Board See also WES Rpt., Figures 9 and 10; Tr.184-185.
N 'By way of background, it is interesting to note that WES used a more severe specification of ground motion in its liquefaction anal-ysis appearing in its 1978 report. For that study, Staff specified peak accelerations of 0.12g and 0.20.
9 However, WES assumed an Intensity IX or magnitude 6.6 earthquake
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with a duration of 10 cycles. WES Rpt., para. 17, pp. 8-9.
In assessing the WES analysis, the Staff concluded, smong other seismicity at the site were things, that the ass (aptions regarding(45 Fed. Reg. at 13850).
conservative.
Show-cause order, p. 2 se---
t
. believes that a substantial question exists concerning the adequacy of this assumption and that this question must be resolved prior to a final determinat. ion in this proceeding of whether a dewatering system need be installed to preclude liquef action at the LACBWR site.
See LBP-80-26, supra,12 NRC at 376-379; also p. S of this Decision.
9.
The initial soils investigation at the La Crosse site was conducted in 1962 by Raymond International. Additional borings were made in 1973 under Dames & Moore supervision. SER para. 2.0 and Fig. 1.
These data were included in DPC's 1974 full-term operating license aplication and were utilized by WES in its liquefaction analysis.1E/ The NRC Staff's assessment of the WES analysis
$E/ o understand the evolution of knowledge of soil properties at TLACBWR and the results of the several liquef action analyses performed, it is again instructive to recognize the limited information available to WES in the conduct of its 1978 evaluation.
WES reviewed the data from the 1962 and 1973 borings but was unsure whether penetration tests were conducted by standardized methods.
WES Rpt., para. 7.
WES also noted that some soil samples were taken using one technique and others by a different one. WES Rpt.
para. 8.
WES was aware that the turbine and reactor containment buildings and the stack were pile supported. However, it was uncertain as to whether some of the borings were made prior to or following pile driving. WES Rpt. para. 8.
WES estimated the increase in soil density under pile supported buildings based solely on the reduction in void ratio which would occur assuming the soil displaced by the pile went entirely into taking up the voids of the adjacent soil. The increase in soil density so estimated was minor and WES did not consider it to be significant.
WES recognized that additional density could have occurred due to vibration during pile driving but data were not then available to support this hypothesis. WES Rpt., para.11.
e
. indicated that the then-available soils data were inadequate to estimate accurately the liquefaction resistance.
See show-cause order,
- p. 3 (45 Fed. Reg. at 13850). Consequently the Licensee undertook an additional soils investigation program which was reviewed in advance and approved by the Staff in April,1979. Based on analyses of the data obtained in the five additional borings made in the LACBWR yard area in May,1979, Dames & Moore concluded that, for the postulated earthquake with a 0.12g peak ground acceleration, the laboratory /
analytical approach yielded a minimum safety factorEI of 1.5 and the empirical approach a minimun value of 1.0.
However, after review by WES and itself, the Staff concluded that the laboratory shear strength curves used in the Dames & Moore analysis were not adequately conservative and that foundation soils down to a depth of approximately 40 feet were not safe against liquef action if subjected to sustained ground motion with a peak acceleration of 0.12g or higher (which the Staff associated with a magnitude 5 or great'er earthquake within 10 km.
of the site). Because of this Staff conclusion, the Licensee proposed a plan for dewatering the site to lower the groundwater level.
However, Dairyland subsequently withdrew the proposal. As a result, the show-cause order was issued by NRC on February 25, 1980. SER, l
para. 3.0; show-cause order, p. 4 (45 Fed. Reg. at 13850).
EI WES states that "[t]he factor of safety against 10 percent double-amplitude strain has been defined as the dynamic shear strength divided by the average dynamic shear stress." WES Rpt.
para. 19. The higher the safety factor, the more resistance there is to liquefaction.
4
, Events Following the Show-Cause Order 10.
In response to the Order to Show Cause, Dairyland cited the improved density which could be expected due to vibration durina the driving of piles,' surveyed pertinent case histories, and subsequently made four additional test borings (which were monitored by Mr. Greeves of the Staff, Tr. 110). These borings were made through the turbine building floor and stack foundation into soils directly below these structures, in contrast with previous borings made in the yard area or free field. These borings clearly indicated significantly greater soil densities under the pile-supported structures than in the free field.
Analysis and evaluation of these results were reported by Dames & Moore i,n July, 1980.
Upon review of the logs of these new borings and the data reported by Dames & Moore and the Licensee, the Staff and WES concluded that the soils below the reactor containment building, the turbine building and the stack are adequetely safe against El liquefaction effects for an earthquake up to'a magnitude 5.5 with a peak acceleration of 0.12g.EI The Staff also concluded that mitigative measures (e_.3., the dewatering system) to increase the margin of safety against liquefaction for these structures are not EI In response to questioning by the Intervenor, Staff witness Greeves stated that liquef action has not been experienced and recorded for earthquakes of magnitudes less than 5.5.
Tr. 113.
Dr. McGuire, in response to a Board inquiry, stated that the magnitude of the smallest earthquake of which he was aware which did cause liquef action was approximately 5.3.
Tr. 374.
El Corps of Engineers, Letter from F. R. Brown to J. P. Knight (NRC), July 25, 1980, Ref. 5 to SER.
21 -
needed. However, liquef action remains a concern for the crib house and associated underground piping, which provide one of the sources of emergency core cooling water to the reactor containment building and which are not pile supported.
SER, para. 3.0; DPC panel testimony,
- p. 6.
Therefore, the Licensee is installing a redundant dedicated safe shutdown system to be housed inside the turbine building to provide additional emergency cooling water and preclude reliance on the crib house and buried piping in the event of an earthquake. Licensee is required by Staff to have this system operational by February 25, 1981.
DPC panel testimony, p. 6; SER, para. 3.0; Tr. 312, 356, 377.
- 11. As we have described earlier (supra, pp. 6-7), both the
" Licensee and the Staff, having reached agreement that a dewatering system is unnecessary, entered motions for sunnary disposition, to which the Intervenors did not respond. As part of its motion, through the Greeves affidavit, the Staff responded to certain concerns expressed by the Intervenors during discovery, as well as at the 1
September, 1980 prehearing conferer.ce.
- 12. For example, the Intervenors disagreed with the Staff's posi-tion as expressed in the SER that borings under the turbine building and stack foundation are representative of adjacent pile supported i
structures.
In his affidavit, Mr. Greeves responded that borings th' rough the turbine building floor were carefully selected to represent l
the lower end of the range of soil density for pile supported struc-l tures and that turbine building piles are more widely spaced relative l
l to the piles under the stack and reactor building. Moreover, soil density generally increases with distance from the river bank and e
w r
,,-v g
, borings under the turbine building were closer to the river than those under the stack foundation. The reactor building is locatec' still further from the. river. Mr. Greeves therefore concluded that borings under the turbine building are in fact a conservative representation of soil conditions under other pile-supported foundations on the LACBWR site and that borings under the stack foundation are a conservative representation of conditions under the reactor. Greeves affidavit, pp. 3-5.
- 13. The Intervenors also noted that piles are not supported by bedrock. Mr. Greeves responded that the Staff does not rely on the support of the piles themselves to resist liquefaction but on the
" ncreased soil density resulting from the driving and presence of the i
piles. Greeves affidavit, pp. 2-3; Tr. 286.
- 14. The Intervenors observed that shallow voids were found under the turbine building during borings and raised the concern that voids l
might also exist under the reactor building. Mr. Greeves responded that the soil under the turbine building and stack are hydraulic fill and that voids were not found under the stack at the same elevation.EI Moreover, pile spacing is closer under the reactor building than under the turbine building. Greeves affidavit, pp. 4-5; l
Tr. 377-382.- Under' direct examination, Mr. Richard Shimshak, LACBWR i
l Superintendent, also testified that voids might well be expected under the turbine building due to turbine vibrations, a condition not present E
The reactor building does not rest on hydraulic fill. Rather its base is 29 feet below grade and rests on the denser soil existing there before the surface grade was raised with fill material.
SER para. 2.0; Dames & Moore " Response to NRC Review Questions" transmitted by letter of July 14, 1980 from Frank Linder, DPC to Dennis Crutchfield, NRC, p. II-13; Tr. 365.
l I
- es under the reactor building or under the stack.
Tr. 384-385.
In any case, Dames & Moore witness Nataraja testified that the presence or absence of voids has no bearing on his conclusion regarding liquefaction.
Tr. 382. The voids under the turbine building have nevertheless been filled.
DPC panel testimony, p. 6; Tr. 378; Parkyn affidavit, p. 2.
- 15. The Intervenors noted that the driving of piles could also increase pore pressure, a condition which accompanies liquefaction.
The Staff agreed but pointed out that any increased pore pressure dissipates shortly after the pile is driven and nas no further significance.
Greeves affidavit, p. 5.
16.
Mr. Greeves also addressed the question of whether dense soils such as those beneath pile supported structures would remain stable even if adjacent soils in free field areas undergo liquef action.
He expressed his view that denser soils would remain stable and stated that this had been demonstrated in response to actual events.
In particular, he cited and attached a study which reported that pile supported oil tanks at Ishinomaki, Japan, remained stable even though surrounding soils liquefied extensively as a result of the Miyagiken-oki earthquake of June 12, 1978.
During questioning by the Board, Mr. Greeves testified that the situation at LACBWR and the oil tanks at Ishinomaki were comparable.23/ He also pointed out 23/
In response to questions by the Intervenors, Mr. Greeves acknowledged that the piles under the oil tanks and those under the LACBWR structures were different in nature. Tr. 274-275.
But he testified that the degree of densification produced in each case is the significant factor and that the densification at Ishinomaki and LACBWR was comparable--indeed, the LACBWR soils reflected slightly higher densification. Tr. 281, 285.
that the oil tank site was subjected to a magnitude 7.4 earthquake with ground scrf ace accelerations around 0.18g up to 0.25q and a duration of 20 equivalent cycles. Mr. Greeves opined that such a magnitude involves effectively 100 times }/ the energy of a magnitude 5.5 2
earthquake. Tr. 271.
Responses to Board Questions
- 17. After the summary disposition notions had been filed, the Board evaluated the total record to date, including the affidavits supporting the motions. Because we believed the record to be still somewhat incomplete in a few areas, we posed several questions which were provided to the parties by our Memorandum of December 5,1980.
As described earlier (supra, p. 7), these questions were responded to by Licensee and Staff witnesses during the evidentiary hearings on December 16 and 17,1980. A summary of the questions and responses follows.
- 18. Our first question related to the effects of Mississippi River water level on the below grade water table, and the consequent effects on soil properties (and thus on liquef action potential).
Witnesses for both the Staff and Licensee agreed that a rise in Mississippi River water level would be accompanied by a rise in the water table, that soils below the higher water table would become saturated, that resistance to liquef action would be reduced, but that even at flood stage where the water table rose to the surface, soils under pile supported structures are sufficiently dense to resist liquef action should an earthquake producing a peak acceleration of 25/ On the basis of its own estimates, the Board believes that this figure is low.
' 1 0.12g occur. Tr. 248-252, 391-392.
The Licensee testified that the probability that a flood and an SSE producing 0.12g ground acceleration would occur simultaneously is very low. Tr. 389-390, 392.
- 19. We then asked if there would be a density gradient radially outward from each piling, where samples were taken radially from pilings, and whether the gradient was considered in the liquef action analyses. Again, both Staff and Dairyland witnesses testified that some density gradient would be expected laterally from a single ciling and also laterally from a group of pilings into the surrounding free field.
Such density gradients would be expected to persist with time.
Moreover, in order to avoid striking pilings during borings for samples under the turbine building, the boring was made as close to the midpoint between pilings as possible so that the samples obtained should be of lower density than had they been obtained inmediately adjacent to a piling. Tr. 120-124, 361-364. The differences would not be significant. Tr. 364.
- 20. We also asked if a dewatering system designed to protect against liquefaction at 0.12g would be effective at 0.20g as well.
Dames & Moore witness Nataraja testified that the preliminary dewt.tering system design _ so far considered would not preclude licuefaction at 0.20g unless the factors of safety were already sufficiently large. Larger diameter wells, longer screens or higher capacity pumps would likely be required to lower the water table still further. Dr. Nataraja also pointed to certain detrimental effects of dewatering systems and indicated that they would be greater if a higher capacity system were installed. Tr.
393-396.
. 21.
Since the show-cause order was not explicit as to the duration of ground shaking, we asked for clarification.
Dr. Nataraja testified that liquef action potential did depend on the duration of ground shaking as well as magnitude and accleration, that these parameters were related, that Dames & Moore had used five equivalent uniform cycles, and that that number was conservative.
He referred to Figure 10 of the WES report which is a plot of equivalent number of cycles vs.
earthquake magnitude and indicates the degree of conservatism associated with the selection of five cycles for purpose of 'iquefaction analysis. Tr. 396-399.
22.
In his affidavit supporting Licensee's motion for sumary disi ssition (para. 9,10), Dr. Nataraja stated that the factor of safety against liquef action is " greater than the normally accepted minimurn f actor of safety." However, he did not elucidate on the term "normally accepted minimum factor of safety." We asked for clarification.
Dr. Nataraja testified that the f actors of safety determined by Dames' & Moore were higher than 1.25, that there is no minimum f actor of safety for~ all cases but that, in his opinion, the f actors of safety obtained are adequate by all standards. Tr.
371-374.2_6/ Staff wit' ness Greeves agreed that a safety factor of 1.25 would be a reasonable guide if it were properly derived considering investigation and analytical techniques and experience level. Tr. 256-257.
20 The WES Rpt. states (para. 20) that a' factor of safety of 1.25 "is often considered reasonable' for safety in the type of analysis performed herein."
. Board Finding as to Liquefaction
- 23. Upon careful consideration of all the evidence summarized above, the Board finds that there is reasonable assurance that soils under pile suppor'ted structures will not liquefy if subjected to a 5.0 to 5.5 magnitude earthquake with peak ground acceleration of 0.12g or less. There is al'so reasonable assurance that additional emergency cooling water can be provided for safe reactor shutdown using a dedicated. safe shutdown system which is required to be installed by February 25, 1981.
We therefore find that the installation of a dewatering system is not required to protect against liquefaction in the event of the foregoing earthquake.
Risk to Public Health and Safety of Continued Operation of LACBWR without a Dewatering System Pending Final Determination
- 24. When we scheduled the December 16-17, 1980 evidentiary hearings, we were concerned that we might not be able to reach and publish a decisi sefore the February 25, 1981 deadline specified in the show-cause order on the limited question of whether a dewatering system would be needed to protect against liquefaction resulting from a 0.12g earthquake. Moreover, should we have found a dewatering system l
necessary, installation could not possibly have been completed by the cut-offdate.SE! Further, we estimated that approximately another year would be required to complete litigation of the broader question l
S2! Dairyland estimates that it would take approximately six months to design and install a dewatering system.
DPC panel testimony, footnote 3, p. 9.
Staff estimates a period of two months to review a proposed dewatering system design.
Levin i
l
-testimony,.at p. 4.
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, of what the safe shutdown earthquake (SSE) should be and whether a dewatering system would be required should that %E result in peak Conse-ground surf ace accelerations greater than 0.12g at the site.
quently, we ordered evidentiary hearings on the risk involved in con-c al tinuing operation without a dewatering system and identified areas of inquiry to be addressed with respect thereto.
- 25. Both the Licensee and Staff took the position that soils under pile supported structures important to safety would remain stable and not liquefy if subjected to an earthquake resulting in earth shaking with a peak ground surface acceleration of 0.129 Therefore, both concluded that continued operation of LACBWP, without a dewatering I
system would pose no risk to public health and safety even if the site l
were subjected to an earthquake producing ground acceleration of up to 0.12g.
- 26. For the reaans summarized in paragraph 23 of these findings, we agree with this risk analysis. Nonetheless, as we ruled in LBP-80-26 (see p. 5, supra), determination of an SSE and the lique-f action potential of that SSE are both necessary in order to reach an informed decision on the necessity for a site dewatering system. We have not yet been able to complete our consideration of this matter--
discovery is still in progress, the Staff has not yet furnished its i
analysis of this question, and hearings have not yet been held.
If we should later determine that the SSE is above the liquefaction threshold, operation without a dewatering system pendente lite would involve some seismic risk.
, 27. When it issued its show-cause order, the NRC Staff concluded that the return period for an earthquake producing a peak ground acceleration af 0.129 would be at least 1,000 years--i.e_., the proba-bility of occurrence of such an earthquake would be 10-3 or less.
(The Staff noted that, while this value should not be interpreted as an absolute minimum, the actual return period could be an order of magni-tude larger.) As a result, the Staff concluded "that the general level of seismic hazard at the LACBWR site is sufficiently low that operation of the plant for the next twelve months would not endanger the health and safety of the public." Show-cause order, pp. 6-7; 45 Fed. Reg. at 13851. The Connission itself declined to review this decision of the Staff (as well as other portions of the Diretor's Decision (00-80-9) which declined to adopt further relief, including ininediate license suspension, requested by Ms. Morse). See Memorandum dated April 17, 1980 from Samuel J. Chilk, Secretary, to Leonard Bickwit, Jr., General Counsel, subject: SECY-A-80-43 (enclosure 3' to NRC Staff's Response to Requests for Hearing, dated August 29,1980).
28.
In undertaking the foregoing analysis, the Staff was assuming that liquef action could occur in the event of an earthquake producing O.12g ground acceleration at the site. Although we have found that assumption not to be valid, we find that, prior' to our resolving the SSE question, we must evaluate the risk, if any, of continued operation pendente lite,.and that the risk criteria utilized by the Staff in the show-cause order are appropriate guidelines for us to use in evaluating the risk of liquef action in the event of an earthquake producing greater than 0.12g ground acceleration.
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- 29. The seismic hazard giving rise to such risk is an earthquake producing ground acceleration at or near the site of greater than 0.12g.
In response to our specific questions, Licensee and Staff both presented estimates, discussed T.;e fully below, of the " seismic hazard," i.e., the annual probability of occurrence (or its reciprocal, the return period) of a 0.12g or greater earthquake. We note here that, as Staff testified, " seismic hazard" is only one element of
" seismic ' risk." To estimate seismic risk involves combining the probability of occurrence of the causal event with the probability that harmful effects to public health and safety will eventuate.
Neither Staff nor Licensee had undertaken a quantitative seismic risk analysis over 'a range of peak ground surface accelerations over 0.129.23/
Factors which would have to be considered in such a seismic risk analysis include the extent to which pilings would continue to support buildings even if underlying soils liquefied, means and probabilities of successful core cooling, breach of primary coolant boundary
~
probabilities, extent and probability of containment, type and degree of release of radioactive material, probabilities of a range of
. meteorological conditions prevailing at the time of release, population locations, densities, and probability of successful evacuation or other protective measures. Tr. 223, 406-409.
2E/ Staff witness Levin testified tnat quantification of these factors for La Crosse is not planned and is beyond the state-of-design at this time. However, the NRC Office of Research is currently conducting a srobabilistically based generic program called the Seismic Safets Maroins Research Program which is attempting for the first time to quantify seismic ~ margins rigorously. Levin testimony, pp. 3-4; Tr. 405.
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. ~ ismic Hazard, Earthquakes of 0.12g or Higher e
- 30. Both the NRC Staff and the Licensee presented estimates of
" seismic hazard"--i.e., the annual probability of occurrence of an earthquake resulting in ground acceleration at LACBWR of 0.129 or greater (or its reciprocal, the return period).
- 31. The Staff's estimates stemed from a review of results thus far available from the Site Specific Spectra Program (SSSP), an effort conducted for the Staff by the Lawrence Livermore Laboratory and the TERA Corpora' ion.
In the SSSP, return periods were calculated for peak ground accelerations, peak velocities and response spectra at eastern and central U.S. sites including the LACBWR site.
Since there is
' insufficient historical earthquake experience in the central U.S. to conduct seismic hazard analyses solely on empirical data, judgment must be used in the selection and limitations of certain parameters and empirically derived relationships.
In the LLL-TERA studies, experts on eastern seismicity were polled wit: respect to seismic zonation, frequency of earthquake occurrences, upper magnitude cutoff, aad characterization and attenuation of ground motion.
Specific earthquakes such as those at Anna, Ohio, and New Madrid, Missouri, were taken into account.b The attenuation model used in the return b The July,1980 Maysville, Kentucky earthquake occurred after polling of the experts ar.d coul.d not therefore have been taken into account.
However, based apon an examination of individual experts' assumed zone configurations and the size and frequency of earthquake distributions, it appears that inclusion of this earthquake into considerations would have minimal, if any, effect.
Reiter testimony, pp. 3-4 The magnitude of the Maysville earthquake was in the range of 5.0 to 5.5, which -is the value being considered by the Staff for LACBWR.
Tr. 131.
i-
. period estimation for La Crosse is that proposed by Gupta and Nuttli (1976). This is one of the more conservative models for the U.S. east of the Rocky Mountains.
Calculations were also made using several other attenuation models. For la Crosse, peak accelerations for a given return period were similar. The LLL-TERA evaluations do not yet include site specific factors for amplification or deamplification based ca geological structure at La Crosse.
Due to compensating f actors, inclusion of this refinement would not necessarily translate into significant changes in the probability analysis. Upon review of the LLL-TERA results to date, the Staff concluded that the return period for a 0.12g or greater earthquake is of the order of 1000 to 10,000 years. More likely than not, the true value is closer to the higher end of this range. The Staff does not believe that more rigorous " confidence limits" can be specified. Reiter testimony, pp. 1-6; Tr. 124-126, 206; NUREG/CR-1582, Volume 2, Staff Exhibit 6, passim.
- 32. Dames & Moore conducted a similar seismic hazard analysis for
.the Licensee.2E[' Historical data and expert opinion were also employed and calculations were made for various attenuation models and 4
seismogenic zones. Earthquakes were assumed to occur randomly in time and space. Magnitude-frequency distributions were truncated at 5.0 on the lower end since asil liquefaction had never been observed at ES/ This. analysis is reported in the Appendix to the Dames &
. Moore " Response to Review Question," transmitted to the Director of Nuclear Reactor Regulation by letter from DPC dated July 14,
'1980.
. lower values. See also (n. 21, supra. At the upper end, calculations were made using both truncated and non-truncated magnitude-frequency distributions. Again, specific factors to account for possible ground motion amplification and/or deamplification were not included. The analysis concluded that the return period for a 0.12g or greater earthquake is approximately 10,000 years.
Using a reasonable range of variation in input assumptions, the results varied from 6,000 to 15,000 Differences between the Dames & Moore and LLL-TERA results stem years.
from differences in truncation points and other input parameters.
However, the results of both analyses overlap, at least in part.
DPC panel testimony, pp. 7-9; Tr.125,126, 207, 247, 339, 344, 358, 360-361, 365-370, 374, 376, 387-388.
- 33. Based on the foregoing, we conclude that the annual probability of an earthquake producing ground acceleration of 0.12g or higher at the LACBWR site is in the range of.10-3 to 10-4 34.
In addition to calculations at 0.12g or greater, Dames &
Moore made calculations relating return period to a range of peak 9
groun'd surface accelerations. Dr. McGuire, who conducted the Dames &
Moore seismic hazard analyses, testified that, as a rule of thumb, if the acceleration is doubled, the return period increases by a factor of approximately ten. Thus, if one went from an acceleration of 0.11g or higher to 0.22g or higher, the return period wonid increase from 10,000
. years to about 100,000 years.UI Tr. 388; see also Reiter testimony, p. 3.
It follows that, as the acceleration produced by an earthquake increases, the chance that such hazard would occur decreases.
- 35. Taking into account our earlier finding that liquefaction under pile supported structures at LACBWR is not likely to result from earthquakes producing 0.12g ground acceleration, it also follows that the hazard of liquefaction which might arise from a larger earthquake is lower than that accepted by the Staff (and the Comission) in the show-cause order as satisfactory for continued operation for a limited time period.
See p. 29, supra.
Reconciliation of Earthquake Hazard and Standard Review Plan Criteria 36.
In response to a specific Board question regarding an apparent departure from a 10~0 or 10~7 criterion accepted by the Staff with respect to other external events, Staff witness Levin testified that the 10-6 or 10-7 probabilities specified in the Standard Review PlanEI are used as guidelines for identifying l
E Dames & Moore est-imated that the threshold liquefaction resistance level for the LACBWR site corresponds to an earthquake producing an acceleration between 0.189 and 0.20g at the ground surface. Show-cause order, p. 4, 45 Fed. Reg. at 13850. This estimate may be low since it was made prior to borings taken in 1980 beneath pile supported structures which showed significantly greater soil densification than in the free field. Applying the above rule of thumb, return time for a 0.18g or higher earthquake would be about 3-6 times longer than for acceleration of 0.12g or greater (Board estimate).
El See sections 2.2.3 and 3.5.1.6 of the Standard Review Plan; see also SECY-80-409, Table H-2, September 4, 1980.
. design basis events such as earthquakes.
Events with lower probabilities need not be considered in specifying the design bases.
Events with higher probabilities, such as possible seismic events at LACBWR, require further evaluation and actions such as preventative and/or mitigative design features. As a rule, these are evaluated deterministically rather than probabilistically. The subject of these proceedings is a case in point. Having found the probability of the causal earthquake to be higher than the guideline, deterministic procedures were employed to establish whether liquef action would occur in the event of the assumed earthquake.
Levin testimony, pp. 3-4; Tr.
410-419.22/
' Finding as to Risk of Continued Operation 37.
Based on the foregoing, we find that the seismic hazard of an earthquake at LACBWR which might produce liquefaction is within the scope of the guidelines adopted by the show-cause order for continued operation, and continued operation pendente lite accordingly presents no greater risk, and possibly less risk, than the temporary operation perm.itted by the show-cause order.
i 22/ As a basis for assuming a size for the SSE for the purpose of its liquef action analysis, however, the Staff employed a probabilistic rather than a deterministic approach. The possibly larger earthquake which might result from a deterministic approach was one reason for our raising the SSE issue.
' IV. CONCLUSIONS OF LAW Based upon the Board's evaluation of the NRC Staff's Safety Evaluation Report', the affidavits submitted by the NRC Staff and the Licensee in support of their respective motions for sumary disposition and responses thereto, and the testimony of the Staff's and the Licensee's witnesses at the evidentiary hearings held at La Crosse, Wisconsin. on December 16 and 17,1980, we conclude that:
1.
Reasonable assurance exists that for an earthquake of up to magnitude 5.5 with peak ground acceleration of 0.129 or less, the soils under pile-supported structures at the LACBWR site are safe against liquefaction.
2.
Reasonable assurance exists that in the event that an earth-quake of magnitude 5.0 - 5.5 with peak ground acceleration of 0.12g causes damage to the crib house and underground piping, emergency cooling water can be provided for safe reactor shutdown using a dedicated safe shutdown systen.
3.-
Reasonable assurance exists that continued operation of the l
La Crosse Boiling Water Reactor without a dewatering system for the i
site will not endanger' the health and safety of the public, pending a final determination by the Board on the merits of all remaining matters l
in controversy in this show-cause proceeding.
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O
. V.
ORDER The Board having considered and decided all matters in controversy among the parties concerning the liquefaction potential of the LACBWR site in the event of a magnitude 5.0 - 5.5 earthquake producing a peak ground acceleration at such site of 0.129, and having satisfied its own concerns with respect to these matters, it is, this 24th day of February,1981, ORDERED in accordance with the Atomic Energy Act of 1954, as amended, and the regulations of the Nuclear Regulatory Comission, that the February 25,
.1981 operational date for a dewatering system at the LACBWR set forth in the February 25, 1980 Order to Show Cause is hereby extended pending a final determination by the Board on the merits of all remaining matters in controversy in this show-cause proceeding.
IT IS FURTHER ORDERED in accordance with 10 CFR 2.760, 2.762, 2.764,E
.785 and 2.786 that this Partial Initial Decision shall 2
become effective imediately and shall constitute, with respect to the matters covered herein, the final action of the Comission thirty (30) days after the date of issuance hereof, subject to any review pursuant
.to the Comission's Rules of Practice.
b The temporary suspension of 10 CFR 2.764(a) and (b) in certain proceedings, as addressed by 10 CFR Part 2, Appendix B, is not applicable to show-cause proceedings such as this.
t
. Exceptions to this Partial Initial Decision may be filed by any party within ten (10) days after service of this Partial Initial Decision. A brief in support of the exceptions shall be filed within thirty (30) days thereafter (forty (40) days in the case of the NRC Staff).
Within thirty (30) days of the filing and service of the brief of the appellant (forty (40) days in the case of the NRC Staff), any other party may file a brief in support of, or in opposition to, the exceptions.
THE ATOMIC SAFETY AND LICENSING BOARD OJw fEu)6Au Charles Bechhoefer, Chairfan ADMINISTRATIVE JUDGE w
Gr. George E. AMerson ADMINISTRATIVE JUDGE b
d Ralhh/5. Decker ADMINISTRATIVE JUDGE F
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.... APPENDIX List of Exhibits Admitted Exhibit
- Description Identified Into Evidence Staff Tr.
Tr.
5-1 Prepared Testimony of Leon 78 85 Reiter In Response to Board Ouestions, dated 12/5/80 S-2 Testimony of Howard A. Levin 78 90 In Response to Board Questions, dated 12/5/80 S-3 John T. Greeves, 79 92 Professional Qualifications S-4 Memorandum from Robert E.
79 88 Jackson to D. Crutchfield, dated June 23,1980, trans-mitting " Initial Review and Recommendations for Site-Specific Spectra at SEP Sites."
S-5 Letter.from Harold R. Denton, 79-80 96 NRR, to Frank Linder, DPC, dated August 29, 1980, trans-mitting " Safety Evaluation by the Office of Nuclear Reactor Regulation Relating to Liquefac-i tion Potential at the La Crosse Site."
S-6 Seismic Hazard Analyses, TERA 155 155 Corp. (NUREG/CR-1582, Vol. 2)
S -7_
Seismic Hazard Analyses, TERA 155 155 Corp. (NUREG/CR-1582, Vol. 3)
S-8 Single La Crosse Spectra 201 202 Intervenors I-1 Earthquake Research for the 135 not Safer Siting of Critical offered Facilities, National Academy of Sciences (cover page, pp.14, 15).
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