ML20215N142
| ML20215N142 | |
| Person / Time | |
|---|---|
| Site: | 05000000, Diablo Canyon |
| Issue date: | 02/28/1977 |
| From: | Rusche B Office of Nuclear Reactor Regulation |
| To: | Boyd R, Case E, Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20197J003 | List: |
| References | |
| FOIA-86-371 NUDOCS 8611040353 | |
| Download: ML20215N142 (3) | |
Text
P I
f d270~
\\
hb 2 8 n17 "E):n9p mv" rnr-E. C. Case, Deputy 9f rector, Offico of Muclear Reactor reculation
". S. "oyd, T' ire.ctor, Division of Prn !nct "eracrnnt H. P. 9enton, Director, nivision of Site Safety and Environrental Snalysis
". F. Niermn, Director, nivision or syst.:me. safety V.
Stello, nirector, livision of c, rating 'Joactors o
PfN ' -
9en C. eusche, ":f ractor, 'iffice of Nuclear % actor "eqnl a ti on Si?sJECT:
al AEl.G CWYM In order to assure that w." do all ue can to orovide the Camiission wit'1 viable options concerning the licensing of t!n Diablo Canyon
,3 2,m.ss, nlant, consist'nt '11th nublic safety demands, I renuast that vcu e
rmt vi th M.' Nginning at 4 Rn o.n. on Tueda !, " arch.1, 1977, in "oon P-M
to discuw various creasures that night be taken at this tim. Oth 'rs that riculd itt,d are '.'. tieYounq, F. Schroe<!er,
'ol lt r.
m sello, 1 S tolz, . f i l i so n, 'J. Cmmi l l, C. S terin,
s'. % fna m..'. 'ni ch t, I. S it' t 'il, ". ilena, . Eiv n'iu t,,1 Tour tallo tte,
,r1I Tavis.
I '.>ould ax:'ect to discu3s thc consible entional course of action hrI%! '-law, nr.d to "' rains tern" So' tnt cour;r of a
,ctier ei" *
. trnoo'it tr fruif.irn, and to devnlop othnr cour ;or,
,if 1: tion tw nie '- avai161e to us at this tir'c.
I 'muld exnecl tn> nectino to continus into tb: nvenino n-lono ar. is "arranted t'i ear orocror.:.
Te licno +- ir na'ior a -trimurus n' fort to crnl.'re th9 Siablo C m io's ilar' in -var r s" :ct, >xcr it for t bmn m *.t'rs r-lc tof 'e
~. i c:.i r i. ;i.
i.ril 1. I " 7.
Ii r ic14d r '. r,alution of
+..
-.jc
,1. -
c.,
- .. t.. i., n, y;. o,
.1 3. -
.))
i"'-
t.'
~' : '-
r
,L-r
- f r-l i c-
^ ' ' - 1r4 e.ur ri' i 1, r o all :U si-
,cc.
1i
/
....ix vc r N i likely
ru',
- " ' Man li n i'lr. v,r "
. i ej.
,-mj p -.. *
-.n, i,
8,i
= '
.pi.e, 1-y i
c r ;' a i.,
3,-:7-1-
n-
- ]j 3
.pe]p ij
,( [
'j. p g.j a f' ~.
lyr.gev f
.q q pr a
se 4 -
] f,i p. gf r,
r g.
<i
<n c,p
>pe, M" * 'l 0611040353 0610*r_3 PDR FOIA PDR HOUCH96-371 or.c "
cu o.. =.
772210059
- d... * '
- . i a
reen. Arc 3:e (a,. 9.ss) AscM o240 1Y u. e.
ov a==sav enimvine opricss ee,4.sa see g
4.g
r p-
~
)-
l Multinle fddressac:
2-46 2 s m
@4 has advised m of the followino cours'e of action that micht be talen to provide the Comission with an optional course of action that might be folloved if the situation described above does develoo:
(1) Pr ss the licensee and staff to cmnlete tha seismic reanalysis as soon es res';ible.
Even with L,est efforts uc do not exnect final resolution until late this year or early next voar. We have opti'nistically nradictad ACPS meetinas in July and Sontember uith a weat hone that we can convince the fC6S to issue an interim l~tter in July to nennit consideration of a partial co.1er license hv the ASLP.
(2) ec';olve all non-ceismic natters and issue a suitable SER Supnleient in feril or earlv May. These matters include:
(a) Safety Tech S9-es(b) Environmental Toch Specs 3--
(c)
Encroence "lan (d) liian Enerny Lino Euntures (n) 5:rndix !
(f)
~mact >r l'anel Surnnetc
( o,)
W..:S (h)
Fir 7 Protec tion (1) ^ualification of fquim.>nt (I) Tnrr en Prorection
(' )
- cr m,:1 <-:c.
(1)
~ v" & r c.orirarian
(-)
- t y.,41
'~
p s.ti 3
- . i. T c.ti;
'rct'e m M ' '.
u.
, w :.. r ' M -c.i n,. r re., ry,
(n
. y g., - n
- p. 31 p H n",,,p,.
,il i t:r m n e. " e t 'n r *
+ ' -' i r rie' 3: :f.
s i c. d,
-';'. inn for!;
$ro'-e iliti f'r vreior n imic avend. a.:.! or); Ailitic'. for sa f r '~nn" nf '*" " lM in thoe avents.
9SF could do t',a fon*:r >'i th (hono Full v) f.'
a ric = *.
eu a~ a -=
- m.
oaee>
Ferns ABC.S t a (Rev. 9 5 3) AR(St 0240 W u. s.oovsemment peserine oppsces sete.eae see
)
Multiole Addressees fEb /
Mil assistan.e of the USGS cr at least its non-disagreement with the staff results. DSS could do the latter with the direct participation of i'r. I:aaaark.
The advice, assistance, and/or concurrence of T'SP would be umful. Thn report of tha analysis should bo issued in the Anril or 'Mv SER Sunnlarnent.
('i) The SER Supplement should summarize all the results of the seismic reanalysis available to that time to indicate the adenuacy of the nlant for a 0.59 event, and the adecuacy of certain nortions of the plant for hicher valuas.
It should also indicate the "nutlook" for the results yet to be obtained from the licensee's roanalvsis program.
(r-) The SER Suor.lcment should, if appropriate, conclude on tho basis of the seismic crobability assessment that the olant could be licensed for operation for a period of a year if the regional welfare of the public warranted such o,n' ration.
If the ACRS aqreed, the matter could then be niaced before the ASLB for consideration.
I" S The above is the nossiolc courso of action I unuld lika to discuss.
If general aqrcrmat i reac't,d t'et it, or sono nodified or different ancroach, should La nursued, I ucul ! hopa that alianHent of staff resources to accomlisS t',n tisk could also be addrr ssed an ! rusolvM.
ot oy he Ban C. "uscha, 'Ji rector 3ffica of "uclair 9actnr "agulation cc:
t'. laYouon r, s hron t e c
'Ull 'r Distribution
,'w a l li
'fr6cket Files 1
"r l -*
NRR Reading
'lliv ED0 Reading
'v"# H RCDeYoung Reading m n."..
BCRusche
,t.
sn:.t
!. Si! -il
.T ~ n 1 Fit r.L U '
?. Tourb'lh uc 1
lav 4 n
DD:P HRR
.,,,c.
BCRufche....
RC sjt
.RS EGCa
_. ;NEN e.....
2/28/
Forma AEC.3ta (Rev. 9 53) AEO4 0240 W u. e4 eovenwassa? Paintine 'orreces nova.ese-eee
- C
\\
)
DISTRIBUTION:
~
MAR 141977 Docket Files: 50-275 50-323 NRR-Rdg SEB-Rdg Docket Nos: 50-275 50-323 MEMORANDUN FOR:
C. J. Stepp, Chief, Geosciences Branch Division of Site Safety and Environmental Analysis FROH:
I. S. Sibweil, Chief, Structural Engineering Branch Division of Systems Safety
SUBJECT:
DIABLO CANYON SITE, EARTHQUAKE OCCURRENCE PROBABILITY DATA (SER:1111)
As a part of our overall effort in the OL review of.the subject plant, we are proceeding with Dr. Newmark to assess a range of failure probabilities for Category I structures, systems and components given occurrence of earthquakes of varying "g" values at the site.
In this connection, Dr.
Newmark requested that we provide him the earthquake occurrence probability data (or recurrence periods) associated with a range of maximum ground y
motion "g" values (up to 1.20g) pertinent to the Diablo Canyon site. The availability of these data to Dr. Newmark within a week or so should signif-icantly expedite his work. Therefore, we are requesting that the Geosciences Branch provide the following data to the Structural Engineering Branch as soon as possible:
a.
Probability of occurrence for an earthquake resulting in an effective maximum ground acceleration of 0.759 at the plant site (most urgently needed information):
b.
Probabilities of cccurrence of earthquakes resulting in effective meximum ground accelerations of 0.2g, 0.49, 0.5g, 0.69, 0.8g, 1.0g and 1.29 at the site.
If further clarification is needed regarding the need and technical aspects of. these data, please contact Dr. Newmark directly in order to expedite the work.
I. S. Sihweil, Chief Structural Engineering Branch Division of Systers Safety cc:
R. Haineman
' ()
J. Knight "I*
Q[2-W. Gamill R. Hofmann D. Allison n
u,.
m e-,'
udd:stu
"c=*
_.x22BQZ..
f,g'nSS SEB_:
DJENG p 3999882 ISihueil 772210054
.03[(p77 03/N/77
=an
- A a5 N:c romu us <,.763 uncu 24o
- o..........,,,,.vu...,ne...~
58 SW
)
.r s
)
N' DIJ dIBUTION:
L/1NTRAL FILE NRR RDG MAR 2 4 197 I GB RDG DSE RDG 1
MEMORANDUM FOR:
I. S. Sihweil, Chief, Structural Engineering Branch Division of Systems Safety J
FRON:
J. C. Stepp, Chief, Geosciences Branch, DSE
SUBJECT:
DIABLO CANYON SITE OCCURRENCE PROBABILITIES Your memorandum dated Mareh 14 requested that my Branch furnish you several probabilistic computations of ground motion for the Diablo Canyon site. My Branch does not have tha necessary data to make these computations. I an attempting to make arrangements for the computations to be made and estimate that it will take sixty (60) days or longer. I will keep you informed of our progress.
' Original Signed by J. C. Stepp J. C. Stepp, Chief Geosciences Branch Division of Site Safety and
~
- Environmental Analysis cc:
W. Cammill J. Knight R. Hofmann D. Allison le.
l o
ci;3 L
s ir 'I
- Y y8 a"'e =
- _.DSE
.G su """ = >
-J p;sb
' ' ?.'10052
_ /22/n _.
i e
om.-
"
- l'*. We m 3M
- ====n"~~=~!?"'~"~=="'~'~-~~~
b*
F eo I
fjc)4 MAR 2 41977 HEMORANDUM FOR:
D. Eisenhut Assistant Director for Operational Technology, D0R FROM:
L. Shao, Chief, Engineering Cranch, COR
SUBJECT:
DIABLO CANY0tl STATUS REFORT The ACRS received an update on March 11, 1977 concerning the Diablo Canyon Seismic Design Bases Re-Evaluation. Dennis P. Allison. Project Manager, briefed the full committee on a two phased approach..aich is presently being conducted by Pacific Gas & Electric Co. (PGSE) and its consultants. PG&E is in the process of reanalyzing four major structures and the associated mechanical contents. Paralleling this effort, PG&E has chosen to pursue a probabilistic approach in evaluating a short torn solution which could possibly ' lead to.a conditional operating license.
DSS has approved the PG&E specification for the seismic review of major structures for the 7.5 M Hosgri Earthquake. The magnitude was determined W
by the U.S. Geological Survey. The mechanical specification is currently under review. The latest schedule indicates that a February 1978 PDD may be realistic. Present plans include a briefing of the ACRS Subcommittee Staff at their June Meeting. This meeting will serve as prep for a projected July full connittee meeting to give members an opportunity to study PG7.E's work.
The prinary concern of all those involved has been in the proper specification of the ground motion. The ACRS has received a range cf com:ents and recommendations freci its seismic consultants. The subconnittee has asked the NRC Staff and the Applicant to provide responses to the technical issues raised by the ACRS consultants. The NRC Staff has accepted both a Newaark and Blume ground spectra. Both of these spectra will be considered in the re-analysis. Dr. Hema.4 has concluded that an effective acceleration of 0.759 is acceptable.
The evaluation of the plant's capability to withstand tne 7.bM earthquake is being coiapleted considering the following changes to the original analyses.
1.
The new 7.5M spectra developed by both Elune and Ne mark will be considered usino a reduced effective input to account for large foundation effects.
(Tau Effect) 2 e
Contact:
"b U
ii. Levin Qd NJoO I
-,a*
[U A. A.. W b.
onn *
....c..
A-Q l
=cmm m<,.m m m m
- ..................,,....-.ma
Ia s.
1 D
. 2.
77, structural damping will be assumed.
3.
The elastic response will be reduced for cases where ductility can be justified.
4.
Torsion will be considered for an eccentricity of 7f,.
6.
Three components of response will be combined by SRSS rather than the absolute sum of one horizontal and one vertical as defined in the FSAR.
6.
Actual material properties will be used as substantiated by test results.
7.
The amplified floor response spectra will be smoothed using a modified procedure which accounts for the effects of new mathematical model properties due to the new structural strength considerations.
8.
Fixed base models are permitted for shear wave velocities exceeding y
3S00 FPS.
Serious concerns have been addressed by ACRS consultants who have studied the re-evaluation mathodology.
J. E. Luco and H. D. Trifunac feel that-the design spectra is 30% to 50% lower than that expected for a 7.5M earthquake. They feel that the correction for foundation size effects is unsubstantiated. Also, the damping and ductility assumed may be too high. The complete process of considering these effects leads to a total reduction in response of a factor of 2.0 to 2.5.
Luco and Trifunac conclude that a more detailed and rigorous analysis is required to verify the assumptions being used.
J. T. Wilson and M. P. White feel that a 7.5M earthquake may be too high.
J. N. Brune has suggested that seismic waves can te focused in a narrow beam of high frequency energy which can lead to ground accelerations of several times the acceleration of gravity. Ilowever, T. W. Pickel feels that the act effect will be small.
Tiie range of concerns is Jiverse. They will be addressr.d by PM E at future ACRS committee meetings. The Engineering Cranch is studying the evolution of the Diablo Canyon Safety Evaluation to effect a sv.coth transfer of rcsponsibility upon issuance of an operating license.
DISTRIBUTION:
Central Files EB-Rdg EB-File Number L. C. Shao, Chief Those on Concurrence Engineering Branch Divisio,n of Operating Reactons7
.EB.: DOR..k..EB:DQh.
.. EB; h3 bR EB:).._
o f>El* I* Stello co n.m.s HLevin:dr. -
.GBacchi
.RStuar_t
.Wiazelton
_LS.hg 3/22/77 13/[/77:
3/87 3
33 477
_3/7g77 NRC FORM 318 (9 76) NRCM 0240 D u.a. oovannuawr eninvine orrects te7e-eseda4