. _ _. .

-~

, . s 4THIS DOCUMENT CONTAINS

#P00R QUAUTY PAGES $?C h.--

'

1

'4 ',, ~ 6 ;ggI k ^ )-

-28-^

Ott;Q[theSeefef,7yUNITED STATE 3 OF AMERICA o. i

8NUCLEAR REGULATORY. COICIISSION L. 37, Service dN

BEFORE THE ATOMIC SAFETY AND LICENSING APPEAL BO P,

)In the Matter of )

).PUBLIC SERVICE COMPANY OF ) Docket Nos. 50-443NEW HAMPSHIRE, et al. ) 50-444

--

(Seabrook Station, Units 1 and 2) ))

NECNP RESPONSES TO APPLICANT'S INTERROGATORIESo

Attached are Dr. Chinnery's answers to the Interroga-

tories posed to NECNP by Applicant Public Service Company

of New Hampshire. Dr. Chinnery's affidavit is still beingi

prepared and will be forwarded shortly.

Respectfully submitted,

(. - ,- ,-

. ~. / v / ,& :- V . _ . . . - , ,

William S.fJordan, III . yHarmon & Weiss1725 I Street, N.W.Suite 506Washington, D.C. 20006

: (202) 833-9070

Counsel for NECNP

Dated: January 6, 198)> .

8101090 %&

. . - .. . . .

o e

tJ . .

,

. . .: 2 ..- ._._.u . u. _: _ _ : _

Lk N and east of longitude 72"'.., together with that part of Massachu-

setts and the Atlantic Ocean bounded by latitudec h2 and h3 N, and

longitudes 69.5 and 71.5 W.

Reference:

1. Chinnery, M. A. and Rodgers, D. A., Earthquake statistics in

- Southern New England, Earthquake I!otes, volume hh, pp. 89-103,

1973

.

. .

I have not retained tne workaeets used in the preparation of my

197h testimony. However, subsequent to then I have reworked the problem

in more detail and published the results (see reference 1 belev). That -

paper contains full details of the data catalogs used, the nethod of

extraction of the data plotted, and the areas selected for study.<

Reference:

1. Chinnery, M. A., A comparison of che seismicity of three

regions of the Eastern U.S. , Bulletin of the Seismological

Society of America, volume 69, number 3, pp. 757-772,1979

I

_ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ - , - - _ _ _ - - - _ - - - - - - - - - - - - -

h

Ot:J &nO**'Or T,0 Qi d o L [O!! 3.

I

i

i

!

+

8

_ _ _ _ - _ _ _ _ _

a - . - - m.. s. ,e - ,-

O

e

e

L

F

1

h

i

r

I

Ie

- ?-i i

.

I.

r

h

I+

to questica .$. |e cee answt-

!.

$

Ii

J

8 )

>>

t k

IL

F

t'-

t

T

e

V

5

ba

i

L

e

L

9

P

k

4

.

t

i.

'

I

t4t.

e

.

.

1

- i8

&

!-

o

- %.

I

7'1

r

T

7

h

g .

I

f

- ._ , . _- , . , __.. . . _ _ _ _ - , _ .. , , _ . _ . ,

. .

,

of the term " discrete seismic zone." In fact, there is no

generally accepted definition for such a zone in the Eastern

U.S.

In the absence of such a definition, it is difficult to

define the boundaries of any seismic zone. My particular.

selections are certainiy not unique, and I do not ascribe

any particular properties to the boundaries of the areas that

I selected. Subject to the response to Question 15, I do not

expect that choice of different boundaries would make a

substantial change in the results.

.

- .

. s L a.t io;.a r,, in ;it.2 _..re m. . s aw e. tde;.cca in tnt .titerature unat

I

this r.ay not be entircl; 7alid, but ce cow 30 little about, any p0csible

lack of stationarity that we are forced to make this assumption.

Within any given area, a record of earthquake activity over a very

long period (theoretically infinite) vill completely define the long

term characteristics of the' seismicity in that sone. Records or ai

shorter length vill lead to estimates for these long term characteristics.

We vould clearly like to have as long a record as possible in each

zone, but such a record is only useful in so far as it is relatively

complete. It is therefore reasonable to use as much of each catalog as

appears to be reliable. We attempt to determine the number of events at,

each intensity (or magnitude) value per year. Comparison of different

areas does not require that the sane lengths of record be used, if the

stationarity assumption is valid.

,

O

T- .

This report is not available to me, and my letter quoted only from

recollection. However, this statement has appeared in the following

places:

1. Deposition of Donald E. Vandenburgh, containing ansvers to

interrogatories propounded to the Public Service Company of

New Hampshire by Elizabeth H. Weinhold, Answer 15

2. Applicants' Direct Testimony before the Atonic Safety and

Licensing Board, page 15, line 12.

Both statements refer to the occurrence of Intensity VIII on the

bedrock of the Seabrook site. In view of the requirement of NRC criteria

10 CFR Part 100, Appendix A, that the largest earthquake associated with

the seismotectonic province including the site be ascumed at the site,

these statements are directly comparable to the reference from my letter

quoted in the question.

_ _ _ _ _ _ _ _ _____.________ _ _ _ _ _.,

,

province either in 10 CFH Parr, 100, Ap1'endix A, or in the scientific

literature, I cannot answer this question directly.

The Appendix A definition is "a region of the North American conti-,

|.

nent characterited by a relative consistency of the geologic structural

features contained therein". In my opinion, this definition is so vaguee

as to be vorthless.

If_a province can be defined that has uniform sciemicity character-

istics (I do not necessarily argue that this can be done, or that this,

corresponds to the Appendix A definition), then data from any portion of

the zone vill define the characteristics of the whole zone. Using this

b-

approach, the Boston-New Hampshire seismic zone (see question 2) may be

regarded as a portion of a larger undefined province, and validly used

to estimate risk at the Seabrook site.

The above approach is valid if regions of uniform seismicity exist.

In this context, we must define the word " uniform" in the following way:

Suppose that the long term characteristics of the region can be suzzarized

by the frequency-magnitude relation:

_

log U = a - bM

vhere H is the cumulative nunber or enrthqusken with nry;nitude M or-

g 'ite: po t- u, : ' m, .- >'! b em ;t: m. 'avm aniformity nu '-

.

.- ,

Ir rei; tens of uniforn seiscicity do not, exist, then nat only is the

sb ave approach not, uliti, but nica e.ny use or- ni.scic or tectonic provinces

becomes meaningless.

.

,

|'

|__ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ . _ _

_- . _ _ _ .

*.

$

Ihe bacia for cy spiniona expre sed in que:st. ion 12 ::ac developed

from reading the scientific literature, various informal discussions

with seismologists, and participation in the study " Seismic IInzard

Analysis Solicitation of Expert Opinion", conducted by TERA Corporation.

None of my published papers have addressed the problem of the

definition of a " tectonic province".!

i

I

&

t6

e

9

-

.

the estination of the se 2 saic rio., at . . . _ - .3cabroa. site is

not dependcat on the particular choice of a " tectonic pro-

vince." However, the choice of " tectonic province" may

influence the size of the risk associated with this site.The Boston New Hampshire zone is not to be identified with

the " tectonic province" containing the Seabrook site. See

response to Question 12.

.

:-m,.us.- M ,w 4.mb.-k +e4se4e.- EAJ---- J.- .--WA,h46Mr hs- M M i.+mE+? ++-i4u.-*46+.d4-. ---+dW 44_

#

l'67tV. .[JS L.n.

, -

4

h

|'bb, [ N .yC lil~ ' *l. .i '.' * C 113 I 4 .,) , 15 1y eln'[Cilli)::J G D))dl' U ' O .9 G S[C]10

1'

&

1

$

1 '3

$~ :m a m;t-e>- ri rpp,u; or

' "j _

l.,

Im

:i

ie

$

it t

4

i5

,

I4

9

i,

iIiis

11!

|4

i

!

i

4

}

r

. i

.

11 m

4' *

ia1 81

!1 |f4i

!b

4

i4

|

1

4

3:

.m

e'?-

_ . _ . _ _ _ _ . , _ - _ . _ - . - - . . . . . - . . , _ . _ . . . _ . _ _ - . , _ _ _ _ . . . _ . _ _ _ _ _ _ _ _ _ ____. ._.. . , _ _ . . _ _,_ . . ~ . _ -, - . _ _ . , _-

,

1. Definition of the Safe Shutdown Earthquake.

A?pendix A defines the SSE using the terms " based on an evaluation of

the maxinum earthquake potential", and "the maximum tibratory ground motion

for which certain structures, systems and compsnents are designed to rema!.n

functional". This definition has to be interpreted as the largest earth-

quake possible during the lifetime of the structure, at a 100% probability

level.

In my opinion, the current state of knowledge in seismology is not

sufficient that such an absolute declaration can be made, and I do not

anticipate that this vill change in the foreseeable future. To put this

| another say, at any site we do not know enough that we can completelyl

rule out the occurrence of an intensity XII earthquake, even though weI! think it may be extremely unlikely.

If this is so, then associated with any choice of SSE is a level ofi

!

risk (or probability that it may be exceeded). In my view, Appendix A

should specify an annual probability level which constitutes an acceptable

level of risk.

For example, the definition could be phrased as follows:

"The Safe Shutdown Earthquake shall be that carthquake which shall

be established as leading to actual failure of critical plant components

. th an annual probability not exceeding 10~ The conputation of thea .

f.iluu p e9 + 1 L t ,, -Ki<s . - ta t c f the cultipl :n? icr of two individual

, - ' . g,.,.

:I4 u (L -

,4-io / - -

(ii i the prabubili.. 'at e'itical pla..- e v.1 ' matc ill fail wen

subjected to the vibratory ground motion to be expected at the

site, on a conservative basis, as a result of the occurrence

of the Safe Shutdown Earthquake.

The critical plant components mentioned above are those structures,a

systems and components that are necessary to assure

a) the integrity of the reactor coolant pressure boundary,

b) the capability to shut down the reactor and maintain it in a

safe shutdown condition, or

c) the capability to prevent or nitigate the consequences of

accidents which could result in potential offsite exposures

comparable to the guideline exposures of this part".

~IClearly, the choice of the acceptable level of risk (lC in the

above example) needs careful consideration by the HRC. In my view, if

safety factors in plant design are established to be high, a formulation

such as given above is not likely to increase, and may actually decrease.

the structural requirements needed to account for seismic risk. Certainly,

it is possible to approach this definition on a sound scientific and

engineering bacis.

,

_ _ _ _ _ _ _ _ _

vic .c.a s ale:atra2turai ::: Luces er .ai: _. , n u. _ f.e : ae . . >. s

vith this definition:

(i) the term " relative consistency" is completely ambiguous.

(ii) there is no set of "tectonie provinces" in the Eastern U.S.

that is accepted by a majority of seismologists and geologists;

furthermore, I do not anticipate that agreccent will be reached

in the foreseeable future.

(iii) the context in which this definition is needed is in'the

description of the distribution of earthquake occurrence,

i

In the Eastern U.S., and in parts of the Western U.S., there

is no clear correlation between geologic structure and earth-

quake occurrence. We do not know which features of Geologic

structure are related to seismicity, and which are not.

In my view a more useful definition of a " tectonic province" would

be as follows:

"A tectonic province is a region of the North American continent

characterized by a uniform distribution of earthquakes, in which an

carthquake of any given sine has the same probability of occurrence

at all points within the province. The uniformity of the earthquake

occurrence in any given tectonic province shall be demonstrated and

Justified using all available seismolo6 cal and geological information.I

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

. - - - - - - - - -._

.

" ;- h - - - - ,,;- , .1 ,.

,_ , ,

region shall be not less than 100 kn, and shall be

selected using all available seismological and geologi-

cal information."

,

4

.. .. .. .

_ _ _ _ _ .

|

l

..6L2u . . . . : :: w w . u a::c.. - :; ..e . n c a. : :,.

hard ta prmee or tect, and nei ge:arall;. acceptcl by the ccientific

community.

2. The historical record of earthquakes in this area is a very unsatis-

factory data set. The completeness of the record is a complicated

function of location, time and maximum epicentral intensity. Our

knowledge of this function is minimal, and any interpretation of

the record has a strong subjective element. It appears, for example,

that modern instrumental recordings by the Rev England seismic

network indicate a pattern of seismicity that is different in many

respects from that indicated by the historical record.

3. Partly, perhaps, because of the weakness of the historical record,

attempts to relate the overall pattern of earthquakes in IIew England

to geological structures have been essentially unsuccessful. There

is a strong suggestion that the 1940 New Hampshire earthquakes were

related to the Ossippee Mountain ring dyke complex, but it is clear

that most other events cannot be easily relate <1 to such well defined

structures. Because of this, it is difficult and perhaps impossible

to use the historical record to define where future earthquakes are

likely to occur. The assumption that future large earthquakes vill

occur only at the r.itea of hictorical lar6e events is very questionable.

.- . . ~ . -. - - - - - . - _ . - .._. . .

. .

,

.i.

t

i

t,

!,

?

i ;.

!,

),

I;

;

ii'rec r., o q+n e w _ e c..c ;;p x - 'u t z e L .; . :.L uc.g ;tceu1

I-

s i t. " . |'

t

i I

! In ny view, the above points are adequately cummarized by the |4 ,1 .

] ctatement that "we know remari: ably little about earthquakes in the New {! I'

England area". !,-

,

i !

[.

I i

' [',

i

f.

I

i

i,

i

ii

!.!

!

!

l.i

{.

!'t6

'I

j i

4-

.

.

9

-

,

'I

h

it

* f! I* .

#

W

.__ _ . . - _ . . - . - - , . . , __ .-. . - - , _ . _ , , - . - _ . . . _ - . _ _ , . ,. - , . . - - , - ,.- . ,

. . , _ , . - - - . - - - - - . . - - - - . - - - - - - - - - , _ _ - _. ,. -

e ,e 'N

s..

O LA 'I EI O N '2' C U k V.'. . NdC tf'u-y g j, [y;; )g,,

i

<

g

.

'

|

|i

!.

,

!'

- - . . . . . .

'' ._m___.___.m__ _ . _ . _ _m

'

<

/

f.r

a

f

f

a n:_a.we. ::n ce p2.ec ;. _ . .r_ na . ...c_, n;

.i) A ev:.aer, aL,ic e s ure.u c. i.ne pt . .alli ty Lii a ; :!1e aedif.

acceleration would be exceeded during the lifetime of the

structure.

(ii) A detailed evaluation of the engineering " safety factors" used

in construction, i.e. a conservative estLnte of the probability

that a critical component of the structure vill fail if subjected

to en acceleration greater than the design acceleration.

(iii) An established " level of acceptable risk".

If the product of (i) and (ii) were less than (iii), then in my

opinion the plant could be designated as " safe".

,

Let me add three points which emphasize my opinion:

a) I do not believe that the way to solve this problem is to seek

for a Safe Shutdown Earthquake which is so large that its

probability of occurrence is exactly zero. I do not think

this can be done at present.

b) I feel that the safety factors built into the structure are an

essential part of the assessment of seismic risk,

c) I would not, perconally, require a prohibitively low " level of

acceptable risk". In my view this risk should be made conparable

plant (e.g. other naturalto thoue ethe. rius im ah sa in . .

.).~ '

,

:

,

4

P

_ _ ;_.c. - . _ _ . c. n t s : u i s. .

questions. However, let me repeat the basic ideas here.

I'y arguments are brM nn one Ore-!::e, e::d this is that we do noti

know enough about earthquakes in the Eastern U.S. that we can (with 1005 [

certainty) state that an intensity XII could not happen r$t any site,

even though we may often think it would be extremely unlikely.

Then, if 10 CFR Part 100, Appendix A is interpreted as requiring

the selection of an SSE which has a zero probability of occurrence;

during the lifetine of the structure, there is no alternative to making

the SEE at all sites equal to the largest possible event, i.e. XII.t

However, I do not believe that 10 CFR, Part 100, Appendix'A requires

such a drastic interpretation. My reading of these regulationn is that,

the SSE is an event which can be demonstrated as being extremely unlikely.,

Unfortunately, this interpretation requires that " extremely unlikely" be

j defined in some way, and the writers of Appendix A vere clear 3y unwilling j

or unable to include this definition. This is a p/incipal change I ,,

e

' vould like to see in Appendix A (see question 17).

All the above is independent of my so-called " theory of probability".

This only arises if try basic premire is accepted, and is one way to

atte mt to esu ,te tho - oh ,bi l ~ + ! er. of n~'u ~en ce o f lit rge e irthquakea .

/

'>

t

\

r

--

b.

-he s.

.g w1TED& own <t

~

J AN - 6 M81 > -

h g, : d tre secetsf haawg L 59" sy

b 7

o> q/

PUB LIC S E fs'Ir" r< "" ' r Or ) W. ' > 50-'43L.O; E!:,:2. a i tk , cc aJ. > 5u-4: 4

)(Seabrc.ok Station, Units 1 )and 2) )

)

CERTIFICATE OF SERVICE

'I hereby certify that copies of the "UECNP Responses

to Applicant's Interrogatories," Iave been mailed postage

pre-paid this 6th day of January, 1981, to the following

parties:

Alan S. Rosenthal, Chairman Dr. John H. BuckAtomic Safety & Licensing Atomic Safety & I,icensingAppeal Board Appeal BoardU.S. Nuclear Regulatory U.S. Nuclear Regulatory CommissionCommission Washington, D.C. 20555

Washington, D.C. 20555

Frank Wright, Esquire Assistant Attorney GeneralAssistant ^*torney General Environmental Protection DivisionEnvironmc L.1 Protection Office of the Attorney GeneralDivision State House Annex, Room 208

Office of the Attorney General Concord, New Hampshire 03301One Ashburton PlaceBonton, Massachusetts 02108 * Thomas G. Dignan, Jr., Esqbire

Ropes & GrayRobdt A. Bachos, Esquire' 225 Franklin Street

i n', ,!;, na ';n a , Spielr' , ' 'ilo E v an, ",v :ri ioettn 02210

~

;

.,

, I* g a 4

'

{'* *

,

#8'.

<,

h

LOO ' . . t' .i; i,

,3

f,

#$

e

I

>

,

fExpress Mail.*

s

s

n

i

i

>

l