ML19270H173
| ML19270H173 | |
| Person / Time | |
|---|---|
| Site: | Maine Yankee |
| Issue date: | 05/21/1979 |
| From: | Harold Denton Office of Nuclear Reactor Regulation |
| To: | Burr R AFFILIATION NOT ASSIGNED |
| Shared Package | |
| ML19270H174 | List: |
| References | |
| NUDOCS 7906250133 | |
| Download: ML19270H173 (4) | |
Text
'
flf.D. O O R--
s s
t
[p *t%
UNITED STATES
. y *-
NUCLEAR REGULATORY COMMisslON
.{,..
, j WASWNGTON, D. C. 20555
/
l MAY 211979 i
i Mr. R. Peters Burr Vice President Fox Islands Electric Cooperative, Inc.
Vinalhaven, Maine 04863 I
Dear Mr. Burr:
I i
This is in response to your letter of March 19, 1979, regarding the shutting down of the Maine Yankee Atomic Power Station. This is one t
of five nuclear power plants in the eastern United States that the i
Nuclear Regulatory Commission ordered on March 13, 1979, to be shut down because of questions about the ability of their piping systems j
to withstand earthquakes.
Shortly before those orders were issued, it became apparent to NRC staff that analysis techniques which had been used in the seismic design of safety-related piping for these five plants were not in accord with proven and generally accepted engineering practice. The result could be overstressing of piping and supports for earthquakes which could reasonably be expected to occur during the lifetimes of these plants. The eastern United States is generally believed to be a region of low seismicity, when compared to the Western part of the l
country, but is not without significant historical seismic activity.
Attached is a map showing the location and intensity of earthquakes that have occurred in your region.
l Some of the piping systems involved could, if failure occurred, cause loss of coolant to the nuclear reactor.
In addition, systems needed t
to shut the plant down safely in that event could also be affected.
Thus, an earthquake of not extremely low likelihood would have the potential for causing an accident and for preventing operation of l
}
safety systems designed to cope with the accident.
We are aware of the critical energy situation which now exists in i
Maine and share yot.r concern regarding the prcmpt resolution of this matter.
Our objective is to review the situation in an expedited and disciplined manner so that the five plants can be returned to operation with assurance that this will not constitute a threat to the public health and safety.
2237 259 7900250/ 7 3' /f
F.
i Mr. R. Peters Burr.
k NRC staff has established a team which is dedicated to the review of the analysis of the Maine Yankee plant. This team visited the plant site at Wiscasset, Maine, on Tuesday, March 27, 1979, met with repre-l sentatives of the utility, and toured the facility. At this meeting, there was a discussion of the safety-related piping reanalyses per-formed by Stone and Webster.
In addition, a member of the NRC review team met with Stone and Webster in Boston on March 29 and 30, 1979, to review some details of the reanalysis prior to its formal submittal.
On April 2,1979 the utility submitted its answer to the March 13, 1979, Order to Show Cause, stating that the results of the reanalysis showed that no modifications to the facility piping systems are necessary.
In support of this, the utility also submitted an Interim Report by Stone and Webster dated April 1,1979.
In response to the staff's request, the utility submitted additional information by letters dated April 3, 12, 13, and 19, 1979.
NRC staff is reviewing this information to deter-mine whether it resolves the matter of concern.
After this information has been evaluated by NRC staff, they will be in a position to reconsider whether continued suspension of operations at Maine Yankee remains necessary. The staff's decision about possible resumption of operation will be made following consultation with and concurrence of the Commission.
Sincerely, A
Harold R. Denton, Director Office of Nuclear Reactor Regulation
Enclosure:
Earthquake maps of Southern Maine and Northern New England 2237 260
'k s
C[
I e
6 i
~
L-d 1
E3PJ 4
I i$*
II*
,4
,g
,f eauv} 21,6893 Yll 450 manes "f"'
't f
g
[,. st..:/ inn io.i66i n/ouEBEC
-,MAWE 1
fl 0 sj
~1 f~'j f 3,,,,,,,,,,l is,ir22 if
,3, J F, e t 9 4 Mll
,,o,,,, 3 X
3 f/uaH 1
W..
oc r u.... um i
j t
> >. '= a < => a.
... = < _ _ _
- m. =
- g;7;;;A; y, e s n.....,, m l
J.AN. 30,$.152 E
\\
\\
q i
.c.,
.AvesiL it.,is 1,4 Y-Vi teOV 4, tu t i V4 VL1 f
(
a aus' 20, isia n Vit e
,no e,iero a NEW e
i vERuONT s oEc n,iest un i,s h, (} _,o
/
itAMPStuRE '
44*
f 5sT E W i
/
08 1
i 1
2, DE C 20,24, IS 4 0 VII 6's"
,{
Poli lL Ardt M I
Oct 9,tS2S VI o APRIL 2 6, 6113 7 vi p\\
g
\\
i l
r io'
.g' CU"n."...<N(
- U-APHit,20 69 38 VII v
u.a 43
. l.__,.. __. f _
L
'."6 N
mov s, e r2 r um N
- i nAsi v / ___ __._ _ j Ws g
- nov is,or65 vm COMPILATION OF EAHTiloVAKES
/
MASS' e
3^****
U
[
rY oc t 's, ses t VII INTENSITY 32I OR GREATER q
[
f NORTilERN NEW ENGLAND
US *
- I N
/
.seaacnfio
\\
WESTON GEOPitYSICAL RESEARCll, INCs m
. r, - ~,.ConH.,,. I,ni..,,ov,,,, c..Ay i=
4,.
4 i
i I
ii
!!!!!!! li!!N
.;i!;;Hji,i:i i!J li ai;;;i::
liiii u :.
1.;i; m i
- i!!,
- il i
I I
~
C N
r%-
7s*30' tA 7t*
44*J(
/
e oCrS,343 y Fo*
69*30' 69*
- APhtL 25 IS20 M N
45*
/
/[
..e..
s x
(
44 taEW llAMPSillf1E 68*30'
'N
\\.'
w MAttlE
. I" Go MILES N
4:
4 /*
S A NGOft
'N.
'n rta tr. ser4 v O AUG 20.19te 3rt - Vit.
.
- JUL ID6F. N.
- g.....
~
5 DE C 20 2 4. s'J10 Ett j.rn DEC 23. ISSF,111 (,f f
- h
//
N 40 Mit.E S w
)
e,4 LLWISTON f
/
e l
/
to uitts
)
-w
= ocr m u-vi p
,,,,,., o,,,,,, m. x /
/.%
4 4 gel y,,,,,,
/.
/
r r
.~.N BRUH 5wsC M.,. /.....
S 3,,g ROCMLAND
/
I s e, a..,,,,, a,,
..... ms...#
%....... s... i )
N Poni No *
.s2
[p g
\\
A p. Y OH sa f 6 I
2 S
SE P T. 19.,95 s X N
O s 30 2o 30 40 uit t s
'(
tum= mu s
=a-==>s
/
f
- g
.s
..,_L......
~~ 4 4 j
COMPILATIOt1 OF E Af1TilOUAKES fo.33
/
f.
roo t suoutie
\\-
[N SOUTilEftri M AIPJE
- s. <
78* n tu s. euso v-Vi 70*
69*30' 43*30' t)y
[s3 49' 6o*30' WESTOtJ GEOL *llYSICAl. Tif SE AllCH. tfJC b
.... s. o n q:=9 GEED ea gL a