ML20056B656
| ML20056B656 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 11/16/1971 |
| From: | Grier B US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Wachter L NORTHERN STATES POWER CO. |
| References | |
| NUDOCS 9102070678 | |
| Download: ML20056B656 (3) | |
Text
.____ -__ _ _ _
.o i
trkeY 5 '
~~
i
- 5' reg
{
f UNITED STATES L.'
I.
ATOMIC ENERGY COMMISSION l
DIVislON OF COMPT. LANCE I(
(
[
'I nEGION lif onn p too RoosEVEl.r ROAD b,,,
Gt.EN Eu.YN. I5 t.lNots 00137 cela) ess.asso November 16, 1971
[.",:
13,'.
ti.
Northern States Power Company Docket No. 50-263 p,
f[
ATTN: Mr. Leo Wachter, Vice President Power Production and Systems I
1 Operations p,,
414 Nicollet Mall C-Minneapolis, Minnesota 55401 S,'.
G.'
Gentlemen:
p This letter refers to the inspection conducted by Messrs. Feierabend and
[h..
Seyfrit of this office on September.13 and 14, 1971, of activities at
[3 the Monticello Plant authorized by AEC License No. DPR-22, and to the j,
discussion of our findings held by Mr. Feierabend with Messrs. Larson,
- l..
Jacobson, and Nevinsky of your staff at the conclusion of the inspection.
'J The treas examined during this inspection pertained to the unplanned reactor scram which occurred on September 5, 1971, and resulted in
(
initiation of the Emergency Core Cooling System. This uter was reported M
to the Division of Reactor Licensing in your letter of Occober 5, 1971.
Q i
The specific areas examined by our inspectors included the sequence of L
events during the occurrence,,gur evaluation of the cause of.the occur-p rence, and the corrective action planned and implemented. Within these i
areas, the inspection consisted of examination of pertinent procedures, i
records, interviews with plant personnel, and observations by the inspectors.
[
I f-
'.7 During this inspection,.it was found that certsin of your activities appeared to be in noncompliance with AEC requirements and to raise j
questions concerning the safety.of operations. These items and references to the pertinent requirements are listed in the enclosure to this letter.
Pl*ase provide us with.in 20-days,.in writing, with your comments con-bl cercing the. items, any steps that have been or will be taken to correct
.thea, any steps that have been or will.be-taken to prevent. recurrence, and the date.all corrective: actions or preventive measures.were or,will
/(,
i be completed.
,f.t-c6N
>p son ba p
m o
m f,
U s,
(
k m[m m
+
nono,0,,,,,,,,,
CF O
ADOCK 0500 63
/
/
9a/
'_ , i'h, i h*',N ',
ff. 's.h. Z,. N, '.
9, W
, i, '
.*2 L!:'
h*!'~
.w
.j i-i l
Northern States Power Company November 16, 1971 With respect to item B of the enclosure to this letter, we are aware that l
this matter was discussed during your meeting with representatives of the i
O i
Division of Reactor Licensing on November 2, 1971, and that action being taken on your part is referred to in your letter of November 5, 1971, to
[y; i
the Director, Division of Reactor Licensing. To supplement this information 4
which we already have, we request that in your response to this letter
,h you describe the specific actior.d hich you have taken or are taking to gf i
I insure that in the future adeqv. a 'avestigations and evaluations will be conducted prior to restarting thu wactor after an unplanned shutdown.
p.
If you have questions concerning this inspection, we will be glad to p,'
i
$l.-
discuss them with you.
i.-
!..i Sincerely yours, O
/{t fy*
Boyce H. Grier Regional Director i
t.~
Enclosure:
s, '
i; Description of Noncompliance
[j and Safety items i
h
'[,
1 j
0 t
f.
-]
s 1
g'l-f 1
J l
b.
.I I
i j
f i
I
}'
s o..
(-
[,
t.
l
[.
1,
- t. -
v' l
If t-f' L.m
- ,j,).
7,
e.
j 4.-
O i,*
1 l
,[
ENCLOSURE i%
Docket No. 50-263 i.i
- g. :
A.
Certain activities under your license appear to be in noncompliance If
}
with the requirements of License No. DPR-22, as indicated below:
p\\-
I yl.,
Appendix A to Provisional Operating License DPR-22, Section 6.2, pt,.'
Plant Operating Procedure, Paragraph A states in part that, " plant r
operations will be conducted in accordance with written procedures
(,l.'-
I contained in the Operations Manual."
1 j
Contrary to the above, operations were not conducted in accordance k9,l s
E with your written procedures when, in conjunction with recovery from 3
the reactor scram, isolation and emergency core cooling system
[.f initiation which occurred on September 5, 1971, an operator reset t'
the main steam isolation valves, causing them to reopen before an
('l,'
t analysis of system conditions had verified that system isolation
$ '7,! 1 was not required.
B.
Certain activities under your license appear to raise questions E.'
1 concerning the safety of operations as identified below:
[.,i.'
1 i
On September 5,1971, the reactor was restarted following an immediate
{,
investigation of an unplanned reactor shutdown, before a thorough
- k.
(
{
evaluation of all aspects of the occurrence (reactor scram, isolation and emergency core cooling system initiation) had been conducted. The anomalous performance of the main steam isolation valves (MSIV) was 4
not identified until after subsequent review of the occurrence, which 5, i I,
resulted in the reactor being shut down for a further investigation of the unexplained MSIV behavior.
i i
[
t
- i..
V;."
!lst p
4 i
e l
\\..-
9
- l. '
y e
L-I: -
(
t<
l' s sy
-g
.. )[..'#
- .g',.*
e
\\
.:,.s....
a
., ;..) y ;g e g?
'l
.c s.
Y"
'