ML20028E569
| ML20028E569 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 01/20/1983 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20028E566 | List: |
| References | |
| NUDOCS 8301280020 | |
| Download: ML20028E569 (4) | |
Text
[
g,.f UNITED 5TATES NUCLEAR REGULATORY COMMISSION 3
wasHmoTom, p. c. asses 5
?.
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.8 5 TO FACILITY LICENSE NO. OPR-29 COMMONWEALTH EDISON C0tFANY AND s., 2 IOWA-ILLINOIS GAS AND ELECTRIC COMPANY QUAD CITIES NUCLEAR POWER STATION, UNIT 1 COCKET NO. 50-254
Background
By telephone calls on December 17 and 18,1982, the Commonwealth Edison Company (licensee) informed NRR that the inboard main steam drain isolation valve M0-220-1 for Quad Cities Unit 1 could not pass the leak test required by _
Technical Specifications (TS) 3.7.A.2.a.(2).
All reasonable attempts to re-pair the valve had failed.
The Unit was near the end of a long refueling outye in which extensive high radiation exposure work had been performed, so all available experienced welders were at their exposure limits. Replacement of the valve would require that new welders be procured and qualified. Thus, cutting out the old valve and replacing and testing the new wculd take an estimated five to seven days.
Judging by past experience in similar situations, the time required might be considerably more.
The question then was whether to delay startup to qualify new welders and re-place the valve, or to seek an appropriate basis for relief, fully consistent with radiologically health and safety considerations, that would allow the Unit to operate for a limited time before replacing the valve.
By letter dated December 20, 1982, the licensee requested a change to their Technical Specifications which would allow startup with the inoperable valve.
The details of the original request were clarified by subsequent discussions between the licensee and the NRC Staff.
Evaluation General Design Criterion 55 in Appendix A of 10 CFR 50 requires that all
'l;;.
containment penetrations that are part of the reactor coolant pressure boundary have two containment isolation valves, unless it can be demonstrated that the containment isolation provisions are acceptable on some other defined basis.
l 8301280020 830120 PDR ADOCK 05000254 P
PDR O
2 The attached drawing shrws the two containment isolation valves for the three-inch main steam drain line. These valves are M0-220-1 and M0-220-2 (designated valve numbers 1 and 2). The licensee's basis for plant operation with valve M0-220-1 inoperable is as follows:
1.
The outboard main steam drain isolation valve, M01-220-2, has been demonstrated to have an acceptably small leakage rate. This valve will close upon a Group I isolation if open.
It is normally closed during operation.
2.
Until M0-220-1 valve is restored to operability, valves M0-220-2, 3 and 4 will be verified closed after each valve closure.
3.
Technical Specifications 3.7.D.2 acknowledges that the mit may be safely operated with only one valve in the isolated condition. Valve M01-220-2 will normally be closed during reactor power operation; it needs to be opened only during unit startup to drain the main steam lines or following a Group I isolation to allow movement of the MSIVs.
4.
Downstream of the 1 and 2 valves, the leakage path leads only to the main condenser or to the other main steam lines and the RBEDT. Two other valves, normally closed valves M01-220-3 and M01-220-4, prevent flow through these paths. Any leakage through the 2 and 4 valves to-gether or 2 and 3 valves will be very small.
Following our review of the licensee's proposal, and discussions with the licensee, we have determined that Unit 1 may operate with valve M0-220-1 inoperable, subject to the following new TS requirements:
1.
Valve MO-220-1 will be restored to operability no later than startup after the first Cold Shutdown following a 30-day period after December 21, 1982.
2.
While valve M0-220-1 is inoperable, valves MO-220-2, 3 and 4 will be verified closed after each closure.
3.
During operating Cycle 7, until valve M0-220-1 is restored to operability, valves M0-220-2, 3 and 4 will remain closed, except that when the unit is.
in.the Startup/ Hot Standby Mode, valve M0-220-2, 3 and 4 may be-opened
~
as needed to drain the steam lines, or as needed after a Group 2 isolation to clear the isolation.
P We conclude these measures are adequate for safe plant operation r>nd are f
therefore, acceptable.
4 9
r 3
I Environmental Consideration We have determined that the amendment does rot authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant envirorsnental impact. Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the stand environmental impact and, pursuant to 10 CFR 551.5(d)(4) point of
, that an environmental impact statement, or negative declaration and environ-mental impact appraistl need not be prepared in connection with the issuance of this amendment.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated, does not create the possibility of an accident of a type different from any evaluated previously, and does not involve a significant reduction in a margin of safety, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Consnission's regulations and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Dated:
Jar.uary 20, 1903 Principal Contributor: Roby Bevan and Doug Pickett
~/,.
t
~
[k.;;.,.a:'
.v.w ;ys%4V.,:. * %
L,
.ex. - gwwwg.
m x 7:,,...c'...s
, ?. a. -
- .m%:et V;w.% oc%
- fu 441
-, L. -
..'-.*Q*s,; Q:
e.
. ;~; *:.'a-;?i s.g3.g ' '
w.;g, y s.
- <:7.:*-
4
.4.'a~* gf; ue n.-
.: e
{
- A 1:. a--
.g ;.,.4.y.
Jpp,,
.n,
, - lt e
s S. / *W'h * :~ f= '*
- j.**
. ' 'h..'.
(
2 J
a pen.
,,;a,'; y,,.
Q
' ~~";"::v4'4;$
4 Q4,0ll9)>
3
..? :. ' '.,i. :)
.OC f.
g
- i Ykk?N.'.j',l'%(;.e,w m p
.4 u
-A T'$Y'",
- )
(
- e.,
%,s**1
-_7,,,,,e N g
- ; c. :.
lh;*.jf ",'~-
~
. p v.
- W: :p ?:Qiejsff 45
_w.
x
,sengg h
,- 1*:Q'.: of i.1..
y
- -;4U4
'Y bukff-
,\\
s-
- y<~
~
...s.
T
~~',.
l
,, e;..
3 e
I L
h-I
[
t W
/.C g.,.
b%
' T.
~;^}
O f.-
LS~ ~~2 n,'=.
'f ? '
- s..
3 4,
.a O
d
.c
~
f
{lN La
- 4. :. c -
.y
.i
/
' ~ -
=;;,+.
_-.a-
,'y, l
' r";
t r
7 ei d
i-.
j i
xa
./
I
~h
. ns -
e
.3 N, a _-
1
/
4