ML20215J247
| ML20215J247 | |
| Person / Time | |
|---|---|
| Site: | 07003000 |
| Issue date: | 10/03/1986 |
| From: | Johnson I COMMONWEALTH EDISON CO. |
| To: | Jennifer Davis NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| 2210K, 27480, NUDOCS 8610240363 | |
| Download: ML20215J247 (7) | |
Text
'
70- 3xo
\\ Commonwealth Edison i } 72 West Adams Street, Chicago Illinois 7 Aearess sepiy to: east office Box 7e7 v
Chr.ago, liliros 60690 - 0767 RETURN TO 396-SS
,/
e e,
Mr. John G. Davis 8
VgN Director of Nuclear Material Safety
- RECEIVED and Safeguards g
g l
U.S. Nuclear Regulatory Commission OCT 61986 hI-Washington, D.C.
20555 l
9-U.LhucuAR RU;uarou :
t
\\
COMMin:cn 1
Subject:
Braidwood Station \\ nits 1 and 2 nun U
s M838S"*h Special Nuclear Materials License 4
+'TrMp Number SNM-1938 i.
NRC DockeWNof.' ISO 945iMasd 50-457
Dear Mr. Davis:
n.
t Ll:1 !'
This is to request amendment of the Braidwood fuel storage license, SNM-1938. Revision of certain existing license conditions is necessary to permit placement of the startup sources in fuel assemblies prior to the l
commencement of core loading. These revisions are necessary to minimize the j
number of times that each new fuel assembly must be handled on the core load critical path and will diminish the possibility of accidental damage to the l
fuel.
I Attachment A to this letter contains the proposed changes to I
SNM-1938 and the basis for each change. Expedited consideration of this amendment is requested. We anticipate receiving a fuel loading license for Braidwood 1 on October 15, 1986. The revision to license SNM-1938 is needed 4
prior to the issuance of the Part 50 license to permit transfer of the californium neutron sources in advance of the commencement of core loading l
and finalization of the core loading procedures. It appears that issuance of the amendment by October 15, will provide adequate lead time.
According to 10 CFR 170.11, no fee is required for this license amendment.
i Please address any questions you may have regarding this matter to this office.
Very truly yours, i
- x h
(
.'((
Sn NO I. M. Johns j
p T 3 l! Nuclear Licensing Administrator l
M NE Q
O twAc"y fQY)
,0 m yss Attachsen Il
- R:?.,
y 8610240363 861003 l
2210K PDR ADOCK 07003000 C
pop g
l
.-c---
DOCKET N0.
28'SDO C0!! TROL NO.
7MO DATE OF DCC. ___(# 83 2 --
0.1.TE RC'/D.
/d #4 26 FCUF FDR -
1_ /
TCAF IPOR I&EREF,__
MILT:ZDS M FCTC DiitR DATE 8
/d it.!IIAL _
- O s ATTACHMNT A PROPOSED CHANGED TO SNM-1938 Present Wording:
19 Puel assemblies shall be stored in such a manner that water would drain freely from the assemblies in the evet of flooding and subsequent draining of the fuel storage area.
20.b The fuel assemblies shall be stored in a checkerboard pattern.
I J
l proposed Wording:
19 Puel assemblies shall be stored in such a manner that water would drain freely from the assemblies in the event of flooding and subsequent draining of the fuel storage area. However, two fuel assemblies may be placed in two water filled damaged fuel storage containers for Primary Neutron Source installation and shielded storage provided that the water used is at greater than 2000 ppm boron concentration.
20.b The fuel assemblies shall be stored in a checkerboard pattern in the spent Puel Racks. Two fuel assemblies may be placed in two damaged fuel storage containers for Primary Neutron Source installation and shielded storage provided the center-to-center spacing of these assemblies and all other adjacent fuel assemblies exceeds 20 inches.
Reason for Changes:
Due to ALARA considerations it is desirable to install the two californium primary neutron sources into two new fuel assemblies in the j
spent fuel pit.
Two damaged fuel storage containers filled with borated water will be used for radiation shielding. The containers will be located in the failed fuel container rack shown in PSAR figures 9.1-2 and 9.1-4 (enclosed). This rack is designed to maintain the center-to-center spacing at greater than 20 inches. The-installation operation will be performed shortly before the start of core loading and the two new fuel assemblies with installed neutron sources will be temporarily stored in these containers until transferred to the reactor.
l l
c-. - -
a n.
.,.-,.,_,-_,.n,_
r
- s.
. '. Basis for ch'anges:
The two fuel assemblies to receive primary sources will be installed in failed fuel containers located in two nonadjacent failed fuel container rack locations 44 inches apart (nominal). The failed fuel container has the cylindrical dimension of a 14 inch schedule 10 pipe and contains a stainless steel angle framework centered in the container to support the fuel assembly. This framework is nominally 9 inches square. Between the two loaded failed fuel containers will be a third, borated water filled failed fuel container to be used as a shielded temporary storage location for the primary source rod. When we unload the new fuel vault into the spent fuel pit, the closest a new fuel assembly would be stored with respect to a source bearing assembly would be 20 3/8" inches.
22"
- '=
22'
=.
./y x
', + ' />c
,x.. ~
Y n'
y.
X ,
X-y X X M(A E k X lK
' W AN x >< hed X N
,x g
y x..
41144 x
,c g
X,.
~ '.
K 4x s
- ~
>(
X 20 %,,
t W
cen4er +o cenler Twenty inches is greater than the minimum checkerboard center-to-center spacing. This arrangement has been analyzed by NUS Corporation the original rack criticality analyst, and found to have no adverse affect on the original results.
The total amount of water used will not exceed 250 gallons. Even if this borated water were to completely leak into the surrounding Spent Fuel Pit, it would be less than 1/4 inch in depth, still more than 16 inches below the active fuel in storage.
Normal station radiation procedures will be used to support the movement of primary neutron sources. Health Physics personnel will monitor personnel area dose rates, conduct area surveys and contamination swipe surveys, and appropriately post any radiation areas. personnel dosimetry will include badges specifically designed for neutron extmsure.
Expected dose rates for source loading both with and without borated water shielding are as follows for selected areas:
,e.
. Area Without Water With Water Welding Work Area 158 mrem /hr 0.00326 mrem /hr (9 ft. above source) 426' elevation at South 4.16 mrem /hr 0.079 mrem /hr end of pit North SFP wall at 688 mrem /hr 50.8 mrem /hr source level 426' elevation at North 9.51 mrem /hr 5.9 E-6 mrem /hr end of pit l
l 2210K l
i g*
5 VOw we e
j J
.t g
o O. g i
r.w O
MQ L
3 l':l y
3:
~.'l s l
,1 r.;
/
e e
e e
2
- f
$8 e
e e
e G
z a
o au-:
W t
s L
st.
v
-.l.
.s 4 q g K>
L b
g-Q-i e
e e
e 5
A uo
.c E1 t
.i)
MC e
e e-e
- s...
,o a.
.-~
.a e
e e
e e
o k
Pr, r.-
4 e,1 s
.,a w
Qd e
e e
e io
?
k res
~
.~
~
es' 3
O O
O py f.'
s 3Jt e.W.
s.Q,
.z.
m n
n 01 O
(TV e
e G
y*'*w-p0 j
j u 4,,
., -s.
.i.
y at 4
e OU G
G l
I 8
l e
e
's 0
~
1 (e
i tL e
,l
~
-t' O1
- a o
r oV 8
~
zz a
~
0 0
W e
O w5 g
a 7
be e s p-r:-
}
8 z
~
O
- g n
Zb z ZF b li o
4 O
o
]
r m
an BYRON /BR AIDWOOD STATIONS FIN AL S AFETY AN ALYSIS REPORT FIGURE 9.1-2 SPEtiT FUEL STORAGE RACK ARRAt4GEMEf1T.
I
- 6.
W/
DY]%W) 1 l
suPacRr PLATE
'8450 M.M NOM.
i C
O Q
s b
V f
v v
i O
LEVELING LEO g
& 40 CCWN BCLI RACK SASE uD BYRON /BR AIDWOOD STATIONS FIN AL S AFETY AN ALYSIS REPORT FIGURE 9.1-4 l
i FAILED FUEL CONTAINER RACK i
,_.