Management of Commercially Generated Radioactive Waste - U.S. ...

Comment
Number
2-17
Comment
Number
also be evaluated The should therefore be 5 x 10- 7 also be evaluated. The description of severe accidents in Table 6.2.6
f / es pin e it in t
. Table B.2 of PNL-2588 shows a release fraction
of 2 x 10
5 of 00E/ET-0028 indicates a small opening will exist in the cask.
for actinides and other fission products. Note that both of
these release fractions are for accident scenarios that involve creep rupture
Accident n number r 6
6.2.8
8 is
is based
b d o n 2
on number 6.2.7. Number 6.2.8 assumes that
no emergency action is taken to cool the cask involved in the 6.2.7 accident.
This results in 50% of the fuel rods being perforated in number 6.2.8be
in numbe 8 6
instead of only 1% being perforated in number 6.2.7, in addition to 100%
of f the oolantbeing coolant being released in
in both
both accidents,
accidents. Thus, release fractions
of fuel rod cladding. Since in accident number 6.2.8 it is assumed that
50% of the rods fail the release fraction for actinides and other fission
produ oud x -5 if te re t of are sed e
1 x 10 if the results of PNL-2588 are used. Recommend
the basis for the release fractions used in DOE/ET-0028 be reexamined and
e bais for te release fractions used in O 0 be reemed
any discrepancies with the fractions used in the PNL study be resolved.
in number 8 6.2.8 should be 50 times higher than in number 6.2.7.
n nber 2.8
Indeed
hould be 50 te higher than in numr 6.2.7. Indeed. The following discussion shows that the
85
amount of Kr 85 or Kr
released for accident
8 5 , 12, and H the release
fmor
fractions
Kr
given are 50 times higher for ..
8 , the r f s g a 5 t h o
number 6.2.8 than for 6.2.7. However, although mixed fission products and
number 6.2.8, the most severe accidept, has been underestimated. Table
6.2.7 of E/ET-028 indicates that 30% of the Kr 85 actinides are reportedly released in number 6.2.7, only Cs134 and Cs
will exist in fuel rod
137 are
reported as being released reort in n as n number n r r
6.2.8.
a
This can also be seen in Tables
4.1.1-10 and 4.1.1-12 of DOE/ET-0029 which gives the actual number of curiesperforated
released. Note
TOOE/ET-028
that Table 4.1.1-10 gives the curies released for accident
number numhor f 6.2.6, ) 6 Kt a moderate accident a in which only 5% of the cavity coolant is
released and only 0.25% of the fuel rods exhibit cladding.failure. The table
show fission products such as 90 95 inper
Sfisio r such a r
void spaces. Accident number 6.2.8 assumes that 50% of the fuel rods are
perforated so that the release fraction reported in Table 6.2.6 of
so that the ease fracion rpoted in Table cask inv
is 0.15. This table also indicates that the cask inventory
g i Table 3 o e se eteinngt
given in Table 3.3.8 of OE/ET-0028 should be used for determining the
actual number of curies released. Table 3.3.8 indicate 9.5 x I03 curies
in
MTHM. Since Table 6.2.6 indicates that a cask will contain 4 MTHM, c"
9
and Nb 95 and the actinides such as this means a total inventory of 38 x 10 3 curies of Kr 85 Pu
. With a release
239 and Cm being released. Table 4.1.1-12, which lists the radionuclides
released for accident number 6.2.8, the severe accident, does not contain
fraction of 0.15, this results in 5.7 x 103 curies of Kr85 being released.
Table 4.1.1-12 of DOE/ET-0029 shows only 5.3 x 10 curies of Kr5 being
any of the additional fission products or actinides listed for the less
severe accident. Is this simply an oversight or is the contribution to the released.
dose from these nuclides negligible compared to the dose resulting from
the nuclides that are listed?
Paragraph 3: Some discussion should be included describing the composition
of a special train and the advantages and disadvantages resulting from its
A study conducted by Battelle's Pacific Northwest Laboratory, "An Assessment of a special train and the advantages and disadvantages resulting from its
use. Is it a safer mode of transport? Does it have better safeguard
of the Risk of Transporting Spent Nuclear Fuel by Truck," PNL-2588 uses use s t a safer e f trasrt es t ae etter safeuar
release fractions for actinides and fission products other than gases that features?
are significantly higher than those derived from the accidents describedd.25 p.
in E/ET-0028. As previously shown the release fractions for actinides Line 23: Can an aerial radiation survey detect a spent fuel cask that has
and mixed fission products in accident number 6.2.8 should be 50 times higher not been breached and is located inside a building?
than those used in accident number 6.2.7. Table 6.2.6 of DOE/ET-0028 shows
a release fraction of 1 x 10 "8 for actinides and mixed fission products for
accident number 6.2.7. The release fraction for accident number 6.2.8
2-18