Total Cost ($/gal) 
thicknesses. Based on 400-day irradia- 
tion to 10,000 Mwd/ton 
ulation a typical reactor specific power 
of’ 1,000 Mw/40 ton = 25 Mw/ton is 
assumed. On this basis, the reactor 
operating time would be 80, 160, 320, 
and 400 days for 2,000, 4,000, 8,000, 
and 10,000 Mwd/ton, respectively. 
Fission products to be considered for 
the shielding calculations are Ba!*° 
(La), Zr, Nb?s, Ce!44 (Pri44), C137 
—-— $0.30/goal/yr 
$ 0.041/gal/yr 
$ 0.013 /gal/yr 
Oo - 4 6 8 10 12 14 16 18 20 22 24 26 
Cooling Time (years) 
nominal capacity) as function of shield 
thickness 
and Ru! (Rh!), Table 2 gives the 
number of curies of each of these fission 
products present at time of discharge 
from the reactor for various reactor 
operating times. 
Since 800 gal of high-activity waste 
per metric ton and a specific power of 
25 X 10° watts have been assumed, 
curies/gal = A(curies/watt) * 2.5 X 
107/800 = 3.1 X 104A. The specific 
activities are listed in Table 3 for 400- 
day irradiation at 25 Mw/ton. 
Shielding calculations were made for 
a 4-ft id. carrier holding 250 gal of 
waste from fuel irradiated 400 days 
(10,000 Mwd/ton). A maximum per- 
missible dose rate of 10 mr/hr at the 
wall of a 9-ft-wide railroad car was 
the basis for determining the shield 
thickness. 
Figure 12 shows the total dose rate 
at the car wall as a function of the oool- 
ing time. 
Combined cooling and shipping 
costs. For a fixed irradiation, the 
combined cost of storage and shipping 
FIG. 15. Combined shipping and stor- 
age costs for storage costs of $0.013, 
$0.041, and $0.30/gal/yr. Based on 
250 gal shipped in 4-ft-i.d. sphere, 800 
gal waste per ton spent fuel, 400-day 
irradiation to 10,000 Mwd/ton 
100 36 = 
1,000-day _ . 100-day 
30 
10 
~ 26 
2 5,000-day 2 
= cooling time 3 
fe rf c 
E y 2 BE 34 
1 o° 
3° 500-day \|. & * 303 
« = 2 
3 = 16 2 26 
é E : 
= 2 22 
= 
0.10 10 = 18 
8 S 
_ -10,000- day é g 14 
I 
-30,000- day 4 2 : 
0.01 2 : : (SS 
° Og 2 4 6 8 02 3 4 ee) Tt. 38 85 10,000 20000 30,000 
Shield Thickness (inches of lead) Shielding Thickness (inches of lead) Cooling Time (days) 
FIG. 12. Dose rate at car wall for FIG. 13. Weight of spherical lead FIG. 14. Shield weight to give 10-mr/ 
various cooling periods and_ shield shipping carrier (4-ft'id. and 250-gal hr surface dose (250 gal in 4-ft-i.d. 
sphere; 800 gal waste per ton, 400-day 
irradiation to 10,000 Mwd/ton) 
will be a function of cooling time and 
shipping distance. 
Carrier weights are plotted as a func- 
tion of shield thickness in Fig. 13 for a 
250-gal waste capacity. Using the 
shield thicknesses from Fig. 12 that 
give a 10-mr/hr tolerance dose (for 
400-day, 10,000-Mwd/ton irradiation), 
carrier weights are plotted as a function 
of cooling time in Fig. 14. It is as- 
sumed that the empty carrier must be 
returned to its point of origin and that 
carrier cost and handling charges would 
not be significantly influenced by cool- 
ing time compared to freight charges. 
The freight charges per ton of carrier 
(round trip) are based on the following 
rates: $1.40, $2.60, and $4.50 for one- 
way distances of 200, 500, and 1,000 
miles. The optimization is carried out 
for these three distances and for unit 
storage costs of -$0.013, $0.041, and 
$0.30/gal/yr from Table 1. The basic 
costs appear in Table 4 and the com- 
bined results in Figs. 15-17. 
BIBLIOGRAPHY 
1. J. A. Lane, Nucuteonics 12, No. 10, 65 (1954) 
2, Palmer C. Putnam, ‘‘Energy in the Future’’ 
(D. Van Nostrand Co., New York, 1953) 
8. A. B. Joseph. Thestatus of land disposal of 
atomic reactor waste, presented at the Nuclear 
Engineering and Science Congress, Cleveland, 
Dec. 12-16, 1955 
4. ‘Project Separation.’ Processing of Spent 
Fuels. AEC survey at MIT (1954) 
133 
