vy

pai

A. C. Graves

-b-

June 28, 1951

Table III

sstimated total cose in roentgens from JANGLE shots.

(Miles)

5

10

4

920

Distance (Milvs)

20

35

50

100

100

9

1.3

0.

0.03

h.6

Leh

Oo

5.2

0.6

1

!

1200

240

20

3

|

15

160

63

15

* = Lose beyond 0 miles will increase with wind velocity for all
three cloud heights.

ee

Cloua Height .

ee

Wind velocity = 10 mph*, mean particle size = 75 microns (Trinity)

Table IV

Estimated total dose in roentgens for JANGLE,
Wind velocity = 10 Nph", mem particle size = 20 microns.

:

,t
|

!
|

Cloud Height

(Miles)

3

:
9

|
,

1
3

|

5

10

1h

18

istance (Miles)

20

35

50

100

160

62

15

5.2

0.6

60

18

18

7

0.9

2

8

10

7

1.7),

0.5

.

* — 4¢ 50 miles, level decreases for increasing wind velocities if
cloud height is 3 miles.

The estimated doses in Tables IIT and IV will bear further comment.
Sh
re
tet
”
.

Our interests from the safety viewpoint center on the region from

35 to 100 miles.

|

Tables TII shows a marked increase of dose with

cloud height and is apparently in contradiction with the s tatement
that the surface burst is the best.
It is felt, nevertheless, that
the deposition from a low cloud maywell be higher than indicated
because of the confinement of the cloud to the valleys, It is
mainly our uncertainties about the path of a low cloud, the extent
of neutron activation, and the true varticle size distribution which
leads to the conclusion that the surface shot is the best one to
start with,

i
i

Select target paragraph3