Description and History: 1§26-1972
RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
Location
14 Apr 48
30 Apr 48
Enjebi (Janet)
Aomon (Sally)
37 KT
49 KT
Zebra
14 May 48
Tower 200°
Tower 200°
Dog
Easy
7 Ap 51
20 Apr 51
Tower 300°
lower 300°
Runit (Yvonne)
Enjebi (Janet)
Class.
47 KT
Item
24 May 51
Tower 200°
Enjebi (Janet)
Class.
Ivy
Mike
31 Oct 51
Sur face
Airdrop
1500°
2000’ North of
Runit (Yvonne)
600 KT
Castle
Nectar
13 May 54
Barge
Mike Crater
1.69 MT
Sandstone
Greenhouse
Event Name
Date (GCT)
X-ray
Yoke
George
King
Lacrosse
Redwing
Yuma
15 Nov 52
4 May 56
27 May 56
Tower 200’
Sur face
13.7 KT
Class.
Class.
Class.
Tower 300’
Eleleron (Ruby)
Class.
Tower 200'
Apache
Huron
8 Jul
21 Jul
Cactus
Butternut
Koa
Wahoo
5
11
12
16
Holly
Yellowwood
20 May 58
26 May 58
May
May
Jun
Jun
58
58
58
58
Wainut
Linden
Elder
Oak
Sequoia
Dogwood
Scaevola
14 Jun
18 Jun
27 Jun
28 Jun
1Jul
5 Jul
14 Jul
58
58
58
58
58
58
58
Barge
Barge
Barge
Underwater
150°
Barge
Barge
Barge
Barge
Barge
Barge
Barge
Olive
Pine
Quince
Fig
22
26
6
18
58
68
58
5B
Barge
Barge
Surface
Surface
Magnolia
Tobacco
Rose
Umbrella
Pisonia
26
30
2
8
May
May
May
May
17 Jul
Jul
Jul
Aug
Aug
56
56
56
58
58
58
58
58
darge
Barge
Runit (Yvonne)
Lujor (Peart)
Mike Crater
Mike Crater
Class.
IBKT
Low Yield
1.37 MT
Class.
Barge
Barge
Laqoon
Lagoon
Class.
Class.
Lagoon
Lagoon
Lagoon
Lagoon
Class.
Class.
Class.
Class.
Lagoon
Lagoon
Lagoon
Reef
Lagoon
Lagoon
Lagoon
Class.
Class.
Class,
B.OMT
Class.
Class.
Class.
Lagoon
Lagoon
Runit (Yvonne}
Runit (Yvonne)
Class.
Class.
Class.
Class,
Lagoon
The principal radioisotopes that made up the residual radioactivity on
Class.
Class.
Runit {Yvonne}
Lagoon
Lidifbut (Gene)
Ocean
Barge
Conditions that were not readily visible included contaminated soil on
manyislands of the atoll and contaminated sediments on the bottom of the
lagoon. The lagoon also contained many miles of cable that had been laid
between islands for instrumentation, communication, and the activation
of the nuclear devices.
Class.
Sur face
Barge
Surface
Underwater
500°
h. Tons of concrete and metal debris remained.
40 KT
Boken (Irene)
Runit (Yvonne)
Aomon (Satly}
Runit (Yvonne)
21 Jun 56
2 Jul
Runit {Yvonne}
10.4 MT
Surface
Tower 200'
Tower 30U’
Airdrop
Inca
Mohawk
56
56
56
56
Elugelab (Flora)
blasts as well as by efforts to restore the area for continued use.
. Coconut palms and other vegetation were destroyed in many areas.
. The construction of causeways, landfills, and the excavation of
borrow areas in the course of test preparation had modifiedthe atoll
topography.
Large structures and bunkers for test measurement or observation
remained after testing was completed.
£. Semipermanent buildings were left standing, especially on the islands
of the southeast.
Class.
Class.
Tower 300’
Jun
Jun
Jun
Jun
Eleleron (Ruby)
. Surface profiles in the vicinity of ground zeroes were changed by
18 KT
Agmon (Sally)
30 May 56
6
11
13
16
Runit (Yvonne)
Tower 200°
Erie
Seminole
Black foot
Kickapoo
Osage
Hardtack |
8 May 51
Tower 200’
had been, and on Boken (Figures 1-55, 1-56 and 1-57).
Yield
of Burst
Operation
57
b. Large craters were formed on the reefs on the north end of Runit, to
the Northeast of Bokinwotme (Edna) where Elugelab and Lidilbut
Class.
OO
Enewetak Atoll following the test period were:
a. Cobalt-60, an emitter of gammarays and beta particles, with a half-
—
Type and
Height
aa
56
Notes: Dates are determined from the Greenwich Civil Time (GCT} of the detonation.
lests are given as kilotons (KT), megatons (MT), or as “Classified” {Class.)
Height or depth of burst are fromother sources.
FIGURE 1-54. NUCLEAR EVENTS AT ENEWETAK ATOLL.
FIGURE 1-55. CRATERS ON RUNIT.