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HEADQUARTERS

TASK

GROUP

7.1

JOINT TASK FORCE SEVEN

Los

ALAMOS
J

ScIENTIFIC

Division,

P.O.Box

Alamos.

Los

410448

LABORATORY

1668

New Mexico

29 July 1954

Gordon M. Dunning

Biophysics Branch
Division of Biology and Medicine
U. S. Atomic mergy Commission

washington 25,

,

_. _US DOE ARCHIVES
326US ATOMIC EXERGY

RG

COXLESION
DIVISIG if OF BiCLOGY
& MEDICINE
Collection

D. C.

,
3366

Box
.

Dear Gordon:

PoldcrM@4S 3-8 Mamtinoe + FarcoytT

Thank you for your complimentary letUen.The msintenence of records at JY
an operation leaves much to be desired and it entails the lergest work
load of the unit. We have been studying methcds to improve present
dosinetry practices and hope that by experience we can improve and simplify
the system presently used at the Nevada and Pacific Preving Grounds,
Two conspicuous deficiencies were noted during the operetion:
a. Ina widely dispersed operation, cortrol rust be exerted through
the use of self-reading pocket dosineters -- but these dosimeters should

reflect film badge dusage, should be operstive in areas of high moisture

and under ruused usage, and should be easily; ~ainteined and reraired. At
Castle we were hindered by creap and unreliable pocket dosimeters as well
as hign loss rates,
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b. igh cortarination conditions, dispersal c
ies aboard
avtered Sete ss ane ue processing @
asd recording o
ses under
ve exposures
00 Slow for adequate curtrel o
there” is “lack: of a coordirated, plenned prograx
iclociczily ccntaninated area, Armuber of exposures Lstweer 4 and
rigems were the result of late film recordings "catching up" with a
& continued to work in a ccntaninated area without respite.
it viet 42 linat of 3.0 roentgens would rave previded 6 buifer that
teriallvy reduced the murver cl overexrcsures,
nanelysis cf exposures reveals 23 exposures in encess of ler
he 3 exposures cf Task Group 7.1 were military jerscennel of a

wio were assessed readings on the basis of cne film badge left i
or norgerik Atoll curing 2 period oF radioactive
set
is believed tc be 40 - 45 roentzsens.

Three TG 7.2 boat operators returied film beczes reading $5, 95 and 9
roentsens. Cur investigation indicated their activities dic net substantiate
these hich exposures and left their ectuel exnosure subject to question.
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