III.
MAJOR FIELD INVESTIGATIONS-1965
Preface
An extended cross country field trip was undertaken
during August and September of 1965.
The purpose of this
trip was to carry out a number of interrelated studies of
environmental radioactivity at a wide variety of geographical
locations and with several different types of equipment.
In
addition, the trip offered an opportunity for a number of
groups engaged in the study of environmental radiation problems
to discuss their methods, problems, and future plans as well
as to intercompare equipment responses at the same locations.
During much of this trip we were accompanied by a team from
the New York University (NYU) Cosmic Ray Laboratory.
Several
other research groups joined us for particular segments of
the trip.
The major experiments completed by us were a resurvey
of a number of our 1962 and 1963 field sites to compare
present natural and fallout gamma dose rates with our previous
Measurements; a determination of cosmic ray ionization as a
function of altitude using data obtained at land sites at
altitudes up to 12,000 feet and over large lakes at altitudes
up to 10,000 feet;
a study of NaI(Tl) detector response to
cosmic rays as a function of altitude; a series of simultaneous
measurements with the NYU team over several lakes; field
spectrometric estimates of 137cs soil. activity at or near a
number of U. S. Department of Agriculture - HASL Worldwide
90sr soil sampling Sites for comparison with radiochemically
determined 13’cs concentrations; an intercalibration with
teams from the Lawrence Radiation Laboratory (LRL), Rice
University, and NYU over two solid rock outcrops of widely
differing y-ray activity; simultaneous measurements with the
NYU team at several land sites to estimate B-ray activity;
measurements at sites having very low gamma and cosmic ray
activity such as deep mines or serpentine outcrops;
gamma dose rate measurements
with birth defect data,
in western Nebraska
and
for correlatio
in New Mexico near Alamagordo,
intercomparison with an aerial radiation survey and in
Dallas, Texas,
experiment.
for
for comparison with a continuous monitoring